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Sample records for haemophilus somnus exposure

  1. Aerosol challenge of calves with Haemophilus somnus and Mycoplasma dispar

    DEFF Research Database (Denmark)

    Tegtmeier, C.; Angen, Øystein; Grell, S.N.

    2000-01-01

    The aim of the study was to examine the ability of Haemophilus somnus and Mycoplasma dispar to induce pneumonia in healthy calves under conditions closely resembling the supposed natural way of infection, viz, by inhalation of aerosol droplets containing the microorganisms. The infections were....... Also, one calf was exposed to M. dispar followed by exposure to a sterile saline solution 11 days later, and one calf was only exposed to a sterile saline solution. Just one animal, only challenged with H. somnus, developed a focal necrotizing pneumonia, from which H. somnus was isolated. Thus...

  2. Haemophilus somnus (Histophilus somni) in bighorn sheep

    Science.gov (United States)

    2006-01-01

    Abstract Respiratory disease and poor lamb recruitment have been identified as limiting factors for bighorn-sheep populations. Haemophilus somnus (recently reclassified as Histophilus somni) is associated with respiratory disease in American bison, domestic sheep, and cattle. It is also harbored in their reproductive tracts and has been associated with reproductive failure in domestic sheep and cattle. Therefore, reproductive tract and lung samples from bighorn sheep were evaluated for the presence of this organism. Organisms identified as H. somnus were isolated from 6 of 62 vaginal but none of 12 preputial swab samples. Antigen specific to H. somnus was detected by immunohistochemical study in 4 of 12 formalin-fixed lung tissue samples of bighorn sheep that died with evidence of pneumonia. Notably, H. somnus was found in alveolar debris in areas of inflammation. The 6 vaginal isolates and 2 H. somnus isolates previously cultured from pneumonic lungs of bighorn sheep were compared with 3 representative isolates from domestic sheep and 2 from cattle. The profiles of major outer membrane proteins and antigens for all of the isolates were predominantly similar, although differences that may be associated with the host–parasite relationship and virulence were detected. The DNA restriction fragment length profiles of the bighorn-sheep isolates had similarities not shared with the other isolates, suggesting distinct phylogenetic lines. All of the isolates had similar antimicrobial profiles, but the isolates from the bighorn sheep produced less pigment than those from the domestic livestock, and growth of the former was not enhanced by CO2. Wildlife biologists and diagnosticians should be aware of the potential of these organisms to cause disease in bighorn sheep and of growth characteristics that may hinder laboratory detection. PMID:16548330

  3. Preimplantation bovine embryos: Pathobiology of Haemophilus somnus exposure and resistance mechanisms to vesicular stomatitis virus

    Energy Technology Data Exchange (ETDEWEB)

    Thomson, M.S.

    1988-01-01

    Preimplantation bovine embryos were exposed in vitro to H. somnus to determine if the bacteria would adhere to zona pellucida-intact (ZP-I) embryos or adhere to or infect ZP-free embryos. The effect of H. somnus on embryonic development in vitro was also investigated. Electrophoretic comparisons of outer membrane proteins of H. somnus revealed 2 major protein bands common to 10 H. somnus isolates. A monoclonal antibody produced against the outer membrane proteins reacted to one of the major protein bands. The sensitivity of a nucleic acid probe for detection of vesicular stomatitis virus (VSV) was validated in cells in culture and used to determine if the synthetic double-stranded complex of polyriboinosinic and polyribocytidylic acids (poly I:C) would induce viral resistance in cultured bovine embryos. Two {sup 32}P-nick translated probes of high specific activity prepared from plasmids containing nucleic acid sequences of VSV virus were employed for viral mRNA detection in the tissue culture cells using a DNA-hybridization dot-blot technique. Using one of the probes, the technique was applied to detect differences in viral replication between four groups of bovine embryos (nonexposed, exposed to VSV virus, poly I:C-treated, and poly I:C-treated and exposed to VSV). The nucleic acid probe was sufficiently sensitive to detect differences in quantities of VSV mRNA among embryo treatment groups, resulting in the demonstration that resistance to viral infection was induced in day 9 bovine embryos.

  4. Development of a PCR test for identification of Haemophilus somnus in pure and mixed cultures

    DEFF Research Database (Denmark)

    Angen, Øystein; Ahrens, Peter; Tegtmeier, Conny

    1998-01-01

    . somnus by DNA-DNA hybridization as well as representatives of the 16 ribotypes previously described within this species. The specificity of the test was evaluated on a broad collection of strains within the family Pasteurellaceae and on other Gram positive and negative species. None of these strains gave......Based on the 16S rRNA sequences of a collection of well-characterized strains of Haemophilus somnus a set of primers was selected as candidates for a species-specific PCR test. All investigated H. somnus strains were found positive in the test, including 12 strains earlier found to represent H...... for identification of bacteria belonging to this phenotypically heterogeneous and often slow growing species....

  5. Complexities of the pathogenesis of Mannheimia haemolytica and Haemophilus somnus infections: challenges and potential opportunities for prevention?

    Science.gov (United States)

    Czuprynski, Charles J; Leite, Fabio; Sylte, Matt; Kuckleburg, C; Schultz, Ron; Inzana, Tom; Behling-Kelly, Erica; Corbeil, Lynette

    2004-12-01

    Progress in producing improved vaccines against bacterial diseases of cattle is limited by an incomplete understanding of the pathogenesis of these agents. Our group has been involved in investigations of two members of the family Pasteurellaceae, Mannheimia haemolytica and Haemophilus somnus, which illustrate some of the complexities that must be confronted. Susceptibility to M. haemolytica is greatly increased during active viral respiratory infection, resulting in rapid onset of a severe and even lethal pleuropneumonia. Despite years of investigation, understanding of the mechanisms underlying this viral-bacterial synergism is incomplete. We have investigated the hypothesis that active viral infection increases the susceptibility of bovine leukocytes to the M. haemolytica leukotoxin by increasing the expression of or activating the beta2 integrin CD11a/CD18 (LFA-1) on the leukocyte surface. In vitro exposure to proinflammatory cytokines (i.e. interleukin-1beta, tumor necrosis factor-alpha and interferon-gamma) increases LFA-1 expression on bovine leukocytes, which in turn correlates with increased binding and responsiveness to the leukotoxin. Alveolar macrophages and peripheral blood leukocytes from cattle with active bovine herpesvirus-1 (BVH-1) infection are more susceptible to the lethal effects of the leukotoxin ex vivo than leukocytes from uninfected cattle. Likewise, in vitro incubation of bovine leukocytes with bovine herpesvirus 1 (BHV-1) potentiates LFA-1 expression and makes the cells more responsive to leukotoxin. A striking characteristic of H. somnus infection is its propensity to cause vasculitis. We have shown that H. somnus and its lipo-oligosaccharide (LOS) trigger caspase activation and apoptosis in bovine endothelial cells in vitro. This effect is associated with the production of reactive oxygen and nitrogen intermediates, and is amplified in the presence of platelets. The adverse effects of H. somnus LOS are mediated in part by activation of

  6. Initial lung lesions in two calves experimentally infected with Haemophilus somnus

    DEFF Research Database (Denmark)

    Tegtmeier, Conny; Bloch, B.; Jensen, N.E.

    1999-01-01

    electron microscopy (TEM). Inoculation with H. somnus resulted in the development of acute pulmonary lesions within 3.5 h. H. somnus antigen was demonstrated only within the luminal spaces of the airways and in one area of bronchio-associated lymphoid tissue (BALT). As observed by TEM, the bacteria were...

  7. Isolation of Haemophilus somnus from dairy cattle in KwaZulu-Natal : an emerging cause of 'dirty cow syndrome' and infertility? : short communication

    Directory of Open Access Journals (Sweden)

    R.D. Last

    2001-07-01

    Full Text Available Haemophilus somnus was consistently isolated from vaginal discharges of dairy cows submitted from field cases of vaginitis, cervicitis and/or metritis in the KwaZulu-Natal Midlands during the period July 1995 - December 2000 and from the East Griqualand area in November/December 2000. The purulent vaginal discharges, red granular vaginitis and cervicitis, and pain on palpation described in these cases was very similar to that reported in outbreaks of H.somnus endometritis syndrome in Australia, Europe and North America. In all the herds involved in these outbreaks, natural breeding with bulls was employed. Although there was a good cure rate in clinically-affected animals treated with tetracyclines, culling rates for chronic infertility were unacceptably high. Employment of artificial insemination in these herds improved pregnancy rates in cows that had calved previously, but many cows that had formerly been infected failed to conceive.

  8. Characterization of bovine Haemophilus somnus by biotyping, plasmid profiling, REA-patterns and ribotyping

    DEFF Research Database (Denmark)

    Fussing, V.; Wegener, Henrik Caspar

    1993-01-01

    A total of 105 strains of H. somnus isolated from cattle in Denmark and other countries during 1982-1951 were compared with regard to biotypes (fermentation of 8 different sugars), plasmid profiles, Taq1 restriction endonuclease analysis of chromosomal DNA (REA-typing) and EcoRI-generated DNA...... restriction fragment length polymorphisms of rRNA genes (ribotyping). Eighty-four strains originating from cases of pneumonia, and 21 originating from the genitals of bulls were included in this study. Biotyping yielded 21 different types. Twenty-two of the isolates contained plasmids, and these were divided...... into 12 distinct plasmid profiles. Analysis of chromosomal DNA restriction patterns, resulted in 33 different REA patterns and 16 different ribopatterns in the investigated strains. Biotypes, REA-types, and ribotypes generally showed good correlation, whereas plasmid profiles did not correlate with any...

  9. Comparison of bacterial cultivation, PCR, in situ hybridization and immunohistochemistry as tools for diagnosis of Haemophilus somnus pneumonia in cattle

    DEFF Research Database (Denmark)

    Tegtmeier, Conny; Angen, Øystein; Ahrens, Peter

    2000-01-01

    examination were included in the study. The PCR-detection was performed on three different samples: plate-PCR (detection on plate washes after incubation of lung tissue on agar plates); swab-PCR (direct detection on a swab from the cut surface); and, whenever possible, a bronchus-PCR (direct detection...... be considered as a supplementary tool in the diagnosis of H. somnus induced calf pneumonia....

  10. Haemophilus parasuis infection in swine.

    Science.gov (United States)

    Riley, M G; Russell, E G; Callinan, R B

    1977-10-01

    Septicemic disease occurred in 49 of 126 pigs several days after being transported 80 km. All affected pigs died. The main changes in acutely affected pigs were skin discoloration, pulmonary edema, arthritis, meningitis, and renal glomerular thrombosis. In peracute cases, gross findings were minimal. Haemophilus parasuis was isolated from multiple organ sites in most affected pigs. Haemophilus parasuis was isolated from nasal swab specimens from 17 of 20 clinically normal pigs on the farm of origin. Fatal acute septicemia was reproduced in 2 pigs by intravenous or intratracheal exposure to an isolant of H parasuis obtained from 1 of of the 49 fatally affected pigs. Aerosol exposure of 5 pigs resulted in mild pneumonia in 4 pigs and severe pneumonia, pleurisy, pericarditis, and terminal septicemia in 1 pig.

  11. Haemophilus Infections - Multiple Languages

    Science.gov (United States)

    ... Know - Af-Soomaali (Somali) PDF Centers for Disease Control and Prevention Spanish (español) Expand Section Haemophilus Infections: MedlinePlus Health Topic - English Infecciones por Haemophilus: Tema de salud de MedlinePlus - español ( ...

  12. The SomnuSeal Oral Mask Is Reasonably Tolerated by Otherwise CPAP Noncompliant Patients with OSA

    Directory of Open Access Journals (Sweden)

    N. Katz

    2013-01-01

    Full Text Available Compliance with CPAP is the major limiting factor in treating patients with OSA. The novel SomnuSeal mask is an oral self-adaptable mask located between the teeth and the lips ensuring that there are no air leaks or skin abrasions. Fifty patients with AHI>20, who failed previous CPAP trials, were asked to sleep with the mask for one month. In all patients, the mask was connected to an AutoPAP machine with a heated humidifier. Efficacy, convenience, and compliance (average usage for 4 or more hours per night were monitored. Fifty patients (41 m and 9 f, mean age 57±12 years, BMI 33.6±4.9 kg/m2, and AHI 47±23/h participated. Eleven were classified as compliant (average mask usage of 26 nights, 4.7 hours per night, five were only partially compliant (average usage of 13 nights, 2.9 hours per night, and 34 could not comply with it. In all patients who slept with it, the efficacy (assessed by residual AHI derived from the CPAP device was good with an AHI of less than 8/hour. Interestingly, the required optimal pressure decreased from an average of 9.3 cmH2O to 4.6 cmH2O. The SomnuSeal oral interface is effective and may result in converting noncompliant untreated patients with OSA into well-treated ones.

  13. The SomnuSeal Oral Mask Is Reasonably Tolerated by Otherwise CPAP Noncompliant Patients with OSA.

    Science.gov (United States)

    Katz, N; Adir, Y; Etzioni, T; Kurtz, E; Pillar, G

    2013-01-01

    Compliance with CPAP is the major limiting factor in treating patients with OSA. The novel SomnuSeal mask is an oral self-adaptable mask located between the teeth and the lips ensuring that there are no air leaks or skin abrasions. Fifty patients with AHI > 20, who failed previous CPAP trials, were asked to sleep with the mask for one month. In all patients, the mask was connected to an AutoPAP machine with a heated humidifier. Efficacy, convenience, and compliance (average usage for 4 or more hours per night) were monitored. Fifty patients (41 m and 9 f, mean age 57 ± 12 years, BMI 33.6 ± 4.9 kg/m(2), and AHI 47 ± 23/h) participated. Eleven were classified as compliant (average mask usage of 26 nights, 4.7 hours per night), five were only partially compliant (average usage of 13 nights, 2.9 hours per night), and 34 could not comply with it. In all patients who slept with it, the efficacy (assessed by residual AHI derived from the CPAP device) was good with an AHI of less than 8/hour. Interestingly, the required optimal pressure decreased from an average of 9.3 cmH2O to 4.6 cmH2O. The SomnuSeal oral interface is effective and may result in converting noncompliant untreated patients with OSA into well-treated ones.

  14. Proposal of Histophilus somni gen. nov., sp nov for the three species incertae sedis 'Haemophilus somnus', 'Haemophilus agni' and 'Histophilus ovis'

    DEFF Research Database (Denmark)

    Angen, Øystein; Ahrens, Peter; Kuhnert, P.

    2003-01-01

    previously by DNA-DNA hybridization. These results clearly support the allocation of this species to a novel genus within the family Pasteurellaceae. The phenotypic separation of Histophilus somni gen. nov., sp. nov. from other members of the family can, for most strains, be based on capnophilia, yellowish...

  15. Haemophilus influenzae biotype VIII.

    OpenAIRE

    Sottnek, F O; Albritton, W L

    1984-01-01

    Six Haemophilus influenzae strains could not be classified as biotypes I through VII. The strains were indole, urease, and ornithine decarboxylase negative. We propose that they be classified as biotype VIII, a previously unreported biotype.

  16. Haemophilus segnis endocarditis

    DEFF Research Database (Denmark)

    Bangsborg, Jette Marie; Tvede, M; Skinhøj, P

    1988-01-01

    Haemophilus segnis is a rarely recognised commensal in the oropharynx. We wish to report the first published case of endocarditis caused by H. segnis. The patient, a 76-year-old female did not recover until after 2 courses of ampicillin given for a total of 57 days. In the second course of treatm......Haemophilus segnis is a rarely recognised commensal in the oropharynx. We wish to report the first published case of endocarditis caused by H. segnis. The patient, a 76-year-old female did not recover until after 2 courses of ampicillin given for a total of 57 days. In the second course...

  17. Haemophilus influenzae biotype VII.

    OpenAIRE

    Gratten, M

    1983-01-01

    A hitherto unreported biotype of Haemophilus influenzae is described. The isolate is noncapsulate and fails to decarboxylate ornithine or hydrolyze urea but is a strong indole producer. Its frequency is low. It is suggested that this newly recognized biotype of H. influenzae be designated biotype VII.

  18. Monoclonal antibodies against Haemophilus lipopolysaccharides

    OpenAIRE

    Borrelli, Silvia

    1996-01-01

    The genus Haemophilus comprises a group of gram-negative bacteria with fastidious growthrequirements. Among the Haemophilus species, H. influenzae and H. ducreyi are the mostimportant in human medicine. H. influenzae is a common agent in respiratory tract infections and causes severe diseaseslike bacterial meningitidis, pneumonia, otitis and pericarditis among others. Some strains possess acapsular polysaccharide. Six capsular polysaccharides, designated types a-f, have been defined.Most...

  19. DEVELOPMENT OF A PEROXIDASE-ANTIPEROXIDASE (PAP) TECHNIQUE FOR THE IDENTIFICATION OF HAEMOPHILUS-SOMNUS IN PNEUMONIC CALF LUNGS IN DENMARK

    DEFF Research Database (Denmark)

    Tegtmeier, Conny; Jensen, N.E.; Jensen, H.E.

    1995-01-01

    for the determination of the sensitivity and specificity of antiserum that had been heterologously absorbed with antigens of cross-reacting bacteria, i.e. Pasteurella haemolytica and Pasteurella multocida. None of the antisera reacted with Actinomyces pyogenes. An antiserum raised against somatic antigens of the Danish...

  20. NNDSS - Table II. Giardiasis to Haemophilus influenza

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Giardiasis to Haemophilus influenza - 2017. In this Table, provisional cases of selected notifiable diseases (≥1,000 cases reported during the...

  1. NNDSS - Table II. Giardiasis to Haemophilus influenza

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Giardiasis to Haemophilus influenza - 2014. In this Table, all conditions with a 5-year average annual national total of more than or equals 1,000...

  2. NNDSS - Table II. Giardiasis to Haemophilus influenza

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Giardiasis to Haemophilus influenza - 2018. In this Table, provisional cases of selected notifiable diseases (≥1,000 cases reported during the...

  3. NNDSS - Table II. Giardiasis to Haemophilus influenza

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Giardiasis to Haemophilus influenza - 2016. In this Table, provisional* cases of selected†notifiable diseases (≥1,000 cases reported during the...

  4. NNDSS - Table II. Giardiasis to Haemophilus influenza

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Giardiasis to Haemophilus influenza - 2015.In this Table, provisional cases of selected notifiable diseases (≥1,000 cases reported during the...

  5. Haemophilus influenzae and oxidative stress

    Directory of Open Access Journals (Sweden)

    Alistair eHarrison

    2012-03-01

    Full Text Available Haemophilus influenzae is a commensal of the human upper respiratory tract. H. influenzae can, however, move out of its commensal niche and cause multiple respiratory tract diseases. Such diseases include otitis media in young children, as well as exacerbations of chronic obstructive pulmonary disease, sinusitis, conjunctivitis and bronchitis. During the course of colonization and infection, H. influenzae must withstand oxidative stress generated by multiple reactive oxygen species produced endogenously, by other co-pathogens and by host cells. H. influenzae has therefore evolved multiple mechanisms that protect the cell against oxygen-generated stresses. In this review, we will describe these systems. Moreover, we will compare how H. influenzae obviates the effect of oxidative stress as a necessary phenotype for its roles as both a successful commensal and pathogen, relative to the well-described systems in Escherichia coli.

  6. Haemophilus Influenzae Type B (Hib): Questions and Answers

    Science.gov (United States)

    Q&A Haemophilus influenzae type b (Hib): Questions and Answers information about the disease and vaccines What causes Hib disease? Hib disease is caused by a bacterium, Haemophilus influenzae type b. There are ...

  7. Nicotinamide ribosyl uptake mutants in Haemophilus influenzae.

    Science.gov (United States)

    Herbert, Mark; Sauer, Elizabeta; Smethurst, Graeme; Kraiss, Anita; Hilpert, Anna-Karina; Reidl, Joachim

    2003-09-01

    The gene for the nicotinamide riboside (NR) transporter (pnuC) was identified in Haemophilus influenzae. A pnuC mutant had only residual NR uptake and could survive in vitro with high concentrations of NR, but could not survive in vivo. PnuC may represent a target for the development of inhibitors for preventing H. influenzae disease.

  8. Invasive Disease Caused by Nontypeable Haemophilus Influenzae

    Centers for Disease Control (CDC) Podcasts

    2015-11-12

    Dr. Elizabeth Briere discusses Nontypeable Haemophilus influenzae which causes a variety of infections in children and adults.  Created: 11/12/2015 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 11/17/2015.

  9. Purulent pericarditis caused by Haemophilus parainfluenzae.

    Science.gov (United States)

    Latyshev, Yevgeniy; Mathew, Aswin; Jacobson, Jeffrey M; Sturm, Eron

    2013-01-01

    Bacterial pericarditis is a rare disease in the era of antibiotics. Purulent pericarditis is most often caused by Staphylococcus aureus, Streptococcus pneumoniae, or Haemophilus influenzae. The number of H. parainfluenzae infections has been increasing; in rare cases, it has caused endocarditis. We report a case of purulent pericarditis caused by H. parainfluenzae in a 62-year-old woman who reported a recent upper respiratory tract infection. The patient presented with signs and symptoms of pericardial tamponade. Urgent pericardiocentesis restored her hemodynamic stability. However, within 24 hours, fluid reaccumulation led to recurrent pericardial tamponade and necessitated the creation of a pericardial window. Cultures of the first pericardial fluid grew H. parainfluenzae. Levofloxacin therapy was started, and the patient recovered. Haemophilus parainfluenzae should be considered in a patient who has signs and symptoms of purulent pericarditis. Prompt diagnosis, treatment, and antibiotic therapy are necessary for the patient's survival. To our knowledge, this is the first report of purulent pericarditis caused by H. parainfluenzae.

  10. Protective role of maternal antibodies against Haemophilus parasuis infection.

    Science.gov (United States)

    Solano-Aguilar, G I; Pijoan, C; Rapp-Gabrielson, V; Collins, J; Carvalho, L F; Winkelman, N

    1999-01-01

    To evaluate the impact of maternal antibodies after challenge exposure of baby pigs with a homologous serovar of Haemophilus parasuis. 7 gilts and their litters from a high health status farm. Gilts were vaccinated twice with a commercial bacterin that contained H parasuis serovar 4 and 5 or, as a control, adjuvant only. A group of pigs was also vaccinated similarly before challenge exposure. After early and late challenge exposure at 3 and 4 weeks, respectively, all pigs from vaccinated gilts were evaluated for clinical signs of infection, lesions, and antibody titer. All pigs coming from control gilts had severe signs of H parasuis infection. Macroscopic lesions included polyserositis and pneumonia, and bacteriologic examination confirmed H parasuis as the etiologic agent. Vaccinated pigs born to vaccinated gilts did not have clinical signs of disease. However, some vaccinated pigs born to control gilts had signs of nervous system dysfunction and lameness. There was no difference in lesion scores between early or late challenge exposure, but lesions scores for pigs from vaccinated and control gilts were different (P immune-naive and vaccinated pigs from vaccinated gilts were protected against systemic lesions when challenge exposed with a virulent strain of H parasuis. Vaccination of the gilt and pigs protects the latter from polyserositis, but results are not different from those for nonvaccinated pigs from vaccinated gilts. Maternal antibodies did not seem to interfere with vaccination of pigs at 1 and 3 weeks of age.

  11. Evaluation of new biomarker genes for differentiating Haemophilus influenzae from Haemophilus haemolyticus.

    Science.gov (United States)

    Theodore, M Jordan; Anderson, Raydel D; Wang, Xin; Katz, Lee S; Vuong, Jeni T; Bell, Melissa E; Juni, Billie A; Lowther, Sara A; Lynfield, Ruth; MacNeil, Jessica R; Mayer, Leonard W

    2012-04-01

    PCR detecting the protein D (hpd) and fuculose kinase (fucK) genes showed high sensitivity and specificity for identifying Haemophilus influenzae and differentiating it from H. haemolyticus. Phylogenetic analysis using the 16S rRNA gene demonstrated two distinct groups for H. influenzae and H. haemolyticus.

  12. Haemophilus haemolyticus: A Human Respiratory Tract Commensal to Be Distinguished from Haemophilus influenzae

    DEFF Research Database (Denmark)

    Murphy, T.F.; Brauer, A.L.; Sethi, S.

    2007-01-01

    Background. Haemophilus influenzae is a common pathogen in adults with chronic obstructive pulmonary disease (COPD). In a prospective study, selected isolates of apparent H. influenzae had an altered phenotype. We tested the hypothesis that these variant strains were genetically different from ty...... distinguish H. haemolyticus from H. influenzae. H. haemolyticus is a respiratory tract commensal. The recognition that some strains of apparent H. influenzae are H. haemolyticus substantially strengthens the association of true H. influenzae with clinical infection....

  13. Identifying Haemophilus haemolyticus and Haemophilus influenzae by SYBR Green real-time PCR.

    Science.gov (United States)

    Latham, Roger; Zhang, Bowen; Tristram, Stephen

    2015-05-01

    SYBR Green real time PCR assays for protein D (hpd), fuculose kinase (fucK) and [Cu, Zn]-superoxide dismutase (sodC) were designed for use in an algorithm for the identification of Haemophilus influenzae and H. haemolyticus. When tested on 127 H. influenzae and 60 H. haemolyticus all isolates were identified correctly. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

  14. Cellular fatty acid composition of Haemophilus species, Pasteurella multocida, Actinobacillus Actinomycetemcomitans and Haemophilus vaginalis (Corynebacterium vaginale).

    Science.gov (United States)

    Jantzen, E; Berdal, B P; Omland, T

    1980-04-01

    The fatty acid composition of 35 Haemophilus influenzae strains was found to be grossly similar and characterized by relatively large amounts of 14:0, 3-OH-14:0, 16:1 and 16:0. The three C18 fatty acids 18:2, 18:1 and 18:0 were also present, but in much lower concentrations. This general pattern was also found for most of the other species of Haemophilus examined (H. aegyptius, H. aphrophilus, H. canis, H. gallinarum, H. haemolyticus, and H. parainfluenzae). Small but distinct quantitative discrepancies were detected for H. ducreyi and the haemin-independent species H. paraphrohaemolyticus, H. paraphrophilus and H. suis. Actinobacillus actinomycetemcomitans was found to be indistinguishable from H. influenzae. Pasteurella multocida also exhibited a fatty acid pattern closely related to that of Haemophilus, but could be distinguished by its higher concentration levels of the C18 fatty acids. The fatty acid pattern of H. vaginalis was considerably different from those of the other species examined. This species lacked 3-OH-14:0 and 18:2 and contained small amounts of 14:0 and 16:0, whereas 18:1 and 18:0 were the major constituents.

  15. Haemophilus influenzae as an airborne contamination in child day care centers.

    Science.gov (United States)

    Lis, Danuta O; Górny, Rafał L

    2013-05-01

    The aim of this study was to assess the exposure of children to airborne Haemophilus influenzae in day care centers. Air samples were taken using an Andersen impactor in 32 rooms designed for children stay. The concentrations of airborne bacteria were calculated as colony forming units (CFU) (growing on trypticase soy agar) per cubic meter of air (CFU/m(3)). The compositions of bioaerosol were determined on blood trypticase soy agar and Haemophilus selective agar. Isolated strains were identified using API NH strips and apiweb software. The antibiotic resistance of H influenzae strains was determined by the disk diffusion method. Compared with the proposed criteria for microbiologic quality of indoor air, the rooms were characterized by the very high bacterial contamination of the air. The prevailing component of bacterial aerosol was gram-positive cocci. Airborne H influenzae strains were found in 25% of the investigated rooms and were mostly classified as biotype II (33%). It may be accepted that the exposure to airborne H influenzae is typical of child day care centers in contrast to indoor environments with older population. Child day care center contribute to the expansion of H influenzae in human population via air. Generally, airborne H influenzae isolates from the investigated child day care centers were susceptible to older antibiotics such as ampicillin and amoxicillin-clavulanic acid. Copyright © 2013 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

  16. [Severe Haemophilus influenzae b infection in healthy male adult

    DEFF Research Database (Denmark)

    Vilmar, A.C.; Gjorup, I.; David, Kim Peter

    2008-01-01

    Haemophilus influenzae b (Hib) can be the cause of serious infections, and is mainly observed affecting children and immuno-compromised patients. We report a case of a healthy 49-year old male with a severe Hib infection complicated by septicaemia, meningitis and anuria. The risk of invasive Hib...

  17. Haemophilus influenzae type b pneumonia in Egyptian children ...

    African Journals Online (AJOL)

    Tharwat Deraz

    2012-02-28

    Feb 28, 2012 ... Abstract Haemophilus influenzae (Hi) causes more than 3 million cases of serious disease, mainly meningitis and pneumonia in children less than 5 years old with approximately 386,000 deaths each year worldwide. The presence or absence of a polysaccharide capsule is an important distinguishing.

  18. The costs and benefits of a vaccination programme for Haemophilus ...

    African Journals Online (AJOL)

    Haemophilus influenzae type b (Hib) infection is a major cause of severe bacterial infection in young children in. South Africa and world-wide. These diseases can be prevented by immunisation with conjugate Hib vaccines. In South Africa, unlike some developed countries, Hib vaccines are not part of the routine ...

  19. Haemophilus influenzae type f meningitis in a previously healthy boy

    DEFF Research Database (Denmark)

    Ronit, Andreas; Berg, Ronan M G; Bruunsgaard, Helle

    2013-01-01

    Non-serotype b strains of Haemophilus influenzae are extremely rare causes of acute bacterial meningitis in immunocompetent individuals. We report a case of acute bacterial meningitis in a 14-year-old boy, who was previously healthy and had been immunised against H influenzae serotype b (Hib...

  20. Fimbria-mediated adherence and hemagglutination of Haemophilus influenzae

    NARCIS (Netherlands)

    van Ham, S. M.; van Alphen, L.; Mooi, F. R.

    1992-01-01

    The gram-negative bacterium Haemophilus influenzae expresses morphologically and functionally distinct types of fimbriae, of which the LKP fimbriae mediate hemagglutination and adherence to human epithelial cells but hamper mucosal invasion. Therefore, the both in vivo and in vitro observed fimbrial

  1. Community-acquired Haemophilus influenzae meningitis in adults

    NARCIS (Netherlands)

    Brouwer, M. C.; van de Beek, D.; Heckenberg, S. G. B.; Spanjaard, L.; de Gans, J.

    2007-01-01

    Haemophilus influenzae is an uncommon cause of bacterial meningitis in adults. This report describes a prospective evaluation of 16 episodes of community-acquired H. influenzae meningitis in a nationwide study on bacterial meningitis. Predisposing conditions were present in eight (50%) of the 16

  2. Haemophilus influenzae type b pneumonia in Egyptian children ...

    African Journals Online (AJOL)

    Haemophilus influenzae (Hi) causes more than 3 million cases of serious disease, mainly meningitis and pneumonia in children less than 5 years old with approximately 386,000 deaths each year worldwide. The presence or absence of a polysaccharide capsule is an important distinguishing characteristic of H. influenzae ...

  3. The costs and benefits of a vaccination programme for Haemophilus ...

    African Journals Online (AJOL)

    Haemophilus influenzae type b (Hib) infection is a major cause of severe bacterial infection in young children in South Africa and world-wide. These diseases can be prevented by immunisation with conjugate Hib vaccines. In South Africa, unlike some developed countries, Hib vaccines are not part of the routine ...

  4. Safety and immunogenicity of two Haemophilus influenzae type b ...

    African Journals Online (AJOL)

    Objectives. Haemophilus influenzae type b (Hib) infection remains a major public health problem inthe developing world. We evaluated the safety and immunogenicity of a new PRP-CRM197 conjugate Hib vaccine (Vaxem Hib, Chiron Vacdnes), compared with theHibTITER vaccine (WyethLederle Vaccines), following the ...

  5. To tilfaelde af invasive infektioner med Haemophilus influenzae type f

    DEFF Research Database (Denmark)

    Nielsen, Jette Dettmann; Lind, Jens Wentzel; Bruun, Britta

    2009-01-01

    Two cases of invasive Haemophilus influenzae type f infection are presented: a three-week-old boy with meningitis and a 62-year-old woman with arthritis and bacteremia. Since 1993 vaccination against H. influenzae type b (Hib) has been offered to Danish children. The result has been a remarkable...

  6. [Two cases of invasive Haemophilus influenzae type f infection

    DEFF Research Database (Denmark)

    Nielsen, J.D.; Lind, J.W.; Bruun, B.

    2009-01-01

    Two cases of invasive Haemophilus influenzae type f infection are presented: a three-week-old boy with meningitis and a 62-year-old woman with arthritis and bacteremia. Since 1993 vaccination against H. influenzae type b (Hib) has been offered to Danish children. The result has been a remarkable...

  7. Molecular basis of antimicrobial resistance in non-typable Haemophilus influenzae.

    Science.gov (United States)

    Sánchez, L; Leranoz, S; Puig, M; Lorén, J G; Nikaido, H; Viñas, M

    1997-09-01

    Strains of the facultative anaerobe Haemophilus influenzae, both type b and non typable strains, are frequently multiresistant. The measurement of the antibiotic permeability of Haemophilus influenzae outer membrane (OM) shows that antibiotics can cross through the OM easily. Thus, enzymatic activity or efflux pumps could be responsible for multiresistance. An efflux system closely related to AcrAB of Escherichia coli is present in Haemophilus influenzae. However, their role in multiresistance seems irrelevant. Classical mechanisms such as plasmid exchange seems to be playing a major role in the multidrug resistance in Haemophilus influenzae.

  8. In vitro evaluation of nicotinamide riboside analogs against Haemophilus influenzae.

    OpenAIRE

    Godek, C P; Cynamon, M H

    1990-01-01

    Exogenous NAD, nicotinamide mononucleotide, or nicotinamide riboside is required for the growth of Haemophilus influenzae. These compounds have been defined as the V-factor growth requirement. We have previously shown that the internalization of nicotinamide riboside is energy dependent and carrier mediated with saturation kinetics. Thionicotinamide riboside, 3-pyridinealdehyde riboside, 3-acetylpyridine riboside, and 3-aminopyridine riboside were prepared from their corresponding NAD analogs...

  9. Meningitis y artritis por Haemophilus influenzae en un adulto

    Directory of Open Access Journals (Sweden)

    Javier Molina

    1988-02-01

    Full Text Available Tradicionalmente el Haemophilus influenzae ha sido considerado un germen causante de infecciones en niños; en adultos se lo ha relacionado con Infecciones respiratorias, pero en los últimos tiempos se han descrito en ellos infecciones severas cuando hay algunos factores predisponentes. Se describe un paciente drogadicto de 30 años con cuadro de meningitis y artritis y prueba de látex y cultivo de LCR positivos para HaemophiIus influenzae, quien recibió tratamiento con ampicilina, 2 gramos Intravenosos cada 4 horas y evolucionó a la mejoría sin secuelas. Se plantea la necesidad de tener en cuenta al Haemophilus influenzae como patógeno del adulto y más en aquellas personas con factores predisponentes.

    Haemophilus influenzae has traditionally been considered as an infectious agent that predominantly affects children; instead, in adults It has been Linked either to respiratory infections or to gevere infections occurring when predisposing factors are present. We describe a 30 year-old drug adict patient that presented with meningitis and arthritis; both latex test and cerebrospinal fluid culture were positive for Haemophilus influenzae. He was treated with ampicilin 2 gm, I. V. every four hours and improved without sequelae. This microorganism must be considered among those affecting adult patients specially when predisposing factors for infection are present.

  10. 21 CFR 522.955 - Florfenicol.

    Science.gov (United States)

    2010-04-01

    ... treatment of bovine respiratory disease (BRD) associated with Mannheimia haemolytica, Pasteurella multocida.... For treatment of BRD associated with Mannheimia (Pasteurella) haemolytica, P. multocida, and... Mannheimia (Pasteurella) haemolytica, P. multocida, and Haemophilus somnus. (C) Limitations. Do not slaughter...

  11. Genome Sequences for Five Strains of the Emerging Pathogen Haemophilus haemolyticus

    Science.gov (United States)

    Jordan, I. King; Conley, Andrew B.; Antonov, Ivan V.; Arthur, Robert A.; Cook, Erin D.; Cooper, Guy P.; Jones, Bernard L.; Knipe, Kristen M.; Lee, Kevin J.; Liu, Xing; Mitchell, Gabriel J.; Pande, Pushkar R.; Petit, Robert A.; Qin, Shaopu; Rajan, Vani N.; Sarda, Shruti; Sebastian, Aswathy; Tang, Shiyuyun; Thapliyal, Racchit; Varghese, Neha J.; Ye, Tianjun; Katz, Lee S.; Wang, Xin; Rowe, Lori; Frace, Michael; Mayer, Leonard W.

    2011-01-01

    We report the first whole-genome sequences for five strains, two carried and three pathogenic, of the emerging pathogen Haemophilus haemolyticus. Preliminary analyses indicate that these genome sequences encode markers that distinguish H. haemolyticus from its closest Haemophilus relatives and provide clues to the identity of its virulence factors. PMID:21952546

  12. Identification and partial characterization of acid phosphatases from Haemophilus parasuis

    OpenAIRE

    Manrique Ramírez, Paula Constanza

    2014-01-01

    Haemophilus parasuis es una bacteria Gram negativa común en el tracto respiratorio superior de cerdos sanos y es el agente etiológico de la enfermedad de Glässer, que se caracteriza por poliserositis fibrinosa y poliartritis. En los últimos años, la prevalencia de las infecciones respiratorias, incluyendo la producida por H. parasuis, ha aumentado debido a prácticas de manejo de los animales, como el destete precoz, y a la aparición de virus inmunosupresores. Poco se sabe acerca de la patogén...

  13. Haemophilus influenzae: a forgotten cause of neonatal sepsis?

    Science.gov (United States)

    Dobbelaere, A; Jeannin, P; Bovyn, T; Ide, L

    2015-06-01

    Due to the introduction of the conjugate vaccine against serotype b, neonatal sepsis caused by Haemophilus influenzae became very rare. There is little data in Belgium concerning the prevalence of H. influenzae early onset neonatal sepsis and articles about neonatal sepsis and H. influenzae published in the last decade are scarce. We report two invasive infections with a non-typeable H. influenzae. These cases show that neonatal sepsis caused by non-typeable H. influenzae may be underestimated and we believe that there is need for a better registration of this kind of infection.

  14. Polymicrobial infective endocarditis caused by Neisseria sicca and Haemophilus parainfluenzae

    Directory of Open Access Journals (Sweden)

    Nikoloz Koshkelashvili

    2016-01-01

    Full Text Available Infective endocarditis is a common clinical problem in industrialized countries. Risk factors include abnormal cardiac valves, a history of endocarditis, intracardiac devices, prosthetic valves and intravenous drug use. We report a case of polymicrobial infective endocarditis in a 33 year-old female with a history chronic heroin use caused by Neisseria sicca and Haemophilus parainfluenzae. We believe the patient was exposed to these microbes by cleansing her skin with saliva prior to injection. Pairing a detailed history with the consideration of atypical agents is crucial in the proper diagnosis and management of endocarditis in patients with high-risk injection behaviors.

  15. The Immunostimulatory Capacity of Nontypeable Haemophilus influenzae Lipooligosaccharide

    Directory of Open Access Journals (Sweden)

    Gabrielle N. Gaultier

    2017-02-01

    Full Text Available Background: We have recently found that lipooligosaccharide (LOS isolated from encapsulated strains of Haemophilus influenzae (H. influenzae has strong adjuvant, but diminished pro-inflammatory ability as compared to Escherichia coli lipopolysaccharide (LPS. In this study, we aimed to determine the immunostimulatory capacity of nontypeable/ non-encapsulated H. influenzae (NTHi LOS by comparing the effect of killed bacteria with LOS isolated from the same strain. Methods: Following stimulation of human monocytic THP-1 cells with killed NTHi strain 375, or with the corresponding amount of LOS, we studied the protein and gene expression of immunostimulatory and antigen-presenting molecules, cytokines, and innate immune receptors. Results: Stimulation with LOS resulted in lower expression of adhesion (CD54, CD58 as well as costimulatory molecules (CD40, CD86, but in higher expression of antigen-presenting molecules (HLA-DR and HLA-ABC compared to killed NTHi, whereas killed bacteria induced higher release of both TNF-α and IL-10. The results indicate that while LOS of NTHi has decreased capacity to induce pro-inflammatory responses compared to E. coli LPS or killed NTHi, this LOS has the potential to facilitate antigen presentation. Conclusions: Considering the important role of NTHi as a respiratory pathogen, and its currently increasing significance in the etiology of invasive infections, LOS deserves further attention as a vaccine antigen, which also has potent adjuvant properties. Keywords: Nontypeable Haemophilus influenzae, Lipooligosaccharide, THP-1 cells, innate immune responses

  16. Heavy-chain isotype patterns of human antibody-secreting cells induced by Haemophilus influenzae type b conjugate vaccines in relation to age and preimmunity

    DEFF Research Database (Denmark)

    Barington, T; Juul, Lars; Gyhrs, A

    1994-01-01

    The influence of preexisting immunity on the heavy-chain isotypes of circulating antibody-secreting cells (AbSC) induced by vaccination with Haemophilus influenzae type b (Hib) capsular polysaccharide (HibCP) coupled to tetanus toxoid (TT) or diphtheria toxoid (DT) and by vaccination with TT or DT...... of natural HibCP antibodies (r = 0.59; P = 0.00002). A possible role of natural exposure for Hib or cross-reactive bacteria on the mucosal surfaces in the shaping of the isotype response to HibCP conjugate vaccines is discussed....

  17. Tricuspid valve endocarditis caused by Haemophilus parainfluenzae: a case report and review of the literature.

    Science.gov (United States)

    Nwaohiri, Nnamdi; Urban, Carl; Gluck, Jason; Ahluwalia, Maneesha; Wehbeh, Wehbeh

    2009-06-01

    Haemophilus parainfluenzae is a Gram-negative bacterium that is often difficult to isolate and identify. We report a rare case of tricuspid valve and pacemaker endocarditis caused by this organism and explore factors related to etiopathogenesis, prevention, and treatment.

  18. Transfer of plasmid-mediated ampicillin resistance from Haemophilus to Neisseria gonorrhoeae requires an intervening organism.

    Science.gov (United States)

    McNicol, P J; Albritton, W L; Ronald, A R

    1986-01-01

    Haemophilus species have been implicated as the source of plasmid-mediated ampicillin resistance in Neisseria gonorrhoeae. Previous attempts to transfer conjugally the resistance plasmids from Haemophilus species to N. gonorrhoeae have met with limited success. Using both biparental and triparental mating systems, it was found that transfer will occur if the commensal Neisseria species, Neisseria cinerea, is used as a transfer intermediate. This organism stably maintains resistance plasmids of Haemophilus and facilitates transfer of these plasmids to N. gonorrhoeae, in a triparental mating system, at a transfer frequency of 10(-8). Both Haemophilus ducreyi and N. gonorrhoeae carry mobilizing plasmids capable of mediating conjugal transfer of the same resistance plasmids. However, restriction endonuclease mapping and DNA hybridization studies indicate that the mobilizing plasmids are distinctly different molecules. Limited homology is present within the transfer region of these plasmids.

  19. Antimicrobial susceptibility of Haemophilus parasuis and Histophilus somni from pigs and cattle in Denmark

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Seyfarth, Anne Mette; Angen, Øystein

    2004-01-01

    A total of 52 Haemophilus parasuis and 80 Histophilus somni isolates were tested for antimicrobial susceptibility by MIC-determinations. None of the isolates were resistant to ampicillin, ceftiofur, ciprofloxacin, erythromycin, florphenicol, penicillin, spectinomycin, tetracycline, tiamulin...

  20. Vaccine development for protection against systemic infections with Streptococcus suis and Haemophilus parasuis in swine

    Science.gov (United States)

    Both Streptococcus suis and Haemophilus parasuis are important invasive bacterial pathogens of swine, commonly causing meningitis, arthritis, polyserositis, and septicemia. Due to the presence of many serotypes and high genotypic variability, efficacious vaccines are not readily available. We are us...

  1. Onderzoek naar de gevoeligheid van streptococcus pneumoniae, haemophilus influenzae en Moraxella catarrhalis voor antibiotica

    NARCIS (Netherlands)

    de Neeling AJ; Overbeek BP; Timmerman CP; de Jong J; Dessens-Kroon M; van Klingeren B

    1992-01-01

    The susceptibility to antibiotics of three respiratory pathogens, Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis, was determined. The isolates were obtainied in three regional laboratories in the Netherlands and tested using the microdilution method. After incubation

  2. Increased Sensitivity of a New Coagglutination Test for Rapid Identification of Haemophilus influenzae Type b

    OpenAIRE

    Grasso, Robert J.; West, Loyd A.; Holbrook, Nikki J.; Halkias, Demetrios G.; Paradise, Lois J.; Friedman, Herman

    1981-01-01

    A newly developed rapid coagglutination test for identifying Haemophilus influenzae type b organisms isolated from clinical specimens correlated 100% with the slide agglutination test but was 100- to 200-fold more sensitive.

  3. [Effect of ambroxol on biofilm of Haemophilus influenzae and bactericidal action].

    Science.gov (United States)

    Gao, Xue; Zhang, Yutuo; Lin, Yantao; Li, Haifeng; Xin, Yunchao; Zhang, Xiaolei; Xu, Yunpeng; Shang, Xiaoling

    2014-05-01

    To establish a biofilm model of Haemophilus influenzae and observe the effect of ambroxol on biofilm of Haemophilus influenzae and bactericidal action. Thirty strains of Haemophilus influenzae were isolated from adenoids of children with adenoidal hypertrophy. Two strains which could build stronger biofilms was selected in a 96-well plate. The effect of ambroxol on biofilms were determined by crystal violet, and the structure of biofilms were observed by scanning electron microscope (SEM). The numbers of viable bacterial in biofilm after ambroxol treatmented determined by plate culture count. Through crystal violet assay, significant difference (P ambroxol concentration reached at 0.25 mg/ml and 0.49 mg/ml. The biofilms was destroyed by SEM. Ambroxol had the positive effect on bacterial killing by plate culture count,and the effect was in a dose dependent. Ambroxol could destroy the biofilm of Haemophilus influenzae, and had bactericidal function in vitro.

  4. Nontypeable Haemophilus influenzae in chronic obstructive pulmonary disease and lung cancer

    Directory of Open Access Journals (Sweden)

    Seyed Javad Moghaddam

    2011-01-01

    Full Text Available Seyed Javad Moghaddam1, Cesar E Ochoa1,2, Sanjay Sethi3, Burton F Dickey1,41Department of Pulmonary Medicine, the University of Texas MD Anderson Cancer Center, Houston, TX, USA; 2Tecnológico de Monterrey School of Medicine, Monterrey, Nuevo León, Mexico; 3Department of Medicine, University at Buffalo, State University of New York, Buffalo, NY, USA; 4Center for Inflammation and Infection, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX, USAAbstract: Chronic obstructive pulmonary disease (COPD is predicted to become the third leading cause of death in the world by 2020. It is characterized by airflow limitation that is not fully reversible. The airflow limitation is usually progressive and associated with an abnormal inflammatory response of the lungs to noxious particles and gases, most commonly cigarette smoke. Among smokers with COPD, even following withdrawal of cigarette smoke, inflammation persists and lung function continues to deteriorate. One possible explanation is that bacterial colonization of smoke-damaged airways, most commonly with nontypeable Haemophilus influenzae (NTHi, perpetuates airway injury and inflammation. Furthermore, COPD has also been identified as an independent risk factor for lung cancer irrespective of concomitant cigarette smoke exposure. In this article, we review the role of NTHi in airway inflammation that may lead to COPD progression and lung cancer promotion.Keywords: COPD, NTHi, inflammation

  5. Structure and function of the Haemophilus influenzae autotransporters

    Directory of Open Access Journals (Sweden)

    Nicole A Spahich

    2011-09-01

    Full Text Available Autotransporters are a large class of proteins that are found in the outer membrane of gram-negative bacteria and are almost universally implicated in virulence. These proteins consist of a C-terminal β-domain that is embedded in the outer membrane and an N-terminal domain that is exposed on the bacterial surface and is endowed with effector function. In this article, we review and compare the structural and functional characteristics of the Haemophilus influenzae IgA1 protease and Hap monomeric autotransporters and the H. influenzae Hia and Hsf trimeric autotransporters. All of these proteins play a role in colonization of the upper respiratory tract and in the pathogenesis of H. influenzae disease.

  6. A comparative study of preservation and storage of Haemophilus influenzae

    Directory of Open Access Journals (Sweden)

    Olga C Aulet de Saab

    2001-05-01

    Full Text Available The aim of this study was to compare the efficacy of conservation by freezing the strains of Haemophilus influenzae at -20ºC and -70ºC. Skim milk supplemented with glucose, yeast extract and glycerol allowed highest viability of H. influenzae both at -20ºC and -70ºC from the media analyzed. Trypticase soy broth and brain heart infusion broth supplemented with glycerol, allowed excellent recovery. Use of cotton swaps as supporting material, with or without addition of cryoprotective agents, did not modify H. influenzae viability after six months of storage. Concentration of the initial inoculum positively affected viability when stored at -20ºC. Initial concentration did not influence survival after storage at -70ºC. Thawing at room temperature should not exceed 3 h as to get highest survival percentage.

  7. Non-Type B Haemophilus Influenzae Meningitis: A Case Report

    Directory of Open Access Journals (Sweden)

    Fatma Deniz Aygun

    2016-02-01

    Full Text Available Haemophilus influenza is one of the most common cause of bacterial meningitis in children. H.influenzae, especially type b (Hib serotype causes invasive infections in children under five years of age. The widespread use of Hib conjugate vaccines has led to a dramatic decline in the incidence of invasive Hib infections. But, the invasive diseases are still reported, particularly nontypeable H. influenzae (noncapsulated remain as an important pathogen. However, there is no evidence that nontypeable H. influenzae infections have increased in frequency. Nontypeable H. Ižnfluenzae serotype is encountered as a cause of acute bacterial meningitis among all ages. In this paper, we present to draw attention to the causative bacterium, in a case of bacterial meningitis caused by nontypeable H. influenzae infection in a child immunized with Hib vaccine.

  8. Restriction enzyme analysis of plasmids from Haemophilus influenzae.

    Science.gov (United States)

    Harkess, N K; Murray, M L

    1978-05-01

    Examination of Haemophilus influenzae strains isolated in New Orleans revealed ampicillin-resistant strains with plasmids of size classes not previously detected in North America. The molecular weight of plasmids in five ampicillin-resistant strains ranged from 0.8 x 10(6) daltons (0.8 Mdal) to 36 Mdal. The molecular weights of the plasmids were determined by sucrose gradient centrifugation, electron microscopy, and agarose gel electrophoresis. Plasmids of the previously detected 30-Mdal size class were found in three of the five ampicillin-resistant strains. Restriction enzyme analysis is consistent with a close relationship between these three 30-Mdal plasmids. Of the two remaining ampicillin-resistant strains, one contained a single plasmid of 36 Mdal and the other contained two plasmids of 0.8 and 2.3 Mdal.

  9. Haemophilus haemolyticus interaction with host cells is different to nontypeable Haemophilus influenzae and prevents NTHi association with epithelial cells

    Directory of Open Access Journals (Sweden)

    Janessa Lea Pickering

    2016-05-01

    Full Text Available Nontypeable Haemophilus influenzae (NTHi is an opportunistic pathogen that resides in the upper respiratory tract and contributes to a significant burden of respiratory related diseases in children and adults. Haemophilus haemolyticus is a respiratory tract commensal that can be misidentified as NTHi due to high levels of genetic relatedness. There are reports of invasive disease from H. haemolyticus, which further blurs the species boundary with NTHi. To investigate differences in pathogenicity between these species, we optimized an in vitro epithelial cell model to compare the interaction of 10 H. haemolyticus strains with 4 NTHi and 4 H. influenzae-like haemophili. There was inter- and intra-strain variability but overall, H. haemolyticus had reduced capacity to attach to and invade nasopharyngeal and bronchoalveolar epithelial cell lines (D562 and A549 within 3h when compared with NTHi. H. haemolyticus was cytotoxic to both cell lines at 24h, whereas NTHi was not. Nasopharyngeal epithelium challenged with some H. haemolyticus strains released high levels of inflammatory mediators IL-6 and IL-8, whereas NTHi did not elicit an inflammatory response despite higher levels of cell association and invasion. Furthermore, peripheral blood mononuclear cells stimulated with H. haemolyticus or NTHi released similar and high levels of IL-6, IL-8, IL-10, IL-1β and TNFα when compared with unstimulated cells but only NTHi elicited an IFNγ response.Due to the relatedness of H. haemolyticus and NTHi, we hypothesized that H. haemolyticus may compete with NTHi for colonization of the respiratory tract. We observed that in vitro pre-treatment of epithelial cells with H. haemolyticus significantly reduced NTHi attachment, suggesting interference or competition between the two species is possible and warrants further investigation. In conclusion, H. haemolyticus interacts differently with host cells compared to NTHi, with different immunostimulatory and

  10. Map-Based Comparative Genomic Analysis of Virulent Haemophilus Parasuis Serovars 4 and 5

    OpenAIRE

    Lawrence, Paulraj; Bey, Russell

    2015-01-01

    Haemophilus parasuis is a commensal bacterium of the upper respiratory tract of healthy pigs. However, in conjunction with viral infections in immunocompromised animals H. parasuis can transform into a pathogen that is responsible for causing Glasser's disease which is typically characterized by fibrinous polyserositis, polyarthritis, meningitis and sometimes acute pneumonia and septicemia in pigs. Haemophilus parasuis serovar 5 is highly virulent and more frequently isolated from respiratory...

  11. Endocardite infecciosa por Haemophilus aphrophilus: relato de caso Infective endocarditis due to Haemophilus aphrophilus: a case report

    Directory of Open Access Journals (Sweden)

    Ricardo M. Pereira

    2008-04-01

    Full Text Available OBJETIVO: Descrever o caso de uma criança com endocardite infecciosa causada por Haemophilus aphrophilus. DESCRIÇÃO: Menino com febre e calafrios há 20 dias. À internação, apresentava-se febril, descorado e sem sinais de instabilidade hemodinâmica; à ausculta cardíaca, tinha sopro holosistólico em foco mitral. Os exames laboratoriais identificaram anemia (hemoglobina = 9,14 g/dL, leucócitos totais de 11.920 mm³, plaquetas de 250.000 mm³, velocidade de sedimentação das hemácias e proteína C reativa elevadas. O ecocardiograma revelou imagem em válvula mitral, sugestiva de vegetação. Com a hipótese de endocardite, foi iniciada antibioticoterapia com penicilina cristalina (200.000 UI/kg/dia associada à gentamicina (4 mg/kg/dia. No terceiro dia de tratamento, foi identificado Haemophilus aphrophilus em hemoculturas, sendo então trocado o esquema antibiótico para ceftriaxona (100 mg/kg/dia. No 20º dia de internação, encontrava-se pálido, mas sem febre e sem outras queixas. Os exames mostravam hemoglobina = 7,0 g/dL, leucócitos = 2.190 mm³, plaquetas = 98.000 mm³, razão normatizada internacional = 1,95 e R = 1,89. Foi feita hipótese de reação adversa ao ceftriaxona, que foi substituído por ciprofloxacina, 20 mg/kg/dia, até completar 6 semanas de tratamento. Após 72 horas da troca, houve normalização dos exames. Durante seguimento ambulatorial, apresentou insuficiência mitral grave, sendo submetido a troca de válvula por prótese metálica 9 meses após quadro agudo. Há 3 anos encontra-se bem, em acompanhamento ambulatorial. COMENTÁRIOS: É rara a identificação de agentes do grupo HACEK (Haemophilus ssp, Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens e Kingella kingae em crianças com endocardite infecciosa. O caso apresentado, sem fatores de risco relacionados a esses agentes, reafirma a necessidade de tentar sempre identificar o agente etiológico das endocardites para

  12. Experimental infections of mice and guinea pigs with Haemophilus parasuis.

    Science.gov (United States)

    Morozumi, T; Hiramune, T; Kobayashi, K

    1982-01-01

    The pathogenicity of Haemophilus parasuis for mice and guinea pigs was examined. Mice were inoculated intraperitoneally with 2 X 10(7) to 2 X 10(9) organisms suspended in saline or in broth containing fresh yeast extract. Most of them survived after inoculation. Death occurred only in mice inoculated with 2 X 10(9) organisms suspended in broth. The recovery rate of H. parasuis from all the dead mice varied from 28.9% of the brains to 71.4% of the lungs. There were no lesions observed in any mouse, except one. Guinea pigs were inoculated intraperitoneally with 1 X 10(8) to 1.6 X 10(10) organisms suspended in saline. Many of them died after showing septicemia and serofibrinous serositis, which were associated with purulent leptomeningitis or meningoencephalitis in some of them. H. parasuis was recovered abundantly from many organs, including the brain, in the guinea pigs. It was also recovered from guinea pigs inoculated with 1.8 X 10(9) organisms by various routes. Serositis was observed in guinea pigs inoculated intramuscularly or intrapulmonarily. These results suggested that guinea pigs might be available for investigation of the pathogenicity of H. parasuis.

  13. Purification and renaturation of membrane neuraminidase from Haemophilus parasuis.

    Science.gov (United States)

    Lichtensteiger, Carol A; Vimr, Eric R

    2003-05-02

    Haemophilus parasuis, which causes polyserositis, polysynovitis, meningitis, septicemia, and pneumonia in pigs, has emerged as an increasing problem in modern swine production systems. Co-factors for and the pathogenesis of H. parasuis disease are not defined. One of the potential virulence factors of H. parasuis is its neuraminidase (sialidase). While purifying the H. parasuis neuraminidase from the membrane fraction, we developed a protocol to renature enzymatic activity after enzyme preparations were resolved electrophorectically in denaturing polyacrylamide gels. The H. parasuis neuraminidase co-resolved with recombinant neuraminidase of Vibrio cholera; thus its apparent molecular mass is 82 kilodalton (kDa). The H. parasuis neuraminidase was associated with the membrane fraction and the purification protocol removed over 99% of the H. parasuis cell protein while retaining over 90% of the neuraminidase activity. Purified protein will provide another avenue to clone the neuraminidase gene that has been refractory to cloning and the protocol will be a means to purify recombinant protein. Copyright 2003 Elsevier Science B.V.

  14. In vitro evaluation of nicotinamide riboside analogs against Haemophilus influenzae.

    Science.gov (United States)

    Godek, C P; Cynamon, M H

    1990-08-01

    Exogenous NAD, nicotinamide mononucleotide, or nicotinamide riboside is required for the growth of Haemophilus influenzae. These compounds have been defined as the V-factor growth requirement. We have previously shown that the internalization of nicotinamide riboside is energy dependent and carrier mediated with saturation kinetics. Thionicotinamide riboside, 3-pyridinealdehyde riboside, 3-acetylpyridine riboside, and 3-aminopyridine riboside were prepared from their corresponding NAD analogs. These compounds and several other nicotinamide riboside analogs were evaluated for their ability to support the growth of H. influenzae and for their ability to block the uptake of [carbonyl-14C]nicotinamide riboside by H. influenzae. 3-Aminopyridine riboside blocked the uptake of [carbonyl-14C]nicotinamide riboside and inhibited the growth of H. influenzae when NAD, nicotinamide mononucleotide, or nicotinamide riboside served as the V factor. The antibacterial activity of 3-aminopyridine riboside was found to be specific for H. influenzae but had no effect on the growth of Staphylococcus aureus or Escherichia coli. In additional experiments by reversed-phase high-performance liquid chromatography, it was determined that whole cells of H. influenzae degrade 3-aminopyridine adenine dinucleotide to 3-aminopyridine riboside, which is then internalized. Inside the cell, 3-aminopyridine riboside has the ability to interfere with the growth of H. influenzae by an undetermined mechanism.

  15. Vaccines for Nontypeable Haemophilus influenzae: the Future Is Now.

    Science.gov (United States)

    Murphy, Timothy F

    2015-05-01

    Infections due to nontypeable Haemophilus influenzae result in enormous global morbidity in two clinical settings: otitis media in children and respiratory tract infections in adults with chronic obstructive pulmonary disease (COPD). Recurrent otitis media affects up to 20% of children and results in hearing loss, delays in speech and language development and, in developing countries, chronic suppurative otitis media. Infections in people with COPD result in clinic and emergency room visits, hospital admissions, and respiratory failure. An effective vaccine would prevent morbidity, help control health care costs, and reduce antibiotic use, a major contributor to the global crisis in bacterial antibiotic resistance. The widespread use of the pneumococcal conjugate vaccines is causing a relative increase in H. influenzae otitis media. The partial protection against H. influenzae otitis media induced by the pneumococcal H. influenzae protein D conjugate vaccine represents a proof of principle of the feasibility of a vaccine for nontypeable H. influenzae. An ideal vaccine antigen should be conserved among strains, have abundant epitopes on the bacterial surface, be immunogenic, and induce protective immune responses. Several surface proteins of H. influenzae have been identified as potential vaccine candidates and are in various stages of development. With continued research, progress toward a broadly effective vaccine to prevent infections caused by nontypeable H. influenzae is expected over the next several years. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  16. Pediatric orbital cellulitis in the Haemophilus influenzae vaccine era.

    Science.gov (United States)

    Sharma, Abhishek; Liu, Eugene S; Le, Tran D; Adatia, Feisal A; Buncic, J Raymond; Blaser, Susan; Richardson, Susan

    2015-06-01

    To evaluate the microbiology of pediatric orbital cellulitis in blood cultures and abscess drainage cultures following the introduction of the Haemophilus influenzae serotype b (Hib) vaccine. The medical records of all pediatrics patients (aged orbital imaging querying "orbital cellulitis," "periorbital cellulitis," "preseptal cellulitis," or "post-septal cellulitis" were retrospectively reviewed. The records, microbiology, and radiology of these patients were reviewed to assess the rates and complications of H. influenzae orbital cellulitis, including bacteremia and meningitis. A total of 149 patients were diagnosed with preseptal or orbital cellulitis, of whom 101 (mean age, 7.2 ± 4.0) had true orbital cellulitis. No patients grew H. influenzae from blood cultures. Of the 101 patients, 30 (29.7%) required surgical drainage and had abscess drainage fluid sent for microbiology. Of these, 18 (64.3%) had a positive culture: 4 (13.3%) grew H. influenzae from their abscess drainage fluid samples; 1 grew H. influenzae alone; and 3 had mixed growth that included H. influenzae. The patients positive for H. influenzae were significantly older and had significantly larger abscesses. Although there were no cases of H. influenzae bacteremia or meningitis in our cases of orbital cellulitis, abscess drainage fluid microbiology indicated that H. influenzae remains a cause of orbital cellulitis. H. influenzae abscess volume was significantly larger than other bacterial abscesses and was associated with abscesses of mixed bacterial growth in older children. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

  17. Transformation of natural genetic variation into Haemophilus influenzae genomes.

    Directory of Open Access Journals (Sweden)

    Joshua Chang Mell

    2011-07-01

    Full Text Available Many bacteria are able to efficiently bind and take up double-stranded DNA fragments, and the resulting natural transformation shapes bacterial genomes, transmits antibiotic resistance, and allows escape from immune surveillance. The genomes of many competent pathogens show evidence of extensive historical recombination between lineages, but the actual recombination events have not been well characterized. We used DNA from a clinical isolate of Haemophilus influenzae to transform competent cells of a laboratory strain. To identify which of the ~40,000 polymorphic differences had recombined into the genomes of four transformed clones, their genomes and their donor and recipient parents were deep sequenced to high coverage. Each clone was found to contain ~1000 donor polymorphisms in 3-6 contiguous runs (8.1±4.5 kb in length that collectively comprised ~1-3% of each transformed chromosome. Seven donor-specific insertions and deletions were also acquired as parts of larger donor segments, but the presence of other structural variation flanking 12 of 32 recombination breakpoints suggested that these often disrupt the progress of recombination events. This is the first genome-wide analysis of chromosomes directly transformed with DNA from a divergent genotype, connecting experimental studies of transformation with the high levels of natural genetic variation found in isolates of the same species.

  18. Assessing the antibiotic potential of essential oils against Haemophilus ducreyi.

    Science.gov (United States)

    Lindeman, Zachary; Waggoner, Molly; Batdorff, Audra; Humphreys, Tricia L

    2014-05-27

    Haemophilus ducreyi is the bacterium responsible for the genital ulcer disease chancroid, a cofactor for the transmission of HIV, and it is resistant to many antibiotics. With the goal of exploring possible alternative treatments, we tested essential oils (EOs) for their efficacy as antimicrobial agents against H. ducreyi. We determine the minimum inhibitory concentration (MIC) of Cinnamomum verum (cinnamon), Eugenia caryophyllus (clove) and Thymus satureioides (thyme) oil against 9 strains of H. ducreyi using the agar dilution method. We also determined the minimum lethal concentration for each oil by subculturing from the MIC plates onto fresh agar without essential oil. For both tests, we used a 2-way ANOVA to evaluate whether antibiotic-resistant strains had a different sensitivity to the oils relative to non-resistant strains. All 3 oils demonstrated excellent activity against H. ducreyi, with MICs of 0.05 to 0.52 mg/mL and MLCs of 0.1-0.5 mg/mL. Antibiotic-resistant strains of H. ducreyi were equally susceptible to these 3 essential oils relative to non-resistant strains (p=0.409). E. caryophyllus, C. verum and T. satureioides oils are promising alternatives to antibiotic treatment for chancroid.

  19. Characterization of an 18,000-molecular-weight outer membrane protein of Haemophilus ducreyi that contains a conserved surface-exposed epitope.

    Science.gov (United States)

    Spinola, S M; Griffiths, G E; Bogdan, J; Menegus, M A

    1992-02-01

    Identification of antigenically conserved surface components of Haemophilus ducreyi may facilitate the development of reagents to diagnose and prevent chancroid. A hybridoma derived from a mouse immunized with nontypeable Haemophilus influenzae produced a monoclonal antibody (MAb), designated 3B9, that bound to 35 of 35 H. ducreyi strains isolated from diverse geographic regions. The MAb 3B9 bound to a non-heat-modifiable H. ducreyi outer membrane protein (OMP) whose apparent molecular weight was 18,000 (the 18K OMP), and the 3B9 epitope did not phase vary at a rate of greater than 10(-3) in H. ducreyi. In immunoelectron microscopy, the 3B9 epitope was surface exposed, and there was intrastrain and interstrain variability in the amount of 3B9 labelling of whole cells. The MAb 3B9 cross-reacted with many species of the family Pasteurellaceae and bound to the 16.6K peptidoglycan-associated lipoprotein (P6 or PAL) of H. influenzae. Unlike P6, the 18K OMP did not copurify with peptidoglycan. In Western blots (immunoblots), five of seven serum samples obtained from patients with chancroid and four of five serum samples obtained from patients with other genital ulcer diseases at the time of presentation contained antibodies that bound to the 18K OMP. In a competition enzyme-linked immunosorbent assay, four of these serum samples inhibited the binding of 3B9 to H. ducreyi by more than 50%. We conclude that members of Pasteurellaceae expressed a conserved epitope on OMPs that sometimes had different physical characteristics. Patients with chancroid usually have antibodies to the 18K OMP and the 3B9 epitope that may have resulted from infection with H. ducreyi or previous exposure to other Haemophilus or Actinobacillus sp. strains.

  20. The Role of Cytomegalovirus, Haemophilus Influenzae and Epstein Barr Virus in Guillain Barre Syndrome

    Directory of Open Access Journals (Sweden)

    Shahriar Nafissi

    2013-06-01

    Full Text Available Guillain Barre Syndrome (GBS is an inflammatory, usually demyelinating, polyneuropathy; clinically characterized by acute onset of symmetric progressive muscle weakness with loss of myotatic reflexes. Thirty five patients with GBS, defined clinically according to the criteria of Asbury and Cornblath, were recruited from three hospital affiliated to Tehran University of Medical Sciences. Controls: As a control group 35 age and sex matched patients with other neurological diseases admitted to the same hospital at the same time, were included in our study. Serum samples were collected before treatment from each patient (within 4 weeks after the disease onset and controls, and stored frozen at -80ºC until serologic assays were done. Serologic testing of pretreatment serum was performed in all patients. Positive titer of virus specific IgM antibody against cytomegalovirus (CMV was found in 6 cases and 2 controls. 34 patients and 31 controls had high titer of anti Haemophilus influenzae IgG and one patient had serologic evidence of a recent Epstein Barr virus (EBV infection. The mean titer of IgG antibody against Haemophilus influenzae in cases and controls was 5.21 and 2.97 respectively. Although serologic evidence of all these infections were more frequent in cases than in controls, only Haemophilus influenzae infection appeared to be significantly related to GBS (P=0.002. Eleven cases and 3 controls had high titers of IgG antibody against Haemophilus influenzae type B (titer >8. There is significant association between high titer of IgG antibody against Haemophilus influenzae and GBS (P=0.017. Our results provide further evidence that Haemophilus influenzae and probably CMV, can be associated with GBS

  1. The role of cytomegalovirus, Haemophilus influenzae and Epstein Barr virus in Guillain Barre syndrome.

    Directory of Open Access Journals (Sweden)

    Shahriar Nafissi

    2013-06-01

    Full Text Available Guillain Barre Syndrome (GBS is an inflammatory, usually demyelinating, polyneuropathy; clinically characterized by acute onset of symmetric progressive muscle weakness with loss of myotatic reflexes. Thirty five patients with GBS, defined clinically according to the criteria of Asbury and Cornblath, were recruited from three hospital affiliated to Tehran University of Medical Sciences.As a control group 35 age and sex matched patients with other neurological diseases admitted to the same hospital at the same time, were included in our study. Serum samples were collected before treatment from each patient (within 4 weeks after the disease onset and controls, and stored frozen at -80ºC until serologic assays were done. Serologic testing of pretreatment serum was performed in all patients. Positive titer of virus specific IgM antibody against cytomegalovirus (CMV was found in 6 cases and 2 controls. 34 patients and 31 controls had high titer of anti Haemophilus influenzae IgG and one patient had serologic evidence of a recent Epstein Barr virus (EBV infection. The mean titer of IgG antibody against Haemophilus influenzae in cases and controls was 5.21 and 2.97 respectively. Although serologic evidence of all these infections were more frequent in cases than in controls, only Haemophilus influenzae infection appeared to be significantly related to GBS (P=0.002. Eleven cases and 3 controls had high titers of IgG antibody against Haemophilus influenzae type B (titer >8. There is significant association between high titer of IgG antibody against Haemophilus influenzae and GBS (P=0.017. Our results provide further evidence that Haemophilus influenzae and probably CMV, can be associated with GBS.

  2. The role of cytomegalovirus, Haemophilus influenzae and Epstein Barr virus in Guillain Barre syndrome.

    Science.gov (United States)

    Nafissi, Shahriar; Vahabi, Zahra; Sadeghi Ghahar, Maryam; Amirzargar, Ali Akbar; Naderi, Soheil

    2013-07-13

    Guillain Barre Syndrome (GBS) is an inflammatory, usually demyelinating, polyneuropathy; clinically characterized by acute onset of symmetric progressive muscle weakness with loss of myotatic reflexes. Thirty five patients with GBS, defined clinically according to the criteria of Asbury and Cornblath, were recruited from three hospital affiliated to Tehran University of Medical Sciences. As a control group 35 age and sex matched patients with other neurological diseases admitted to the same hospital at the same time, were included in our study. Serum samples were collected before treatment from each patient (within 4 weeks after the disease onset) and controls, and stored frozen at -80ºC until serologic assays were done. Serologic testing of pretreatment serum was performed in all patients. Positive titer of virus specific IgM antibody against cytomegalovirus (CMV) was found in 6 cases and 2 controls. 34 patients and 31 controls had high titer of anti Haemophilus influenzae IgG and one patient had serologic evidence of a recent Epstein Barr virus (EBV) infection. The mean titer of IgG antibody against Haemophilus influenzae in cases and controls was 5.21 and 2.97 respectively. Although serologic evidence of all these infections were more frequent in cases than in controls, only Haemophilus influenzae infection appeared to be significantly related to GBS (P=0.002). Eleven cases and 3 controls had high titers of IgG antibody against Haemophilus influenzae type B (titer >8). There is significant association between high titer of IgG antibody against Haemophilus influenzae and GBS (P=0.017). Our results provide further evidence that Haemophilus influenzae and probably CMV, can be associated with GBS.

  3. Delineation of the species Haemophilus influenzae by phenotype, multilocus sequence phylogeny, and detection of marker genes

    DEFF Research Database (Denmark)

    Nørskov-Lauritsen, Niels; Overballe, MD; Kilian, Mogens

    2009-01-01

    branching cluster, intermingled with strains of "H. intermedius" and cryptic genospecies biotype IV. Although H. influenzae is phenotypically more homogenous than some other Haemophilus species, the genetic diversity and multicluster structure of strains traditionally associated with H. influenzae make...... genospecies biotype IV, and the never formally validated species "Haemophilus intermedius". Multilocus sequence phylogeny based on six housekeeping genes separated a cluster encompassing the type and the reference strains of H. influenzae from 31 more distantly related strains. Comparison of 16S rRNA gene...

  4. Identification of a siderophore utilization locus in nontypeable Haemophilus influenzae

    Directory of Open Access Journals (Sweden)

    Seale Thomas W

    2010-04-01

    Full Text Available Abstract Background Haemophilus influenzae has an absolute aerobic growth requirement for either heme, or iron in the presence of protoporphyrin IX. Both iron and heme in the mammalian host are strictly limited in their availability to invading microorganisms. Many bacterial species overcome iron limitation in their environment by the synthesis and secretion of small iron binding molecules termed siderophores, which bind iron and deliver it into the bacterial cell via specific siderophore receptor proteins on the bacterial cell surface. There are currently no reports of siderophore production or utilization by H. influenzae. Results Comparative genomics revealed a putative four gene operon in the recently sequenced nontypeable H. influenzae strain R2846 that encodes predicted proteins exhibiting significant identity at the amino acid level to proteins involved in the utilization of the siderophore ferrichrome in other bacterial species. No siderophore biosynthesis genes were identified in the R2846 genome. Both comparative genomics and a PCR based analysis identified several additional H. influenzae strains possessing this operon. In growth curve assays strains containing the genes were able to utilize ferrichrome as an iron source. H. influenzae strains lacking the operon were unable to obtain iron from ferrichrome. An insertional mutation in one gene of the operon abrogated the ability of strains to utilize ferrichrome. In addition transcription of genes in the identified operon were repressible by high iron/heme levels in the growth media. Conclusions We have identified an iron/heme-repressible siderophore utilization locus present in several nontypeable H. influenzae strains. The same strains do not possess genes encoding proteins associated with siderophore synthesis. The siderophore utilization locus may enable the utilization of siderophores produced by other microorganisms in the polymicrobial environmental niche of the human nasopharynx

  5. Metabolic versatility in Haemophilus influenzae: a metabolomic and genomic analysis.

    Science.gov (United States)

    Othman, Dk Seti Maimonah Pg; Schirra, Horst; McEwan, Alastair G; Kappler, Ulrike

    2014-01-01

    Haemophilus influenzae is a host adapted human pathogen known to contribute to a variety of acute and chronic diseases of the upper and lower respiratory tract as well as the middle ear. At the sites of infection as well as during growth as a commensal the environmental conditions encountered by H. influenzae will vary significantly, especially in terms of oxygen availability, however, the mechanisms by which the bacteria can adapt their metabolism to cope with such changes have not been studied in detail. Using targeted metabolomics the spectrum of metabolites produced during growth of H. influenzae on glucose in RPMI-based medium was found to change from acetate as the main product during aerobic growth to formate as the major product during anaerobic growth. This change in end-product is likely caused by a switch in the major route of pyruvate degradation. Neither lactate nor succinate or fumarate were major products of H. influenzae growth under any condition studied. Gene expression studies and enzyme activity data revealed that despite an identical genetic makeup and very similar metabolite production profiles, H. influenzae strain Rd appeared to favor glucose degradation via the pentose phosphate pathway, while strain 2019, a clinical isolate, showed higher expression of enzymes involved in glycolysis. Components of the respiratory chain were most highly expressed during microaerophilic and anaerobic growth in both strains, but again clear differences existed in the expression of genes associated e.g., with NADH oxidation, nitrate and nitrite reduction in the two strains studied. Together our results indicate that H. influenzae uses a specialized type of metabolism that could be termed "respiration assisted fermentation" where the respiratory chain likely serves to alleviate redox imbalances caused by incomplete glucose oxidation, and at the same time provides a means of converting a variety of compounds including nitrite and nitrate that arise as part of

  6. Metabolic versatility in Haemophilus influenzae: a metabolomic and genomic analysis

    Directory of Open Access Journals (Sweden)

    Dk Seti Maimonah Pg eOthman

    2014-03-01

    Full Text Available Haemophilus influenzae is a host adapted human pathogen known to contribute to a variety of acute and chronic diseases of the upper and lower respiratory tract as well as the middle ear. At the sites of infection as well as during growth as a commensal the environmental conditions encountered by H. influenzae will vary significantly, especially in terms of oxygen availability, however, the mechanisms by which the bacteria can adapt their metabolism to cope with such changes have not been studied in detail. Using targeted metabolomics the spectrum of metabolites produced during growth of H. influenzae on glucose in RPMI-based medium was found to change from acetate as the main product during aerobic growth to formate as the major product during anaerobic growth. This is likely caused by a switch in the major pyruvate degrading route. Neither lactate nor succinate or fumarate were major products of H. influenzae growth under any condition studied Gene expression studies and enzyme activity data revealed that despite an identical genetic makeup and very similar metabolite production profiles, H. influenzae strain Rd appeared to favour glucose degradation via the PPP, while strain 2019, a clinical isolate, showed higher expression of enzymes involved in glycolysis. Components of the respiratory chain were most highly expressed during microaerophilic and anaerobic growth in both strains, but again clear differences existed in the expression of genes associated e.g. with NADH oxidation, nitrate and nitrite reduction in the two strains studied.Together our results indicate that H. influenzae uses a specialized type of metabolism that could be termed ‘respiration assisted fermentation’ where the respiratory chain likely serves to alleviate redox imbalances caused by incomplete glucose oxidation, and at the same time provides a means of converting a variety of compounds including nitrite and nitrate that arise as part of the host defence mechanisms.

  7. Beta- lactam antibiotics stimulate biofilm formation in non-typeable haemophilus influenzae by up-regulating carbohydrate metabolism.

    Directory of Open Access Journals (Sweden)

    Siva Wu

    Full Text Available Non-typeable Haemophilus influenzae (NTHi is a common acute otitis media pathogen, with an incidence that is increased by previous antibiotic treatment. NTHi is also an emerging causative agent of other chronic infections in humans, some linked to morbidity, and all of which impose substantial treatment costs. In this study we explore the possibility that antibiotic exposure may stimulate biofilm formation by NTHi bacteria. We discovered that sub-inhibitory concentrations of beta-lactam antibiotic (i.e., amounts that partially inhibit bacterial growth stimulated the biofilm-forming ability of NTHi strains, an effect that was strain and antibiotic dependent. When exposed to sub-inhibitory concentrations of beta-lactam antibiotics NTHi strains produced tightly packed biofilms with decreased numbers of culturable bacteria but increased biomass. The ratio of protein per unit weight of biofilm decreased as a result of antibiotic exposure. Antibiotic-stimulated biofilms had altered ultrastructure, and genes involved in glycogen production and transporter function were up regulated in response to antibiotic exposure. Down-regulated genes were linked to multiple metabolic processes but not those involved in stress response. Antibiotic-stimulated biofilm bacteria were more resistant to a lethal dose (10 µg/mL of cefuroxime. Our results suggest that beta-lactam antibiotic exposure may act as a signaling molecule that promotes transformation into the biofilm phenotype. Loss of viable bacteria, increase in biofilm biomass and decreased protein production coupled with a concomitant up-regulation of genes involved with glycogen production might result in a biofilm of sessile, metabolically inactive bacteria sustained by stored glycogen. These biofilms may protect surviving bacteria from subsequent antibiotic challenges, and act as a reservoir of viable bacteria once antibiotic exposure has ended.

  8. Beta- Lactam Antibiotics Stimulate Biofilm Formation in Non-Typeable Haemophilus influenzae by Up-Regulating Carbohydrate Metabolism

    Science.gov (United States)

    Wu, Siva; Li, Xiaojin; Gunawardana, Manjula; Maguire, Kathleen; Guerrero-Given, Debbie; Schaudinn, Christoph; Wang, Charles; Baum, Marc M.; Webster, Paul

    2014-01-01

    Non-typeable Haemophilus influenzae (NTHi) is a common acute otitis media pathogen, with an incidence that is increased by previous antibiotic treatment. NTHi is also an emerging causative agent of other chronic infections in humans, some linked to morbidity, and all of which impose substantial treatment costs. In this study we explore the possibility that antibiotic exposure may stimulate biofilm formation by NTHi bacteria. We discovered that sub-inhibitory concentrations of beta-lactam antibiotic (i.e., amounts that partially inhibit bacterial growth) stimulated the biofilm-forming ability of NTHi strains, an effect that was strain and antibiotic dependent. When exposed to sub-inhibitory concentrations of beta-lactam antibiotics NTHi strains produced tightly packed biofilms with decreased numbers of culturable bacteria but increased biomass. The ratio of protein per unit weight of biofilm decreased as a result of antibiotic exposure. Antibiotic-stimulated biofilms had altered ultrastructure, and genes involved in glycogen production and transporter function were up regulated in response to antibiotic exposure. Down-regulated genes were linked to multiple metabolic processes but not those involved in stress response. Antibiotic-stimulated biofilm bacteria were more resistant to a lethal dose (10 µg/mL) of cefuroxime. Our results suggest that beta-lactam antibiotic exposure may act as a signaling molecule that promotes transformation into the biofilm phenotype. Loss of viable bacteria, increase in biofilm biomass and decreased protein production coupled with a concomitant up-regulation of genes involved with glycogen production might result in a biofilm of sessile, metabolically inactive bacteria sustained by stored glycogen. These biofilms may protect surviving bacteria from subsequent antibiotic challenges, and act as a reservoir of viable bacteria once antibiotic exposure has ended. PMID:25007395

  9. Oropharyngeal colonization by Haemophilus influenzae in healthy children from Taubaté (São Paulo), prior to the Haemophilus influenzae type b vaccination program in Brazil

    OpenAIRE

    Lucia Ferro Bricks; Caio Márcio Figueredo Mendes; Bianca Rezende Lucarevschi; Carmem Paz Oplustil; Zanella, Rosemeire C.; Adriana Bori; Ciro João Bertoli

    2004-01-01

    Haemophilus influenzae is one of the most important bacterial agents of otitis and sinusitis. H. influenzae type b (Hib) is one of the main causes of meningitis, pneumonia, and septicemia in nonvaccinated children under 6 years of age. The aims of this study were to determine the prevalence of H. influenzae and Hib oropharyngeal colonization prior to the onset of the Hib vaccination program in Brazil in previously healthy children and to assess the susceptibility profile of this microorganism...

  10. Low occurrence of 'non-haemolytic Haemophilus haemolyticus' misidentified as Haemophilus influenzae in cystic fibrosis respiratory specimens, and frequent recurrence of persistent H. influenzae clones despite antimicrobial treatment.

    Science.gov (United States)

    Fenger, Mette G; Ridderberg, Winnie; Olesen, Hanne V; Nørskov-Lauritsen, Niels

    2012-12-01

    Non-influenzae commensal Haemophilus species of low pathogenicity may be difficult to discriminate from Haemophilus influenzae. We investigated the level of misidentifications in respiratory specimens from cystic fibrosis patients and evaluated the colonisation dynamics of genuine H. influenzae isolates. One hundred and ninety-two presumptive H. influenzae isolates were re-examined by assessment of marker genes sodC and fucK, and isolates with aberrant genotypes were subjected to multilocus sequence typing. Misidentifications (3%) were mainly caused by failure to identify porphyrin-synthesising strains, and only a single strain (0.5%) could be classified as 'non-haemolytic Haemophilus haemolyticus'. Sequential isolates of confirmed H. influenzae isolates from individual patients were typed by pulsed-field gel electrophoresis. Despite the routine prescription of antimicrobial therapy, the majority of H. influenzae isolates were identical with at least one of the strains cultured from the two preceding positive samples from the same patient. Copyright © 2012 Elsevier GmbH. All rights reserved.

  11. Antibody response to Haemophilus influenzae type b capsular polysaccharide conjugated to tetanus toxoid in preterm infants

    DEFF Research Database (Denmark)

    Kristensen, Kim; Gyhrs, A; Lausen, B

    1996-01-01

    OBJECTIVE: To evaluate the antibody response to a Haemophilus influenzae type b capsular polysaccharide (HibCP) tetanus toxoid (TT) conjugate vaccine (HibCP-TT) in preterm infants. SUBJECTS: Thirty-five healthy preterm infants with gestational ages (GA) from 27 to 36 weeks and birth weights from...

  12. Immunological characterization of conjugated Haemophilus influenzae type b vaccine failure in infants

    NARCIS (Netherlands)

    Breukels, M. A.; Spanjaard, L.; Sanders, L. A.; Rijkers, G. T.

    2001-01-01

    Infant vaccination with conjugated Haemophilus influenzae type b (Hib) vaccine is highly effective in protecting against invasive Hib infections, but vaccine failures do occur. Twenty-one vaccine failures are reported since the introduction of the Hib conjugate vaccine in The Netherlands. Of the 14

  13. Bacterial Lysis through Interference with Peptidoglycan Synthesis Increases Biofilm Formation by Nontypeable Haemophilus influenzae

    NARCIS (Netherlands)

    Marti, S.; Puig, C.; Merlos, A.; Vinas, M.; Jonge, M.I. de; Linares, J.; Ardanuy, C.; Langereis, J.D.

    2017-01-01

    Nontypeable Haemophilus influenzae (NTHi) is an opportunistic pathogen that mainly causes otitis media in children and community-acquired pneumonia or exacerbations of chronic obstructive pulmonary disease in adults. A large variety of studies suggest that biofilm formation by NTHi may be an

  14. Recurrent Posttraumatic Meningitis due to Nontypable Haemophilus influenzae: Case Report and Review of the Literature

    DEFF Research Database (Denmark)

    Kunze, W; Müller, L; Kilian, Mogens

    2007-01-01

    We report a case of relapsing Haemophilus influenzae meningitis in a boy at the age of nearly 3 years and 4.2 years who had been successfully vaccinated against H. influenzae serotype b (Hib). The pathogen was a nonencapsulated (nontypable) H. influenzae strain of biotypes III and VI, respectively...

  15. Draft genome sequences for ten isolates of the swine respiratory pathogen Haemophilus Parasuis

    Science.gov (United States)

    Haemophilus parasuis is a swine pathogen that causes pneumonia and Glässer’s disease, a systemic syndrome of polyserositis, arthritis, and meningitis. We report here the draft genomes of ten geographically diverse isolates collectively representing the full virulence spectrum of H. parasuis. These...

  16. Epidemiology of Haemophilus influenzae bacteremia: A multi-national population-based assessment

    DEFF Research Database (Denmark)

    Laupland, Kevin B; Schønheyder, Henrik C; Østergaard, Christian

    2011-01-01

    independently associated with death at 30-days in logistic regression analysis included male gender, hospital-onset disease, older age, and lower respiratory tract, central nervous system, or unknown focus of infection. CONCLUSIONS: Haemophilus influenzae is an important cause of morbidity and mortality...

  17. Blocking of fimbria-mediated adherence of Haemophilus influenzae by sialyl gangliosides

    NARCIS (Netherlands)

    van Alphen, L.; Geelen-van den Broek, L.; Blaas, L.; van Ham, M.; Dankert, J.

    1991-01-01

    The structure of the receptor for the fimbriae of Haemophilus influenzae on human oropharyngeal epithelial cells and erythrocytes was determined in inhibition experiments with various sugars, glycolipids, and glycoproteins. Of 30 monosaccharides and disaccharides at a concentration of 0.1 M and of 3

  18. Toename van het aantal invasieve infecties door Haemophilus influenzae type b

    NARCIS (Netherlands)

    Spanjaard, L.; van den Hof, S.; de Melker, H. E.; Vermeer-de Bondt, P. E.; van der Ende, A.; Rijkers, G. T.

    2005-01-01

    OBJECTIVE: To describe the increase of invasive Haemophilus influenzae type b (Hib) infections in The Netherlands before and after the introduction of Hib vaccination in 1993, and to hypothesise about possible explanations. DESIGN: Descriptive. METHOD: Data on the prevalence of invasive Hib

  19. Haemophilus influenzae Type b Invasive Disease in Amish Children, Missouri, USA, 2014.

    Science.gov (United States)

    Myers, Angela L; Jackson, Mary Anne; Zhang, Lixin; Swanson, Douglas S; Gilsdorf, Janet R

    2017-01-01

    During 5 months in 2014, three Amish children in Missouri, USA, were diagnosed with invasive Haemophilus influenzae type b infection. Two were rural neighbors infected with a genetically similar rare strain, sequence type 45. One child had recently traveled, raising the possibility of maintenance of this strain among unvaccinated carriers in Amish communities.

  20. Factors affecting isolation and identification of Haemophilus vaginalis (Corynebacterium vaginale).

    Science.gov (United States)

    Bailey, R K; Voss, J L; Smith, R F

    1979-01-01

    The rate of isolation of organisms resembling Haemophilus vaginalis (Corynebacterium vaginale) from vaginal specimens was not significantly affected by anaerobic versus carbon dioxide incubation atmospheres or whether specimens were inoculated on isolation media immediately after collection or after a delay of 6 h. Forty-one clinically isolated strains were provisionally divided into 30 H. vaginalis strains and 11 H. vaginalis-like (HVL) strains based on morphological and growth characteristics. The H. vaginalis strains were less reactive in API-20A identification test strips, (Analytab Products, Inc.) using Lombard-Dowell broth, than in a modified basal medium that contained proteose peptone no. 3 (Difco). The numbers and kinds of substrates fermented by 30 clinical and 2 reference strains of H. vaginalis varied among conventional, API, Minitek (Baltimore Biological Laboratory), and rapid buffered substrate fermentation systems. A greater number and variety of carbohydrates were fermented by the 11 HVL strains more consistently in all four test systems. Analysis of volatile and nonvolatile fermentation end products by gas-liquid chromatography did not reveal significant differences between the H. vaginalis and HVL strains. However, the latter group grew in peptone-yeast extract-glucose broth, whereas the H. vaginalis strains did not grow without the addition of starch to peptone-yeast extract-glucose. All of the reference and clinical strains were similar in their susceptibilities to a variety of antimicrobial compounds except sulfonamides, which inhibited the HVL strains and bifidobacteria but not the H. vaginalis strains. Sulfonamide susceptibility or resistance corresponded in part to the H. vaginalis and HVL-bifidobacteria strain reactions on selected conventional fermentation substrates. Susceptibility or resistance to sulfonamides and metronidazole in conjunction with fermentation tests is described to aid in the separation of H. vaginalis from other

  1. Haemophilus pittmaniae respiratory infection in a patient with siderosis: a case report

    Directory of Open Access Journals (Sweden)

    Boucher Mathilde

    2012-04-01

    Full Text Available Abstract Introduction Haemophilus pittmaniae was described in 2005 as a new species distantly related to Haemophilus parainfluenzae. This member of the human saliva microbiota has also been further isolated from various body fluids without formal description of the patients. Case presentation We report the case of H. pittmaniae isolate made from a sputum specimen collected from a 58-year-old Caucasian man with a massive fibrotic form of siderosis who was awaiting lung transplantation. Identification of the isolate was ascertained by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and 16S rRNA gene sequencing. H. pittmaniae was considered to be responsible for the worsening of the patient’s chronic respiratory failure and was successfully treated with oral amoxicillin. Conclusion H. pittmaniae should be regarded as a new pathogen responsible for respiratory tract infection in patients with chronic lung diseases.

  2. [Diagnostics of invasive meningococcal, haemophilus and pneumococcal disease by PCR assay].

    Science.gov (United States)

    Kalmusová, Jitka; Bronská, Eva; Krízová, Pavla

    2004-06-01

    Development of extended polymerase chain reaction (PCR) for non-culture detection of Nesseria meningitidis, Haemophilus influenzae and Streptococcus pneumonie from invasive infections. A method of PCR was optimalised on strains of Nesseria meningitidis, Haemophilus influenzae b and Streptococcus pneumonie. Detection of pathogens was evaluated on 230 samples from patiens with invasive infection. Positive results of PCR were found in 103 samples of 230 (44.7 %). The percentage of positivity was higher in CSF samples (57.0 %) than in serum (33.8 %) or blood (33.3 %) samples. PCR method enables etiological diagnostics in cases, where antibiotic treatment was started. PCR results are available earlier than the results of cultivation. Multilocus sequence typing (MLST) of PCR products enables clonal analysis of etiological agents even in cases with negative results of cultivation.

  3. Structural requirements of the major protective antibody to Haemophilus influenzae type b

    DEFF Research Database (Denmark)

    Hougs, L; Juul, L; Svejgaard, A

    1999-01-01

    Protective antibodies to the important childhood pathogen Haemophilus influenzae type b (Hib) are directed against the capsular polysaccharide (HibCP). Most of the antibody is encoded by a well-defined set of ("canonical") immunoglobulin genes, including the Vkappa A2 gene, and expresses an idiot......Protective antibodies to the important childhood pathogen Haemophilus influenzae type b (Hib) are directed against the capsular polysaccharide (HibCP). Most of the antibody is encoded by a well-defined set of ("canonical") immunoglobulin genes, including the Vkappa A2 gene, and expresses...... an idiotypic marker (HibId-1). In comparison to noncanonical antibodies, the canonical antibody is generally of higher avidity, shows higher levels of in vitro bactericidal activity, and is more protective in infant rats. Using site-directed mutagenesis, we here characterize canonical HibCP antibodies...

  4. The Role of α-Defensins 1–3 in Antimicrobial Protection Forming in Children with Recurrent Bronchitis Caused by Bacteria of the Genus Haemophilus

    Directory of Open Access Journals (Sweden)

    G.O. Lezhenko

    2013-03-01

    Full Text Available The level of α-defensins 1–3 (HNP 1–3 has been analyzed in the blood plasma of children with recurrent bronchitis caused by bacteria of the genus Haemophilus. It is shown that the level of HNP 1–3 in the blood plasma depends on the form of Haemophilus. Trigger of HNP 1–3 outflow for neutrophils was the presence of bacterial capsule while presence of L-forms of Haemophilus influenzae wasn’t associated with increase in synthesis of antimicrobial peptides that could be one of the factors of forming of Haemophilus antibiotic resistance.

  5. Molecular Cloning, Expression and Purification of Truncated hpd Fragment of Haemophilus influenzae in Escherichia coli

    OpenAIRE

    Behrouzi, Ava; Bouzari, Saeid; Siadat, Seyed Davar; Jafari, Anis; Irani, Shiva

    2015-01-01

    Background: Nontypeable Haemophilus influenzae (NTHi) is a significant pathogen in children, causing otitis media, sinusitis, conjunctivitis, pneumonia, and occasionally invasive infections. Protein D (PD) belongs to the minor outer-membrane proteins of H. influenza. Moreover, it has been shown that this protein is one of the most potent vaccine candidates against the NTHi strain. Objectives: In the present study, a new truncated form of PD was designed based on conserved areas, and recombina...

  6. Vaccination of gnotobiotic primary specific pathogen-free pigs against Haemophilus parasuis.

    OpenAIRE

    Miniats, O P; Smart, N L; Ewert, E

    1991-01-01

    Three trials were conducted to establish if young primary specific pathogen free (SPF) pigs could be protected from Glasser's disease by vaccination. Three age groups of cesarean-derived isolator-reared gnotobiotic pigs were vaccinated twice at 4 and 6, 3 and 5, and 2 and 4 wk of age respectively with a formalin killed aluminum hydroxide adsorbed bacterin prepared from three strains of Haemophilus parasuis isolated from Ontario pigs affected with Glasser's disease. When challenged two weeks l...

  7. Genome-Wide Association Studies of Virulent and Avirulent Haemophilus parasuis Serotype 4 Strains

    OpenAIRE

    Lawrence, Paulraj K.; Wiener, Brittanny L.; Kolander-Bremer, Tammy; Bey, Russell F.; Stine, Douglas L.; Kittichotirat, Weerayuth; Bumgarner, Roger E.

    2014-01-01

    Haemophilus parasuis is a normal commensal of the upper respiratory tract of healthy pigs. However, in conjunction with stress and/or viral infections, or in immunocompromised animals, H. parasuis can transform into a pathogen causing Glasser’s disease, which is typically characterized by fibrinous polyserositis, polyarthritis, meningitis, and sometimes acute pneumonia and septicemia. H. parasuis serotype 5 is highly virulent and more frequently isolated from respiratory and systemic infectio...

  8. Limited Interactions between Streptococcus Suis and Haemophilus Parasuis in In Vitro Co-Infection Studies

    OpenAIRE

    Annabelle Mathieu-Denoncourt; Corinne Letendre; Jean-Philippe Auger; Mariela Segura; Virginia Aragon; Sonia Lacouture; Marcelo Gottschalk

    2018-01-01

    Streptococcus suis and Haemophilus parasuis are normal inhabitants of the porcine upper respiratory tract but are also among the most frequent causes of disease in weaned piglets worldwide, causing inflammatory diseases such as septicemia, meningitis and pneumonia. Using an in vitro model of infection with tracheal epithelial cells or primary alveolar macrophages (PAMs), it was possible to determine the interaction between S. suis serotype 2 and H. parasuis strains with different level of vir...

  9. Development of PCR assays to detect ampicillin resistance genes in cerebrospinal fluid samples containing Haemophilus influenzae.

    OpenAIRE

    Tenover, F C; Huang, M B; Rasheed, J K; Persing, D H

    1994-01-01

    We developed PCR primers specific for the blaTEM and blaROB ampicillin resistance genes. The specificity of the primers was confirmed by testing a series of Escherichia coli isolates containing a variety of ampicillin resistance genes and a series of ampicillin-resistant and ampicillin-susceptible Haemophilus influenzae isolates. There was a perfect correlation between ampicillin MICs, the presence of beta-lactamase (as determined by the nitrocefin test), and the results with the blaTEM and b...

  10. Comparative transcriptional profiling of tildipirosin-resistant and sensitive Haemophilus parasuis

    OpenAIRE

    Lei, Zhixin; Fu, Shulin; Yang, Bing; Liu, Qianying; Ahmed, Saeed; Xu, Lei; Xiong, Jincheng; Cao, Jiyue; Qiu, Yinsheng

    2017-01-01

    Numerous studies have been conducted to examine the molecular mechanism of Haemophilus parasuis resistance to antibiotic, but rarely to tildipirosin. In the current study, transcriptional profiling was applied to analyse the variation in gene expression of JS0135 and tildipirosin-resistant JS32. The growth curves showed that JS32 had a higher growth rate but fewer bacteria than JS0135. The cell membranes of JS32 and a resistant clinical isolate (HB32) were observed to be smoother than those o...

  11. Blocking of fimbria-mediated adherence of Haemophilus influenzae by sialyl gangliosides.

    OpenAIRE

    van Alphen, L; Geelen-van den Broek, L; Blaas, L; van Ham, M; Dankert, J

    1991-01-01

    The structure of the receptor for the fimbriae of Haemophilus influenzae on human oropharyngeal epithelial cells and erythrocytes was determined in inhibition experiments with various sugars, glycolipids, and glycoproteins. Of 30 monosaccharides and disaccharides at a concentration of 0.1 M and of 3 polysaccharides at a concentration of 1 mg/ml, none inhibited fimbria-specific adherence and hemagglutination. Inhibition was obtained with gangliosides GM1, GM2, GM3, and GD1a in nanomolar concen...

  12. Haemophilus parainfluenzae Endocarditis Associated With Maxillary Sinusitis and Complicated by Cerebral Emboli in a Young Man.

    Science.gov (United States)

    Duzenli, Anthony E; Dwyer, John; Carey, Jeanne

    2017-01-01

    HACEK endocarditis is often difficult to diagnose given the slow-growing characteristics of the organisms involved. Haemophilus parainfluenzae, one of the HACEK organisms, is an uncommon cause of endocarditis. We describe a case of a previously healthy young man with H parainfluenzae endocarditis that was associated with maxillary sinusitis and severe systemic complications, including septic cerebral emboli and mitral valve perforation. Previously reported cases have also described a predilection for younger people, cardiac valve pathology, and a high prevalence of stroke.

  13. Invasive Haemophilus Influenzae Disease, Europe, 1996–2006

    Centers for Disease Control (CDC) Podcasts

    2010-03-15

    This podcast describes monitoring of Haemophilus influenzae disease in Europe from 1996 through 2006. CDC epidemiologist Stacey Martin discusses what researchers learned about the effect of vaccination on disease prevalence.  Created: 3/15/2010 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID); National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 4/5/2010.

  14. Culture of non-typeable Haemophilus influenzae from the nasopharynx: Not all media are equal.

    Science.gov (United States)

    Harris, Tegan M; Rumaseb, Angela; Beissbarth, Jemima; Barzi, Federica; Leach, Amanda J; Smith-Vaughan, Heidi C

    2017-06-01

    The efficacy of chocolate agar, versus bacitracin, vancomycin, clindamycin, chocolate agar (BVCCA) for the isolation of non-typeable Haemophilus influenzae (NTHi) from nasopharyngeal swabs was determined. BVCCA cultured NTHi from 97.3% of NTHi-positive swabs, compared to 87.1% for chocolate agar. To maximise culture sensitivity, the use of both media is recommended. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Lower airway colonization and inflammatory response in COPD: a focus on Haemophilus influenzae

    Directory of Open Access Journals (Sweden)

    Finney LJ

    2014-10-01

    Full Text Available Lydia J Finney,1 Andrew Ritchie,1 Elizabeth Pollard,2 Sebastian L Johnston,1 Patrick Mallia1 1Airway Disease Infection Section, National Heart and Lung Institute, Imperial College, London, United Kingdom; 2King's College London, London, United Kingdom Abstract: Bacterial infection of the lower respiratory tract in chronic obstructive pulmonary disease (COPD patients is common both in stable patients and during acute exacerbations. The most frequent bacteria detected in COPD patients is Haemophilus influenzae, and it appears this organism is uniquely adapted to exploit immune deficiencies associated with COPD and to establish persistent infection in the lower respiratory tract. The presence of bacteria in the lower respiratory tract in stable COPD is termed colonization; however, there is increasing evidence that this is not an innocuous phenomenon but is associated with airway inflammation, increased symptoms, and increased risk for exacerbations. In this review, we discuss host immunity that offers protection against H. influenzae and how disturbance of these mechanisms, combined with pathogen mechanisms of immune evasion, promote persistence of H. influenzae in the lower airways in COPD. In addition, we examine the role of H. influenzae in COPD exacerbations, as well as interactions between H. influenzae and respiratory virus infections, and review the role of treatments and their effect on COPD outcomes. This review focuses predominantly on data derived from human studies but will refer to animal studies where they contribute to understanding the disease in humans. Keywords: chronic obstructive pulmonary disease, Haemophilus influenzae, nontypeable Haemophilus influenzae, respiratory viruses, vaccination

  16. Virtual screening of phytochemicals to novel targets in Haemophilus ducreyi towards the treatment of Chancroid.

    Science.gov (United States)

    Tripathi, Pranav; Chaudhary, Ritu; Singh, Ajeet

    2014-01-01

    Conventionally, drugs are discovered by testing chemically synthesized compounds against a battery of in vivo biological screens. Information technology and Omic science enabled us for high throughput screening of compound libraries against biological targets and hits are then tested for efficacy in cells or animals. Chancroid, caused by Haemophilus ducreyi is a public health problem and has been recognized as a cofactor for Human Immunodeficiency Virus (HIV) transmission. It facilitates HIV transmission by providing an accessible portal entry, promoting viral shedding, and recruiting macrophages as well as CD4 cells to the skin. So, there is a requirement to develop an efficient drug to combat Chancroid that can also diminish HIV infection. In-silico screening of potential inhibitors against the target may facilitate in detection of the novel lead compounds for developing an effective chemo preventive strategy against Haemophilus ducreyi. The present study has investigated the effects of approximately 1100 natural compounds that inhibit three vital enzymes viz. Phosphoenolpyruvate phosphotransferase, Acetyl-coenzyme A carboxylase and Fructose 1, 6-bisphosphatase of Haemophilus ducreyi in reference to a commercial drug Rifabutin. Results reveal that the lead compound uses less energy to bind to target. The lead compound parillin has also been predicted as less immunogenic in comparison to Rifabutin. Further, better molecular dynamics, pharmacokinetics, pharmacodynamics and ADME-T properties establish it as an efficient chancroid preventer.

  17. Fallos vacunales a vacunas conjugadas de Streptococcus pneumoniae y Haemophilus influenzae tipo b

    Directory of Open Access Journals (Sweden)

    Gonzalo Angulo

    2016-11-01

    Full Text Available Haemophilus influenzae type b and Streptococcus pneumoniae are the main cause agents of otitis, pneumonia, sepsis and meningitis, affecting mainly children under 5 years. Conjugate vaccines for encapsulated germs have dramatically decreased, the various diseases caused by these germs. Despite the decrease in morbidity and mortality, vaccine failures were observed. Children who experienced vaccine failures to Haemophilus influenzae type b had associated comorbidities more frequently than the general population (prematurity, HIV, Down syndrome, tumors, etc.. Nevertheless, most of these children have no medical history or immunological disorders. There is no consensus on whether all patients with vaccine failures should be assessed immunologically and how. There are recommendations to indicate a booster dose to patients with certain comorbidities and patients experiencing vaccine failure even in the absence of theses. Of the vaccine preparations available for Haemophilus influenzae type b association with acellular Bordetella pertussis proved to be less immunogenic and is currently being discouraged. Streptococcus pneumoniae serotypes 6B and 19F are less immunogenics and explain most of the vaccine failures in some series.

  18. Haemophilus parainfluenzae Mural Endocarditis: Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Luca T. Giurgea

    2016-01-01

    Full Text Available Haemophilus parainfluenzae, which uncommonly causes endocarditis, has never been documented to cause mural involvement. A 62-year-old immunocompetent female without predisposing risk factors for endocarditis except for poor dentition presented with fever, emesis, and dysmetria. Echocardiography found a mass attached to the left ventricular wall with finger-like projections. Computed tomography showed evidence of embolic phenomena to the brain, kidneys, spleen, and colon. Cardiac MRI revealed involvement of the chordae tendineae of the anterior papillary muscles. Blood cultures grew Haemophilus parainfluenzae. The patient was treated successfully with ceftriaxone with resolution of symptoms, including neurologic deficits. After eleven days of antibiotics a worsening holosystolic murmur was discovered. Worsening mitral regurgitation on echocardiography was only found three weeks later. Nine weeks after presentation, intraoperative evaluation revealed chord rupture but no residual vegetation and mitral repair was performed. Four weeks after surgery, the patient was back to her baseline. This case illustrates the ability of Haemophilus parainfluenzae to form large mural vegetations with high propensity of embolization in otherwise normal cardiac tissue among patients with dental risk factors. It also underscores the importance of physical examination in establishing a diagnosis of endocarditis and monitoring for progression of disease.

  19. A glutathione-based system for defense against carbonyl stress in Haemophilus influenzae

    Directory of Open Access Journals (Sweden)

    Kidd Stephen P

    2012-07-01

    Full Text Available Abstract Background adhC from Haemophilus influenzae encodes a glutathione-dependent alcohol dehydrogenase that has previously been shown to be required for protection against killing by S-nitrosoglutathione (GSNO. This group of enzymes is known in other systems to be able to utilize substrates that form adducts with glutathione, such as aldehydes. Results Here, we show that expression of adhC is maximally induced under conditions of high oxygen tension as well as specifically with glucose as a carbon source. adhC could also be induced in response to formaldehyde but not GSNO. An adhC mutant was more susceptible than wild-type Haemophilus influenzae Rd KW20 to killing by various short chain aliphatic aldehydes, all of which can be generated endogenously during cell metabolism but are also produced by the host as part of the innate immune response. Conclusions These results indicate that AdhC plays a role in defense against endogenously generated reactive carbonyl electrophiles in Haemophilus influenzae and may also play a role in defense against the host innate immune system.

  20. Analysis of Hypoxemia in Early Ventilator-Associated Pneumonia Secondary to Haemophilus in Trauma Patients.

    Science.gov (United States)

    Ho, Vanessa P; Madbak, Firas; Horng, Helen; Sifri, Ziad C; Mohr, Alicia M

    2015-06-01

    Haemophilus species bacteria (HSB) are known pathogens responsible for early pneumonia in intubated trauma patients. The primary goal of this study was to examine the incidence and extent of hypoxemia in intubated trauma patients who develop early ventilator-associated pneumonia (VAP) secondary to HSB. On the basis of our clinical experiences, we hypothesized that patients with Haemophilus species bacteria pneumonia (HSBP) would have a high rate of hypoxemia but that the effect would be transient. Retrospective review of intubated trauma patients from an urban level I trauma center with HSBP diagnosed by deep tracheal aspirate or bronchoalveolar lavage from April 2007 to November 2012. Collected variables included day of HSBP diagnosis; PaO2 to FIO2 ratio (P:F) at HSBP diagnosis as well as HSBP day three and HSBP day seven; injury severity score (ISS) and its component parts; admission Glasgow Coma Scale (GCS) score; and mortality. Hypoxemia was defined as P:F hypoxemia were significantly less likely to have a severe head injury (GCShypoxemia had similar hospital length of stay and mortality to patients who did not develop hypoxemia. Haemophilus species bacteria pneumonia in trauma patients is associated with high rates of transient hypoxemia and a high tracheostomy rate, although subsequent outcomes are not affected. Patients with head injuries had a lower incidence of hypoxemia from pneumonia.

  1. Contribution of PBP3 Substitutions and TEM-1, TEM-15, and ROB-1 Beta-Lactamases to Cefotaxime Resistance in Haemophilus influenzae and Haemophilus parainfluenzae.

    Science.gov (United States)

    Søndergaard, Annette; Nørskov-Lauritsen, Niels

    2016-06-01

    To investigate the relative contributions of naturally occurring penicillin-binding protein 3 (PBP3) substitutions, and TEM-1, TEM-15, and ROB-1 beta-lactamases on resistance to a third-generation cephalosporin in Haemophilus influenzae and Haemophilus parainfluenzae. The minimum inhibitory concentration (MIC) of cefotaxime (CTX) was assessed after transformation with PCR-amplified ftsI genes expressing altered PBP3 and/or small plasmids encoding beta-lactamases into an isogenic environment of H. influenzae and H. parainfluenzae. Group III PBP3, comprising substitutions N526K, S385T, and L389F, conferred CTX resistance to H. influenzae according to EUCAST interpretative criteria. Group III-like PBP3, comprising substitutions N526H and S385T, increased the CTX MIC of H. parainfluenzae ninefold, but the level did not transgress the resistance breakpoint. Production of TEM-15 beta-lactamase conferred CTX resistance on both H. influenzae and H. parainfluenzae. A nitrocefin hydrolysis assay showed TEM-15 to be a less efficient enzyme compared to TEM-1. TEM-15 and PBP3 substitutions impose an additive effect on resistance to third-generation cephalosporins in both H. influenzae and H. parainfluenzae. The effect of PBP3 substitutions on beta-lactam resistance in H. parainfluenzae can be addressed by transfer of ftsI genes in vitro.

  2. Oropharyngeal colonization by Haemophilus influenzae in healthy children from Taubaté (São Paulo), prior to the Haemophilus influenzae type B vaccination program in Brazil.

    Science.gov (United States)

    Bricks, Lucia Ferro; Mendes, Caio Márcio Figueredo; Lucarevschi, Bianca Rezende; Oplustil, Carmem Paz; Zanella, Rosemeire C; Bori, Adriana; Bertoli, Ciro João

    2004-10-01

    Haemophilus influenzae is one of the most important bacterial agents of otitis and sinusitis. H. influenzae type b (Hib) is one of the main causes of meningitis, pneumonia, and septicemia in nonvaccinated children under 6 years of age. The aims of this study were to determine the prevalence of H. influenzae and Hib oropharyngeal colonization prior to the onset of the Hib vaccination program in Brazil in previously healthy children and to assess the susceptibility profile of this microorganism to a selected group of antimicrobials that are used to treat acute respiratory infections. Cultures of Haemophilus influenzae were made from oropharynx swabs from 987 children under 6 years of age who were enrolled in 29 day-care centers in Taubaté (a city of São Paulo state, Brazil) between July and December 1998. The prevalence of H. influenzae carriers was 17.4%, and only 5.5% of the strains were beta-lactamase producers. The prevalence of Hib carriers was high, 7.3% on average (range, 0.0 - 33.3%). The low prevalence of colonization by penicillin-resistant strains indicates that it is not necessary to substitute ampicilin or amoxicilin to effectively treat otitis and sinusitis caused by H. influenzae in Taubaté.

  3. The tympanic membrane and middle ear mucosa during non-typeable Haemophilus influenzae and Haemophilus influenzae type b acute otitis media: a study in the rat.

    Science.gov (United States)

    Magnuson, K; Hermansson, A; Melhus, A; Hellström, S

    1997-05-01

    Non-typeable Haemophilus influenzae (NTHi) and encapsulated Haemophilus influenzae type b (Hib) were inoculated into the middle ears of Sprague-Dawley rats. Tympanic membrane (TM) status was assessed otomicroscopically and specimens from various middle ear areas were prepared for light microscopy at various times during the acute phase and up to 6 months after inoculation. Irrespective of bacteria strain, acute otitis media (AOM) was present in all ears 4 days after inoculation. The Hib-infected ears showed initially a severe course of AOM, but all were otomicroscopically resolved by day 12, at which time a few NTHi-inoculated ears still exhibited middle ear effusion. The TMs infected with Hib had normalized without scar formation, whereas NTHi induced a persistent thickening of the TMs in half of all cases. The middle ear mucosa of NTHi-infected ears initially showed vigorous activity among the goblet cells, but the mucosa normalized after the acute phase. Hib, by contrast, induced prominent changes in the middle ear mucosa. Initially, no goblet cell granules or ciliated cells could be observed in the mucosa. Later on, the epithelium contained large, active goblet cells. Glands appeared beneath the mucosa which persisted as streaks of epithelial cells throughout the study period. The findings show that NTHi and Hib both induce AOM but with differing clinical courses, and affect different targets in the middle ear.

  4. The capsule biosynthesis locus of Haemophilus influenzae show conspicuous similarity to the corresponding locus in Haemophilus sputorum and may have been recruited from this species by horizontal gene transfer

    DEFF Research Database (Denmark)

    Nielsen, Signe Maria; de Gier, Camilla; Dimopoulou, Chrysoula

    2015-01-01

    The newly described species Haemophilus sputorum has been cultured from the upper respiratory tract of humans and appears to have little pathogenic potential. The species encode a capsular biosynthesis locus of approximately 12 kb composed of three distinct regions. Region I and III genes, involv...... from the commensal species H. sputorum by horizontal gene transfer.......The newly described species Haemophilus sputorum has been cultured from the upper respiratory tract of humans and appears to have little pathogenic potential. The species encode a capsular biosynthesis locus of approximately 12 kb composed of three distinct regions. Region I and III genes, involved...... in export and processing of the capsular material, show high similarity to the corresponding genes in capsulate lineages of the pathogenic species Haemophilus influenzae; indeed, standard bexA and bexB PCRs for detection of capsulated strains of H. influenzae give positive results with strains of H...

  5. Detection of Cryptic Genospecies Misidentified as Haemophilus influenzae in Routine Clinical Samples by Assessment of Marker Genes fucK, hap, and sodC▿

    Science.gov (United States)

    Nørskov-Lauritsen, Niels

    2009-01-01

    Clinical isolates of Haemophilus influenzae were assessed for the presence of fucK, hap, and sodC by hybridization with gene-specific probes, and isolates diverging from the expected H. influenzae genotype were characterized by phenotype and 16S rRNA gene sequencing. Two of 480 isolates were finally classified as variant strains (“nonhemolytic Haemophilus haemolyticus”). PMID:19535530

  6. Detection of cryptic genospecies misidentified as Haemophilus influenzae in routine clinical samples by assessment of marker genes fucK, hap, and sodC.

    Science.gov (United States)

    Nørskov-Lauritsen, Niels

    2009-08-01

    Clinical isolates of Haemophilus influenzae were assessed for the presence of fucK, hap, and sodC by hybridization with gene-specific probes, and isolates diverging from the expected H. influenzae genotype were characterized by phenotype and 16S rRNA gene sequencing. Two of 480 isolates were finally classified as variant strains ("nonhemolytic Haemophilus haemolyticus").

  7. Evolution of the paralogous hap and iga genes in Haemophilus influenzae: evidence for a conserved hap pseudogene associated with microcolony formation in the recently diverged Haemophilus aegyptius and H. influenzae biogroup aegyptius

    DEFF Research Database (Denmark)

    Kilian, Mogens; Poulsen, Knud; Lomholt, Hans Bredsted

    2002-01-01

    Certain non-capsulate strains belonging to the Haemophilus influenzae/Haemophilus aegyptius complex show unusually high pathogenicity, but the evolutionary origin of these virulent phenotypes, termed H. influenzae biogroup aegyptius, is as yet unknown. The aim of the present study was to elucidate...... as revealed by phylogenetic analysis. There was no evidence for a second, functional copy of the hap gene in these strains. The perturbed expression of the Hap serine protease appears to be associated with the formation of elongated bacterial cells growing in chains and a distinct colonization pattern...

  8. Aislamiento de distintos serotipos de Haemophilus influenzae en muestras profundas de pacientes pediátricos Isolation of Haemophilus influenzae serotypes from sterile sites in sick children

    Directory of Open Access Journals (Sweden)

    B.M. Gatti

    2004-03-01

    Full Text Available Haemophilus influenzae (Hi es responsable de diversas enfermedades humanas como sepsis, meningitis, celulitis y osteoartritis. En este trabajo se investigó la recuperación de distintos serotipos de Hi en muestras profundas de pacientes pediátricos. Se estudiaron 179 aislamientos de 146 niños durante el periodo 1996-2002 en el Laboratorio de Microbiología del Hospital de Niños Superiora Sor María Ludovica, Argentina. La distribución de los serotipos fue la siguiente: 1 a, 112 b, 1 c,1 d, 4 e, 3 f y 24 no tipificables. A partir del establecimiento de la estrategia de vacunación universal anti Hi b en 1998 se observa una disminución notable del serotipo b y un aumento relativo de otros y no tipificables.Haemophilus influenzae (Hi is the causative agent of several human diseases such as sepsis, meningitis, celulitis, and osteoarthritis. We investigated the isolation of Hi serotypes from sterile sites in sick children. One hundred and seventy nine strains from 146 patients were studied, period 1996-2002, at the Microbiology Laboratory, Hospital de Niños Superiora Sor María Ludovica, Argentina. The serotype distribution was:1 a, 112 b,1 c,1 d, 4 e, 3 f y 24 no typable. Since the beginning of universal Hi b vaccination in 1998, we have observed the fast decrease of serotype b and a relative increase of other serotypes.

  9. [Peritonitis in the course of peritoneal dialisis caused by Haemophilus influenzae with BLNAR phenotype].

    Science.gov (United States)

    Miklaszewska, Monika; Klepacka, Joanna; Drozdz, Dorota; Zachwieja, Katarzyna; Pietrzyk, Jacek A; Kadłubowski, Marcin; Hryniewicz, Waleria

    2009-04-01

    Most common bacterial species causing peritonitis in the course of peritoneal dialysis (PDP) are coagulase-negative staphylococci, Staphylococcus aureus and streptococci. Haemophilus influenzae is rarely associated with PDP. Hereby we present the first known case of APD-associated peritonitis caused by non-type able H. influenzae (NTHi) presenting the beta-lactamase negative, ampicillin-resistant (BLNAR) phenotype. An 18 year old boy who had been treated with the APD for 12 months due to SLE was admitted in good general condition with diagnosis of PDP. Standard diagnostic and therapeutical procedures were initiated. Dialysis fluid was turbid with cytosis of 435 WBC/ml. From dialysis fluid pure culture of Gram-negative coccobacillus was isolated. The isolate was identified as a BLNAR phenotype. The same bacterium was isolated from nasal swab. Blood cultures were negative. After evaluation of antimicrobial susceptibility the treatment was changed for the oral ciprofloxacin. The treatment was successful. Control tests 2 days later revealed cytosis of 15 WBC/mm3 and control cultures of peritoneal fluid were negative. After two weeks of treatment the patient was discharged in a good condition. Haemophilus influenzae is a bacterium frequently colonizing the nasopharyngeal cavity. A PCR-based method allowed to classify isolates as NTHi. Infection was probably of the respiratory origin as the isolates (from peritoneal fluid and nasal swab) were undistinguishable. There are only few reports describing this species as an ethiologic agent of peritonitis. This case prove that Haemophilus species should be taken into account as a possible aethiologic agent of PDP, especially in patients on immunosupression with carrier state of H. influenzae in the upper respiratory tract. This kind of microorganism requires specific conditions during its growing in vitro. Identification of its sensitivity to antibiotics is essential in order to detect strains of BLNAR phenotype, as it is a

  10. Molecular surveillance of true nontypeable Haemophilus influenzae: an evaluation of PCR screening assays.

    Science.gov (United States)

    Binks, Michael J; Temple, Beth; Kirkham, Lea-Ann; Wiertsema, Selma P; Dunne, Eileen M; Richmond, Peter C; Marsh, Robyn L; Leach, Amanda J; Smith-Vaughan, Heidi C

    2012-01-01

    Unambiguous identification of nontypeable Haemophilus influenzae (NTHi) is not possible by conventional microbiology. Molecular characterisation of phenotypically defined NTHi isolates suggests that up to 40% are Haemophilus haemolyticus (Hh); however, the genetic similarity of NTHi and Hh limits the power of simple molecular techniques such as PCR for species discrimination. Here we assess the ability of previously published and novel PCR-based assays to identify true NTHi. Sixty phenotypic NTHi isolates, classified by a dual 16S rRNA gene PCR algorithm as NTHi (n = 22), Hh (n = 27) or equivocal (n = 11), were further characterised by sequencing of the 16S rRNA and recA genes then interrogated by PCR-based assays targeting the omp P2, omp P6, lgtC, hpd, 16S rRNA, fucK and iga genes. The sequencing data and PCR results were used to define NTHi for this study. Two hpd real time PCR assays (hpd#1 and hpd#3) and the conventional iga PCR assay were equally efficient at differentiating study-defined NTHi from Hh, each with a receiver operator characteristic curve area of 0.90 [0.83; 0.98]. The hpd#1 and hpd#3 assays were completely specific against a panel of common respiratory bacteria, unlike the iga PCR, and the hpd#3 assay was able to detect below 10 copies per reaction. Our data suggest an evolutionary continuum between NTHi and Hh and therefore no single gene target could completely differentiate NTHi from Hh. The hpd#3 real time PCR assay proved to be the superior method for discrimination of NTHi from closely related Haemophilus species with the added potential for quantification of H. influenzae directly from specimens. We suggest the hpd#3 assay would be suitable for routine NTHi surveillance and to assess the impact of antibiotics and vaccines, on H. influenzae carriage rates, carriage density, and disease.

  11. Duplex Quantitative PCR Assay for Detection of Haemophilus influenzae That Distinguishes Fucose- and Protein D-Negative Strains.

    Science.gov (United States)

    de Gier, Camilla; Pickering, Janessa L; Richmond, Peter C; Thornton, Ruth B; Kirkham, Lea-Ann S

    2016-09-01

    We have developed a specific Haemophilus influenzae quantitative PCR (qPCR) that also identifies fucose-negative and protein D-negative strains. Analysis of 100 H. influenzae isolates, 28 Haemophilus haemolyticus isolates, and 14 other bacterial species revealed 100% sensitivity (95% confidence interval [CI], 96% to 100%) and 100% specificity (95% CI, 92% to 100%) for this assay. The evaluation of 80 clinical specimens demonstrated a strong correlation between semiquantitative culture and the qPCR (P < 0.001). Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  12. PnuC and the Utilization of the Nicotinamide Riboside Analog 3-Aminopyridine in Haemophilus influenzae

    OpenAIRE

    Sauer, Elizabeta; Merdanovic, Melisa; Price Mortimer, Anne; Bringmann, Gerhard; Reidl, Joachim

    2004-01-01

    The utilization pathway for the uptake of NAD and nicotinamide riboside was previously characterized for Haemophilus influenzae. We now report on the cellular location, topology, and substrate specificity of PnuC. pnuC of H. influenzae is only distantly related to pnuC of Escherichia coli and Salmonella enterica serovar Typhimurium. When E. coli PnuC was expressed in an H. influenzae pnuC mutant, it was able to take up only nicotinamide riboside and not nicotinamide mononucleotide. Therefore,...

  13. Bone and Joint Infections due to Haemophilus parainfluenzae: Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Conar R. O’Neil

    2016-01-01

    Full Text Available Haemophilus parainfluenzae is a normal inhabitant of the human respiratory tract. However it is an increasingly recognized pathogen in invasive infections, particularly in the immunocompromised host and where there is disruption of the normal skin or mucosal barriers. We present a case of a 56-year-old female with a history of asplenia who developed H. parainfluenzae septic arthritis of the hip following an intra-articular steroid injection. We also summarize previously reported cases of bone and joint infections caused by H. parainfluenzae.

  14. Haemophilus influenzae type b diseases in children: a pre-vaccination study.

    Science.gov (United States)

    Bakir, M; el-Khadir, A; Devadas, K; Farrukh, A S; Uduman, S A

    2001-01-01

    Haemophilus influenzae type b (Hib) can now be prevented by vaccination. We present the clinical and laboratory characteristics of acute invasive H. influenzae diseases in children admitted over a 4-year period to a tertiary paediatric ward of the Al-Ain medical district hospital, before vaccination became available in the United Arab Emirates. In all, 38 children had bacteriologically proven H. influenzae invasive diseases and all the isolates were serotype b. Meningitis was diagnosed in 60.5% of the children and 66% of the studied children were under 12 months. There were no deaths but substantial morbidity occurred in 12 children.

  15. Haemophilus parainfluenzae Endocarditis Associated With Maxillary Sinusitis and Complicated by Cerebral Emboli in a Young Man

    Directory of Open Access Journals (Sweden)

    Anthony E. Duzenli MD

    2017-04-01

    Full Text Available HACEK endocarditis is often difficult to diagnose given the slow-growing characteristics of the organisms involved. Haemophilus parainfluenzae, one of the HACEK organisms, is an uncommon cause of endocarditis. We describe a case of a previously healthy young man with H parainfluenzae endocarditis that was associated with maxillary sinusitis and severe systemic complications, including septic cerebral emboli and mitral valve perforation. Previously reported cases have also described a predilection for younger people, cardiac valve pathology, and a high prevalence of stroke.

  16. Impact of the Haemophilus influenzae type b vaccination program on HIB meningitis in Brazil.

    Science.gov (United States)

    Miranzi, Sybelle de Souza Castro; de Moraes, Suzana Alves; de Freitas, Isabel Cristina Martins

    2007-07-01

    This study aimed to evaluate the impact of vaccination against Haemophilus influenzae type b (HIB) in Brazil on the morbidity, mortality, and case fatality of HIB meningitis, using the Ministry of Health database and population data from the Brazilian Institute of Geography and Statistics (Instituto Brasileiro de Geografia e Estatística--IBGE). Impact was evaluated through a time series analysis (1983-2002), using regression forecasting (RF) by dividing the time series into two periods: (a) historical (1983-1998) and (b) validation (1999-2002). Impact of the vaccination was positive, although more significant for incidence and mortality than for case fatality rates.

  17. [Isolation of Haemophilus influenzae serotypes from deep sites in sick children].

    Science.gov (United States)

    Gatti, B M; Ramirez Gronda, G A; Etchevarría, M; Vescina, C M; Varea, A M; González Ayala, S E

    2004-01-01

    Haemophilus influenzae (Hi) is the causative agent of several human diseases such as sepsis, meningitis, celulitis, and osteoarthritis. We investigated the isolation of Hi serotypes from sterile sites in sick children. One hundred and seventy nine strains from 146 patients were studied, period 1996-2002, at the Microbiology Laboratory, Hospital de Niños Superiora Sor María Ludovica, Argentina. The serotype distribution was:1 a, 112 b,1 c,1 d, 4 e, 3 f y 24 no typable. Since the beginning of universal Hi b vaccination in 1998, we have observed the fast decrease of serotype b and a relative increase of other serotypes.

  18. Clonal relationship of recent invasive Haemophilus influenzae serotype f isolates from Denmark and the United States

    DEFF Research Database (Denmark)

    Bruun, B; Gahrn-Hansen, B; Westh, H

    2004-01-01

    Surveillance performed after the introduction of general Haemophilus influenzae serotype b (Hib) vaccination in Denmark identified 13 cases of invasive bacteraemic H. influenzae serotype f (Hif) disease in adults over a period of 7 years. Bacteraemic respiratory tract infections accounted for 61...... % of cases, but meningitis, epiglottitis and osteoarthritis were also seen. Recent Danish isolates were compared to recent American isolates, historical Hif strains and non-Hif invasive strains. Results of conventional serotyping were confirmed by PCR detection of the serotype-f-specific cap and bexA gene...

  19. Non-typeable Haemophilus influenzae purulent pericarditis in a child with cystic fibrosis.

    Science.gov (United States)

    Downes, Kevin J; Abulebda, Kamal; Siracusa, Christopher; Moore, Ryan; Staat, Mary A; Poynter, Sue E

    2016-07-01

    Early airway colonization and infection with Haemophilus influenzae in children with cystic fibrosis (CF) is common. Although the pathogenicity of non-typeable H. influenzae (NTHi) in patients with CF is controversial, this organism can cause both upper and lower respiratory tract infections. Extra-pulmonary disease, however, is rare. Purulent pericarditis is a suppurative complication of bacterial infection of the pericardial space that can arise as a result of direct extension from an adjacent infection. We describe a case of purulent pericarditis due to NTHi in a young child with CF that developed as a complication of inadequately treated bronchopneumonia. © 2016 Japan Pediatric Society.

  20. Haemophilus parainfluenzae Strain ATCC 33392 Forms Biofilms In Vitro and during Experimental Otitis Media Infections.

    Science.gov (United States)

    Pang, Bing; Swords, W Edward

    2017-09-01

    Haemophilus parainfluenzae is a nutritionally fastidious, Gram-negative bacterium with an oropharyngeal/nasopharyngeal carriage niche that is associated with a range of opportunistic infections, including infectious endocarditis and otitis media (OM). These infections are often chronic/recurrent in nature and typically involve bacterial persistence within biofilm communities that are highly resistant to host clearance. This study addresses the primary hypothesis that H. parainfluenzae forms biofilm communities that are important determinants of persistence in vivo The results from in vitro biofilm studies confirmed that H. parainfluenzae formed biofilm communities within which the polymeric matrix was mainly composed of extracellular DNA and proteins. Using a chinchilla OM infection model, we demonstrated that H. parainfluenzae formed surface-associated biofilm communities containing bacterial and host components that included neutrophil extracellular trap (NET) structures and that the bacteria mainly persisted in these biofilm communities. We also used this model to examine the possible interaction between H. parainfluenzae and its close relative Haemophilus influenzae, which is also commonly carried within the same host environments and can cause OM. The results showed that coinfection with H. influenzae promoted clearance of H. parainfluenzae from biofilm communities during OM infection. The underlying mechanisms for bacterial persistence and biofilm formation by H. parainfluenzae and knowledge about the survival defects of H. parainfluenzae during coinfection with H. influenzae are topics for future work. Copyright © 2017 American Society for Microbiology.

  1. Comparative virulence of Haemophilus parasuis serovars 1 to 7 in guinea pigs.

    Science.gov (United States)

    Rapp-Gabrielson, V J; Gabrielson, D A; Schamber, G J

    1992-06-01

    Reference strains for Haemophilus parasuis serovars 1 to 7 were examined for virulence by inoculation of guinea pigs. Guinea pig response to intraperitoneal inoculation was similar for the 7 reference strains. However, apparent differences in virulence were detected after intratracheal inoculation. Cells of the references strains for serovars 1 and 5 were most invasive, causing moribundity or death at higher doses and a persistent septicemia at lower doses. Haemophilus parasuis could be isolated from respiratory and systemic sites; purulent bronchopneumonia, pericarditis, and pleuritis were apparent in infected guinea pigs. Inoculation of cells of the reference strains for serovars 2 and 6 also resulted in bronchopneumonia and moribundity or death in some guinea pigs; however, reisolation of H parasuis and microscopic lesions at necropsy were less pronounced than those observed with serovars 1 and 5. Inoculation of cells of serovars 3, 4 and 7 induced only transient clinical signs and minimal evidence of H parasuis infection at necropsy. The data from intratracheal inoculation of guinea pigs are similar to data from other investigations in swine, indicating differences in the pathogenic potential of H parasuis strains. Thus, guinea pigs may be useful as a laboratory animal model for examining cellular factors associated with virulence and immunogenicity of H parasuis.

  2. Genetic organisation of the capsule transport gene region from Haemophilus paragallinarum

    Directory of Open Access Journals (Sweden)

    O. De Smidt

    2004-11-01

    Full Text Available The region involved in export of the capsule polysaccharides to the cell surface of Haemophilus paragallinarum was cloned and the genetic organisation determined. Degenerate primers designed from sequence alignment of the capsule transport genes of Haemophilus influenzae, Pasteurella multocida and Actinobacillus pleuropneumoniae were used to amplify a 2.6 kb fragment containing a segment of the H. paragallinarum capsule transport gene locus. This fragment was used as a digoxigenin labelled probe to isolate the complete H. paragallinarum capsule transport gene locus from genomic DNA. The sequence of the cloned DNA was determined and analysis revealed the presence of four genes, each showing high homology with known capsule transport genes. The four genes were designated hctA, B, C and D (for H. paragallinarum capsule transport genes and the predicted products of these genes likely encode an ATP-dependent export system responsible for transport of the capsule polysaccharides to the cell surface, possibly a member of a super family designated ABC (ATP-binding cassette transporters.

  3. Structure of the N-terminal region of Haemophilus Influenzae HI0017: Implications for function

    Energy Technology Data Exchange (ETDEWEB)

    Yu Liping; Mack, Jamey; Hajduk, Phil; Fesik, Stephen W. [Abbott Laboratories, Pharmaceutical Discovery Division, D46Y, AP10/LL (United States)

    2001-06-15

    Haemophilus influenzae is a gram-negative pathogen that causes infections ranging from asymptomatic colonization of the human upper respiratory tract to serious invasive diseases such as meningitis. Although the genome of Haemophilus influenzae has been completely sequenced, the structure and function of many of these proteins are unknown. HI0017 is one of these uncharacterized proteins. Here we describe the three-dimensional solution structure of the N-terminal portion of HI0017 as determined by NMR spectroscopy. The structure consists of a five-stranded antiparallel {beta}-sheet and two short {alpha}-helices. It is similar to the C-terminal domain of Diphtheria toxin repressor (DtxR). The C-terminal portion of HI0017 has an amino acid sequence that closely resembles pyruvate formate-lyase - an enzyme that converts pyruvate and CoA into acetyl-CoA and formate by a radical mechanism. Based on structural and sequence comparisons, we propose that the C-terminus of HI0017 functions as an enzyme with a glycyl radical mechanism, while the N-terminus participates in protein/protein interactions involving an activase (iron-sulfur protein) and/or the substrate.

  4. Evaluation of introduction of the Haemophilus influenzae vaccine in Côte d’Ivoire

    Science.gov (United States)

    Yohou, Kévin Sylvestre; Aka, Nicaise Lepri; Noufe, Soualihou; Douba, Alfred; Assi Assi, Bernard; Dagnan, Simplice N Cho

    2016-11-25

    Introduction: Côte d’Ivoire introduced the Haemophilus influenzae type b vaccine into the EPI in March 2009. Following this introduction, an evaluation was conducted in 2012 in order to evaluate the vaccine introduction process. Methods: Data collection methods consisted of document review, structured interviews and direct observation. This study collected information from six health region officials, 12 health districts and 36 healthcare institutions. Seventy-two mothers or child carers were also interviewed. Collected data were processed and analysed by Excel, Epi Info and SPSS. Results: A vaccine introduction plan was developed, but was not communicated at the operational level. The planned training for district health care providers was conducted eighteen months after introduction of the vaccine. None of the vaccinating centres had communication support about the new vaccine. Temperature recording was regularly performed in 92% of district deposits and 68% of vaccinating centres. Deteriorated vaccines were observed in 6% of vaccinating centres. Only 3.5% of parents had been informed about introduction of the vaccine. Increased immunization coverage for the third dose of pentavalent vaccine was observed in one half of health districts. Conclusion: Evaluation of the introduction of Haemophilus influenzae type b vaccine highlightsthe strengths and weaknesses of the health system and provides lessons for the introduction of other vaccines into the expanded programme on immunization.

  5. Solithromycin inhibition of protein synthesis and ribosome biogenesis in Staphylococcus aureus, Streptococcus pneumoniae, and Haemophilus influenzae.

    Science.gov (United States)

    Rodgers, Ward; Frazier, Ashley D; Champney, W Scott

    2013-04-01

    The continuing increase in antibiotic-resistant microorganisms is driving the search for new antibiotic targets and improved antimicrobial agents. Ketolides are semisynthetic derivatives of macrolide antibiotics, which are effective against certain resistant organisms. Solithromycin (CEM-101) is a novel fluoroketolide with improved antimicrobial effectiveness. This compound binds to the large 50S subunit of the ribosome and inhibits protein biosynthesis. Like other ketolides, it should impair bacterial ribosomal subunit formation. This mechanism of action was examined in strains of Streptococcus pneumoniae, Staphylococcus aureus, and Haemophilus influenzae. The mean 50% inhibitory concentrations (IC50s) for solithromycin inhibition of cell viability, protein synthesis, and growth rate were 7.5, 40, and 125 ng/ml for Streptococcus pneumoniae, Staphylococcus aureus, and Haemophilus influenzae, respectively. The net formation of the 50S subunit was reduced in all three organisms, with IC50s similar to those given above. The rates of 50S subunit formation measured by a pulse-chase labeling procedure were reduced by 75% in cells growing at the IC50 of solithromycin. Turnover of 23S rRNA was stimulated by solithromycin as well. Solithromycin was found to be a particularly effective antimicrobial agent, with IC50s comparable to those of telithromycin and significantly better than those of azithromycin and clarithromycin in these three microorganisms.

  6. Treatment of Haemophilus bacteremia with benzylpenicillin is associated with increased (30-day mortality

    Directory of Open Access Journals (Sweden)

    Thønnings Sara

    2012-07-01

    Full Text Available Abstract Background Optimal antibiotic treatment strategies of Haemophilus infections are still needed. Therefore, 30-day case fatality rate (CFR of Haemophilus bacteremia and efficacy of various antibiotic treatment regimes were studied. Methods All episodes of Haemophilus bacteremia in the former Copenhagen County during the period 2000-9 were included in the study. Clinical and biochemical findings and outcome were collected retrospectively from medical records. Results 105 consecutive episodes were identified (median age: 69 years, with only 4 children H. influenzae, and 11% to other Haemophilus species. Pneumonia was the most common primary focus (in 48%, and 58% of the patients had Charlson comorbidity index > 1. Definitive antibiotic therapy was in 26 cases benzylpenicillin, in 12 cases aminopenicillins, in 50 cases cefuroxime and in 16 cases broadspectrum antibiotics, whereas 1 palliative case died without start of therapy. Whereas the use of broadspectrum antibiotics was related to the severity of the disease (admittance to ICU, need for assisted ventilation or hemodialysis, septic shock, no significant difference in clinical features was demonstrated for therapy with benzylpenicillin, aminopenicillin or cefuroxime, except benzylpenicillin was rarely administered to immunosuppressed patients. The CFR was 22% (23/105. The choice of empiric antibiotic therapy was not significantly associated with mortality (adequate vs. inadequate treatment: 23% (21/93 vs. 17% (2/12, respectively, P > 0.05. In contrast, definite antibiotic therapy with cefuroxime or aminopenicillins resulted in a significantly lower CFR than treatment with benzylpenicillin (12% (6/50 or 0% (0/12 vs. 39% (10/26, respectively, Log rank test P  0.02. When adjustments were made for other identified risk factors in bivariate logistic regression analysis, treatment with cefuroxime was still were found to be associated with a significantly lower CFR than for

  7. Identification of a group of Haemophilus influenzae penicillin-binding proteins that may have complementary physiological roles

    Energy Technology Data Exchange (ETDEWEB)

    Malouin, F.; Parr, T.R. Jr.; Bryan, L.E. (Eli Lilly Company, Indianapolis, IN (USA))

    1990-02-01

    (35S)penicillin bound to different Haemophilus influenzae proteins in assays performed at 20, 37, or 42{degrees}C. Penicillin-binding proteins 3a, 3b, 4, and 4' formed a group characterized by their affinity for moxalactam, cefotaxime, and piperacillin. Penicillin-binding protein 4' showed specific properties that may reflect its complementary role in septation.

  8. Towards a sustainable, quality and affordable Haemophilus influenzae type b vaccine for every child in the world

    NARCIS (Netherlands)

    Hamidi, A.

    2016-01-01

    Haemophilus influenzae type b (Hib) conjugate vaccine is a safe and effective vaccine that can prevent meningitis and pneumonia caused by Hib disease. Hib vaccine is recommended for all children under 5 years. Despite the availability of safe and effective Hib vaccines since early 1987, Gambia was

  9. Haemophilus influenzae localized in epithelial cell layers is shielded from antibiotics and antibody-mediated bactericidal activity

    NARCIS (Netherlands)

    van Schilfgaarde, M.; Eijk, P.; Regelink, A.; van Ulsen, P.; Everts, V.; Dankert, J.; van Alphen, L.

    1999-01-01

    Nonencapsulated Haemophilus influenzae frequently persists in the lungs of chronic obstructive pulmonary disease (COPD) and cystic fibrosis (CF) patients for prolonged periods of time. The bacteria are not eradicated by antibiotic treatment of the patients or by specific antibodies that are found in

  10. MIC quality control guidelines for Haemophilus susceptibility tests using cefdinir (FK482), cefepime, cefetamet, cefpirome, ceftibuten, fleroxacin, temafloxacin, clarithromycin, RP59500, and trospectomycin.

    Science.gov (United States)

    Bale, M J; Jones, R N; Erwin, M E; Koontz, F P; Gerlach, E H; Murray, P R; Washington, J A

    1992-01-01

    A multilaboratory study was performed to establish broth microdilution MIC quality control (QC) guidelines for 10 investigational drugs which previously demonstrated significant activity against Haemophilus influenzae. MIC QC ranges for H. influenzae ATCC 49247 with Haemophilus test medium were determined by using multiple contemporary lots of Haemophilus test medium and the National Committee for Clinical Laboratory Standards' recommended numbers of replicate tests. On the basis of these results, QC ranges (generally modal MIC +/- one log2 dilution) are proposed for cefdinir, cefepime, cefetamet, cefpirome, ceftibuten, fleroxacin, temafloxacin, clarithromycin, RP59500, and trospectomycin. The proposed QC guidelines for clarithromycin and temafloxacin were recently accepted by the National Committee for Clinical Laboratory Standards. PMID:1310329

  11. [Multicenter prospective epidemiological studies on Haemophilus influenzae infection among hospitalized children with lower respiratory tract infections].

    Science.gov (United States)

    Hu, Jun; Wang, Xiaolei; Ai, Tao; Xie, Xiaoping; Liu, Xiaoyun; Liu, Huawei; Yang, Lili; Li, Hua; Yang, Taoyi; Zhang, Tong; Zhang, Li; Yang, Zhao; Deng, Quanmin

    2016-02-01

    To understand epidemiological characteristics of Haemophilus influenzae (Hi) infection in hospitalized children with lower respiratory tract infection (LRTI) in west Sichuan China. The multicenter prospective cross-sectional design was used; four hospitals in west Sichuan China were chosen as research field, sputum bacterial culture was done and biological typing, PCR identification and drug sensitivity test of Hi epidemic strains were carried out among 0-17y hospitalized patients with LRTI in four hospitals located in west Sichuan China. Totally 5 748 cases with LRTI in four hospitals were investigated in west Sichuan from Nov. 2013 to April 2014 and the rate of sputum culture was 46.96% (2,699/5 748). The total pathogenic bacteria positive rate of sputum culture was 43.53% (1,175/2 699), and 279 Haemophilus influenzae (Hi) strain in 272 cases were isolated, the Hi positive rate was 10.08% (272/2 699). All the strains (100%) were non-typeable Haemophilus influenzae (NTHi ) indentified by PCR. The main biotype of 279 strains was type Ⅰ with 39.07% (109/279) and type Ⅳ with 50.90% (142/279) ; 272 cases were enrolled in this survey, 12.50% (34/272) had broncheolitis, the rest of lower respiratory infection was 87.50 % (238/272), and 2.57% (7/272) was neonatal pneumonia, 2.21%(6/272)was pneumonia complicated with sepsis; in four hospitals the overall positive rate of Hi in inpatients with lower respiratory infection was 10.21%, 28.96%, 4.80%, 10.21% (χ(2) = 112.561, P = 0.000) and the positive rate of Hi inpatients with broncheolitis was 11.92%, 20.93%, 4.76%, and 66.67% (Fisher exact probability P = 0.001), with the rest lower respiratory infection was 9.96%, 30.90%, 4.81%, 9.85% (χ(2) =108.876, P = 0.000); 2.87% (8/279) bacterial strains of β-lactamase-nonproducing-ampicillin-intermediary (BLNAI) distributed in four hospitals, and 1.79% (5/279) bacterial strains of β-lactamase-nonproducing-ampicillin-resistant (BLNAR), 0.72% (2/279) bacterial strains of

  12. Molecular surveillance of true nontypeable Haemophilus influenzae: an evaluation of PCR screening assays.

    Directory of Open Access Journals (Sweden)

    Michael J Binks

    Full Text Available BACKGROUND: Unambiguous identification of nontypeable Haemophilus influenzae (NTHi is not possible by conventional microbiology. Molecular characterisation of phenotypically defined NTHi isolates suggests that up to 40% are Haemophilus haemolyticus (Hh; however, the genetic similarity of NTHi and Hh limits the power of simple molecular techniques such as PCR for species discrimination. METHODOLOGY/PRINCIPAL FINDINGS: Here we assess the ability of previously published and novel PCR-based assays to identify true NTHi. Sixty phenotypic NTHi isolates, classified by a dual 16S rRNA gene PCR algorithm as NTHi (n = 22, Hh (n = 27 or equivocal (n = 11, were further characterised by sequencing of the 16S rRNA and recA genes then interrogated by PCR-based assays targeting the omp P2, omp P6, lgtC, hpd, 16S rRNA, fucK and iga genes. The sequencing data and PCR results were used to define NTHi for this study. Two hpd real time PCR assays (hpd#1 and hpd#3 and the conventional iga PCR assay were equally efficient at differentiating study-defined NTHi from Hh, each with a receiver operator characteristic curve area of 0.90 [0.83; 0.98]. The hpd#1 and hpd#3 assays were completely specific against a panel of common respiratory bacteria, unlike the iga PCR, and the hpd#3 assay was able to detect below 10 copies per reaction. CONCLUSIONS/SIGNIFICANCE: Our data suggest an evolutionary continuum between NTHi and Hh and therefore no single gene target could completely differentiate NTHi from Hh. The hpd#3 real time PCR assay proved to be the superior method for discrimination of NTHi from closely related Haemophilus species with the added potential for quantification of H. influenzae directly from specimens. We suggest the hpd#3 assay would be suitable for routine NTHi surveillance and to assess the impact of antibiotics and vaccines, on H. influenzae carriage rates, carriage density, and disease.

  13. Lack of Virus-Specific Bacterial Adherence to Bovine Embryonic Lung Cells Infected with Bovine Parainfluenza Virus Type 3 †

    OpenAIRE

    Toth, Thomas E.; Gates, Connie

    1983-01-01

    Infection of bovine embryonic lung cells with bovine parainfluenza virus type 3 did not induce in vitro, virus-specific, hemadsorption-related adherence of Corynebacterium pyogenes, Haemophilus somnus, Staphylococcus aureus, Streptococcus zooepidemicus, Pasteurella haemolytica, Listeria monocytogenes, Escherichia coli, Pasteurella multocida, Brucella sp., or Salmonella typhimurium.

  14. Author Details

    African Journals Online (AJOL)

    Umoh, VJ. Vol 56, No 2 (2008) - Articles Evaluation of rumen ingesta based-diet as alternative feed stuff for growing rabbits. Abstract · Vol 56, No 3 (2008) - Articles Isolation Of Haemophilus Somnus From Pneumonic Lung In Slaughtered White Fulani Cattle In Jos, Nigeria Abstract. ISSN: 0378-9721. AJOL African Journals ...

  15. Synergistic effect of interleukin 1 alpha on nontypeable Haemophilus influenzae-induced up-regulation of human beta-defensin 2 in middle ear epithelial cells

    Directory of Open Access Journals (Sweden)

    Park Raekil

    2006-01-01

    Full Text Available Abstract Background We recently showed that beta-defensins have antimicrobial activity against nontypeable Haemophilus influenzae (NTHi and that interleukin 1 alpha (IL-1 alpha up-regulates the transcription of beta-defensin 2 (DEFB4 according to new nomenclature of the Human Genome Organization in human middle ear epithelial cells via a Src-dependent Raf-MEK1/2-ERK signaling pathway. Based on these observations, we investigated if human middle ear epithelial cells could release IL-1 alpha upon exposure to a lysate of NTHi and if this cytokine could have a synergistic effect on beta-defensin 2 up-regulation by the bacterial components. Methods The studies described herein were carried out using epithelial cell lines as well as a murine model of acute otitis media (OM. Human cytokine macroarray analysis was performed to detect the released cytokines in response to NTHi exposure. Real time quantitative PCR was done to compare the induction of IL-1 alpha or beta-defensin 2 mRNAs and to identify the signaling pathways involved. Direct activation of the beta-defensin 2 promoter was monitored using a beta-defensin 2 promoter-Luciferase construct. An IL-1 alpha blocking antibody was used to demonstrate the direct involvement of this cytokine on DEFB4 induction. Results Middle ear epithelial cells released IL-1 alpha when stimulated by NTHi components and this cytokine acted in an autocrine/paracrine synergistic manner with NTHi to up-regulate beta-defensin 2. This synergistic effect of IL-1 alpha on NTHi-induced beta-defensin 2 up-regulation appeared to be mediated by the p38 MAP kinase pathway. Conclusion We demonstrate that IL-1 alpha is secreted by middle ear epithelial cells upon exposure to NTHi components and that it can synergistically act with certain of these molecules to up-regulate beta-defensin 2 via the p38 MAP kinase pathway.

  16. Killing curve activity of ciprofloxacin is comparable to synergistic effect of beta-lactam-tobramycin combinations against Haemophilus species endocarditis strains

    DEFF Research Database (Denmark)

    Westh, H; Frimodt-Møller, N; Gutschik, E

    1992-01-01

    Nine Haemophilus species strains, all beta-lactamase negative, isolated from patients with endocarditis were tested in killing curve experiments. Antibiotics used were penicillin, amoxicillin, aztreonam alone and in combination with tobramycin, as well as ciprofloxacin alone. Synergism between be...

  17. Predictors for Haemophilus influenzae colonization, antibiotic resistance and for sharing an identical isolate among children attending 16 licensed day-care centers in Michigan.

    Science.gov (United States)

    Barbosa-Cesnik, Cibele; Farjo, Rand S; Patel, May; Gilsdorf, Janet; McCoy, Sandra I; Pettigrew, Melinda M; Marrs, Carl; Foxman, Betsy

    2006-03-01

    Nontypable Haemophilus influenzae is an important cause of otitis media in children. Children attending day-care centers are at an increased risk for nontypable H. influenzae colonization and otitis media. We describe the prevalence of nontypable H. influenzae colonization, antibiotic resistance and predictors for colonization and sharing an identical isolate with at least 1 other child in the same day-care centers among children attending 16 day-care centers. Throat swabs of 198 children antibiotic resistance and genotyped. Statistics were performed using SAS software (SAS Institute, Inc., Cary, NC). We isolated 179 unique nontypable H. influenzae strains from 127 participants. Colonization ranged from 0% to 95% among day-care centers. As individual factors, exposure to tobacco smoke was associated with colonization (P = 0.05), and racial self-identifications as "other" (nonwhite, nonblack) was protective (P = 0.035), whereas as "black" was protective for sharing (P = 0.03). Pacifier use was associated with sharing (P = 0.04), but not with colonization. As day-care centers factors, rates of colonization and sharing were higher in day-care centers with > or = 5 classrooms (P resistant strains if they were taking an antibiotic (P = 0.02). Although day-care center colonization varied, the overall colonization rate was high. Colonization with nontypable H. influenzae, with beta-lactamase-producing strain and sharing were, mostly, associated with modifiable risk factors.

  18. Development of an improved species specific PCR test for detection of Haemophilus parasuis

    DEFF Research Database (Denmark)

    Angen, Øystein; Oliveira, Simone; Ahrens, Peter

    2007-01-01

    A PCR test for identification of Haemophilus parasuis was optimized using the 16S rDNA sequences of the 15 serotype reference strains of H. parasuis. The test was evaluated on a collection of 218 Danish field isolates as well as on 81 representatives of 27 other species, including genetically...... affiliated species within Pasteurellaceae. In addition, DNA preparations from 56 H. parasuis isolates from North America were included. To obtain a test that was specific for H. parasuis, a multiplex PCR using 3 different primers was developed. The PCR test produced an amplicon of approximately 1090 bp only...... with representatives of H. parasuis. The test was further evaluated on 55 clinical samples from 16 Danish pigs suspected for being infected with H. parasuis, showing polyserositis or septicemia at autopsy as well as on 492 nasal swabs. The test was compared with the performance of a PCR test earlier published...

  19. Acute septic arthritis of the acromioclavicular joint caused by Haemophilus parainfluenzae: a rare causative origin.

    Science.gov (United States)

    Hong, Myong-Joo; Kim, Yeon-Dong; Ham, Hyang-Do

    2015-04-01

    Septic arthritis of the acromioclavicular (AC) joint is a rare entity with symptoms that include erythema, swelling, and tenderness over the AC joint, fever, and limitation of shoulder motion with pain. In previous reports, Staphylococcus and Streptococcus species have been mentioned as common causative organisms. Haemophilus parainfluenzae is a normal inhabitant of the oral cavity, respiratory tract, gastrointestinal tract, and urogenital tract. However, it sometimes causes opportunistic infections leading to septic arthritis and osteomyelitis. AC joint infection associated with H.parainfluenzae is very rare, and only one case has been reported in the literature. Moreover, septic arthritis in immunocompetent patients is also very rare. Here, we report the case of a healthy patient with H. parainfluenzae-related septic arthritis of the AC joint.

  20. Map-based comparative genomic analysis of virulent haemophilus parasuis serovars 4 and 5.

    Science.gov (United States)

    Lawrence, Paulraj; Bey, Russell

    2015-01-01

    Haemophilus parasuis is a commensal bacterium of the upper respiratory tract of healthy pigs. However, in conjunction with viral infections in immunocompromised animals H. parasuis can transform into a pathogen that is responsible for causing Glasser's disease which is typically characterized by fibrinous polyserositis, polyarthritis, meningitis and sometimes acute pneumonia and septicemia in pigs. Haemophilus parasuis serovar 5 is highly virulent and more frequently isolated from respiratory and systemic infection in pigs. Recently a highly virulent H. parasuis serovar 4 was isolated from the tissues of diseased pigs. To understand the differences in virulence and virulence-associated genes between H. parasuis serovar 5 and highly virulent H. parasuis serovar 4 strains, a genomic library was generated by TruSeq preparation and sequenced on Illumina HiSeq 2000 obtaining 50 bp PE reads. A three-way comparative genomic analysis was conducted between two highly virulent H. parasuis serovar 4 strains and H. parasuis serovar 5. Haemophilus parasuis serovar 5 GenBank isolate SH0165 (GenBank accession number CP001321.1) was used as reference strain for assembly. Results of these analysis revealed the highly virulent H. parasuis serovar 4 lacks genes encoding for, glycosyl transferases, polysaccharide biosynthesis protein capD, spore coat polysaccharide biosynthesis protein C, polysaccharide export protein and sialyltransferase which can modify the lipopolysaccharide forming a short-chain LPS lacking O-specific polysaccharide chains often referred to as lipooligosaccharide (LOS). In addition, it can modify the outer membrane protein (OMP) structure. The lack of sialyltransferase significantly reduced the amount of sialic acid incorporated into LOS, a major and essential component of the cell wall and an important virulence determinant. These molecules may be involved in various stages of pathogenesis through molecular mimicry and by causing host cell cytotoxicity, reduced

  1. Genome-Wide Association Studies of Virulent and Avirulent Haemophilus parasuis Serotype 4 Strains.

    Science.gov (United States)

    Lawrence, Paulraj K; Wiener, Brittanny L; Kolander-Bremer, Tammy; Bey, Russell F; Stine, Douglas L; Kittichotirat, Weerayuth; Bumgarner, Roger E

    2014-09-04

    Haemophilus parasuis is a normal commensal of the upper respiratory tract of healthy pigs. However, in conjunction with stress and/or viral infections, or in immunocompromised animals, H. parasuis can transform into a pathogen causing Glasser's disease, which is typically characterized by fibrinous polyserositis, polyarthritis, meningitis, and sometimes acute pneumonia and septicemia. H. parasuis serotype 5 is highly virulent and more frequently isolated from respiratory and systemic infection in pigs. Recently Newport Laboratories isolated highly virulent H. parasuis serotype 4 strains from the tissues of diseased pigs. This study was undertaken to identify the genes responsible for H. parasuis serotype 4 virulence. To achieve this objective we performed genome-wide association studies (GWAS) across two virulent and three avirulent H. parasuis serotype 4 strains. Copyright © 2014 Lawrence et al.

  2. Intervertebral discitis caused by nontypeable Haemophilus influenzae in an adult: Case report

    Science.gov (United States)

    Boulton, R.; Swayamprakasam, A.; Raza, M.

    2012-01-01

    INTRODUCTION: Haemophilus influenzae is a common cause of bacterial meningitis in children and can cause upper respiratory tract infections in adults, but has yet to be reported solely involving intervertebral discitis. PRESENTATION OF CASE: A 67-year-old builder presenting with fever, myalgia and back pain is found to have intervertebral discitis (confirmed on MRI) caused by H. influenzae (identified on blood cultures). DISCUSSION: A nontypeable form of H. influenzae has not been reported causing discitis. We describe a case in a relatively fit individual who was treated successfully with antimicrobial treatment. A preceding upper respiratory tract infection is the presumed source of infection, predisposed by long-term low-dose steroid therapy. CONCLUSION: H. influenzae is a rare, but treatable cause of discitis. PMID:22466113

  3. Cell vacuolation induced by Haemophilus influenzae supernatants in HEp-2 cells

    Directory of Open Access Journals (Sweden)

    Maria del Rosario Espinoza-Mellado

    2013-12-01

    Full Text Available Haemophilus influenzae belongs to respiratory tract microbiota. We observed vacuoles formation in previous studies with H. influenzae culture supernatants, so in this work we characterised that cytotoxic effect. We observed an abundant production of acidic cytoplasmic vacuoles due to the presence of a “vacuolating factor” in H. influenzae supernatants which was characterised as thermolabile. Greatest vacuolating activity was observed when utilizing the fraction > 50 kDa. The presence of a large number of vacuoles in HEp-2 cells was verified by transmission electron microscopy and some vacuoles were identified with a double membrane and/or being surrounded by ribosomes. These results suggest similar behaviour to that of vacuolating effects described by autotransporter proteins an undescribed cytotoxic effect induced by H. influenzae .

  4. Clinical characteristics of Haemophilus influenzae meningitis in Denmark in the post-vaccination era

    DEFF Research Database (Denmark)

    Pedersen, T.I.; Howitz, Michael Frantz; Andersen, Christian Østergaard

    2010-01-01

    P>The introduction of Haemophilus influenzae type b (Hib) vaccine into the Danish childhood vaccination programme in 1993 may have influenced the epidemiology of H. influenzae meningitis (i.e. increasing frequency of other non-vaccine types; presentation in other age groups). Based on nationwide...... infected with Hib, two cases (13%) were identified as true vaccine failures. Six patients (9%) died; one premature infant infected with serotype f and five adults (age 83-96 years) with non-typeable H. influenzae. Hearing loss was reported in 16% of the surviving children and in 10% of the surviving adults...... registration, clinical information and laboratory findings were collected from all 65 confirmed cases of H. influenzae meningitis during the period 1994-2005. Twenty-nine patients (45%) were 24 years old [median 62 years (range 25...

  5. Serious systemic infection caused by non-encapsulated Haemophilus influenzae biotype III in an adult

    DEFF Research Database (Denmark)

    Lester, Anne; Pedersen, P B

    1991-01-01

    Haemophilus influenzae is the aetiological agent in less than 1% of septic arthritis cases in adults and most often serotype b is involved. We report here a case of severe systemic infection due to non-encapsulated H. influenzae biotype III in a 40-year-old man, previously healthy although alcohol...... abuser. Cholangitis and acute alcoholic hepatitis were diagnosed simultaneously. The organism was grown from blood and from synovial fluid of the left knee, but several other joints were also affected. The close relationship between H. influenzae biotype III and H. aegyptius is mentioned in view...... of recent reports of fatal childhood illness caused by a special clone of H. aegyptius and the importance of reporting both serotype and biotype in severe H. influenzae induced disease is emphasized....

  6. Nontypeable Haemophilus influenzae invasion and persistence in the human respiratory tract

    Directory of Open Access Journals (Sweden)

    Cara eClementi

    2011-11-01

    Full Text Available Nontypeable Haemophilus influenzae (NTHI is an opportunistic bacterial pathogen of the human respiratory tract and is a leading cause of respiratory infections in children and adults. NTHI is considered to be an extracellular pathogen, but has consistently been observed within and between human respiratory epithelial cells and macrophages, in vitro and ex vivo. Until recently, few studies have examined the internalization, trafficking, and fate of NTHI in host cells. It is important to clarify this interaction because of a possible correlation between intracellular NTHI and symptomatic infection, and because NTHI infections frequently persist and recur despite antibiotic therapy and the development of bactericidal antibodies, suggesting a possible intracellular state or reservoir for NTHI. How do NTHI enter host cells? Can NTHI survive intracellularly and, if so, for how long? Strides have been made in the identification of host receptors, signaling, endocytosis, and trafficking pathways involved in the entry and persistence of NTHI in the respiratory tract.

  7. Clinical characteristics of Haemophilus influenzae meningitis in Denmark in the post-vaccination era

    DEFF Research Database (Denmark)

    Pedersen, T.I.; Howitz, M.; Andersen, Christian Østergaard

    2010-01-01

    P>The introduction of Haemophilus influenzae type b (Hib) vaccine into the Danish childhood vaccination programme in 1993 may have influenced the epidemiology of H. influenzae meningitis (i.e. increasing frequency of other non-vaccine types; presentation in other age groups). Based on nationwide...... registration, clinical information and laboratory findings were collected from all 65 confirmed cases of H. influenzae meningitis during the period 1994-2005. Twenty-nine patients (45%) were 24 years old [median 62 years (range 25....... The presence of a lung focus was an independent prognostic factor for an unfavourable outcome (p 0.03). In conclusion, meningitis caused by Hib has been infrequent in Denmark after introduction of the Hib vaccine in the childhood vaccination programme, and no increase in meningitis cases due to non-b type H...

  8. Type IV secretion systems and genomic islands-mediated horizontal gene transfer in Pseudomonas and Haemophilus.

    Science.gov (United States)

    Juhas, Mario

    2015-01-01

    Bacterial secretion systems, such as type IV secretion systems (T4SSs) are multi-subunit machines transferring macromolecules across membranes. Besides proteins, T4SSs also transfer nucleoprotein complexes, thus having a significant impact on the evolution of bacterial species. By T4SS-mediated horizontal gene transfer bacteria can acquire a broad spectrum of fitness genes allowing them to thrive in the wide variety of environments. Furthermore, acquisition of antibiotic-resistance and virulence genes can lead to the emergence of novel 'superbugs'. This review provides an update on the investigation of T4SSs. It highlights the role T4SSs play in the horizontal gene transfer, particularly in the evolution of catabolic pathways, antibiotic-resistance and virulence in Haemophilus and Pseudomonas. Copyright © 2014 Elsevier GmbH. All rights reserved.

  9. Inflammatory response of Haemophilus influenzae biotype aegyptius causing Brazilian Purpuric Fever

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    Gisele Cristiane Gentile Cury

    2014-12-01

    Full Text Available The Brazilian Purpuric Fever (BPF is a systemic disease with many clinical features of meningococcal sepsis and is usually preceded by purulent conjunctivitis. The illness is caused by Haemophilus influenza biogroup aegyptius, which was associated exclusively with conjunctivitis. In this work construction of the las gene, hypothetically responsible for this virulence, were fusioned with ermAM cassette in Neisseria meningitidis virulent strains and had its DNA transfer to non BPF H. influenzae strains. The effect of the las transfer was capable to increase the cytokines TNFα and IL10 expression in Hec-1B cells line infected with these transformed mutants (in eight log scale of folding change RNA expression. This is the first molecular study involving the las transfer to search an elucidation of the pathogenic factors by horizontal intergeneric transfer from meningococci to H. influenzae.

  10. Expression and Purification of Haemophilus influenzae Rhomboid Intramembrane Protease GlpG for Structural Studies.

    Science.gov (United States)

    Panwar, Pankaj; Lemieux, M Joanne

    2014-04-01

    Rhomboid proteases are membrane-embedded proteases that cleave peptide bonds of transmembrane proteins. They play a variety of roles in cell signaling events. The rhomboid protease GlpG from Haemophilus influenzae (hiGlpG) is a canonical form of rhomboid protease having six transmembrane segments. In this unit, detailed protocols are presented for optimization of hiGlpG expression using the araBAD promotor system in the pBAD vector. The parameters for optimization include concentration of inducing agent, induction temperature, and time. Optimization of these key factors led to the development of a protocol yielding 1.6 to 2.5 mg/liter protein purified after ion metal affinity chromatography (IMAC). Further purification can include size exclusion chromatography (SEC). Copyright © 2014 John Wiley & Sons, Inc.

  11. Haemophilus influenzae type B genital infection and septicemia in pregnant woman: a case report

    Directory of Open Access Journals (Sweden)

    Hosuru Subramanya Supram

    2014-06-01

    Full Text Available Haemophilus influenzae (H. influenzae type B a non-motile, aerobic, gram negative cocobacillus is a commensal of upper respiratory tract. Genitourinary infection due to H. influenzae has been reported but bacteremia associated with such infection appears to be rare. We report a case of 19 years young primigravida with complaints of amenorrhea of 32 weeks and 5 days, pyrexia, abdominal pain and blood stained discharge per vaginum. H. influenzae type B was recovered from the genital tract as well as blood of the mother indicating maternal septicemia. Septicemia caused by H. influenzae type B in pregnant women following vaginal colonization and infection is rare. It has been reported in many parts of world over the years; to the best of our knowledge this is the first reported case from Nepal. H. influenzae should be considered as a potential maternal, fetal, and neonatal pathogen.

  12. Vaccination of gnotobiotic primary specific pathogen-free pigs against Haemophilus parasuis.

    Science.gov (United States)

    Miniats, O P; Smart, N L; Ewert, E

    1991-01-01

    Three trials were conducted to establish if young primary specific pathogen free (SPF) pigs could be protected from Glasser's disease by vaccination. Three age groups of cesarean-derived isolator-reared gnotobiotic pigs were vaccinated twice at 4 and 6, 3 and 5, and 2 and 4 wk of age respectively with a formalin killed aluminum hydroxide adsorbed bacterin prepared from three strains of Haemophilus parasuis isolated from Ontario pigs affected with Glasser's disease. When challenged two weeks later with the homologous strains of virulent bacteria, all the vaccinated pigs remained healthy, while 17/18 nonvaccinated pigs became severely sick or died between three and seven days postchallenge. The one surviving nonimmunized pig was retarded in growth. All of the nonimmunized pigs had visible lesions of polyserositis, the most common being polyarthritis (14/18). Other lesions were fibrinous meningitis, pericarditis, pleurisy and/or peritonitis. Two of the pigs died with a septicemia. Haemophilus parasuis was isolated from 15/18 nonimmunized pigs, usually from several of the affected sites. The organisms were not isolated from the immunized pigs, nor from the surviving nonimmunized pig. Attempts to detect the presence of specific antibodies against the H. parasuis strains in the sera of the immunized or exposed pigs by the passive hemagglutination test or by enzyme linked immunoassay were unsuccessful. The results of this work indicate that primary SPF pigs can be protected from Glasser's disease by vaccination as early as 2 and 4 wk of age. The nature of this protective mechanism was not established in this study.

  13. Haemophilus influenzae Carriage in Children Attending French Day Care Centers: a Molecular Epidemiological Study

    Science.gov (United States)

    Dabernat, Henri; Plisson-Sauné, Marie-Anne; Delmas, Catherine; Séguy, Martine; Faucon, Gèneviéve; Pélissier, Roselyne; Carsenti, Hélène; Pradier, Christian; Roussel-Delvallez, Micheline; Leroy, Joël; Dupont, Marie-Jeanne; De Bels, Frédéric; Dellamonica, Pierre

    2003-01-01

    The nasopharyngeal Haemophilus influenzae flora of healthy children under the age of 3 years attending day care centers in three distinct French geographic areas was analyzed by sampling during two periods, spring 1999 (May and June) and fall 1999 (November and December). The average carrier rate among 1,683 children was 40.9%. The prevalence of capsulated H. influenzae carriers was 0.4% for type f and 0.6% for type e. No type b strains were found among these children, of whom 98.5% had received one or more doses of anti-Haemophilus b vaccine. Among the strains, 44.5% were TEM-type beta-lactamase producers and nine (1.3%) were beta-lactamase-negative ampicillin-resistant strains. Pulsed-field gel electrophoresis restriction patterns showed a large diversity with 366 SmaI patterns from 663 strains. Among the strains isolated during a given period, 33% were isolated simultaneously in more than one area. In each area, depending on the sampling period, 68 to 72% of the strains had new pulsotypes and persistence of 28 to 32% of the strains was noted. For the 297 beta-lactamase-producing strains, 194 patterns were found. The genomic diversity of these strains was comparable to that of the whole set of strains and does not suggest a clonal diffusion. Among the beta-lactamase-producing strains isolated in November and December, depending on the area, 66 to 73% had new pulsotypes with persistence of only 27 to 33% of the strains. In any given geographic area, colonization by H. influenzae appears to be a dynamic process involving a high degree of genomic heterogeneity among the noncapsulated colonizing strains. PMID:12682158

  14. Haemophilus influenzae Sepsis and Placental Abruption in an Unvaccinated Immigrant

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    Paul A. Calner

    2012-04-01

    Full Text Available Background: Haemophilus influenzae infections have declined dramatically in the United States sinceimplementation of the conjugate vaccine. However, in countries where widespread immunization is notroutine, H influenzae remains a significant cause of morbidity and mortality. We report a case of apreviously unvaccinated immigrant with confirmed H influenzae sepsis and placental abruption leadingto spontaneous abortion.Objectives: To alert emergency medicine practitioners that H influenzae should be recognized as amaternal, fetal, and neonatal pathogen. Clinicians should consider this diagnosis in immigrants presentingwith uncertain vaccination history, as H influenzae can cause significant morbidity and mortality.Case Presentation: A 36-year-old female was referred to our emergency department (ED with lowerabdominal pain with some vaginal spotting. The patient had an initial visit with normal laboratoryinvestigations and normal imaging results, with complete resolution of symptoms. The patient returned tothe ED with sudden onset of vaginal bleeding and abdominal pain. She presented at this time with sepsis,which progressed to septic shock, causing placental abruption and ultimately, spontaneous abortion. Thepatient was treated with pressors and antibiotics and was admitted to the medical intensive care unitwhere she received ampicillin, gentamycin, and clindamycin for suspected chorioamnionitis. The patient’sblood cultures came back positive after 1 day for H influenzae. The patient did well and was dischargedfrom the hospital 4 days later.Conclusion: Haemophilus influenzae should be recognized as a neonatal and maternal pathogen.Clinicians should consider this diagnosis in immigrants presenting with uncertain vaccination history,especially in pregnant females, as H influenzae can cause significant morbidity and mortality. [West JEmerg Med. 2012;13(1:133–135.

  15. Brain abscess caused by Haemophilus para phrophilus following a dental treatment in a girl. Report of a case

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    Vázquez Toledo María Eugenia

    2014-07-01

    Full Text Available We report the case of a six year old girl who developed three brain abscesses following a dental intervention (extraction of a tooth two weeks before. The etiologic agent was identified as Haemophilus paraprophilus, a gramnegative microorganism bacillus native mi- crobiota of the oropharynx nasopharynx and the gastrointestinal tract. 1 The patient was given ceftriaxone due to the sensitivity of the microorganism and metronidaole -because we couldn’t discard etiology by anaerobic- during six weeks. Surgical drainage of the abscesses was performed successfully. To date the patient has minimal neurologic sequelae. The importance of this case is that is the second report in the international literature of brain abscess secondary to Haemophilus paraprophilus in a pediatric patient and without associated heart disease.

  16. Loss of capsule expression by Haemophilus influenzae type b results in enhanced adherence to and invasion of human cells.

    OpenAIRE

    St Geme, J W; Falkow, S

    1991-01-01

    Haemophilus influenzae type b is a common cause of systemic bacterial disease in children, and the serotype b capsule is a major determinant of virulence. Nevertheless, as a consequence of the genetic configuration of the capb locus, type b strains become capsule deficient at a high frequency. To investigate the potential biological relevance of the predisposition to capsule loss, we compared the adherent and invasive abilities of several strains of H. influenzae type b and their isogenic cap...

  17. Haemophilus responses to nutritional immunity: epigenetic and morphological contribution to biofilm architecture, invasion, persistence and disease severity.

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    Blake R Szelestey

    Full Text Available In an effort to suppress microbial outgrowth, the host sequesters essential nutrients in a process termed nutritional immunity. However, inflammatory responses to bacterial insult can restore nutritional resources. Given that nutrient availability modulates virulence factor production and biofilm formation by other bacterial species, we hypothesized that fluctuations in heme-iron availability, particularly at privileged sites, would similarly influence Haemophilus biofilm formation and pathogenesis. Thus, we cultured Haemophilus through sequential heme-iron deplete and heme-iron replete media to determine the effect of transient depletion of internal stores of heme-iron on multiple pathogenic phenotypes. We observed that prior heme-iron restriction potentiates biofilm changes for at least 72 hours that include increased peak height and architectural complexity as compared to biofilms initiated from heme-iron replete bacteria, suggesting a mechanism for epigenetic responses that participate in the changes observed. Additionally, in a co-infection model for human otitis media, heme-iron restricted Haemophilus, although accounting for only 10% of the inoculum (90% heme-iron replete, represented up to 99% of the organisms recovered at 4 days. These data indicate that fluctuations in heme-iron availability promote a survival advantage during disease. Filamentation mediated by a SulA-related ortholog was required for optimal biofilm peak height and persistence during experimental otitis media. Moreover, severity of disease in response to heme-iron restricted Haemophilus was reduced as evidenced by lack of mucosal destruction, decreased erythema, hemorrhagic foci and vasodilatation. Transient restriction of heme-iron also promoted productive invasion events leading to the development of intracellular bacterial communities. Taken together, these data suggest that nutritional immunity, may, in fact, foster long-term phenotypic changes that better equip

  18. Difficult identification of Haemophilus influenzae, a typical cause of upper respiratory tract infections, in the microbiological diagnostic routine.

    Science.gov (United States)

    Hinz, Rebecca; Zautner, Andreas Erich; Hagen, Ralf Matthias; Frickmann, Hagen

    2015-03-01

    Haemophilus influenzae is a key pathogen of upper respiratory tract infections. Its reliable discrimination from nonpathogenic Haemophilus spp. is necessary because merely colonizing bacteria are frequent at primarily unsterile sites. Due to close phylogenetic relationship, it is not easy to discriminate H. influenzae from the colonizer Haemophilus haemolyticus. The frequency of H. haemolyticus isolations depends on factors like sampling site, patient condition, and geographic region. Biochemical discrimination has been shown to be nonreliable. Multiplex PCR including marker genes like sodC, fucK, and hpd or sequencing of the 16S rRNA gene, the P6 gene, or multilocus-sequence-typing is more promising. For the diagnostic routine, such techniques are too expensive and laborious. If available, matrix-assisted laser-desorption-ionization time-of-flight mass spectrometry is a routine-compatible option and should be used in the first line. However, the used database should contain well-defined reference spectra, and the spectral difference between H. influenzae and H. haemolyticus is small. Fluorescence in-situ hybridization is an option for less well-equipped laboratories, but the available protocol will not lead to conclusive results in all instances. It can be used as a second line approach. Occasional ambiguous results have to be resolved by alternative molecular methods like 16S rRNA gene sequencing.

  19. Development of an improved species specific PCR test for detection of Haemophilus parasuis.

    Science.gov (United States)

    Angen, Oystein; Oliveira, Simone; Ahrens, Peter; Svensmark, Birgitta; Leser, Thomas D

    2007-01-31

    A PCR test for identification of Haemophilus parasuis was optimized using the 16S rDNA sequences of the 15 serotype reference strains of H. parasuis. The test was evaluated on a collection of 218 Danish field isolates as well as on 81 representatives of 27 other species, including genetically affiliated species within Pasteurellaceae. In addition, DNA preparations from 56 H. parasuis isolates from North America were included. To obtain a test that was specific for H. parasuis, a multiplex PCR using 3 different primers was developed. The PCR test produced an amplicon of approximately 1090 bp only with representatives of H. parasuis. The test was further evaluated on 55 clinical samples from 16 Danish pigs suspected for being infected with H. parasuis, showing polyserositis or septicemia at autopsy as well as on 492 nasal swabs. The test was compared with the performance of a PCR test earlier published by Oliveira et al. [Oliveira, S., Galina, L., Pijoan, C., 2001. Development of a PCR test to diagnose Haemophilus parasuis infections. J. Vet. Diagn. Invest. 13, 495-501]. The sensitivity of the present PCR test was found to be slightly lower when applied on clinical samples from diseased pigs and 10-fold lower when tested on pure cultures of H. parasuis (5CFU and 0.5CFU/PCR reaction, respectively). Addition of 1.4 x 10(5) Escherichia coli to each PCR tube did not alter the sensitivity of the tests. No difference in sensitivity of the tests was observed when tested on purified DNA. On the other hand, the present PCR test was found to be 100% species specific for H. parasuis, in contrast to the PCR test of Oliveira et al., which also tested positive for strains belonging to A. indolicus, A. porcinus, and A. minor, species commonly occurring in the upper respiratory tract. However, when the PCR test of Oliveira et al. is used on samples from systemic locations the chances for false positive results are apparently low. The present PCR test represents a rapid and reliable

  20. Nontypeable Haemophilus influenzae induces sustained lung oxidative stress and protease expression.

    Directory of Open Access Journals (Sweden)

    Paul T King

    Full Text Available Nontypeable Haemophilus influenzae (NTHi is a prevalent bacterium found in a variety of chronic respiratory diseases. The role of this bacterium in the pathogenesis of lung inflammation is not well defined. In this study we examined the effect of NTHi on two important lung inflammatory processes 1, oxidative stress and 2, protease expression. Bronchoalveolar macrophages were obtained from 121 human subjects, blood neutrophils from 15 subjects, and human-lung fibroblast and epithelial cell lines from 16 subjects. Cells were stimulated with NTHi to measure the effect on reactive oxygen species (ROS production and extracellular trap formation. We also measured the production of the oxidant, 3-nitrotyrosine (3-NT in the lungs of mice infected with this bacterium. NTHi induced widespread production of 3-NT in mouse lungs. This bacterium induced significantly increased ROS production in human fibroblasts, epithelial cells, macrophages and neutrophils; with the highest levels in the phagocytic cells. In human macrophages NTHi caused a sustained, extracellular production of ROS that increased over time. The production of ROS was associated with the formation of macrophage extracellular trap-like structures which co-expressed the protease metalloproteinase-12. The formation of the macrophage extracellular trap-like structures was markedly inhibited by the addition of DNase. In this study we have demonstrated that NTHi induces lung oxidative stress with macrophage extracellular trap formation and associated protease expression. DNase inhibited the formation of extracellular traps.

  1. The extended leader peptide of Haemophilus parasuis trimeric autotransporters conditions their protein expression in Escherichia coli.

    Science.gov (United States)

    Pina-Pedrero, Sonia; Olvera, Àlex; Bensaid, Albert

    2017-05-01

    Trimeric autotransporters are surface-exposed proteins of Gram-negative bacteria belonging to the type V secretion system. They are involved in virulence and are targets for vaccine and diagnostic tool development, so optimal systems for their expression and purification are required. In the present study, the impact of the extended leader peptide of the Haemophilus parasuis virulence-associated trimeric autotransporters (VtaA) in its production as recombinant proteins in Escherichia coli was evaluated. The 13 genes encoding the VtaA1 to VtaA13 passenger domains of the strain Nagasaki were cloned in the pASK-IBA33plus plasmid and expressed in E. coli. Recombinant protein production was higher for truncated forms in which the entire leader peptide was deleted, and the recombinant protein accumulated in the cytoplasm of the cells. The yield of protein production of the different VtaAs was size dependent, and reached maximal amount at 2-4 h post -induction. The optimization of these conditions allowed to scale-up the production to obtain enough recombinant protein to immunize large animals. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Development of interpretive criteria for tebipenem disk diffusion susceptibility testing with Staphylococcus spp. and Haemophilus influenzae.

    Science.gov (United States)

    Fujisaki, Momoko; Sadamoto, Shinya; Ikedo, Masanari; Totsuka, Kyoichi; Kaku, Mitsuo; Tateda, Kazuhiro; Hirakata, Yoichi; Yamaguchi, Keizo

    2011-02-01

    Disk diffusion susceptibility interpretive criteria for tebipenem against Staphylococcus spp. and Haemophilus influenzae were developed using the Clinical and Laboratory Standards Institute (CLSI) guidelines. Tebipenem was tested by disk diffusion and broth microdilution methods against 119 clinical isolates of Staphylococcus spp. and 102 clinical isolates of H. influenzae. The zone diameters of 5-, 10-, and 30-μg disks were compared with broth microdilution minimum inhibitory concentration (MIC) results by scattergram and regression analysis. When the MIC breakpoint of 1 μg/ml was applied to the scattergrams, the 10-μg disk showed good correlation between the zone diameters and the MIC values. The corresponding disk diffusion zone diameter breakpoints with the 10-μg disk for Staphylococcus spp. were ≧22 mm (MIC ≦1 μg/ml) for susceptible, 20-21 mm (MIC = 2 μg/ml) for intermediate, and ≦19 mm (MIC ≧4 μg/ml) for resistant. We also proposed the breakpoint zone diameter of H. influenzae: ≧22 mm (MIC ≦1 μg/ml) for susceptible. These criteria demonstrated that the categorical agreements between disk diffusion and broth microdilution methods for Staphylococcus spp. and H. influenzae were 95.0% and 99.0%, respectively. The discrepancy rates of these criteria were acceptable to the CLSI guidelines.

  3. Limited Interactions between Streptococcus Suis and Haemophilus Parasuis in In Vitro Co-Infection Studies.

    Science.gov (United States)

    Mathieu-Denoncourt, Annabelle; Letendre, Corinne; Auger, Jean-Philippe; Segura, Mariela; Aragon, Virginia; Lacouture, Sonia; Gottschalk, Marcelo

    2018-01-06

    Streptococcus suis and Haemophilus parasuis are normal inhabitants of the porcine upper respiratory tract but are also among the most frequent causes of disease in weaned piglets worldwide, causing inflammatory diseases such as septicemia, meningitis and pneumonia. Using an in vitro model of infection with tracheal epithelial cells or primary alveolar macrophages (PAMs), it was possible to determine the interaction between S. suis serotype 2 and H. parasuis strains with different level of virulence. Within H. parasuis strains, the low-virulence F9 strain showed higher adhesion levels to respiratory epithelial cells and greater association levels to PAMs than the high-virulence Nagasaki strain. Accordingly, the low-virulence F9 strain induced, in general, higher levels of pro-inflammatory cytokines than the virulent Nagasaki strain from both cell types. In general, S. suis adhesion levels to respiratory epithelial cells were similar to H. parasuis Nagasaki strain. Yet, S. suis strains induced a significantly lower level of pro-inflammatory cytokine expression from epithelial cells and PAMs than those observed with both H. parasuis strains. Finally, this study has shown that, overall and under the conditions used in the present study, S. suis and H. parasuis have limited in vitro interactions between them and use probably different host receptors, regardless to their level of virulence.

  4. Effects on endotoxin pathogenicity in pigs with acute septicemia of Haemophilus parasuis infection.

    Science.gov (United States)

    Amano, H; Shibata, M; Takahashi, K; Sasaki, Y

    1997-06-01

    Changes of endotoxin in plasma, and the response of the coagulation system and blood cells in septicemia of Haemophilus parasuis infection were examined by inoculation with H. parasuis in specific pathogen-free (SPF) pigs. Eight pigs were inoculated intratracheally with 10(5), 10(6) and 10(7) colony formation units (CFU) of the strain Nagasaki (serovar 5). All pigs died 28 to 42 hr after inoculation. Haematologically, severe leukopenia occurred 24 hr post inoculation (hpi) until death. Glucose concentration decreased from 24 hpi to death. In the coagulation system, decrease of platelet counts, prolongation of prothrombin time, activated partial thromboplastin time, and increase of fibrinogen-fibrin degradation products were observed in all inoculated pigs. Endotoxin was detected in the plasma of all the inoculated pigs from 16 hpi to death, and its concentration rose dramatically just before death. H. parasuis was re-isolated from the blood of all inoculated pigs from 16 hpi to death, and also from almost all organs and body fluids of the pigs. The pigs had microthrombi in the kidney, liver and lungs, and many also had pneumonia, meningitis and serositis. H. parasuis antigen was detected in the lesions by the immunoperoxidase technique. The results indicated that disseminated intravascular coagulation (DIC) and endotoxin shock involved aggravation of clinical signs and death on the pigs induced to septicemia of H. parasuis.

  5. Glässer's disease in piglets produced by intraperitoneal inoculation with Haemophilus parasuis.

    Science.gov (United States)

    Morozumi, T; Hiramune, T; Kobayashi, K

    1981-01-01

    Haemophilus parasuis was inoculated into the abdominal cavities of piglets. Its infective doses varied from 1.4 X 10(6) to 1.0 X 10(9) organisms. When inoculated with 1.0 X 10(9) or 1.6 X 10(8) organisms, piglets were affected with fibrinous polyserositis associated with arthritis and purulent meningitis. The three disorders were considered to be characteristic of Glässer's disease. Septicemia was also found in many of the infected piglets, some of which died within a few days after inoculation. No lesions were observed in piglets inoculated with 1.4 X 10(7) or 1.4 X 10(6) organisms. It was difficult to reisolate H.parasuis from lesions, especially those in the abdominal cavities of piglets killed on the 6th day after inoculation. Agglutinating and complement-fixing antibodies were present in the piglets with Glässer's syndrome examined on the 6th day after inoculation. Neither of them was detected in any piglet manifesting no clinical signs, except transient pyrexia.

  6. Limited Interactions between Streptococcus Suis and Haemophilus Parasuis in In Vitro Co-Infection Studies

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    Annabelle Mathieu-Denoncourt

    2018-01-01

    Full Text Available Streptococcus suis and Haemophilus parasuis are normal inhabitants of the porcine upper respiratory tract but are also among the most frequent causes of disease in weaned piglets worldwide, causing inflammatory diseases such as septicemia, meningitis and pneumonia. Using an in vitro model of infection with tracheal epithelial cells or primary alveolar macrophages (PAMs, it was possible to determine the interaction between S. suis serotype 2 and H. parasuis strains with different level of virulence. Within H. parasuis strains, the low-virulence F9 strain showed higher adhesion levels to respiratory epithelial cells and greater association levels to PAMs than the high-virulence Nagasaki strain. Accordingly, the low-virulence F9 strain induced, in general, higher levels of pro-inflammatory cytokines than the virulent Nagasaki strain from both cell types. In general, S. suis adhesion levels to respiratory epithelial cells were similar to H. parasuis Nagasaki strain. Yet, S. suis strains induced a significantly lower level of pro-inflammatory cytokine expression from epithelial cells and PAMs than those observed with both H. parasuis strains. Finally, this study has shown that, overall and under the conditions used in the present study, S. suis and H. parasuis have limited in vitro interactions between them and use probably different host receptors, regardless to their level of virulence.

  7. Structural basis for haem piracy from host haemopexin by Haemophilus influenzae.

    Science.gov (United States)

    Zambolin, Silvia; Clantin, Bernard; Chami, Mohamed; Hoos, Sylviane; Haouz, Ahmed; Villeret, Vincent; Delepelaire, Philippe

    2016-05-18

    Haemophilus influenzae is an obligate human commensal/pathogen that requires haem for survival and can acquire it from several host haemoproteins, including haemopexin. The haem transport system from haem-haemopexin consists of HxuC, a haem receptor, and the two-partner-secretion system HxuB/HxuA. HxuA, which is exposed at the cell surface, is strictly required for haem acquisition from haemopexin. HxuA forms complexes with haem-haemopexin, leading to haem release and its capture by HxuC. The key question is how HxuA liberates haem from haemopexin. Here, we solve crystal structures of HxuA alone, and HxuA in complex with the N-terminal domain of haemopexin. A rational basis for the release of haem from haem-haemopexin is derived from both in vivo and in vitro studies. HxuA acts as a wedge that destabilizes the two-domains structure of haemopexin with a mobile loop on HxuA that favours haem ejection by redirecting key residues in the haem-binding pocket of haemopexin.

  8. Sap transporter mediated import and subsequent degradation of antimicrobial peptides in Haemophilus.

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    Catherine L Shelton

    2011-11-01

    Full Text Available Antimicrobial peptides (AMPs contribute to host innate immune defense and are a critical component to control bacterial infection. Nontypeable Haemophilus influenzae (NTHI is a commensal inhabitant of the human nasopharyngeal mucosa, yet is commonly associated with opportunistic infections of the upper and lower respiratory tracts. An important aspect of NTHI virulence is the ability to avert bactericidal effects of host-derived antimicrobial peptides (AMPs. The Sap (sensitivity to antimicrobial peptides ABC transporter equips NTHI to resist AMPs, although the mechanism of this resistance has remained undefined. We previously determined that the periplasmic binding protein SapA bound AMPs and was required for NTHI virulence in vivo. We now demonstrate, by antibody-mediated neutralization of AMP in vivo, that SapA functions to directly counter AMP lethality during NTHI infection. We hypothesized that SapA would deliver AMPs to the Sap inner membrane complex for transport into the bacterial cytoplasm. We observed that AMPs localize to the bacterial cytoplasm of the parental NTHI strain and were susceptible to cytoplasmic peptidase activity. In striking contrast, AMPs accumulated in the periplasm of bacteria lacking a functional Sap permease complex. These data support a mechanism of Sap mediated import of AMPs, a novel strategy to reduce periplasmic and inner membrane accumulation of these host defense peptides.

  9. PnuC and the utilization of the nicotinamide riboside analog 3-aminopyridine in Haemophilus influenzae.

    Science.gov (United States)

    Sauer, Elizabeta; Merdanovic, Melisa; Mortimer, Anne Price; Bringmann, Gerhard; Reidl, Joachim

    2004-12-01

    The utilization pathway for the uptake of NAD and nicotinamide riboside was previously characterized for Haemophilus influenzae. We now report on the cellular location, topology, and substrate specificity of PnuC. pnuC of H. influenzae is only distantly related to pnuC of Escherichia coli and Salmonella enterica serovar Typhimurium. When E. coli PnuC was expressed in an H. influenzae pnuC mutant, it was able to take up only nicotinamide riboside and not nicotinamide mononucleotide. Therefore, we postulated that PnuC transporters in general possess specificity for nicotinamide riboside. Earlier studies showed that 3-aminopyridine derivatives (e.g., 3-aminopyridine adenine dinucleotide) are inhibitory for H. influenzae growth. By testing characterized strains with mutations in the NAD utilization pathway, we show that 3-aminopyridine riboside is inhibitory to H. influenzae and is taken up by the NAD-processing and nicotinamide riboside route. 3-Aminopyridine riboside is utilized effectively in a pnuC+ background. In addition, we demonstrate that 3-aminopyridine adenine dinucleotide resynthesis is produced by NadR. 3-Aminopyridine riboside-resistant H. influenzae isolates were characterized, and mutations in nadR could be detected. We also tested other species of the family Pasteurellaceae, Pasteurella multocida and Actinobacillus actinomycetemcomitans, and found that 3-aminopyridine riboside does not act as a growth inhibitor; hence, 3-aminopyridine riboside represents an anti-infective agent with a very narrow host range.

  10. The dppBCDF gene cluster of Haemophilus influenzae: Role in heme utilization

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    Morton Daniel J

    2009-08-01

    Full Text Available Abstract Background Haemophilus influenzae requires a porphyrin source for aerobic growth and possesses multiple mechanisms to obtain this essential nutrient. This porphyrin requirement may be satisfied by either heme alone, or protoporphyrin IX in the presence of an iron source. One protein involved in heme acquisition by H. influenzae is the periplasmic heme binding protein HbpA. HbpA exhibits significant homology to the dipeptide and heme binding protein DppA of Escherichia coli. DppA is a component of the DppABCDF peptide-heme permease of E. coli. H. influenzae homologs of dppBCDF are located in the genome at a point distant from hbpA. The object of this study was to investigate the potential role of the H. influenzae dppBCDF locus in heme utilization. Findings An insertional mutation in dppC was constructed and the impact of the mutation on the utilization of both free heme and various proteinaceous heme sources as well as utilization of protoporphyrin IX was determined in growth curve studies. The dppC insertion mutant strain was significantly impacted in utilization of all tested heme sources and protoporphyin IX. Complementation of the dppC mutation with an intact dppCBDF gene cluster in trans corrected the growth defects seen in the dppC mutant strain. Conclusion The dppCBDF gene cluster constitutes part of the periplasmic heme-acquisition systems of H. influenzae.

  11. Antisera Against Certain Conserved Surface-Exposed Peptides of Nontypeable Haemophilus influenzae Are Protective.

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    Paul W Whitby

    Full Text Available Nontypeable Haemophilus influenzae (NTHi cause significant disease, including otitis media in children, exacerbations of chronic obstructive pulmonary disease, and invasive disease in susceptible populations. No vaccine is currently available to prevent NTHi disease. The interactions of NTHi and the human host are primarily mediated by lipooligosaccharide and a complex array of surface-exposed proteins (SEPs that act as receptors, sensors and secretion systems. We hypothesized that certain SEPs are present in all NTHi strains and that a subset of these may be antibody accessible and represent protective epitopes. Initially we used 15 genomic sequences available in the GenBank database along with an additional 11 genomic sequences generated by ourselves to identify the core set of putative SEPs present in all strains. Using bioinformatics, 56 core SEPs were identified. Molecular modeling generated putative structures of the SEPs from which potential surface exposed regions were defined. Synthetic peptides corresponding to ten of these highly conserved surface-exposed regions were used to raise antisera in rats. These antisera were used to assess passive protection in the infant rat model of invasive NTHi infection. Five of the antisera were protective, thus demonstrating their in vivo antibody accessibility. These five peptide regions represent potential targets for peptide vaccine candidates to protect against NTHi infection.

  12. Evidence for a Bicarbonate “Escort” Site in Haemophilus influenzae β-Carbonic Anhydrase†, ‡

    Science.gov (United States)

    Rowlett, Roger S.; Hoffmann, Katherine M.; Failing, Hannah; Mysliwiec, Margaret M.; Samardzic, Dejan

    2010-01-01

    The Haemophilus influenzae β-carbonic anhydrase (HICA) allosteric site variants V47A and G41A were overexpressed and purified to homogeneity. These variants have kcat/Km values similar to wild-type enzyme, and exhibit a similar dramatic decrease in catalytic activity at pH values below 8.0. However, both HICA-G41A and -V47A were serendipitously found to bind sulfate ion or bicarbonate ion near pairs of Glu50 and Arg64 residues located on the dimerization interface. In the case of HICA-V47A, bicarbonate ions simultaneously bind to both the dimerization interface and the allosteric sites. For HICA-G41A, 2 of 12 chains in the asymmetric unit bind bicarbonate ion exclusively at the dimerization interface, while the remaining 10 chains bind bicarbonate ion exclusively at the allosteric site. We propose that the new anion binding site along the dimerization interface of HICA is an “escort” site that represents an intermediate along the ingress/egress route of bicarbonate ion to/from the allosteric binding site. The structural evidence for sulfate binding at the “escort” site suggests that the mechanism of sulfate activation of HICA is the result of sulfate ion competing for bicarbonate at the “escort” site, preventing passage of bicarbonate from bulk solution to its allosteric site. PMID:20359198

  13. Regulation of the vapBC-1 toxin-antitoxin locus in nontypeable Haemophilus influenzae.

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    Susan D Cline

    Full Text Available Nontypeable Haemophilus influenzae (NTHi are human-adapted commensal bacteria that can cause a number of chronic mucosal infections, including otitis media and bronchitis. One way for these organisms to survive antibiotic therapy and cause recurrent disease is to stop replicating, as most antimicrobials target essential biosynthetic pathways. Toxin-antitoxin (TA gene pairs have been shown to facilitate entry into a reversible bacteriostatic state. Characteristically, these operons encode a protein toxin and an antitoxin that associate following translation to form a nontoxic complex, which then binds to and regulates the cognate TA promoter. Under stressful conditions, the labile antitoxin is degraded and the complex disintegrates, freeing the stable toxin to facilitate growth arrest. How these events affected the regulation of the TA locus, as well as how the transcription of the operon was subsequently returned to its normal state upon resumption of growth, was not fully understood. Here we show that expression of the NTHi vapBC-1 TA locus is repressed by a complex of VapB-1 and VapC-1 under conditions favorable for growth, and activated by the global transactivator Factor for Inversion Stimulation (Fis upon nutrient upshift from stationary phase. Further, we demonstrate for the first time that the VapC-1 toxin alone can bind to its cognate TA locus control region and that the presence of VapB-1 directs the binding of the VapBC-1 complex in the transcriptional regulation of vapBC-1.

  14. Comparative transcriptional profiling of tildipirosin-resistant and sensitive Haemophilus parasuis.

    Science.gov (United States)

    Lei, Zhixin; Fu, Shulin; Yang, Bing; Liu, Qianying; Ahmed, Saeed; Xu, Lei; Xiong, Jincheng; Cao, Jiyue; Qiu, Yinsheng

    2017-08-08

    Numerous studies have been conducted to examine the molecular mechanism of Haemophilus parasuis resistance to antibiotic, but rarely to tildipirosin. In the current study, transcriptional profiling was applied to analyse the variation in gene expression of JS0135 and tildipirosin-resistant JS32. The growth curves showed that JS32 had a higher growth rate but fewer bacteria than JS0135. The cell membranes of JS32 and a resistant clinical isolate (HB32) were observed to be smoother than those of JS0135. From the comparative gene expression profile 349 up- and 113 downregulated genes were observed, covering 37 GO and 63 KEGG pathways which are involved in biological processes (11), cellular components (17), molecular function (9), cellular processes (1), environmental information processing (4), genetic information processing (9) and metabolism (49) affected in JS32. In addition, the relative overexpression of genes of the metabolism pathway (HAPS_RS09315, HAPS_RS09320), ribosomes (HAPS_RS07815) and ABC transporters (HAPS_RS10945) was detected, particularly the metabolism pathway, and verified with RT-qPCR. Collectively, the gene expression profile in connection with tildipirosin resistance factors revealed unique and highly resistant determinants of H. parasuis to macrolides that warrant further attention due to the significant threat of bacterial resistance.

  15. Molecular characterization of four Haemophilus influenzae serotype a strains isolated from patients in Quebec, Canada.

    Science.gov (United States)

    Sill, Michelle L; Zhou, Jianwei; Law, Dennis K S; Lorange, Manon; Ringuette, Louise; Bekal, Sadjia; Tsang, Raymond S W

    2007-10-01

    Four epidemiologically unrelated Haemophilus influenzae serotype a (Hia) strains from patients in Quebec, Canada, were characterized and found to represent 3 distinct groups. One isolate, found to be biotype I and sequence type (ST)-62 by multilocus sequence typing, was shown to possess the copper- and zinc-containing superoxide dismutase gene, sodC, and was suspected to belong to clonal division II. The other 3 isolates were classified as clonal division I based on the absence of the sodC gene. Among the 3 sodC-negative Hia strains, 2 were biotype II and had related STs (ST-23 and ST-403) and highly similar DNA fingerprints, similar to a group of previously described Hia isolates causing invasive disease in Manitoba, Canada. The remaining sodC-negative strain belonged to biotype I and ST-4 and shared no common allele with ST-23, ST-403, or ST-62. This isolate also possessed the IS1016-bexA partial deletion, which is often associated with increased virulence. Despite the small number of isolates used in this study, our finding of 3 distinct groups shows the existence of a potential genetic diversity not previously described for Hia. Whether this genetic diversity is related to the severity and epidemiology of Hia disease requires further studies.

  16. Antibiotic resistance of streptococcus pneumoniae and haemophilus influenzae isolated from respiratory tract specimens

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    Hikmet Eda Aliskan

    2016-06-01

    Full Text Available Purpose: Streptococcus pneumoniae and Haemophilus influenzae are two of the major pathogens in respiratory infections, treatment is usually started empirically. The aim of this study was to detect in vitro resistance rates of S. pneumoniae and H. influenzae strains isolated from different lower respiratory clinical samples to the antibotics which are used for therapy of infections due to these pathogens. Material and Methods: Seventy seven S.pneumoniae and 117 H.influenzae strains, isolated from patients were included in the study. S.pneumoniae isolates which gave an inhibition zone diameter of >20 mm for oxacillin were considered susceptible for penicilin. For the isolates which had an oxacillin zone diameter of 2 mg/l and 31.1 % were intermediately resistant to parenteral penicillin. Resistance rates to antibiotics were as follows: erythromycin 40 %, trimethoprim/sulphametoxazole (TMP/SMX 54.5 % and ofloxacin 6.4%. beta-lactamases were detected in 15.6% of the H.influenzae isolates by nitrocefin positivity. Conclusion: H.influenzae strains (8.6% were identified as beta-lactamase negative ampicillin resistant (BLNAR strains. Resistance rates for other antibiotics were as follows: ampicillin 28.6%, cefaclor 36.5% , cefuroxime 30.1%, clarithromycin 9.6%, cloramphenicol 7% and TMP-SMX 43.9%. [Cukurova Med J 2016; 41(2.000: 201-207

  17. Biofilm-specific extracellular matrix proteins of non-typeable Haemophilus influenzae

    Science.gov (United States)

    Wu, Siva; Baum, Marc M.; Kerwin, James; Guerrero-Given, Debbie; Webster, Simon; Schaudinn, Christoph; VanderVelde, David; Webster, Paul

    2014-01-01

    Non-typeable Haemophilus influenzae (NTHi), a human respiratory tract pathogen can form colony biofilms in vitro. Bacterial cells and the amorphous extracellular matrix (ECM) constituting the biofilm can be separated using sonication. The ECM from 24 hr and 96 hr NTHi biofilms contained polysaccharides and proteinaceous components as detected by NMR and FTIR spectroscopy. More conventional chemical assays on the biofilm ECM confirmed the presence of these components and also DNA. Proteomics revealed eighteen proteins present in biofilm ECM that were not detected in planktonic bacteria. One ECM protein was unique to 24 hr biofilms, two were found only in 96 hr biofilms, and fifteen were present in the ECM of both 24 hr and 96 hr NTHi biofilms. All proteins identified were either associated with bacterial membranes or were cytoplasmic proteins. Immunocytochemistry showed two of the identified proteins, a DNA-directed RNA polymerase and the outer membrane protein OMP P2, associated with bacteria and biofilm ECM. Identification of biofilm-specific proteins present in immature biofilms is an important step in understanding the in vitro process of NTHi biofilm formation. The presence of a cytoplasmic protein and a membrane protein in the biofilm ECM of immature NTHi biofilms suggests that bacterial cell lysis may be a feature of early biofilm formation. PMID:24942343

  18. Resistance of non-typeable Haemophilus influenzae biofilms is independent of biofilm size.

    Science.gov (United States)

    Reimche, Jennifer L; Kirse, Daniel J; Whigham, Amy S; Swords, W Edward

    2017-02-01

    The inflammatory middle ear disease known as otitis media can become chronic or recurrent in some cases due to failure of the antibiotic treatment to clear the bacterial etiological agent. Biofilms are known culprits of antibiotic-resistant infections; however, the mechanisms of resistance for non-typeable Haemophilus influenzae biofilms have not been completely elucidated. In this study, we utilized in vitro static biofilm assays to characterize clinical strain biofilms and addressed the hypothesis that biofilms with greater biomass and/or thickness would be more resistant to antimicrobial-mediated eradication than thinner and/or lower biomass biofilms. Consistent with previous studies, antibiotic concentrations required to eliminate biofilm bacteria tended to be drastically higher than concentrations required to kill planktonic bacteria. The size characterizations of the biofilms formed by the clinical isolates were compared to their minimum biofilm eradication concentrations for four antibiotics. This revealed no correlation between biofilm thickness or biomass and the ability to resist eradication by antibiotics. Therefore, we concluded that biofilm size does not play a role in antibiotic resistance, suggesting that reduction of antibiotic penetration may not be a significant mechanism for antibiotic resistance for this bacterial opportunist. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. Effect of Haemophilus influenzae polysaccharide outer membrane protein complex conjugate vaccine on macrophages.

    Science.gov (United States)

    Ambrosino, D M; Bolon, D; Collard, H; Van Etten, R; Kanchana, M V; Finberg, R W

    1992-12-15

    Haemophilus influenzae type b polysaccharide-conjugate vaccines elicit protective antibody responses in young infants. One of these conjugates, polysaccharide linked to outer membrane protein complex (PRP-OMPC), is produced by linking the capsular polysaccharide to an outer membrane protein complex derived from group B Neisseria meningitidis. The outer membrane protein complex contains T cell carrier epitopes that elicit T cell-dependent antibody responses. OMPC also has been shown to increase the antibody response to other proteins administered concurrently that are not covalently linked (i.e., acts as an adjuvant). In this study PRP-OMPC immunized mice demonstrated significant increases in spleen size as well as in splenocyte number as compared to saline controls (p MHC class II Ag. Thus PRP-OMPC vaccine resulted in T cell-independent splenomegaly with an increase number of macrophages. We propose that this unique property may confer increased immunogenicity to PRP-OMPC through macrophage activation and cytokine release. Furthermore, the effect on macrophages may explain the "adjuvant" capacity of OMPC.

  20. Biofilm Growth Increases Phosphorylcholine Content and Decreases Potency of Nontypeable Haemophilus influenzae Endotoxins

    Science.gov (United States)

    West-Barnette, Shayla; Rockel, Andrea; Swords, W. Edward

    2006-01-01

    Nontypeable Haemophilus influenzae (NTHI) is a common respiratory commensal and opportunistic pathogen. NTHI is normally contained within the airways by host innate defenses that include recognition of bacterial endotoxins by Toll-like receptor 4 (TLR4). NTHI produces lipooligosaccharide (LOS) endotoxins which lack polymeric O side chains and which may contain host glycolipids. We recently showed that NTHI biofilms contain variants with sialylated LOS glycoforms that are essential to biofilm formation. In this study, we show that NTHI forms biofilms on epithelial cell layers. Confocal analysis revealed that sialylated variants were distributed throughout the biofilm, while variants expressing phosphorylcholine (PCho) were found within the biofilm. Consistent with this observation, PCho content of LOS purified from NTHI biofilms was increased compared to LOS from planktonic cultures. Hypothesizing that the observed changes in endotoxin composition could affect bioactivity, we compared inflammatory responses to NTHI LOS purified from biofilm and planktonic cultures. Our results show that endotoxins from biofilms induced weaker host innate responses. While we observed a minimal effect of sialylation on LOS bioactivity, there was a significant decrease in bioactivity associated with PCho substitutions. We thus conclude that biofilm growth increases the proportion of PCho+ variants in an NTHI population, resulting in a net decrease in LOS bioactivity. Thus, in addition to their well-documented resistance phenotypes, our data show that biofilm communities of NTHI bacteria contain variants that evoke less potent host responses. PMID:16495557

  1. Identification and characterization of a heme periplasmic-binding protein in Haemophilus ducreyi.

    Science.gov (United States)

    St Denis, Melissa; Sonier, Brigitte; Robinson, Renée; Scott, Fraser W; Cameron, D William; Lee, B Craig

    2011-08-01

    Haemophilus ducreyi, a gram-negative and heme-dependent bacterium, is the causative agent of chancroid, a genital ulcer sexually transmitted infection. Heme acquisition in H. ducreyi proceeds via a receptor mediated process in which the initial event involves binding of hemoglobin and heme to their cognate outer membrane proteins, HgbA and TdhA, respectively. Following this specific interaction, the fate of the periplasmic deposited heme is unclear. Using protein expression profiling of the H. ducreyi periplasmic proteome, a periplasmic-binding protein, termed hHbp, was identified whose expression was enhanced under heme-limited conditions. The gene encoding this protein was situated in a locus displaying genetic characteristics of an ABC transporter. The purified protein bound heme in a dose-dependent and saturable manner and this binding was specifically competitively inhibited by heme. The hhbp gene functionally complemented an Escherichia coli heme uptake mutant. Expression of the heme periplasmic-binding protein was detected in a limited survey of H. ducreyi and H. influenzae clinical strains. These results indicate that the passage of heme into the cytoplasm of H. ducreyi involves a heme dedicated ABC transporter.

  2. Transcription of candidate virulence genes of Haemophilus ducreyi during infection of human volunteers.

    Science.gov (United States)

    Throm, R E; Spinola, S M

    2001-03-01

    Haemophilus ducreyi expresses several putative virulence factors in vitro. Isogenic mutant-to-parent comparisons have been performed in a human model of experimental infection to examine whether specific gene products are involved in pathogenesis. Several mutants (momp, ftpA, losB, lst, cdtC, and hhdB) were as virulent as the parent in the human model, suggesting that their gene products did not play a major role in pustule formation. However, we could not exclude the possibility that the gene of interest was not expressed during the initial stages of infection. Biopsies of pustules obtained from volunteers infected with H. ducreyi were subjected to reverse transcription-PCR. Transcripts corresponding to momp, ftpA, losB, lst, cdtB, and hhdA were expressed in vivo. In addition, transcripts for other putative virulence determinants such as ompA2, tdhA, lspA1, and lspA2 were detected in the biopsies. These results indicate that although several candidate virulence determinants are expressed during experimental infection, they do not have a major role in the initial stages of pathogenesis.

  3. A biphasic epigenetic switch controls immunoevasion, virulence and niche adaptation in non-typeable Haemophilus influenzae.

    Science.gov (United States)

    Atack, John M; Srikhanta, Yogitha N; Fox, Kate L; Jurcisek, Joseph A; Brockman, Kenneth L; Clark, Tyson A; Boitano, Matthew; Power, Peter M; Jen, Freda E-C; McEwan, Alastair G; Grimmond, Sean M; Smith, Arnold L; Barenkamp, Stephen J; Korlach, Jonas; Bakaletz, Lauren O; Jennings, Michael P

    2015-07-28

    Non-typeable Haemophilus influenzae contains an N(6)-adenine DNA-methyltransferase (ModA) that is subject to phase-variable expression (random ON/OFF switching). Five modA alleles, modA2, modA4, modA5, modA9 and modA10, account for over two-thirds of clinical otitis media isolates surveyed. Here, we use single molecule, real-time (SMRT) methylome analysis to identify the DNA-recognition motifs for all five of these modA alleles. Phase variation of these alleles regulates multiple proteins including vaccine candidates, and key virulence phenotypes such as antibiotic resistance (modA2, modA5, modA10), biofilm formation (modA2) and immunoevasion (modA4). Analyses of a modA2 strain in the chinchilla model of otitis media show a clear selection for ON switching of modA2 in the middle ear. Our results indicate that a biphasic epigenetic switch can control bacterial virulence, immunoevasion and niche adaptation in an animal model system.

  4. Oldenlandia diffusa Extract Inhibits Biofilm Formation by Haemophilus influenzae Clinical Isolates.

    Science.gov (United States)

    Wajima, Takeaki; Anzai, Yui; Yamada, Tetsuya; Ikoshi, Hideaki; Noguchi, Norihisa

    2016-01-01

    Oldenlandia diffusa has been empirically used as a therapeutic adjunct for the treatment of respiratory infections. To establish the basic evidence of its clinical usefulness, antimicrobial and biofilm inhibitory activities of an O. diffusa extract were examined against clinical isolates of Haemophilus influenzae, a major causative pathogen of respiratory and sensory organ infections. No significant growth inhibitory activity was observed during incubation for more than 6 h after the extract addition into a culture of H. influenzae. On the other hand, biofilm formation by H. influenzae, evaluated by a crystal violet method, was significantly and dose-dependently inhibited by the O. diffusa extract. Furthermore, the mRNA level of the biofilm-associated gene luxS of H. influenzae significantly decreased soon after the extract addition, and the suppressive effect continued for at least 2 h. At 2 h after the addition of the O. diffusa extract, the autoinducer in the culture supernatant was also significantly reduced by the O. diffusa extract in a dose-dependent manner. These results revealed that O. diffusa extract shows inhibitory activity against luxS-dependent biofilm formation but has no antimicrobial activity against planktonic cells of H. influenzae. Thus, O. diffusa extract might be useful as an adjunctive therapy for the treatment of respiratory infections caused by H. influenzae.

  5. Immunoglobulin deficiency in patients with Streptococcus pneumoniae or Haemophilus influenzae invasive infections.

    Science.gov (United States)

    Martinot, Martin; Oswald, Laetitia; Parisi, Elisabeth; Etienne, Elodie; Argy, Nicolas; Grawey, Isabelle; De Briel, Dominique; Zadeh, Mahsa Mohseni; Federici, Laure; Blaison, Gilles; Koebel, Christelle; Jaulhac, Benoit; Hansmann, Yves; Christmann, Daniel

    2014-02-01

    Immunoglobulin (Ig) deficiency is a well-known risk factor for Streptococcus pneumoniae or Haemophilus influenzae infections and noteworthy invasive diseases. However, the proportion of these deficiencies in cases of invasive disease is unknown. The objective of this study was to evaluate the rate of Ig deficiency in cases of invasive disease. A prospective study was conducted from January 2008 to October 2010 in two French hospitals. Measurement of Ig levels was carried out in patients hospitalized for invasive diseases. A total of 119 patients were enrolled in the study, with nine cases of H. influenzae and 110 cases of S. pneumoniae invasive disease. There were 18 cases of meningitis, 79 of invasive pneumonia, and 22 other invasive diseases. Forty-five patients (37.8%) had an Ig abnormality, 37 of whom had an Ig deficiency (20 IgG deficiencies (three common variable immunodeficiencies and two complete IgA deficiencies) and 14 secondary deficiencies, mainly lymphoproliferative disorders. All these deficiencies were either not known or not substituted. Humoral deficiency is frequent in patients with S. pneumoniae or H. influenzae invasive disease and Ig dosage should be proposed systematically after such infections. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. A biphasic epigenetic switch controls immunoevasion, virulence and niche adaptation in non-typeable Haemophilus influenzae

    Science.gov (United States)

    Atack, John M.; Srikhanta, Yogitha N.; Fox, Kate L.; Jurcisek, Joseph A.; Brockman, Kenneth L.; Clark, Tyson A.; Boitano, Matthew; Power, Peter M.; Jen, Freda E.-C.; McEwan, Alastair G.; Grimmond, Sean M.; Smith, Arnold L.; Barenkamp, Stephen J.; Korlach, Jonas; Bakaletz, Lauren O.; Jennings, Michael P.

    2015-01-01

    Non-typeable Haemophilus influenzae contains an N6-adenine DNA-methyltransferase (ModA) that is subject to phase-variable expression (random ON/OFF switching). Five modA alleles, modA2, modA4, modA5, modA9 and modA10, account for over two-thirds of clinical otitis media isolates surveyed. Here, we use single molecule, real-time (SMRT) methylome analysis to identify the DNA-recognition motifs for all five of these modA alleles. Phase variation of these alleles regulates multiple proteins including vaccine candidates, and key virulence phenotypes such as antibiotic resistance (modA2, modA5, modA10), biofilm formation (modA2) and immunoevasion (modA4). Analyses of a modA2 strain in the chinchilla model of otitis media show a clear selection for ON switching of modA2 in the middle ear. Our results indicate that a biphasic epigenetic switch can control bacterial virulence, immunoevasion and niche adaptation in an animal model system. PMID:26215614

  7. Clinical and molecular epidemiology of haemophilus influenzae causing invasive disease in adult patients.

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    Carmen Puig

    Full Text Available The epidemiology of invasive Haemophilus influenzae (Hi has changed since the introduction of the Hi type b (Hib vaccine. The aim of this study was to analyze the clinical and molecular epidemiology of Hi invasive disease in adults.Clinical data of the 82 patients with Hi invasive infections were analyzed. Antimicrobial susceptibility, serotyping, and genotyping were studied (2008-2013.Men accounted for 63.4% of patients (whose mean age was 64.3 years. The most frequent comorbidities were immunosuppressive therapy (34.1%, malignancy (31.7%, diabetes, and COPD (both 22%. The 30-day mortality rate was 20.7%. The majority of the strains (84.3% were nontypeable (NTHi and serotype f was the most prevalent serotype in the capsulated strains. The highest antimicrobial resistance was for cotrimoxazole (27.1% and ampicillin (14.3%. Twenty-three isolates (32.9% had amino acid changes in the PBP3 involved in resistance. Capsulated strains were clonal and belonged to clonal complexes 6 (serotype b, 124 (serotype f, and 18 (serotype e, whereas NTHi were genetically diverse.Invasive Hi disease occurred mainly in elderly and those with underlying conditions, and it was associated with a high mortality rate. NTHi were the most common cause of invasive disease and showed high genetic diversity.

  8. Clinical and Molecular Epidemiology of Haemophilus influenzae Causing Invasive Disease in Adult Patients

    Science.gov (United States)

    Puig, Carmen; Grau, Imma; Tubau, Fe; Calatayud, Laura; Pallares, Roman; Liñares, Josefina

    2014-01-01

    Objectives The epidemiology of invasive Haemophilus influenzae (Hi) has changed since the introduction of the Hi type b (Hib) vaccine. The aim of this study was to analyze the clinical and molecular epidemiology of Hi invasive disease in adults. Methods Clinical data of the 82 patients with Hi invasive infections were analyzed. Antimicrobial susceptibility, serotyping, and genotyping were studied (2008–2013). Results Men accounted for 63.4% of patients (whose mean age was 64.3 years). The most frequent comorbidities were immunosuppressive therapy (34.1%), malignancy (31.7%), diabetes, and COPD (both 22%). The 30-day mortality rate was 20.7%. The majority of the strains (84.3%) were nontypeable (NTHi) and serotype f was the most prevalent serotype in the capsulated strains. The highest antimicrobial resistance was for cotrimoxazole (27.1%) and ampicillin (14.3%). Twenty-three isolates (32.9%) had amino acid changes in the PBP3 involved in resistance. Capsulated strains were clonal and belonged to clonal complexes 6 (serotype b), 124 (serotype f), and 18 (serotype e), whereas NTHi were genetically diverse. Conclusions Invasive Hi disease occurred mainly in elderly and those with underlying conditions, and it was associated with a high mortality rate. NTHi were the most common cause of invasive disease and showed high genetic diversity. PMID:25379704

  9. Structural Analysis of Substrate, Reaction Intermediate, and Product Binding in Haemophilus influenzae Biotin Carboxylase.

    Science.gov (United States)

    Broussard, Tyler C; Pakhomova, Svetlana; Neau, David B; Bonnot, Ross; Waldrop, Grover L

    2015-06-23

    Acetyl-CoA carboxylase catalyzes the first and regulated step in fatty acid synthesis. In most Gram-negative and Gram-positive bacteria, the enzyme is composed of three proteins: biotin carboxylase, a biotin carboxyl carrier protein (BCCP), and carboxyltransferase. The reaction mechanism involves two half-reactions with biotin carboxylase catalyzing the ATP-dependent carboxylation of biotin-BCCP in the first reaction. In the second reaction, carboxyltransferase catalyzes the transfer of the carboxyl group from biotin-BCCP to acetyl-CoA to form malonyl-CoA. In this report, high-resolution crystal structures of biotin carboxylase from Haemophilus influenzae were determined with bicarbonate, the ATP analogue AMPPCP; the carboxyphosphate intermediate analogues, phosphonoacetamide and phosphonoformate; the products ADP and phosphate; and the carboxybiotin analogue N1'-methoxycarbonyl biotin methyl ester. The structures have a common theme in that bicarbonate, phosphate, and the methyl ester of the carboxyl group of N1'-methoxycarbonyl biotin methyl ester all bound in the same pocket in the active site of biotin carboxylase and as such utilize the same set of amino acids for binding. This finding suggests a catalytic mechanism for biotin carboxylase in which the binding pocket that binds tetrahedral phosphate also accommodates and stabilizes a tetrahedral dianionic transition state resulting from direct transfer of CO₂ from the carboxyphosphate intermediate to biotin.

  10. Necrotizing fasciitis caused by Haemophilus influenzae type b in a patient with rectal cancer treated with combined bevacizumab and chemotherapy: a case report.

    Science.gov (United States)

    Ugai, Tomotaka; Norizuki, Masataro; Mikawa, Takahiro; Ohji, Goh; Yaegashi, Makito

    2014-04-12

    Recently, necrotizing fasciitis has been reported in patients treated with bevacizumab, usually secondary to wound healing complications, gastrointestinal perforations, or fistula formation. The risk of invasive Haemophilus influenzae type b infection is significantly increased in immunocompromised hosts. However, necrotizing fasciitis due to Haemophilus influenzae type b in a patient treated with combined bevacizumab and chemotherapy has not been previously reported. A 59-year-old woman was admitted to the intensive care unit after sudden onset of fever, chills, and right thigh pain. She received chemotherapy with fluorouracil, irinotecan, and bevacizumab for colon cancer 10 days prior to admission. The advancing erythematous margin and her worsening clinical condition prompted us to suspect necrotizing fasciitis and consult the orthopedics department for a fascia biopsy and debridement. Surgical exploration revealed a murky dishwater-colored pus exudate from the incision site and the lack of a shiny appearance of the fascia that also suggested necrotizing fasciitis. After 2 days, the final results of the blood and exudate cultures confirmed the presence of Haemophilus influenzae type b. A diagnosis of necrotizing fasciitis due to Haemophilus influenzae type b was made. The patient required recurrent surgical debridement and drainage, but she recovered from the septic shock. We report a case of necrotizing fasciitis due to Haemophilus influenzae type b in a patient without injury and with rectal cancer treated with combined bevacizumab and chemotherapy. Physicians should consider invasive Haemophilus influenzae type b disease in the presence of necrotizing fasciitis in patients treated with this combined treatment modality.

  11. Molecular Serotype-Specific Identification of Non-type b Haemophilus influenzae by Loop-Mediated Isothermal Amplification

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    Chika Takano

    2017-10-01

    Full Text Available Over the past four decades, the incidence of meningitis caused by Haemophilus influenzae in children has decreased due to widespread vaccination against H. influenzae type b (Hib. The incidence of invasive diseases due to H. influenzae types not included in the vaccines, however, has increased. At present, there are a limited number of diagnostics available to detect non-type b H. influenzae. To address this issue, we developed a rapid, simple, and cost-effective method for detecting serotypes of H. influenzae. We designed LAMP primer sets based on published sequences for H. influenzae capsular types a, c, d, e, and f. The assay was evaluated to determine test reactivity, specificity, and sensitivity. To support its use in patients with suspected meningitis, we evaluated the detection limit of the non-Hib serotype specific LAMP assay using bacterial genomic DNA-spiked cerebrospinal fluid (CSF specimens. The reactivity and specificity of the LAMP assays were confirmed using six serotypes and non-typeable H. influenzae strains, plus eight strains of other Haemophilus species and non-Haemophilus genera. The detection limits of the LAMP assay for capsular types a, c, d, e, and f were 102, 102, 102, 103, and 10 copies per reaction, while those of the PCR assay were 104, 104, 103, 103, and 104 genome copies per reaction, respectively. Using DNA-spiked CSF specimens, the detection limit of the LAMP assay was equivalent to that using purified DNA as the template. However, the detection limit of the PCR was reduced from 103 to 104 genome copies per reaction for serotype d and from 103 to 105 genome copies per reaction for serotype e. To the best of our knowledge, this is the first report of a serotype-specific identification assay for H. influenzae using the LAMP method. Our results suggest the potential of LAMP methods for patients with suspected meningitis in resource-limited laboratories or public health surveillance systems.

  12. hgpB, a Gene Encoding a Second Haemophilus influenzae Hemoglobin- and Hemoglobin-Haptoglobin-Binding Protein

    OpenAIRE

    Ren, Zhen; Jin, Hongfan; Morton, Daniel J.; Stull, Terrence L.

    1998-01-01

    Haemophilus influenzae requires heme for growth and can utilize both hemoglobin and hemoglobin-haptoglobin as heme sources. We previously identified a hemoglobin- and hemoglobin-haptoglobin-binding protein, HgpA, in H. influenzae HI689. Mutation of hgpA did not affect binding or utilization of either heme source. The hgpA mutant exhibited loss of a 120-kDa protein and increased expression of a 115-kDa protein. These data suggested that at least one other gene product is involved in binding of...

  13. Haemophilus ducreyi Cutaneous Ulcer Strains Are Nearly Identical to Class I Genital Ulcer Strains.

    Science.gov (United States)

    Gangaiah, Dharanesh; Webb, Kristen M; Humphreys, Tricia L; Fortney, Kate R; Toh, Evelyn; Tai, Albert; Katz, Samantha S; Pillay, Allan; Chen, Cheng-Yen; Roberts, Sally A; Munson, Robert S; Spinola, Stanley M

    2015-01-01

    Although cutaneous ulcers (CU) in the tropics is frequently attributed to Treponema pallidum subspecies pertenue, the causative agent of yaws, Haemophilus ducreyi has emerged as a major cause of CU in yaws-endemic regions of the South Pacific islands and Africa. H. ducreyi is generally susceptible to macrolides, but CU strains persist after mass drug administration of azithromycin for yaws or trachoma. H. ducreyi also causes genital ulcers (GU) and was thought to be exclusively transmitted by microabrasions that occur during sex. In human volunteers, the GU strain 35000HP does not infect intact skin; wounds are required to initiate infection. These data led to several questions: Are CU strains a new variant of H. ducreyi or did they evolve from GU strains? Do CU strains contain additional genes that could allow them to infect intact skin? Are CU strains susceptible to azithromycin? To address these questions, we performed whole-genome sequencing and antibiotic susceptibility testing of 5 CU strains obtained from Samoa and Vanuatu and 9 archived class I and class II GU strains. Except for single nucleotide polymorphisms, the CU strains were genetically almost identical to the class I strain 35000HP and had no additional genetic content. Phylogenetic analysis showed that class I and class II strains formed two separate clusters and CU strains evolved from class I strains. Class I strains diverged from class II strains ~1.95 million years ago (mya) and CU strains diverged from the class I strain 35000HP ~0.18 mya. CU and GU strains evolved under similar selection pressures. Like 35000HP, the CU strains were highly susceptible to antibiotics, including azithromycin. These data suggest that CU strains are derivatives of class I strains that were not recognized until recently. These findings require confirmation by analysis of CU strains from other regions.

  14. Haemophilus ducreyi Cutaneous Ulcer Strains Are Nearly Identical to Class I Genital Ulcer Strains.

    Directory of Open Access Journals (Sweden)

    Dharanesh Gangaiah

    Full Text Available Although cutaneous ulcers (CU in the tropics is frequently attributed to Treponema pallidum subspecies pertenue, the causative agent of yaws, Haemophilus ducreyi has emerged as a major cause of CU in yaws-endemic regions of the South Pacific islands and Africa. H. ducreyi is generally susceptible to macrolides, but CU strains persist after mass drug administration of azithromycin for yaws or trachoma. H. ducreyi also causes genital ulcers (GU and was thought to be exclusively transmitted by microabrasions that occur during sex. In human volunteers, the GU strain 35000HP does not infect intact skin; wounds are required to initiate infection. These data led to several questions: Are CU strains a new variant of H. ducreyi or did they evolve from GU strains? Do CU strains contain additional genes that could allow them to infect intact skin? Are CU strains susceptible to azithromycin?To address these questions, we performed whole-genome sequencing and antibiotic susceptibility testing of 5 CU strains obtained from Samoa and Vanuatu and 9 archived class I and class II GU strains. Except for single nucleotide polymorphisms, the CU strains were genetically almost identical to the class I strain 35000HP and had no additional genetic content. Phylogenetic analysis showed that class I and class II strains formed two separate clusters and CU strains evolved from class I strains. Class I strains diverged from class II strains ~1.95 million years ago (mya and CU strains diverged from the class I strain 35000HP ~0.18 mya. CU and GU strains evolved under similar selection pressures. Like 35000HP, the CU strains were highly susceptible to antibiotics, including azithromycin.These data suggest that CU strains are derivatives of class I strains that were not recognized until recently. These findings require confirmation by analysis of CU strains from other regions.

  15. Accelerating policy decisions to adopt haemophilus influenzae type B vaccine: a global, multivariable analysis.

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    Jessica C Shearer

    2010-03-01

    Full Text Available Adoption of new and underutilized vaccines by national immunization programs is an essential step towards reducing child mortality. Policy decisions to adopt new vaccines in high mortality countries often lag behind decisions in high-income countries. Using the case of Haemophilus influenzae type b (Hib vaccine, this paper endeavors to explain these delays through the analysis of country-level economic, epidemiological, programmatic and policy-related factors, as well as the role of the Global Alliance for Vaccines and Immunisation (GAVI Alliance.Data for 147 countries from 1990 to 2007 were analyzed in accelerated failure time models to identify factors that are associated with the time to decision to adopt Hib vaccine. In multivariable models that control for Gross National Income, region, and burden of Hib disease, the receipt of GAVI support speeded the time to decision by a factor of 0.37 (95% CI 0.18-0.76, or 63%. The presence of two or more neighboring country adopters accelerated decisions to adopt by a factor of 0.50 (95% CI 0.33-0.75. For each 1% increase in vaccine price, decisions to adopt are delayed by a factor of 1.02 (95% CI 1.00-1.04. Global recommendations and local studies were not associated with time to decision.This study substantiates previous findings related to vaccine price and presents new evidence to suggest that GAVI eligibility is associated with accelerated decisions to adopt Hib vaccine. The influence of neighboring country decisions was also highly significant, suggesting that approaches to support the adoption of new vaccines should consider supply- and demand-side factors.

  16. Towards a Standardized Method for Broth Microdilution Susceptibility Testing of Haemophilus parasuis.

    Science.gov (United States)

    Prüller, Sandra; Turni, Conny; Blackall, Patrick J; Beyerbach, Martin; Klein, Günter; Kreienbrock, Lothar; Strutzberg-Minder, Katrin; Kaspar, Heike; Meemken, Diana; Kehrenberg, Corinna

    2017-01-01

    Currently, there is no agreed method available for broth microdilution susceptibility testing of Haemophilus parasuis, one of the most important bacterial pathogens in pig production. Therefore, the aim of this study was to develop a method that could be easily performed by diagnostic laboratories and that appears suitable for a harmonized susceptibility testing. Growth determinations using one type strain and three field isolates revealed no visible growth of H. parasuis in media which have proven to be suitable for susceptibility testing of fastidious organisms. Therefore, a new medium, cation-adjusted Mueller-Hinton broth (CAMHB) plus NADH and sterile filtered heat-inactivated chicken serum, was developed. The reproducibility of MICs obtained in this medium was evaluated and statistically analyzed, considering a model with two different variables (precondition of five identical MICs and MIC mode accepting a deviation of ±1 dilution step, respectively). No significant differences for both variables were seen between two time points investigated and between results obtained with the recently proposed test medium broth (TMB). Nearly all MICs of quality control strains were in the acceptable range. Subsequently, 47 H. parasuis isolates representing 13 serovars were tested with the newly developed medium and TMB. Statistical analysis of all isolates and 15 antimicrobial agents and antimicrobial combinations showed no significant difference between MICs obtained in supplemented CAMHB and TMB. Because of a simplified implementation in routine diagnostic and a lower chance of interference between medium components and antimicrobial agents, supplemented CAMHB is recommended with an incubation time of 24 h. Copyright © 2016 American Society for Microbiology.

  17. A robust PCR for the differentiation of potential virulent strains of Haemophilus parasuis.

    Science.gov (United States)

    Galofré-Milà, N; Correa-Fiz, F; Lacouture, S; Gottschalk, M; Strutzberg-Minder, K; Bensaid, A; Pina-Pedrero, S; Aragon, V

    2017-05-08

    Haemophilus parasuis is the etiological agent of Glässer's disease in swine. H. parasuis comprises strains with heterogeneous virulence capacity, from non-virulent to highly virulent. Determination of the pathogenic potential of the strains is important for diagnosis and disease control. The virulence-associated trimeric autotransporters (vtaA) genes have been used to predict H. parasuis virulence by PCR amplification of their translocator domains. Here, we report a new and improved PCR designed to detect a different domain of the vtaA genes, the leader sequence (LS) as a diagnostic tool to predict virulence. A collection of 360 H. parasuis strains was tested by PCR with LS specific primers. Results of the PCR were compared with the clinical origin of the strains and, for a subset of strains, with their phagocytosis and serum resistance using a Chi-square test. LS-PCR was specific to H. parasuis, and allowed the differential detection of the leader sequences found in clinical and non-clinical isolates. Significant correlation was observed between the results of the LS-PCR and the clinical origin (organ of isolation) of the strains, as well as with their phagocytosis and serum susceptibility, indicating that this PCR is a good predictor of the virulence of the strains. In addition, this new PCR showed a full correlation with the previously validated PCR based on the translocator domain. LS-PCR could be performed in a wide range of annealing temperatures without losing specificity. This newly described PCR based on the leader sequence of the vtaA genes, LS-PCR, is a robust test for the prediction of the virulence potential of H. parasuis strains.

  18. Economic Evaluation and Budget Impact Analysis of Vaccination against Haemophilus influenzae Type b Infection in Thailand

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    Surachai Kotirum

    2017-11-01

    Full Text Available Current study aimed to estimate clinical and economic outcomes of providing the Haemophilus influenzae type b (Hib vaccination as a national vaccine immunization program in Thailand. A decision tree combined with Markov model was developed to simulate relevant costs and health outcomes covering lifetime horizon in societal and health care payer perspectives. This analysis considered children aged under 5 years old whom preventive vaccine of Hib infection are indicated. Two combined Hib vaccination schedules were considered: three-dose series (3 + 0 and three-dose series plus a booster does (3 + 1 compared with no vaccination. Budget impact analysis was also performed under Thai government perspective. The outcomes were reported as Hib-infected cases averted and incremental cost-effectiveness ratios (ICERs in 2014 Thai baht (THB ($ per quality-adjusted life year (QALY gained. In base-case scenario, the model estimates that 3,960 infected cases, 59 disability cases, and 97 deaths can be prevented by national Hib vaccination program. The ICER for 3 + 0 schedule was THB 1,099 ($34 per QALY gained under societal perspective. The model was sensitive to pneumonia incidence among aged under 5 years old and direct non-medical care cost per episode of Hib pneumonia. Hib vaccination is very cost-effective in the Thai context. The budget impact analysis showed that Thai government needed to invest an additional budget of 110 ($3.4 million to implement Hib vaccination program. Policy makers should consider our findings for adopting this vaccine into national immunization program.

  19. No evidence of increasing Haemophilus influenzae non-b infection in Australian Aboriginal children

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    Robert I. Menzies

    2013-08-01

    Full Text Available Background. High, or increasing, rates of invasive Haemophilus influenzae (Hi type a disease have been reported from North American native children from circumpolar regions, raising the question of serotype replacement being driven by vaccination against Hi type b (Hib. Indigenous Australians from remote areas had high rates of invasive Hib disease in the past, comparable to those in North American Indigenous populations. Objective. Evaluate incidence rates of invasive Hi (overall and by serotype in Indigenous Australian children over time. Design. Descriptive study of Hi incidence rates by serotype, in the Northern Territory (NT and South Australia (SA from 2001 to 2011. Comparison of NT data with a study that was conducted in the NT in 1985–1988, before Hib vaccine was introduced. Results. The average annual rate of invasive Hi type a (Hia disease in Indigenous children aged <5 years was 11/100,000 population. Although the incidence of Hi infection in Indigenous children in 2001–2003 was lower than during 2004–2011, this may be due to changes in surveillance. No other trend over time in individual serotypes or total invasive Hi disease, in Indigenous or non-Indigenous people, was identified. Compared to 1985–1988, rates in 2001–2011 were lower in all serotype groupings, by 98% for Hib, 75% for Hia, 79% for other serotypes and 67% for non-typeable Hi. Conclusions. There is no evidence of increases in invasive disease due to Hia, other specific non-b types, or non-typeable Hi in Australian Indigenous children. These data suggest that the increase in Hia some time after the introduction of Hib vaccine, as seen in the North American Arctic Region, is not common to all populations with high pre-vaccine rates of invasive Hib disease. However, small case numbers and the lack of molecular subtyping and PCR confirmation of pre-vaccine results complicate comparisons with North American epidemiology.

  20. The Epidemiologic and Pharmacodynamic Cutoff Values of Tilmicosin against Haemophilus parasuis

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    Haihong eHao

    2016-03-01

    Full Text Available The aim of this study was to establish antimicrobial susceptibility breakpoints for tilmicosin against Haemophilus parasuis, which is an important pathogen of respiratory tract infections. The minimum inhibitory concentrations (MICs of 103 H. parasuis isolates were determined by the agar dilution method. The wild-type (WT distribution and epidemiologic cutoff value (ECV were evaluated by statistical analysis. The new bronchoaveolar lavage (BAL was used to establish intrapulmonary pharmacokinetic (PK model in swine. The pharmacokinetic (PK parameters of tilmicosin, both in pulmonary epithelial lining fluid (PELF and in plasma, were determined using high performance liquid chromatography (HPLC method and WinNonlin software. The pharmacodynamic cutoff (COPD was calculated using Monte Carlo simulation. Our results showed that 100% of WT isolates were covered when the ECV was set at 16μg/mL. The tilmicosin had concentration-dependent activity against H. parasuis. The PK data indicated that tilmicosin concentrations in PELF was rapidly increased to high levels at 4 hours and kept stable until 48 hours after drug administration, while the tilmicosin concentration in plasma reached maximum levels at 4 hours and continued to decrease during 4-72 hours. Using Monte Carlo simulation, COPD was defined as 1 μg/mL. Conclusively, the ECV and COPD of tilmicosin against H. parasuis were established for the first time based on the MIC distribution and PK-PD analysis in the target tissue, respectively. These values are of great importance for detection of tilmicosin-resistant H. parasuis and for effective treatment of clinical intrapulmonary infection caused by H. parasuis.

  1. Recognition of Nucleoside Monophosphate Substrates by Haemophilus influenzae Class C Acid Phosphatase

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    Singh, Harkewal; Schuermann, Jonathan P.; Reilly, Thomas J.; Calcutt, Michael J.; Tanner, John J. (Cornell); (UMC)

    2010-12-08

    The e (P4) phosphatase from Haemophilus influenzae functions in a vestigial NAD{sup +} utilization pathway by dephosphorylating nicotinamide mononucleotide to nicotinamide riboside. P4 is also the prototype of class C acid phosphatases (CCAPs), which are nonspecific 5{prime},3{prime}-nucleotidases localized to the bacterial outer membrane. To understand substrate recognition by P4 and other class C phosphatases, we have determined the crystal structures of a substrate-trapping mutant P4 enzyme complexed with nicotinamide mononucleotide, 5{prime}-AMP, 3{prime}-AMP, and 2{prime}-AMP. The structures reveal an anchor-shaped substrate-binding cavity comprising a conserved hydrophobic box that clamps the nucleotide base, a buried phosphoryl binding site, and three solvent-filled pockets that contact the ribose and the hydrogen-bonding edge of the base. The span between the hydrophobic box and the phosphoryl site is optimal for recognizing nucleoside monophosphates, explaining the general preference for this class of substrate. The base makes no hydrogen bonds with the enzyme, consistent with an observed lack of base specificity. Two solvent-filled pockets flanking the ribose are key to the dual recognition of 5{prime}-nucleotides and 3{prime}-nucleotides. These pockets minimize the enzyme's direct interactions with the ribose and provide sufficient space to accommodate 5{prime} substrates in an anti conformation and 3{prime} substrates in a syn conformation. Finally, the structures suggest that class B acid phosphatases and CCAPs share a common strategy for nucleotide recognition.

  2. Haemophilus influenzae OxyR: characterization of its regulation, regulon and role in fitness.

    Directory of Open Access Journals (Sweden)

    Paul W Whitby

    Full Text Available To prevent damage by reactive oxygen species, many bacteria have evolved rapid detection and response systems, including the OxyR regulon. The OxyR system detects reactive oxygen and coordinates the expression of numerous defensive antioxidants. In many bacterial species the coordinated OxyR-regulated response is crucial for in vivo survival. Regulation of the OxyR regulon of Haemophilus influenzae was examined in vitro, and significant variation in the regulated genes of the OxyR regulon among strains of H. influenzae was observed. Quantitative PCR studies demonstrated a role for the OxyR-regulated peroxiredoxin/glutaredoxin as a mediator of the OxyR response, and also indicated OxyR self-regulation through a negative feedback loop. Analysis of transcript levels in H. influenzae samples derived from an animal model of otitis media demonstrated that the members of the OxyR regulon were actively upregulated within the chinchilla middle ear. H. influenzae mutants lacking the oxyR gene exhibited increased sensitivity to challenge with various peroxides. The impact of mutations in oxyR was assessed in various animal models of H. influenzae disease. In paired comparisons with the corresponding wild-type strains, the oxyR mutants were unaffected in both the chinchilla model of otitis media and an infant model of bacteremia. However, in weanling rats the oxyR mutant was significantly impaired compared to the wild-type strain. In contrast, in all three animal models when infected with a mixture of equal numbers of both wild-type and mutant strains the mutant strain was significantly out competed by the wild-type strain. These findings clearly establish a crucial role for OxyR in bacterial fitness.

  3. HPAEC-PAD quantification of Haemophilus influenzae type b polysaccharide in upstream and downstream samples.

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    van der Put, Robert M F; de Haan, Alex; van den IJssel, Jan G M; Hamidi, Ahd; Beurret, Michel

    2015-11-27

    Due to the rapidly increasing introduction of Haemophilus influenzae type b (Hib) and other conjugate vaccines worldwide during the last decade, reliable and robust analytical methods are needed for the quantitative monitoring of intermediate samples generated during fermentation (upstream processing, USP) and purification (downstream processing, DSP) of polysaccharide vaccine components. This study describes the quantitative characterization of in-process control (IPC) samples generated during the fermentation and purification of the capsular polysaccharide (CPS), polyribosyl-ribitol-phosphate (PRP), derived from Hib. Reliable quantitative methods are necessary for all stages of production; otherwise accurate process monitoring and validation is not possible. Prior to the availability of high performance anion exchange chromatography methods, this polysaccharide was predominantly quantified either with immunochemical methods, or with the colorimetric orcinol method, which shows interference from fermentation medium components and reagents used during purification. Next to an improved high performance anion exchange chromatography-pulsed amperometric detection (HPAEC-PAD) method, using a modified gradient elution, both the orcinol assay and high performance size exclusion chromatography (HPSEC) analyses were evaluated. For DSP samples, it was found that the correlation between the results obtained by HPAEC-PAD specific quantification of the PRP monomeric repeat unit released by alkaline hydrolysis, and those from the orcinol method was high (R(2)=0.8762), and that it was lower between HPAEC-PAD and HPSEC results. Additionally, HPSEC analysis of USP samples yielded surprisingly comparable results to those obtained by HPAEC-PAD. In the early part of the fermentation, medium components interfered with the different types of analysis, but quantitative HPSEC data could still be obtained, although lacking the specificity of the HPAEC-PAD method. Thus, the HPAEC

  4. Development of a Multiplex PCR Assay for Rapid Molecular Serotyping of Haemophilus parasuis

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    Peters, Sarah E.; Wang, Jinhong; Hernandez-Garcia, Juan; Weinert, Lucy A.; Luan, Shi-Lu; Chaudhuri, Roy R.; Angen, Øystein; Aragon, Virginia; Williamson, Susanna M.; Langford, Paul R.; Rycroft, Andrew N.; Wren, Brendan W.; Maskell, Duncan J.; Tucker, Alexander W.

    2015-01-01

    Haemophilus parasuis causes Glässer's disease and pneumonia in pigs. Indirect hemagglutination (IHA) is typically used to serotype this bacterium, distinguishing 15 serovars with some nontypeable isolates. The capsule loci of the 15 reference strains have been annotated, and significant genetic variation was identified between serovars, with the exception of serovars 5 and 12. A capsule locus and in silico serovar were identified for all but two nontypeable isolates in our collection of >200 isolates. Here, we describe the development of a multiplex PCR, based on variation within the capsule loci of the 15 serovars of H. parasuis, for rapid molecular serotyping. The multiplex PCR (mPCR) distinguished between all previously described serovars except 5 and 12, which were detected by the same pair of primers. The detection limit of the mPCR was 4.29 × 105 ng/μl bacterial genomic DNA, and high specificity was indicated by the absence of reactivity against closely related commensal Pasteurellaceae and other bacterial pathogens of pigs. A subset of 150 isolates from a previously sequenced H. parasuis collection was used to validate the mPCR with 100% accuracy compared to the in silico results. In addition, the two in silico-nontypeable isolates were typeable using the mPCR. A further 84 isolates were analyzed by mPCR and compared to the IHA serotyping results with 90% concordance (excluding those that were nontypeable by IHA). The mPCR was faster, more sensitive, and more specific than IHA, enabling the differentiation of 14 of the 15 serovars of H. parasuis. PMID:26424843

  5. Academic achievement in children ten to 12 years after Haemophilus influenzae meningitis.

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    Feldman, H M; Michaels, R H

    1988-03-01

    Academic achievement by 23 children 10 to 12 years after treatment of Haemophilus influenzae meningitis was assessed using individually administered standardized tests, review of school transcripts, and parent and teacher questionnaires. The children's performance was compared with (1) their own performance in a previous study 6 to 8 years after the illness; (2) the performance of 23 similarly aged siblings in the previous study, a comparison which served to age match subjects and sibling controls; and (3) the performance of 11 of those similarly aged siblings retested in the current study. Subjects scored in the average range on all measures. Scores were comparable to results 4 years previous in four of six academic measures, with minor deterioration in reading single words and decoding nonsense words. There were no differences between subjects in the current study and control subjects from the previous study, except in decoding nonsense words, and no differences between subjects and control subjects in the current study, except in paragraph reading accuracy. Scholastic grade point averages and scores on parent and teacher behavior problem-rating scales showed no group differences. Subjects used more school-based remedial services, although the trend did not achieve statistical significance. Parents reported spending more time with subjects than with control subjects helping with homework. These findings suggest that children who have recovered from meningitis due to H influenzae can maintain scores and grades comparable to their siblings as they progress to middle school. Their academic success may involve more school and family support to compensate for the mild differences in intelligence quotient and neuropsychologic testing found in the previous study.

  6. A chalcone with potent inhibiting activity against biofilm formation by nontypeable Haemophilus influenzae.

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    Kunthalert, Duangkamol; Baothong, Sudarat; Khetkam, Pichit; Chokchaisiri, Suwadee; Suksamrarn, Apichart

    2014-10-01

    Nontypeable Haemophilus influenzae (NTHi), an important human respiratory pathogen, frequently causes biofilm infections. Currently, resistance of bacteria within the biofilm to conventional antimicrobials poses a major obstacle to effective medical treatment on a global scale. Novel agents that are effective against NTHi biofilm are therefore urgently required. In this study, a series of natural and synthetic chalcones with various chemical substituents were evaluated in vitro for their antibiofilm activities against strong biofilm-forming strains of NTHi. Of the test chalcones, 3-hydroxychalcone (chalcone 8) exhibited the most potent inhibitory activity, its mean minimum biofilm inhibitory concentration (MBIC50 ) being 16 μg/mL (71.35 μM), or approximately sixfold more active than the reference drug, azithromycin (MBIC50 419.68 μM). The inhibitory activity of chalcone 8, which is a chemically modified chalcone, appeared to be superior to those of the natural chalcones tested. Significantly, chalcone 8 inhibited biofilm formation by all studied NTHi strains, indicating that the antibiofilm activities of this compound occur across multiple strong-biofilm forming NTHi isolates of different clinical origins. According to antimicrobial and growth curve assays, chalcone 8 at concentrations that decreased biofilm formation did not affect growth of NTHi, suggesting the biofilm inhibitory effect of chalcone 8 is non-antimicrobial. In terms of structure-activity relationship, the possible substituent on the chalcone backbone required for antibiofilm activity is discussed. These findings indicate that 3-hydroxychalcone (chalcone 8) has powerful antibiofilm activity and suggest the potential application of chalcone 8 as a new therapeutic agent for control of NTHi biofilm-associated infections. © 2014 The Societies and Wiley Publishing Asia Pty Ltd.

  7. In vitro activities and targets of three cephem antibiotics against Haemophilus influenzae.

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    Mendelman, P M; Henritzy, L L; Chaffin, D O; Lent, K; Smith, A L; Stull, T L; Wiley, E A

    1989-01-01

    The antimicrobial activities of cefixime, cefpodoxime, and ceftibuten were determined with 18 ampicillin-susceptible (Amps), 13 ampicillin-resistant beta-lactamase-producing (AmprBLP), and 7 ampicillin-resistant non-beta-lactamase-producing (AmprNBLP) strains of Haemophilus influenzae. An effect of inoculum density on apparent MIC, the bactericidal activity of these agents, and the targets of the three cephems were determined. The MICs of cefixime, cefpodoxime, and ceftibuten for 90% of the Amps and AmprBLP isolates were 0.04, 0.08, and 0.08 microgram/ml, respectively. In contrast, the MICs for 90% of the AmprNBLP strains were 0.96, 1.92, and 7.68 micrograms/ml. No significant inoculum effect was observed for any group of strains comparing inocula of 10(3) and 10(5) CFU, whereas only the AmprNBLP isolates showed a marked effect at an inoculum of 10(6) CFU. Although bactericidal levels were achieved for the Amps and AmprBLP strains, tolerance to cefixime and ceftibuten was observed. The bactericidal activity for the AmprNBLP strains was limited, with cefixime showing the highest activity of the three cephems. Penicillin-binding proteins 2, 4, and 5 revealed high affinity, with 50% inhibitory concentration levels below the MIC for all three cephems, suggesting that these are important targets of these agents in H. influenzae. We conclude that the cephems are highly active in vitro against Amps and AmprBLP strains of H. influenzae, but less so against AmprNBLP isolates. PMID:2610499

  8. Antimicrobial resistance genes in Actinobacillus pleuropneumoniae, Haemophilus parasuis and Pasteurella multocida isolated from Australian pigs.

    Science.gov (United States)

    Dayao, Dae; Gibson, J S; Blackall, P J; Turni, C

    2016-07-01

    To identify genes associated with the observed antimicrobial resistance in Actinobacillus pleuropneumoniae, Haemophilus parasuis and Pasteurella multocida isolated from Australian pigs. Isolates with known phenotypic resistance to β-lactams, macrolides and tetracycline were screened for the presence of antimicrobial resistance genes. A total of 68 A. pleuropneumoniae, 62 H. parasuis and 20 P. multocida isolates exhibiting phenotypic antimicrobial resistance (A. pleuropneumoniae and P. multocida) or elevated minimal inhibitory concentrations (MICs) (H. parasuis) to any of the following antimicrobial agents - ampicillin, erythromycin, penicillin, tetracycline, tilmicosin and tulathromycin - were screened for a total of 19 associated antimicrobial resistance genes (ARGs) by PCR. The gene bla ROB-1 was found in all ampicillin- and penicillin-resistant isolates, but none harboured the bla TEM-1 gene. The tetB gene was found in 76% (74/97) of tetracycline-resistant isolates, 49/53 A. pleuropneumoniae, 17/30 H. parasuis and 8/14 P. multocida. One A. pleuropneumoniae isolate harboured the tetH gene, but none of the 97 isolates had tetA, tetC, tetD, tetE, tetL, tetM or tetO. A total of 92 isolates were screened for the presence of macrolide resistance genes. None was found to have ermA, ermB, ermC, erm42, mphE, mefA, msrA or msrE. The current study has provided a genetic explanation for the resistance or elevated MIC of the majority of isolates of Australian porcine respiratory pathogens to ampicillin, penicillin and tetracycline. However, the macrolide resistance observed by phenotypic testing remains genetically unexplained and further studies are required. © 2016 Australian Veterinary Association.

  9. Acute Exacerbations in COPD and their Control with Oral Immunisation with nontypeable Haemophilus influenzae

    Directory of Open Access Journals (Sweden)

    Robert eClancy

    2011-03-01

    Full Text Available Chronic obstructive pulmonary disease (COPD a term based on the demonstration of irreversible airways obstruction, introduced to unify a range of chronic progressive diseases of the airways consequent upon inhalation of toxins. While disease is initiated and progressed by inhaled toxins, an additional pathway of damage has emerged, with particular relevance to acute exacerbations. Exacerbations of disease due to an increase in the level of intra-bronchial inflammation have taken on a new significance as their role in determining both acute and chronic outcomes is better understood. This ‘second pathway’ of disease is a consequence of bacterial colonisation of damaged airways. Although bacteria have been linked to acute episodes in COPD over 50 years, only recently has quality data on antibiotic usage and the detection of ‘exacerbation isolates’ of non-typeable Haemophilus influenzae (NTHi provided strong argument in support of a pathogenic role. Yet a poor correlation between detection of colonising bacteria and clinical status remained a concern in attempts to explain a role for bacteria in a classical infection model. This presentation discusses a hypothesis that acute exacerbations reflect a T-cell dependent hypersensitivity response to colonising bacteria, with IL-17 dependent accumulation of neutrophils within the bronchus, as the main outcome measure. Critical protection against exacerbations following oral administration of NTHi, an immunotherapy that drives a TH17 Tcell response from Peyer’s patches, reduces the load of intrabronchial bacteria while preventing access of inhaled bacteria into small airways. Immunotherapy augments a physiological ‘loop’ based on aspiration of bronchus content into the gut. A second ‘hypersensitivity’ mechanism may cause bronchospasm – in both COPD and treatment-resistant asthma – due to specific IgE antibody directed against colonising bacteria, as oral NTHi abrogates wheeze in

  10. Impacto de la vacunación contra Haemophilus influenzae tipo b en Cuba

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    Dickinson Félix O.

    2001-01-01

    Full Text Available Objetivo. Determinar el impacto de la vacunación de menores de 2 años en Cuba contra Haemophilus influenzae tipo b (Hib, principal agente causal de la meningitis bacteriana en ese país. Métodos. La disponibilidad de vacunas conjugadas eficaces contra Hib motivó la vacunación nacional en 1999 de niños menores de 2 años, que alcanzó una cobertura de 97%. El impacto se evaluó mediante el Sistema Nacional de Vigilancia de Meningoencefalitis Bacterianas (SNVMEB. Resultados. La eficacia global de la vacunación se estimó en 99% y la incidencia general de la meningoencefalitis por Hib disminuyó de 1,3 a 0,6 por 100 000 habitantes (46,1%, observándose la mayor reducción en niños menores de 5 años (56,1%. En los menores de 1 año se redujo 70,5% y en el resto de los grupos de menores de 5 años disminuyó entre 25,9 y 49,6%. En el grupo diana para la vacunación, la incidencia se redujo 61,1%; entre los niños de este grupo que contrajeron la meningoencefalitis por Hib, solamente 8 (24,2% estaban vacunados, 7 de ellos con una sola dosis, aplicada 1 mes antes de enfermar. Conclusiones. Se ha demostrado que la vacunación a gran escala de los niños menores de 2 años contra Hib en Cuba a través del SNVMEB ha logrado disminuir notablemente la incidencia de meningoencefalitis por Hib.

  11. Molecular Characterization of Fluoroquinolone Resistance in Nontypeable Haemophilus influenzae Clinical Isolates

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    Puig, Carmen; Tirado-Vélez, José Manuel; Calatayud, Laura; Tubau, Fe; Garmendia, Junkal; Ardanuy, Carmen; Marti, Sara

    2014-01-01

    Nontypeable Haemophilus influenzae (NTHi) is a common cause of respiratory infections in adults, who are frequently treated with fluoroquinolones. The aims of this study were to characterize the genotypes of fluoroquinolone-resistant NTHi isolates and their mechanisms of resistance. Among 7,267 H. influenzae isolates collected from adult patients from 2000 to 2013, 28 (0.39%) were ciprofloxacin resistant according to Clinical and Laboratory Standards Institute (CLSI) criteria. In addition, a nalidixic acid screening during 2010 to 2013 detected five (0.23%) isolates that were ciprofloxacin susceptible but nalidixic acid resistant. Sequencing of their quinolone resistance-determining regions and genotyping by pulse-field gel electrophoresis and multilocus sequence typing of the 25 ciprofloxacin-resistant isolates available and all 5 nalidixic acid-resistant isolates were performed. In the NTHi isolates studied, two mutations producing changes in two GyrA residues (Ser84, Asp88) and/or two ParC residues (Ser84, Glu88) were associated with increased fluoroquinolone MICs. Strains with one or two mutations (n = 15) had ciprofloxacin and levofloxacin MICs of 0.12 to 2 μg/ml, while those with three or more mutations (n = 15) had MICs of 4 to 16 μg/ml. Long persistence of fluoroquinolone-resistant strains was observed in three chronic obstructive pulmonary disease patients. High genetic diversity was observed among fluoroquinolone-resistant NTHi isolates. Although fluoroquinolones are commonly used to treat respiratory infections, the proportion of resistant NTHi isolates remains low. The nalidixic acid disk test is useful for detecting the first changes in GyrA or in GyrA plus ParC among fluoroquinolone-susceptible strains that are at a potential risk for the development of resistance under selective pressure by fluoroquinolone treatment. PMID:25385097

  12. Invasive Haemophilus influenzae disease in the vaccine era in Rio de Janeiro, Brazil

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    Mari Tuyama

    Full Text Available BACKGROUND Haemophilus influenzae (Hi serotype b (Hib conjugate vaccine was incorporated into the infant immunisation schedule in Brazil in 1999, where Hib was one of the major etiologic sources of community-acquired bacterial meningitis. OBJECTIVES The purpose of this study is to describe the molecular epidemiology of invasive Hi disease in Rio de Janeiro state, Brazil, before and after vaccine introduction. METHODS Surveillance data from 1986 to 2014 were analysed. Hi isolates recovered from cerebrospinal fluid (CSF or blood from 1993 to 2014 were serotyped by slide agglutination, genotyped by multilocus sequence typing (MLST, and the capsule type evaluation, differentiation of serologically non-typeable isolates, and characterisation of the capsule (cap locus was done by polymerase chain reaction. Antimicrobial susceptibility testing was performed using E-test. FINDINGS From 1986 to 1999 and from 2000 to 2014, 2580 and 197 (42% without serotype information confirmed cases were reported, respectively. The case fatality rate was 17% and did not correlate with the strain. Hib and b- variant isolates belonged to ST-6, whereas serotype a isolates belonged to the ST-23 clonal complex. Serotype a appeared to emerge during the 2000s. Non-encapsulated isolates were non-clonal and distinct from the encapsulated isolates. Ampicillin-resistant isolates were either of serotype b or were non-encapsulated, and all of them were β-lactamase-positive but amoxicillin-clavulanic acid susceptible. MAIN CONCLUSIONS Although Hi meningitis became a relatively rare disease in Rio de Janeiro after the introduction of the Hib conjugate vaccine, the isolates recovered from patients have become more diverse. These results indicate the need to implement an enhanced surveillance system to continue monitoring the impact of the Hib conjugate vaccine.

  13. Haemophilus influenzae type b carriage and novel bacterial population structure among children in urban Kathmandu, Nepal.

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    Williams, E J; Lewis, J; John, T; Hoe, J C; Yu, L; Dongol, S; Kelly, D F; Griffiths, D T; Shah, A; Limbu, B; Pradhan, R; Mawas, F; Shrestha, S; Thorson, S; Werno, A M; Murdoch, D R; Adhikari, N; Pollard, A J

    2011-04-01

    Haemophilus influenzae type b (Hib) is a major cause of invasive bacterial infection in children that can be prevented by a vaccine, but there is still uncertainty about its relative importance in Asia. This study investigated the age-specific prevalence of Hib carriage and its molecular epidemiology in carriage and disease in Nepal. Oropharyngeal swabs were collected from children in Kathmandu, Nepal, from 3 different settings: a hospital outpatient department (OPD), schools, and children's homes. Hib was isolated using Hib antiserum agar plates, and serotyping was performed with latex agglutination. Hib isolates from children with invasive disease were obtained during active microbiological surveillance at Patan Hospital, Kathmandu, Nepal. Genotyping of disease and carriage isolates was undertaken using multilocus sequence typing (MLST). Swabs were taken from 2,195 children, including 1,311 children at an OPD, 647 children attending schools, and 237 children in homes. Overall, Hib was identified in 5.0% (110/2,195; 95% confidence interval [95% CI], 3.9% to 6.4%). MLST was performed on 108 Hib isolates from children carrying Hib isolates and 15 isolates from children with invasive disease. Thirty-one sequence types (STs) were identified, and 20 of these were novel STs. The most common ST isolates were sequence type 6 (ST6) and the novel ST722. There was marked heterogeneity among the STs from children with disease and children carrying Hib. STs identified from invasive infections were those commonly identified in carriage. This study provides evidence of Hib carriage among children in urban Nepal with genetically diverse strains prior to introduction of universal vaccination. The Hib carriage rate in Nepal was similar to the rates observed in other populations with documented high disease rates prior to vaccination, supporting implementation of Hib vaccine in Nepal in 2009.

  14. Economic evaluations of Haemophilus influenzae type b (Hib) vaccine: a systematic review.

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    Chongmelaxme, Bunchai; Hammanee, Maythika; Phooaphirak, Wariya; Kotirum, Surachai; Hutubessy, Raymond; Chaiyakunapruk, Nathorn

    2017-10-01

    The World Health Organization (WHO) recommends the use of Haemophilus influenzae type b (Hib) conjugate vaccines, but China and Thailand have not used Hib vaccination in their national immunization programs. This systematic review aimed to update published economic evaluations of Hib vaccinations and to determine factors that potentially affected their cost-effectiveness. Searches were performed from the inception until December 2015 using 13 databases: CAB direct; CEA registry; EconLit; EMBASE; E-library; NHSEED; PAHO; POPLINE; PubMed; Redalyc project; RePEc; SciELO; and WHOLIS. Reference lists of relevant studies and grey literature were also searched. Full economic evaluations of Hib vaccination with results of costs and outcomes were included. The WHO checklist was used to evaluate the quality of the included studies. Data from eligible studies were extracted using a standardized data collection form. Out of 830 articles, 27 were included. Almost half of the studies (12/27) were conducted in high-income countries. Twelve studies (12/27) investigated the Hib vaccine as an addition to the existing vaccination program. Most studies (17/27) examined a 3-dose schedule of Hib vaccine. Nineteen studies (19/27) reported the model used, where all were decision tree models. Most of the studies (23/27) demonstrated an economic value of Hib vaccination programs, key influential parameters being incidence rates of Hib disease and vaccine price. Hib vaccination programs are mostly found to be cost-effective across geographic regions and country income levels, and Hib vaccination is recommended for inclusion into all national immunization programs. The findings are expected to support policy-makers for making decisions on allocating limited resources of the Hib vaccination program effectively.

  15. Maturation of molybdoenzymes and its influence on the pathogenesis of non-typeable Haemophilus influenzae.

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    Dhouib, Rabeb; Pg Othman, Dk S M; Essilfie, Ama-Tawiah; Hansbro, Phil M; Hanson, Jeffrey O; McEwan, Alastair G; Kappler, Ulrike

    2015-01-01

    Mononuclear molybdenum enzymes of the dimethylsulfoxide (DMSO) reductase family occur exclusively in prokaryotes, and a loss of some these enzymes has been linked to a loss of bacterial virulence in several cases. The MobA protein catalyzes the final step in the synthesis of the molybdenum guanine dinucleotide (MGD) cofactor that is exclusive to enzymes of the DMSO reductase family. MobA has been proposed as a potential target for control of virulence since its inhibition would affect the activities of all molybdoenzymes dependent upon MGD. Here, we have studied the phenotype of a mobA mutant of the host-adapted human pathogen Haemophilus influenzae. H. influenzae causes and contributes to a variety of acute and chronic diseases of the respiratory tract, and several enzymes of the DMSO reductase family are conserved and highly expressed in this bacterium. The mobA mutation caused a significant decrease in the activities of all Mo-enzymes present, and also resulted in a small defect in anaerobic growth. However, we did not detect a defect in in vitro biofilm formation nor in invasion and adherence to human epithelial cells in tissue culture compared to the wild-type. In a murine in vivo model, the mobA mutant showed only a mild attenuation compared to the wild-type. In summary, our data show that MobA is essential for the activities of molybdenum enzymes, but does not appear to affect the fitness of H. influenzae. These results suggest that MobA is unlikely to be a useful target for antimicrobials, at least for the purpose of treating H. influenzae infections.

  16. Maturation of molybdoenzymes and its influence on the pathogenesis of non-typeable Haemophilus influenzae

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    Rabeb eDhouib

    2015-11-01

    Full Text Available Mononuclear molybdenum enzymes of the dimethylsulfoxide (DMSO reductase family occur exclusively in prokaryotes, and a loss of some these enzymes has been linked to a loss of bacterial virulence in several cases. The MobA protein catalyzes the final step in the synthesis of the molybdenum guanine dinucleotide (MGD cofactor that is exclusive to enzymes of the DMSO reductase family. MobA has been proposed as a potential target for control of virulence since its inhibition would affect the activities of all molybdoenzymes dependent upon MGD. Here, we have studied the phenotype of a mobA mutant of the host-adapted human pathogen Haemophilus influenzae. H. influenzae causes and contributes to a variety of acute and chronic diseases of the respiratory tract., and several enzymes of the DMSO reductase family are conserved and highly expressed in this bacterium. The mobA mutation caused a significant decrease in the activities of all Mo-enzymes present, and also resulted in a small defect in anaerobic growth. However, we did not detect a defect in in vitro biofilm formation nor in invasion and adherence to human epithelial cells in tissue culture compared to the wild-type. In a murine in vivo model, the mobA mutant showed only a mild attenuation compared to the wild-type. In summary, our data show that MobA is essential for the activities of molybdenum enzymes, but does not appear to affect the fitness of H. influenzae. These results suggest that MobA is unlikely to be a useful target for antimicrobials, at least for the purpose of treating H. influenzae infections.

  17. Bacterial bronchitis caused by Streptococcus pneumoniae and nontypable Haemophilus influenzae in children: the impact of vaccination.

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    Priftis, Kostas N; Litt, David; Manglani, Sapna; Anthracopoulos, Michael B; Thickett, Keith; Tzanakaki, Georgina; Fenton, Patricia; Syrogiannopoulos, George A; Vogiatzi, Aliki; Douros, Konstantinos; Slack, Mary; Everard, Mark L

    2013-01-01

    Protracted bacterial bronchitis is a major cause of persistent cough in childhood. The organisms most commonly isolated are nontypable Haemophilus influenzae and Streptococcus pneumoniae . There are no studies addressing typing of these organisms when recovered from the lower airways. Isolates of these two organisms (identified in BAL samples from children undergoing routine investigation of a chronic cough thought to be attributable to a protracted bacterial bronchitis) were subject to typing. Samples were collected in Sheffield, England, and Athens, Greece. The majority of the children from Sheffield had received pneumococcal-conjugate vaccines 7 or 13 (PCV-7 or PCV-13) conjugate vaccine but only a minority of Greek children had received PCV-7. All 18 S pneumoniae isolates from Greek BAL samples are serotypes contained in PCV-13 while 10 are contained in PCV-7. In contrast, 28 of the 39 samples from Sheffield contained serotypes that are not included in PCV-13. All 26 of the nontypable H influenzae samples obtained in Sheffield produced distinct multilocus variable-number tandem repeat analysis profiles. There was a significant difference between children from Athens and Sheffield in the distribution of serotypes contained or not contained in the pneumococcal vaccine ( P = .04). More specifically, immunization with pneumococcal vaccine was related with isolation of S pneumoniae serotypes not included in the vaccine (OR, 0.021; CI, 0.003-0.115; P < .001). The data suggest that both vaccine and nonvaccine S pneumoniae serotypes may play a role in protracted bacterial bronchitis and provide some hints that serotype replacement may occur in response to the introduction of conjugate vaccines.

  18. Accelerating Policy Decisions to Adopt Haemophilus influenzae Type b Vaccine: A Global, Multivariable Analysis

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    Shearer, Jessica C.; Stack, Meghan L.; Richmond, Marcie R.; Bear, Allyson P.; Hajjeh, Rana A.; Bishai, David M.

    2010-01-01

    Background Adoption of new and underutilized vaccines by national immunization programs is an essential step towards reducing child mortality. Policy decisions to adopt new vaccines in high mortality countries often lag behind decisions in high-income countries. Using the case of Haemophilus influenzae type b (Hib) vaccine, this paper endeavors to explain these delays through the analysis of country-level economic, epidemiological, programmatic and policy-related factors, as well as the role of the Global Alliance for Vaccines and Immunisation (GAVI Alliance). Methods and Findings Data for 147 countries from 1990 to 2007 were analyzed in accelerated failure time models to identify factors that are associated with the time to decision to adopt Hib vaccine. In multivariable models that control for Gross National Income, region, and burden of Hib disease, the receipt of GAVI support speeded the time to decision by a factor of 0.37 (95% CI 0.18–0.76), or 63%. The presence of two or more neighboring country adopters accelerated decisions to adopt by a factor of 0.50 (95% CI 0.33–0.75). For each 1% increase in vaccine price, decisions to adopt are delayed by a factor of 1.02 (95% CI 1.00–1.04). Global recommendations and local studies were not associated with time to decision. Conclusions This study substantiates previous findings related to vaccine price and presents new evidence to suggest that GAVI eligibility is associated with accelerated decisions to adopt Hib vaccine. The influence of neighboring country decisions was also highly significant, suggesting that approaches to support the adoption of new vaccines should consider supply- and demand-side factors. Please see later in the article for the Editors' Summary PMID:20305714

  19. Complete Deletion of the Fucose Operon in Haemophilus influenzae Is Associated with a Cluster in Multilocus Sequence Analysis-Based Phylogenetic Group II Related to Haemophilus haemolyticus: Implications for Identification and Typing.

    Science.gov (United States)

    de Gier, Camilla; Kirkham, Lea-Ann S; Nørskov-Lauritsen, Niels

    2015-12-01

    Nonhemolytic variants of Haemophilus haemolyticus are difficult to differentiate from Haemophilus influenzae despite a wide difference in pathogenic potential. A previous investigation characterized a challenging set of 60 clinical strains using multiple PCRs for marker genes and described strains that could not be unequivocally identified as either species. We have analyzed the same set of strains by multilocus sequence analysis (MLSA) and near-full-length 16S rRNA gene sequencing. MLSA unambiguously allocated all study strains to either of the two species, while identification by 16S rRNA sequence was inconclusive for three strains. Notably, the two methods yielded conflicting identifications for two strains. Most of the "fuzzy species" strains were identified as H. influenzae that had undergone complete deletion of the fucose operon. Such strains, which are untypeable by the H. influenzae multilocus sequence type (MLST) scheme, have sporadically been reported and predominantly belong to a single branch of H. influenzae MLSA phylogenetic group II. We also found evidence of interspecies recombination between H. influenzae and H. haemolyticus within the 16S rRNA genes. Establishing an accurate method for rapid and inexpensive identification of H. influenzae is important for disease surveillance and treatment. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  20. Quantitation of antibody-secreting cells in the blood after vaccination with Haemophilus influenzae type b conjugate vaccine

    DEFF Research Database (Denmark)

    Barington, T; Heilmann, C; Andersen, V

    1990-01-01

    The human B-lymphocyte response to protein-conjugated polysaccharide antigens has not previously been studied at the cellular level. In order to do so, we developed and evaluated haemolytic plaque-forming cell assays detecting Haemophilus influenzae type b (Hib) capsular polysaccharide-specific a......The human B-lymphocyte response to protein-conjugated polysaccharide antigens has not previously been studied at the cellular level. In order to do so, we developed and evaluated haemolytic plaque-forming cell assays detecting Haemophilus influenzae type b (Hib) capsular polysaccharide......-specific antibody-secreting cells (AbSC) of the isotypes IgM, IgG, and IgA. The appearance of AbSC in the blood after vaccination of adults with diphtheria toxoid-conjugated Hib polysaccharide was investigated. AbSC were detected from post-vaccination day 5 to day 14. IgA was the predominant isotype among...... these cells. IgM AbSC peaked slightly earlier (median day 7) than IgG and IgA AbSC (both day 8). On post-vaccination day 8 the numbers of AbSC were: IgA, 1217/10(6) mononuclear cells (median); IgG, 211; and IgM, 30 (n = 11). Similar isotype distribution has earlier been found after vaccination with pure...

  1. Detection of Haemophilus influenzae in respiratory secretions from pneumonia patients by quantitative real-time polymerase chain reaction.

    Science.gov (United States)

    Abdeldaim, Guma M K; Strålin, Kristoffer; Kirsebom, Leif A; Olcén, Per; Blomberg, Jonas; Herrmann, Björn

    2009-08-01

    A quantitative real-time polymerase chain reaction (PCR) based on the omp P6 gene was developed to detect Haemophilus influenzae. Its specificity was determined by analysis of 29 strains of 11 different Haemophilus spp. and was compared with PCR assays having other target genes: rnpB, 16S rRNA, and bexA. The method was evaluated on nasopharyngeal aspirates from 166 adult patients with community-acquired pneumonia. When 10(4) DNA copies/mL was used as cutoff limit for the method, P6 PCR had a sensitivity of 97.5% and a specificity of 96.0% compared with the culture. Of 20 culture-negative but P6 PCR-positive cases, 18 were confirmed by fucK PCR as H. influenzae. Five (5.9%) of 84 nasopharyngeal aspirates from adult controls tested PCR positive. We conclude that the P6 real-time PCR is both sensitive and specific for identification of H. influenzae in respiratory secretions. Quantification facilitates discrimination between disease-causing H. influenzae strains and commensal colonization.

  2. Antimicrobial resistance among invasive Haemophilus influenzae strains: results of a Brazilian study carried out from 1996 through 2000

    Directory of Open Access Journals (Sweden)

    Casagrande S.T.

    2002-01-01

    Full Text Available A total of 1712 strains of Haemophilus influenzae isolated from patients with invasive diseases were obtained from ten Brazilian states from 1996 to 2000. ß-Lactamase production was assessed and the minimum inhibitory concentrations (MIC of ampicillin, chloramphenicol, ceftriaxone and rifampin were determined using a method for broth microdilution of Haemophilus test medium. The prevalence of strains producing ß-lactamase ranged from 6.6 to 57.7%, with an overall prevalence of 18.4%. High frequency of ß-lactamase-mediated ampicillin resistance was observed in Distrito Federal (25%, São Paulo (21.7% and Paraná (18.5%. Of the 1712 strains analyzed, none was ß-lactamase negative, ampicillin resistant. A total of 16.8% of the strains were resistant to chloramphenicol, and 13.8% of these also presented resistance to ampicillin, and only 3.0% were resistant to chloramphenicol alone. All strains were susceptible to ceftriaxone and rifampin and the MIC90 were 0.015 µg/ml and 0.25 µg/ml, respectively. Ceftriaxone is the drug of choice for empirical treatment of bacterial meningitis in pediatric patients who have not been screened for drug susceptibility. The emergence of drug resistance is a serious challenge for the management of invasive H. influenzae disease, which emphasizes the fundamental role of laboratory-based surveillance for antimicrobial resistance.

  3. A simplification of the enzyme-linked immunospot technique. Increased sensitivity for cells secreting IgG antibodies to Haemophilus influenzae type b capsular polysaccharide

    DEFF Research Database (Denmark)

    Barington, T; Sparholt, S; Juul, L

    1992-01-01

    A simplified enzyme-linked immunospot (ELISPOT) technique is described for the detection of cells secreting antibodies to tetanus toxoid (TT), diphtheria toxoid (DT) or Haemophilus influenzae type b capsular polysaccharide (PRP). By combining the cell suspension with the enzyme-linked secondary...... of polysaccharide-specific antibody-secreting cells....

  4. Increased biofilm formation by nontypeable Haemophilus influenzae isolates from patients with invasive disease or otitis media versus strains recovered from cases of respiratory infections

    NARCIS (Netherlands)

    Puig, C.; Domenech, A.; Garmendia, J.; Langereis, J.D.; Mayer, P.; Calatayud, L.; Linares, J.; Ardanuy, C.; Marti, S.

    2014-01-01

    Biofilm formation by nontypeable (NT) Haemophilus influenzae remains a controversial topic. Nevertheless, biofilm-like structures have been observed in the middle-ear mucosa of experimental chinchilla models of otitis media (OM). To date, there have been no studies of biofilm formation in large

  5. TEM-1 AND ROB-1 PRESENCE AND ANTIMICROBIAL RESISTANCE IN HAEMOPHILUS INFLUENZAE STRAINS, ISTANBUL, TURKEY.

    Science.gov (United States)

    Kuvat, Nuray; Nazik, Hasan; Berkiten, Rahmiye; Öngen, Betigül

    2015-03-01

    Resistance of 235 Haemophilus influenzae clinical isolates from Istanbul Medical Faculty Hospital, Turkey were determined against 19 antibiotics by disc diffusion method, and minimum inhibitory concentrations (MICs) of those found resistant to ampicillin, cefuroxim, chloramphenicol and meropenem were measured using E-test. Ampicillin-resistant isolates producing beta-lactamase as demonstrated by a nitrocefin assay were analyzed for the presence of TEM-1 and ROB-1 genes by PCR. Eleven percent of the isolates were resistant to ampicillin (10 µg/ml), of which 73% were beta-lactamase positive and carried TEM-1 gene, but none were positive for ROB-1 gene. All isolates susceptible to amoxicillin-clavulanate (20/10 µg/ml), azithromycin (15 µg/ml), aztreonam (30 µg/ml), cefotaxime (30 µg/ml), ceftriaxone (30 µg/ml), ciprofloxacin (5 µg/ml), levofloxacin (5 µg/ml), and telithromycin (15 µg/ml) but 24%, 15%, 4%, 4%, 2%, 1%, 1%, 0.5%, 0.5% and 0.5% were resistant to trimethoprim-sulfamethoxazole (1.25/23.75 µg/ml), tetracycline (30 µg/ml), cefaclor (30 µg/ml), clarithromycin (15 µg/ml), cefuroxime (30 µg/ml), meropenem (10 µg/ml), chloramphenicol (30 µg/ml), ampicillin-sulbactam (10/10 µg/ml), nalidixic acid (30 µg/ml), and fosfomycin (30 µg/ml), respectively. MIC values of three cefuroxime-resistant isolates was 24, 48 and > 256 µg/ml, respectively; of two meropenem-resistant strains > 256 µg/ml; and of two chloramphenicol-susceptible isolates (by disc diffusion method) 6 µg/ml (considered as intermediate susceptible). Multiple- antibiotics resistance was detected in 15% of the strains, with resistance to 2, 3, 4, 5 and 6 antibiotics in 8.5%, 4%, 2%, 0.5% and 0.5% of the isolates, respectively. By identifying beta-lactamase-negative ampicillin-resistant H. influenzae, empirical therapy with beta-lactam/beta-lactamase inhibitor combinations and second generation cephalosporins would be inappropriate for such patients (approximately 3%). Our findings will

  6. Construction of non-polar mutants in Haemophilus influenzae using FLP recombinase technology

    Directory of Open Access Journals (Sweden)

    Baker Beth D

    2008-11-01

    Full Text Available Abstract Background Nontypeable Haemophilus influenzae (NTHi is a gram-negative bacterium that causes otitis media in children as well as other infections of the upper and lower respiratory tract in children and adults. We are employing genetic strategies to identify and characterize virulence determinants in NTHi. NTHi is naturally competent for transformation and thus construction of most mutants by common methodologies is relatively straightforward. However, new methodology was required in order to construct unmarked non-polar mutations in poorly expressed genes whose products are required for transformation. We have adapted the lambda red/FLP-recombinase-mediated strategy used in E. coli for use in NTHi. Results A cassette containing a spectinomycin resistance gene and an rpsL gene flanked by FRT sites was constructed. A PCR amplicon containing 50 base pairs of DNA homologous to the 5' and 3' ends of the gene to be disrupted and the cassette was generated, then recombineered into the target NTHi gene, cloned on a plasmid, using the lambda recombination proteins expressed in E. coli DY380. Thus, the gene of interest was replaced by the cassette. The construct was then transformed into a streptomycin resistant NTHi strain and mutants were selected on spectinomycin-containing growth media. A plasmid derived from pLS88 with a temperature sensitive replicon expressing the FLP recombinase gene under the control of the tet operator/repressor was constructed. This plasmid was electroporated into the NTHi mutant at the permissive temperature and FLP expression was induced using anhydrotetracycline. The recombinase recognizes the FRT sites and eliminates the antibiotic cassette by site-specific recombination, creating the unmarked non-polar mutation. The plasmid is cured by growth of cells at the restrictive temperature. Conclusion The products of the genes in the NTHi pilABCD operon are required for type IV pilus biogenesis and have a role in

  7. Expression of the Flp proteins by Haemophilus ducreyi is necessary for virulence in human volunteers

    Directory of Open Access Journals (Sweden)

    Zwickl Beth W

    2011-09-01

    Full Text Available Abstract Background Haemophilus ducreyi, the causative agent of the sexually transmitted disease chancroid, contains a flp (fimbria like protein operon that encodes proteins predicted to contribute to adherence and pathogenesis. H. ducreyi mutants that lack expression of Flp1 and Flp2 or TadA, which has homology to NTPases of type IV secretion systems, have decreased abilities to attach to and form microcolonies on human foreskin fibroblasts (HFF. A tadA mutant is attenuated in its ability to cause disease in human volunteers and in the temperature dependent rabbit model, but a flp1flp2 mutant is virulent in rabbits. Whether a flp deletion mutant would cause disease in humans is not clear. Results We constructed 35000HPΔflp1-3, a deletion mutant that lacks expression of all three Flp proteins but has an intact tad secretion system. 35000HPΔflp1-3 was impaired in its ability to form microcolonies and to attach to HFF in vitro when compared to its parent (35000HP. Complementation of the mutant with flp1-3 in trans restored the parental phenotype. To test whether expression of Flp1-3 was necessary for virulence in humans, ten healthy adult volunteers were experimentally infected with a fixed dose of 35000HP (ranging from 54 to 67 CFU on one arm and three doses of 35000HPΔflp1-3 (ranging from 63 to 961 CFU on the other arm. The overall papule formation rate for the parent was 80% (95% confidence interval, CI, 55.2%-99.9% and for the mutant was 70.0% (95% CI, 50.5%-89.5% (P = 0.52. Mutant papules were significantly smaller (mean, 11.2 mm2 than were parent papules (21.8 mm2 24 h after inoculation (P = 0.018. The overall pustule formation rates were 46.7% (95% CI 23.7-69.7% at 30 parent sites and 6.7% (95% CI, 0.1-19.1% at 30 mutant sites (P = 0.001. Conclusion These data suggest that production and secretion of the Flp proteins contributes to microcolony formation and attachment to HFF cells in vitro. Expression of flp1-3 is also necessary for H

  8. WITHDRAWN: Haemophilus influenzae oral whole cell vaccination for preventing acute exacerbations of chronic bronchitis.

    Science.gov (United States)

    Foxwell, A Ruth; Cripps, Allan W; Dear, Keith Bg

    2010-10-06

    Acute bronchitis leading to ongoing exacerbations is a serious condition predisposed to by viruses, bacteria or environmental factors. It can be fatal. Antibiotic therapy is not particularly useful. An oral Haemophilus influenzae vaccine has been developed. To assess the effects of an oral, monobacterial whole-cell, killed, nontypeable H. influenzae vaccine in protecting against recurrent acute episodes in chronic bronchitis. In this updated review, we searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 1, 2006), MEDLINE (1966 to January Week 4 2006), EMBASE (1990 to September 2005) and ISI Current Contents (2004 to May 2006). Randomised controlled trials (RCTs) comparing the effects of the H. influenzae vaccine on patients with recurrent acute exacerbations of chronic bronchitis were included when there was overt matching of the vaccine and placebo groups on clinical grounds. Three authors extracted data and assessed trial quality independently from original records and publications for incidence and severity of bronchitis episodes and carriage rate of nontypeable H. influenzae measured in the upper respiratory tract every three months following vaccination. Six trials were included in the study with a total of 440 participants. The vaccine reduced the incidence of bronchitic episodes at three months after vaccination (rate ratio is 0.69; 95% CI 0.41 to 1.14) and at six months after vaccination (rate ratio 0.82; 95% CI 0.62 to 1.09). If these results been statistically significant, they would have represented a reduction in acute bronchitic attacks for vaccinated individuals of 31% at three months, and 18% at six. The effect had disappeared by nine months. The severity of exacerbations in the treatment group, as measured by requirement to prescribe antibiotics, was likewise reduced by 58% at three months (Peto odds ratio = 0.42; 95% CI 0.16 to 1.13), and by 65% at six months (Peto odds ratio = 0.35; 95% CI 0.16 to 0

  9. Identification and characterization of a nontypeable Haemophilus influenzae putative toxin-antitoxin locus

    Directory of Open Access Journals (Sweden)

    Smith Arnold L

    2004-07-01

    Full Text Available Abstract Background Certain strains of an obligate parasite of the human upper respiratory tract, nontypeable Haemophilus influenzae (NTHi, can cause invasive diseases such as septicemia and meningitis, as well as chronic mucosal infections such as otitis media. To do this, the organism must invade and survive within both epithelial and endothelial cells. We have identified a facilitator of NTHi survival inside human cells, virulence-associated protein D (vapDHi, encoded by gene HI0450. Both vapDHi and a flanking gene, HI0451, exhibit the genetic and physical characteristics of a toxin/antitoxin (TA locus, with VapDHi serving as the toxin moiety and HI0451 as the antitoxin. We propose the name VapXHi for the HI0451 antitoxin protein. Originally identified on plasmids, TA loci have been found on the chromosomes of a number of bacterial pathogens, and have been implicated in the control of translation during stressful conditions. Translation arrest would enhance survival within human cells and facilitate persistent or chronic mucosal infections. Results Isogenic mutants in vapDHi were attenuated for survival inside human respiratory epithelial cells (NCI-H292 and human brain microvascular endothelial cells (HBMEC, the in vitro models of mucosal infection and the blood-brain barrier, respectively. Transcomplementation with a vapDHi allele restored wild-type NTHi survival within both cell lines. A PCR survey of 59 H. influenzae strains isolated from various anatomical sites determined the presence of a vapDHiallele in 100% of strains. Two isoforms of the gene were identified in this population; one that was 91 residues in length, and another that was truncated to 45 amino acids due to an in-frame deletion. The truncated allele failed to transcomplement the NTHi vapDHi survival defect in HBMEC. Subunits of full-length VapDHi homodimerized, but subunits of the truncated protein did not. However, truncated protein subunits did interact with full

  10. Ampicillin resistance in Haemophilus influenzae from COPD patients in the UK

    Directory of Open Access Journals (Sweden)

    Maddi S

    2017-05-01

    Full Text Available Satyanarayana Maddi,1 Umme Kolsum,1 Sarah Jackson,1 Richard Barraclough,2 Barbara Maschera,3 Karen D Simpson,3 Thierry G Pascal,4 Serge Durviaux,4 Edith M Hessel,3 Dave Singh1 1Division of Infection, Immunity and Respiratory Medicine, Medicines Evaluation Unit, University Hospital of South Manchester Foundation Trust, University of Manchester, 2Department of Respiratory Medicine, University Hospital of South Manchester Foundation Trust, Manchester, 3Refractory Respiratory Inflammation DPU, GlaxoSmithKline Medicines Research Centre, Stevenage, Hertfordshire, UK; 4Clinical Laboratory Sciences, GlaxoSmithKline Vaccines, Wavre, Belgium Background: Haemophilus influenzae is commonly isolated from the airways of COPD patients. Antibiotic treatment may cause the emergence of resistant H. influenzae strains, particularly ampicillin-resistant strains, including β-lactamase-negative ampicillin resistance (BLNAR strains. Genetic identification using ftsI sequencing is the optimum method for identifying mutations within BLNAR strains. The prevalence of BLNAR in COPD patients during the stable state has not been reported. We investigated the antibiotic resistance patterns of H. influenzae present in the sputum of stable COPD patients, focusing on ampicillin resistance; the prevalence of enzyme and non-enzyme-mediated ampicillin resistance was determined. A subset of patients was followed up longitudinally to study H. influenzae strain switching and antibiotic sensitivity changes.Patients and methods: Sputum sampling was performed in 61 COPD patients, with 42 samples obtained at baseline; H. influenzae was detected by polymerase chain reaction in 28 samples. In all, 45 patients completed the follow-up for 2 years; 24 H. influenzae isolates were obtained.Results: Disk diffusion showed the highest antibiotic resistance in the penicillin antibiotic group (eg, 67% for ampicillin and macrolides (eg, 46% for erythromycin, whereas all isolates were susceptible to

  11. Exposure Forecaster

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Exposure Forecaster Database (ExpoCastDB) is EPA's database for aggregating chemical exposure information and can be used to help with chemical exposure...

  12. Rapid Differentiation of Haemophilus influenzae and Haemophilus haemolyticus by Use of Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry with ClinProTools Mass Spectrum Analysis.

    Science.gov (United States)

    Chen, Jonathan H K; Cheng, Vincent C C; Wong, Chun-Pong; Wong, Sally C Y; Yam, Wing-Cheong; Yuen, Kwok-Yung

    2017-09-01

    Haemophilus influenzae is associated with severe invasive disease, while Haemophilus haemolyticus is considered part of the commensal flora in the human respiratory tract. Although the addition of a custom mass spectrum library into the matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) system could improve identification of these two species, the establishment of such a custom database is technically complicated and requires a large amount of resources, which most clinical laboratories cannot afford. In this study, we developed a mass spectrum analysis model with 7 mass peak biomarkers for the identification of H. influenzae and H. haemolyticus using the ClinProTools software. We evaluated the diagnostic performance of this model using 408 H. influenzae and H. haemolyticus isolates from clinical respiratory specimens from 363 hospitalized patients and compared the identification results with those obtained with the Bruker IVD MALDI Biotyper. The IVD MALDI Biotyper identified only 86.9% of H. influenzae (311/358) and 98.0% of H. haemolyticus (49/50) clinical isolates to the species level. In comparison, the ClinProTools mass spectrum model could identify 100% of H. influenzae (358/358) and H. haemolyticus (50/50) clinical strains to the species level and significantly improved the species identification rate (McNemar's test, P mass spectrometry to handle closely related bacterial species when the proprietary spectrum library failed. This approach should be useful for the differentiation of other closely related bacterial species. Copyright © 2017 American Society for Microbiology.

  13. Pharmacokinetics/Pharmacodynamics of Peptide Deformylase Inhibitor GSK1322322 against Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus in Rodent Models of Infection.

    Science.gov (United States)

    Hoover, Jennifer; Lewandowski, Thomas; Straub, Robert J; Novick, Steven J; DeMarsh, Peter; Aubart, Kelly; Rittenhouse, Stephen; Zalacain, Magdalena

    2015-10-19

    GSK1322322 is a novel inhibitor of peptide deformylase (PDF) with good in vitro activity against bacteria associated with community-acquired pneumonia and skin infections. We have characterized the in vivo pharmacodynamics (PD) of GSK1322322 in immunocompetent animal models of infection with Streptococcus pneumoniae and Haemophilus influenzae (mouse lung model) and with Staphylococcus aureus (rat abscess model) and determined the pharmacokinetic (PK)/PD index that best correlates with efficacy and its magnitude. Oral PK studies with both models showed slightly higher-than-dose-proportional exposure, with 3-fold increases in area under the concentration-time curve (AUC) with doubling doses. GSK1322322 exhibited dose-dependent in vivo efficacy against multiple isolates of S. pneumoniae, H. influenzae, and S. aureus. Dose fractionation studies with two S. pneumoniae and S. aureus isolates showed that therapeutic outcome correlated best with the free AUC/MIC (fAUC/MIC) index in S. pneumoniae (R(2), 0.83), whereas fAUC/MIC and free maximum drug concentration (fCmax)/MIC were the best efficacy predictors for S. aureus (R(2), 0.9 and 0.91, respectively). Median daily fAUC/MIC values required for stasis and for a 1-log10 reduction in bacterial burden were 8.1 and 14.4 for 11 S. pneumoniae isolates (R(2), 0.62) and 7.2 and 13.0 for five H. influenzae isolates (R(2), 0.93). The data showed that for eight S. aureus isolates, fAUC correlated better with efficacy than fAUC/MIC (R(2), 0.91 and 0.76, respectively), as efficacious AUCs were similar for all isolates, independent of their GSK1322322 MIC (range, 0.5 to 4 μg/ml). Median fAUCs of 2.1 and 6.3 μg · h/ml were associated with stasis and 1-log10 reductions, respectively, for S. aureus. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  14. Erythromycin and azithromycin transport into Haemophilus influenzae ATCC 19418 under conditions of depressed proton motive force (delta mu H)

    Energy Technology Data Exchange (ETDEWEB)

    Capobianco, J.O.; Goldman, R.C. (Abbott Laboratories, IL (USA))

    1990-09-01

    The effect of collapsing the electrochemical proton gradient (delta mu H) on ({sup 3}H)erythromycin and ({sup 14}C)azithromycin transport in Haemophilus influenzae ATCC 19418 was studied. The proton gradient and membrane potential were determined from the distribution of (2-{sup 14}C)dimethadione and rubidium-86, respectively. delta mu H was reduced from 124 to 3 mV in EDTA-valinomycin-treated cells at 22{degrees}C with 150 mM KCl and 0.1 mM carbonyl cyanide m-chlorophenylhydrazone. During the collapse of delta mu H, macrolide uptake increased. Erythromycin efflux studies strongly suggested that this increase was not due to an energy-dependent efflux pump but was likely due to increased outer membrane permeability. These data indicated that macrolide entry was not a delta mu H-driven active transport process but rather a passive diffusion process.

  15. Immunogenicity and thermal stability of a combined vaccine against Haemophilus influenzae type b and Neisseria meningitidis serogroup C diseases.

    Science.gov (United States)

    Saydam, Manolya; Burkin, Karena; Care, Rory; Rigsby, Peter; Bolgiano, Barbara; Mawas, Fatme

    2010-08-31

    The immunogenicity, structure and stability of a combined conjugate vaccine against Haemophilus influenzae type b and meningococcal serogroup C (Hib/MenC) were investigated. A rat model for immunogenicity showed that antibody responses to Hib and MenC in the combined vaccine were similar to or higher than those of individual conjugates given alone, or concomitantly at separate sites. At elevated temperatures, the combination vaccine was slightly more stable than a monovalent Hib-TT vaccine, with respect to molecular size, which could be attributed to differences in the formulations. Following 5 weeks incubation at 56 degrees C, there was some dissociation of high molecular weight conjugate without significant loss of saccharide integrity; however, this did not significantly affect the vaccine immunogenicity, demonstrating the stability of this lyophilized vaccine. (c) 2010 Elsevier Ltd. All rights reserved.

  16. International collaborative study for establishment of the 2nd WHO International Standard for Haemophilus influenzae type b polysaccharide.

    Science.gov (United States)

    Mawas, Fatme; Burkin, Karena; Dougall, Thomas; Saydam, Manolya; Rigsby, Peter; Bolgiano, Barbara

    2015-11-01

    In this report we present the results of a collaborative study for the preparation and calibration of a replacement International Standard (IS) for Haemophilus influenzae type b polysaccharide (polyribosyl ribitol phosphate; 5-d-ribitol-(1 → 1)-β-d-ribose-3-phosphate; PRP). Two candidate preparations were evaluated. Thirteen laboratories from 9 different countries participated in the collaborative study to assess the suitability and determine the PRP content of two candidate standards. On the basis of the results from this study, Candidate 2 (NIBSC code 12/306) has been established as the 2nd WHO IS for PRP by the Expert Committee of Biological Standards of the World Health Organisation with a content of 4.904 ± 0.185mg/ampoule, as determined by the ribose assays carried out by 11 of the participating laboratories. Copyright © 2015 The International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

  17. Antimicrobial activity of innate immune molecules against Streptococcus pneumoniae, Moraxella catarrhalis and nontypeable Haemophilus influenzae

    Directory of Open Access Journals (Sweden)

    Teufert Karen

    2004-05-01

    Full Text Available Abstract Background Despite its direct connection to the nasopharynx which harbors otitis media pathogens as part of its normal flora, the middle ear cavity is kept free of these bacteria by as yet unknown mechanisms. Respiratory mucosal epithelia, including those of the middle ear and eustachian tube, secrete antimicrobial effectors including lysozyme, lactoferrin and β defensins-1 and -2. To elucidate the role of these innate immune molecules in the normal defense and maintenance of sterility of respiratory mucosa such as that of the middle ear, we assessed their effect on the respiratory pathogens nontypeable Haemophilus influenzae (NTHi 12, Moraxella catarrhalis 035E, and Streptococcus pneumoniae 3, and 6B. Methods Two assay methods, the radial assay and the liquid broth assay, were employed for testing the antimicrobial activity of the molecules. This was done in order to minimize the possibility that the observed effects were artifacts of any single assay system employed. Also, transmission electron microscopy (TEM was employed to evaluate the effect of antimicrobial innate immune molecules on OM pathogens. For the statistical analysis of the data, Student's t-test was performed. Results Results of the radial diffusion assay showed that β defensin-2 was active against all four OM pathogens tested, while treatment with β defensin-1 appeared to only affect M. catarrhalis. The radial assay results also showed that lysozyme was quite effective against S. pneumoniae 3 and 6B and was partially bacteriostatic/bactericidal against M. catarrhalis. Lysozyme however, appeared not to affect the growth of NTHi. Thus, lysozyme seems to have a more pronounced impact on the growth of the Gram-positive S. pneumoniae as compared to that of Gram-negative pathogens. Lactoferrin on the other hand, enhanced the growth of the bacteria tested. The results of the radial assays were confirmed using liquid broth assays for antimicrobial activity, and showed that

  18. Vigilancia de los serotipos y susceptibilidad antimicrobiana de Haemophilus influenzae en Colombia, 1994-2002.

    Directory of Open Access Journals (Sweden)

    María Victoria Ovalle

    2003-06-01

    Full Text Available La enfermedad invasora causada por Haemophilus influenzae, serotipo b, ha sido una de las mayores causas de morbilidad y mortalidad en la población infantil; afortunadamente, en algunos países con amplia cobertura de la vacuna conjugada esta situación ha cambiado. En 1994 se inició en el Grupo de Microbiología un programa de vigilancia de la susceptibilidad antimicrobiana y de los serotipos de aislamientos invasores de H. influenzae, remitidos por los hospitales y Laboratorios de Salud Pública del país como componente de los programas de vigilancia en red de infección respiratoria aguda y meningitis bacteriana aguda. El objetivo de este trabajo fue determinar la evolución de los serotipos y los patrones de susceptibilidad antimicrobiana de los aislamientos invasores de H. influenzae obtenidos de 1994 al 2002 y realizar un nuevo análisis sobre el impacto de la vacuna conjugada de H. influenzae, serotipo b, en Colombia. De 1994 a 2002 se han estudiado 683 aislamientos; 379 (55,5% de pacientes del género masculino; 370 (54,2% de menores de 1 año; 227 (33,2% de 1 a 5 años; 19 (2,8% de 6 a 14 años; 38 (5,6% de mayores de 14 años, y de 29 (4,2% no se tenía el dato de la edad; 493 (72,2% fueron recuperados de pacientes con meningitis, 181 (26,5% de neumonía y 9 (0,9% de otras enfermedades. El 85,1% de los aislamientos fueron H. influenzae, serotipo b, 12,9% no capsulares y 2,0% de otros serotipos (10 a, 1 d, 1 e y 2 f. Del total de aislamientos, 12% fueron productores de beta-lactamasa; 13,9%, resistentes a ampicilina; 12,7%, a trimetoprim sulfametoxazol (SXT; 5,4%, a cloranfenicol, y 1% a cefuroxima; todos fueron sensibles a ceftriaxona. Durante este período se observó un incremento en la resistencia de los aislamientos a SXT (5% al 13%, pero la diferencia no fue estadísticamente significativa (p=0,1. Con la vigilancia se pudo determinar una disminución significativa de los casos de meningitis en los menores de 1 año y en el

  19. Case of invasive nontypable Haemophilus influenzae respiratory tract infection with a large quantity of neutrophil extracellular traps in sputum

    Directory of Open Access Journals (Sweden)

    Hamaguchi S

    2012-12-01

    Full Text Available Shigeto Hamaguchi,1,* Masafumi Seki,1,* Norihisa Yamamoto,1 Tomoya Hirose,2 Naoya Matsumoto,2 Taro Irisawa,2 Ryosuke Takegawa,2 Takeshi Shimazu,2 Kazunori Tomono11Division of Infection Control and Prevention, 2Department of Traumatology and Acute Critical Medicine, Osaka University Graduate School of Medicine, Osaka, Japan *These authors contributed equally to this workAbstract: Haemophilus influenzae type b was once the most common cause of invasive H. influenzae infection, but the incidence of this disease has decreased markedly with introduction of conjugate vaccines to prevent the disease. In contrast, the incidence of invasive infection caused by nontypable H. influenzae has increased in the US and in European countries. Neutrophil extracellular traps (NETs are fibrous structures released extracellularly from activated neutrophils during inflammation, including in pneumonia, and rapidly trap and kill pathogens as a first line of immunological defense. However, their function and pathological role have not been fully investigated. Here, we report a case of fatal nontypable H. influenzae infection with severe pneumonia and bacteremia in an adult found to have a vast amount of NETs in his sputum. The patient had a two-day history of common cold-like symptoms and was taken to the emergency room as a cardiopulmonary arrest. He recovered temporarily, but died soon afterwards, although appropriate antibiotic therapy and general management had been instituted. Massive lobular pneumonia and sepsis due to nontypable H. influenzae was found, in spite of H. influenzae type b vaccine being available. His sputum showed numerous bacteria phagocytosed by neutrophils, and immunohistological staining indicated a number of NETs containing DNA, histone H3, and neutrophil elastase. This case highlights an association between formation of NETs and severe respiratory and septic infection. An increase in severe nontypable H. influenzae disease can be expected as a

  20. Cloning and characterization of tdhA, a locus encoding a TonB-dependent heme receptor from Haemophilus ducreyi.

    Science.gov (United States)

    Thomas, C E; Olsen, B; Elkins, C

    1998-09-01

    Haemophilus ducreyi is unable to synthesize heme and must acquire it from its only known host, humans. We cloned and sequenced a gene encoding an outer membrane receptor for heme. It was designated tdhA (for TonB-dependent heme receptor A) since it was related by sequence homology to the family of TonB-dependent receptors. TdhA was strikingly similar to open reading frame HI0113 from the genome of Haemophilus influenzae Rd and also shared homology with five other heme receptors, including HxuC, HemR, HmuR, ChuA, and ShuA, from gram-negative bacteria. An Escherichia coli hemA tonB mutant strongly expressing H. ducreyi tdhA grew on low levels of heme as a source of heme only when an intact H. ducreyi Ton system plasmid was present, formally demonstrating functional TonB dependence. tdhA was expressed poorly in vitro by H. ducreyi and only under conditions of heme limitation. A survey of H. ducreyi revealed that all tested strains but one synthesized small amounts of TdhA in vitro under heme-limiting conditions. Surprisingly, an isogenic mutant of tdhA as well as its parent, 35000, both required the same high levels of heme for growth (50 microgram/ml [77 microM] on agar medium). This result, together with previous findings, suggests that in vitro, the uptake of heme by H. ducreyi is mediated by a TonB- and TdhA-independent mechanism, possibly diffusion.

  1. Carrier state of Haemophilus influenzae type b (Hib, Streptococcus pneumoniae, Streptococcus pyogenes, Neisseria meningitidis and Corynebacterium diphtheriae among school children in Pokhara, Nepal

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    Dharm Raj Bhatta

    2014-02-01

    Full Text Available Objective: To determine the incidence of carrier state of Haemophilus influenzae type b, Streptococcus pneumoniae (S. pneumoniae, Streptococcus pyogenes, Neisseria meningitidis and Corynebacterium diphtheriae among school children. Methods: Specimen from posterior pharyngeal wall and tonsils were collected on calcium alginate coated swabs from 1 02 participants. Processing of specimen and antimicrobial susceptibility testing was done by standard procedures. Results: Potential pathogens isolated in our study were S. pneumoniae (14.7%, Staphylococcus aureus (12.7%, Corynebacterium diphtheriae (3.9%, Streptococcus pyogenes (3.9% and Haemophilus influenzae (1.9%. Important findings in antibiogram include high resistance of S. pneumoniae to penicillin (73% and resistance of Staphylococcus aureus to oxacillin (23%. Conclusions: Pharyngeal colonization by S. pneumoniae among school children was found high and there is need of introduction of pneumococcal vaccines among children. Despite expected universal vaccination, pharyngeal colonization by Corynebacterium diphtheriae is possible and there is possibility of transmission.

  2. Diminished ICAM-1 Expression and Impaired Pulmonary Clearance of Nontypeable Haemophilus influenzae in a Mouse Model of Chronic Obstructive Pulmonary Disease/Emphysema▿

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    Pang, Bing; Hong, Wenzhou; West-Barnette, Shayla L.; Kock, Nancy D.; Swords, W. Edward

    2008-01-01

    The airways of patients with chronic obstructive pulmonary disease (COPD) are continually colonized with bacterial opportunists like nontypeable Haemophilus influenzae (NTHi), and a wealth of evidence indicates that changes in bacterial populations within the lung can influence the severity of COPD. In this study, we used a murine model for COPD/emphysema to test the hypothesis that COPD affects pulmonary clearance. Mice were treated with a pulmonary bolus of elastase, and as reported previou...

  3. Haemophilus influenzae oral vaccination for preventing acute exacerbations of chronic bronchitis and chronic obstructive pulmonary disease.

    Science.gov (United States)

    Teo, Edward; Lockhart, Kathleen; Purchuri, Sai Navya; Pushparajah, Jennifer; Cripps, Allan W; van Driel, Mieke L

    2017-06-19

    Chronic bronchitis and chronic obstructive pulmonary disease (COPD) are serious conditions in which patients are predisposed to viral and bacterial infections resulting in potentially fatal acute exacerbations. Chronic obstructive pulmonary disease is defined as a lung disease characterised by obstruction to lung airflow that interferes with normal breathing. Antibiotic therapy has not been particularly useful in eradicating bacteria such as non-typeable Haemophilus influenzae (NTHi) because they are naturally occurring flora of the upper respiratory tract in many people. However, they can cause opportunistic infection. An oral NTHi vaccine has been developed to protect against recurrent infective acute exacerbations in chronic bronchitis. To assess the effectiveness of an oral, whole-cell NTHi vaccine in protecting against recurrent episodes of acute exacerbations of chronic bronchitis and COPD in adults. To assess the effectiveness of NTHi vaccine in reducing NTHi colonising the respiratory tract during recurrent episodes of acute exacerbations of COPD. We searched the following databases: the Cochrane Central Register of Controlled Trials (CENTRAL) (2017, Issue 1), MEDLINE (1946 to January 2017), Embase (1974 to January 2017), CINAHL (1981 to January 2017), LILACS (1985 to January 2017), and Web of Science (1955 to January 2017). We also searched trials registries and contacted authors of trials requesting unpublished data. We included randomised controlled trials comparing the effects of an oral monobacterial NTHi vaccine in adults with recurrent acute exacerbations of chronic bronchitis or COPD when there was overt matching of the vaccine and placebo groups on clinical grounds. The selection criteria considered populations aged less than 65 years and those older than 65 years. Two review authors independently assessed trial quality and extracted data from original records and publications for incidence and severity of bronchitis episodes and carriage rate of

  4. Oropharyngeal colonization by Haemophilus influenzae in healthy children from Taubaté (São Paulo, prior to the Haemophilus influenzae type b vaccination program in Brazil Colonização da orofaringe de crianças saudáveis de Taubaté (São Paulo por Haemophilus influenzae, antes da introdução da vacina contra Haemophilus influenzae do tipo b no Brasil

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    Lucia Ferro Bricks

    2004-01-01

    Full Text Available Haemophilus influenzae is one of the most important bacterial agents of otitis and sinusitis. H. influenzae type b (Hib is one of the main causes of meningitis, pneumonia, and septicemia in nonvaccinated children under 6 years of age. The aims of this study were to determine the prevalence of H. influenzae and Hib oropharyngeal colonization prior to the onset of the Hib vaccination program in Brazil in previously healthy children and to assess the susceptibility profile of this microorganism to a selected group of antimicrobials that are used to treat acute respiratory infections. METHOD: Cultures of Haemophilus influenzae were made from oropharynx swabs from 987 children under 6 years of age who were enrolled in 29 day-care centers in Taubaté (a city of São Paulo state, Brazil between July and December 1998. RESULTS: The prevalence of H. influenzae carriers was 17.4%, and only 5.5% of the strains were beta-lactamase producers. The prevalence of Hib carriers was high, 7.3% on average (range, 0.0 - 33.3%. CONCLUSIONS: The low prevalence of colonization by penicillin-resistant strains indicates that it is not necessary to substitute ampicilin or amoxicilin to effectively treat otitis and sinusitis caused by H. influenzae in Taubaté.Haemophilus influenzae é um dos mais importantes agentes bacterianos de otites e sinusites. Em crianças menores de seis anos de idade não vacinadas contra o H. influenzae do tipo b (Hib, essa bactéria é uma das principais causadoras de meningite, pneumonia e sepse. O objetivo deste estudo foi determinar a prevalência da colonização da orofaringe de crianças previamente saudáveis por H. influenzae e Hib e avaliar o perfil de suscetibilidade desses microorganismos a um grupo seleto de antimicrobianos, que habitualmente são utilizados para tratar as infecções respiratórias agudas. MÉTODO: Foram colhidos swabs da orofaringe de 987 crianças menores de seis anos de idade que freqüentavam 29 creches da

  5. Sialic acid mediated transcriptional modulation of a highly conserved sialometabolism gene cluster in Haemophilus influenzae and its effect on virulence

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    Moxon Richard

    2010-02-01

    Full Text Available Abstract Background Sialic acid has been shown to be a major virulence determinant in the pathogenesis of otitis media caused by the bacterium Haemophilus influenzae. This study aimed to characterise the expression of genes required for the metabolism of sialic acid and to investigate the role of these genes in virulence. Results Using qRT-PCR, we observed decreased transcriptional activity of genes within a cluster that are required for uptake and catabolism of 5-acetyl neuraminic acid (Neu5Ac, when bacteria were cultured in the presence of the sugar. We show that these uptake and catabolic genes, including a sialic acid regulatory gene (siaR, are highly conserved in the H. influenzae natural population. Mutant strains were constructed for seven of the nine genes and their influence upon LPS sialylation and resistance of the bacteria to the killing effect of normal human serum were assessed. Mutations in the Neu5Ac uptake (TRAP transporter genes decreased virulence in the chinchilla model of otitis media, but the attenuation was strain dependent. In contrast, mutations in catabolism genes and genes regulating sialic acid metabolism (siaR and crp did not attenuate virulence. Conclusion The commensal and pathogenic behaviour of H. influenzae involves LPS sialylation that can be influenced by a complex regulatory interplay of sialometabolism genes.

  6. Investigations into genome diversity of Haemophilus influenzae using whole genome sequencing of clinical isolates and laboratory transformants.

    Science.gov (United States)

    Power, Peter M; Bentley, Stephen D; Parkhill, Julian; Moxon, E Richard; Hood, Derek W

    2012-11-23

    Haemophilus influenzae is an important human commensal pathogen associated with significant levels of disease. High-throughput DNA sequencing was used to investigate differences in genome content within this species. Genomic DNA sequence was obtained from 85 strains of H. influenzae and from other related species, selected based on geographical site of isolation, disease association and documented genotypic and phenotypic differences. When compared by Mauve alignment these indicated groupings of H. influenzae that were consistent with previously published analyses; capsule expressing strains fell into two distinct groups and those of serotype b (Hib) were found in two closely positioned lineages. For 18 Hib strains representing both lineages we found many discrete regions (up to 40% of the total genome) displaying sequence variation when compared to a common reference strain. Evidence that this naturally occurring pattern of inter-strain variation in H. influenzae can be mediated by transformation was obtained through sequencing DNA obtained from a pool of 200 independent transformants of a recipient (strain Rd) using donor DNA from a heterologous Hib strain (Eagan). Much of the inter-strain variation in genome sequence in H. influenzae is likely the result of inter-strain exchanges of DNA, most plausibly through transformation.

  7. Outcome of meningitis caused by Streptococcus pneumoniae and Haemophilus influenzae type b in children in The Gambia.

    Science.gov (United States)

    Goetghebuer, T; West, T E; Wermenbol, V; Cadbury, A L; Milligan, P; Lloyd-Evans, N; Adegbola, R A; Mulholland, E K; Greenwood, B M; Weber, M W

    2000-03-01

    In developing countries, endemic childhood meningitis is a severe disease caused most commonly by Streptococcus pneumoniae or Haemophilus influenzae type b (Hib). Although many studies have shown that fatality rates associated with meningitis caused by these organisms are high in developing countries, little is known about the long-term outcome of survivors. The purpose of this study was to assess the importance of disabilities following pneumococcal and Hib meningitis in The Gambia. 257 children aged 0-12 years hospitalized between 1990 and 1995 with culture-proven S. pneumoniae (n = 134) or Hib (n = 123) meningitis were included retrospectively in the study. 48% of children with pneumococcal meningitis and 27% of children with Hib meningitis died whilst in hospital. Of the 160 survivors, 89 (55%) were followed up between September 1996 and October 1997. Of the children with pneumococcal meningitis that were traced, 58% had clinical sequelae; half of them had major disabilities preventing normal adaptation to social life. 38% of survivors of Hib meningitis had clinical sequelae, a quarter of whom had major disabilities. Major handicaps found were hearing loss, mental retardation, motor abnormalities and seizures. These data show that despite treatment with effective antibiotics, pneumococcal and Hib meningitis kill many Gambian children and leave many survivors with severe sequelae. Hib vaccination is now given routinely in The Gambia; an effective pneumococcal vaccine is needed.

  8. Emergence of Non-Serotype b Encapsulated Haemophilus influenzae as a Cause of Pediatric Meningitis in Northwestern Ontario

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    Pouya Sadeghi-Aval

    2013-01-01

    Full Text Available Before the introduction of the conjugate vaccine, Haemophilus influenzae serotype b (Hib was the leading cause of bacterial meningitis in children. Although successful in reducing Hib cases, the vaccine confers no protection against other serotypes of H influenzae, such as a (Hia, or f (Hif. The emergence of invasive disease caused by non-Hib in northwestern Ontario (38 cases between 2002 and 2008 with predominance of Hia was previously reported by the authors. At that time, no cases of pediatric meningitis caused by H influenzae were recorded in the region. Continued surveillance identified 12 new cases of invasive non-Hib between January 2009 and July 2011. Among these cases, three young children developed meningitis with severe complications caused by Hia or Hif. The present article describes these cases along with the characteristics of recent H influenzae isolates from the region, (ie, their genetic background and antibiotic sensitivity. The findings point to the clonal nature of circulating Hia strains as well as to an increase in frequency and severity of pediatric invasive H influenzae infections in northwestern Ontario.

  9. [Activity of cefpodoxime and other oral beta-lactams against Haemophilus influenzae and Streptococcus pneumoniae with different susceptibilities to penicillin].

    Science.gov (United States)

    Fenoll, A; Robledo, O; Lerma, M; Giménez, M J; Cebrián, L; Casal, J; Aguilar, L; Gómez-Lus, M L

    2006-03-01

    This study explores the influence on the intrinsic activity of different oral beta-lactams of beta-lactamase production in Haemophilus influenzae and penicillin resistance in Streptococcus pneumoniae. Three substudies were performed: a) a general susceptibility study, analyzing 550 strains received by the Spanish Laboratorio de Referencia de Neumococos throughout February and March 2005; b) a study on the influence of penicillin resistance on the activity of beta-lactams, analyzing 251 penicillin-susceptible strains (MICor=2 mg/l) randomly chosen among those received by the Spanish Laboratorio de Referencia de Neumococos throughout 2005; and c) an H. influenzae susceptibility study analyzing 150 strains received by Instituto Valenciano de Microbiologia throughout 2005. A total of 71% of S. pneumoniae strains were susceptible to penicillin, 21% exhibited intermediate resistance and 8% strains presented full resistance. H. influenzae beta-lactamase production rate was 18.6%. Of the non-beta-lactamase-producing strains, 3% were not susceptible to ampicillin. Cefpodoxime and cefixime exhibited the highest intrinsic activity against H. influenzae, while amoxicillin and cefpodoxime were the most active compounds against S. pneumoniae. All H. influenzae strains were susceptible to oral cephalosporins and amoxicillin/clavulanic acid. The increase in penicillin resistance in S. pneumoniae influenced cefixime, cefaclor and cefuroxime to a higher degree than amoxicillin and cefpodoxime.

  10. Coupling of NAD+ biosynthesis and nicotinamide ribosyl transport: characterization of NadR ribonucleotide kinase mutants of Haemophilus influenzae.

    Science.gov (United States)

    Merdanovic, Melisa; Sauer, Elizabeta; Reidl, Joachim

    2005-07-01

    Previously, we characterized a pathway necessary for the processing of NAD+ and for uptake of nicotinamide riboside (NR) in Haemophilus influenzae. Here we report on the role of NadR, which is essential for NAD+ utilization in this organism. Different NadR variants with a deleted ribonucleotide kinase domain or with a single amino acid change were characterized in vitro and in vivo with respect to cell viability, ribonucleotide kinase activity, and NR transport. The ribonucleotide kinase mutants were viable only in a nadV+ (nicotinamide phosphoribosyltransferase) background, indicating that the ribonucleotide kinase domain is essential for cell viability in H. influenzae. Mutations located in the Walker A and B motifs and the LID region resulted in deficiencies in both NR phosphorylation and NR uptake. The ribonucleotide kinase function of NadR was found to be feedback controlled by NAD+ under in vitro conditions and by NAD+ utilization in vivo. Taken together, our data demonstrate that the NR phosphorylation step is essential for both NR uptake across the inner membrane and NAD+ synthesis and is also involved in controlling the NAD+ biosynthesis rate.

  11. Patients with chronic obstructive pulmonary disease and chronically colonized with Haemophilus influenzae during stable disease phase have increased airway inflammation.

    Science.gov (United States)

    Tufvesson, Ellen; Bjermer, Leif; Ekberg, Marie

    2015-01-01

    Some patients with chronic obstructive pulmonary disease (COPD) show increased airway inflammation and bacterial colonization during stable phase. The aim of this study was to follow COPD patients and investigate chronic colonization with pathogenic bacteria during stable disease phase, and relate these findings to clinical parameters, inflammatory pattern, lung function, and exacerbations. Forty-three patients with COPD were included while in a stable state and followed up monthly until exacerbation or for a maximum of 6 months. The patients completed the Clinical COPD Questionnaire and Medical Research Council dyspnea scale questionnaires, and exhaled breath condensate was collected, followed by spirometry, impulse oscillometry, and sputum induction. Ten patients were chronically colonized (ie, colonized at all visits) with Haemophilus influenzae during stable phase. These patients had higher sputum levels of leukotriene B4 (Pchronically colonized patients. The difference in airway inflammation seen during stable phase in patients chronically colonized with H. influenzae was not observed during exacerbations. Some COPD patients who were chronically colonized with H. influenzae during stable phase showed increased airway inflammation and reduced lung volumes when compared with non-chronically colonized patients.

  12. Accelerating introduction of new vaccines: barriers to introduction and lessons learned from the recent Haemophilus influenzae type B vaccine experience.

    Science.gov (United States)

    Hajjeh, Rana

    2011-10-12

    Adoption of new vaccines in developing countries is critical to reducing child mortality and meeting Millennium Development Goal 4. However, such introduction has historically suffered from significant delays that can be attributed to various factors including (i) lack of recognition of the value of a vaccine, (ii) factors related to weak health systems, and (iii) policy considerations. Recently, the Global Alliance for Vaccines and Immunization (GAVI) supported efforts to accelerate the introduction of Haemophilus influenzae type b (Hib) vaccines in developing countries, which resulted in a significant surge in vaccine adoption by these countries. The experience with Hib vaccines, as well as similar efforts by GAVI to support the introduction of new pneumococcal and rotavirus vaccines, provides a strategy for new vaccine adoption that is reviewed in this paper, providing a useful model to help accelerate the uptake of other life-saving vaccines. This strategy addresses barriers for vaccine adoption by focusing on three major areas: (i) communications to increase awareness about the various factors needed for evidence-based decisions that meet a country's health goals; (ii) research activities to answer key questions that support vaccine introduction and long-term programme sustainability; and (iii) coordination with the various stakeholders at global, regional and country levels to ensure successful programme implementation.

  13. A glycoconjugate of Haemophilus influenzae Type b capsular polysaccharide with tetanus toxoid protein: hydrodynamic properties mainly influenced by the carbohydrate

    Science.gov (United States)

    Abdelhameed, Ali Saber; Adams, Gary G.; Morris, Gordon A.; Almutairi, Fahad M.; Duvivier, Pierre; Conrath, Karel; Harding, Stephen E.

    2016-01-01

    Three important physical properties which may affect the performance of glycoconjugate vaccines against serious disease are molar mass (molecular weight), heterogeneity (polydispersity), and conformational flexibility in solution. The dilute solution behaviour of native and activated capsular polyribosylribitol (PRP) polysaccharides extracted from Haemophilus influenzae type b (Hib), and the corresponding glycoconjugate made by conjugating this with the tetanus toxoid (TT) protein have been characterized and compared using a combination of sedimentation equilibrium and sedimentation velocity in the analytical ultracentrifuge with viscometry. The weight average molar mass of the activated material was considerably reduced (Mw ~ 0.24 × 106 g.mol−1) compared to the native (Mw ~ 1.2 × 106 g.mol−1). Conjugation with the TT protein yielded large polydisperse structures (of Mw ~ 7.4 × 106 g.mol−1), but which retained the high degree of flexibility of the native and activated polysaccharide, with frictional ratio, intrinsic viscosity, sedimentation conformation zoning behaviour and persistence length all commensurate with highly flexible coil behaviour and unlike the previously characterised tetanus toxoid protein (slightly extended and hydrodynamically compact structure with an aspect ratio of ~3). This non-protein like behaviour clearly indicates that it is the carbohydrate component which mainly influences the physical behaviour of the glycoconjugate in solution. PMID:26915577

  14. Mapping the Laminin Receptor Binding Domains of Neisseria meningitidis PorA and Haemophilus influenzae OmpP2

    Science.gov (United States)

    Mahdavi, Jafar; Oldfield, Neil J.; Wheldon, Lee M.; Wooldridge, Karl G.; Ala'Aldeen, Dlawer A. A.

    2012-01-01

    Neisseria meningitidis, Haemophilus influenzae and Streptococcus pneumoniae are major bacterial agents of meningitis. They each bind the 37/67-kDa laminin receptor (LamR) via the surface protein adhesins: meningococcal PilQ and PorA, H. influenzae OmpP2 and pneumococcal CbpA. We have previously reported that a surface-exposed loop of the R2 domain of CbpA mediates LamR-binding. Here we have identified the LamR-binding regions of PorA and OmpP2. Using truncated recombinant proteins we show that binding is dependent on amino acids 171–240 and 91–99 of PorA and OmpP2, respectively, which are predicted to localize to the fourth and second surface-exposed loops, respectively, of these proteins. Synthetic peptides corresponding to the loops bound LamR and could block LamR-binding to bacterial ligands in a dose dependant manner. Meningococci expressing PorA lacking the apex of loop 4 and H. influenzae expressing OmpP2 lacking the apex of loop 2 showed significantly reduced LamR binding. Since both loops are hyper-variable, our data may suggest a molecular basis for the range of LamR-binding capabilities previously reported among different meningococcal and H. influenzae strains. PMID:23049988

  15. Two Glycosyltransferase Genes of Haemophilus parasuis SC096 Implicated in Lipo-oligosaccharide Biosynthesis, Serum Resistance, Adherence and Invasion

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    Qi Zhou

    2016-09-01

    Full Text Available Haemophilus parasuis is a common opportunistic pathogen known for its ability to colonize healthy piglets and causes Glässer’s disease. The lipooligosaccharide (LOS of H. parasuis is a potential virulence-associated factor. In this study, two putative glycosyltransferases that might be involved in LOS synthesis in H. parasuis SC096 were identified (lgtB and lex-1. Mutants were constructed to investigate the roles of the lgtB and lex-1 genes. The LOS from the ΔlgtB or Δlex-1 mutant showed truncated structure on silver-stained SDS-PAGE gel compared to the wild-type strain. The ΔlgtB and Δlex-1 mutants were significantly more sensitive to 50% porcine serum, displaying 15.0% and 54.46% survival rates, respectively. Complementation of the lex-1 mutant restored the serum-resistant phenotype. Additionally, the ΔlgtB and Δlex-1 strains showed impaired ability to adhere to and invade porcine kidney epithelial cells (PK-15. The above results suggested that the lgtB and lex-1 genes of the H. parasuis SC096 strain participated in LOS synthesis and were involved in serum resistance, adhesion and invasion.

  16. Quantitative fucK gene polymerase chain reaction on sputum and nasopharyngeal secretions to detect Haemophilus influenzae pneumonia.

    Science.gov (United States)

    Abdeldaim, Guma M K; Strålin, Kristoffer; Olcén, Per; Blomberg, Jonas; Mölling, Paula; Herrmann, Björn

    2013-06-01

    A quantitative polymerase chain reaction (PCR) for the fucK gene was developed for specific detection of Haemophilus influenzae. The method was tested on sputum and nasopharyngeal aspirate (NPA) from 78 patients with community-acquired pneumonia (CAP). With a reference standard of sputum culture and/or serology against the patient's own nasopharyngeal isolate, H. influenzae etiology was detected in 20 patients. Compared with the reference standard, fucK PCR (using the detection limit 10(5) DNA copies/mL) on sputum and NPA showed a sensitivity of 95.0% (19/20) in both cases, and specificities of 87.9% (51/58) and 89.5% (52/58), respectively. In a receiver operating characteristic curve analysis, sputum fucK PCR was found to be significantly superior to sputum P6 PCR for detection of H. influenzae CAP. NPA fucK PCR was positive in 3 of 54 adult controls without respiratory symptoms. In conclusion, quantitative fucK real-time PCR provides a sensitive and specific identification of H. influenzae in respiratory secretions. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Immunization with the Haemophilus ducreyi hemoglobin receptor HgbA protects against infection in the swine model of chancroid.

    Science.gov (United States)

    Afonina, Galyna; Leduc, Isabelle; Nepluev, Igor; Jeter, Chrystina; Routh, Patty; Almond, Glen; Orndorff, Paul E; Hobbs, Marcia; Elkins, Christopher

    2006-04-01

    The etiologic agent of chancroid is Haemophilus ducreyi. To fulfill its obligate requirement for heme, H. ducreyi uses two TonB-dependent receptors: the hemoglobin receptor (HgbA) and a receptor for free heme (TdhA). Expression of HgbA is necessary for H. ducreyi to survive and initiate disease in a human model of chancroid. In this study, we used a swine model of H. ducreyi infection to demonstrate that an experimental HgbA vaccine efficiently prevents chancroid, as determined by several parameters. Histological sections of immunized animals lacked typical microscopic features of chancroid. All inoculated sites from mock-immunized pigs yielded viable H. ducreyi cells, whereas no viable H. ducreyi cells were recovered from inoculated sites of HgbA-immunized pigs. Antibodies from sera of HgbA-immunized animals bound to and initiated antibody-dependent bactericidal activity against homologous H. ducreyi strain 35000HP and heterologous strain CIP542 ATCC; however, an isogenic hgbA mutant of 35000HP was not killed, proving specificity. Anti-HgbA immunoglobulin G blocked hemoglobin binding to the HgbA receptor, suggesting a novel mechanism of protection through the limitation of heme/iron acquisition by H. ducreyi. Such a vaccine strategy might be applied to other bacterial pathogens with strict heme/iron requirements. Taken together, these data suggest continuing the development of an HgbA subunit vaccine to prevent chancroid.

  18. Genomic Variability of Haemophilus influenzae Isolated from Mexican Children Determined by Using Enterobacterial Repetitive Intergenic Consensus Sequences and PCR

    Science.gov (United States)

    Gomez-De-Leon, Patricia; Santos, Jose I.; Caballero, Javier; Gomez, Demostenes; Espinosa, Luz E.; Moreno, Isabel; Piñero, Daniel; Cravioto, Alejandro

    2000-01-01

    Genomic fingerprints from 92 capsulated and noncapsulated strains of Haemophilus influenzae from Mexican children with different diseases and healthy carriers were generated by PCR using the enterobacterial repetitive intergenic consensus (ERIC) sequences. A cluster analysis by the unweighted pair-group method with arithmetic averages based on the overall similarity as estimated from the characteristics of the genomic fingerprints, was conducted to group the strains. A total of 69 fingerprint patterns were detected in the H. influenzae strains. Isolates from patients with different diseases were represented by a variety of patterns, which clustered into two major groups. Of the 37 strains isolated from cases of meningitis, 24 shared patterns and were clustered into five groups within a similarity level of 1.0. One fragment of 1.25 kb was common to all meningitis strains. H. influenzae strains from healthy carriers presented fingerprint patterns different from those found in strains from sick children. Isolates from healthy individuals were more variable and were distributed differently from those from patients. The results show that ERIC-PCR provides a powerful tool for the determination of the distinctive pathogenicity potentials of H. influenzae strains and encourage its use for molecular epidemiology investigations. PMID:10878033

  19. Haemophilus influenzae pneumonia in human immunodeficiency virus-infected patients. The Grupo Andaluz para el Estudio de las Enfermedades Infecciosas.

    Science.gov (United States)

    Cordero, E; Pachón, J; Rivero, A; Girón, J A; Gómez-Mateos, J; Merino, M D; Torres-Tortosa, M; González-Serrano, M; Aliaga, L; Collado, A; Hernández-Quero, J; Barrera, A; Nuño, E

    2000-03-01

    Although Haemophilus influenzae is a common etiologic agent of pneumonia in patients infected with human immunodeficiency virus (HIV), the characteristics of this pneumonia have not been adequately assessed. We have prospectively studied features of H. influenzae pneumonia in 26 consecutive HIV-infected inpatients. Most of these patients were severely immunosuppressed; 73.1% had a CD4+ cell count <100/microL. A subacute clinical presentation was observed in 27% of the patients and was associated with a higher degree of immunosuppression (P=.04). Bilateral lung infiltrates were noted radiographically in 57.7% of the cases. The mortality attributable to H. influenzae pneumonia was 11.5%. Thus, pneumonia caused by H. influenzae affects mainly patients with advanced HIV disease, and since its clinical and radiological features may be diverse, this etiology should be considered when pneumonia occurs in patients with advanced HIV infection. The mortality rate associated with H. influenzae pneumonia is not higher than that occurring in the general population.

  20. Density interactions among Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus in the nasopharynx of young Peruvian children.

    Science.gov (United States)

    Chien, Yu-Wen; Vidal, Jorge E; Grijalva, Carlos G; Bozio, Catherine; Edwards, Kathryn M; Williams, John V; Griffin, Marie R; Verastegui, Hector; Hartinger, Stella M; Gil, Ana I; Lanata, Claudio F; Klugman, Keith P

    2013-01-01

    Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus are commonly carried in the nasopharynx of young children, and have been speculated to interact with each other. Although earlier studies used cultures alone to assess these interactions, the addition of real-time quantitative polymerase chain reaction (qPCR) provides further insight into these interactions. We compared results of culture and qPCR for the detection of these 3 bacteria in 446 nasopharynx samples collected from 360 healthy young children in a prospective cohort study in the Peruvian Andes. Patterns of concurrent bacterial colonization were studied using repeated measures logistic regression models with generalized estimating equations. Spearman correlation coefficients were used to assess correlations among bacterial densities. At a bacterial density 10 colony forming units/mL. In addition, there was a positive association between S. pneumoniae and H. influenzae colonization measured by both culture (odds ratio [OR] 3.11-3.17, P Staphylococcus aureus in carriage with both culture (OR 0.45, P = 0.024) and qPCR (OR 0.61, P < 0.05). The impact of density on detection by culture and the observed density-related interactions support use of qPCR in additional studies to examine vaccine effects on diverse bacterial species.

  1. Epidemiological Markers for Interactions Among Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus in Upper Respiratory Tract Carriage.

    Science.gov (United States)

    Lewnard, Joseph A; Givon-Lavi, Noga; Huppert, Amit; Pettigrew, Melinda M; Regev-Yochay, Gili; Dagan, Ron; Weinberger, Daniel M

    2016-05-15

    Cocolonization by Streptococcus pneumoniae and Haemophilus influenzae among children has been noted in numerous studies, as has an inverse relationship involving colonization with these species and Staphylococcus aureus. Interactions among these pathogens could mediate unanticipated outcomes of clinical interventions, including changes in H. influenzae and S. aureus disease incidence following pneumococcal vaccine introduction. However, it remains unclear whether cocolonization patterns represent true interspecies interactions or whether they result from confounding factors. We investigated polymicrobial carriage using longitudinal data from 369 Bedouin children and 400 Jewish children in Israel who were enrolled in a 7-valent pneumococcal conjugate vaccine (PCV7) trial. Children were swabbed 10 times between 2 and 30 months of age. The pathogens followed distinct age and seasonal distributions, but polymicrobial carriage associations persisted after controlling for these and other confounding factors. Receipt of PCV7 resulted in pneumococcal serotype replacement but did not influence total carriage of S. pneumoniae, H. influenzae, or S. aureus. The fact that S. pneumoniae, H. influenzae, and S. aureus polymicrobial carriage patterns do not result from confounding by age and season supports the idea of active interspecies interactions. However, pneumococcal serotype replacement may prevent changes in H. influenzae and S. aureus carriage among PCV7 recipients. © The Author 2015. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  2. Experimental design and metabolic flux analysis tools to optimize industrially relevant Haemophilus influenzae type b growth medium.

    Science.gov (United States)

    da Silva, Mateus Ribeiro; Andreia Freixo Portela, Carla; Maria Ferreira Albani, Silvia; Rizzo de Paiva, Paola; Massako Tanizaki, Martha; Zangirolami, Teresa Cristina

    2017-11-01

    Haemophilus influenzae type b (Hib), a Gram-negative capsulated bacterium, is a causative agent of meningitis worldwide. The capsular polysaccharide, a high molecular mass polymer consisting of the repeated units of the polyribosyl-ribitol-phosphate, is considered the main virulence factor and it is used as an antigen to vaccines, conjugated to a carrier protein. The industrial production of the polysaccharide requires the cultivation of Hib in rich medium, which impacts process costs and product recovery. In this study, a central composite rotational experimental design strategy was used to access the influence of key components of culture medium (soy peptone, yeast extract and glucose) on biomass formation and polysaccharide production in shake-flasks. The optimized medium formulation, containing half of the usual yeast extract and soytone concentrations, was further validated in batch bioreactor cultivations. High polysaccharide production (∼500 mg/L) was obtained in a cheaper and more competitive production process for use in Hib vaccine production. In addition, simulations of a metabolic model describing Hib central metabolism were used to assess the role of key amino acids on growth. A chemically defined medium supplemented only with amino acids from α-ketoglutarate and oxaloacetate families as well as phenylalanine was suggested as a promising alternative for reduced acetate accumulation and enhanced polysaccharide production in Hib cultures. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1508-1519, 2017. © 2017 American Institute of Chemical Engineers.

  3. Mapping the laminin receptor binding domains of Neisseria meningitidis PorA and Haemophilus influenzae OmpP2.

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    Noha M Abouseada

    Full Text Available Neisseria meningitidis, Haemophilus influenzae and Streptococcus pneumoniae are major bacterial agents of meningitis. They each bind the 37/67-kDa laminin receptor (LamR via the surface protein adhesins: meningococcal PilQ and PorA, H. influenzae OmpP2 and pneumococcal CbpA. We have previously reported that a surface-exposed loop of the R2 domain of CbpA mediates LamR-binding. Here we have identified the LamR-binding regions of PorA and OmpP2. Using truncated recombinant proteins we show that binding is dependent on amino acids 171-240 and 91-99 of PorA and OmpP2, respectively, which are predicted to localize to the fourth and second surface-exposed loops, respectively, of these proteins. Synthetic peptides corresponding to the loops bound LamR and could block LamR-binding to bacterial ligands in a dose dependant manner. Meningococci expressing PorA lacking the apex of loop 4 and H. influenzae expressing OmpP2 lacking the apex of loop 2 showed significantly reduced LamR binding. Since both loops are hyper-variable, our data may suggest a molecular basis for the range of LamR-binding capabilities previously reported among different meningococcal and H. influenzae strains.

  4. Mapping the laminin receptor binding domains of Neisseria meningitidis PorA and Haemophilus influenzae OmpP2.

    Science.gov (United States)

    Abouseada, Noha M; Assafi, Mahde Saleh A; Mahdavi, Jafar; Oldfield, Neil J; Wheldon, Lee M; Wooldridge, Karl G; Ala'Aldeen, Dlawer A A

    2012-01-01

    Neisseria meningitidis, Haemophilus influenzae and Streptococcus pneumoniae are major bacterial agents of meningitis. They each bind the 37/67-kDa laminin receptor (LamR) via the surface protein adhesins: meningococcal PilQ and PorA, H. influenzae OmpP2 and pneumococcal CbpA. We have previously reported that a surface-exposed loop of the R2 domain of CbpA mediates LamR-binding. Here we have identified the LamR-binding regions of PorA and OmpP2. Using truncated recombinant proteins we show that binding is dependent on amino acids 171-240 and 91-99 of PorA and OmpP2, respectively, which are predicted to localize to the fourth and second surface-exposed loops, respectively, of these proteins. Synthetic peptides corresponding to the loops bound LamR and could block LamR-binding to bacterial ligands in a dose dependant manner. Meningococci expressing PorA lacking the apex of loop 4 and H. influenzae expressing OmpP2 lacking the apex of loop 2 showed significantly reduced LamR binding. Since both loops are hyper-variable, our data may suggest a molecular basis for the range of LamR-binding capabilities previously reported among different meningococcal and H. influenzae strains.

  5. Nonencapsulated Streptococcus pneumoniae causes otitis media during single-species infection and during polymicrobial infection with nontypeable Haemophilus influenzae.

    Science.gov (United States)

    Murrah, Kyle A; Pang, Bing; Richardson, Stephen; Perez, Antonia; Reimche, Jennifer; King, Lauren; Wren, John; Swords, W Edward

    2015-07-01

    Streptococcus pneumoniae strains lacking capsular polysaccharide have been increasingly reported in carriage and disease contexts. Since most cases of otitis media involve more than one bacterial species, we aimed to determine the capacity of a nonencapsulated S. pneumoniae clinical isolate to induce disease in the context of a single-species infection and as a polymicrobial infection with nontypeable Haemophilus influenzae. Using the chinchilla model of otitis media, we found that nonencapsulated S. pneumoniae colonizes the nasopharynx following intranasal inoculation, but does not readily ascend into the middle ear. However, when we inoculated nonencapsulated S. pneumoniae directly into the middle ear, the bacteria persisted for two weeks post-inoculation and induced symptoms consistent with chronic otitis media. During coinfection with nontypeable H. influenzae, both species persisted for one week and induced polymicrobial otitis media. We also observed that nontypeable H. influenzae conferred passive protection from killing by amoxicillin upon S. pneumoniae from within polymicrobial biofilms in vitro. Therefore, based on these results, we conclude that nonencapsulated pneumococci are a potential causative agent of chronic/recurrent otitis media, and can also cause mutualistic infection with other opportunists, which could complicate treatment outcomes. © FEMS 2014. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Indirect pathogenicity of Haemophilus influenzae and Moraxella catarrhalis in polymicrobial otitis media occurs via interspecies quorum signaling.

    Science.gov (United States)

    Armbruster, Chelsie E; Hong, Wenzhou; Pang, Bing; Weimer, Kristin E D; Juneau, Richard A; Turner, James; Swords, W Edward

    2010-07-06

    Otitis media (OM) is among the leading diseases of childhood and is caused by opportunists that reside within the nasopharynx, such as Haemophilus influenzae and Moraxella catarrhalis. As with most airway infections, it is now clear that OM infections involve multiple organisms. This study addresses the hypothesis that polymicrobial infection alters the course, severity, and/or treatability of OM disease. The results clearly show that coinfection with H. influenzae and M. catarrhalis promotes the increased resistance of biofilms to antibiotics and host clearance. Using H. influenzae mutants with known biofilm defects, these phenotypes were shown to relate to biofilm maturation and autoinducer-2 (AI-2) quorum signaling. In support of the latter mechanism, chemically synthesized AI-2 (dihydroxypentanedione [DPD]) promoted increased M. catarrhalis biofilm formation and resistance to antibiotics. In the chinchilla infection model of OM, polymicrobial infection promoted M. catarrhalis persistence beyond the levels seen in animals infected with M. catarrhalis alone. Notably, no such enhancement of M. catarrhalis persistence was observed in animals infected with M. catarrhalis and a quorum signaling-deficient H. influenzae luxS mutant strain. We thus conclude that H. influenzae promotes M. catarrhalis persistence within polymicrobial biofilms via interspecies quorum signaling. AI-2 may therefore represent an ideal target for disruption of chronic polymicrobial infections. Moreover, these results strongly imply that successful vaccination against the unencapsulated H. influenzae strains that cause airway infections may also significantly impact chronic M. catarrhalis disease by removing a reservoir of the AI-2 signal that promotes M. catarrhalis persistence within biofilm.

  7. [Study on the counting of Streptococcus mutans, Streptococcus sanguis, Haemophilus actinomycetemcomitans by methyl thiazolyl tetrazolium colorimetric method].

    Science.gov (United States)

    Wang, Zhong-Chao; Fan, Li-Yuan; Jiang, Jun-Qiang; Cai, Wei; Ding, Yi

    2010-06-01

    To explore the feasibility of methyl thiazolyl tetrazolium (MTT) colorimetric method and the applied condition for the normal bacteria in the mouth, as Streptococcus mutans (S. mutans), Streptococcus sanguis (S. sanguis), Haemophilus actinomycetemcomitans (H. actinomycetemcomitans). Colony forming units (CFU) which was the standard antitheses was used to count bacteria. This study would gain some parameters by changing wavelength, reactive time, dosage and so on. MTT colorimetric method was applied in the counting of S. mutans, S. sanguis and H. actinomycetemcomitans. When counting S. mutans, the best wavelength was 510 nm, the best range was 1.5 x 10(5) - 1.0 x 10(7) CFU x mL(-1). When counting S. sanguis, the best wavelength was 545 nm, the best range was 1.5 x 10(5) - 2.0 x 10(7) CFU x mL(-1). When counting H. actinomycetemcomitans, the best wavelength was 557 nm, the best range was 1.0 x 10(6) - 5.0 x 10(7) CFU x mL(-1). MTT colorimetric method can be used for different aged S. mutans, S. sanguis and H. actinomycetemcomitans. Oral bacteria could be counted by MTT colorimetric method, which is fast and convenient.

  8. Post-GAVI sustainability of the Haemophilus influenzae type b vaccine program: The potential role of economic evaluation.

    Science.gov (United States)

    Le, Phuc; Nghiem, Van T; Swint, J Michael

    2016-09-01

    Haemophilus influenzae type b (Hib) can cause severe invasive diseases which are, however, preventable by vaccination. To increase access to Hib vaccine, GAVI - the Vaccine Alliance - has provided financial support for 73 lower income countries worldwide. At the same time, GAVI has been implementing its co-financing policy, requiring recipient countries to pay a portion of vaccine costs and to increase this amount over time. Starting in 2016, 5 countries will stop receiving GAVI funding and procure the vaccine themselves. Although the graduating countries have access to the UNICEF/GAVI tendered vaccine price for 5 more years, the uncertainty in market vaccine price may hamper the post-GAVI program sustainability. A possible increase in vaccine price would cause a significant burden on governmental budgets, discouraging countries to continue the program. As a special tool, economic evaluation (EE) can assist decision makers by identifying the maximum affordable vaccine price for countries to pay. Given that only 6 GAVI-eligible countries have such analyses published, more EEs are necessary to strengthen countries' commitment during this transition period. The information will also be useful for manufacturers to determine their pricing policy.

  9. The Haemophilus ducreyi trimeric autotransporter adhesin DsrA protects against an experimental infection in the swine model of chancroid.

    Science.gov (United States)

    Fusco, William G; Choudhary, Neelima R; Routh, Patty A; Ventevogel, Melissa S; Smith, Valerie A; Koch, Gary G; Almond, Glen W; Orndorff, Paul E; Sempowski, Gregory D; Leduc, Isabelle

    2014-06-24

    Adherence of pathogens to cellular targets is required to initiate most infections. Defining strategies that interfere with adhesion is therefore important for the development of preventative measures against infectious diseases. As an adhesin to host extracellular matrix proteins and human keratinocytes, the trimeric autotransporter adhesin DsrA, a proven virulence factor of the Gram-negative bacterium Haemophilus ducreyi, is a potential target for vaccine development. A recombinant form of the N-terminal passenger domain of DsrA from H. ducreyi class I strain 35000HP, termed rNT-DsrAI, was tested as a vaccine immunogen in the experimental swine model of H. ducreyi infection. Viable homologous H. ducreyi was not recovered from any animal receiving four doses of rNT-DsrAI administered with Freund's adjuvant at two-week intervals. Control pigs receiving adjuvant only were all infected. All animals receiving the rNT-DsrAI vaccine developed antibody endpoint titers between 3.5 and 5 logs. All rNT-DsrAI antisera bound the surface of the two H. ducreyi strains used to challenge immunized pigs. Purified anti-rNT-DsrAI IgG partially blocked binding of fibrinogen at the surface of viable H. ducreyi. Overall, immunization with the passenger domain of the trimeric autotransporter adhesin DsrA accelerated clearance of H. ducreyi in experimental lesions, possibly by interfering with fibrinogen binding. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Impact of Haemophilus influenzae type b conjugate vaccine on bacterial meningitis in the Dominican Republic Impacto de la vacuna conjugada contra Haemophilus influenzae tipo b sobre la meningitis bacteriana en la República Dominicana

    Directory of Open Access Journals (Sweden)

    Ellen H. Lee

    2008-09-01

    Full Text Available OBJECTIVES: Widespread use of Haemophilus influenzae type b (Hib vaccines has dramatically reduced the burden of Hib disease throughout the Americas. Few studies have evaluated the impact of Hib vaccination on non-culture-confirmed disease. This study analyzed trends in probable bacterial meningitis before and after the introduction of Hib vaccine in the Dominican Republic and estimated vaccine effectiveness against Hib meningitis. METHODS: Meningitis cases among children OBJETIVOS: El uso generalizado de la vacuna contra Haemophilus influenzae tipo b (Hib ha permitido reducir radicalmente la carga de enfermedad por Hib en las Américas. Pocos estudios han evaluado el impacto de la vacunación contra Hib sobre los casos no confirmados mediante cultivo. En este estudio se analizaron las tendencias en el número de casos probables de meningitis bacteriana antes y después de la introducción de la vacuna contra Hib en la República Dominicana y se estimó la eficacia de la vacuna contra la meningitis. MÉTODOS: Se identificaron los casos de meningitis en niños menores de 5 años a partir de los registros de ingreso del principal hospital pediátrico de Santo Domingo entre 1998 y 2004. Los casos de meningitis con probable etiología bacteriana se clasificaron según criterios de laboratorio; los casos confirmados contaban con cultivo bacteriano positivo o detección de antígenos específicos en el líquido cefalorraquídeo. Se calcularon las tasas de incidencia acumulada de casos confirmados y probables de meningitis en los niños que vivían en el Distrito Nacional. Los casos confirmados de meningitis por Hib se incorporaron a un estudio de casos y controles -pareados según la edad y el barrio de residencia- para calcular la eficacia de la vacuna. RESULTADOS: Antes de la introducción de la vacuna, la tasa anual de meningitis de posible etiología bacteriana era de 49 casos por 100 000 niños menores de 5 años; de los casos confirmados de

  11. Reclassification of Pasteurella gallinarum, [Haemophilus] paragallinarum, Pasteurella avium and Pasteurella volantium as Avibacterium gallinarum gen. nov., comb. nov., Avibacterium paragallinarum comb. nov., Avibacterium avium comb. nov. and Avibacterium volantium comb. nov.

    Science.gov (United States)

    Blackall, Patrick J; Christensen, Henrik; Beckenham, Tim; Blackall, Linda L; Bisgaard, Magne

    2005-01-01

    This paper describes a phenotypic and genotypic investigation of the taxonomy of [Haemophilus] paragallinarum, Pasteurella gallinarum, Pasteurella avium and Pasteurella volantium, a major subcluster within the avian 16S rRNA cluster 18 of the family Pasteurellaceae. An extended phenotypic characterization was performed of the type strain of [Haemophilus] paragallinarum, which is NAD-dependent, and eight NAD-independent strains of [Haemophilus] paragallinarum. Complete 16S rRNA gene sequences were obtained for one NAD-independent and four NAD-dependent [Haemophilus] paragallinarum strains. These five sequences along with existing 16S rRNA gene sequences for 11 other taxa within avian 16S rRNA cluster 18 as well as seven other taxa from the Pasteurellaceae were subjected to phylogenetic analysis. The analysis demonstrated that [Haemophilus] paragallinarum, Pasteurella gallinarum, Pasteurella avium and Pasteurella volantium formed a monophyletic group with a minimum of 96.8 % sequence similarity. This group can also be separated by phenotypic testing from all other recognized and named taxa within the Pasteurellaceae. As both genotypic and phenotypic testing support the separate and distinct nature of this subcluster, the transfer is proposed of Pasteurella gallinarum, [Haemophilus] paragallinarum, Pasteurella avium and Pasteurella volantium to a new genus Avibacterium as Avibacterium gallinarum gen. nov., comb. nov., Avibacterium paragallinarum comb. nov., Avibacterium avium comb. nov. and Avibacterium volantium comb. nov. The type strains are NCTC 1118T (Avibacterium gallinarum), NCTC 11296T (Avibacterium paragallinarum), NCTC 11297T (Avibacterium avium) and NCTC 3438T (Avibacterium volantium). Key characteristics that separate these four species are catalase activity (absent only in Avibacterium paragallinarum) and production of acid from galactose (negative only in Avibacterium paragallinarum), maltose (negative only in Avibacterium avium) and mannitol (negative

  12. Comprehensive Proteomic and Metabolomic Signatures of Nontypeable Haemophilus influenzae-Induced Acute Otitis Media Reveal Bacterial Aerobic Respiration in an Immunosuppressed Environment.

    Science.gov (United States)

    Harrison, Alistair; Dubois, Laura G; St John-Williams, Lisa; Moseley, M Arthur; Hardison, Rachael L; Heimlich, Derek R; Stoddard, Alexander; Kerschner, Joseph E; Justice, Sheryl S; Thompson, J Will; Mason, Kevin M

    2016-03-01

    A thorough understanding of the molecular details of the interactions between bacteria and host are critical to ultimately prevent disease. Recent technological advances allow simultaneous analysis of host and bacterial protein and metabolic profiles from a single small tissue sample to provide insight into pathogenesis. We used the chinchilla model of human otitis media to determine, for the first time, the most expansive delineation of global changes in protein and metabolite profiles during an experimentally induced disease. After 48 h of infection with nontypeable Haemophilus influenzae, middle ear tissue lysates were analyzed by high-resolution quantitative two-dimensional liquid chromatography-tandem mass spectrometry. Dynamic changes in 105 chinchilla proteins and 66 metabolites define the early proteomic and metabolomic signature of otitis media. Our studies indicate that establishment of disease coincides with actin morphogenesis, suppression of inflammatory mediators, and bacterial aerobic respiration. We validated the observed increase in the actin-remodeling complex, Arp2/3, and experimentally showed a role for Arp2/3 in nontypeable Haemophilus influenzae invasion. Direct inhibition of actin branch morphology altered bacterial invasion into host epithelial cells, and is supportive of our efforts to use the information gathered to modify outcomes of disease. The twenty-eight nontypeable Haemophilus influenzae proteins identified participate in carbohydrate and amino acid metabolism, redox homeostasis, and include cell wall-associated metabolic proteins. Quantitative characterization of the molecular signatures of infection will redefine our understanding of host response driven developmental changes during pathogenesis. These data represent the first comprehensive study of host protein and metabolite profiles in vivo in response to infection and show the feasibility of extensive characterization of host protein profiles during disease. Identification of

  13. CARACTERIZAÇÃO BIOQUÍMICA DE AMOSTRAS DE Haemophilus parasuis ISOLADAS DE SUÍNOS NA REGIÃO SUL DO BRASIL

    Directory of Open Access Journals (Sweden)

    Maria Aparecida Vasconcelos Paiva Brito

    1994-12-01

    Full Text Available O objetivo deste trabalho foi caracterizar amostras não hemolíticas de bactérias do gênero Haemophilus isoladas de suínos. As bactérias foram isoladas de material clínico de animais com suspeita da doença de Glässer, de leitões aparentemente sadios provenientes de quatro rebanhos com suspeita clínica desta doença e de casos de poliartrites. Além das características culturais e morfotintoriais, foram utilizados os seguintes testes para a identificação: dependência de NAD(fator V, CAMP, produção de hemolisina, indol, urease e catalase, redução do nitrato e produção de ácido dos carboidratos: glicose, sacarose, arabinose e manose. Dezessete dentre 24 amostras foram classificadas como Haemophilus parasuis (dez isoladas de animais clinicamente doentes e sete de leitões normais. Cinco destas amostras foram classificadas nos sorogrupos 2, 4, 7, ND4 e uma foi não tipável. Quatro das 24 amostras apresentaram características do grupo taxonômico C (teste de arabinose positivo e três produziram urease. Os testes realizados não permitiram distinguir as amostras urease positivas do gênero Haemophilus das amostras não hemolíticas de Actinobacilius pleuropneumoniae. Mais de 60% das amostras apresentaram sensibilidade in vitro a: ampicilina, cefalotina, cloranfenicol, danofioxacina, nitrofurantoína, penicilina G, polimixina B e tetraciclina.

  14. Effect of Multiple Mutations in the Hemoglobin- and Hemoglobin-Haptoglobin-Binding Proteins, HgpA, HgpB, and HgpC, of Haemophilus influenzae Type b

    OpenAIRE

    Morton, Daniel J.; Whitby, Paul W.; Jin, Hongfan; Ren, Zhen; Stull, Terrence L.

    1999-01-01

    Haemophilus influenzae requires heme for growth and can utilize hemoglobin and hemoglobin-haptoglobin as heme sources. We previously identified two hemoglobin- and hemoglobin-haptoglobin-binding proteins, HgpA and HgpB, in H. influenzae HI689. Insertional mutation of hgpA and hgpB, either singly or together, did not abrogate the ability to utilize or bind either hemoglobin or the hemoglobin-haptoglobin complex. A hemoglobin affinity purification method was used to isolate a protein of approxi...

  15. Mal de las vacas locas: su influencia en la obtención del antígeno principal de Haemophilus influenzae tipo b

    OpenAIRE

    Jonatan Hernández-Roche; Osmir Cabrera Blanco; Maribel Cuello-Pérez; Luis Riverón Martínez; Arturo Talavera Coronel; Ana H. Callís-Díaz; Gustavo Sierra-González

    2007-01-01

    Se evaluaron los parámetros fundamentales del proceso de obtención del polisacárido capsular de Haemophilus influenzae tipo b tales como: medio de cultivo, tipo de hemina empleada como factor de crecimiento y la expresión de cápsula polisacarídica por diferentes cepas. Los medios de cultivo evaluados fueron: infusión cerebro corazón, Mueller Hinton y una variante de Frantz modificado. Las heminas que fueron evaluadas procedieron de las casas comerciales siguientes: Fluka (origen bovino), Sigm...

  16. Haemophilus parainfluenzae causing sexually transmitted urethritis. Report of a case and evidence for a beta-lactamase plasmid mobilizable to Escherichia coli by an Inc-W plasmid.

    Science.gov (United States)

    Facinelli, B; Montanari, M P; Varaldo, P E

    1991-01-01

    A multiple antibiotic resistance, beta-lactamase-producing strain of Haemophilus parainfluenzae was isolated from a patient with sexually transmitted urethritis that was contracted in Northwest Africa. The strain was found to harbor a small (3.2 megadaltons) plasmid encoding for beta-lactamase production, which was successfully mobilized to Escherichia coli in triparental mating experiments by means of a broad host-range Inc-W conjugative plasmid. Since H. parainfluenzae is believed to be a source and reservoir for the spread of beta-lactamase plasmids to other bacterial species, such a plasmid mobilization may suggest a new possible means for resistance plasmid dissemination.

  17. Immunogenicity of a 2-dose priming and booster vaccination with the 10-valent pneumococcal nontypeable Haemophilus influenzae protein D conjugate vaccine

    DEFF Research Database (Denmark)

    Silfverdal, Sven Arne; Høgh, Birthe; Bergsaker, Marianne Riise

    2009-01-01

    BACKGROUND: The immunogenicity of the 10-valent pneumococcal nontypeable Haemophilus influenzae protein D-conjugate vaccine (PHiD-CV) was determined following a simplified 2-dose priming and the more commonly employed 3-dose priming both followed by a booster dose. METHODS: A total of 351 healthy...... subjects were primed with PHiD-CV at either 3 and 5 or 3, 4 and 5 months of age followed in all subjects by a booster dose at 11 to 12 months of age. Serotype-specific pneumococcal responses were measured by 22F-inhibition ELISA and opsonophagocytic assays 1 month following primary and booster vaccinations...

  18. A functional tonB gene is required for both virulence and competitive fitness in a chinchilla model of Haemophilus influenzae otitis media

    Directory of Open Access Journals (Sweden)

    Morton Daniel J

    2012-06-01

    Full Text Available Abstract Background Haemophilus influenzae requires heme for aerobic growth and possesses multiple mechanisms to obtain this essential nutrient. Methods An insertional mutation in tonB was constructed and the impact of the mutation on virulence and fitness in a chinchilla model of otitis media was determined. The tonB insertion mutant strain was significantly impacted in both virulence and fitness as compared to the wildtype strain in this model. Conclusions The tonB gene of H. influenzae is required for the establishment and maintenance of middle ear infection in this chinchilla model of bacterial disease.

  19. Antimicrobial resistance in Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis and group A beta-haemolytic streptococci in 2002-2003. Results of the multinational GRASP Surveillance Program

    DEFF Research Database (Denmark)

    Beekmann, Susan E; Heilmann, Kris P; Richter, Sandra S

    2005-01-01

    A multinational surveillance study, GRASP, was conducted between November 2002 and April 2003 with the aim of assessing rates of antimicrobial resistance among 2656 isolates of Streptococcus pneumoniae, 2486 isolates of group A beta-haemolytic streptococci, 1358 isolates of Haemophilus influenzae...... of MDR strains was above 25% in 8 of the 20 countries studied. Group A streptococcal macrolide resistance rates ranged from 0% to 35% by country, while rates of beta-lactamase production ranged from 0% to 39% for H. influenzae and 80-100% for M. catarrhalis. Antibiotic resistance in S. pneumoniae remains...

  20. The progeny of a single virgin B cell predominates the human recall B cell response to the capsular polysaccharide of Haemophilus influenzae type b

    DEFF Research Database (Denmark)

    Barington, T; Hougs, L; Juul, L

    1996-01-01

    of Haemophilus influenzae type b coupled to tetanus toxoid. We combined affinity purification of circulating vaccine-induced Ab-secreting cells with PCR amplification of cDNA followed by cloning and sequencing. Forty-eight and 42 kappa VJ gene transcripts were analyzed from two adults, respectively. Both...... of the cells originated from a common virgin B cell. Kinetic considerations implied that an extremely selected population of hypermutated memory B cells must have existed in these individuals before the first systemic immunization with the Ag. A possible role for the mucosal immune system in the priming...

  1. Fastidious Gram-Negatives: Identification by the Vitek 2 Neisseria-Haemophilus Card and by Partial 16S rRNA Gene Sequencing Analysis

    DEFF Research Database (Denmark)

    Wolff Sönksen, Ute; Christensen, Jens Jørgen; Nielsen, Lisbeth

    2010-01-01

    characterization using 100 fastidious Gram negative bacteria. Seventy-five strains represented 21 of the 26 taxa included in the Vitek 2 NH database and 25 strains represented related species not included in the database. Of the 100 strains, 31 were the type strains of the species. Vitek 2 NH identification......Taxonomy and identification of fastidious Gram negatives are evolving and challenging. We compared identifications achieved with the Vitek 2 Neisseria-Haemophilus (NH) card and partial 16S rRNA gene sequence (526 bp stretch) analysis with identifications obtained with extensive phenotypic...

  2. Artritis séptica de cadera por Haemophilus influenzae tipo F en la infancia: a propósito de un caso

    OpenAIRE

    N. Ulibarrena; de Andrés, C.; E. Bernaola; Herranz, M.; Moreno, L.; GARCÍA, S.

    2013-01-01

    La artritis séptica de cadera es una infección aguda, predominantemente de etiología bacteriana. A pesar de que el patógeno principal en cualquier grupo de edad es Staphylococcus aureus, existen otros microorganismos potencialmente patógenos. Describimos el caso de una paciente de 18 meses con artritis séptica de cadera por un agente causal infrecuente (Haemophilus influenzae tipo f) de buena evolución. Este caso pone de manifiesto la importancia de considerar otros agentes etiológicos menos ...

  3. Fastidious Gram-Negatives: Identification by the Vitek 2 Neisseria-Haemophilus Card and by Partial 16S rRNA Gene Sequencing Analysis

    DEFF Research Database (Denmark)

    Wolff Sönksen, Ute; Christensen, Jens Jørgen; Nielsen, Lisbeth

    2010-01-01

    Taxonomy and identification of fastidious Gram negatives are evolving and challenging. We compared identifications achieved with the Vitek 2 Neisseria-Haemophilus (NH) card and partial 16S rRNA gene sequence (526 bp stretch) analysis with identifications obtained with extensive phenotypic...... characterization using 100 fastidious Gram negative bacteria. Seventy-five strains represented 21 of the 26 taxa included in the Vitek 2 NH database and 25 strains represented related species not included in the database. Of the 100 strains, 31 were the type strains of the species. Vitek 2 NH identification...

  4. Dps promotes survival of nontypeable Haemophilus influenzae in biofilm communities in vitro and resistance to clearance in vivo

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    Bing ePang

    2012-05-01

    Full Text Available Nontypeable Haemophilus influenzae (NTHi is a common airway commensal and opportunistic pathogen that persists within surface-attached biofilm communities. In this study, we tested the hypothesis that bacterial stress-responses are activated within biofilms. Transcripts for several factors associated with bacterial resistance to environmental stress were increased in biofilm cultures as compared to planktonic cultures. Among these, a homolog of the DNA-binding protein from starved cells (dps was chosen for further study. An isogenic NTHi 86-028NP dps mutant was generated and tested for resistance to environmental stress, revealing a significant survival defects in high-iron conditions, which was mediated by oxidative stress and was restored by genetic complementation. As expected, NTHi 86-028NP dps had a general stress-response defect, exhibiting decreased resistance to many types of environmental stress. While no differences were observed in density and structure of NTHi 86-028NP and NTHi 86-028NP dps biofilms, bacterial survival was decreased in NTHi 86-028NP dps biofilms as compared to the parental strain. The role of dps persistence in vivo was tested in animal infection studies. NTHi 86-028NP dps had decreased resistance to clearance after pulmonary infection of elastase-treated mice as compared to NTHi 86-028NP, whereas minimal differences were observed in clearance from mock-treated mice. Similarly, lower numbers of NTHi 86-028NP dps were recovered from middle-ear effusions and bullar homogenates in the chinchilla model for otitis media. Therefore, we conclude that Dps promotes bacterial survival within NTHi biofilm communities both in vitro and in chronic infections in vivo.

  5. Sialic acid transport and catabolism are cooperatively regulated by SiaR and CRP in nontypeable Haemophilus influenzae

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    Johnston Jason W

    2010-09-01

    Full Text Available Abstract Background The transport and catabolism of sialic acid, a critical virulence factor for nontypeable Haemophilus influenzae, is regulated by two transcription factors, SiaR and CRP. Results Using a mutagenesis approach, glucosamine-6-phosphate (GlcN-6P was identified as a co-activator for SiaR. Evidence for the cooperative regulation of both the sialic acid catabolic and transport operons suggested that cooperativity between SiaR and CRP is required for regulation. cAMP was unable to influence the expression of the catabolic operon in the absence of SiaR but was able to induce catabolic operon expression when both SiaR and GlcN-6P were present. Alteration of helical phasing supported this observation by uncoupling SiaR and CRP regulation. The insertion of one half-turn of DNA between the SiaR and CRP operators resulted in the loss of SiaR-mediated repression of the transport operon while eliminating cAMP-dependent induction of the catabolic operon when GlcN-6P was present. SiaR and CRP were found to bind to their respective operators simultaneously and GlcN-6P altered the interaction of SiaR with its operator. Conclusions These results suggest multiple novel features for the regulation of these two adjacent operons. SiaR functions as both a repressor and an activator and SiaR and CRP interact to regulate both operons from a single set of operators.

  6. Invasive Haemophilus influenzae infections in Germany: impact of non-type b serotypes in the post-vaccine era

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    Milde-Busch Astrid

    2009-04-01

    Full Text Available Abstract Background Haemophilus influenzae type b (Hib vaccination led to a significant decrease in invasive bacterial infections in children. The aim of this study was to assess a potential shift to more non-type b invasive infections in a population with high Hib vaccination coverage and to compare the burden of suffering between children with Hib, capsulated non-b and non-capsulated Hi infections. Methods Cases with confirmed invasive Hi infections were ascertained through two independent nationwide active surveillance systems in 1998–2005. Information on possible predisposing conditions and clinical information was available from 2001 onwards. Results The total number of reported non-type b Hi cases varied between 10 cases in 1998, 27 in 2000 and 14 in 2005. In each year, non-capsulated serotypes outnumbered capsulated non-type b ones. 192 cases were detected in 2001–2005, more than one half was non-type b and 88% of the non-type b cases were non-capsulated. For cases with Hib/capsulated non-type b infections the most common clinical presentation was meningitis (67% each; 89%/78% had no potential predisposing condition, 75%/72% completely recovered from disease and 6% (each died. In contrast, meningitis was diagnosed in 34% of the non-capsulated Hi infections, septicaemia in 28% and pneumonia 21%; 62% had no potential predisposing condition, 83% completely recovered and 3% died. Conclusion There was no increase in non-type b Hi invasive infections during 8 years of active surveillance in Germany. Invasive disease due to non-type b Hi is not confined to children with risk factors. In patients with capsulated non-type b Hi infections the proportion of meningitis cases is similar to Hib, but double as high as in non-capsulated Hi.

  7. OxyR of Haemophilus parasuis is a global transcriptional regulator important in oxidative stress resistance and growth.

    Science.gov (United States)

    Wen, Yongping; Wen, Yiping; Wen, Xintian; Cao, Sanjie; Huang, Xiaobo; Wu, Rui; Zhao, Qin; Liu, Mafeng; Huang, Yong; Yan, Qigui; Han, Xinfeng; Ma, Xiaoping; Dai, Ke; Ding, Lingqiang; Liu, Sitong; Yang, Jian

    2018-02-15

    Haemophilus parasuis is an opportunistic pathogen and the causative agent of Glässer's disease in swine. This disease has high morbidity and mortality rates in swine populations, and is responsible for major economic losses worldwide. Survival of H. parasuis within the host requires mechanisms for coping with oxidative stress conditions. In many bacteria, OxyR is known to mediate protection against oxidative stress; however, little is known about the role of OxyR in H. parasuis. In the current study, an oxyR mutant strain was constructed in H. parasuis strain SC1401 and designated H. parasuis SC1401∆oxyR. The oxyR mutant strain had a slower growth rate and impaired biofilm formation compared to the wild type strain. Complementation restored the growth-associated phenotypes to wild type levels. Oxidative stress susceptibility testing, using a range of concentrations of H 2 O 2 , indicated that H. parasuis SC1401∆oxyR was more sensitive to oxidative stress than the wild type strain. RNA sequencing transcriptome analysis comparing H. parasuis SC1401 with H. parasuis SC1401∆oxyR identified 466 differentially expressed genes. These genes were involved in a wide range of biological processes, including: oxidative stress, transcriptional regulation, and DNA replication, recombination, and repair. These findings provide a foundation for future research to examine the role of OxyR as a global transcriptional regulator and to better define its role in oxidative stress resistance in H. parasuis. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Construction and immune effect of Haemophilus parasuis DNA vaccine encoding glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in mice.

    Science.gov (United States)

    Fu, Shulin; Zhang, Minmin; Ou, Jiwen; Liu, Huazhen; Tan, Chen; Liu, Jinlin; Chen, Huanchun; Bei, Weicheng

    2012-11-06

    Haemophilus parasuis, the causative agent of swine polyserositis, polyarthritis, and meningitis, is one of the most important bacterial diseases of pigs worldwide. The development of a vaccine against H. parasuis has been impeded due to the lack of induction of reliable cross-serotype protection. In this study the gapA gene that encodes glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was shown to be present and highly conserved in various serotypes of H. parasuis and we constructed a novel DNA vaccine encoding GAPDH (pCgap) to evaluate the immune response and protective efficacy against infection with H. parasuis MD0322 serovar 4 or SH0165 serovar 5 in mice. A significant antibody response against GAPDH was generated following pCgap intramuscular immunization; moreover, antibodies to the pCgap DNA vaccine were bactericidal, suggesting that it was expressed in vivo. The gapA transcript was detected in muscle, liver, spleen, and kidney of the mice seven days post-vaccination. The IgG subclass (IgG1 and IgG2a) analysis indicated that the DNA vaccine induced both Th1 and Th2 immune responses, but the IgG1 response was greater than the IgG2a response. Moreover, the groups vaccinated with the pCgap vaccine exhibited 83.3% and 50% protective efficacy against the H. parasuis MD0322 serovar 4 or SH0165 serovar 5 challenges, respectively. The pCgap DNA vaccine provided significantly greater protective efficacy compared to the negative control groups or blank control groups (P<0.05 for both). Taken together, these findings indicate that the pCgap DNA vaccine provides a novel strategy against infection of H. parasuis and offer insight concerning the underlying immune mechanisms of a bacterial DNA vaccine. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Applying Central Composite Design and Response Surface Methodology to Optimize Growth and Biomass Production of Haemophilus influenzae Type b.

    Science.gov (United States)

    Momen, Seyed Bahman; Siadat, Seyed Davar; Akbari, Neda; Ranjbar, Bijan; Khajeh, Khosro

    2016-06-01

    Haemophilus influenzae type b (Hib) is the leading cause of bacterial meningitis, otitis media, pneumonia, cellulitis, bacteremia, and septic arthritis in infants and young children. The Hib capsule contains the major virulence factor, and is composed of polyribosyl ribitol phosphate (PRP) that can induce immune system response. Vaccines consisting of Hib capsular polysaccharide (PRP) conjugated to a carrier protein are effective in the prevention of the infections. However, due to costly processes in PRP production, these vaccines are too expensive. To enhance biomass, in this research we focused on optimizing Hib growth with respect to physical factors such as pH, temperature, and agitation by using a response surface methodology (RSM). We employed a central composite design (CCD) and a response surface methodology to determine the optimum cultivation conditions for growth and biomass production of H. influenzae type b. The treatment factors investigated were initial pH, agitation, and temperature, using shaking flasks. After Hib cultivation and determination of dry biomass, analysis of experimental data was performed by the RSM-CCD. The model showed that temperature and pH had an interactive effect on Hib biomass production. The dry biomass produced in shaking flasks was about 5470 mg/L, which was under an initial pH of 8.5, at 250 rpm and 35° C. We found CCD and RSM very effective in optimizing Hib culture conditions, and Hib biomass production was greatly influenced by pH and incubation temperature. Therefore, optimization of the growth factors to maximize Hib production can lead to 1) an increase in bacterial biomass and PRP productions, 2) lower vaccine prices, 3) vaccination of more susceptible populations, and 4) lower risk of Hib infections.

  10. In vitro Dynamic Pharmacokinetic/Pharmacodynamic (PK/PD) study and COPD of Marbofloxacin against Haemophilus parasuis.

    Science.gov (United States)

    Sun, Jian; Xiao, Xia; Huang, Rui-Juan; Yang, Tao; Chen, Yi; Fang, Xi; Huang, Ting; Zhou, Yu-Feng; Liu, Ya-Hong

    2015-12-01

    Haemophilus parasuis (H. parasuis) can invade the body and cause systemic infection under stress conditions. Marbofloxacin has been recommended for the treatment of swine infections. However, few studies have investigated the PK/PD characteristics and PK/PD cutoff (COPD) of this drug against H. parasuis. MICs of marbofloxacin against 198 H. parasuis isolates were determined. The MIC50 and MIC90 were 2 and 8 mg/L, respectively. An in vitro dynamic PK/PD model was established to study the PK/PD relationship of marbofloxacin against H. parasuis. The PK/PD surrogate markers Cmax/MIC, Cmax/MPC (the maximum concentration divided by MIC or mutant prevention concentration (MPC)) and AUC 24h/MIC, AUC 24h/MPC (the area under the curve during the first 24 h divided by MIC or MPC) simulated the antimicrobial effect of marbofloxacin successfully with the R(2) of 0.9928 and 0.9911, respectively. The target values of 3-log10-unit and 4-log10-unit reduction for AUC 24h/MPC were 33 and 42, while the same efficacy for AUC 24h/MIC were 88 and 110. The COPD deduced from Monte Carlo simulation (MCS) for marbofloxacin against H. parasuis was 0.5 mg/L. The recommended dose of marbofloxacin against H. parasuis with MIC ≤ 2 mg/L was 16 mg/kg body weight (BW). The PK/PD surrogate markers AUC 24h/MIC, Cmax/MIC and AUC 24h/MPC, Cmax/MPC properly described the effects of marbofloxacin. Marbofloxacin can achieve the best efficacy at dosage of 16 mg/kg BW for strains with MIC values ≤ 2 mg/L, therefore, it is obligatory to know the sensitivity of the pathogen and to treat animals as early as possible. The very first COPD provide fundamental data for marbofloxacin breakpoint determination.

  11. A curated public database for multilocus sequence typing (MLST) and analysis of Haemophilus parasuis based on an optimized typing scheme.

    Science.gov (United States)

    Mullins, Michael A; Register, Karen B; Brunelle, Brian W; Aragon, Virginia; Galofré-Mila, Nuria; Bayles, Darrell O; Jolley, Keith A

    2013-03-23

    Haemophilus parasuis causes Glässer's disease and pneumonia in swine. Serotyping is often used to classify isolates but requires reagents that are costly to produce and not standardized or widely available. Sequence-based methods, such as multilocus sequence typing (MLST), offer many advantages over serotyping. An MLST scheme was previously proposed for H. parasuis but genome sequence data only recently available reveals the primers recommended, based on sequences of related bacteria, are not optimal. Here we report modifications to enhance the original method, including primer redesign to eliminate mismatches with H. parasuis sequences and to avoid regions of high sequence heterogeneity, standardization of primer T(m)s and identification of universal PCR conditions that result in robust and reproducible amplification of all targets. The modified typing method was applied to a collection of 127 isolates from North and South America, Europe and Asia. An alignment of the concatenated sequences obtained from seven target housekeeping genes identified 278 variable nucleotide sites that define 116 unique sequence types. A comparison of the original and modified methods using a subset of 86 isolates indicates little difference in overall locus diversity, discriminatory power or in the clustering of strains within Neighbor-Joining trees. Data from the optimized MLST were used to populate a newly created and publicly available H. parasuis database. An accompanying database designed to capture provenance and epidemiological information for each isolate was also created. The modified MLST scheme is highly discriminatory but more robust, reproducible and user-friendly than the original. The MLST database provides a novel resource for investigation of H. parasuis outbreaks and for tracking strain evolution. Published by Elsevier B.V.

  12. Cephalosporin-3'-Diazeniumdiolate NO Donor Prodrug PYRRO-C3D Enhances Azithromycin Susceptibility of Nontypeable Haemophilus influenzae Biofilms.

    Science.gov (United States)

    Collins, Samuel A; Kelso, Michael J; Rineh, Ardeshir; Yepuri, Nageshwar R; Coles, Janice; Jackson, Claire L; Halladay, Georgia D; Walker, Woolf T; Webb, Jeremy S; Hall-Stoodley, Luanne; Connett, Gary J; Feelisch, Martin; Faust, Saul N; Lucas, Jane S A; Allan, Raymond N

    2017-02-01

    PYRRO-C3D is a cephalosporin-3-diazeniumdiolate nitric oxide (NO) donor prodrug designed to selectively deliver NO to bacterial infection sites. The objective of this study was to assess the activity of PYRRO-C3D against nontypeable Haemophilus influenzae (NTHi) biofilms and examine the role of NO in reducing biofilm-associated antibiotic tolerance. The activity of PYRRO-C3D on in vitro NTHi biofilms was assessed through CFU enumeration and confocal microscopy. NO release measurements were performed using an ISO-NO probe. NTHi biofilms grown on primary ciliated respiratory epithelia at an air-liquid interface were used to investigate the effects of PYRRO-C3D in the presence of host tissue. Label-free liquid chromatography-mass spectrometry (LC/MS) proteomic analyses were performed to identify differentially expressed proteins following NO treatment. PYRRO-C3D specifically released NO in the presence of NTHi, while no evidence of spontaneous NO release was observed when the compound was exposed to primary epithelial cells. NTHi lacking β-lactamase activity failed to trigger NO release. Treatment significantly increased the susceptibility of in vitro NTHi biofilms to azithromycin, causing a log fold reduction (10-fold reduction or 1-log-unit reduction) in viability (P biofilms grown on primary respiratory epithelia, where a 2-log-unit reduction was observed (P biofilms, putatively via modulation of NTHi metabolic activity. Adjunctive therapy with NO mediated through PYRRO-C3D represents a promising approach for reducing biofilm-associated antibiotic tolerance. Copyright © 2017 American Society for Microbiology.

  13. Immunogenicity, reactogenicity and consistency of production of a Brazilian combined vaccine against diphtheria, tetanus, pertussis and Haemophilus influenzae type b

    Directory of Open Access Journals (Sweden)

    Reinaldo de Menezes Martins

    2008-11-01

    Full Text Available A randomized, double-blinded study evaluating the immunogenicity, safety and consistency of production of a combined diphtheria-tetanus-pertussis-Haemophilus influenzae type b vaccine entirely produced in Brazil by Bio-Manguinhos and Instituto Butantan (DTP/Hib-BM was undertaken. The reference vaccine had the same DTP vaccine but the Hib component was produced using purified materials supplied by GlaxoSmithKline (DTP/Hib-GSK, which is registered and has supplied the Brazilian National Immunization Program for over more than five years. One thousand infants were recruited for the study and received vaccinations at two, four and six months of age. With respect to immunogenicity, the vaccination protocol was followed in 95.6% and 98.4% of infants in the DTP/Hib-BM and DTP/Hib-GSK groups, respectively. For the Hib component of the study, there was 100% seroprotection (>0.15 µg/mL with all three lots of DTP/Hib-BM and DTP/Hib-GSK. The geometric mean titer (GMT was 9.3 µg/mL, 10.3 µg/mL and 10.3 µg/mL for lots 1, 2 and 3 of DTP/Hib-BM, respectively, and the GMT was 11.3 g/mL for DTP/Hib-GSK. For diphtheria, tetanus and pertussis, seroprotection was 99.7%, 100% and 99.9%, respectively, for DTP/Hib-BM, three lots altogether and 99.2%, 100% and 100% for DTP/Hib-GSK. GMTs were similar across all lots and vaccines. Adverse events rates were comparable among the vaccine groups. The Brazilian DTP/Hib vaccine demonstrated an immunogenicity and reactogenicity profile similar to that of the reference vaccine.

  14. Case of invasive nontypable Haemophilus influenzae respiratory tract infection with a large quantity of neutrophil extracellular traps in sputum.

    Science.gov (United States)

    Hamaguchi, Shigeto; Seki, Masafumi; Yamamoto, Norihisa; Hirose, Tomoya; Matsumoto, Naoya; Irisawa, Taro; Takegawa, Ryosuke; Shimazu, Takeshi; Tomono, Kazunori

    2012-01-01

    Haemophilus influenzae type b was once the most common cause of invasive H. influenzae infection, but the incidence of this disease has decreased markedly with introduction of conjugate vaccines to prevent the disease. In contrast, the incidence of invasive infection caused by nontypable H. influenzae has increased in the US and in European countries. Neutrophil extracellular traps (NETs) are fibrous structures released extracellularly from activated neutrophils during inflammation, including in pneumonia, and rapidly trap and kill pathogens as a first line of immunological defense. However, their function and pathological role have not been fully investigated. Here, we report a case of fatal nontypable H. influenzae infection with severe pneumonia and bacteremia in an adult found to have a vast amount of NETs in his sputum. The patient had a two-day history of common cold-like symptoms and was taken to the emergency room as a cardiopulmonary arrest. He recovered temporarily, but died soon afterwards, although appropriate antibiotic therapy and general management had been instituted. Massive lobular pneumonia and sepsis due to nontypable H. influenzae was found, in spite of H. influenzae type b vaccine being available. His sputum showed numerous bacteria phagocytosed by neutrophils, and immunohistological staining indicated a number of NETs containing DNA, histone H3, and neutrophil elastase. This case highlights an association between formation of NETs and severe respiratory and septic infection. An increase in severe nontypable H. influenzae disease can be expected as a result of "pathogen shift" due to increased use of the H. influenzae type b vaccine in Japan.

  15. Regulation of virulence gene expression resulting from Streptococcus pneumoniae and nontypeable Haemophilus influenzae interactions in chronic disease.

    Directory of Open Access Journals (Sweden)

    Emily K Cope

    Full Text Available Chronic rhinosinusitis (CRS is a common inflammatory disease of the sinonasal cavity mediated, in part, by polymicrobial communities of bacteria. Recent molecular studies have confirmed the importance of Streptococcus pneumoniae and nontypeable Haemophilus influenzae (NTHi in CRS. Here, we hypothesize that interaction between S. pneumoniae and NTHi mixed-species communities cause a change in bacterial virulence gene expression. We examined CRS as a model human disease to validate these polymicrobial interactions. Clinical strains of S. pneumoniae and NTHi were grown in mono- and co-culture in a standard biofilm assay. Reverse transcriptase real-time PCR (RTqPCR was used to measure gene expression of key virulence factors. To validate these results, we investigated the presence of the bacterial RNA transcripts in excised human tissue from patients with CRS. Consequences of physical or chemical interactions between microbes were also investigated. Transcription of NTHi type IV pili was only expressed in co-culture in vitro, and expression could be detected ex vivo in diseased tissue. S. pneumoniae pyruvate oxidase was up-regulated in co-culture, while pneumolysin and pneumococcal adherence factor A were down-regulated. These results were confirmed in excised human CRS tissue. Gene expression was differentially regulated by physical contact and secreted factors. Overall, these data suggest that interactions between H. influenzae and S. pneumoniae involve physical and chemical mechanisms that influence virulence gene expression of mixed-species biofilm communities present in chronically diseased human tissue. These results extend previous studies of population-level virulence and provide novel insight into the importance of S. pneumoniae and NTHi in CRS.

  16. Ampicillin-resistant Haemophilus influenzae isolates in Geneva: serotype, antimicrobial susceptibility, and β-lactam resistance mechanisms.

    Science.gov (United States)

    Cherkaoui, A; Diene, S M; Emonet, S; Renzi, G; Francois, P; Schrenzel, J

    2015-10-01

    The purpose of this study was to analyze the molecular mechanisms of ampicillin-resistant Haemophilus influenzae isolated in Geneva, Switzerland. We investigated the association between specific patterns of amino acid substitutions in penicillin-binding protein 3 (with or without β-lactamase production) and β-lactam susceptibility. Another main focus for this study was to compare the accuracy of disk diffusion and Etest methods to detect resistance to ampicillin and amoxicillin/clavulanic acid. The antibiotic susceptibility to β-lactam antibiotics of 124 H. influenzae isolates was determined by disk diffusion and Etest methods, and interpreted by European Committee on Antimicrobial Susceptibility Testing (EUCAST) and Clinical and Laboratory Standards Institute (CLSI) breakpoints. Alterations in PBP3 were investigated by sequencing the ftsI gene. Of the 124 clinical isolates analyzed, ampicillin resistance was found in 36% (45 out of 124). The rate of resistance to amoxicillin/clavulanic acid was 9% and 0.8%, using EUCAST and CLSI breakpoints respectively. For the 78 β-lactamase negative ampicillin-susceptible (BLNAS) isolates for which the Etest method indicated a high degree of susceptibility (MIC ≤ 1 mg/L), the disk diffusion method revealed resistance to ampicillin and amoxicillin/clavulanic acid in 33 cases (42%). Most common amino acid substitutions were Asn526Lys and Val547Ile, followed by Asp569Ser, Ala502Val, Asp350Asn, Met377Ile, Ile449Val, and Arg517His. The patterns observed were classified into six groups (IIa, IIb, IIc, IId, III-like, and miscellaneous). Continued characterization of both invasive and respiratory H. influenzae isolates is necessary in order to observe changes in the microbiology and epidemiology of this pathogen that could lead to clinical failure when treated by empirical antibiotic therapy.

  17. Immune responses to HBsAg conjugated to protein D of non-typeable Haemophilus influenzae in mice.

    Directory of Open Access Journals (Sweden)

    Qiudong Su

    Full Text Available Hepatitis B vaccine that contains an aluminum hydroxide adjuvant induces apoptotic death of Hepa 1-6 cells. Difficult-to-degrade chemical additives in vaccines effectively enhance vaccine immunogenicity, but also affect the host tissue. Identification of bio-molecules that are readily degraded and compatible in vivo as an adjuvant is important for vaccine research. The hapten-carrier effect suggests that stimulation of helper T (Th cells by carrier adjuvants is feasible. Protein D (PD of non-typeable Haemophilus influenzae covalently conjugated to some polysaccharide vaccines has been confirmed to convert T-cell independent (TI antigens into T-cell dependent (TD antigens, and elicit strong T-cell responses ultimately. Herein, we would substitube PD for aluminum hydroxide adjuvant in Hepatitis B vaccine.Truncated PD (amino acids 20-364 was expressed in Escherichia coli and purified by (NH42SO4 precipitation and DEAE chromatography. After evaluation of antigenicity by western blotting, PD was covalently conjugated to yeast-derived recombinant HBsAg by cross-linking with glutaraldehyde. Intramuscular immunization with the conjugate induced higher level of HBsAg-specific antibody than did HBsAg alone (p < 0.05, and was comparable to commercial Hepatitis B vaccine. During the surveillance period (days 35-105, anti-HBs titers were hold high. Moreover, the conjugated vaccine enhanced Th1 immune responses, while Th2 responses were also activated and induced an antibody response, as determined by IFN-γ ELISPOT and IgG1/IgG2a ratio assays.Recombinant truncated PD covalently conjugated to HBsAg antigen enhanced the immunogenicity of the antigen in mice simultaneously by humoral and cellular immune response, which would facilitate therapeutic hepatitis B vaccines.

  18. Enzyme-catalyzed acylation of homoserine: mechanistic characterization of the Haemophilus influenzae met2-encoded homoserine transacetylase.

    Science.gov (United States)

    Born, T L; Franklin, M; Blanchard, J S

    2000-07-25

    The first unique step in bacterial and plant methionine biosynthesis involves the acylation of the gamma-hydroxyl of homoserine. In Haemophilus influenzae, acylation is accomplished via an acetyl-CoA-dependent acetylation catalyzed by homoserine transacetylase. The activity of this enzyme regulates flux of homoserine into multiple biosynthetic pathways and, therefore, represents a critical control point for cell growth and viability. We have cloned homoserine transacetylase from H. influenzae and present the first detailed enzymatic study of this enzyme. Steady-state kinetic experiments demonstrate that the enzyme utilizes a ping-pong kinetic mechanism in which the acetyl group of acetyl-CoA is initially transferred to an enzyme nucleophile before subsequent transfer to homoserine to form the final product, O-acetylhomoserine. The maximal velocity and V/K(homoserine) were independent of pH over the range of values tested, while V/K(acetyl)(-)(CoA) was dependent upon the ionization state of a single group exhibiting a pK value of 8.6, which was required to be protonated. Solvent kinetic isotope effect studies yielded inverse effects of 0.75 on V and 0.74 on V/K(CoA) on the reverse reaction and effects of 1.2 on V and 1.7 on V/K(homoserine) on the forward reaction. Direct evidence for the formation of an acetyl-enzyme intermediate was obtained using rapid-quench labeling studies. On the basis of these observations, we propose a chemical mechanism for this important member of the acyltransferase family and contrast its mechanism with that of homoserine transsuccinylase.

  19. Genomic characterization of Haemophilus parasuis SH0165, a highly virulent strain of serovar 5 prevalent in China.

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    Zhuofei Xu

    Full Text Available Haemophilus parasuis can be either a commensal bacterium of the porcine respiratory tract or an opportunistic pathogen causing Glässer's disease, a severe systemic disease that has led to significant economical losses in the pig industry worldwide. We determined the complete genomic sequence of H. parasuis SH0165, a highly virulent strain of serovar 5, which was isolated from a hog pen in North China. The single circular chromosome was 2,269,156 base pairs in length and contained 2,031 protein-coding genes. Together with the full spectrum of genes detected by the analysis of metabolic pathways, we confirmed that H. parasuis generates ATP via both fermentation and respiration, and possesses an intact TCA cycle for anabolism. In addition to possessing the complete pathway essential for the biosynthesis of heme, this pathogen was also found to be well-equipped with different iron acquisition systems, such as the TonB system and ABC-type transport complexes, to overcome iron limitation during infection and persistence. We identified a number of genes encoding potential virulence factors, such as type IV fimbriae and surface polysaccharides. Analysis of the genome confirmed that H. parasuis is naturally competent, as genes related to DNA uptake are present. A nine-mer DNA uptake signal sequence (ACAAGCGGT, identical to that found in Actinobacillus pleuropneumoniae and Mannheimia haemolytica, followed by similar downstream motifs, was identified in the SH0165 genome. Genomic and phylogenetic comparisons with other Pasteurellaceae species further indicated that H. parasuis was closely related to another swine pathogenic bacteria A. pleuropneumoniae. The comprehensive genetic analysis presented here provides a foundation for future research on the metabolism, natural competence and virulence of H. parasuis.

  20. Genomic Characterization of Haemophilus parasuis SH0165, a Highly Virulent Strain of Serovar 5 Prevalent in China

    Science.gov (United States)

    Zhou, Rui; Jin, Qi; Fan, Yang; Bei, Weicheng; Chen, Huanchun

    2011-01-01

    Haemophilus parasuis can be either a commensal bacterium of the porcine respiratory tract or an opportunistic pathogen causing Glässer's disease, a severe systemic disease that has led to significant economical losses in the pig industry worldwide. We determined the complete genomic sequence of H. parasuis SH0165, a highly virulent strain of serovar 5, which was isolated from a hog pen in North China. The single circular chromosome was 2,269,156 base pairs in length and contained 2,031 protein-coding genes. Together with the full spectrum of genes detected by the analysis of metabolic pathways, we confirmed that H. parasuis generates ATP via both fermentation and respiration, and possesses an intact TCA cycle for anabolism. In addition to possessing the complete pathway essential for the biosynthesis of heme, this pathogen was also found to be well-equipped with different iron acquisition systems, such as the TonB system and ABC-type transport complexes, to overcome iron limitation during infection and persistence. We identified a number of genes encoding potential virulence factors, such as type IV fimbriae and surface polysaccharides. Analysis of the genome confirmed that H. parasuis is naturally competent, as genes related to DNA uptake are present. A nine-mer DNA uptake signal sequence (ACAAGCGGT), identical to that found in Actinobacillus pleuropneumoniae and Mannheimia haemolytica, followed by similar downstream motifs, was identified in the SH0165 genome. Genomic and phylogenetic comparisons with other Pasteurellaceae species further indicated that H. parasuis was closely related to another swine pathogenic bacteria A. pleuropneumoniae. The comprehensive genetic analysis presented here provides a foundation for future research on the metabolism, natural competence and virulence of H. parasuis. PMID:21611187

  1. Frequency of Spontaneous Resistance to Peptide Deformylase Inhibitor GSK1322322 in Haemophilus influenzae, Staphylococcus aureus, Streptococcus pyogenes, and Streptococcus pneumoniae.

    Science.gov (United States)

    Min, Sharon; Ingraham, Karen; Huang, Jianzhong; McCloskey, Lynn; Rilling, Sarah; Windau, Anne; Pizzollo, Jason; Butler, Deborah; Aubart, Kelly; Miller, Linda A; Zalacain, Magdalena; Holmes, David J; O'Dwyer, Karen

    2015-08-01

    The continuous emergence of multidrug-resistant pathogenic bacteria is compromising the successful treatment of serious microbial infections. GSK1322322, a novel peptide deformylase (PDF) inhibitor, shows good in vitro antibacterial activity and has demonstrated safety and efficacy in human proof-of-concept clinical studies. In vitro studies were performed to determine the frequency of resistance (FoR) to this antimicrobial agent in major pathogens that cause respiratory tract and skin infections. Resistance to GSK1322322 occurred at high frequency through loss-of-function mutations in the formyl-methionyl transferase (FMT) protein in Staphylococcus aureus (4/4 strains) and Streptococcus pyogenes (4/4 strains) and via missense mutations in Streptococcus pneumoniae (6/21 strains), but the mutations were associated with severe in vitro and/or in vivo fitness costs. The overall FoR to GSK1322322 was very low in Haemophilus influenzae, with only one PDF mutant being identified in one of four strains. No target-based mutants were identified from S. pyogenes, and only one or no PDF mutants were isolated in three of the four S. aureus strains studied. In S. pneumoniae, PDF mutants were isolated from only six of 21 strains tested; an additional 10 strains did not yield colonies on GSK1322322-containing plates. Most of the PDF mutants characterized from those three organisms (35/37 mutants) carried mutations in residues at or in close proximity to one of three highly conserved motifs that are part of the active site of the PDF protein, with 30 of the 35 mutations occurring at position V71 (using the S. pneumoniae numbering system). Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  2. Density Interactions between Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus in the Nasopharynx of Young Peruvian Children

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    Chien, Yu-Wen; Vidal, Jorge E.; Grijalva, Carlos G.; Bozio, Catherine; Edwards, Kathryn M.; Williams, John V.; Griffin, Marie R.; Verastegui, Hector; Hartinger, Stella M.; Gil, Ana I.; Lanata, Claudio F.; Klugman, Keith P.

    2012-01-01

    Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus are commonly carried in the nasopharynx (NP) of young children, and have been speculated to interact with each other. Although earlier studies used cultures alone to assess these interactions, the addition of real-time quantitative polymerase chain reaction (qPCR) provides further insight into these interactions. We compared results of culture and qPCR for the detection of these three bacteria in 446 NP samples collected from 360 healthy young children in a prospective cohort study in the Peruvian Andes. Patterns of concurrent bacterial colonization were studied using repeated measures logistic regression models with generalized estimating equations. Spearman correlation coefficients were employed to assess correlations among bacterial densities. At a bacterial density 105 CFU/ml. In addition, there was a positive association between S. pneumoniae and H. influenzae colonization measured by both culture (OR 3.11 – 3.17, p < 0.001) and qPCR (OR 1.95 – 1.97, p < 0.01). The densities of S. pneumoniae and H. influenzae, measured by qPCR, were positively correlated (correlation coefficient 0.32, p < 0.001). A negative association was found between the presence of S. pneumoniae and S. aureus in carriage with both culture (OR 0.45, p = 0.024) and qPCR (OR 0.61, p < 0.05). The impact of density on detection by culture and the observed density-related interactions support use of qPCR in additional studies to examine vaccine effects on diverse bacterial species. PMID:22935873

  3. Alloiococcus otitidis Forms Multispecies Biofilm with Haemophilus influenzae: Effects on Antibiotic Susceptibility and Growth in Adverse Conditions.

    Science.gov (United States)

    Chan, Chun L; Richter, Katharina; Wormald, Peter-John; Psaltis, Alkis J; Vreugde, Sarah

    2017-01-01

    Otitis media with effusion (OME) is a biofilm driven disease and commonly accepted otopathogens, such as Haemophilus influenzae, Streptococcus pneumonia, and Moraxella catarrhalis, have been demonstrated to form polymicrobial biofilms within the middle ear cleft. However, Alloiococcus otitidis (A. otitidis), which is one of the most commonly found bacteria within middle ear aspirates of children with OME, has not been described to form biofilms. The aim of this study was to investigate whether A. otitidis can form biofilms and investigate the impact on antibiotic susceptibility and survivability in polymicrobial biofilms with H. influenzae in vitro. The ability of A. otitidis to form single-species and polymicrobial biofilms with H. influenzae was explored. Clinical and commercial strains of A. otitidis and H. influenzae were incubated in brain heart infusion with and without supplementation. Biofilm was imaged using confocal laser scanning microscopy and scanning electron microscopy. Quantification of biofilm biomass and viable bacterial number was assessed using crystal violet assays and viable cell counting in both optimal growth conditions and in adverse growth conditions (depleted media and sub-optimal growth temperature). Antimicrobial susceptibility and changes in antibiotic resistance of single-species and multi-species co-culture were assessed using a microdilution method to assess minimal bactericidal concentration and E-test for amoxicillin and ciprofloxacin. A. otitidis formed single-species and polymicrobial biofilms with H. influenzae. Additionally, whilst strain dependent, combinations of polymicrobial biofilms decreased antimicrobial susceptibility, albeit a small magnitude, in both planktonic and polymicrobial biofilms. Moreover, A. otitidis promoted H. influenzae survival by increasing biofilm production in depleted media and at suboptimal growth temperature. Our findings suggest that A. otitidis may play an indirect pathogenic role in otitis

  4. A new model for non-typeable Haemophilus influenzae middle ear infection in the Junbo mutant mouse.

    Science.gov (United States)

    Hood, Derek; Moxon, Richard; Purnell, Tom; Richter, Caroline; Williams, Debbie; Azar, Ali; Crompton, Michael; Wells, Sara; Fray, Martin; Brown, Steve D M; Cheeseman, Michael T

    2016-01-01

    Acute otitis media, inflammation of the middle ear, is the most common bacterial infection in children and, as a consequence, is the most common reason for antimicrobial prescription to this age group. There is currently no effective vaccine for the principal pathogen involved, non-typeable Haemophilus influenzae (NTHi). The most frequently used and widely accepted experimental animal model of middle ear infection is in chinchillas, but mice and gerbils have also been used. We have established a robust model of middle ear infection by NTHi in the Junbo mouse, a mutant mouse line that spontaneously develops chronic middle ear inflammation in specific pathogen-free conditions. The heterozygote Junbo mouse (Jbo/+) bears a mutation in a gene (Evi1, also known as Mecom) that plays a role in host innate immune regulation; pre-existing middle ear inflammation promotes NTHi middle ear infection. A single intranasal inoculation with NTHi produces high rates (up to 90%) of middle ear infection and bacterial titres (10(4)-10(5) colony-forming units/µl) in bulla fluids. Bacteria are cleared from the majority of middle ears between day 21 and 35 post-inoculation but remain in approximately 20% of middle ears at least up to day 56 post-infection. The expression of Toll-like receptor-dependent response cytokine genes is elevated in the middle ear of the Jbo/+ mouse following NTHi infection. The translational potential of the Junbo model for studying antimicrobial intervention regimens was shown using a 3 day course of azithromycin to clear NTHi infection, and its potential use in vaccine development studies was shown by demonstrating protection in mice immunized with killed homologous, but not heterologous, NTHi bacteria. © 2016. Published by The Company of Biologists Ltd.

  5. A new model for non-typeable Haemophilus influenzae middle ear infection in the Junbo mutant mouse

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    Derek Hood

    2016-01-01

    Full Text Available Acute otitis media, inflammation of the middle ear, is the most common bacterial infection in children and, as a consequence, is the most common reason for antimicrobial prescription to this age group. There is currently no effective vaccine for the principal pathogen involved, non-typeable Haemophilus influenzae (NTHi. The most frequently used and widely accepted experimental animal model of middle ear infection is in chinchillas, but mice and gerbils have also been used. We have established a robust model of middle ear infection by NTHi in the Junbo mouse, a mutant mouse line that spontaneously develops chronic middle ear inflammation in specific pathogen-free conditions. The heterozygote Junbo mouse (Jbo/+ bears a mutation in a gene (Evi1, also known as Mecom that plays a role in host innate immune regulation; pre-existing middle ear inflammation promotes NTHi middle ear infection. A single intranasal inoculation with NTHi produces high rates (up to 90% of middle ear infection and bacterial titres (104-105 colony-forming units/µl in bulla fluids. Bacteria are cleared from the majority of middle ears between day 21 and 35 post-inoculation but remain in approximately 20% of middle ears at least up to day 56 post-infection. The expression of Toll-like receptor-dependent response cytokine genes is elevated in the middle ear of the Jbo/+ mouse following NTHi infection. The translational potential of the Junbo model for studying antimicrobial intervention regimens was shown using a 3 day course of azithromycin to clear NTHi infection, and its potential use in vaccine development studies was shown by demonstrating protection in mice immunized with killed homologous, but not heterologous, NTHi bacteria.

  6. [The cost-effectiveness of Haemophilus influenzae type b vaccine for children under 2 years of age in Colombia].

    Science.gov (United States)

    Alvis Guzmán, Nelson; De La Hoz Restrepo, Fernando; Vivas Consuelo, David

    2006-10-01

    Conjugate vaccines are the best public health tools available for preventing most invasive diseases caused by Haemophilus influenzae type b (Hib), but the high cost of the vaccines has so far kept them from being introduced worldwide. The objective of this study was to estimate the cost-effectiveness of introducing Hib conjugate vaccines for the prevention of meningitis and pneumonia among children under 2 years of age in Colombia. We estimated the direct and indirect costs of managing in-hospital pneumonia and meningitis cases. In addition, following the recommendations of the World Health Organization, we assessed the cost-effectiveness of Hib vaccination programs. We also estimated the costs for preventing Hib cases, and the cost per year of life saved in two hypothetical situations: (1) with vaccination against Hib (with 90% coverage) and (2) without vaccination. The average in-hospital treatment costs were 611.50 US$ (95% confidence interval (95% CI) = 532.2 to 690.8 US$) per case of pneumonia and 848.9 US$ (95% CI = 716.8 to 981.0 US$) per case of meningitis. The average cost per Hib case prevented was 316.7 US$ (95% CI = 294.2 to 339.2 US$). In terms of cost-effectiveness, the cost would be 2.38 US$ per year of life saved for vaccination, versus 3.81 US$ per year of life saved without vaccination. Having an adequate Hib vaccination program in Colombia could prevent around 25,000 cases of invasive disease per year, representing a cost savings of at least 15 million US$ annually. Furthermore, the program could prevent some 700 deaths per year and save 44,054 years of life per year.

  7. Polyarticular Septic Arthritis Caused by Haemophilus influenzae Serotype f in an 8-Month-Old Immunocompetent Infant: A Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Raheel Ahmed Ali

    2015-01-01

    Full Text Available Background. The standard use of vaccinations against pathogens has resulted in a decreased incidence of musculoskeletal infections caused by these previously common bacterial pathogens. Consequently, the incidence of infections caused by atypical bacteria is rising. This report presents a case of septic arthritis caused by non-type b H. influenzae in a pediatric patient. Methods. We report a case of an infant with polyarticular septic arthritis caused by H. influenzae serotype f. A literature review was conducted with the inclusion criteria of case reports and studies published between 2004 and 2013 addressing musculoskeletal H. influenzae infections. Results. An 8-month-old female presented with pain and swelling in her right ankle and left elbow. The patient was diagnosed with septic arthritis and underwent incision and drainage. Wound and blood cultures were positive for Haemophilus influenzae serotype f. In addition to treatment with IV antibiotics, the patient underwent immunocompetency studies, which were normal. Subsequent follow-up revealed eradication of the infection. Conclusions. Haemophilus influenzae non-type b may cause serious invasive infections such as sepsis or septic arthritis in children with or without predisposing factors such as immunodeficiency or asplenia. Optimal treatment includes surgical management, culture driven IV antibiotics, and an immunologic workup.

  8. Susceptibilities of beta-lactamase-producing and -nonproducing ampicillin-resistant strains of Haemophilus influenzae to ceftibuten, cefaclor, cefuroxime, cefixime, cefotaxime, and amoxicillin-clavulanic acid.

    Science.gov (United States)

    Barry, A L; Fuchs, P C; Pfaller, M A

    1993-01-01

    In in vitro studies we evaluated the susceptibilities of beta-lactamase-producing and -nonproducing, ampicillin-resistant strains of Haemophilus influenzae and compared them with those of ampicillin-susceptible strains. Ampicillin, amoxicillin-clavulanic acid, ceftibuten, cefaclor, cefuroxime, cefixime, and cefotaxime were evaluated by broth microdilution tests and disk diffusion tests. The disk diffusion tests accurately categorized beta-lactamase-producing strains and ampicillin-susceptible strains as being susceptible to the study drugs other than ampicillin. Ampicillin-resistant, beta-lactamase-nonproducing strains were relatively resistant to all seven study drugs, but the disk diffusion test did not always predict that resistance. The clinical relevance of the decreased susceptibility to various agents remains unclear, but to be conservative, all ampicillin-resistant, beta-lactamase-nonproducing strains might be assumed to be resistant to other beta-lactams. After excluding that small group of isolates, reliable susceptibility test results were obtained with lots of Haemophilus Test Medium that met quality assurance criteria. PMID:8431012

  9. Meningitis and pneumonia in Guatemalan children: the importance of Haemophilus influenzae type b and Streptococcus pneumoniae Meningitis y neumonía en niños guatemaltecos: importancia de Haemophilus influenzae tipo b y de Streptococcus pneumoniae

    Directory of Open Access Journals (Sweden)

    Edwin J. Asturias

    2003-12-01

    Full Text Available OBJECTIVE: To determine the epidemiology of Haemophilus influenzae type b (Hib and Streptococcus pneumoniae invasive infections in hospitalized Guatemalan children. This is an important issue since Hib vaccine has not been incorporated into the routine immunization program in Guatemala and information from hospital records in 1995 indicated a low incidence of Hib and S. pneumoniae as causes of meningitis and invasive infections. METHODS: Children who were hospitalized in Guatemala City with clinical signs compatible with bacterial infections were evaluated for evidence of Hib or S. pneumoniae infection. Normally sterile body fluids were cultured, and antigen detection was performed on cerebrospinal fluid (CSF and pleural fluid. RESULTS: Of 1 203 children 1-59 months of age hospitalized over a 28-month period, 725 of them (60.3% had a primary diagnosis of pneumonia, 357 (29.7% of meningitis, 60 (5.0% of cellulitis, and 61 (5.1% of sepsis and other conditions. Hib was identified in 20.0% of children with meningitis and S. pneumoniae in 12.9%. The average annual incidence of Hib meningitis was 13.8 cases per 100 000 children under 5 years of age, and 32.4% of meningitides caused by Hib and 58.7% of S. pneumoniae meningitides occurred prior to 6 months of age. Case fatality rates were 14.1%, 37.0%, and 18.0%, respectively, for children with Hib, S. pneumoniae, and culture-negative and antigen-negative meningitis. Prior antibiotic therapy was common and was associated with significant reductions in CSF-culture-positive results for children with other evidence of Hib or S. pneumoniae meningitis. CONCLUSIONS: Improvements in case detection, culture methods, and latex agglutination for antigen detection in CSF resulted in identification of Hib and S. pneumoniae as important causes of severe disease in Guatemalan children. Using a cutoff of > 10 white blood cells per cubic millimeter in CSF would improve the sensitivity for detection of bacterial

  10. Cross-protective efficacy of recombinant transferrin-binding protein A of Haemophilus parasuis in guinea pigs.

    Science.gov (United States)

    Huang, Xiaohui; Li, Yu; Fu, Yuguang; Ji, Yanhong; Lian, Kaiqi; Zheng, Haixue; Wei, Jianzhong; Cai, Xuepeng; Zhu, Qiyun

    2013-06-01

    The causative agent of Glasser's disease in swine is Haemophilus parasuis. Commercial bacterins are widely used for protection of the swine population. However, cross protection is limited because H. parasuis has more than 15 serovars. Transferrin-binding protein A has shown potential as a broad-spectrum vaccine candidate against homologous and heterologous strains. Here we amplified the full-length tbpA gene from an H. parasuis serovar 13 isolate and cloned it into a pET-SUMO expression vector. We then expressed and purified the TbpA protein by Ni affinity chromatography. First, the immunogenicity and protective efficacy of the protein were evaluated in guinea pigs by two subcutaneous immunizations with different doses of Montanide IMS 206 VG adjuvant. The immunized guinea pigs were, respectively, challenged on week 3 after a booster immunization with homologous strain LJ3 (serovar 13) and heterologous strain FX1 (serovar 4), and vaccine-inoculated groups were compared with nonvaccinated controls. All immunized groups showed serum antibody titers higher than those of negative-control groups. Furthermore, the cytokine and chemokine levels were evaluated at the transcriptional level by the real-time PCR analysis of six cytokines and chemokines. Gamma interferon and interleukin-5 in groups immunized with 100 μg were elevated more than 15-fold over those in negative-control groups. The protection rates were 80 and 60% after a challenge with strains LJ3 and FX1, respectively, in the groups vaccinated with 100 μg of recombinant TbpA protein. Subsequently, the data showed that guinea pigs immunized with a single dose (100 μg) were protected at levels of 80, 80, and 60% against LJ3, FX1, and another heterologous strain, SZ (serovar 14), respectively. The results indicate for the first time that TbpA protein cross protects guinea pigs against serovars 13, 4, and 14 of H. parasuis. Taken together, these results suggest that the recombinant TbpA protein is a promising

  11. Prospective multi-centre sentinel surveillance for Haemophilus influenzae type b & other bacterial meningitis in Indian children

    Science.gov (United States)

    Ramachandran, Padmanabhan; Fitzwater, Sean Patrick; Aneja, Satinder; Verghese, Valsan Philip; Kumar, Vishwajeet; Nedunchelian, Krishnamoorthy; Wadhwa, Nitya; Veeraraghavan, Balaji; Kumar, Rashmi; Meeran, Mohamed; Kapil, Arti; Jasmine, Sudha; Kumar, Aarti; Suresh, Saradha; Bhatnagar, Shinjini; Thomas, Kurien; Awasthi, Shally; Santosham, Mathuram; Chandran, Aruna

    2013-01-01

    Background & objectives: Haemophilus influenzae type b (Hib) is one of the leading bacterial causes of invasive disease in populations without access to Hib conjugate vaccines (Hib-CV). India has recently decided to introduce Hib-CV into the routine immunization programme in selected States. Longitudinal data quantifying the burden of bacterial meningitis and the proportion of disease caused by various bacteria are needed to track the impact of Hib-CV once introduced. A hospital-based sentinel surveillance network was established at four places in the country and this study reports the results of this ongoing surveillance. Methods: Children aged 1 to 23 months with suspected bacterial meningitis were enrolled in Chennai, Lucknow, New Delhi, and Vellore between July 2008 and June 2010. All cerebrospinal fluid (CSF) samples were tested using cytological, biochemical, and culture methods. Samples with abnormal CSF (≥10 WBC per μl) were tested by latex agglutination test for common paediatric bacterial meningitis pathogens. Results: A total of 708 patients with abnormal CSF were identified, 89 of whom had a bacterial pathogen confirmed. Hib accounted for the majority of bacteriologically confirmed cases, 62 (70%), while Streptococcus pneumoniae and group B Streptococcus were identified in 12 (13%) and seven (8%) cases, respectively. The other eight cases were a mix of other bacteria. The proportion of abnormal CSF and probable bacterial meningitis that was caused by Hib was 74 and 58 per cent lower at Christian Medical College (CMC), Vellore, which had a 41 per cent coverage of Hib-CV among all suspected meningitis cases, compared to the combined average proportion at the other three centres where a coverage between 1 and 8 per cent was seen (Pbacterial meningitis in young children in diverse geographic locations in India. Possible indications of herd immunity was seen at CMC compared to sites with low immunization coverage with Hib-CV. As Hib is the most common

  12. Type IV Pilus Expression Is Upregulated in Nontypeable Haemophilus influenzae Biofilms Formed at the Temperature of the Human Nasopharynx.

    Science.gov (United States)

    Mokrzan, Elaine M; Ward, Michael O; Bakaletz, Lauren O

    2016-10-01

    Nontypeable Haemophilus influenzae (NTHI), a commensal of the human nasopharynx (hNP), is a common cause of biofilm-associated diseases of the respiratory tract. However, NTHI biofilm biology at the average hNP temperature, i.e., 34°C, has not been well studied. Here we grew NTHI biofilms at 34°C and 37°C, to evaluate relative biofilm growth, expression, and function of the type IV pilus (Tfp), a critical adhesin important for NTHI biofilm formation. The kinetics and regulation of Tfp expression in NTHI biofilms are unclear, especially at 34°C. Tfp expression, as estimated by pilA promoter activity, was distributed throughout the biofilms, with a unique pattern that was dependent on temperature, time in culture, and position within the maturing biofilm. Tfp expression was required for the formation of the characteristic tower structures of NTHI biofilms and was significantly upregulated in NTHI biofilms formed at 34°C versus 37°C. This increase correlated with significantly greater twitching motility at 34°C than at 37°C. Treatment with antisera targeting the major subunit of Tfp (PilA) significantly inhibited NTHI biofilm formation at both temperatures, confirming the importance of this critical adhesin in biofilm formation. Additionally, treatment of preestablished biofilms with antisera against PilA significantly decreased biofilm biomass and mean thickness at both temperatures. These results demonstrated a pivotal role for Tfp in NTHI biofilm formation and stability at the temperature of the hNP, and they underscore the utility of PilA as a vaccine candidate for treatment and/or prevention of NTHI biofilm-associated diseases. NTHI is an important cause of chronic respiratory tract infections, including otitis media, chronic rhinosinusitis, and exacerbations of chronic obstructive pulmonary disease and cystic fibrosis. The chronic and recurrent nature of these diseases is attributed to the presence of bacterial biofilms, which are highly resistant to

  13. [In vitro resistance rates of Streptococcus pneumoniae and Haemophilus influenzae clinical isolates to the antibiotics used in therapy].

    Science.gov (United States)

    Uncu, Hikmet; Colakoğlu, Sule; Turunç, Tuba; Demiroğlu, Yusuf Ziya; Arslan, Hande

    2007-07-01

    Streptococcus pneumoniae and Haemophilus influenzae which cause infections with high morbidity and mortality all over the world, are also the most important bacterial pathogens of community-acquired pneumoniae. In recent years S. pneumoniae is becoming increasingly resistant to a variety of antibiotics. The aim of this study was to detect the in vitro resistance rates of S. pneumoniae and H. influenzae strains isolated from different clinical samples to the antibiotics which are used in the therapy of infections due to these pathogens. Between the period of January 2005 to May 2006, 77 S. pneumoniae (44 sputum, 20 blood, 8 bronchoalveolar lavage, 4 pleural fluids and 1 tracheal aspirate isolate) and 31 H. influenzae (30 sputum and 1 bronchoalveolar lavage isolate) strains isolated from patients who were admitted to Baskent University Hospital, Research and Practice Center of Adana (located in southern Turkey), were included to the study. The antibiotic susceptibility tests were performed by disc diffusion method according to CLSI (Clinical and Laboratory Standards Institute; M100-S13) guidelines. The MIC values of S. pneumoniae which gave an inhibition zone diameter of > or =19 mm in with disc diffusion test, were detected by E-test (AB Biodisk, Sweden). Intermediate and high resistance rates of pneumococci to penicilin were found as 38.9% (30/77) and 10.4% (8/77), respectively, with a total resistance rate of 49.4%. Trimethoprim-sulphamethoxazole (TMP/SMX), erithromycin, tetracyclin, clindamycin and chloramphenicol were the other antibiotics which followed penicillin with the resistance rates of 42.8%, 37.6%, 31.1%, 23.3% and 10.3%, respectively. Amongst H. influenzae strains, one (3.2%) was found to be a beta-lactamase producer and it was resistant to both ampicillin and azitromycin. Eight (25.8%) of H. influenzae isolates were resistant to TMP/SMX, and two (6.4%) were resistant to chloramphenicol. As a result, the high penicilin and erithromycin resistance rates

  14. TRIVAC decision-support model for evaluating the cost-effectiveness of Haemophilus influenzae type b, pneumococcal and rotavirus vaccination.

    Science.gov (United States)

    Clark, Andrew; Jauregui, Barbara; Griffiths, Ulla; Janusz, Cara B; Bolaños-Sierra, Brenda; Hajjeh, Rana; Andrus, Jon K; Sanderson, Colin

    2013-07-02

    The TRIVAC decision support model has been used widely in Latin America and other regions to help national teams evaluate the cost-effectiveness of Haemophilus influenzae type b (Hib) vaccine, pneumococcal conjugate vaccine (PCV) and rotavirus vaccine (RV). We describe the structure and functioning of this model, and identify the parameters with the greatest influence on the results. The TRIVAC model is a spreadsheet software program that calculates incremental cost-effectiveness ratios (ICERs) and other indicators for three childhood vaccines (Hib, PCV and RV) utilising parameters such as demography, disease burden, vaccine costs, vaccine coverage, vaccine efficacy, health service utilisation and costs. There is a good deal of uncertainty about the local values of many of the parameters that have most influence on the cost-effectiveness of these new vaccines. Cost-effectiveness models can be used to explore the implications of different values of these parameters. However, for such models to be seen as relevant and helpful by decision-makers, they need to be transparent, flexible, easy to use, and embedded in a process which is owned and led by national teams. In this paper the key drivers of cost-effectiveness in the model are identified by one-way sensitivity analyses, run for each vaccine in 147 countries. The data used are mainly from standard international sources and the published literature. The primary indicator was the discounted cost per Disability Adjusted Life-Year (DALY) averted, from a government perspective, over a 20-year period (2013-2032). For all three vaccines, the ICER was most sensitive to changes in relative coverage (the coverage of the children who would have become diseased or, more importantly, died if the population had not been vaccinated, as a % of overall national coverage) and the herd effect multiplier. Other influential parameters for all three vaccines were: the incidence and case fatality of disease, the baseline trend in

  15. [Antibacterial susceptibility surveillance of Haemophilus influenzae isolated from pediatric patients in Gifu and Aichi prefectures (2009-2010)].

    Science.gov (United States)

    Takakura, Mariko; Fukuda, Yoshiko; Nomura, Nobuhiko; Mitsuyama, Junichi; Yamaoka, Kazukiyo; Asano, Yuko; Sawamura, Haruki; Katsuragawa, Kouichi; Hashido, Hikonori; Matsukawa, Yoko; Matsubara, Shigenori; Oota, Hirotoshi; Watanabe, Kunitomo; Yamagishi, Yuka; Mikamo, Hiroshige

    2012-10-01

    We investigated the susceptibility to antibacterial agents of 197 strains of Haemophilus influenzae isolated from pediatric patients at medical facilities in Gifu and Aichi prefectures between 2009 and 2010. Those strains were also examined for the mutations of ftsI coding for penicillin-binding protein 3, presence of bla TEM-1, serotype and beta-lactamase producing ability. Among the 197 strains, the most prevalent serotype was non-typeable (89.8%), followed by serotype b (8.1%), e (1.5%) and f (0.5%). Based on the susceptibility among the 197 strains to antibacterial agents, beta-lactamase nonproducing ampicillin-susceptible H. influenzae (BLNAS) accounted for 27.4%, beta-lactamase nonproducing ampicillin-resistant H. influenzae (BLNAR) for 62.4%, beta-lactamase producing ampicillin-resistant H. influenzae (BLPAR) for 6.1% and beta-lactamase producing amoxicillin/ clavulanic acid-resistant H. influenzae (BLPACR) for 4.1%. According to PCR-based genotyping, the strains were classified into 6 categories: gBLNAS, gLow-BLNAR, gBLNAR, gBLPAR, gBLPACR-I and gBLPACR-II. The incidences of each resistant class were 17.3% for gBLNAS, 6.6% for gLow-BLNAR, 66.0% for gBLNAR, 5.6% for gBLPAR and 4.6% for gBLPACR-II. The combined incidence of gLow-BLNAR and gBLNAR was 72.6%, which was higher than that of BLNAR (62.4%). The MIC90s of antibacterial agents against the 197 strains were as follows; 0.0156 microg/mL for tosufloxacin and garenoxacin, 0.0313 microg/mL for levofloxacin and pazufloxacin, 0.0625 microg/mL for norfloxacin, 0.25 microg/mL for tazobactam/piperacillin (TAZ/PIPC) and ceftriaxone, 0.5 microg/mL for TAZ/PIPC (1:8) and cefditoren, 1 microg/mL for piperacillin, cefteram, cefotaxime, meropenem, tebipenem and minocycline, 2 microg/mL for doripenem, 4 microg/mL for cefcapene, imipenem and azithromycin, 8 microg/mL for sulbactam/ampicillin, clavulanic acid/amoxicillin (1:2, CVA/AMPC) and cefdinir, 16 microg/mL for CVA/AMPC (1:14), flomoxef and clarithromycin, 32

  16. Haemophilus influenzae LicB contributes to lung damage in an aged mice co-infection model.

    Science.gov (United States)

    Bondy, Jessica; Osharovich, Sofya; Storm, Julie; Durning, Graham; McAuliffe, Timothy; Fan, Xin

    2016-01-01

    Phosphorylcholine (ChoP) decoration of lipopolysaccharides is an important virulence strategy adopted by Haemophilus influenzae to establish a niche on the mucosal surface and to promote adherence to the host cells. The incorporation of ChoP on the LPS surface involves the lic1 operon, which consists of the licA, licB, licC, and licD genes. Among which, licB is a choline transporter gene required for acquisition of choline from environmental sources. In this study, we investigated the pathogenesis of the licB gene in an aged mice infection model. Due to immediate clearance of H. influenzae upon infection in mice, we employed influenza A virus and H. influenzae co-infection model. Our data showed that in the co-infection model, the secondary bacterial infection with a very low H. influenzae concentration of 100 colony forming unit is lethal to the aged mice. Although we did not observe any differences in weight loss between parent and licB mutant strains during the course of infection, a significant reduction of lung tissue damage was observed in the licB mutant infected aged mice. These results suggest that the licB gene is a virulence factor during H. influenzae infection in the lung in aged mice, possibly due to the increased binding to the host cell receptor via ChoP expression on the bacterial surface. In addition, when aged mice and mature mice were compared in the challenge experiments, we did not observe any protective immunity in the co-infection model suggesting the detrimental effects of the secondary bacterial infection on the aged mice in contrast to obvious immune-protections observed in the mature mice. The results of our experiments also implied that the co-infection model with influenza A virus and H. influenzae may be employed as a model system to study H. influenzae pathogenesis in vivo in aged mice. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Disinfection of rigid nasal endoscopes following in vitro contamination with Staphylococcus aureus, Streptococcus pneumoniae, Pseudomonas aeruginosa, and Haemophilus influenzae.

    Science.gov (United States)

    Bradford, Benjamin D; Seiberling, Kristin A; Park, Francine E; Hiebert, Jared C; Chang, Dennis F

    2013-06-01

    If not adequately cleaned, rigid nasal endoscopes (RNEs) have the potential to cause iatrogenic cross-contamination. To test the efficacy of various disinfection methods in reducing bacterial load on RNEs in vitro. In vitro model. Staphylococcus aureus, Streptococcus pneumoniae, Pseudomonas aeruginosa, and Haemophilus influenzae contamination was separately induced on RNEs in vitro. Two experimental sets were completed. The RNEs were disinfected using the following protocols: 30-second scrub with antimicrobial soap (ABS) and water, 30-second scrub with 70% isopropyl alcohol (IA), 30-second scrub with ABS followed by 30-second scrub with IA, 30-second scrub with germicidal cloth, isolated 5-minute soak in an enzymatic soap solution, 5- and 10-minute soaks in ortho-phthalaldehyde, 0.55%, solution (Cidex OPA), and isolated 30-second rinse with tap water, all with 30-second precleaning and postcleaning rinses with tap water. Two sets of experiments (experiment sets A and B) were carried out with a 30-second tap water rinse after inoculation of each RNE. This was followed by immediate cleaning in set A and a 1-hour air-dry delay in set B. Otherwise there were no differences in the disinfection protocols between sets for each method noted. Effectiveness of various disinfection protocols in cleaning rigid nasal endoscopes experimentally inoculated with bacteria commonly found in the upper aerodigestive tract. Positive cultures following disinfection indicated ineffective or incomplete disinfection. Most cleaning methods were effective in eliminating S aureus, S pneumoniae, and H influenzae from the scopes following experimental contamination. Continued growth of P aeruginosa was found after all of the disinfection trials in experiment set A with the exception of a 10-minute immersion in Cidex OPA, and in set B except for the 10-minute Cidex OPA immersion and ABS plus IA trials. Most cleaning methods used in our trials appear to properly disinfect RNEs after in vitro

  18. Mechanisms of skin adherence, penetration and tissue necrosis production by Haemophilus ducreyi, the causative agent of chancroid.

    Science.gov (United States)

    Abeck, D; Korting, H C

    1992-01-01

    Haemophilus ducreyi (H. ducreyi) strains, representing both reference strains and low-passage isolates, were investigated in terms of surface structures and enzymatic equipment. The interaction of these factors with host tissue was analysed using new in vitro- and in vivo-models. By electron microscopy studies there was no evidence of an extracellular capsule or surface appendages such as pili or flagella. Interaction of all isolates tested with the lectin Phaseolus vulgaris suggests N-acetyl-D-glucosamine units as common structural features of H. ducreyi cell envelope polysaccharide. In attachment to epithelial cells more than one hemagglutinin might be implicated as different haemagglutination patterns could be observed whereby the activity was not heat-labile, but was abolished by formaldehyde. Hydrophobic interactions might be of importance as well as strains showed a wide range of reactions from hydrophobic to hydrophilic, low hydrophobicity being more marked with the older strains. No elaboration of degradative enzymes based on the measurement of enzymatic activity using insoluble dye-protein complexes could be detected in case of H. ducreyi, using Azocoll and Remazol Brilliantblue hide powder for detection of proteolytic activity and elastinorcein for detection of elastase activity. In vitro studies using human keratinocytes and Vero cells did not show any morphological changes when incubated with H. ducreyi culture filtrates. In vivo studies with a new mouse model for H. ducreyi infection could confirm the results of the in vitro studies. Mere contact to undamaged skin both of whole cell organisms, live or heat-killed, and of culture filtrates did not lead to any reaction or even damage of mouse skin. However, when the outer epidermal layer was overcome by intradermal injection of shaved mice ulcers developed. Tissue necrosis production was not bound to live organisms as dead ones showed the same effect. There is great evidence that this tissue necrosis is

  19. Exposure Prophylaxis

    African Journals Online (AJOL)

    opsig

    have the potential for exposure to infectious material, for example blood ... body fluid; wound causing bleeding and produced by sharp instrument ... Full blood count. Liver function test. Renal function test. HIV screening. Pregnancy test if EFV is considered. Two weeks. Full blood count. Liver function test. Renal function test.

  20. Evaluación de reactivos cubanos elaborados para el diagnóstico rápido de Haemophilus influenzae tipo B

    Directory of Open Access Journals (Sweden)

    Gilda Toraño Peraza

    2001-08-01

    Full Text Available Se probaron en la detección del antígeno capsular específico de haemophilus influenzae tipo b (Hib, un reactivo de látex y un antisuero para contrainmunoelectroforesis (CIE e hinchazón capsular (HC, producidos en el Laboratorio de Infecciones Respiratorias Agudas Bacterianas del Instituto «Pedro Kourí». Se evaluaron los reactivos en el serotipaje de 786 cepas de Haemophilus influenzae aisladas de procesos invasivos y de portadores nasofaríngeos, y en el diagnóstico rápido a partir de muestras de líquido cefalorraquídeo, suero y orina de 258 pacientes con diagnóstico clínico de meningoencefalitis. Se obtuvieron satisfactorios índices de sensibilidad y especificidad, los que fueron determinados utilizando como referencia el antisuero para Hib comercializado por la DIFCO para la técnica de HC y CIE, y el reactivo de látex Wellcogen para el diagnóstico de Hib. Se propone la validación de ambos reactivos por parte de los organismos nacionales acreditados, para que estos puedan ser introducidos en la red cubana de salud pública.A latex reagent and an antiserum for counterimmunoelectrophoresis (CIEand capsular swelling (CS, both produced by the Acute Bacterial Respiratory Infections Lab of "Pedro Kourí" Institute were tested in the detection of a Haemophilus influenzae type B- specific capsular antigen. The reagents were evaluated in the serotyping of 786 Hib strains isolated from invasive diseases and nasopharyngeal carriers and in the rapid diagnosis of cerebrospinal fluid, serum and urine samples taken from 258 patients with clinical diagnosis of meningoencephalitis. Satisfactory sensitiviy and specificity indexes were obtained, which were determined by using Hib antiserum traded by DIFCO for CS technique and CIE and latex reagent Wellcogen for the Hib diagnosis as a reference. This paper proposes the validation of both reagents by authorized national bodies so that they can be introduced in the Cuban health care network.

  1. Exposures series

    OpenAIRE

    Stimson, Blake

    2011-01-01

    Reaktion Books’ Exposures series, edited by Peter Hamilton and Mark Haworth-Booth, is comprised of 13 volumes and counting, each less than 200 pages with 80 high-quality illustrations in color and black and white. Currently available titles include Photography and Australia, Photography and Spirit, Photography and Cinema, Photography and Literature, Photography and Flight, Photography and Egypt, Photography and Science, Photography and Africa, Photography and Italy, Photography and the USA, P...

  2. A clinical trial examining the effect of increased total CRM(197) carrier protein dose on the antibody response to Haemophilus influenzae type b CRM(197) conjugate vaccine.

    Science.gov (United States)

    Usonis, Vytautas; Bakasenas, Vytautas; Lockhart, Stephen; Baker, Sherryl; Gruber, William; Laudat, France

    2008-08-18

    CRM(197) is a carrier protein in certain conjugate vaccines. When multiple conjugate vaccines with the same carrier protein are administered simultaneously, reduced response to vaccines and/or antigens related to the carrier protein may occur. This study examined responses of infants who, in addition to diphtheria toxoid/tetanus toxoid/acellular pertussis vaccine (DTaP) received either diphtheria CRM(197)-based Haemophilus influenzae type b conjugate vaccine (HbOC) or HbOC and a diphtheria CRM(197)-based combination 9-valent pneumococcal conjugate vaccine/meningococcal group C conjugate vaccine. Administration of conjugate vaccines with CRM(197) carrier protein load >50 microg did not reduce response to CRM(197) conjugate vaccines or immunogenicity to immunologically cross-reactive diphtheria toxoid.

  3. Opposite effects of actively and passively acquired immunity to the carrier on responses of human infants to a Haemophilus influenzae type b conjugate vaccine

    DEFF Research Database (Denmark)

    Barington, T; Gyhrs, A; Kristensen, Kim

    1994-01-01

    Vaccination of infants with Haemophilus influenzae type b (Hib) capsular polysaccharide (HibCP) coupled to carrier proteins has proven protective against invasive Hib diseases in several trials. However, insufficient immunogenicity has been noted in certain populations. Therefore, studies analyzing...... factors influencing the antibody response to conjugate vaccines are needed. In this study, the response to HibCP coupled to tetanus toxoid (TT) was examined in relation to (i) priming with or coadministration of the carrier protein and (ii) the levels of passively acquired maternal TT antibodies. One...... hundred forty-four infants were vaccinated with HibCP-TT at 5 and 6 months. They were randomized into three groups that received TT as part of a diphtheria-tetanus-polio vaccine at either 6 and 7 months (group A), 5 and 6 months (group B), or 4 and 5 months (group C). Maternally acquired TT antibodies...

  4. Characterization of the antibody response to a Haemophilus influenzae type b conjugate vaccine in children with recurrent lower respiratory tract infection

    DEFF Research Database (Denmark)

    Kristensen, K; Barington, T; Pressler, T

    1995-01-01

    once with a Haemophilus influenzae type b (Hib) conjugate vaccine. Total IgG subclasses, total antipolysaccharide Hib antibodies, and antipolysaccharide Hib antibodies of IgM, IgG, IgA, and IgG1-4 specificity were determined by ELISA. There were no significant differences between the two groups in any...... single total IgG subclass, but total IgG measured as the sum of all four subclasses was significantly lower in the children with RLRI than in the controls (P = 0.036). Before vaccination, the children with RLRI had significantly less IgG antipolysaccharide Hib antibody than the controls (P = 0......M response to Hib conjugate vaccine in these children, since this isotype predominates in the primary immune response, i.e., in the absence of immunologic memory.(ABSTRACT TRUNCATED AT 250 WORDS)...

  5. Antagonism of miR-328 increases the antimicrobial function of macrophages and neutrophils and rapid clearance of non-typeable Haemophilus influenzae (NTHi from infected lung.

    Directory of Open Access Journals (Sweden)

    Hock L Tay

    2015-04-01

    Full Text Available Pathogenic bacterial infections of the lung are life threatening and underpin chronic lung diseases. Current treatments are often ineffective potentially due to increasing antibiotic resistance and impairment of innate immunity by disease processes and steroid therapy. Manipulation miRNA directly regulating anti-microbial machinery of the innate immune system may boost host defence responses. Here we demonstrate that miR-328 is a key element of the host response to pulmonary infection with non-typeable haemophilus influenzae and pharmacological inhibition in mouse and human macrophages augments phagocytosis, the production of reactive oxygen species, and microbicidal activity. Moreover, inhibition of miR-328 in respiratory models of infection, steroid-induced immunosuppression, and smoke-induced emphysema enhances bacterial clearance. Thus, miRNA pathways can be targeted in the lung to enhance host defence against a clinically relevant microbial infection and offer a potential new anti-microbial approach for the treatment of respiratory diseases.

  6. Antagonism of miR-328 increases the antimicrobial function of macrophages and neutrophils and rapid clearance of non-typeable Haemophilus influenzae (NTHi) from infected lung.

    Science.gov (United States)

    Tay, Hock L; Kaiko, Gerard E; Plank, Maximilian; Li, JingJing; Maltby, Steven; Essilfie, Ama-Tawiah; Jarnicki, Andrew; Yang, Ming; Mattes, Joerg; Hansbro, Philip M; Foster, Paul S

    2015-04-01

    Pathogenic bacterial infections of the lung are life threatening and underpin chronic lung diseases. Current treatments are often ineffective potentially due to increasing antibiotic resistance and impairment of innate immunity by disease processes and steroid therapy. Manipulation miRNA directly regulating anti-microbial machinery of the innate immune system may boost host defence responses. Here we demonstrate that miR-328 is a key element of the host response to pulmonary infection with non-typeable haemophilus influenzae and pharmacological inhibition in mouse and human macrophages augments phagocytosis, the production of reactive oxygen species, and microbicidal activity. Moreover, inhibition of miR-328 in respiratory models of infection, steroid-induced immunosuppression, and smoke-induced emphysema enhances bacterial clearance. Thus, miRNA pathways can be targeted in the lung to enhance host defence against a clinically relevant microbial infection and offer a potential new anti-microbial approach for the treatment of respiratory diseases.

  7. Non-epitope-specific suppression of the antibody response to Haemophilus influenzae type b conjugate vaccines by preimmunization with vaccine components

    DEFF Research Database (Denmark)

    Barington, T; Skettrup, M; Juul, L

    1993-01-01

    children and adults. Despite its potential importance, the possible influence of preexisting immunity to the components of such conjugates on the vaccination response in humans has been addressed by few studies. To study this issue, we randomized 82 healthy adult volunteers into six groups and vaccinated......Recently, conjugate vaccines containing Haemophilus influenzae type b capsular polysaccharide (HibCP) coupled to protein carriers were introduced for use in infants and certain adult risk groups. Similar conjugate vaccines against other capsulated bacteria are currently under development for both...... and the anti-HibCP immunoglobulin G1 (IgG1) and IgG2 levels were measured before and 4 weeks after the immunizations. For some of the vaccinees, the number of circulating antibody-secreting cells was evaluated 7 days after immunization. Surprisingly, preimmunization with the relevant carrier protein reduced...

  8. Live Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis activate the inflammatory response trhough Toll-like receptors 2, 4, and 9 in species-specific patterns

    DEFF Research Database (Denmark)

    Mogensen, T.H.; Paludan, Søren Riis; Kilian, Mogens

    2006-01-01

    activation by live bacteria. Here, we demonstrate that live Streptococcus pneumoniae, Haemophilus influenzae type b, and Neisseria meningitidis, the three principal causes of bacterial meningitis, use distinct sets of TLRs to trigger the inflammatory response. Using human embryonic kidney 293 cell lines......, each overexpressing one type of TLR, we found that S. pneumoniae triggered activation of the transcription factor nuclear factor-kappaB and expression of interleukin-8, only in cells expressing TLR2 or -9. The same response was evoked by H. influenzae in cells expressing TLR2 or -4 and by N....... meningitidis in cells expressing TLR2, -4, or -9. It is interesting that the ability of S. pneumoniae and N. meningitidis to activate TLR9 was severely attenuated when bacteria had been heat-inactivated prior to stimulation of the cells. In human peripheral blood mononuclear cells, we blocked TLR2, -4, or -9...

  9. Development of a single-tube polymerase chain reaction assay for the simultaneous detection of Haemophilus influenzae, Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus spp. directly in clinical samples.

    Science.gov (United States)

    Xirogianni, Athanasia; Tzanakaki, Georgina; Karagianni, Eleni; Markoulatos, Panayiotis; Kourea-Kremastinou, Jenny

    2009-02-01

    This study describes the development and evaluation of a multiplex single-tube polymerase chain reaction assay for the simultaneous detection of Haemophilus influenzae, Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus spp. used as target species-specific or genus-specific genes. The assay enables the detection of 5 to 50 pg of bacterial DNA. The sensitivity of the assay was evaluated as 100% for P. aeruginosa, S. aureus, and Streptococcus spp., and 94.3% for H. influenzae; the specificity was 100% for all 4 microorganisms (positive predictive value, 100%; negative predictive value, 98.2%). The assay permits rapid and accurate detection of these 4 microorganisms in a wide range of clinical samples such as whole blood, cerebrospinal, ear, pleural and ophthalmic fluids, as well as bronchoalveolar lavage and bronchial secretions.

  10. Risk of febrile seizures and epilepsy after vaccination with diphtheria, tetanus, acellular pertussis, inactivated poliovirus, and Haemophilus influenzae type B.

    Science.gov (United States)

    Sun, Yuelian; Christensen, Jakob; Hviid, Anders; Li, Jiong; Vedsted, Peter; Olsen, Jørn; Vestergaard, Mogens

    2012-02-22

    Vaccination with whole-cell pertussis vaccine carries an increased risk of febrile seizures, but whether this risk applies to the acellular pertussis vaccine is not known. In Denmark, acellular pertussis vaccine has been included in the combined diphtheria-tetanus toxoids-acellular pertussis-inactivated poliovirus-Haemophilus influenzae type b (DTaP-IPV-Hib) vaccine since September 2002. To estimate the risk of febrile seizures and epilepsy after DTaP-IPV-Hib vaccination given at 3, 5, and 12 months. A population-based cohort study of 378,834 children who were born in Denmark between January 1, 2003, and December 31, 2008, and followed up through December 31, 2009; and a self-controlled case series (SCCS) study based on children with febrile seizures during follow-up of the cohort. Hazard ratio (HR) of febrile seizures within 0 to 7 days (0, 1-3, and 4-7 days) after each vaccination and HR of epilepsy after first vaccination in the cohort study. Relative incidence of febrile seizures within 0 to 7 days (0, 1-3, and 4-7 days) after each vaccination in the SCCS study. A total of 7811 children were diagnosed with febrile seizures before 18 months, of whom 17 were diagnosed within 0 to 7 days after the first (incidence rate, 0.8 per 100,000 person-days), 32 children after the second (1.3 per 100,000 person-days), and 201 children after the third (8.5 per 100,000 person-days) vaccinations. Overall, children did not have higher risks of febrile seizures during the 0 to 7 days after the 3 vaccinations vs a reference cohort of children who were not within 0 to 7 days of vaccination. However, a higher risk of febrile seizures was found on the day of the first (HR, 6.02; 95% CI, 2.86-12.65) and on the day of the second (HR, 3.94; 95% CI, 2.18-7.10), but not on the day of the third vaccination (HR, 1.07; 95% CI, 0.73-1.57) vs the reference cohort. On the day of vaccination, 9 children were diagnosed with febrile seizures after the first (5.5 per 100,000 person-days), 12

  11. Haemophilus Influenzae Type b

    Science.gov (United States)

    ... 12 mos.) Toddler 1-3yrs. Preschool 3-5yrs Grade School 5-12yrs. Teen 12-18yrs. Young Adult 18-21yrs. Healthy Living Healthy Living Healthy Living Nutrition Fitness Sports Oral Health Emotional Wellness Growing Healthy Sleep Safety & Prevention Safety & Prevention Safety and Prevention Immunizations ...

  12. Streptococcus pneumoniae and Haemophilus influenzae as etiological agents of conjunctivitis outbreaks in the region of Ribeirão Preto, SP, Brazil

    Directory of Open Access Journals (Sweden)

    Marta I. C. MEDEIROS

    1998-01-01

    Full Text Available In the study of conjunctivitis outbreaks occurring from September 1994 to September 1996 in the region of Ribeirão Preto, conjunctival exudates of 92 patients were cultivated in Instituto Adolfo Lutz Laboratory I, Ribeirão Preto. Most cases occurred in the age range 2-7 years. The etiological agents which were most frequently isolated from the analyzed cases were: Streptococcus pneumoniae and Haemophilus influenzae, in 40.22% and 21.74%, respectively. 51.35% of the S. pneumoniae isolated strains were not typable. The oxacillin-resistant S. pneumoniae strains were submitted to the minimum inhibitory concentration test (MIC and three of them presented intermediate resistance, whereas only one was highly resistant to penicillin.No estudo de surtos de conjuntivite ocorridos no período de setembro de 1994 a setembro de 1996, na região de Ribeirão Preto, foram semeadas no Instituto Adolfo Lutz Laboratório I, Ribeirão Preto, exsudatos conjuntivais de 92 pacientes, sendo que a maioria dos casos estava na faixa etária de 2-7 anos. Os agentes etiológicos mais freqüentemente isolados dos casos analisados foram: Streptococcus pneumoniae e Haemophilus influenzae em 40,22% e 21,74% respectivamente. 51,35% das cepas de S. pneumoniae isoladas foram não tipáveis. As cepas de S. pneumoniae oxacilina resistente foram submetidas ao teste de concentração inibitória mínima (CIM, sendo que três apresentaram resistência intermediária e apenas uma foi altamente resistente à penicilina.

  13. Influence of the beta-lactam resistance phenotype on the cefuroxime versus cefditoren susceptibility of Streptococcus pneumoniae and Haemophilus influenzae recovered from children with acute otitis media.

    Science.gov (United States)

    Fenoll, Asunción; Aguilar, Lorenzo; Robledo, Olga; Giménez, María-José; Tarragó, David; Granizo, Juan-José; Gimeno, Mercedes; Coronel, Pilar

    2007-08-01

    To study the influence of resistance phenotypes (based on sentinel antibiotics: penicillin and amoxicillin with/without clavulanate) on the cefuroxime versus cefditoren susceptibility of Streptococcus pneumoniae and Haemophilus influenzae recovered from children with acute otitis media. Middle ear isolates (193 S. pneumoniae and 114 H. influenzae) received in the Spanish Reference Laboratory (Instituto de Salud Carlos III) were tested. Antimicrobial susceptibility to penicillin, amoxicillin with/without clavulanate, cefuroxime and cefditoren was determined by agar dilution using Mueller-Hinton agar supplemented with 5% sheep blood for S. pneumoniae and Haemophilus Test Medium for H. influenzae. Strains were classified according to penicillin susceptibility (S. pneumoniae) or beta-lactamase production (H. influenzae). The decrease in penicillin susceptibility of S. pneumoniae (from the susceptible to the resistant category) decreased amoxicillin and cefuroxime susceptibility rates from 100% to 34% and 0%, respectively. All pneumococcal strains were inhibited by 0.5 mg/L cefditoren, including those from penicillin-resistant serotypes 14, 23F, 6B and 9V with higher amoxicillin versus penicillin MICs. Susceptibility rates of beta-lactamase-positive H. influenzae strains were 93.8% and 85.4% to amoxicillin/clavulanate and cefuroxime, respectively. Resistance to amoxicillin/clavulanate (MIC>or=8/4 mg/L) was 12.1% (8 out of 66) and 6.3% (3 out of 48) in beta-lactamase-negative and -positive strains, respectively. All H. influenzae strains were inhibited by

  14. Antibacterial activity of Artemisia asiatica essential oil against some common respiratory infection causing bacterial strains and its mechanism of action in Haemophilus influenzae.

    Science.gov (United States)

    Huang, Jiehui; Qian, Chao; Xu, Hongjie; Huang, Yanjie

    2017-12-11

    The main objective of the current study was to investigate the chemical composition of the essential oil of Artemisia asiatica together with investigating the antibacterial effects it exerts on several common respiratory infection causing bacteria including Haemophilus influenzae. Its mechanism of action was studied using various state-of-the-art assays like scanning electron microscopy, DNA, RNA and protein leakage assays, growth curve assays etc. The essential oil was extracted from the leaves of A. asiatica by supercritical CO2 fluid extraction technology. Chemical composition of essential oils was analyzed by gas chromatography-mass-spectrometry (GC-MS). The antibacterial activity was evaluated against 6 bacteria by the paper disc diffusion method. The minimum inhibitory concentration (MIC) and minimum bactericide concentration (MBC) values of the essential oil were estimated by agar dilution method. The antibacterial mechanism was evaluated by growth curve, the integrity of cell membrane and scanning electronmicroscope (SEM). Gas chromatographic analysis of the A. asiatica essential oil led to the identification of 16 chemical constituents accounting for 97.2% of the total oil composition. The major components were found to be Piperitone, (z)-davanone, p-cymene and 1, 8-cineole. The essential oil showed maximum growth inhibition against Haemophilus influenzae with a zone of inhibition of 24.5 mm and MIC/MBC values of 1.9/4.5 mg/mL respectively. Bacteria treated with the essential oil led to a rapid decrease in the number of viable cells. On adding the essential oil of A. asiatica to the bacterial culture, the constituents of the bacterial cell got released into the medium and this cell constituent release increased with increasing doses of the essential oil. SEM showed that the bacterial cells treated with the essential oil showed damaged cell wall, deformed cell morphology and shrunken cells. Copyright © 2017. Published by Elsevier Ltd.

  15. Invasive disease caused by Haemophilus influenzae in Sweden 1997-2009; evidence of increasing incidence and clinical burden of non-type b strains.

    Science.gov (United States)

    Resman, F; Ristovski, M; Ahl, J; Forsgren, A; Gilsdorf, J R; Jasir, A; Kaijser, B; Kronvall, G; Riesbeck, K

    2011-11-01

    Introduction of a conjugated vaccine against encapsulated Haemophilus influenzae type b (Hib) has led to a dramatic reduction of invasive Hib disease. However, an increasing incidence of invasive disease by H. influenzae non-type b has recently been reported. Non-type b strains have been suggested to be opportunists in an invasive context, but information on clinical consequences and related medical conditions is scarce. In this retrospective study, all H. influenzae isolates (n = 410) from blood and cerebrospinal fluid in three metropolitan Swedish regions between 1997 and 2009 from a population of approximately 3 million individuals were identified. All available isolates were serotyped by PCR (n = 250). We observed a statistically significant increase in the incidence of invasive H. influenzae disease, ascribed to non-typeable H. influenzae (NTHi) and encapsulated strains type f (Hif) in mainly individuals >60 years of age. The medical reports from a subset of 136 cases of invasive Haemophilus disease revealed that 48% of invasive NTHi cases and 59% of invasive Hif cases, respectively, met the criteria of severe sepsis or septic shock according to the ACCP/SCCM classification of sepsis grading. One-fifth of invasive NTHi cases and more than one-third of invasive Hif cases were admitted to intensive care units. Only 37% of patients with invasive non-type b disease had evidence of immunocompromise, of which conditions related to impaired humoral immunity was the most common. The clinical burden of invasive non-type b H. influenzae disease, measured as days of hospitalization/100 000 individuals at risk and year, increased significantly throughout the study period. © 2011 The Authors. Clinical Microbiology and Infection © 2011 European Society of Clinical Microbiology and Infectious Diseases.

  16. Invasive Haemophilus influenzae Type b (Hib) Infections in Children with Cancer in the Era of Infant Hib Immunization Programs (1991-2014): A Report from the Canadian Immunization Monitoring Program Active.

    Science.gov (United States)

    McNair, Joanne; Smith, Alyssa; Bettinger, Julie A; Vaudry, Wendy; Tan, Ben; Desai, Shalini; Halperin, Scott A; Top, Karina A

    2017-12-01

    We studied the epidemiology of Haemophilus influenzae type b (Hib) infections among children with cancer admitted to Canadian pediatric hospitals. From 1991-2014, 13 cases among children with cancer were identified through active surveillance. Average age was 6.7 years. Six of 7 cases eligible for infant immunization were age-appropriately immunized (vaccine failures). Children with cancer may benefit from booster Hib immunization.

  17. Isolamento de Haemophiliis aegyptius associado à Febre Purpúrica Brasileira, de cloropídeos (Diptera dos gêneros Hippelates e Liohippelates Isolation of Haemophilus aegyptius associated to Brazilian purpuric fever from Hippelates and Liohippelates flies (Diptera: Chloropidae

    Directory of Open Access Journals (Sweden)

    M. L. C. Tondella

    1994-04-01

    Full Text Available O reconhecimento da Febre Purpúrica Brasileira (FPB, em 1984, originou uma série de estudos que revelaram uma correlação desta doença com conjuntivites causadas por Haemophiliis aegyptius. A associação do aumento de conjuntivites em crianças e a maior densidade populacional de cloropídeos do gênero Hippelates já havia sido verificada desde o século passado. Este fenômeno está relacionado ao tropismo que estes insetos apresentam pelos olhos, secreções e feridas de onde se alimentam. Embora haja evidências do papel destes cloropídeos na transmissão mecânica de conjuntivites bacterianas, o isolamento de Haemophilus aegyptius a partir dos mesmos, no seu habitat natural, ainda não havia sido verificado. No presente trabalho obtivemos o isolamento de cepas invasivas de Haemophilus aegyptius, associadas à FPB, de duas coleções de cloropídeos, classificados como Liohippelates peruanus e uma espécie nova, Hippelates neoproboscideus, coletados ao redor dos olhos de crianças com conjuntivite.The recognition of the Brazilian purpuric fever (BPF in 1984 led to a number of studies which showed a relation between this disease and conjunctivitis caused by Haemophilus aegyptius. The increase in cases of conjunctivitis in children associated with higher population density of eye gnats (Chloropidae: Hippelates has been reported since last century. This phenomenon is related to the attraction that those flies show for the eyes, secretions and wounds, from where they feed on. Although there are evidences on the role of these flies in the mechanical transmission of seasonal bacterial conjunctivitis, the isolation of Haemophilus aegyptius from them in their natural habitat had not been demonstrated yet. In this study Haemophilus aegyptius associated to BPF was isolated from two pools of chloropids collected around the eyes of children with conjuntivitis which were identified as Liohippelates peruanus (Becker and a new species Hippelates

  18. Nasopharyngeal colonization by Haemophilus influenzae in children attending day-care centers, in Ribeirão Preto, State of São Paulo, Brazil Colonização da nasofaringe por Haemophilus influenzae em crianças que freqüentam creches em Ribeirão Preto, Estado de São Paulo, Brasil

    Directory of Open Access Journals (Sweden)

    Maria E.N. Bonifácio da Silva

    2006-03-01

    Full Text Available Nasopharyngeal carriage of Haemophilus influenzae (Hi was studied in 114 healthy children A colonização da nasofaringe por Haemophilus influenzae (Hi foi estudada em 114 crianças saudáveis com menos de 3 anos de idade e que freqüentam creches (day-care centers DCC em Ribeirão Preto, estado de São Paulo, Brasil. Para cada uma das cepas isoladas foram determinados o biótipo, o sorotipo (por antisoro especifico e PCR e a sensibilidade a 14 antibióticos. A freqüência de colonização por Hi foi de 72,0%. As cepas isoladas foram identificadas como pertencentes aos biótipos II (36,5%, I (21,5%, V (18,2% e III (16,1%. A freqüência encontrada de cepas encapsuladas foi de 3,2% para o tipo f, 1,0% para o tipo b, 1,0% para o tipo d e 1,0% para o tipo e. A resistência para trimetoprim-sulfametoxazole e ampicilina foi de 46,2% e 10,7% respectivamente. Resistência múltipla foi encontrada em 14 (15,0% das cepas analisadas. 13,9% das cepas analisadas eram produtoras de beta-lactamase, e não foi recuperada nenhuma cepa beta-lactamase negativa e ampicilina resistente. DCCs são considerados locais de risco, com um alto potencial de disseminação de microrganismos e por isto devem ser continuadamente monitorados com a finalidade de detectar a eliminação da colonização da nasofaringe por cepas H. influenzae tipo b das crianças que freqüentam DCC, ou detectar a sua substituição por outro tipo de cepa.

  19. Patterns of binding of aluminum-containing adjuvants to Haemophilus influenzae type b and meningococcal group C conjugate vaccines and components

    Science.gov (United States)

    Otto, Robert B.D.; Burkin, Karena; Amir, Saba Erum; Crane, Dennis T.; Bolgiano, Barbara

    2015-01-01

    The basis of Haemophilus influenzae type b (Hib) and Neisseria meningitidis serogroup C (MenC) glycoconjugates binding to aluminum-containing adjuvants was studied. By measuring the amount of polysaccharide and protein in the non-adsorbed supernatant, the adjuvant, aluminum phosphate, AlPO4, was found to be less efficient than aluminum hydroxide, Al(OH)3 at binding to the conjugates, at concentrations relevant to licensed vaccine formulations and when equimolar. At neutral pH, binding of TT conjugates to AlPO4 was facilitated through the carrier protein, with only weak binding of AlPO4 to CRM197 being observed. There was slightly higher binding of either adjuvant to tetanus toxoid conjugates, than to CRM197 conjugates. This was verified in AlPO4 formulations containing DTwP–Hib, where the adsorption of TT-conjugated Hib was higher than CRM197-conjugated Hib. At neutral pH, the anionic Hib and MenC polysaccharides did not appreciably bind to AlPO4, but did bind to Al(OH)3, due to electrostatic interactions. Phosphate ions reduced the binding of the conjugates to the adjuvants. These patterns of adjuvant adsorption can form the basis for future formulation studies with individual and combination vaccines containing saccharide-protein conjugates. PMID:26194164

  20. First comparison of adjuvant for trivalent inactivated Haemophilus parasuis serovars 4, 5 and 12 vaccines against Glässer's disease.

    Science.gov (United States)

    Xue, Qiao; Zhao, Zhanqin; Liu, Huisheng; Chen, Kunpeng; Xue, Yun; Wang, Le

    2015-12-15

    Haemophilus parasuis has had a huge impact in the swine industry throughout the world. Inactivated bacterium for H. parasuis is a traditional vaccine that can elicit efficient protection against homologous challenges. The objective of this study was to screen for the adjuvant-enhanced immune effect of trivalent inactivated H. parasuis serovars 4, 5 and 12 (prevalent serovars in China) vaccines against Glässer's disease. The adjuvants of mineral oil, aluminum hydroxide, Montanide GEL 01 PR, Montanide IMS 1313N VG and Montanide ISA 760 VG were used to make emulsified inactivated H. parasuis serovars 4, 5 and 12, respectively. Safety, antibody titer and protective efficacy of these vaccines were examined separately in piglets, and the feasibility of microagglutination test for detecting antibody titer of H. parasuis was confirmed for the first time. Due to easy of injection, high safety, rapidly immune responses, high concentrations of antibody, and 100% of protective efficacy for piglets, Montanide GEL 01 PR adjuvant can provide more homologous serovar protection than other domestically developed inactivated vaccines and should be used as a candidate adjuvant. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Recent trends in pediatric bacterial meningitis in Japan--a country where Haemophilus influenzae type b and Streptococcus pneumoniae conjugated vaccines have just been introduced.

    Science.gov (United States)

    Shinjoh, Masayoshi; Iwata, Satoshi; Yagihashi, Tatsuhiko; Sato, Yoshitake; Akita, Hironobu; Takahashi, Takao; Sunakawa, Keisuke

    2014-08-01

    To investigate the trends in incidence and the characteristics of bacterial meningitis in Japan where Haemophilus influenzae type b (Hib) vaccine and 7-valent pneumococcal conjugated vaccine (PCV7) were introduced in 2008 and 2010, respectively, which was 5-20 years after their introduction in western countries. The nationwide Japanese survey of pediatric and neonatal bacterial meningitis was performed in 2011 and 2012. We analyzed the epidemiological and clinical data, and compared the information obtained in the previous nationwide survey database. We also investigated the risk factors for disease outcome. In the 2011-2012 surveys, 357 patients were evaluated. H. influenzae, Streptococcus pneumoniae, Streptococcus agalactiae and Escherichia coli were the main organisms. The number of patients hospitalized with bacterial meningitis per 1000 admissions decreased from 1.31 in 2009 to 0.43 in 2012 (p meningitis also decreased from 0.66 to 0.08 (p bacterial meningitis. Earlier introduction of these vaccines may have prevented bacterial meningitis among Japanese children. Copyright © 2014 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  2. Bacterial meningitis in Malawian adults, adolescents, and children during the era of antiretroviral scale-up and Haemophilus influenzae type b vaccination, 2000-2012.

    Science.gov (United States)

    Wall, Emma C; Everett, Dean B; Mukaka, Mavuto; Bar-Zeev, Naor; Feasey, Nicholas; Jahn, Andreas; Moore, Mike; van Oosterhout, Joep J; Pensalo, Paul; Baguimira, Kenneth; Gordon, Stephen B; Molyneux, Elizabeth M; Carrol, Enitan D; French, Neil; Molyneux, Malcolm E; Heyderman, Robert S

    2014-05-01

    We documented bacterial meningitis trends among adults and children presenting to a large teaching hospital in Malawi during introduction of Haemophilus influenzae type b (Hib) vaccination and the rollout of antiretroviral therapy (ART). We analyzed data from 51 000 consecutive cerebrospinal fluid (CSF) samples obtained from adults, adolescents, and children with suspected meningitis admitted to the Queen Elizabeth Central Hospital, Blantyre, Malawi, between 2000 and 2012. There was a significant decline in the total number of CSF isolates over 12 years (incident rate ratio [IRR], 0.93; 95% CI, .92-.94; P bacterial meningitis in 2012 was 20 per 100,000 cases in children aged bacterial meningitis have declined in children, but not adults, coinciding with the introduction of Hib vaccination. The highly successful rollout of ART has not yet resulted in a reduction in the incidence in adults where the burden remains high. Long-term surveillance of bacterial meningitis outside of the epidemic "meningitis belt" in Africa is essential.

  3. Encapsulated pleural effusion due to Haemophilus influenzae biotype II in a child with trisomy 21: A case report and literature review.

    Science.gov (United States)

    Kaneko, Masanori; Bando, Yuki; Fujita, Tomohiro; Hirose, Yoneji; Suganuma, Eisuke; Ishii, Masahiro; Takahashi, Takashi

    2017-01-01

    Haemophilus influenzae (Hi) can colonize in the upper respiratory tract and cause severe pulmonary infections, especially among immunocompromised children. Herein, we report a case of left encapsulated pleural effusion (EPE) due to Hi in a 24-month-old girl with trisomy 21. She was already vaccinated against Hi type b. The Hi biotype II was isolated from both the blood and aspirated sputum obtained upon admission. Ampicillin/sulbactam 180 mg/kg/day was administered intravenously for 34 days with oxygen supplementation for 4 days. She clinically recovered without undergoing thoracic drainage. One month after discharge, the girl developed acute otitis media, and the throat swab was cultured. Nontypeable Hi with the same biotype II was isolated, and the infection was controlled by administering antimicrobials. In this report, a literature review regarding the EPE due to Hi in children is also summarized. Pediatric clinicians should be aware of the possibility of Hi-related EPE because of its rapid progression, although it is rare in clinical settings. In addition, they need to consider the possibility of repetitive respiratory infections with Hi in a child with trisomy 21.

  4. NadN and e (P4) are essential for utilization of NAD and nicotinamide mononucleotide but not nicotinamide riboside in Haemophilus influenzae.

    Science.gov (United States)

    Kemmer, G; Reilly, T J; Schmidt-Brauns, J; Zlotnik, G W; Green, B A; Fiske, M J; Herbert, M; Kraiss, A; Schlör, S; Smith, A; Reidl, J

    2001-07-01

    Haemophilus influenzae has an absolute requirement for NAD (factor V) because it lacks almost all the biosynthetic enzymes necessary for the de novo synthesis of that cofactor. Factor V can be provided as either nicotinamide adenosine dinucleotide (NAD), nicotinamide mononucleotide (NMN), or nicotinamide riboside (NR) in vitro, but little is known about the source or the mechanism of uptake of these substrates in vivo. As shown by us earlier, at least two gene products are involved in the uptake of NAD, the outer membrane lipoprotein e (P4), which has phosphatase activity and is encoded by hel, and a periplasmic NAD nucleotidase, encoded by nadN. It has also been observed that the latter gene product is essential for H. influenzae growth on media supplemented with NAD. In this report, we describe the functions and substrates of these two proteins as they act together in an NAD utilization pathway. Data are provided which indicate that NadN harbors not only NAD pyrophosphatase but also NMN 5'-nucleotidase activity. The e (P4) protein is also shown to have NMN 5'-nucleotidase activity, recognizing NMN as a substrate and releasing NR as its product. Insertion mutants of nadN or deletion and site-directed mutants of hel had attenuated growth and a reduced uptake phenotype when NMN served as substrate. A hel and nadN double mutant was only able to grow in the presence of NR, whereas no uptake of NMN was observed.

  5. Invasive Haemophilus influenzae type b disease in England and Wales: who is at risk after 2 decades of routine childhood vaccination?

    Science.gov (United States)

    Collins, Sarah; Ramsay, Mary; Campbell, Helen; Slack, Mary P E; Ladhani, Shamez N

    2013-12-01

    The introduction of the Haemophilus influenzae serotype b (Hib) conjugate vaccine into national immunization has led to rapid and sustained declines in invasive Hib disease incidence across all age groups. In industrialized countries with established Hib vaccination programs, however, little is known about individuals who develop invasive Hib disease. This study describes the epidemiology of invasive Hib disease in England and Wales during 2000-2012 and the clinical characteristics of laboratory-confirmed Hib cases diagnosed during 2009-2012. Public Health England (PHE) conducts enhanced national surveillance of invasive Hib disease in England and Wales. Detailed clinical information was obtained for all laboratory-confirmed Hib cases diagnosed during 2009-2012. Invasive Hib disease in England and Wales has been declining since 2002, reaching its lowest incidence of 0.02 per 100 000 (14 cases) in 2012. In children aged Wales is currently the best that has been achieved since the introduction of routine Hib vaccination in 1992. Invasive Hib disease is no longer a major cause of acute bacterial meningitis in children but, instead, cases are more likely to present as pneumonia in older adults with comorbidities, similar to the less virulent nonencapsulated H. influenzae.

  6. Antibody response to the Haemophilus influenzae type b-tetanus toxoid conjugate vaccine in healthy and infection-prone individuals with IgG3 subclass deficiency.

    Science.gov (United States)

    Hahn-Zoric, M; Ulanova, M; Friman, V; Björkander, J; Oxelius, V A; Lucas, A; Hanson, L A

    2004-09-01

    Searching for a possible explanation for the phenotypic heterogeneity in IgG3 deficiency, we studied the antibody response to a polysaccharide and a protein antigen in IgG3-deficient (IgG3d) adults after vaccination with Haemophilus influenzae type b capsular polysaccharide (Hib CP) conjugated to tetanus toxoid. Distribution of isotypes, idiotypes, clonotypes, and Gm allotypes were compared. All the vaccinated individuals, irrespective of the level of IgG3 and proneness to infections, developed protective levels of anti-Hib CP. Significantly lower prevaccination levels of IgG2 (p infection-prone compared to the healthy IgG3d individuals and/or controls. Seventy percent of the IgG3d patients and none of the controls had the low responding Gm(ga-n/ga-n) genotype, while the majority of the controls had the alternative Gm(bfn/bfn) genotype. The conjugate ACT-HIB vaccine efficiently overcomes the IgG3 subclass deficiency state and the genetic predisposition for lower responsiveness, providing protection against Hib and tetanus infections. The proneness to infection in some IgG3d individuals may relate to their low prevaccination antibody levels.

  7. Sequence analysis of serotype-specific synthesis regions II of Haemophilus influenzae serotypes c and d: evidence for common ancestry of capsule synthesis in Pasteurellaceae and Neisseria meningitidis.

    Science.gov (United States)

    Lâm, Thiên-Trí; Claus, Heike; Frosch, Matthias; Vogel, Ulrich

    2011-06-01

    Sequencing of yet unknown Haemophilus influenzae serotype c (Hic) and d (Hid) capsule synthesis regions II revealed four (ccs1-4) and five (dcs1-5) open reading frames, respectively. The inferred gene functions were in line with capsular polysaccharide structures. One or more proteins encoded by the Hic capsule synthesis region II showed similarity to Actinobacillus pleuropneumoniae serotype 1 and Actinobacillus suis K1 enzymes. Orthologues to the complete operon were observed in Actinobacillus minor strain 202, where even the gene order was conserved. Furthermore, Ccs4 was related to the capsule O-acetyltransferase of Neisseria meningitidis serogroup W-135. For the Hid locus, similarities to Hie, Mannheimia haemolytica A1 and N. meningitidis serogroup A were identified and the succession of genes was similar in the different species. The resemblance of genes and gene organization found for Hic and Hid with other species suggested horizontal gene transfer during capsule evolution across the bacterial classes. Copyright © 2011 Institut Pasteur. Published by Elsevier SAS. All rights reserved.

  8. Trend in Antibiotic Resistance of Streptococcus Pneumoniae and Haemophilus Influenzae Strains Isolated from Community Acquired Respiratory Tract Infections in Dakar, Senegal Between 2005 and 2008

    Directory of Open Access Journals (Sweden)

    A. Guèye Ndiaye

    2010-05-01

    Full Text Available Development of antibiotic resistance among common respiratory pathogens is a major cause of concern worldwide. Streptococcus pneumoniae and Haemophilus influenzae are among the most common respiratory pathogens. In this study, representative samples obtained from 3 different medical centers in Dakar, Senegal were subjected to antibiotic susceptibility testing. The samples were collected from 2005 to 2008 and the data obtained was compared to establish resistance patterns between the two years (i.e. 2005–2006 to 2007–2008. S. pneumoniae exhibited a significant increase in the resistance to azithromycin and the intermediate susceptibility to penicillin G and cotrimoxazole. H. influenzae also exhibited a significant increase in resistance to azithromycin and intermediate susceptibility to chloramphenicol. None of H. influenzae samples were resistant to amoxicillin/clavulanic acid, cephalosporin and fluroquinolones and most of the S. pneumoniae isolates demonstrated high susceptibility to the antibiotics tested. Results from this study will provide greater insights to antibiotic therapy during respiratory tract infections in Dakar, Senegal. This study also establishes the importance of continuous monitoring of antibiotic susceptibility patterns that are often region-specific.

  9. Development of a diagnostic real-time polymerase chain reaction assay for the detection of invasive Haemophilus influenzae in clinical samples.

    LENUS (Irish Health Repository)

    Meyler, Kenneth L

    2012-12-01

    Since the introduction of the Haemophilus influenzae serotype b vaccine, invasive H. influenzae disease has become dominated by nontypeable (NT) strains. Several widely used molecular diagnostic methods have been shown to lack sensitivity or specificity in the detection of some of these strains. Novel real-time assays targeting the fucK, licA, and ompP2 genes were developed and evaluated. The fucK assay detected all strains of H. influenzae tested (n = 116) and had an analytical sensitivity of 10 genome copies\\/polymerase chain reaction (PCR). This assay detected both serotype b and NT H. influenzae in 12 previously positive specimens (culture and\\/or bexA PCR) and also detected H. influenzae in a further 5 of 883 culture-negative blood and cerebrospinal fluid (CSF) samples. The fucK assay has excellent potential as a diagnostic test for detection of typeable and nontypeable strains of invasive H. influenzae in clinical samples of blood and CSF.

  10. Moraxella catarrhalis Outer Membrane Vesicles Carry β-Lactamase and Promote Survival of Streptococcus pneumoniae and Haemophilus influenzae by Inactivating Amoxicillin▿

    Science.gov (United States)

    Schaar, Viveka; Nordström, Therése; Mörgelin, Matthias; Riesbeck, Kristian

    2011-01-01

    Moraxella catarrhalis is a common pathogen found in children with upper respiratory tract infections and in patients with chronic obstructive pulmonary disease during exacerbations. The bacterial species is often isolated together with Streptococcus pneumoniae and Haemophilus influenzae. Outer membrane vesicles (OMVs) are released by M. catarrhalis and contain phospholipids, adhesins, and immunomodulatory compounds such as lipooligosaccharide. We have recently shown that M. catarrhalis OMVs exist in patients upon nasopharyngeal colonization. As virtually all M. catarrhalis isolates are β-lactamase positive, the goal of this study was to investigate whether M. catarrhalis OMVs carry β-lactamase and to analyze if OMV consequently can prevent amoxicillin-induced killing. Recombinant β-lactamase was produced and antibodies were raised in rabbits. Transmission electron microscopy, flow cytometry, and Western blotting verified that OMVs carried β-lactamase. Moreover, enzyme assays revealed that M. catarrhalis OMVs contained active β-lactamase. OMVs (25 μg/ml) incubated with amoxicillin for 1 h completely hydrolyzed amoxicillin at concentrations up to 2.5 μg/ml. In functional experiments, preincubation of amoxicillin (10× MIC) with M. catarrhalis OMVs fully rescued amoxicillin-susceptible M. catarrhalis, S. pneumoniae, and type b or nontypeable H. influenzae from β-lactam-induced killing. Our results suggest that the presence of amoxicillin-resistant M. catarrhalis originating from β-lactamase-containing OMVs may pave the way for respiratory pathogens that by definition are susceptible to β-lactam antibiotics. PMID:21576428

  11. Epidemiology of paediatric meningitis in central Côte d'Ivoire after the implementation of Haemophilus influenzae type b vaccination.

    Science.gov (United States)

    Touré, Fidèle S; Kouame, Samson; Tia, Honoré; Monemo, Pacôme; Cissé, Amadou; Diané, Bamourou; Becker, Sören L; Akoua-Koffi, Chantal

    2017-07-01

    Infectious meningitis accounts for enormous morbidity worldwide, but there is a paucity of data on its regional epidemiology in resource-constrained settings of sub-Saharan Africa. Here, we present a study on the aetiology of paediatric meningitis in central Côte d'Ivoire. Between June 2012 and December 2013, all cerebrospinal fluid (CSF) samples drawn at the University Teaching Hospital Bouaké were examined for the presence of bacterial and fungal pathogens. A causative agent was detected in 31 out of 833 CSF specimens (3.7%), with the most prevalent pathogens being Streptococcus pneumoniae (n=15) and Neisseria meningitidis (n=5). With the exception of neonates, these two bacteria were the most common agents in all age groups. Of note, only a single case of Haemophilus influenzae meningitis was detected. Hence, this study reports a considerable shift in the epidemiology of paediatric meningitis in central Côte d'Ivoire. Following the implementation of a nation-wide childhood vaccination programme against H. influenzae type b, this pathogen was much less frequently reported than in previous studies. The integration of specific vaccines against S. pneumoniae and N. meningitidis into the childhood vaccination programme in Côted'Ivoire holds promise to further reduce the burden due to infectious meningitis.

  12. Nontypeable Haemophilus influenzae-Induced MyD88 Short Expression Is Regulated by Positive IKKβ and CREB Pathways and Negative ERK1/2 Pathway

    Science.gov (United States)

    Andrews, Carla S.; Miyata, Masanori; Susuki-Miyata, Seiko; Lee, Byung-Cheol; Komatsu, Kensei; Li, Jian-Dong

    2015-01-01

    Airway diseases such as asthma and chronic obstructive pulmonary disease (COPD) are characterized by excessive inflammation and are exacerbated by nontypeable Haemophilus influenzae (NTHi). Airway epithelial cells mount the initial innate immune responses to invading pathogens and thus modulate inflammation. While inflammation is necessary to eliminate a pathogen, excessive inflammation can cause damage to the host tissue. Therefore, the inflammatory response must be tightly regulated and deciphering the signaling pathways involved in this response will enhance our understanding of the regulation of the host inflammatory response. NTHi binds to TLR2 and signal propagation requires the adaptor molecule myeloid differentiation factor 88 (MyD88). An alternative spliced form of MyD88 is called MyD88 short (MyD88s) and has been identified in macrophages and embryonic cell lines as a negative regulator of inflammation. However, the role of MyD88s in NTHi-induced inflammation in airway epithelial cells remains unknown. Here we show that NTHi induces MyD88s expression and MyD88s is a negative regulator of inflammation in airway epithelial cells. We further demonstrate that MyD88s is positively regulated by IKKβ and CREB and negatively regulated by ERK1/2 signaling pathways. Taken together these data indicate that airway inflammation is controlled in a negative feedback manner involving MyD88s and suggest that airway epithelial cells are essential to maintain immune homeostasis. PMID:26669856

  13. Patterns of binding of aluminum-containing adjuvants to Haemophilus influenzae type b and meningococcal group C conjugate vaccines and components.

    Science.gov (United States)

    Otto, Robert B D; Burkin, Karena; Amir, Saba Erum; Crane, Dennis T; Bolgiano, Barbara

    2015-09-01

    The basis of Haemophilus influenzae type b (Hib) and Neisseria meningitidis serogroup C (MenC) glycoconjugates binding to aluminum-containing adjuvants was studied. By measuring the amount of polysaccharide and protein in the non-adsorbed supernatant, the adjuvant, aluminum phosphate, AlPO4, was found to be less efficient than aluminum hydroxide, Al(OH)3 at binding to the conjugates, at concentrations relevant to licensed vaccine formulations and when equimolar. At neutral pH, binding of TT conjugates to AlPO4 was facilitated through the carrier protein, with only weak binding of AlPO4 to CRM197 being observed. There was slightly higher binding of either adjuvant to tetanus toxoid conjugates, than to CRM197 conjugates. This was verified in AlPO4 formulations containing DTwP-Hib, where the adsorption of TT-conjugated Hib was higher than CRM197-conjugated Hib. At neutral pH, the anionic Hib and MenC polysaccharides did not appreciably bind to AlPO4, but did bind to Al(OH)3, due to electrostatic interactions. Phosphate ions reduced the binding of the conjugates to the adjuvants. These patterns of adjuvant adsorption can form the basis for future formulation studies with individual and combination vaccines containing saccharide-protein conjugates. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  14. Nonencapsulated or nontypeable Haemophilus influenzae are more likely than their encapsulated or serotypeable counterparts to have mutations in their fucose operon.

    Science.gov (United States)

    Shuel, Michelle L; Karlowsky, Kathleen E; Law, Dennis K S; Tsang, Raymond S W

    2011-12-01

    Population biology of Haemophilus influenzae can be studied by multilocus sequence typing (MLST), and isolates are assigned sequence types (STs) based on nucleotide sequence variations in seven housekeeping genes, including fucK. However, the ST cannot be assigned if one of the housekeeping genes is absent or cannot be detected by the current protocol. Occasionally, strains of H. influenzae have been reported to lack the fucK gene. In this study, we examined the prevalence of this mutation among our collection of H. influenzae isolates. Of the 704 isolates studied, including 282 encapsulated and 422 nonencapsulated isolates, nine were not typeable by MLST owing to failure to detect the fucK gene. All nine fucK-negative isolates were nonencapsulated and belonged to various biotypes. DNA sequencing of the fucose operon region confirmed complete deletion of genes in the operon in seven of the nine isolates, while in the remaining two isolates, some of the genes were found intact or in parts. The significance of these findings is discussed.

  15. Development of a diagnostic real-time polymerase chain reaction assay for the detection of invasive Haemophilus influenzae in clinical samples.

    Science.gov (United States)

    Meyler, Kenneth L; Meehan, Mary; Bennett, Desiree; Cunney, Robert; Cafferkey, Mary

    2012-12-01

    Since the introduction of the Haemophilus influenzae serotype b vaccine, invasive H. influenzae disease has become dominated by nontypeable (NT) strains. Several widely used molecular diagnostic methods have been shown to lack sensitivity or specificity in the detection of some of these strains. Novel real-time assays targeting the fucK, licA, and ompP2 genes were developed and evaluated. The fucK assay detected all strains of H. influenzae tested (n = 116) and had an analytical sensitivity of 10 genome copies/polymerase chain reaction (PCR). This assay detected both serotype b and NT H. influenzae in 12 previously positive specimens (culture and/or bexA PCR) and also detected H. influenzae in a further 5 of 883 culture-negative blood and cerebrospinal fluid (CSF) samples. The fucK assay has excellent potential as a diagnostic test for detection of typeable and nontypeable strains of invasive H. influenzae in clinical samples of blood and CSF. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Evaluation of the repertoire of the TonB-dependent receptors of Haemophilus ducreyi for their role in virulence in humans.

    Science.gov (United States)

    Leduc, Isabelle; Banks, Keith E; Fortney, Kate R; Patterson, Kristine B; Billings, Steve D; Katz, Barry P; Spinola, Stanley M; Elkins, Christopher

    2008-04-15

    Haemophilus ducreyi contains 3 TonB-dependent receptors: the hemoglobin receptor HgbA, which is required for virulence in humans; the heme receptor TdhA; and an uncharacterized conserved hypothetical protein TdX (HD0646). A double tdX/tdhA mutant (FX527) was constructed on the background of a human-passaged variant of strain 35000 (35000HP). Six volunteers were infected with 35000HP at 3 sites on one arm and with FX527 at 3 sites on the other. The pustule formation rate was 55.6% (95% confidence interval [CI], 35.7%-75.4%) at 18 parent-strain sites and 44.4% (95% CI, 15.0%-73.9%) at 18 mutant-strain sites (P = .51). Similar amounts of 35000HP and FX527 were recovered from pustules in semiquantitative culture. Thus, TdX and TdhA are not necessary for virulence, whereas HgbA is both necessary and sufficient for virulence in humans. The data suggest that hemoglobin is the sole source of heme/iron used by H. ducreyi in vivo and has implications for the potential of HgbA as a vaccine.

  17. Temporal association of infant immunisation with pneumococcal conjugate vaccine on the ecology of Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus nasopharyngeal colonisation in a rural South African community.

    Science.gov (United States)

    Nzenze, S A; Shiri, T; Nunes, M C; Klugman, K P; Kahn, K; Twine, R; de Gouveia, L; von Gottberg, A; Madhi, S A

    2014-09-22

    Immunisation of children with pneumococcal conjugate vaccines (PCV) may affect the bacterial-ecology of the nasopharynx, including colonisation by Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus. The aim of this study was to evaluate the effect of infant PCV-immunisation on the nasopharyngeal ecology of these potentially pathogenic bacteria in a rural African setting. Two cross sectional surveys were undertaken from May to October in 2009 (Period-1) which coincided with the introduction of 7-valent PCV (PCV7) and in May-October 2011 (Period-2). Consenting household members, where there was a child 12 years, the prevalence of colonisation decreased from 11.2% to 6.8%, 16.7% to 8.8% and 31.2% to 23.7% for S. pneumoniae, H. influenzae and S. aureus, respectively; p<0.001 for all comparions. Synergistic relationships for S. aureus with H. influenzae and S. pneumoniae were observed in both periods among this group. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Immunoglobulin A Protease Variants Facilitate Intracellular Survival in Epithelial Cells By Nontypeable Haemophilus influenzae That Persist in the Human Respiratory Tract in Chronic Obstructive Pulmonary Disease.

    Science.gov (United States)

    Murphy, Timothy F; Kirkham, Charmaine; Gallo, Mary C; Yang, Yang; Wilding, Gregory E; Pettigrew, Melinda M

    2017-12-05

    Nontypeable Haemophilus influenzae (NTHi) persists in the airways in chronic obstructive pulmonary disease (COPD). NTHi expresses 4 immunoglobulin (Ig)A protease variants (A1, A2, B1, B2) with distinct cleavage specificities for human IgA1. Little is known about the different roles of IgA protease variants in NTHi infection. Twenty-six NTHi isolates from a 20-year longitudinal study of COPD were analyzed for IgA protease expression, survival in human respiratory epithelial cells, and cleavage of lysosomal-associated membrane protein 1 (LAMP1). IgA protease B1 and B2-expressing strains showed greater intracellular survival in host epithelial cells than strains expressing no IgA protease (P protease A1 or A2 (P protease expression showed reduced survival in host cells compared with the same strain that expressed IgA protease B1 (P = .006) or B2 (P = .015). IgA proteases B1 and B2 cleave LAMP1. Passage of strains through host cells selected for expression of IgA proteases B1 and B2 but not A1. IgA proteases B1 and B2 cleave LAMP1 and mediate intracellular survival in respiratory epithelial cells. Intracellular persistence of NTHi selects for expression of IgA proteases B1 and B2. The variants of NTHi IgA proteases play distinct roles in pathogenesis of infection.

  19. Computer-assisted 2-D agarose electrophoresis of Haemophilus influenzae type B meningitis vaccines and analysis of polydisperse particle populations in the size range of viruses: a review.

    Science.gov (United States)

    Tietz, Dietmar

    2007-02-01

    When protein-polysaccharide conjugated vaccines were first developed for the immunization of small children against meningitis caused by infection with Haemophilus influenzae type b (Hib), the vaccine preparations varied in immunogenicity. Testing for immunogenicity was time-consuming and alternative analytical procedures for determining vaccine quality were unsatisfactory. For example, due to the very high molecular weight of the vaccine particles, immunogens could only be physically characterized as a fraction in the void volume of Sepharose gel filtration. In search of better analytical methods, a computer-assisted electrophoretic technique for analyzing such vaccines was developed in the period from 1983 to 1995. This new approach made it possible to analyze highly negatively charged particles as large as or larger than intact viruses. 2-D gel patterns were generated that varied depending on the conditions of the particular vaccine preparation and were therefore characteristic of each vaccine sample. Thus, vaccine particle populations with a continuous size variation over a wide range (polydisperse) could be characterized according to size and free mobility (related to particle surface net charge density). These advances are reviewed in this article, since the developed methods are still a promising tool for vaccine quality control and for predicting immunogen effectiveness in the production of vaccines. The technique is potentially beneficial for Hib immunogens and other high-molecular-mass vaccines. Additional biomedical applications for this nondenaturing electrophoretic technique are briefly discussed and detailed information about computational and mathematical procedures and theoretical aspects is provided in the Appendices.

  20. Origin of the diversity in DNA recognition domains in phasevarion associated modA genes of pathogenic Neisseria and Haemophilus influenzae.

    Science.gov (United States)

    Gawthorne, Jayde A; Beatson, Scott A; Srikhanta, Yogitha N; Fox, Kate L; Jennings, Michael P

    2012-01-01

    Phase variable restriction-modification (R-M) systems have been identified in a range of pathogenic bacteria. In some it has been demonstrated that the random switching of the mod (DNA methyltransferase) gene mediates the coordinated expression of multiple genes and constitutes a phasevarion (phase variable regulon). ModA of Neisseria and Haemophilus influenzae contain a highly variable, DNA recognition domain (DRD) that defines the target sequence that is modified by methylation and is used to define modA alleles. 18 distinct modA alleles have been identified in H. influenzae and the pathogenic Neisseria. To determine the origin of DRD variability, the 18 modA DRDs were used to search the available databases for similar sequences. Significant matches were identified between several modA alleles and mod gene from distinct bacterial species, indicating one source of the DRD variability was via horizontal gene transfer. Comparison of DRD sequences revealed significant mosaicism, indicating exchange between the Neisseria and H. influenzae modA alleles. Regions of high inter- and intra-allele similarity indicate that some modA alleles had undergone recombination more frequently than others, generating further diversity. Furthermore, the DRD from some modA alleles, such as modA12, have been transferred en bloc to replace the DRD from different modA alleles.

  1. Origin of the Diversity in DNA Recognition Domains in Phasevarion Associated modA Genes of Pathogenic Neisseria and Haemophilus influenzae

    Science.gov (United States)

    Gawthorne, Jayde A.; Beatson, Scott A.; Srikhanta, Yogitha N.; Fox, Kate L.; Jennings, Michael P.

    2012-01-01

    Phase variable restriction-modification (R-M) systems have been identified in a range of pathogenic bacteria. In some it has been demonstrated that the random switching of the mod (DNA methyltransferase) gene mediates the coordinated expression of multiple genes and constitutes a phasevarion (phase variable regulon). ModA of Neisseria and Haemophilus influenzae contain a highly variable, DNA recognition domain (DRD) that defines the target sequence that is modified by methylation and is used to define modA alleles. 18 distinct modA alleles have been identified in H. influenzae and the pathogenic Neisseria. To determine the origin of DRD variability, the 18 modA DRDs were used to search the available databases for similar sequences. Significant matches were identified between several modA alleles and mod gene from distinct bacterial species, indicating one source of the DRD variability was via horizontal gene transfer. Comparison of DRD sequences revealed significant mosaicism, indicating exchange between the Neisseria and H. influenzae modA alleles. Regions of high inter- and intra-allele similarity indicate that some modA alleles had undergone recombination more frequently than others, generating further diversity. Furthermore, the DRD from some modA alleles, such as modA12, have been transferred en bloc to replace the DRD from different modA alleles. PMID:22457715

  2. Absceso cerebral por Haemophilus influenzae serotipo e en un paciente pediátrico con síndrome de Apert

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    Adela M Isasmendi

    2014-12-01

    Full Text Available Se presenta el caso de un absceso cerebral causado por Haemophilus influenzae tipo e, en un paciente de 12 años con síndrome de Apert. El síndrome de Apert se caracteriza por el cierre prematuro de las suturas craneales. En 2010, el paciente presentó traumatismo craneano en región frontal, fractura y fístula de líquido cefalorraquídeo. En febrero de 2013 consultó por fiebre, vómitos y convulsión tónica clónica generalizada, con deterioro progresivo del sensorio. La tomografía axial computarizada mostró una lesión frontal derecha, edema perilesional, leve dilatación ventricular y pansinusitis. Se diagnosticó absceso cerebral con pioventriculitis y se realizó drenaje. Se obtuvo desarrollo de un cocobacilo gram negativo, que fue identificado como H. influenzae serotipo e. Se realizó tratamiento empírico con meropenem (120 mg/kg/día y vancomicina (60 mg/kg/día. Luego del resultado del cultivo, se rotó a ceftriaxona (100 mg/kg/día y metronidazol (500 mg/8 h. El paciente cumplió 8 semanas de tratamiento y se observó evolución favorable.

  3. Fastidious Gram-Negatives: Identification by the Vitek 2 Neisseria-Haemophilus Card and by Partial 16S rRNA Gene Sequencing Analysis.

    Science.gov (United States)

    Sönksen, Ute Wolff; Christensen, Jens Jørgen; Nielsen, Lisbeth; Hesselbjerg, Annemarie; Hansen, Dennis Schrøder; Bruun, Brita

    2010-12-31

    Taxonomy and identification of fastidious Gram negatives are evolving and challenging. We compared identifications achieved with the Vitek 2 Neisseria-Haemophilus (NH) card and partial 16S rRNA gene sequence (526 bp stretch) analysis with identifications obtained with extensive phenotypic characterization using 100 fastidious Gram negative bacteria. Seventy-five strains represented 21 of the 26 taxa included in the Vitek 2 NH database and 25 strains represented related species not included in the database. Of the 100 strains, 31 were the type strains of the species. Vitek 2 NH identification results: 48 of 75 database strains were correctly identified, 11 strains gave `low discrimination´, seven strains were unidentified, and nine strains were misidentified. Identification of 25 non-database strains resulted in 14 strains incorrectly identified as belonging to species in the database. Partial 16S rRNA gene sequence analysis results: For 76 strains phenotypic and sequencing identifications were identical, for 23 strains the sequencing identifications were either probable or possible, and for one strain only the genus was confirmed. Thus, the Vitek 2 NH system identifies most of the commonly occurring species included in the database. Some strains of rarely occurring species and strains of non-database species closely related to database species cause problems. Partial 16S rRNA gene sequence analysis performs well, but does not always suffice, additional phenotypical characterization being useful for final identification.

  4. Passive immunization with a polyclonal antiserum to the hemoglobin receptor of Haemophilus ducreyi confers protection against a homologous challenge in the experimental swine model of chancroid.

    Science.gov (United States)

    Leduc, Isabelle; Fusco, William G; Choudhary, Neelima; Routh, Patty A; Cholon, Deborah M; Hobbs, Marcia M; Almond, Glen W; Orndorff, Paul E; Elkins, Christopher

    2011-08-01

    Haemophilus ducreyi, the etiologic agent of chancroid, has an obligate requirement for heme. Heme is acquired by H. ducreyi from its human host via TonB-dependent transporters expressed at its bacterial surface. Of 3 TonB-dependent transporters encoded in the genome of H. ducreyi, only the hemoglobin receptor, HgbA, is required to establish infection during the early stages of the experimental human model of chancroid. Active immunization with a native preparation of HgbA (nHgbA) confers complete protection in the experimental swine model of chancroid, using either Freund's or monophosphoryl lipid A as adjuvants. To determine if transfer of anti-nHgbA serum is sufficient to confer protection, a passive immunization experiment using pooled nHgbA antiserum was conducted in the experimental swine model of chancroid. Pigs receiving this pooled nHgbA antiserum were protected from a homologous, but not a heterologous, challenge. Passively transferred polyclonal antibodies elicited to nHgbA bound the surface of H. ducreyi and partially blocked hemoglobin binding by nHgbA, but were not bactericidal. Taken together, these data suggest that the humoral immune response to the HgbA vaccine is protective against an H. ducreyi infection, possibly by preventing acquisition of the essential nutrient heme.

  5. Passive Immunization with a Polyclonal Antiserum to the Hemoglobin Receptor of Haemophilus ducreyi Confers Protection against a Homologous Challenge in the Experimental Swine Model of Chancroid▿

    Science.gov (United States)

    Leduc, Isabelle; Fusco, William G.; Choudhary, Neelima; Routh, Patty A.; Cholon, Deborah M.; Hobbs, Marcia M.; Almond, Glen W.; Orndorff, Paul E.; Elkins, Christopher

    2011-01-01

    Haemophilus ducreyi, the etiologic agent of chancroid, has an obligate requirement for heme. Heme is acquired by H. ducreyi from its human host via TonB-dependent transporters expressed at its bacterial surface. Of 3 TonB-dependent transporters encoded in the genome of H. ducreyi, only the hemoglobin receptor, HgbA, is required to establish infection during the early stages of the experimental human model of chancroid. Active immunization with a native preparation of HgbA (nHgbA) confers complete protection in the experimental swine model of chancroid, using either Freund's or monophosphoryl lipid A as adjuvants. To determine if transfer of anti-nHgbA serum is sufficient to confer protection, a passive immunization experiment using pooled nHgbA antiserum was conducted in the experimental swine model of chancroid. Pigs receiving this pooled nHgbA antiserum were protected from a homologous, but not a heterologous, challenge. Passively transferred polyclonal antibodies elicited to nHgbA bound the surface of H. ducreyi and partially blocked hemoglobin binding by nHgbA, but were not bactericidal. Taken together, these data suggest that the humoral immune response to the HgbA vaccine is protective against an H. ducreyi infection, possibly by preventing acquisition of the essential nutrient heme. PMID:21646451

  6. Medium wave exposure characterisation using exposure quotients.

    Science.gov (United States)

    Paniagua, Jesús M; Rufo, Montaña; Jiménez, Antonio; Antolín, Alicia; Pinar, Iván

    2010-06-01

    One of the aspects considered in the International Commission on Non-Ionizing Radiation Protection guidelines is that, in situations of simultaneous exposure to fields of different frequencies, exposure quotients for thermal and electrical stimulation effects should be examined. The aim of the present work was to analyse the electromagnetic radiation levels and exposure quotients for exposure to multiple-frequency sources in the vicinity of medium wave radio broadcasting antennas. The measurements were made with a spectrum analyser and a monopole antenna. Kriging interpolation was used to prepare contour maps and to estimate the levels in the towns and villages of the zone. The results showed that the exposure quotient criterion based on electrical stimulation effects to be more stringent than those based on thermal effects or power density levels. Improvement of dosimetry evaluations requires the spectral components of the radiation to be quantified, followed by application of the criteria for exposure to multiple-frequency sources.

  7. Rapid discrimination of Haemophilus influenzae, H. parainfluenzae, and H. haemolyticus by fluorescence in situ hybridization (FISH) and two matrix-assisted laser-desorption-ionization time-of-flight mass spectrometry (MALDI-TOF-MS) platforms.

    Science.gov (United States)

    Frickmann, Hagen; Christner, Martin; Donat, Martina; Berger, Anja; Essig, Andreas; Podbielski, Andreas; Hagen, Ralf Matthias; Poppert, Sven

    2013-01-01

    Due to considerable differences in pathogenicity, Haemophilus influenzae, H. parainfluenzae and H. haemolyticus have to be reliably discriminated in routine diagnostics. Retrospective analyses suggest frequent misidentifications of commensal H. haemolyticus as H. influenzae. In a multi-center approach, we assessed the suitability of fluorescence in situ hybridization (FISH) and matrix-assisted laser-desorption-ionization time-of-flight mass-spectrometry (MALDI-TOF-MS) for the identification of H. influenzae, H. parainfluenzae and H. haemolyticus to species level. A strain collection of 84 Haemophilus spp. comprising 50 H. influenzae, 25 H. parainfluenzae, 7 H. haemolyticus, and 2 H. parahaemolyticus including 77 clinical isolates was analyzed by FISH with newly designed DNA probes, and two different MALDI-TOF-MS systems (Bruker, Shimadzu) with and without prior formic acid extraction. Among the 84 Haemophilus strains analyzed, FISH led to 71 correct results (85%), 13 uninterpretable results (15%), and no misidentifications. Shimadzu MALDI-TOF-MS resulted in 59 correct identifications (70%), 19 uninterpretable results (23%), and 6 misidentifications (7%), using colony material applied directly. Bruker MALDI-TOF-MS with prior formic acid extraction led to 74 correct results (88%), 4 uninterpretable results (5%) and 6 misidentifications (7%). The Bruker MALDI-TOF-MS misidentifications could be resolved by the addition of a suitable H. haemolyticus reference spectrum to the system's database. In conclusion, no analyzed diagnostic procedure was free of errors. Diagnostic results have to be interpreted carefully and alternative tests should be applied in case of ambiguous test results on isolates from seriously ill patients.

  8. Sensibilidad antibiótica de cepas de Haemophilus spp aisladas de pacientes pediátricos en un hospital general entre los años 2003 -2006.

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    Raúl Rodrigo Alarco Castro

    2008-04-01

    Full Text Available Objetivo: Determinar la sensibilidad antibiótica de cepas de Haemophilus spp aisladas de pacientes pediátricos en un hospital general entre los años 2003 y 2006. Materiales y métodos: Estudio descriptivo retrospectivo en el que se incluyeron cultivos positivos de Haemophilus spp. Se revisaron las historias clínicas de los pacientes de los cuales provenían los cultivos. Resultados: Se encontraron 37 cultivos positivos para Haemophilus spp, entre los cuales se encontró mayor sensibilidad a levofloxacino (100%, ampicilina/sulbactam (92%, carbapenems (95% y ciprofloxacino (85%. La sensibilidad a los antibióticos más usados contra esta bacteria fue menor: ampicilina (73%, ceftriaxona (77%, cloramfenicol (78% y azitromicina (62%. Se comparó la resistencia de las cepas que causaron neumonía y meningoencefalitis, encontrándose similar sensibilidad a lo ya presentado. En relación a los factores asociados a resistencia a antibióticos específicos no se encontró diferencias importantes por tratarse de grupos pequeños, pues de los 37 cultivos, sólo se encontraron 18 historias clínicas. Conclusión: La resistencia a antibióticos de primera línea (ampicilina y cloramfenicol es baja. Ampicilina/sulbactam es el antibiótico que presentó menor resistencia. Se necesitan estudios más amplios para determinar factores asociados a resistencia. (Rev Med Hered 2008;19

  9. Comparison of Established Diagnostic Methodologies and a Novel Bacterial smpB Real-Time PCR Assay for Specific Detection of Haemophilus influenzae Isolates Associated with Respiratory Tract Infections.

    Science.gov (United States)

    Reddington, Kate; Schwenk, Stefan; Tuite, Nina; Platt, Gareth; Davar, Danesh; Coughlan, Helena; Personne, Yoann; Gant, Vanya; Enne, Virve I; Zumla, Alimuddin; Barry, Thomas

    2015-09-01

    Haemophilus influenzae is a significant causative agent of respiratory tract infections (RTI) worldwide. The development of a rapid H. influenzae diagnostic assay that would allow for the implementation of infection control measures and also improve antimicrobial stewardship for patients is required. A number of nucleic acid diagnostics approaches that detect H. influenzae in RTIs have been described in the literature; however, there are reported specificity and sensitivity limitations for these assays. In this study, a novel real-time PCR diagnostic assay targeting the smpB gene was designed to detect all serogroups of H. influenzae. The assay was validated using a panel of well-characterized Haemophilus spp. Subsequently, 44 Haemophilus clinical isolates were collected, and 36 isolates were identified as H. influenzae using a gold standard methodology that combined the results of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and a fucK diagnostic assay. Using the novel smpB diagnostic assay, 100% concordance was observed with the gold standard, demonstrating a sensitivity of 100% (95% confidence interval [CI], 90.26% to 100.00%) and a specificity of 100% (95% CI, 63.06% to 100.00%) when used on clinical isolates. To demonstrate the clinical utility of the diagnostic assay presented, a panel of lower RTI samples (n = 98) were blindly tested with the gold standard and smpB diagnostic assays. The results generated were concordant for 94/98 samples tested, demonstrating a sensitivity of 90.91% (95% CI, 78.33% to 97.47%) and a specificity of 100% (95% CI, 93.40% to 100.00%) for the novel smpB assay when used directly on respiratory specimens. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  10. Enfermedad invasora por Haemophilus Influenzae antes y después de la campaña de vacunación en la población infantil de la Comunidad Valenciana (1996-2000

    Directory of Open Access Journals (Sweden)

    Goicoechea Sáez Mercedes

    2002-01-01

    Full Text Available Fundamento: La introducción de la vacuna conjugada anti Haemophilus influenzae tipo b (Hib en niños ha provocado un llamativo descenso de la incidencia de la enfermedad por H. influenzae. El objetivo de este estudio es analizar las características más relevantes de la enfermedad invasora por H. influenzae en cuanto a la epidemiología, clínica, evolución y estado de vacunación de la población infantil de la Comunidad Valenciana en el periodo 1996-2000. Método: Los datos se recogen de las historias clínicas de los niños menores de 15 años que hayan presentado síntomas y signos clínicos sugestivos de enfermedad invasora con aislamiento de Haemophilus influenzae y/o que cumple con los criterios de definición de caso establecidos, atendidos en todos los hospitales públicos de la Comunidad Valenciana entre 1996 y 2000. La evolución de la incidencia se valoró mediante tasas de incidencia. La clínica y su evolución (secuelas y letalidad mediante la frecuencia y distribución por edad. Resultados: Se registraron un total de 36 casos de enfermedad invasora por Haemophilus influenzae. La tasa de incidencia en niños menores de 15 años pasó de 3,56/10(5 en 1996 a 1,07/10(5 en 1997 (coincidiendo con la campaña de vacunación y la posterior inclusión de la vacuna conjugada anti Hib en el Calendario de Vacunaciones Sistemáticas de la Comunidad Valenciana y 0,30/10(5 en 1998, situación que se sigue manteniendo en los años posteriores. El 53% de los casos se dan en menores de 18 meses. Tanto las secuelas como los fallecimientos se producen en la época anterior a la aplicación rutinaria de la vacuna conjugada. Ningún niño vacunado correctamente falleció. Se registraron 2 casos de H. influenzae tipo no b en niños vacunados. Conclusiones: La incidencia de la infección por Haemophilus influenzae tipo b disminuyó drásticamente desde el inicio de la vacunación sistemática de la población infantil.

  11. ENFERMEDAD INVASORA POR HAEMOPHILUS INFLUENZAE ANTES Y DESPUÉS DE LA CAMPAÑA DE VACUNACIÓN EN LA POBLACIÓN INFANTIL DE LA COMUNIDAD VALENCIANA (1996-2000

    Directory of Open Access Journals (Sweden)

    Mercedes Goicoechea Sáez

    2002-01-01

    Full Text Available Fundamento: La introducción de la vacuna conjugada anti Haemophilus influenzae tipo b (Hib en niños ha provocado un llamativo descenso de la incidencia de la enfermedad por H. influenzae. El objetivo de este estudio es analizar las características más relevantes de la enfermedad invasora por H. influenzae en cuanto a la epidemiología, clínica, evolución y estado de vacunación de la población infantil de la Comunidad Valenciana en el periodo 1996-2000. Método: Los datos se recogen de las historias clínicas de los niños menores de 15 años que hayan presentado síntomas y signos clínicos sugestivos de enfermedad invasora con aislamiento de Haemophilus influenzae y/o que cumple con los criterios de definición de caso establecidos, atendidos en todos los hospitales públicos de la Comunidad Valenciana entre 1996 y 2000. La evolución de la incidencia se valoró mediante tasas de incidencia. La clínica y su evolución (secuelas y letalidad mediante la frecuencia y distribución por edad. Resultados: Se registraron un total de 36 casos de enfermedad invasora por Haemophilus influenzae. La tasa de incidencia en niños menores de 15 años pasó de 3,56/105 en 1996 a 1,07/105 en 1997 (coincidiendo con la campaña de vacunación y la posterior inclusión de la vacuna conjugada anti Hib en el Calendario de Vacunaciones Sistemáticas de la Comunidad Valenciana y 0,30/105 en 1998, situación que se sigue manteniendo en los años posteriores. El 53% de los casos se dan en menores de 18 meses. Tanto las secuelas como los fallecimientos se producen en la época anterior a la aplicación rutinaria de la vacuna conjugada. Ningún niño vacunado correctamente falleció. Se registraron 2 casos de H. influenzae tipo no b en niños vacunados. Conclusiones: La incidencia de la infección por Haemophilus influenzae tipo b disminuyó drásticamente desde el inicio de la vacunación sistemática de la población infantil.

  12. Biochemical characterization of TyrA enzymes from Ignicoccus hospitalis and Haemophilus influenzae: A comparative study of the bifunctional and monofunctional dehydrogenase forms.

    Science.gov (United States)

    Shlaifer, Irina; Quashie, Peter Kojo; Kim, Hyun Young; Turnbull, Joanne L

    2017-03-01

    Biosynthesis of l-tyrosine (l-Tyr) is directed by the interplay of two enzymes. Chorismate mutase (CM) catalyzes the rearrangement of chorismate to prephenate, which is then converted to hydroxyphenylpyruvate by prephenate dehydrogenase (PD). This work reports the first characterization of the independently expressed PD domain of bifunctional CM-PD from the crenarchaeon Ignicoccus hospitalis and the first functional studies of both full-length CM-PD and the PD domain from the bacterium Haemophilus influenzae. All proteins were hexa-histidine tagged, expressed in Escherichia coli and purified. Expression and purification of I. hospitalis CM-PD generated a degradation product identified as a PD fragment lacking the protein's first 80 residues, Δ80CM-PD. A comparable stable PD domain could also be generated by limited tryptic digestion of this bifunctional enzyme. Thus, Δ80CM-PD constructs were prepared in both organisms. CM-PD and Δ80CM-PD from both organisms were dimeric and displayed the predicted enzymatic activities and thermal stabilities in accord with their hyperthermophilic and mesophilic origins. In contrast with H. influenzae PD activity which was NAD+-specific and displayed >75% inhibition with 50μM l-Tyr, I. hospitalis PD demonstrated dual cofactor specificity with a preference for NADP+ and an insensitivity to l-Tyr. These properties are consistent with a model of the I. hospitalis PD domain based on the previously reported structure of the H. influenzae homolog. Our results highlight the similarities and differences between the archaeal and bacterial TyrA proteins and reveal that the PD activity of both prokaryotes can be successfully mapped to a functionally independent unit. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Colonization Density of the Upper Respiratory Tract as a Predictor of Pneumonia-Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus, and Pneumocystis jirovecii.

    Science.gov (United States)

    Park, Daniel E; Baggett, Henry C; Howie, Stephen R C; Shi, Qiyuan; Watson, Nora L; Brooks, W Abdullah; Deloria Knoll, Maria; Hammitt, Laura L; Kotloff, Karen L; Levine, Orin S; Madhi, Shabir A; Murdoch, David R; O'Brien, Katherine L; Scott, J Anthony G; Thea, Donald M; Ahmed, Dilruba; Antonio, Martin; Baillie, Vicky L; DeLuca, Andrea N; Driscoll, Amanda J; Fu, Wei; Gitahi, Caroline W; Olutunde, Emmanuel; Higdon, Melissa M; Hossain, Lokman; Karron, Ruth A; Maiga, Abdoul Aziz; Maloney, Susan A; Moore, David P; Morpeth, Susan C; Mwaba, John; Mwenechanya, Musaku; Prosperi, Christine; Sylla, Mamadou; Thamthitiwat, Somsak; Zeger, Scott L; Feikin, Daniel R

    2017-06-15

    There is limited information on the association between colonization density of upper respiratory tract colonizers and pathogen-specific pneumonia. We assessed this association for Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus, and Pneumocystis jirovecii. In 7 low- and middle-income countries, nasopharyngeal/oropharyngeal swabs from children with severe pneumonia and age-frequency matched community controls were tested using quantitative polymerase chain reaction (PCR). Differences in median colonization density were evaluated using the Wilcoxon rank-sum test. Density cutoffs were determined using receiver operating characteristic curves. Cases with a pathogen identified from lung aspirate culture or PCR, pleural fluid culture or PCR, blood culture, and immunofluorescence for P. jirovecii defined microbiologically confirmed cases for the given pathogens. Higher densities of H. influenzae were observed in both microbiologically confirmed cases and chest radiograph (CXR)-positive cases compared to controls. Staphylococcus aureus and P. jirovecii had higher densities in CXR-positive cases vs controls. A 5.9 log10 copies/mL density cutoff for H. influenzae yielded 86% sensitivity and 77% specificity for detecting microbiologically confirmed cases; however, densities overlapped between cases and controls and positive predictive values were poor (<3%). Informative density cutoffs were not found for S. aureus and M. catarrhalis, and a lack of confirmed case data limited the cutoff identification for P. jirovecii. There is evidence for an association between H. influenzae colonization density and H. influenzae-confirmed pneumonia in children; the association may be particularly informative in epidemiologic studies. Colonization densities of M. catarrhalis, S. aureus, and P. jirovecii are unlikely to be of diagnostic value in clinical settings.

  14. Haemophilus influenzae bla(ROB-1) mutations in hypermutagenic deltaampC Escherichia coli conferring resistance to cefotaxime and beta-lactamase inhibitors and increased susceptibility to cefaclor.

    Science.gov (United States)

    Galán, Juan-Carlos; Morosini, María-Isabel; Baquero, María-Rosario; Reig, Milagro; Baquero, Fernando

    2003-08-01

    The clinical use of cefaclor has been shown to enrich Haemophilus influenzae populations harboring cefaclor-hydrolyzing ROB-1 beta-lactamase. Such a selective process may lead to the increased use of extended-spectrum cephalosporins or beta-lactams plus beta-lactamase inhibitors and, eventually, resistance to these agents, which has not previously been observed in H. influenzae. In order to establish which bla(ROB-1) mutations, if any, could confer resistance to extended-spectrum cephalosporins and/or to beta-lactamase inhibitors, a plasmid harboring bla(ROB-1) was transformed into hypermutagenic strain Escherichia coli GB20 (DeltaampC mutS::Tn10), and this construct was used in place of H. influenzae bla(ROB-1). Strain GB20 with the cloned gene was submitted to serial passages in tubes containing broth with increasing concentrations of selected beta-lactams (cefotaxime or amoxicillin-clavulanate). Different mutations in the bla(ROB-1) gene were obtained during the passages in the presence of the different concentrations of the selective agents. Mutants resistant to extended-spectrum cephalosporins harbored either the Leu169-->Ser169 or the Arg164-->Trp164 substitution or the double amino acid change Arg164-->Trp164 and Ala237-->Thr237. ROB-1 mutants that were resistant to beta-lactams plus beta-lactamase inhibitors and that harbored the Arg244-->Cys244 or the Ser130-->Gly130 replacement were also obtained. The cefaclor-hydrolyzing efficiencies of the ROB-1 variants were strongly decreased in all mutants, suggesting that if bla(ROB-1) mutants were selected by cefaclor, this drug would prevent the further evolution of this beta-lactamase toward molecular forms able to resist extended-spectrum cephalosporins or beta-lactamase inhibitors.

  15. IgG responses to Pneumococcal and Haemophilus influenzae protein antigens are not impaired in children with a history of recurrent acute otitis media.

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    Selma P Wiertsema

    Full Text Available BACKGROUND: Vaccines including conserved antigens from Streptococcus pneumoniae and nontypeable Haemophilus influenzae (NTHi have the potential to reduce the burden of acute otitis media. Little is known about the antibody response to such antigens in young children with recurrent acute otitis media, however, it has been suggested antibody production may be impaired in these children. METHODS: We measured serum IgG levels against 4 pneumococcal (PspA1, PspA 2, CbpA and Ply and 3 NTHi (P4, P6 and PD proteins in a cross-sectional study of 172 children under 3 years of age with a history of recurrent acute otitis media (median 7 episodes, requiring ventilation tube insertion and 63 healthy age-matched controls, using a newly developed multiplex bead assay. RESULTS: Children with a history of recurrent acute otitis media had significantly higher geometric mean serum IgG levels against NTHi proteins P4, P6 and PD compared with healthy controls, whereas there was no difference in antibody levels against pneumococcal protein antigens. In both children with and without a history of acute otitis media, antibody levels increased with age and were significantly higher in children colonised with S. pneumoniae or NTHi compared with children that were not colonised. CONCLUSIONS: Proteins from S. pneumoniae and NTHi induce serum IgG in children with a history of acute otitis media. The mechanisms in which proteins induce immunity and potential protection requires further investigation but the dogma of impaired antibody responses in children with recurrent acute otitis media should be reconsidered.

  16. Characterization of the N-Acetyl-5-neuraminic Acid-binding Site of the Extracytoplasmic Solute Receptor (SiaP) of Nontypeable Haemophilus influenzae Strain 2019

    Energy Technology Data Exchange (ETDEWEB)

    Johnston, Jason W.; Coussens, Nathan P.; Allen, Simon; Houtman, Jon C.D.; Turner, Keith H.; Zaleski, Anthony; Ramaswamy, S.; Gibson, Bradford W.; Apicella, Michael A. (Iowa); (Buck Inst.)

    2012-11-14

    Nontypeable Haemophilus influenzae is an opportunistic human pathogen causing otitis media in children and chronic bronchitis and pneumonia in patients with chronic obstructive pulmonary disease. The outer membrane of nontypeable H. influenzae is dominated by lipooligosaccharides (LOS), many of which incorporate sialic acid as a terminal nonreducing sugar. Sialic acid has been demonstrated to be an important factor in the survival of the bacteria within the host environment. H. influenzae is incapable of synthesizing sialic acid and is dependent on scavenging free sialic acid from the host environment. To achieve this, H. influenzae utilizes a tripartite ATP-independent periplasmic transporter. In this study, we characterize the binding site of the extracytoplasmic solute receptor (SiaP) from nontypeable H. influenzae strain 2019. A crystal structure of N-acetyl-5-neuraminic acid (Neu5Ac)-bound SiaP was determined to 1.4 {angstrom} resolution. Thermodynamic characterization of Neu5Ac binding shows this interaction is enthalpically driven with a substantial unfavorable contribution from entropy. This is expected because the binding of SiaP to Neu5Ac is mediated by numerous hydrogen bonds and has several buried water molecules. Point mutations targeting specific amino acids were introduced in the putative binding site. Complementation with the mutated siaP constructs resulted either in full, partial, or no complementation, depending on the role of specific residues. Mass spectrometry analysis of the O-deacylated LOS of the R127K point mutation confirmed the observation of reduced incorporation of Neu5Ac into the LOS. The decreased ability of H. influenzae to import sialic acid had negative effects on resistance to complement-mediated killing and viability of biofilms in vitro, confirming the importance of sialic acid transport to the bacterium.

  17. Internalization and trafficking of nontypeable Haemophilus influenzae in human respiratory epithelial cells and roles of IgA1 proteases for optimal invasion and persistence.

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    Clementi, Cara F; Håkansson, Anders P; Murphy, Timothy F

    2014-01-01

    Nontypeable Haemophilus influenzae (NTHI) is a leading cause of opportunistic infections of the respiratory tract in children and adults. Although considered an extracellular pathogen, NTHI has been observed repeatedly within and between cells of the human respiratory tract, and these observations have been correlated to symptomatic infection. These findings are intriguing in light of the knowledge that NTHI persists in the respiratory tract despite antibiotic therapy and the development of bactericidal antibodies. We hypothesized that intracellular NTHI avoids, escapes, or neutralizes the endolysosomal pathway and persists within human respiratory epithelial cells and that human IgA1 proteases are required for optimal internalization and persistence of NTHI. Virtually all strains encode a human IgA1 protease gene, igaA, and we previously characterized a novel human IgA1 protease gene, igaB, that is associated with disease-causing strains and is homologous to the IgA1 protease that is unique to pathogenic Neisseria spp. Here, we show that NTHI invades human bronchial epithelial cells in vitro in a lipid raft-independent manner, is subsequently trafficked via the endolysosomal pathway, and is killed in lysosomes after variable durations of persistence. IgaA is required for optimal invasion. IgaB appears to play little or no role in adherence or invasion but is required for optimal intracellular persistence of NTHI. IgaB cleaves lysosome-associated membrane protein 1 (LAMP1) at pHs characteristic of the plasma membrane, early endosome, late endosome, and lysosome. However, neither IgA1 protease inhibits acidification of intracellular vesicles containing NTHI. NTHI IgA1 proteases play important but different roles in NTHI invasion and trafficking in respiratory epithelial cells.

  18. NOD2/RICK-dependent β-defensin 2 regulation is protective for nontypeable Haemophilus influenzae-induced middle ear infection.

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    Jeong-Im Woo

    Full Text Available Middle ear infection, otitis media (OM, is clinically important due to the high incidence in children and its impact on the development of language and motor coordination. Previously, we have demonstrated that the human middle ear epithelial cells up-regulate β-defensin 2, a model innate immune molecule, in response to nontypeable Haemophilus influenzae (NTHi, the most common OM pathogen, via TLR2 signaling. NTHi does internalize into the epithelial cells, but its intracellular trafficking and host responses to the internalized NTHi are poorly understood. Here we aimed to determine a role of cytoplasmic pathogen recognition receptors in NTHi-induced β-defensin 2 regulation and NTHi clearance from the middle ear. Notably, we observed that the internalized NTHi is able to exist freely in the cytoplasm of the human epithelial cells after rupturing the surrounding membrane. The human middle ear epithelial cells inhibited NTHi-induced β-defensin 2 production by NOD2 silencing but augmented it by NOD2 over-expression. NTHi-induced β-defensin 2 up-regulation was attenuated by cytochalasin D, an inhibitor of actin polymerization and was enhanced by α-hemolysin, a pore-forming toxin. NOD2 silencing was found to block α-hemolysin-mediated enhancement of NTHi-induced β-defensin 2 up-regulation. NOD2 deficiency appeared to reduce inflammatory reactions in response to intratympanic inoculation of NTHi and inhibit NTHi clearance from the middle ear. Taken together, our findings suggest that a cytoplasmic release of internalized NTHi is involved in the pathogenesis of NTHi infections, and NOD2-mediated β-defensin 2 regulation contributes to the protection against NTHi-induced otitis media.

  19. The impact of residency and urbanicity on Haemophilus influenzae Type b and pneumococcal immunization in Shanghai Children: a Retrospective Cohort Study.

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    Abram L Wagner

    Full Text Available BACKGROUND: Haemophilus influenzae type b (Hib vaccine and pneumococcal conjugate vaccine (PCV are relatively expensive, newly introduced vaccines in China. This study evaluates the impact of residency and urbanicity on Hib vaccine and PCV coverage for children aged 2 to 7 years living in Shanghai, China, in August 2012. METHODS: In this exploratory cohort study, a sample of children aged 2 to 7 years, all of whom were eligible to have received the complete series of Hib vaccine and PCV, was obtained from the Shanghai Immunization Program Information System. Three measures of vaccination coverage for Hib vaccine and PCV were examined: dose 1 coverage, series completion, and timeliness of dose 1 vaccination. Multivariable binomial regression was used to estimate the difference in vaccination coverage between locals and the floating population. RESULTS: Dose 1 coverage was 50.9% for Hib vaccine and 11.4% for PCV for the 28,141 abstracted pediatric records. For both vaccines, dose 1 coverage was higher in locals than in the floating population. The disparity in coverage between locals and the floating population was greater in suburban areas than urban areas. Of all children who received dose 1, 79.7% completed the Hib vaccine series, and 91.3% completed the PCV series. Timely dose 1 coverage was 8.2% for Hib vaccine and 0.5% for PCV. CONCLUSION: Low vaccination coverage and extremely low levels of timely dose 1 vaccination indicate that current vaccination efforts are inadequate to reduce the burden of Hib and pneumococcal disease among Chinese children, especially infants. Government funding of the Hib vaccine and PCV through the Expanded Program on Immunization would increase uptake and could also ensure that improvement in the timeliness of administration and series completion is targeted for all demographic groups.

  20. Gene Content and Diversity of the Loci Encoding Biosynthesis of Capsular Polysaccharides of the 15 Serovar Reference Strains of Haemophilus parasuis

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    Weinert, Lucy A.; Luan, Shi-Lu; Peters, Sarah E.; Chaudhuri, Roy R.; Harris, David; Angen, Øystein; Aragon, Virginia; Parkhill, Julian; Langford, Paul R.; Rycroft, Andrew N.; Wren, Brendan W.; Tucker, Alexander W.; Maskell, Duncan J.

    2013-01-01

    Haemophilus parasuis is the causative agent of Glässer's disease, a systemic disease of pigs, and is also associated with pneumonia. H. parasuis can be classified into 15 different serovars. Here we report, from the 15 serotyping reference strains, the DNA sequences of the loci containing genes for the biosynthesis of the group 1 capsular polysaccharides, which are potential virulence factors of this bacterium. We contend that these loci contain genes for polysaccharide capsule structures, and not a lipopolysaccharide O antigen, supported by the fact that they contain genes such as wza, wzb, and wzc, which are associated with the export of polysaccharide capsules in the current capsule classification system. A conserved region at the 3′ end of the locus, containing the wza, ptp, wzs, and iscR genes, is consistent with the characteristic export region 1 of the model group 1 capsule locus. A potential serovar-specific region (region 2) has been found by comparing the predicted coding sequences (CDSs) in all 15 loci for synteny and homology. The region is unique to each reference strain with the exception of those in serovars 5 and 12, which are identical in terms of gene content. The identification and characterization of this locus among the 15 serovars is the first step in understanding the genetic, molecular, and structural bases of serovar specificity in this poorly studied but important pathogen and opens up the possibility of developing an improved molecular serotyping system, which would greatly assist diagnosis and control of Glässer's disease. PMID:23873912

  1. Identification of the Functional Initiation Codons of a Phase-Variable Gene of Haemophilus influenzae, lic2A, with the Potential for Differential Expression▿

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    Dixon, Kevin; Bayliss, Christopher D.; Makepeace, Katherine; Moxon, E. Richard; Hood, Derek W.

    2007-01-01

    Simple sequence repeats located within reading frames mediate phase-variable ON/OFF switches in gene expression by generating frameshifts. Multiple translation initiation codons in different reading frames are found upstream of most Haemophilus influenzae tetranucleotide repeat tracts, raising the possibility of multiple active reading frames and more than two levels of gene expression for these loci. Phase variation between three levels of gene expression (strong, weak, and none) was observed when lic2A was fused to a lacZ reporter gene. The lic2A 5′ CAAT repeat tract is preceded by four 5′ ATG codons (x, y, z1, and z2) in two reading frames. Each of these initiation codons was inactivated by site-directed mutagenesis. Strong expression from frame 1 was associated with x but not y. Weak expression from frame 2 was mainly dependent on the z2 codon, and there was no expression from frame 3. Using monoclonal antibodies specific for a digalactoside epitope of lipopolysaccharide whose synthesis requires Lic2A, two levels (strong and undetectable) of antibody reactivity were detected, suggesting that weak expression of lic2A is not discernible at the phenotypic level. Inactivation of the x initiation codon resulted in loss of strong expression of the digalactoside epitope and elevated killing by human serum. The failure to detect more than two phenotypes for lic2A, despite clear evidence of weak expression from the z1/z2 initiation codons, leaves open the question of whether or not multiple initiation codons are associated with more complex patterns of phenotypic variation rather than classical phase-variable switching between two phenotypes. PMID:17098909

  2. Budget impact analysis of vaccination against Haemophilus influenzae type b as a part of a Pentavalent vaccine in the childhood immunization schedule of Iran.

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    Teimouri, Fatemeh; Kebriaeezadeh, Abbas; Zahraei, Seyed Mohsen; Gheiratian, MohammadMahdi; Nikfar, Shekoufeh

    2017-01-14

    Health decision makers need to know the impact of the development of a new intervention on the public health and health care costs so that they can plan for economic and financial objectives. The aim of this study was to determine the budget impact of adding Haemophilus influenzae type b (Hib) as a part of a Pentavalent vaccine (Hib-HBV-DTP) to the national childhood immunization schedule of Iran. An excel-based model was developed to determine the costs of including the Pentavalent vaccine in the national immunization program (NIP), comparing the present schedule with the previous one (including separate DTP and hepatitis B vaccines). The total annual costs included the cost of vaccination (the vaccine and syringe) and the cost of Hib treatment. The health outcome was the estimated annual cases of the diseases. The net budget impact was the difference in the total annual cost between the two schedules. Uncertainty about the vaccine effectiveness, vaccination coverage, cost of the vaccine, and cost of the diseases were handled through scenario analysis. The total cost of vaccination during 5 years was $18,060,463 in the previous program and $67,774,786 in the present program. Inclusion of the Pentavalent vaccine would increase the vaccination cost about $49 million, but would save approximately $6 million in the healthcare costs due to reduction of disease cases and treatment costs. The introduction of the Pentavalent vaccine resulted in a net increase in the healthcare budget expenditure across all scenarios from $43.4 million to $50.7 million. The results of this study showed that the inclusion of the Pentavalent vaccine in the NIP of Iran had a significant impact on the health care budget and increased the financial burden on the government. Budget impact of including Pentavalent vaccine in the national immunization schedule of Iranᅟ.

  3. Immunoinformatics Approach in Designing Epitope-based Vaccine Against Meningitis-inducing Bacteria (Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae Type b).

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    Zahroh, Hilyatuz; Ma'rup, Ahmad; Tambunan, Usman Sumo Friend; Parikesit, Arli Aditya

    2016-01-01

    Meningitis infection is one of the major threats during Hajj season in Mecca. Meningitis vaccines are available, but their uses are limited in some countries due to religious reasons. Furthermore, they only give protection to certain serogroups, not to all types of meningitis-inducing bacteria. Recently, research on epitope-based vaccines has been developed intensively. Such vaccines have potential advantages over conventional vaccines in that they are safer to use and well responded to the antibody. In this study, we developed epitope-based vaccine candidates against various meningitis-inducing bacteria, including Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae type b. The epitopes were selected from their protein of polysaccharide capsule. B-cell epitopes were predicted by using BCPred, while T-cell epitope for major histocompatibility complex (MHC) class I was predicted using PAProC, TAPPred, and Immune Epitope Database. Immune Epitope Database was also used to predict T-cell epitope for MHC class II. Population coverage and molecular docking simulation were predicted against previously generated epitope vaccine candidates. The best candidates for MHC class I- and class II-restricted T-cell epitopes were MQYGDKTTF, MKEQNTLEI, ECTEGEPDY, DLSIVVPIY, YPMAMMWRNASNRAI, TLQMTLLGIVPNLNK, ETSLHHIPGISNYFI, and SLLYILEKNAEMEFD, which showed 80% population coverage. The complexes of class I T-cell epitopes-HLA-C*03:03 and class II T-cell epitopes-HLA-DRB1*11:01 showed better affinity than standards as evaluated from their ΔGbinding value and the binding interaction between epitopes and HLA molecules. These peptide constructs may further be undergone in vitro and in vivo testings for the development of targeted vaccine against meningitis infection.

  4. VACCINE IMMUNIZATION FOR PREVENTION OF PNEUMOCOCCAL, HAEMOPHILUS INFLUENZAE AND FLU AMONG SICKLY CHILDREN, WHO OFTEN SUFFER FROM PERSISTENT HETEROSPECIFIC INFECTIOUS PATHOLOGY OF THE BRONCHOPULMONARY SYSTEM

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    L.I. Ilienko

    2006-01-01

    Full Text Available Among serious diseases of the lower respiratory tract a special place is taken by pneumonias and chronic infectious respiratory diseases caused by pneumococcus and Haemophilus influenzae type b (HIB. The research purpose is to determine the effectiveness of vaccine combined application to treat sickly children, who often suffer from persistent infectious pathology of the respiratory tract, for flu, pneumococcal and HIB disease. 110 children aged between 3 and 12 have been vaccinated. The first part of research implied children vaccination by means of Actahib and Pneumo 23 vaccines (Sanofi Pasteur, France, the second one consisted in immunization of children with the same pathology by means of Pneumo 23, Actahib and Vaxigrip vaccines (Sanofi Pasteur, France. The researches established that within a year after HIB and Pneumo 23 vaccination the frequency of upper and lower respiratory tract acerbations reduced by 2,3 times on average; likewise, the number of system antimicrobial dosage reduced by 7,4 times along with the total duration of dosage; the carrier state of S. pneumoniae reduced by 3,7 times, H. influenzae — by 3,9 times. In the course of application of three vaccines, the frequency of persistent heat erospecific infectious bronchopulmonary pathology acerbations reduced by 3,3 times. The carrier state of S. pneumoniae reduced by 2,5 times, H. influenzae — by 4,1 times. Thus, vaccine immunization to treat for flu, pneumococcal and HIB disease in various combinations may be recoma mended for wider application to reduce the frequency and severity of heat erospecific infectious respiratory diseases among sickly children, who often suffer from various illnesses.Key words: children with recurrent diseases, vaccination, prevention, flu, H. Influenzae, S. pneumoniae.

  5. Characterization of nontypable Haemophilus influenzae isolates recovered from adult patients with underlying chronic lung disease reveals genotypic and phenotypic traits associated with persistent infection.

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    Junkal Garmendia

    Full Text Available Nontypable Haemophilus influenzae (NTHi has emerged as an important opportunistic pathogen causing infection in adults suffering obstructive lung diseases. Existing evidence associates chronic infection by NTHi to the progression of the chronic respiratory disease, but specific features of NTHi associated with persistence have not been comprehensively addressed. To provide clues about adaptive strategies adopted by NTHi during persistent infection, we compared sequential persistent isolates with newly acquired isolates in sputa from six patients with chronic obstructive lung disease. Pulse field gel electrophoresis (PFGE identified three patients with consecutive persistent strains and three with new strains. Phenotypic characterisation included infection of respiratory epithelial cells, bacterial self-aggregation, biofilm formation and resistance to antimicrobial peptides (AMP. Persistent isolates differed from new strains in showing low epithelial adhesion and inability to form biofilms when grown under continuous-flow culture conditions in microfermenters. Self-aggregation clustered the strains by patient, not by persistence. Increasing resistance to AMPs was observed for each series of persistent isolates; this was not associated with lipooligosaccharide decoration with phosphorylcholine or with lipid A acylation. Variation was further analyzed for the series of three persistent isolates recovered from patient 1. These isolates displayed comparable growth rate, natural transformation frequency and murine pulmonary infection. Genome sequencing of these three isolates revealed sequential acquisition of single-nucleotide variants in the AMP permease sapC, the heme acquisition systems hgpB, hgpC, hup and hxuC, the 3-deoxy-D-manno-octulosonic acid kinase kdkA, the long-chain fatty acid transporter ompP1, and the phosphoribosylamine glycine ligase purD. Collectively, we frame a range of pathogenic traits and a repertoire of genetic variants in the

  6. Prevalence of macrolide-non-susceptible isolates among β-lactamase-negative ampicillin-resistant Haemophilus influenzae in a tertiary care hospital in Japan.

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    Wajima, Takeaki; Seyama, Shoji; Nakamura, Yuka; Kashima, Chihiro; Nakaminami, Hidemasa; Ushio, Masanobu; Fujii, Takeshi; Noguchi, Norihisa

    2016-09-01

    β-Lactamase-negative ampicillin-resistant (BLNAR) Haemophilus influenzae account for a large portion of H. influenzae clinical isolates in Japan. The aim of this study was to clarify the antimicrobial susceptibility of BLNAR H. influenzae clinical isolates as well as the annual changes in susceptibility. BLNAR H. influenzae isolates were collected from a tertiary care hospital from 2007 to 2012. Antimicrobial susceptibility testing was performed and resistance mechanisms were analysed. All of the isolates (n=304) had amino acid substitutions in penicillin-binding protein 3 (PBP3) and isolates were classified by these amino acid substitutions: R517H or N526K (class I); S385T and R517H (class II); and S385T and N526K (class III). Classes I, II and III represented 8.2% (n=25), 9.5% (n=29) and 81.6% (n=248) of the isolates, respectively; 2 isolates could not be classified because they had a PBP3 with a substantially mutated FtsI transpeptidase domain. All of the isolates were highly susceptible to fluoroquinolones and carbapenems. The number of clarithromycin (CAM)-non-susceptible [minimum inhibitory concentration (MIC) ≥16μg/mL] H. influenzae isolates increased significantly between 2010 and 2012. Moreover, CAM-non-susceptible H. influenzae isolates were prevalent among class II and class III BLNAR H. influenzae. Multilocus sequence typing (MLST) of the CAM-resistant (MIC ≥32μg/mL) H. influenzae isolates showed that they were not specific sequence types, suggesting that CAM resistance may occur in any isolates. These results raise concern regarding the occurrence of multidrug-resistant BLNAR H. influenzae. Copyright © 2016 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.

  7. The ecology of nasal colonization of Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus: the role of competition and interactions with host's immune response.

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    Margolis, Elisa; Yates, Andrew; Levin, Bruce R

    2010-02-23

    The first step in invasive disease caused by the normally commensal bacteria Streptococcus pneumoniae, Staphylococcus aureus and Haemophilus influenzae is their colonization of the nasal passages. For any population to colonize a new habitat it is necessary for it to be able to compete with the existing organisms and evade predation. In the case of colonization of these species the competition is between strains of the same and different species of bacteria and the predation is mediated by the host's immune response. Here, we use a neonatal rat model to explore these elements of the ecology of nasal colonization by these occasionally invasive bacteria. When neonatal rats are colonized by any one of these species the density of bacteria in the nasal passage rapidly reaches a steady-state density that is species-specific but independent of inoculum size. When novel populations of H. influenzae and S. pneumoniae are introduced into the nasal passages of neonatal rats with established populations of the same species, residents and invaders coexisted. However, this was not the case for S. aureus - the established population inhibited invasion of new S. aureus populations. In mixed-species introductions, S. aureus or S. pneumoniae facilitated the invasion of another H. influenzae population; for other pairs the interaction was antagonistic and immune-mediated. For example, under some conditions H. influenzae promoted an immune response which limited the invasion of S. pneumoniae. Nasal colonization is a dynamic process with turnover of new strains and new species. These results suggest that multiple strains of either H. influenzae or S. pneumoniae can coexist; in contrast, S. aureus strains require a host to have no other S. aureus present to colonize. Levels of colonization (and hence the possible risk of invasive disease) by H. influenzae are increased in hosts pre-colonized with either S. aureus or S. pneumoniae.

  8. Comparative supragenomic analyses among the pathogens Staphylococcus aureus, Streptococcus pneumoniae, and Haemophilus influenzae using a modification of the finite supragenome model.

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    Boissy, Robert; Ahmed, Azad; Janto, Benjamin; Earl, Josh; Hall, Barry G; Hogg, Justin S; Pusch, Gordon D; Hiller, Luisa N; Powell, Evan; Hayes, Jay; Yu, Susan; Kathju, Sandeep; Stoodley, Paul; Post, J Christopher; Ehrlich, Garth D; Hu, Fen Z

    2011-04-13

    Staphylococcus aureus is associated with a spectrum of symbiotic relationships with its human host from carriage to sepsis and is frequently associated with nosocomial and community-acquired infections, thus the differential gene content among strains is of interest. We sequenced three clinical strains and combined these data with 13 publically available human isolates and one bovine strain for comparative genomic analyses. All genomes were annotated using RAST, and then their gene similarities and differences were delineated. Gene clustering yielded 3,155 orthologous gene clusters, of which 2,266 were core, 755 were distributed, and 134 were unique. Individual genomes contained between 2,524 and 2,648 genes. Gene-content comparisons among all possible S. aureus strain pairs (n = 136) revealed a mean difference of 296 genes and a maximum difference of 476 genes. We developed a revised version of our finite supragenome model to estimate the size of the S. aureus supragenome (3,221 genes, with 2,245 core genes), and compared it with those of Haemophilus influenzae and Streptococcus pneumoniae. There was excellent agreement between RAST's annotations and our CDS clustering procedure providing for high fidelity metabolomic subsystem analyses to extend our comparative genomic characterization of these strains. Using a multi-species comparative supragenomic analysis enabled by an improved version of our finite supragenome model we provide data and an interpretation explaining the relatively larger core genome of S. aureus compared to other opportunistic nasopharyngeal pathogens. In addition, we provide independent validation for the efficiency and effectiveness of our orthologous gene clustering algorithm.

  9. Longitudinal study on Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus nasopharyngeal colonization in HIV-infected and -uninfected infants vaccinated with pneumococcal conjugate vaccine.

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    Madhi, Shabir A; Izu, Alane; Nunes, Marta C; Violari, Avye; Cotton, Mark F; Jean-Philippe, Patrick; Klugman, Keith P; von Gottberg, Anne; van Niekerk, Nadia; Adrian, Peter V

    2015-05-28

    Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus are all potentially pathogenic, which frequently colonize the nasopharynx (NP) prior to causing disease. We studied bacterial NP-colonization in 321 HIV-infected and 243 HIV-uninfected children vaccinated with 7-valent pneumococcal conjugate vaccine (PCV7) at 6, 10 and 14 weeks of age. HIV-uninfected infants included those born to HIV-uninfected (HUU) and HIV-infected women (HEU); HIV-infected children with CD4+ lymphocyte ≥25% were randomized to initiate antiretroviral therapy immediately (ART-Immed) or when clinically indicated (ART-Def). Nasopharyngeal swabs for bacterial culture were taken prior to each PCV7 dose (Visits 1-3) and at 20, 39, 47 and 67 weeks of age (Visits 4-7). Swabs were cultured by standard methods and pneumococcal serotyping done by the Quellung method. Colonization patterns for pneumococcus, H. influenzae and S. aureus did not differ between HUU and HEU children; and were also generally similar between ART-Def and ART-Immed children. Prevalence of PCV7-serotype colonization was similar between HIV-infected and HIV-uninfected children, however, overall pneumococcal and specifically non-vaccine serotype colonization tended to be lower in HIV-infected children. HIV-infected children also had a 44% lower prevalence of S. aureus colonization at Visit-1 (p=0.010); and H. influenzae colonization was also lower among HIV-infected than HIV-uninfected children at Visit-2, Visit-3, Visit-6 and Visit-7. Vaccine-serotype colonization is similar in PCV-immunized HIV-infected and HIV-uninfected children. We, however, identified a lower prevalence of overall-pneumococcal and H. influenzae colonization in HIV-infected children post-PCV vaccination, the clinical-relevance of which warrants further study. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Relationships between rhinitis symptoms, respiratory viral infections and nasopharyngeal colonization with Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus in children attending daycare.

    Science.gov (United States)

    Rodrigues, Fernanda; Foster, Dona; Nicoli, Emily; Trotter, Caroline; Vipond, Barry; Muir, Peter; Gonçalves, Guilherme; Januário, Luís; Finn, Adam

    2013-03-01

    Nasal bacterial colonization is often dubbed "asymptomatic." We hypothesized that rhinitis, common in preschool children, is associated with bacterial colonization and that respiratory viruses, which cause rhinitis, interact with bacteria in ways which promote transmission. Five hundred eighty-five children (4.2-73.6 months) attending daycare had clinical information, a rhinitis score and nasal swabs collected in February 2009. Swabs in soya tryptone glucose glycerine broth were cultured for Streptococcus pneumoniae (Sp), Haemophilus influenzae (Hi) and Staphylococcus aureus and analyzed by real-time polymerase chain reaction for respiratory viruses, both semiquantitatively. Rhinitis symptoms, carriage of Sp and Hi and viral detection fell, whereas S. aureus carriage rates rose with age. Significant, age-independent associations between rhinitis symptoms and detection of Hi (P < 0.033) and Hi colonization density (P < 0.027) were observed. Of the 42% with detected viruses, most (78%) had picornavirus detection. There was a significant age-independent association between viral detection (and viral load, picornavirus detection and picorn aviral load) and detection of Sp (P = 0.020, 0.035, 0.005, 0.014) and between viral detection and viral load and Sp colonization density (P = 0.024, 0.028) [corrected]. Hi may promote its own transmission by inducing or ampli¬fying rhinitis in children. There isa close quantitative relationship between respiratory viral detection, including picornavirus detection and Spcoloni¬zation. These findings have implications for understanding disease patho¬genesis and formulating prevention strategies using vaccines [corrected].

  11. Interrelationship of Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus colonization within and between pneumococcal-vaccine naïve mother-child dyads.

    Science.gov (United States)

    Shiri, Tinevimbo; Nunes, Marta C; Adrian, Peter V; Van Niekerk, Nadia; Klugman, Keith P; Madhi, Shabir A

    2013-10-17

    A high prevalence of bacterial nasopharyngeal co-infections has been reported in children, however, such data is limited in adults. We examined the interaction of Haemophilus influenzae, Staphylococcus aureus and Streptococcus pneumoniae pharyngeal colonization in mother-child dyads. Pneumococcal-vaccine naïve children and their mothers had pharyngeal swabs undertaken at 1.6, 2.5, 3.5, 4.5, 7.4, 9.5, 12.5, 16.2 and 24.2 months of child's age. Swabs were cultured for S. pneumoniae, H. influenzae and S. aureus using standard microbiologic methods. Multivariate generalized estimating equation-models were used to explore the associations of the three bacteria within and between children and their mothers. In children, the observed probability of co-colonization was higher than expected. Well-defined associations in colonization between the bacteria were observed in children but not among mothers. In children, a synergistic association was observed between S. pneumoniae and H. influenzae (Adjusted odds ratio (AOR): 1.75, 95% CI: 1.32-2.32) and a negative association between S. pneumoniae and S. aureus (AOR: 0.51, 95% CI: 0.39-0.67) or H. influenzae and S. aureus (AOR: 0.24, 95% CI: 0.16-0.34) colonization. Additionally, all three bacteria had a higher likelihood of concurrent colonization. There was a strong association in colonization by the bacteria in children and their mothers, including increased likelihood of maternal colonization if the child was colonized by S. pneumoniae (AOR: 1.84, 95% CI: 1.28-2.63) and H. influenzae (AOR: 6.34, 95% CI: 2.24-18.0). The effects of immunization of children with pneumococcal-conjugate-vaccine in settings such as ours needs monitoring with regard to potential changes of pharyngeal bacterial ecology which could occur in vaccinated and -unvaccinated age-groups.

  12. Nontypeable Haemophilus Influenzae Infection Upregulates the NLRP3 Inflammasome and Leads to Caspase-1-Dependent Secretion of Interleukin-1β - A Possible Pathway of Exacerbations in COPD.

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    Johannes Rotta Detto Loria

    Full Text Available Nontypeable Haemophilus influenzae (NTHi is the most common cause for bacterial exacerbations in chronic obstructive pulmonary disease (COPD. Recent investigations suggest the participation of the inflammasome in the pathomechanism of airway inflammation. The inflammasome is a cytosolic protein complex important for early inflammatory responses, by processing Interleukin-1β (IL-1β to its active form.Since inflammasome activation has been described for a variety of inflammatory diseases, we investigated whether this pathway plays a role in NTHi infection of the airways.A murine macrophage cell line (RAW 264.7, human alveolar macrophages and human lung tissue (HLT were stimulated with viable or non-viable NTHi and/or nigericin, a potassium ionophore. Secreted cytokines were measured with ELISA and participating proteins detected via Western Blot or immunohistochemistry.Western Blot analysis of cells and immunohistochemistry of lung tissue detected the inflammasome key components NLRP3 and caspase-1 after stimulation, leading to a significant induction of IL-1β expression (RAW: control at the lower detection limit vs. NTHi 505±111pg/ml, p<0.01. Inhibition of caspase-1 in human lung tissue led to a significant reduction of IL-1β and IL-18 levels (IL-1β: NTHi 24 h 17423±3198pg/ml vs. NTHi+Z-YVAD-FMK 6961±1751pg/ml, p<0.01.Our data demonstrate the upregulation of the NRLP3-inflammasome during NTHi-induced inflammation in respiratory cells and tissues. Our findings concerning caspase-1 dependent IL-1β release suggest a role for the inflammasome in respiratory tract infections with NTHi which may be relevant for the pathogenesis of bacterial exacerbations in COPD.

  13. DNA-binding by Haemophilus influenzae and Escherichia coli YbaB, members of a widely-distributed bacterial protein family

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    Miller M Clarke

    2009-07-01

    Full Text Available Abstract Background Genes orthologous to the ybaB loci of Escherichia coli and Haemophilus influenzae are widely distributed among eubacteria. Several years ago, the three-dimensional structures of the YbaB orthologs of both E. coli and H. influenzae were determined, revealing a novel "tweezer"-like structure. However, a function for YbaB had remained elusive, with an early study of the H. influenzae ortholog failing to detect DNA-binding activity. Our group recently determined that the Borrelia burgdorferi YbaB ortholog, EbfC, is a DNA-binding protein. To reconcile those results, we assessed the abilities of both the H. influenzae and E. coli YbaB proteins to bind DNA to which B. burgdorferi EbfC can bind. Results Both the H. influenzae and the E. coli YbaB proteins bound to tested DNAs. DNA-binding was not well competed with poly-dI-dC, indicating some sequence preferences for those two proteins. Analyses of binding characteristics determined that both YbaB orthologs bind as homodimers. Different DNA sequence preferences were observed between H. influenzae YbaB, E. coli YbaB and B. burgdorferi EbfC, consistent with amino acid differences in the putative DNA-binding domains of these proteins. Conclusion Three distinct members of the YbaB/EbfC bacterial protein family have now been demonstrated to bind DNA. Members of this protein family are encoded by a broad range of bacteria, including many pathogenic species, and results of our studies suggest that all such proteins have DNA-binding activities. The functions of YbaB/EbfC family members in each bacterial species are as-yet unknown, but given the ubiquity of these DNA-binding proteins among Eubacteria, further investigations are warranted.

  14. Diminished ICAM-1 expression and impaired pulmonary clearance of nontypeable Haemophilus influenzae in a mouse model of chronic obstructive pulmonary disease/emphysema.

    Science.gov (United States)

    Pang, Bing; Hong, Wenzhou; West-Barnette, Shayla L; Kock, Nancy D; Swords, W Edward

    2008-11-01

    The airways of patients with chronic obstructive pulmonary disease (COPD) are continually colonized with bacterial opportunists like nontypeable Haemophilus influenzae (NTHi), and a wealth of evidence indicates that changes in bacterial populations within the lung can influence the severity of COPD. In this study, we used a murine model for COPD/emphysema to test the hypothesis that COPD affects pulmonary clearance. Mice were treated with a pulmonary bolus of elastase, and as reported previously, the lungs of these mice were pathologically similar to those with COPD/emphysema at approximately 1 month posttreatment. Pulmonary clearance of NTHi was significantly impaired in elastase-treated versus mock-treated mice. While histopathologic analysis revealed minimal differences in localized lung inflammation between the two groups, lower levels of intercellular adhesion molecule 1 (ICAM-1) were observed for the airway epithelial surface of elastase-treated mice than for those of control mice. Following infection, elastase-treated mice had lung pathology consistent with pneumonia for as long as 72 h postinfection, whereas at the same time point, mock-treated mice had cleared NTHi and showed little apparent pathology. Large aggregates of bacteria were observed within damaged lung tissue of the elastase-treated mice, whereas sparse individual bacteria were observed in lungs of mock-treated mice at the same time point postinfection. Additional infection studies showed that NTHi mutants with biofilm defects were less persistent in the elastase-treated mice than the parent strain. These findings establish a model for COPD-related infections and support the hypotheses that ICAM-1 promotes clearance of NTHi. Furthermore, the data indicate that NTHi may form biofilms within the context of COPD-related infections.

  15. Haemophilus influenzae : Caracterización de aislamientos recuperados de enfermedades invasivas en Cuba durante el período 2008-2011

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    Gilda Toraño

    2012-12-01

    Full Text Available Con el objetivo de caracterizar los aislamientos de Haemophilus influenzae, responsables de enfermedades invasivas en Cuba, en la etapa posterior a la vacunación se estudió el total de los recuperados durante el período 2008-2011, remitidos al Instituto "Pedro Kourí" desde diferentes provincias del país. La confirmación de especie y determinación de serotipos se realizó atendiendo al requerimiento de los factores V y X y empleando el método de aglutinación en lámina, respectivamente. Se definieron los biotipos a través de las pruebas de indol, urea y ornitina; se determinó la concentración mínima inhibitoria (CMI mediante la prueba del elipsómetro para la ampicilina, la ceftriaxona, el cloranfenicol y la rifampicina. Para 23 aislamientos se corroboró la identificación como H. influenzae : 21 fueron serotipables y 2 no tipables (HNT. El 90,4% de los serotipables fueron serotipo b y se detectaron dos serotipos a. Nueve aislamientos de H. influenzae b pertenecieron al biotipo I y los aislamientos, serotipo a y HNT, al biotipo II. En una cepa se demostró producción de la enzima ß-lactamasa y resistencia para la ampicilina y el cloranfenicol, con valores de CMI= 8 y 12 µg/mL, respectivamente. Se puso en evidencia que a pesar de la disminución de la incidencia de la enfermedad invasiva por Hib, este serotipo aún constituye el más frecuente y se alerta sobre la necesidad de una vigilancia sostenida que permita detectar fallos vacunales. La susceptibilidad antimicrobiana demostrada para este período pudiera considerarse como un beneficio adicional de la introducción de la vacunación en Cuba.

  16. Colonization of healthy children by Moraxella catarrhalis is characterized by genotype heterogeneity, virulence gene diversity and co-colonization with Haemophilus influenzae.

    Science.gov (United States)

    Verhaegh, Suzanne J C; Snippe, Martine L; Levy, Foster; Verbrugh, Henri A; Jaddoe, Vincent W V; Hofman, Albert; Moll, Henriëtte A; van Belkum, Alex; Hays, John P

    2011-01-01

    The colonization dynamics of Moraxella catarrhalis were studied in a population comprising 1079 healthy children living in Rotterdam, The Netherlands (the Generation R Focus cohort). A total of 2751 nasal swabs were obtained during four clinic visits timed to take place at 1.5, 6, 14 and 24 months of age, yielding a total of 709 M. catarrhalis and 621 Haemophilus influenzae isolates. Between January 2004 and December 2006, approximate but regular 6-monthly cycles of colonization were observed, with peak colonization incidences occurring in the autumn/winter for M. catarrhalis, and winter/spring for H. influenzae. Co-colonization was significantly more likely than single-species colonization with either M. catarrhalis or H. influenzae, with genotypic analysis revealing no clonality for co-colonizing or single colonizers of either bacterial species. This finding is especially relevant considering the recent discovery of the importance of H. influenzae-M. catarrhalis quorum sensing in biofilm formation and host clearance. Bacterial genotype heterogeneity was maintained over the 3-year period of the study, even within this relatively localized geographical region, and there was no association of genotypes with either season or year of isolation. Furthermore, chronological and genotypic diversity in three immunologically important M. catarrhalis virulence genes (uspA1, uspA2 and hag/mid) was also observed. This study indicates that genotypic variation is a key factor contributing to the success of M. catarrhalis colonization of healthy children in the first years of life. Furthermore, variation in immunologically relevant virulence genes within colonizing populations, and even within genotypically identical M. catarrhalis isolates, may be a result of immune evasion by this pathogen. Finally, the factors facilitating M. catarrhalis and H. influenzae co-colonization need to be further investigated.

  17. Factors affecting the introduction of new vaccines to poor nations: a comparative study of the Haemophilus influenzae type B and hepatitis B vaccines.

    Directory of Open Access Journals (Sweden)

    Aharona Glatman-Freedman

    Full Text Available BACKGROUND: A major effort to introduce new vaccines into poor nations of the world was initiated in recent years with the help of the GAVI alliance. The first vaccines introduced have been the Haemophilus influenzae type B (Hib and the hepatitis B (Hep B vaccines. The introduction of these vaccines during the first phase of GAVI's operations demonstrated considerable variability. We set out to study the factors affecting the introduction of these vaccines. The African Region (AFRO, where new vaccines were introduced to a substantial number of countries during the first phase of GAVI's funding, was selected for this study. METHODOLOGY/PRINCIPAL FINDINGS: GAVI-eligible AFRO countries with a population of 0.5 million or more were included in the study. Countries were analyzed and compared for new vaccine introduction, healthcare indicators, financial indicators related to healthcare and country-level Governance Indicators, using One Way ANOVA, correlation analysis and Qualitative Comparative Analysis (QCA. Introduction of new vaccines into AFRO nations was associated primarily with high country-level Governance Indicator scores. The use of individual Governance Indicator scores, as well as a combined Governance Indicator score we developed, demonstrated similar results. CONCLUSIONS/SIGNIFICANCE: Our study results indicate that good country-level governance is an imperative pre-requisite for the successful early introduction of new vaccines into poor African nations. Enhanced support measures may be required to effectively introduce new vaccines to countries with low governance scores. The combined governance score we developed may thus constitute a useful tool for helping philanthropic organizations make decisions regarding the type of support needed by different countries to achieve success.

  18. Factors Affecting the Introduction of New Vaccines to Poor Nations: A Comparative Study of the Haemophilus influenzae Type B and Hepatitis B Vaccines

    Science.gov (United States)

    Glatman-Freedman, Aharona; Cohen, Mary-Louise; Nichols, Katherine A.; Porges, Robert F.; Saludes, Ivy Rayos; Steffens, Kevin; Rodwin, Victor G.; Britt, David W.

    2010-01-01

    Background A major effort to introduce new vaccines into poor nations of the world was initiated in recent years with the help of the GAVI alliance. The first vaccines introduced have been the Haemophilus influenzae type B (Hib) and the hepatitis B (Hep B) vaccines. The introduction of these vaccines during the first phase of GAVI's operations demonstrated considerable variability. We set out to study the factors affecting the introduction of these vaccines. The African Region (AFRO), where new vaccines were introduced to a substantial number of countries during the first phase of GAVI's funding, was selected for this study. Methodology/Principal Findings GAVI-eligible AFRO countries with a population of 0.5 million or more were included in the study. Countries were analyzed and compared for new vaccine introduction, healthcare indicators, financial indicators related to healthcare and country-level Governance Indicators, using One Way ANOVA, correlation analysis and Qualitative Comparative Analysis (QCA). Introduction of new vaccines into AFRO nations was associated primarily with high country-level Governance Indicator scores. The use of individual Governance Indicator scores, as well as a combined Governance Indicator score we developed, demonstrated similar results. Conclusions/Significance Our study results indicate that good country-level governance is an imperative pre-requisite for the successful early introduction of new vaccines into poor African nations. Enhanced support measures may be required to effectively introduce new vaccines to countries with low governance scores. The combined governance score we developed may thus constitute a useful tool for helping philanthropic organizations make decisions regarding the type of support needed by different countries to achieve success. PMID:21072192

  19. Virtual reality exposure therapy

    OpenAIRE

    Rothbaum, BO; Hodges, L; Kooper, R

    1997-01-01

    It has been proposed that virtual reality (VR) exposure may be an alternative to standard in vivo exposure. Virtual reality integrates real-time computer graphics, body tracking devices, visual displays, and other sensory input devices to immerse a participant in a computer- generated virtual environment. Virtual reality exposure is potentially an efficient and cost-effective treatment of anxiety disorders. VR exposure therapy reduced the fear of heights in the first control...

  20. Assessment of human exposures

    Energy Technology Data Exchange (ETDEWEB)

    Lebret, E. [RIVM-National Inst. of Public Health and Environmental Protection (Netherlands)

    1995-12-31

    This article describes some of the features of the assessment of human exposure to environmental pollutants in epidemiological studies. Since exposure assessment in air pollution epidemiology studies typically involve professionals from various backgrounds, interpretation of a concepts like `exposure` may vary. A brief descriptions is therefore given by way of introduction

  1. Opioid Antagonist Impedes Exposure.

    Science.gov (United States)

    Merluzzi, Thomas V.; And Others

    1991-01-01

    Thirty spider-phobic adults underwent exposure to 17 phobic-related, graded performance tests. Fifteen subjects were assigned to naltrexone, an opioid antagonist, and 15 were assigned to placebo. Naltrexone had a significant effect on exposure, with naltrexone subjects taking significantly longer to complete first 10 steps of exposure and with…

  2. OCCUPATIONAL EXPOSURE AND COPD

    DEFF Research Database (Denmark)

    Würtz, Else Toft

    Chronic Obstructive Pulmonary Disease (COPD) is a common disease. The main risk factor is smoking although 15% of the COPD cases are expected to be preventable if the occupational exposures from vapour, gas, dust, and fume were eliminated; the population attributable fraction (PAF). The thesis...... addresses the association between occupational exposure and COPD in a population-based cohort of Danes aged 45-84-years. 4717 participants were included at baseline and 2624 at the four year follow-up. COPD was defined by spirometry and the occupational exposure was based on specialist defined jobs...... and questionnaires. The main occupational exposure was organic dust and 49% reported no lifetime occupational exposure. The results suggest occupational exposures to be associated to COPD also in never smokers and women. We found an exposure-response relation in the cross sectional analyses. The results...

  3. Coprecipitation of lipopolysaccharide and the 39,000-molecular-weight major outer membrane protein of Haemophilus influenzae type b by lipopolysaccharide-directed monoclonal antibody.

    Science.gov (United States)

    Gulig, P A; Hansen, E J

    1985-01-01

    The major outer membrane protein of Haemophilus influenzae type b (Hib) with an apparent molecular weight of 39,000 (39K) was purified from three different Hib strains and was shown to be free from detectable contamination with other proteins. However, these purified 39K protein preparations were found to contain Hib lipopolysaccharide (LPS). Immunization of rats with these 39K protein preparations resulted in the production of antisera containing both 39K protein-directed and LPS-directed antibodies, as determined by Western blot analysis. The reactivity pattern of the LPS-directed serum antibodies with different Hib strains was identical to the reactivity of these Hib strains with a set of monoclonal antibodies (mabs) previously shown to immunoprecipitate the 39K protein in a radioimmunoprecipitation (RIP) system. Examination of the antigenic specificities of the 39K protein-immunoprecipitating mabs by using Western blot analysis showed that these mabs were actually directed against Hib LPS. RIP analysis of 125I-labeled Hib cells and 32P-labeled Hib cells revealed that the 39K protein and LPS existed as a complex in a RIP system, which resulted in the coprecipitation of both antigens by LPS-directed mabs. The interaction between LPS and the 39K protein was highly selective for this protein and did not involve other outer membrane proteins. The LPS/39K protein complex could be reconstituted by mixing purified LPS and purified 39K protein; it could also be reconstituted with 39K protein from one Hib strain and LPS from another Hib strain. These findings have necessitated the reinterpretation of previous studies involving the 39K protein-immunoprecipitating mabs. Of primary importance is the fact that the demonstrated immunoprotective ability of a 39K protein-immunoprecipitating mab (E. J. Hansen, S. M. Robertson, P. A. Gulig, C. F. Frisch, and E. J. Haanes, Lancet i:366-368, 1982) must now be regarded as evidence that antibody directed against Hib LPS can be

  4. The iron/heme regulated genes of Haemophilus influenzae: comparative transcriptional profiling as a tool to define the species core modulon

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    Morton Daniel J

    2009-01-01

    Full Text Available Abstract Background Haemophilus influenzae requires heme for aerobic growth and possesses multiple mechanisms to obtain this essential nutrient. Although an understanding of the heme acquisition mechanisms of H. influenzae is emerging, significant gaps in our knowledge remain. Unresolved issues include the identities of all genes exhibiting altered transcription in response to iron and heme availability, the fraction of such genes functioning in iron/heme acquisition, and the heterogeneity of this gene set among clinical isolates. Previously we utilized H. influenzae strain Rd KW20 to demonstrate the utility of transcriptional profiling in defining the genes exhibiting altered transcription in response to environmental iron and heme levels. The current study expands upon those observations by determining the iron/heme modulons of two clinical isolates, the type b isolate 10810 and the nontypeable isolate R2866. These data are used to begin to define the core iron/heme modulon of the species. Results Microarray studies were performed to compare gene expression on transition from iron/heme-restricted to iron/heme-replete conditions for each isolate. Of 1820 ORFs on the array corresponding to R2866 genes, 363 were significantly differentially expressed: 233 were maximally transcribed under iron/heme-replete conditions and 130 under iron/heme-restricted conditions. Of the 1883 ORFs representing genes of strain 10810, 353 were significantly differentially transcribed: 150 were preferentially transcribed under iron/heme-replete conditions and 203 under iron/heme-restricted conditions. Comparison of the data sets indicated that 163 genes exhibited similar regulation in both isolates and that 74 of these exhibited similar patterns of regulation in Rd KW20. These comprise the putative core iron/heme modulon. Conclusion This study provides evidence for a conserved core of H. influenzae genes the transcription of which is altered by the availability of

  5. Development and characterization of a pooled Haemophilus influenzae genomic library for the evaluation of gene expression changes associated with mucosal biofilm formation in otitis media.

    Science.gov (United States)

    Erdos, Geza; Sayeed, Sameera; Antalis, Patricia; Hu, Fen Ze; Hayes, Jay; Goodwin, Joseph; Dopico, Richard; Post, J Christopher; Ehrlich, Garth D

    2003-07-01

    Haemophilus influenzae is one of the most important respiratory pathogens of man. It has been etiologically associated with otitis media, otorrhea, and chronic obstructive pulmonary disease. Identification of new genomic elements will provide novel targets to fight chronic infections caused by this organism. The new paradigm that chronic infections are caused by bacterial biofilms prompted us to study the relationship between bacterial pathogenicity, biofilm formation and bacterial communal cooperation. To do this, it is essential to determine the virulence gene sets that are involved in the above processes and whether they are present in every bacterial cell or distributed in a "communal gene-pool", the distributed genome hypothesis (DGH). We designed, constructed and characterized a highly redundant genomic DNA library comprised of the genomes of ten low passage clinical isolates of H. influenzae carrying large numbers of genes that are not present in the laboratory strains of H. influenzae. Genomic DNA fragments of the ten clinical strains were hydro-dynamically sheared to produce a mean fragment size of 1.5-2.5 kb. The ten sheared DNAs were than pooled and used in the construction of a genomic library with 76800 clones. Our restriction endonuclease and sequence analyses of 800 clones demonstrate that 75% of the clones carry an insert larger than 0.5 kb. The library has an approximately 1.5 kb average insert size, and therefore, better than 4.5x redundancy for each of the genomes of the ten clinical isolates. Our sequencing effort ( approximately 1 million nucleotides to date) reveals that a high percentage of genes (75 clones, 11% of the 686 sequenced clones) present in this library are not represented in the genome of the reference strain H. influenzae Rd. The library, based on the above results, has a better than 4.5x coverage for each of the ten constituent genomes. On the basis of our preliminary sequencing data ( approximately 1 million nucleotides) the

  6. Defining the binding region in factor H to develop a therapeutic factor H-Fc fusion protein against nontypeable Haemophilus influenzae

    Directory of Open Access Journals (Sweden)

    Sandy M. Wong

    2016-04-01

    Full Text Available Nontypeable Haemophilus influenzae (NTHi cause a range of illnesses including otitis media, sinusitis, and exacerbation of chronic obstructive pulmonary disease, infections that contribute to the problem of antibiotic resistance and are themselves often intractable to standard antibiotic treatment regimens. We investigated a strategy to exploit binding of the complement inhibitor Factor H (FH to NTHi as a functional target for an immunotherapeutic containing the NTHi binding domain of FH fused to the Fc domain of IgG1. Chimeric proteins containing the regions that most FH-binding bacteria use to engage human FH, domains 6 and 7 (FH6,7/Fc and/or 18 through 20 (FH18-20/Fc, were evaluated for binding to NTHi. FH6,7/Fc bound strongly to each of seven NTHi clinical isolates tested and efficiently promoted complement-mediated killing by normal human serum. FH18-20/Fc bound weakly to three of the strains but did not promote complement dependent killing. Outer-membrane protein P5 has been implicated in FH binding by NTHi, and FH6,7/Fc binding was greatly diminished in five of seven P5 deficient isogenic mutant strains tested, implicating an alternative FH binding protein in some strains. Binding of FH18-20/Fc was decreased in the P5 mutant of one strain. A murine model was used to evaluate potential therapeutic application of FH6,7/Fc. FH6,7/Fc efficiently promoted binding of C3 to NTHi exposed to mouse serum, and intranasal delivery of FH6,7/Fc resulted in significantly enhanced clearance of NTHi from the lung. Moreover, a P5 deficient mutant was attenuated for survival in the lung model, suggesting that escape mutants lacking P5 would be less likely to replace strains susceptible to FH6,7/Fc. These results provide evidence for the potential utility of FH6,7/Fc as a therapeutic against NTHi lung infection. FH binding is a common property of many respiratory tract pathogens and FH/Fc chimeras may represent promising alternative or adjunctive

  7. Vigilancia epidemiológica centinela de Haemophilus influenzae y Streptococcus pneumoniae en menores de 5 años en el Perú

    Directory of Open Access Journals (Sweden)

    2003-07-01

    Full Text Available Objetivo: Determinar la frecuencia, serotipos y perfil de resistencia antimicrobiana de Haemophilus influenzae (Hi y Streptococcus pneumoniae (Spn en casos de neumonía y meningitis en niños menores de 5 años en el Perú. Materiales y métodos: Entre octubre de 2000 y diciembre de 2001, se implementó la vigilancia centinela de Hi y Spn en dos hospitales de Lima y tres hospitales de otros departamentos (Cusco, Arequipa y Puno. La identificación de serotipos y el estudio de la resistencia antimicrobiana se realizaron en el Instituto Nacional de Salud de Lima, Perú. La susceptibilidad antimicrobiana por la concentración inhibitoria mínima (CIM se realizó por el método de microdilución en placa, siguiendo las pautas del Comité Nacional de Estándares de Laboratorios Clínicos (NCCLS. Resultados: Ingresaron 1 283 casos. Se aislaron 59 cepas (31 de Hi y 28 de Spn, de ellos, 2,3% de las neumonías y 42,5% de las meningitis tuvieron aislamiento bacteriológico. En 10/1210 (0,8% pacientes con neumonía se aisló Hi y Spn en 18/1210 (1,5%. En 21/73 (28,8% de los casos de meningitis se aislaron Hi y Spn en 10/73 (13,7%. Se identificaron los serotipos de Spn: 1, 5, 6A, 11, 14, 19, 19F y 20. Los cepas aislados de Hi fueron del serotipo B. Se identificaron cepas de Spn con resistencia alta a penicilina (3/13, cotrimoxazol (3/13, eritromicina (1/13, cloranfenicol (1/13 y ceftriaxona (1/13; y cepas de Hi altamente resistentes a cotrimoxazol (4/20 y ampicilina (1/20. Conclusiones: Las tasas de aislamiento de Spn y Hi en menores de 5 años fueron bastante bajas. Se hallaron serotipos ya encontrados en Latinoamérica, y se identificaron algunas cepas de Spn y Hi con resistencia a los antibióticos utilizados en los esquemas de tratamiento para neumonía y meningitis. Recomendamos continuar con este sistema de vigilancia, basado en hospitales centinela.

  8. Immunogenicity and safety of two doses of catch-up immunization with Haemophilus influenzae type b conjugate vaccine in Indian children living with HIV.

    Science.gov (United States)

    Arya, Bikas K; Bhattacharya, Sangeeta Das; Sutcliffe, Catherine G; Saha, Malay K; Bhattacharyya, Subhasish; Niyogi, Swapan Kumar; Moss, William J; Panda, Samiran; Das, Ranjan Saurav; Mallick, Mausom; Mandal, Sutapa

    2016-04-27

    Children living with HIV are at increased risk of disease from Haemophilus influenzae type b (Hib). Data are limited on the immunogenicity of a two-dose, catch-up schedule for Hib conjugate vaccine (HibCV) among HIV-infected children accessing antiretroviral therapy (ART) late. The objectives of the study were to: (1) evaluate baseline immunity to Hib and the immunogenicity and safety of two doses of HibCV among HIV-infected Indian children; and (2) document the threshold antibody level required to prevent Hib colonization among HIV-infected children following immunization. We conducted a prospective cohort study among HIV-infected children 2-15 years of age and HIV-uninfected children 2-5 years of age. HIV-infected children received two doses of HibCV and uninfected children received one. Serum anti-Hib PRP IgG antibodies were measured at baseline and two months after immunization in the HIV-infected children. Nasopharyngeal (NP) swabs were collected at baseline and follow-up. 125 HIV-infected and 44 uninfected children participated. 40% of HIV-infected children were receiving ART and 26% had a viral load >100,000 copies/mL. The geometric mean concentration of serum anti-Hib PRP antibody increased from 0.25 μg/mL at baseline to 2.65 μg/mL after two doses of HibCV, representing a 10.6-fold increase (pchildren mounted an immune response. Moderate or severe immune suppression, trimethoprim/sulfamethoxazole prophylaxis, and lower baseline antibody levels were associated with lower post-vaccine serum anti-Hib PRP IgG antibodies. A serum anti-Hib PRP IgG antibody level ≥ 3.3 μg/mL was protective against Hib NP colonization. There were no differences in adverse events between HIV-infected and uninfected children. Including a catch-up immunization schedule for older HIV infected children in countries introducing Hib vaccines is important. Older HIV-infected children with delayed access to ART and without suppressed viral loads mounted an adequate immune response

  9. Haemophilus influenzae type-b and non-b-type invasive diseases in urban children (<5years) of Bangladesh: implications for therapy and vaccination.

    Science.gov (United States)

    Rahman, Mahbubur; Hossain, Shahadat; Baqui, Abdullah Hel; Shoma, Shereen; Rashid, Harunur; Nahar, Nazmun; Zaman, Mohammed Khalequ; Khatun, Farida

    2008-03-01

    To prospectively study the epidemiology and antibiotic resistance of Haemophilus infuenzae isolates from invasive infections in children. Children (stain, culture and biochemical tests). Hib antigen was detected by latex agglutination (LA) in culture-negative pyogenic CSF and PCR was done for bexA gene in culture- and LA-negative pyogenic CSF. Antibiotic susceptibility was determined by E-Tests and beta-lactamase by nitrocefin stick. Seventy-three cases of H. influenzae infections (46 of 293 meningitis cases, 25 of 1493 pneumonia cases, 2 of 48 septicemia cases) were detected; 63%, 34% and 3% of them had meningitis, pneumonia and septicemia respectively. H. influenzae type b (Hib) caused infections in 80.8% of cases (60.3% meningitis, 20.5% pneumonia). Most (86%) infections clustered in 4-12month infants. The case-fatality in pneumonia was 8% compared to 19% in meningitis. H. influenzae isolates from pneumonia and meningitis children were equally resistant to antibiotics (46% vs 43%). Of 10 drugs tested, isolates were resistant to ampicillin (31%), chloramphenicol (42%), trimethoprim-sulfamethoxazole (44%) and azithromycin (1.4%). Multidrug-resistant (MDR) strains were equally prevalent in Hib (31%) and non-b-type (29%) isolates, and in pneumonia (31%) and meningitis (34%) cases. None was resistant to amoxicillin-clavulanate, ceftriaxone, ciprofloxacin, levofloxacin, moxifloxacin, and gatifloxacin. Of all H. influenzae infections, 40%, 4.4% and 100% of pneumonia, meningitis and septicemia cases were caused by other serotypes or non-typeable strains. All ampicillin-resistant-strains produced beta-lactamase without detection of beta-lactamase-negative-ampicillin-resistant (BLNAR) strains. Hib is a leading cause of invasive bacterial infections in infants. Multidrug-resistant H. influenzae is common and requires amoxicillin-clavulanate, ceftriaxone or azithromycin as empirical therapy with specific recommendation for use of ceftriaxone for treatment of meningitis

  10. The dapE-encoded N-succinyl-L,L-diaminopimelic acid desuccinylase from Haemophilus influenzae contains two active-site histidine residues.

    Science.gov (United States)

    Gillner, Danuta M; Bienvenue, David L; Nocek, Boguslaw P; Joachimiak, Andrzej; Zachary, Vincentos; Bennett, Brian; Holz, Richard C

    2009-01-01

    The catalytic and structural properties of the H67A and H349A dapE-encoded N-succinyl-L,L-diaminopimelic acid desuccinylase (DapE) from Haemophilus influenzae were investigated. On the basis of sequence alignment with the carboxypeptidase from Pseudomonas sp. strain RS-16, both H67 and H349 were predicted to be Zn(II) ligands. The H67A DapE enzyme exhibited a decreased catalytic efficiency (180-fold) compared with wild-type (WT) DapE towards N-succinyldiaminopimelic acid. No catalytic activity was observed for H349A under the experimental conditions used. The electronic paramagnetic resonance (EPR) and electronic absorption data indicate that the Co(II) ion bound to H349A-DapE is analogous to that of WT DapE after the addition of a single Co(II) ion. The addition of 1 equiv of Co(II) to H67A DapE provides spectra that are very different from those of the first Co(II) binding site of the WT enzyme, but that are similar to those of the second binding site. The EPR and electronic absorption data, in conjunction with the kinetic data, are consistent with the assignment of H67 and H349 as active-site metal ligands for the DapE from H. influenzae. Furthermore, the data suggest that H67 is a ligand in the first metal binding site, while H349 resides in the second metal binding site. A three-dimensional homology structure of the DapE from H. influenzae was generated using the X-ray crystal structure of the DapE from Neisseria meningitidis as a template and superimposed on the structure of the aminopeptidase from Aeromonas proteolytica (AAP). This homology structure confirms the assignment of H67 and H349 as active-site ligands. The superimposition of the homology model of DapE with the dizinc(II) structure of AAP indicates that within 4.0 A of the Zn(II) binding sites of AAP all of the amino acid residues of DapE are nearly identical.

  11. Multiplex quantitative PCR for detection of lower respiratory tract infection and meningitis caused by Streptococcus pneumoniae, Haemophilus influenzae and Neisseria meningitidis

    Directory of Open Access Journals (Sweden)

    Welinder-Olsson Christina

    2010-12-01

    Full Text Available Abstract Background Streptococcus pneumoniae and Haemophilus influenzae cause pneumonia and as Neisseria meningitidis they are important agents of meningitis. Although several PCR methods have been described for these bacteria the specificity is an underestimated problem. Here we present a quantitative multiplex real-time PCR (qmPCR for detection of S. pneumoniae (9802 gene fragment, H. influenzae (omp P6 gene and N. meningitidis (ctrA gene. The method was evaluated on bronchoalveolar lavage (BAL samples from 156 adults with lower respiratory tract infection (LRTI and 31 controls, and on 87 cerebrospinal fluid (CSF samples from meningitis patients. Results The analytical sensitivity was not affected by using a combined mixture of reagents and a combined DNA standard (S. pneumoniae/H. influenzae/N. meningitidis in single tubes. By blood- and BAL-culture and S. pneumoniae urinary antigen test, S. pneumoniae and H. influenzae were aetiological agents in 21 and 31 of the LTRI patients, respectively. These pathogens were identified by qmPCR in 52 and 72 of the cases, respectively, yielding sensitivities and specificities of 95% and 75% for S. pneumoniae, and 90% and 65% for H. influenzae, respectively. When using a cut-off of 105 genome copies/mL for clinical positivity the sensitivities and specificities were 90% and 80% for S. pneumoniae, and 81% and 85% for H. influenzae, respectively. Of 44 culture negative but qmPCR positive for H. influenzae, 41 were confirmed by fucK PCR as H. influenzae. Of the 103 patients who had taken antibiotics prior to sampling, S. pneumoniae and H. influenzae were identified by culture in 6% and 20% of the cases, respectively, and by the qmPCR in 36% and 53% of the cases, respectively. In 87 CSF samples S. pneumoniae and N. meningitidis were identified by culture and/or 16 S rRNA in 14 and 10 samples and by qmPCR in 14 and 10 samples, respectively, giving a sensitivity of 100% and a specificity of 100% for both

  12. Multiplex quantitative PCR for detection of lower respiratory tract infection and meningitis caused by Streptococcus pneumoniae, Haemophilus influenzae and Neisseria meningitidis.

    Science.gov (United States)

    Abdeldaim, Guma M K; Strålin, Kristoffer; Korsgaard, Jens; Blomberg, Jonas; Welinder-Olsson, Christina; Herrmann, Björn

    2010-12-03

    Streptococcus pneumoniae and Haemophilus influenzae cause pneumonia and as Neisseria meningitidis they are important agents of meningitis. Although several PCR methods have been described for these bacteria the specificity is an underestimated problem. Here we present a quantitative multiplex real-time PCR (qmPCR) for detection of S. pneumoniae (9802 gene fragment), H. influenzae (omp P6 gene) and N. meningitidis (ctrA gene). The method was evaluated on bronchoalveolar lavage (BAL) samples from 156 adults with lower respiratory tract infection (LRTI) and 31 controls, and on 87 cerebrospinal fluid (CSF) samples from meningitis patients. The analytical sensitivity was not affected by using a combined mixture of reagents and a combined DNA standard (S. pneumoniae/H. influenzae/N. meningitidis) in single tubes. By blood- and BAL-culture and S. pneumoniae urinary antigen test, S. pneumoniae and H. influenzae were aetiological agents in 21 and 31 of the LTRI patients, respectively. These pathogens were identified by qmPCR in 52 and 72 of the cases, respectively, yielding sensitivities and specificities of 95% and 75% for S. pneumoniae, and 90% and 65% for H. influenzae, respectively. When using a cut-off of 10⁵ genome copies/mL for clinical positivity the sensitivities and specificities were 90% and 80% for S. pneumoniae, and 81% and 85% for H. influenzae, respectively. Of 44 culture negative but qmPCR positive for H. influenzae, 41 were confirmed by fucK PCR as H. influenzae. Of the 103 patients who had taken antibiotics prior to sampling, S. pneumoniae and H. influenzae were identified by culture in 6% and 20% of the cases, respectively, and by the qmPCR in 36% and 53% of the cases, respectively.In 87 CSF samples S. pneumoniae and N. meningitidis were identified by culture and/or 16 S rRNA in 14 and 10 samples and by qmPCR in 14 and 10 samples, respectively, giving a sensitivity of 100% and a specificity of 100% for both bacteria. The PCR provides increased

  13. Virulence phenotypes of low-passage clinical isolates of Nontypeable Haemophilus influenzae assessed using the chinchilla laniger model of otitis media

    Directory of Open Access Journals (Sweden)

    Hogg Justin

    2007-06-01

    Full Text Available Abstract Background The nontypeable Haemophilus influenzae (NTHi are associated with a spectrum of respiratory mucosal infections including: acute otitis media (AOM; chronic otitis media with effusion (COME; otorrhea; locally invasive diseases such as mastoiditis; as well as a range of systemic disease states, suggesting a wide range of virulence phenotypes. Genomic studies have demonstrated that each clinical strain contains a unique genic distribution from a population-based supragenome, the distributed genome hypothesis. These diverse clinical and genotypic findings suggest that each NTHi strain possesses a unique set of virulence factors that contributes to the course of the disease. Results The local and systemic virulence patterns of ten genomically characterized low-passage clinical NTHi strains (PittAA – PittJJ obtained from children with COME or otorrhea were stratified using the chinchilla model of otitis media (OM. Each isolate was used to bilaterally inoculate six animals and thereafter clinical assessments were carried out daily for 8 days by blinded observers. There was no statistical difference in the time it took for any of the 10 NTHi strains to induce otologic (local disease with respect to any or all of the other strains, however the differences in time to maximal local disease and the severity of local disease were both significant between the strains. Parameters of systemic disease indicated that the strains were not all equivalent: time to development of the systemic disease, maximal systemic scores and mortality were all statistically different among the strains. PittGG induced 100% mortality while PittBB, PittCC, and PittEE produced no mortality. Overall Pitt GG, PittII, and Pitt FF produced the most rapid and most severe local and systemic disease. A post hoc determination of the clinical origins of the 10 NTHi strains revealed that these three strains were of otorrheic origin, whereas the other 7 were from patients

  14. Antibiotic susceptibility in Streptococcus pneumoniae, Haemophilus influenzae and Streptococcus pyogenes in Pakistan: a review of results from the Survey of Antibiotic Resistance (SOAR) 2002-15.

    Science.gov (United States)

    Zafar, A; Hasan, R; Nizamuddin, S; Mahmood, N; Mukhtar, S; Ali, F; Morrissey, I; Barker, K; Torumkuney, D

    2016-05-01

    To investigate changes in the antibiotic susceptibility of Streptococcus pneumoniae, Haemophilus influenzae and Streptococcus pyogenes from the Survey of Antibiotic Resistance (SOAR) in community-acquired respiratory tract infections (CA-RTIs) between 2002 and 2015 in Pakistan. This is a review based on previously published studies from 2002-03, 2004-06 and 2007-09 and also new data from 2014-15. Susceptibility was determined by Etest(®) or disc diffusion according to CLSI and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints. A total of 706 isolates from CA-RTIs comprising 381 S. pneumoniae, 230 H. influenzae and 95 S. pyogenes were collected between 2002 and 2015 and tested against a range of antibiotics. Antibiotic resistance in S. pneumoniae rose steeply from 2002 to 2009, with isolates non-susceptible to penicillin and macrolides increasing from 10% to 34.1% and from 13%-14% to 29.7%, respectively. Susceptibility to amoxicillin/clavulanic acid (and by inference amoxicillin) remained between 99.4% and 100% from 2002 to 2015. Over the years, the prevalence of susceptibility to cefuroxime was 98%-100% among S. pneumoniae. Resistance in S. pneumoniae to some older antibiotics between 2007 and 2009 was high (86.8% for trimethoprim/sulfamethoxazole and 57.2% for tetracycline). Between 2002 and 2015, ampicillin resistance (β-lactamase-positive strains) among H. influenzae has remained low (between 2.6% and 3.2%) and almost unchanged over the years (H. influenzae was not tested during 2004-06). For S. pyogenes isolates, macrolide resistance reached 22%; however, susceptibility to penicillin, amoxicillin/clavulanic acid and cefuroxime remained stable at 100%. In S. pneumoniae from Pakistan, there has been a clear reduction in susceptibility to key antibiotics since 2002, but not to amoxicillin/clavulanic acid (amoxicillin) or cefuroxime. However, susceptibility in H. influenzae has remained stable. Local antibiotic susceptibility/resistance data are essential to

  15. Lot-to-lot consistency, safety and immunogenicity of 3 lots of Haemophilus influenzae type b conjugate vaccine: results from a phase III randomized, multicenter study in infants.

    Science.gov (United States)

    Klein, Nicola P; Abu-Elyazeed, Remon; Cornish, Matthew; Leonardi, Michael L; Weiner, Leonard B; Silas, Peter E; Grogg, Stanley E; Varman, Meera; Frenck, Robert W; Cheuvart, Brigitte; Baine, Yaela; Miller, Jacqueline M; Leyssen, Maarten; Mesaros, Narcisa; Roy-Ghanta, Sumita

    2017-06-16

    Vaccination against Haemophilus influenzae type b (Hib) is included in routine pediatric immunization schedule in the United States. Previous vaccine shortages have created the need for additional options for Hib vaccination. This phase III, randomized, multi-centered study (NCT01000974) evaluated the safety and immunogenicity of a monovalent tetanus toxoid-conjugate Hib vaccine (Hib-TT) compared to a monovalent (Hib-TT control) and a combination Hib-TT vaccine. We hierarchically assessed lot-to-lot consistency of 3 Hib-TT lots and non-inferiority of Hib-TT to Hib-TT control. We co-administered routine pediatric vaccines with Hib-TT vaccines at 2, 4, 6months (primary vaccination) and 15-18months of age (booster vaccination). We recorded adverse events (AEs) for 4 (solicited) and 31days (unsolicited) post-vaccination and serious AEs (SAEs) throughout the study. Of 4009 enrolled children, 3086 completed booster phase. Lot-to-lot consistency was not demonstrated. The study met statistical criteria for non-inferiority of Hib-TT to Hib-TT control in terms of immune responses to Hib and co-administered vaccines' antigens, but not in terms of participants achieving post-primary vaccination anti-PRP levels ≥1µg/mL. Because of the hierarchical nature of the objectives, non-inferiority could not be established. In all groups, 92.5-96.7% and 99.6-100% of participants achieved anti-PRP levels ≥0.15µg/mL, while 78.3-89.8% and 97.9-99.1% had anti-PRP levels ≥1µg/mL, post-primary and post-booster vaccination, respectively. Immune responses to co-administered vaccines and reported incidence of AEs were comparable among groups. We recorded SAEs for 107/2963 (3.6%), 24/520 (4.6%), and 21/520 (4.0%) children post-primary vaccination, and 29/2337 (1.2%), 4/435 (0.9%), and 2/400 (0.5%) children post-booster vaccination with Hib-TT, Hib-TT control and combination Hib-TT vaccine, respectively; 6/5330 (0.1%) SAEs in the Hib-TT groups were considered vaccine-related. Hib

  16. The iron/heme regulated genes of Haemophilus influenzae: comparative transcriptional profiling as a tool to define the species core modulon.

    Science.gov (United States)

    Whitby, Paul W; Seale, Thomas W; VanWagoner, Timothy M; Morton, Daniel J; Stull, Terrence L

    2009-01-07

    Haemophilus influenzae requires heme for aerobic growth and possesses multiple mechanisms to obtain this essential nutrient. Although an understanding of the heme acquisition mechanisms of H. influenzae is emerging, significant gaps in our knowledge remain. Unresolved issues include the identities of all genes exhibiting altered transcription in response to iron and heme availability, the fraction of such genes functioning in iron/heme acquisition, and the heterogeneity of this gene set among clinical isolates. Previously we utilized H. influenzae strain Rd KW20 to demonstrate the utility of transcriptional profiling in defining the genes exhibiting altered transcription in response to environmental iron and heme levels. The current study expands upon those observations by determining the iron/heme modulons of two clinical isolates, the type b isolate 10810 and the nontypeable isolate R2866. These data are used to begin to define the core iron/heme modulon of the species. Microarray studies were performed to compare gene expression on transition from iron/heme-restricted to iron/heme-replete conditions for each isolate. Of 1820 ORFs on the array corresponding to R2866 genes, 363 were significantly differentially expressed: 233 were maximally transcribed under iron/heme-replete conditions and 130 under iron/heme-restricted conditions. Of the 1883 ORFs representing genes of strain 10810, 353 were significantly differentially transcribed: 150 were preferentially transcribed under iron/heme-replete conditions and 203 under iron/heme-restricted conditions. Comparison of the data sets indicated that 163 genes exhibited similar regulation in both isolates and that 74 of these exhibited similar patterns of regulation in Rd KW20. These comprise the putative core iron/heme modulon. This study provides evidence for a conserved core of H. influenzae genes the transcription of which is altered by the availability of iron and/or heme in the growth environment. Elucidation of

  17. Ecological Exposure Research: Water

    Science.gov (United States)

    Overview of ecological exposure water research, including invasive species, Functional Process Zones (FPZs), biomarkers, pharmaceuticals in water, headwater streams, DNA barcoding, wetland ecosystem services, and sediment remediation.

  18. Exposure assessment of trichloroethylene.

    Science.gov (United States)

    Wu, C; Schaum, J

    2000-01-01

    This article reviews exposure information available for trichloroethylene (TCE) and assesses the magnitude of human exposure. The primary sources releasing TCE into the environment are metal cleaning and degreasing operations. Releases occur into all media but mostly into the air due to its volatility. It is also moderately soluble in water and can leach from soils into groundwater. TCE has commonly been found in ambient air, surface water, and groundwaters. The 1998 air levels in microg/m(3) across 115 monitors can be summarized as follows: range = 0.01-3.9, mean = 0.88. A California survey of large water utilities in 1984 found a median concentration of 3.0 microg/L. General population exposure to TCE occurs primarily by inhalation and water ingestion. Typical average daily intakes have been estimated as 11-33 microg/day for inhalation and 2-20 microg/day for ingestion. A small portion of the population is expected to have elevated exposures as a result of one or more of these pathways: inhalation exposures to workers involved in degreasing operations, ingestion and inhalation exposures occurring in homes with private wells located near disposal/contamination sites, and inhalation exposures to consumers using TCE products in areas of poor ventilation. More current and more extensive data on TCE levels in indoor air, water, and soil are needed to better characterize the distribution of background exposures in the general population and elevated exposures in special subpopulations. Images Figure 1 PMID:10807565

  19. Monitoring of radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-02-01

    The guide specifies the requirements for the monitoring of radiation exposure in instances where radiation is used. In addition to workers, the guide covers students, apprentices and visitors. The guide shall also apply to exposure from natural radiation. However, the monitoring of radiation exposure in nuclear power plants is dealt with in YVL Guide 7.10 and 7.11. The guide defines the concepts relevant to the monitoring of radiation exposure and provides guidelines for determining the necessity of monitoring and subsequently arranging such in different operations. In addition, the guide specifies the criteria for the approval and regulatory control of the dosimetric service.

  20. Conflict exposure and competitiveness

    NARCIS (Netherlands)

    Cecchi, Francesco; Leuveld, Koen; Voors, Maarten

    2016-01-01

    We use data from a street football tournament and a series of lab-in-field experiments in postconflict Sierra Leone to examine the impact of exposure to conflict violence on competitive behavior. We find that football players who experienced more intense exposure to violence are more likely to get a

  1. Mercury exposure in Ireland

    DEFF Research Database (Denmark)

    Cullen, Elizabeth; Evans, David S; Davidson, Fred

    2014-01-01

    BACKGROUND: Monitoring of human exposure to mercury is important due to its adverse health effects. This study aimed to determine the extent of mercury exposure among mothers and their children in Ireland, and to identify factors associated with elevated levels. It formed part of the Demonstration...

  2. Aggregate Exposure Pathway Workshop

    Science.gov (United States)

    Recognizing the growing demands for conducting rapid, cost-effective, and reliable exposure assessment on the thousands of chemicals in commerce, a committee convened by the National Research Council (NRC) developed its vision for exposure science in the 21st century. A necessary...

  3. Dermal exposure assessment techniques.

    Science.gov (United States)

    Fenske, R A

    1993-12-01

    Exposure of the skin to chemical substances can contribute significantly to total dose in many workplace situations, and its relative importance will increase when airborne occupational exposure limits are reduced, unless steps to reduce skin exposure are undertaken simultaneously. Its assessment employs personal sampling techniques to measure skin loading rates, and combines these measurements with models of percutaneous absorption to estimate absorbed dose. Knowledge of dermal exposure pathways is in many cases fundamental to hazard evaluation and control. When the skin is the primary contributor to absorbed dose, dermal exposure measurements and biological monitoring play complementary roles in defining occupational exposures. Exposure normally occurs by one of three pathways: (i) immersion (direct contact with a liquid or solid chemical substance); (ii) deposition of aerosol or uptake of vapour through the skin; or (iii) surface contact (residue transfer from contaminated surfaces). Sampling methods fall into three categories: surrogate skin; chemical removal; and fluorescent tracers. Surface sampling represents a supplementary approach, providing an estimate of dermal exposure potential. Surrogate skin techniques involve placing a chemical collection medium on the skin. Whole-body garment samplers do not require assumptions relating to distribution, an inherent limitation of patch sampling. The validity of these techniques rests on the ability of the sampling medium to capture and retain chemicals in a manner similar to skin. Removal techniques include skin washing and wiping, but these measure only what can be removed from the skin, not exposure: laboratory removal efficiency studies are required for proper interpretation of data. Fluorescent tracer techniques exploit the visual properties of fluorescent compounds, and combined with video imaging make quantification of dermal exposure patterns possible, but the need to introduce a chemical substance (tracer

  4. The first dose of a Haemophilus influenzae type b conjugate vaccine reactivates memory B cells: evidence for extensive clonal selection, intraclonal affinity maturation, and multiple isotype switches to IgA2

    DEFF Research Database (Denmark)

    Hougs, L; Juul, L; Ditzel, H J

    1999-01-01

    The Ab response of a healthy adult to the first dose of a Haemophilus influenzae type b capsular polysaccharide (HibCP) conjugate vaccine was studied at the level of Ig gene usage by circulating Ab-secreting cells. Forty-one IgA and 17 IgG mRNA sequences were obtained. The major part...... selected, and expanded population of cells existing before vaccination, i.e., memory B cells. The dominating heavy and light chains of the response were combined in a Fab that bound HibCP. It was shown that the shared heavy and light chain mutations increased the affinity for HibCP considerably, indicating...... that the clonal selection had been driven by affinity. Pre-existing memory cells in unvaccinated adults may explain several features of Ab responses to polysaccharide vaccines and may play a role in acquiring the ability to respond to pure polysaccharides during infancy....

  5. Efficacy of pneumococcal nontypable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV in young Latin American children: A double-blind randomized controlled trial.

    Directory of Open Access Journals (Sweden)

    Miguel W Tregnaghi

    2014-06-01

    Full Text Available The relationship between pneumococcal conjugate vaccine-induced antibody responses and protection against community-acquired pneumonia (CAP and acute otitis media (AOM is unclear. This study assessed the impact of the ten-valent pneumococcal nontypable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV on these end points. The primary objective was to demonstrate vaccine efficacy (VE in a per-protocol analysis against likely bacterial CAP (B-CAP: radiologically confirmed CAP with alveolar consolidation/pleural effusion on chest X-ray, or non-alveolar infiltrates and C-reactive protein ≥ 40 µg/ml; other protocol-specified outcomes were also assessed.This phase III double-blind randomized controlled study was conducted between 28 June 2007 and 28 July 2011 in Argentine, Panamanian, and Colombian populations with good access to health care. Approximately 24,000 infants received PHiD-CV or hepatitis control vaccine (hepatitis B for primary vaccination, hepatitis A at booster at 2, 4, 6, and 15-18 mo of age. Interim analysis of the primary end point was planned when 535 first B-CAP episodes, occurring ≥2 wk after dose 3, were identified in the per-protocol cohort. After a mean follow-up of 23 mo (PHiD-CV, n = 10,295; control, n = 10,201, per-protocol VE was 22.0% (95% CI: 7.7, 34.2; one-sided p = 0.002 against B-CAP (conclusive for primary objective and 25.7% (95% CI: 8.4%, 39.6% against World Health Organization-defined consolidated CAP. Intent-to-treat VE was 18.2% (95% CI: 5.5%, 29.1% against B-CAP and 23.4% (95% CI: 8.8%, 35.7% against consolidated CAP. End-of-study per-protocol analyses were performed after a mean follow-up of 28-30 mo for CAP and invasive pneumococcal disease (IPD (PHiD-CV, n = 10,211; control, n = 10,140 and AOM (n = 3,010 and 2,979, respectively. Per-protocol VE was 16.1% (95% CI: -1.1%, 30.4%; one-sided p = 0.032 against clinically confirmed AOM, 67.1% (95% CI: 17.0%, 86.9% against vaccine serotype clinically

  6. Frequency of apnea, bradycardia, and desaturations following first diphtheria-tetanus-pertussis-inactivated polio-Haemophilus influenzae type B immunization in hospitalized preterm infants

    Directory of Open Access Journals (Sweden)

    Spady Donald W

    2006-06-01

    Full Text Available Abstract Background Adverse cardiorespiratory events including apnea, bradycardia, and desaturations have been described following administration of the first diphtheria-tetanus-pertussis-inactivated polio-Haemophilus influenzae type B (DTP-IPV-Hib immunization to preterm infants. The effect of the recent substitution of acellular pertussis vaccine for whole cell pertussis vaccine on the frequency of these events requires further study. Methods Infants with gestational age of ≤ 32 weeks who received their first DTP-IPV-Hib immunization prior to discharge from two Edmonton Neonatal Intensive Care Units January 1, 1996 to November 30, 2000 were eligible for the study. Each immunized infant was matched by gestational age to one control infant. The number of episodes of apnea, bradycardia, and/or desaturations (ABD and the treatment required for these episodes in the 72 hours prior to and 72 hours post-immunization (for the immunized cohort or at the same post-natal age (for controls was recorded. Results Thirty-four infants who received DTP-IPV-Hib with whole cell pertussis vaccine, 90 infants who received DTP-IPV-Hib with acellular pertussis vaccine, and 124 control infants were entered in the study. Fifty-six immunized infants (45.1% and 36 control infants (29.0% had a resurgence of or increased ABD in the 72 hours post-immunization in the immunized infants and at the same post-natal age in the controls with an adjusted odds ratio for immunized infants of 2.41 (95% CI 1.29,4.51 as compared to control infants. The incidence of an increase in adverse cardiorespiratory events post-immunization was the same in infants receiving whole cell or acellular pertussis vaccine (44.1% versus 45.6%. Eighteen immunized infants (14.5% and 51 control infants (41.1% had a reduction in ABD in the 72 hours post- immunization or at the equivalent postnatal age in controls for an odds ratio of 0.175 (95%CI 0.08, 0.39. The need for therapy of ABD in the immunized

  7. Frequency of apnea, bradycardia, and desaturations following first diphtheria-tetanus-pertussis-inactivated polio-Haemophilus influenzae type B immunization in hospitalized preterm infants

    Science.gov (United States)

    Lee, Jackie; Robinson, Joan L; Spady, Donald W

    2006-01-01

    Background Adverse cardiorespiratory events including apnea, bradycardia, and desaturations have been described following administration of the first diphtheria-tetanus-pertussis-inactivated polio-Haemophilus influenzae type B (DTP-IPV-Hib) immunization to preterm infants. The effect of the recent substitution of acellular pertussis vaccine for whole cell pertussis vaccine on the frequency of these events requires further study. Methods Infants with gestational age of ≤ 32 weeks who received their first DTP-IPV-Hib immunization prior to discharge from two Edmonton Neonatal Intensive Care Units January 1, 1996 to November 30, 2000 were eligible for the study. Each immunized infant was matched by gestational age to one control infant. The number of episodes of apnea, bradycardia, and/or desaturations (ABD) and the treatment required for these episodes in the 72 hours prior to and 72 hours post-immunization (for the immunized cohort) or at the same post-natal age (for controls) was recorded. Results Thirty-four infants who received DTP-IPV-Hib with whole cell pertussis vaccine, 90 infants who received DTP-IPV-Hib with acellular pertussis vaccine, and 124 control infants were entered in the study. Fifty-six immunized infants (45.1%) and 36 control infants (29.0%) had a resurgence of or increased ABD in the 72 hours post-immunization in the immunized infants and at the same post-natal age in the controls with an adjusted odds ratio for immunized infants of 2.41 (95% CI 1.29,4.51) as compared to control infants. The incidence of an increase in adverse cardiorespiratory events post-immunization was the same in infants receiving whole cell or acellular pertussis vaccine (44.1% versus 45.6%). Eighteen immunized infants (14.5%) and 51 control infants (41.1%) had a reduction in ABD in the 72 hours post- immunization or at the equivalent postnatal age in controls for an odds ratio of 0.175 (95%CI 0.08, 0.39). The need for therapy of ABD in the immunized infants was not

  8. Efficacy of Pneumococcal Nontypable Haemophilus influenzae Protein D Conjugate Vaccine (PHiD-CV) in Young Latin American Children: A Double-Blind Randomized Controlled Trial

    Science.gov (United States)

    Tregnaghi, Miguel W.; Sáez-Llorens, Xavier; López, Pio; Abate, Hector; Smith, Enrique; Pósleman, Adriana; Calvo, Arlene; Wong, Digna; Cortes-Barbosa, Carlos; Ceballos, Ana; Tregnaghi, Marcelo; Sierra, Alexandra; Rodriguez, Mirna; Troitiño, Marisol; Carabajal, Carlos; Falaschi, Andrea; Leandro, Ana; Castrejón, Maria Mercedes; Lepetic, Alejandro; Lommel, Patricia; Hausdorff, William P.; Borys, Dorota; Guiñazú, Javier Ruiz; Ortega-Barría, Eduardo; Yarzábal, Juan P.; Schuerman, Lode

    2014-01-01

    Background The relationship between pneumococcal conjugate vaccine–induced antibody responses and protection against community-acquired pneumonia (CAP) and acute otitis media (AOM) is unclear. This study assessed the impact of the ten-valent pneumococcal nontypable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV) on these end points. The primary objective was to demonstrate vaccine efficacy (VE) in a per-protocol analysis against likely bacterial CAP (B-CAP: radiologically confirmed CAP with alveolar consolidation/pleural effusion on chest X-ray, or non-alveolar infiltrates and C-reactive protein ≥ 40 µg/ml); other protocol-specified outcomes were also assessed. Methods and Findings This phase III double-blind randomized controlled study was conducted between 28 June 2007 and 28 July 2011 in Argentine, Panamanian, and Colombian populations with good access to health care. Approximately 24,000 infants received PHiD-CV or hepatitis control vaccine (hepatitis B for primary vaccination, hepatitis A at booster) at 2, 4, 6, and 15–18 mo of age. Interim analysis of the primary end point was planned when 535 first B-CAP episodes, occurring ≥2 wk after dose 3, were identified in the per-protocol cohort. After a mean follow-up of 23 mo (PHiD-CV, n = 10,295; control, n = 10,201), per-protocol VE was 22.0% (95% CI: 7.7, 34.2; one-sided p = 0.002) against B-CAP (conclusive for primary objective) and 25.7% (95% CI: 8.4%, 39.6%) against World Health Organization–defined consolidated CAP. Intent-to-treat VE was 18.2% (95% CI: 5.5%, 29.1%) against B-CAP and 23.4% (95% CI: 8.8%, 35.7%) against consolidated CAP. End-of-study per-protocol analyses were performed after a mean follow-up of 28–30 mo for CAP and invasive pneumococcal disease (IPD) (PHiD-CV, n = 10,211; control, n = 10,140) and AOM (n = 3,010 and 2,979, respectively). Per-protocol VE was 16.1% (95% CI: −1.1%, 30.4%; one-sided p = 0.032) against clinically confirmed AOM

  9. Contribution of ROB-1 and PBP3 mutations to the resistance phenotype of a β-lactamase-positive amoxicillin/clavulanic acid-resistant Haemophilus influenzae carrying plasmid pB1000 in Italy.

    Science.gov (United States)

    San Millan, Alvaro; Giufré, Maria; Escudero, Jose Antonio; Hidalgo, Laura; Gutierrez, Belen; Cerquetti, Marina; Gonzalez-Zorn, Bruno

    2011-01-01

    plasmid pB1000 bearing bla(ROB-1) is responsible for high-level β-lactam resistance in Haemophilus influenzae as well as in Pasteurella multocida and Haemophilus parasuis isolates from Spain. Here, we explore the presence of ROB-1 in Italy and investigate the relative contribution of penicillin-binding protein 3 (PBP3) mutations and ROB-1 to the β-lactam resistance phenotype in H. influenzae. the collection of the Italian Reference Laboratory of H. influenzae was investigated for ROB-1-positive isolates between 2004 and 2009. H. influenzae Rd KW20 was used as recipient for pB1000 electroporation and for mutagenesis of the ftsI gene encoding PBP3. the presence of plasmid pB1000 in a non-typeable H. influenzae isolated in Italy, BB1059, is reported in this work. This strain is not genetically related to the H. influenzae clinical isolates bearing pB1000 described in Spain. The sequence of ftsI from BB1059 revealed several mutations in the predicted amino acid sequence of PBP3. To determine the relative contribution of pB1000 and PBP3 mutations to the β-lactam resistance phenotype of BB1059, H. influenzae Rd KW20 was transformed with ftsI and/or pB1000 from BB1059. β-Lactam resistance profiles revealed the additive effect of pB1000 and PBP3 mutations conferring resistance to β-lactams, including amoxicillin/clavulanic acid and third-generation cephalosporins. intra-European spread of plasmid pB1000 among H. influenzae has been shown. The coexistence of plasmid pB1000 and mutations in PBP3 produces an additive resistance phenotype in H. influenzae.

  10. ECO Exposure Assessment Tools by Receptors and Exposure Factors - References

    Science.gov (United States)

    Eco-Box is a toolbox for exposure assessors. Its purpose is to provide a compendium of exposure assessment and risk characterization tools that will present comprehensive step-by-step guidance and links to relevant exposure assessment data bases

  11. ECO Exposure Assessment Tools by Exposure Pathways - References

    Science.gov (United States)

    Eco-Box is a toolbox for exposure assessors. Its purpose is to provide a compendium of exposure assessment and risk characterization tools that will present comprehensive step-by-step guidance and links to relevant exposure assessment data bases

  12. Variability in endotoxin exposure levels and consequences for exposure assessment

    NARCIS (Netherlands)

    Spaan, S.; Schinkel, J.; Wouters, I.M.; Preller, L.; Tielemans, E.; Nij, E.T.; Heederik, D.

    2008-01-01

    Objectives: Workers in many industries are exposed to endotoxins, which may cause adverse health effects. In exposure assessment, information about exposure variability is essential. However, variability in exposure has rarely been investigated for biological agents and more specifically for

  13. Pesticide-Exposure Matrix

    Science.gov (United States)

    The "Pesticide-exposure Matrix" was developed to help epidemiologists and other researchers identify the active ingredients to which people were likely exposed when their homes and gardens were treated for pests in past years.

  14. Nanotechnology and Exposure Science

    Science.gov (United States)

    LIOY, PAUL J.; NAZARENKO, YEVGEN; HAN, TAE WON; LIOY, MARY JEAN; MAINELIS, GEDIMINAS

    2014-01-01

    This article discusses the gaps in our understanding of human exposures to nanoparticles stemming from the use of nanotechnology-based consumer products by the general public. It also describes a series of steps that could be taken to characterize such exposures. The suggested steps include classification of the nanotechnology-based products, simulation of realistic exposure patterns, characterization of emissions, analysis of the duration of activities resulting in exposures, and consideration of the bioaccessibility of nanoparticles. In addition, we present a preliminary study with nanotechnology-based cosmetic powders where particle release was studied under realistic powder application conditions. The data demonstrated that when nanotechnology-based cosmetic powders were used, there was a potential for inhaling airborne particles ranging in size from tens of nanometers to tens of micrometers. PMID:21222382

  15. Contamination vs. Exposure

    Science.gov (United States)

    ... Health Matters Information on Specific Types of Emergencies Contamination vs. exposure Recommend on Facebook Tweet Share Compartir ... contaminate their surroundings and personal property. Types of Contamination Internal Contamination Internal contamination occurs when people swallow ...

  16. Natural Weathering Exposure Station

    Data.gov (United States)

    Federal Laboratory Consortium — The Corps of Engineers' Treat Island Natural Weathering Exposure Station is a long-term natural weathering facility used to study concrete durability. Located on the...

  17. Poinsettia plant exposure

    Science.gov (United States)

    Christmas flower poisoning; Lobster plant poisoning; Painted leaf poisoning ... Leaves, stem, sap of the poinsettia plant ... Poinsettia plant exposure can affect many parts of the body. EYES (IF DIRECT CONTACT OCCURS) Burning Redness STOMACH AND ...

  18. Insecticide Exposure in Parkinsonism

    National Research Council Canada - National Science Library

    Bloomquist, Jeffrey

    2003-01-01

    Behavioral, neurochemical, and immunocytochemical studies are characterizing the possible role of insecticide exposure in the etiology of Parkinson's disease as it may relate to Gulf War Syndrome. Chlorpyrifos (CP) and/or permethrin (PM...

  19. Insecticide Exposure in Parkinsonism

    National Research Council Canada - National Science Library

    Bloomquist, Jeffrey

    2001-01-01

    Behavioral, neurochemical, and immunocytochemical studies characterized the possible role of insecticide exposure in the etiology of Parkinson's disease as it may relate to Gulf War Syndrome. Chlorpyrifos (CP) and permethrin (PM...

  20. Insecticide Exposure in Parkinsonism

    National Research Council Canada - National Science Library

    Bloomquist, Jeffrey

    2002-01-01

    Behavioral, neurochemical, and immunocytochemical studies characterized the possible role of insecticide exposure in the etiology of Parkinson's disease as it may relate to Gulf War Syndrome. Chlorpyrifos (CP) and permethrin (PM...

  1. Radiation exposure and pregnancy.

    Science.gov (United States)

    Labant, Amy; Silva, Christina

    2014-01-01

    Radiological exposure from nuclear power reactor accidents, transportation of nuclear waste accidents, industrial accidents, or terrorist activity may be a remote possibility, but it could happen. Nurses must be prepared to evaluate and treat pregnant women and infants who have been exposed to radiation, and to have an understanding of the health consequences of a nuclear or radiological incident. Pregnant women and infants are a special group of patients who need consideration when exposed to radiation. Initial care requires thorough assessment and decisions regarding immediate care needs. Ongoing care is based on type and extent of radiation exposure. With accurate, comprehensive information and education, nurses will be better prepared to help mitigate the effects of radiation exposure to pregnant women and infants following a radiological incident. Information about radiation, health effects of prenatal radiation exposure, assessment, patient care, and treatment of pregnant women and infants are presented.

  2. Radiation Exposure and Pregnancy

    Science.gov (United States)

    ... Updated: June 2017 Health Physics Society Specialists in Radiation Safety Radiation Exposure and Pregnancy The birth of a child ... experience. It is In addition to unavoidable background radiation, one hard to prepare yourself for the joys— ...

  3. Personal Chemical Exposure informatics

    Science.gov (United States)

    Chemical Exposure science is the study of human contact with chemicals (from manufacturing facilities, everyday products, waste) occurring in their environments and advances knowledge of the mechanisms and dynamics of events that cause or prevent adverse health outcomes. (adapted...

  4. Inhalation exposure methodology.

    OpenAIRE

    Phalen, R F; Mannix, R C; Drew, R T

    1984-01-01

    Modern man is being confronted with an ever-increasing inventory of potentially toxic airborne substances. Exposures to these atmospheric contaminants occur in residential and commercial settings, as well as in the workplace. In order to study the toxicity of such materials, a special technology relating to inhalation exposure systems has evolved. The purpose of this paper is to provide a description of the techniques which are used in exposing laboratory subjects to airborne particles and ga...

  5. Autoimmunity and Asbestos Exposure

    Directory of Open Access Journals (Sweden)

    Jean C. Pfau

    2014-01-01

    Full Text Available Despite a body of evidence supporting an association between asbestos exposure and autoantibodies indicative of systemic autoimmunity, such as antinuclear antibodies (ANA, a strong epidemiological link has never been made to specific autoimmune diseases. This is in contrast with another silicate dust, crystalline silica, for which there is considerable evidence linking exposure to diseases such as systemic lupus erythematosus, systemic sclerosis, and rheumatoid arthritis. Instead, the asbestos literature is heavily focused on cancer, including mesothelioma and pulmonary carcinoma. Possible contributing factors to the absence of a stronger epidemiological association between asbestos and autoimmune disease include (a a lack of statistical power due to relatively small or diffuse exposure cohorts, (b exposure misclassification, (c latency of clinical disease, (d mild or subclinical entities that remain undetected or masked by other pathologies, or (e effects that are specific to certain fiber types, so that analyses on mixed exposures do not reach statistical significance. This review summarizes epidemiological, animal model, and in vitro data related to asbestos exposures and autoimmunity. These combined data help build toward a better understanding of the fiber-associated factors contributing to immune dysfunction that may raise the risk of autoimmunity and the possible contribution to asbestos-related pulmonary disease.

  6. A cohort study of developmental polychlorinated biphenyl (PCB) exposure in relation to post-vaccination antibody response at 6-months of age

    Energy Technology Data Exchange (ETDEWEB)

    Jusko, Todd A., E-mail: juskota@niehs.nih.gov [Epidemiology Branch, National Institute of Environmental Health Sciences, PO Box 12233, MD A3-05, 111 T.W. Alexander Dr, Rall Bldg 101, Rm A361, Research Triangle Park, NC 27709-2233 (United States); Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA (United States); De Roos, Anneclaire J.; Schwartz, Stephen M. [Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA (United States); Program in Epidemiology, Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA (United States); Paige Lawrence, B. [Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY (United States); Palkovicova, Lubica [Department of Environmental Medicine, Slovak Medical University, Bratislava (Slovakia); Nemessanyi, Tomas [Department of Immunology and Immunotoxicology, Slovak Medical University, Bratislava (Slovakia); Drobna, Beata; Fabisikova, Anna; Kocan, Anton [Department of Toxic Organic Pollutants, Slovak Medical University, Bratislava (Slovakia); Sonneborn, Dean [Department of Public Health Sciences, University of California, Davis, CA (United States); Jahnova, Eva [Department of Immunology and Immunotoxicology, Slovak Medical University, Bratislava (Slovakia); Kavanagh, Terrance J. [Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA (United States); Trnovec, Tomas [Department of Toxic Organic Pollutants, Slovak Medical University, Bratislava (Slovakia); Hertz-Picciotto, Irva [Department of Public Health Sciences, University of California, Davis, CA (United States)

    2010-05-15

    Background: Extensive experimental data in animals indicate that exposure to polychlorinated biphenyls (PCBs) during pregnancy leads to changes in offspring immune function during the postnatal period. Whether developmental PCB exposure influences immunologic development in humans has received little study. Methods: The study population was 384 mother-infant pairs recruited from two districts of eastern Slovakia for whom prospectively collected maternal, cord, and 6-month infant blood specimens were available. Several PCB congeners were measured in maternal, cord, and 6-month infant sera by high-resolution gas chromatography with electron capture detection. Concentrations of IgG-specific anti-haemophilus influenzae type b, tetanus toxoid, and diphtheria toxoid were assayed in 6-month infant sera using ELISA methods. Multiple linear regression was used to estimate the relation between maternal, cord, and 6-month infant PCB concentrations and the antibody concentrations evaluated at 6-months of age. Results: Overall, there was little evidence of an association between infant antibody concentrations and PCB measures during the pre- and early postnatal period. In addition, our results did not show specificity in terms of associations limited to a particular developmental period (e.g. pre- vs. postnatal), a particular antibody, or a particular PCB congener. Conclusions: At the PCB concentrations measured in this cohort, which are high relative to most human populations today, we did not detect an association between maternal or early postnatal PCB exposure and specific antibody responses at 6-months of age.

  7. Impact of Haemophilus influenzae type B (Hib) and viral influenza vaccinations in pregnancy for improving maternal, neonatal and infant health outcomes.

    Science.gov (United States)

    Salam, Rehana A; Das, Jai K; Dojo Soeandy, Chesarahmia; Lassi, Zohra S; Bhutta, Zulfiqar A

    2015-06-09

    Infections during pregnancy confers increased risk of maternal and perinatal morbidity and mortality. However, the case for advocating Haemophilus influenzae type B (Hib) and viral Influenza vaccinations in pregnancy is still debatable. To assess the impact of Hib and viral Influenza vaccinations during pregnancy on maternal, neonatal and infant health outcomes compared to placebo/control. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (29 January 2015) and reference lists of retrieved studies. All randomised controlled clinical trials (including cluster-randomised trials) and quasi-randomised trials evaluating Hib or viral influenza vaccination during pregnancy compared with no vaccination or placebo. Two review authors independently assessed trials for inclusion, risk of bias and extracted data. Data were checked for accuracy. Two trials were included this review. One (involving 213 women and 213 neonates) evaluated the impact of Hib vaccination during pregnancy and the other study (involving 2116 women and 2049 neonates) evaluated the impact of viral influenza vaccination during pregnancy. Overall, the HiB vaccination trial was judged to be at 'high risk of bias' due to inadequate randomisation while the other trial was judged to be at 'low risk of bias'. Hib vaccination during pregnancy versus placeboOne trial involving 213 women and 213 neonates evaluating the impact of Hib vaccination during pregnancy was included under this comparison. The study did not report on any of this review's prespecified primary outcomes (including mortality, respiratory tract infection and sepsis) or secondary outcomes (including adverse events) except preterm delivery. There was no clear difference between the Hib vaccination and placebo control groups in terms of preterm delivery (risk ratio (RR) 1.28, 95% confidence interval (CI) 0.12 to 13.86, one study, 213 participants), fetal distress (RR 1.23, 95% CI 0.67 to 2.26, one study, 213 infants

  8. Relación costo-efectividad de la vacuna contra Haemophilus influenzae tipo b en niños menores de dos años de edad en Colombia The cost-effectiveness of Haemophilus influenzae type b vaccine for children under 2 years of age in Colombia

    Directory of Open Access Journals (Sweden)

    Nelson Alvis Guzmán

    2006-10-01

    Full Text Available OBJETIVOS: Las vacunas conjugadas contra Haemophilus influenzae tipo b (Hib son la herramienta más importante para prevenir la mayoría de las enfermedades invasoras producidas por dicho patógeno, pero debido a su costo, aún no se han introducido mundialmente de manera masiva. En el presente estudio se determinó la relación costo-efectividad de una vacuna contra Hib para prevenir la neumonía y la meningitis bacterianas en niños menores de 2 años en Colombia. MÉTODOS: Se estimaron los costos directos e indirectos de la neumonía y la meningitis hospitalaria y siguiendo las recomendaciones de la Organización Mundial de la Salud (OMS, la relación costo-efectividad de los programas de vacunación contra Hib. Se estimaron también las razones de costos por caso evitado de enfermedad invasora por Hib y el costo por año de vida salvado en dos situaciones hipotéticas: con vacunación contra Hib (cobertura vacunal: 90% y sin vacunación. RESULTADOS: El costo medio del tratamiento hospitalario de un caso de neumonía fue de 611,5 dólares estadounidenses (US$ (intervalo de confianza del 95% [IC95%]: 532,2 - 690,8, el costo medio del tratamiento hospitalario de un caso de meningitis fue de US$ 848,9 (IC95%: 716,8 - 981,0 y el costo por caso evitado de enfermedad invasora por Hib, de US$ 316,7 (IC95%: 294,2 - 339,2. La relación costo-efectividad en la hipótesis con vacunación fue de 2,38, frente a 3,81 en la hipótesis sin vacunación. CONCLUSIÓN: La aplicación de un programa adecuado de vacunación contra Hib en Colombia puede prevenir cerca de 25 000 casos de enfermedad invasora por año, lo que representa un ahorro de por lo menos US$ 15 millones anuales. Además, puede evitar cerca de 700 defunciones y salvar anualmente 44 054 años de vida.OBJECTIVE: Conjugate vaccines are the best public health tools available for preventing most invasive diseases caused by Haemophilus influenzae type b (Hib, but the high cost of the vaccines has so

  9. Etiology of bacterial meningitis among children aged 2-59 months in Salvador, Northeast Brazil, before and after routine use of Haemophilus influenzae type b vaccine Etiologia da meningite bacteriana em crianças com idade entre 2 e 59 meses em Salvador, Nordeste do Brasil, antes e depois do uso rotineiro da vacina para Haemophilus influenzae tipo b

    Directory of Open Access Journals (Sweden)

    Cristiana M. Nascimento-Carvalho

    2004-06-01

    Full Text Available OBJECTIVE: To describe the frequency of etiologic agents of bacterial meningitis (BM among children aged 2-59 months in a sample of patients in Salvador, Northeast Brazil, with emphasis on the frequency of BM of unknown etiology (BMUE, just before, during and after the implementation of routine immunization of infants with Haemophilus influenzae type b (Hib vaccination. METHOD: Demographic, clinical and cerebrospinal fluid (CSF information was collected from the chart of every patient, aged 2-59 months, whose CSF exam was performed at the CSF Lab - José Silveira Foundation, between January 1989 and December 2001. Every CSF exam was completely performed according to standard methods. The etiologic diagnosis was based on either culture and/or latex-agglutination test. When the agent was only seen on Gram stained smear, the diagnosis was descriptive. BMUE was defined as: glucose 100 mg / dl, white blood cell count > 20 cells / mm³, percentage of neutrophils > 80%. RESULTS: Of 1519 patients, 894 (58.9% had normal exams and BM was diagnosed in 95 (6.2%. Etiologic agents were: Hib (44.2%, meningococcus (13.7%, Gram-negative bacilli (11.6%, Mycobacterium tuberculosis (6.3%, pneumococcus (4.2%, other agents (4.2%; BMUE was diagnosed in 15.8% of cases with BM. By analysing the frequency of BMUE and Hib among all exams performed yearly, the peaks were recorded in 1989 (5.3% and 1990 (16.9%, respectively, decreasing to 0.7% and 0% in 2001. CONCLUSION: It is possible that the implementation of the conjugate Hib vaccine during the 1990's has been decreasing not only the occurrence of Hib meningitis but also of BMUE.OBJETIVO: Descrever a freqüência dos agentes etiológicos de meningite bacteriana (MB em amostra das crianças com idade entre 2 e 59 meses, em Salvador, Nordeste do Brasil, com ênfase na freqüência de MB de etiologia indeterminada (MBEI, antes, durante e após a implementação da imunização rotineira de lactentes com vacina para

  10. Defining "intermittent UVR exposure".

    Science.gov (United States)

    Bodekær, M; Philipsen, P A; Petersen, B; Heydenreich, J; Wulf, H C

    2016-08-31

    Cutaneous malignant melanoma (CMM) has been associated with "intermittent UVR exposure", which in previous studies has mainly been assessed by retrospective questionnaire data. Further, there is no uniform definition of the term "intermittent UVR exposure". We aimed to define and quantify "intermittent UVR exposure" by an objective measure. A broad study population of adults and children had data collected during a summer period. Data were personal UVR dosimetry measurements, from which the number of "intermittent days" was derived, sun behaviour diaries and retrospective questionnaires. Two definitions of intermittent UVR exposure were tested: (1) days when UVR dose exceeded 3 times individual average daily UVR dose, and (2) days when UVR dose exceeded individual constitutive skin type. Measures of nevi and lentigines were used as surrogates for CMM. Using the first definition based solely on UVR dosimetry data we found 1241 "intermittent days" out of a total of 17 277 days (7.2%) among 148 participants. The numbers for nevi and lentigo density were significantly predicted by the number of intermittent days (R(2) = 0.15 and R(2) = 0.40, p intermittent UVR exposure. This measure may provide a better prediction of solar skin damage and CMM than retrospective questionnaire data.

  11. Asbestos Exposure Assessment Database

    Science.gov (United States)

    Arcot, Divya K.

    2010-01-01

    Exposure to particular hazardous materials in a work environment is dangerous to the employees who work directly with or around the materials as well as those who come in contact with them indirectly. In order to maintain a national standard for safe working environments and protect worker health, the Occupational Safety and Health Administration (OSHA) has set forth numerous precautionary regulations. NASA has been proactive in adhering to these regulations by implementing standards which are often stricter than regulation limits and administering frequent health risk assessments. The primary objective of this project is to create the infrastructure for an Asbestos Exposure Assessment Database specific to NASA Johnson Space Center (JSC) which will compile all of the exposure assessment data into a well-organized, navigable format. The data includes Sample Types, Samples Durations, Crafts of those from whom samples were collected, Job Performance Requirements (JPR) numbers, Phased Contrast Microscopy (PCM) and Transmission Electron Microscopy (TEM) results and qualifiers, Personal Protective Equipment (PPE), and names of industrial hygienists who performed the monitoring. This database will allow NASA to provide OSHA with specific information demonstrating that JSC s work procedures are protective enough to minimize the risk of future disease from the exposures. The data has been collected by the NASA contractors Computer Sciences Corporation (CSC) and Wyle Laboratories. The personal exposure samples were collected from devices worn by laborers working at JSC and by building occupants located in asbestos-containing buildings.

  12. Cryptic exposure to arsenic.

    Science.gov (United States)

    Rossy, Kathleen M; Janusz, Christopher A; Schwartz, Robert A

    2005-01-01

    Arsenic is an odorless, colorless and tasteless element long linked with effects on the skin and viscera. Exposure to it may be cryptic. Although human intake can occur from four forms, elemental, inorganic (trivalent and pentavalent arsenic) and organic arsenic, the trivalent inorganic arsenicals constitute the major human hazard. Arsenic usually reaches the skin from occupational, therapeutic, or environmental exposure, although it still may be employed as a poison. Occupations involving new technologies are not exempt from arsenic exposure. Its acute and chronic effects are noteworthy. Treatment options exist for arsenic-induced pathology, but prevention of toxicity remains the main focus. Vitamin and mineral supplementation may play a role in the treatment of arsenic toxicity.

  13. Effectiveness of the 10-Valent Pneumococcal Nontypeable Haemophilus influenzae Protein D-Conjugated Vaccine (PHiD-CV) Against Carriage and Acute Otitis Media-A Double-Blind Randomized Clinical Trial in Finland.

    Science.gov (United States)

    Vesikari, Timo; Forsten, Aino; Seppä, Ilkka; Kaijalainen, Tarja; Puumalainen, Taneli; Soininen, Anu; Traskine, Magali; Lommel, Patricia; Schoonbroodt, Sonia; Hezareh, Marjan; Moreira, Marta; Borys, Dorota; Schuerman, Lode

    2016-09-01

    After administering the 10-valent pneumococcal polysaccharide nontypeable Haemophilus influenzae protein D-conjugated vaccine (PHiD-CV) to children aged 2-18 months, we observed a reduction in vaccine-type nasopharyngeal carriage, resulting in a reduction of overall pneumococcal nasopharyngeal carriage, which may be important for indirect vaccine effects. We noted a trend toward reduction of acute otitis media. This trial (ClinicalTrials.gov identifier NCT00839254), nested within a cluster-randomized double-blind invasive pneumococcal disease effectiveness study in Finland (ClinicalTrials.gov identifier NCT00861380), assessed the effectiveness of the 10-valent pneumococcal polysaccharide nontypeable Haemophilus influenzae protein D-conjugated vaccine (PHiD-CV or PCV10) against bacterial nasopharyngeal carriage and acute otitis media (AOM). Infants (aged 6 weeks to 6 months) received the PHiD-CV or a control vaccine (hepatitis B) (schedule 3+1 or 2+1). Nasopharyngeal swabs were collected at 4 time points post-vaccination from all of the infants and at pre-vaccination from a subset. Parent-reported physician-diagnosed AOM was assessed from first vaccination until last contact (mean follow-up, 18 months). Vaccine effectiveness (VE) was derived as (1 - relative risk)*100, accounting for cluster design in AOM analysis. Significant VE was assessed descriptively (positive lower limit of the non-adjusted 95% confidence interval [CI]). The vaccinated cohort included 5093 infants for carriage assessment and 4117 infants for AOM assessment. Both schedules decreased vaccine-serotype carriage, with a trend toward a lesser effect from the 2+1 schedule ( VE across timpoints 19%-56% [3+1] and 1%-38% [2+1]). Trends toward reduced pneumococcal carriage (predominantly vaccine serotypes 6B, 14, 19F, and 23F), decreased carriage of vaccine-related serotype 19A, and small increases at later time points (ages 14-15 months) in non-vaccine-serotype carriage were observed. No effects on

  14. John Deakin: Double Exposures

    Directory of Open Access Journals (Sweden)

    Paul Rousseau

    2015-11-01

    Full Text Available In this series of short films made by Jonathan Law, the art historian James Boaden, and the curator of The John Deakin Archive, Paul Rousseau, discuss the double-exposure images made by the photographer John Deakin (1912-1972 in the 1950s and 1960s. The films ask you, firstly, to look closely at the images being discussed. Each one begins with a sustained and intense shot of a single image before opening up to a wide-ranging discussion about Deakin, double exposures, and photography.

  15. Radiographic constant exposure technique

    DEFF Research Database (Denmark)

    Domanus, Joseph Czeslaw

    1985-01-01

    The constant exposure technique has been applied to assess various industrial radiographic systems. Different X-ray films and radiographic papers of two producers were compared. Special attention was given to fast film and paper used with fluorometallic screens. Radiographic image quality was tes...... was tested by the use of ISO wire IQI's and ASTM penetrameters used on Al and Fe test plates. Relative speed and reduction of kilovoltage obtained with the constant exposure technique were calculated. The advantages of fast radiographic systems are pointed out...

  16. Fetal Alcohol Exposure

    Science.gov (United States)

    ... categories: 4 » Fetal Alcohol Syndrome (FAS) » Partial FAS (pFAS) » Alcohol-Related Neurodevelopmental Disorder (ARND) » Alcohol-Related Birth ... either prenatally, after birth, or both Partial FAS (pFAS) Partial FAS (pFAS) involves prenatal alcohol exposure, and ...

  17. A Technique: Exposure Therapy

    Directory of Open Access Journals (Sweden)

    Serkan AKKOYUNLU

    2013-08-01

    Conclusion: Exposure with response prevention is a basic and effective technique. Every cognitive behavior therapist must be able to implement this technique and be cognizant of pearls of this procedure. (Journal of Cognitive Behavioral Psychotherapy and Research 2013, 2: 121-128 [JCBPR 2013; 2(2.000: 121-128

  18. Liquid sulfur mustard exposure.

    Science.gov (United States)

    Newmark, Jonathan; Langer, Janice M; Capacio, Benedict; Barr, John; McIntosh, Roger G

    2007-02-01

    A 35-year-old active duty service member sustained a 6.5% body surface area burn as a result of exposure to the chemical warfare agent sulfur mustard, which is the most severe mustard exposure of a U.S. military member since World War II that is known to us. New techniques were used to demonstrate the detectable persistence of mustard metabolites in the patient's blood for at least 41 days after exposure, validating these techniques for the first time for a human mustard patient; they were also used for the first time with human mustard blister fluid. The techniques extend eightfold the period of time that mustard exposure can be definitively diagnosed, compared with previous techniques. Although this patient's lesions were never life-threatening, he required 2 weeks of intensive burn care. He has been left with ongoing posttraumatic stress disorder and has had an incomplete dermatological recovery. In a major terrorist attack involving many patients exposed to sulfur mustard, care resources would be depleted quickly.

  19. Interacción del componente pertussis de células completas con los antígenos tetánico, Haemophilus influenzae tipo B y hepatitis B en ensayos de potencia para vacunas combinadas

    Directory of Open Access Journals (Sweden)

    Mario Landys

    2008-04-01

    Full Text Available Las vacunas combinadas permiten un grado de aceptación mayor entre la población, dado que se requiere de menos inmunizaciones para proteger contra las enfermedades infecciosas. Sin embargo, esto ha generado nuevos retos, ya que se han reportado numerosas interacciones entre los diferentes antígenos que conforman estas vacunas. El propósito del presente trabajo fue evaluar la interferencia potencial del componente pertussis de células completas sobre los ensayos para determinar la actividad biológica de otros antígenos como toxoide tetánico, Haemophilus influenzae tipo b (Hib y hepatitis B. Para ello se estudiaron mediante ensayos de potencia vacunas combinadas que contenían estos antígenos y se compararon con vacunas monovalentes. A su vez se prepararon adyuvaciones experimentales cuya composición permitió estimar adecuadamente la extensión y naturaleza de la interacción entre componentes. Se obtuvo que el componente pertussis incrementó significativamente la actividad biológica de Hib y tétanos, aunque esto puede depender mucho del modelo animal y el diseño experimental utilizado. En cuanto al antígeno de hepatitis B se demostró que pertussis inhibía la potencia de este antígeno, tanto in vitro como in vivo, aunque por mecanismos diferentes y de forma no significativa.

  20. IMMUNOGENICITY AND SAFETY OF QUINVAXEM® (DIPHTHERIA, TETANUS, WHOLE-CELL PERTUSSIS, HEPATITIS B AND HAEMOPHILUS INFLUENZAE TYPE B VACCINE) GIVEN TO VIETNAMESE INFANTS AT 2 TO 4 MONTHS OF AGE.

    Science.gov (United States)

    Huu, Tran Ngoc; Phuong, Nguyen Thi Minh; Toan, Nguyen Trong; Thang, Ho Vinh

    2015-07-01

    Vietnam plans to replace the routine childhood diphtheria, pertussis and tetanus combination (DPT) vaccine with a pentavalent vaccine. The present study was performed to assess the immunogenicity and safety of the combined diphtheria, tetanus, whole-cell pertussis, hepatitis B (HepB), and Haemophilus influenzae type b (Hib) (DTwP-HepB-Hib) Quinvaxem® vaccine in children. A total of 131 infants received the Quinvaxem® vaccine at 2, 3 and 4 months. Antibody levels were measured at baseline, at one month after the third injection and one year after the first injection. Seroprotection rates were high for each vaccine antigen at one month after the third dose: 93.1% for diphtheria, 98.5% for tetanus, 99.2% for pertussis (seroconversion rate), 93.1% for HepB, and 100% for Hib (anti-PRP ≥ 0.15 µg/ml). The rate of children with protective antibodies persisting at one year after the first dose was 88.4% for diphtheria, 49.6% for pertussis, 82.2% for tetanus, 76.7% for HepB and 97.7% for Hib (anti-PRP ≥ 0.15 µg/ml). The Quinvaxem® vaccine was well tolerated and has a low rate of adverse events. Quinvaxem® given at 2, 3 and 4 months of age was immunogenic and safe for primary immunization among infants in Vietnam.

  1. Pneumonia prevention: Cost-effectiveness analyses of two vaccines among refugee children aged under two years, Haemophilus influenzae type b-containing and pneumococcal conjugate vaccines, during a humanitarian emergency, Yida camp, South Sudan.

    Science.gov (United States)

    Gargano, Lisa M; Hajjeh, Rana; Cookson, Susan T

    2017-01-11

    By September 2013, war between Sudan and South Sudan resulted in >70,000 Sudanese refugees and high pneumonia incidence among the 20,000 refugees in Yida camp, South Sudan. Using Médecins Sans Frontières (MSF)-provided data and modifying our decision-tree models, we estimated if administering Haemophilus influenzae type b (Hib)-containing (pentavalent vaccine, also with diphtheria pertussis and tetanus [DPT] and hepatitis B) and pneumococcal conjugate (PCV) vaccines were cost-effective against hospitalized pneumonia. Among children vaccination, one- and two-doses of combined Hib-containing and PCV would avert an estimated 118 and 125 pneumonia cases, and 8.5 and 9.1 deaths, respectively. The cost per Disability-Adjusted-Life-Year averted for administering combined one- and two-doses was US$125 and US$209, respectively. MSF demonstrated that it was possible to administer these vaccines during an emergency and our analysis found it was highly cost-effective, even with just one-dose of either vaccine. Despite unknown etiology, there is strong field and now economic rationale for administering Hib and PCV during at least one humanitarian emergency. Published by Elsevier Ltd.

  2. Detection of Streptococcus pneumoniae and Haemophilus influenzae type B by real-time PCR from dried blood spot samples among children with pneumonia: a useful approach for developing countries.

    Directory of Open Access Journals (Sweden)

    Laura Selva

    Full Text Available Dried blood spot (DBS is a reliable blood collection method for storing samples at room temperature and easily transporting them. We have previously validated a Real-Time PCR for detection of Streptococcus pneumoniae in DBS. The objective of this study was to apply this methodology for the diagnosis of S. pneumoniae and Haemophilus influenzae b (Hib in DBS samples of children with pneumonia admitted to two hospitals in Mozambique and Morocco.Ply and wzg genes of S. pneumoniae and bexA gene of Hib, were used as targets of Real-Time PCR. 329 DBS samples of children hospitalized with clinical diagnosis of pneumonia were tested.Real-Time PCR in DBS allowed for a significant increase in microbiological diagnosis of S. pneumoniae and Hib. When performing blood bacterial culture, only ten isolates of S. pneumoniae and none of Hib were detected (3·0% positivity rate, IC95% 1·4-5·5%. Real-Time PCR from DBS samples increased the detection yield by 4x fold, as 30 S. pneumoniae and 11 Hib cases were detected (12·4% positivity rate, IC95% 9·0-16·5%; P<0·001.Real-Time PCR applied in DBS may be a valuable tool for improving diagnosis and surveillance of pneumonia caused by S. pneumoniae or Hib in developing countries.

  3. Doses from radiation exposure

    CERN Document Server

    Menzel, H G

    2012-01-01

    Practical implementation of the International Commission on Radiological Protection's (ICRP) system of protection requires the availability of appropriate methods and data. The work of Committee 2 is concerned with the development of reference data and methods for the assessment of internal and external radiation exposure of workers and members of the public. This involves the development of reference biokinetic and dosimetric models, reference anatomical models of the human body, and reference anatomical and physiological data. Following ICRP's 2007 Recommendations, Committee 2 has focused on the provision of new reference dose coefficients for external and internal exposure. As well as specifying changes to the radiation and tissue weighting factors used in the calculation of protection quantities, the 2007 Recommendations introduced the use of reference anatomical phantoms based on medical imaging data, requiring explicit sex averaging of male and female organ-equivalent doses in the calculation of effecti...

  4. Environmental exposure tracking sensor

    Science.gov (United States)

    Havens, Teresa; Everhart, Joel; McFerran, Jace

    2009-03-01

    Cornerstone Research Group Inc. (CRG) has developed environmental exposure tracking (EET) sensors using shape memory polymer (SMP) to monitor the degradation of perishable items, such as munitions, medicines or foods, by measuring the cumulative exposure to temperature and moisture. SMPs are polymers whose qualities have been altered to give them dynamic shape "memory" properties. Under thermal or moisture stimuli, SMP exhibits a radical change from a rigid thermoset to a highly flexible, elastic state. The dynamic response of the SMP can be tailored to match the degradation profile of the perishable item. SMP-based EET sensors require no digital memory or internal power supply and provide the capability of inexpensive, long-term life cycle monitoring thermal and moisture exposure over time. In a Phase I and II SBIR effort with the Navy, CRG demonstrated the feasibility of SMP-based EET sensor with two material systems. These material systems required different activation stimuli, heat or water vapor pressure. CRG developed the ability to tailor these materials to customize the dynamic response to match various degradation profiles of munitions. CRG optimized and characterized the SMP formulations and sensor design configuration to develop a suite of data from which any degradation profile can be met. CRG's EET sensors are capable of monitoring temperatures from -30 °C to 260 °C. The prototypes monitor cumulative thermal exposure and provide real-time information in a visually readable or a remotely interrogated version. CRG is currently scaling up the manufacture of the sensors for munitions reliability applications with the Navy.

  5. EXPOSURE ASSESSMENT AND FUTURE DIRECTIONS IN EXPOSURE SCIENCE

    Science.gov (United States)

    Exposure is the contact between a stressor and a human or ecological receptor. Risk analysis step in which receptor interaction with the exposure stressor of concern is evaluated. To assess exposure to a particular stressor we need to know - Properties of the stressor; Sources, p...

  6. Human Exposure Database System (HEDS)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Human Exposure Database System (HEDS) provides public access to data sets, documents, and metadata from EPA on human exposure. It is primarily intended for...

  7. The Promise of Exposure Science

    Science.gov (United States)

    Exposure science is the bedrock for protection of public health. It fundamentally informs decisions that relate to smart and sustainable design, prevention and mitigation of adverse exposures, and ultimately health protection.

  8. Total imprecision of exposure biomarkers: implications for calculating exposure limits

    DEFF Research Database (Denmark)

    Grandjean, Philippe; Budtz-Jørgensen, Esben

    2007-01-01

    BACKGROUND: Assessment of the imprecision of exposure biomarkers usually focuses on laboratory performance only. Unrecognized imprecision leads to underestimation of the true toxicity of the exposure. We have assessed the total imprecision of exposure biomarkers and the implications for calculation...... of exposure limits. METHODS: In a birth cohort study, mercury concentrations in cord blood, cord tissue, and maternal hair were used as biomarkers of prenatal methylmercury exposure. We determined their mutual correlations and their associations with the child's neurobehavioral outcome variables at age 7...... years. With at least three exposure parameters available, factor analysis and structural equation modeling could be applied to determine the total imprecision of each biomarker. The estimated imprecision was then applied to adjust benchmark dose calculations and the derived exposure limits. RESULTS...

  9. Human exposure to aluminium.

    Science.gov (United States)

    Exley, Christopher

    2013-10-01

    Human activities have circumvented the efficient geochemical cycling of aluminium within the lithosphere and therewith opened a door, which was previously only ajar, onto the biotic cycle to instigate and promote the accumulation of aluminium in biota and especially humans. Neither these relatively recent activities nor the entry of aluminium into the living cycle are showing any signs of abating and it is thus now imperative that we understand as fully as possible how humans are exposed to aluminium and the future consequences of a burgeoning exposure and body burden. The aluminium age is upon us and there is now an urgent need to understand how to live safely and effectively with aluminium.

  10. Association of secondhand smoke exposure with pediatric invasive bacterial disease and bacterial carriage: a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Chien-Chang Lee

    2010-12-01

    Full Text Available A number of epidemiologic studies have observed an association between secondhand smoke (SHS exposure and pediatric invasive bacterial disease (IBD but the evidence has not been systematically reviewed. We carried out a systematic review and meta-analysis of SHS exposure and two outcomes, IBD and pharyngeal carriage of bacteria, for Neisseria meningitidis (N. meningitidis, Haemophilus influenzae type B (Hib, and Streptococcus pneumoniae (S. pneumoniae.Two independent reviewers searched Medline, EMBASE, and selected other databases, and screened articles for inclusion and exclusion criteria. We identified 30 case-control studies on SHS and IBD, and 12 cross-sectional studies on SHS and bacterial carriage. Weighted summary odd ratios (ORs were calculated for each outcome and for studies with specific design and quality characteristics. Tests for heterogeneity and publication bias were performed. Compared with those unexposed to SHS, summary OR for SHS exposure was 2.02 (95% confidence interval [CI] 1.52-2.69 for invasive meningococcal disease, 1.21 (95% CI 0.69-2.14 for invasive pneumococcal disease, and 1.22 (95% CI 0.93-1.62 for invasive Hib disease. For pharyngeal carriage, summary OR was 1.68 (95% CI, 1.19-2.36 for N. meningitidis, 1.66 (95% CI 1.33-2.07 for S. pneumoniae, and 0.96 (95% CI 0.48-1.95 for Hib. The association between SHS exposure and invasive meningococcal and Hib diseases was consistent regardless of outcome definitions, age groups, study designs, and publication year. The effect estimates were larger in studies among children younger than 6 years of age for all three IBDs, and in studies with the more rigorous laboratory-confirmed diagnosis for invasive meningococcal disease (summary OR 3.24; 95% CI 1.72-6.13.When considered together with evidence from direct smoking and biological mechanisms, our systematic review and meta-analysis indicates that SHS exposure may be associated with invasive meningococcal disease. The

  11. Inactivation of the Thymidylate Synthase thyA in Non-typeable Haemophilus influenzae Modulates Antibiotic Resistance and Has a Strong Impact on Its Interplay with the Host Airways

    Directory of Open Access Journals (Sweden)

    Irene Rodríguez-Arce

    2017-06-01

    Full Text Available Antibacterial treatment with cotrimoxazol (TxS, a combination of trimethoprim and sulfamethoxazole, generates resistance by, among others, acquisition of thymidine auxotrophy associated with mutations in the thymidylate synthase gene thyA, which can modify the biology of infection. The opportunistic pathogen non-typeable Haemophilus influenzae (NTHi is frequently encountered in the lower airways of chronic obstructive pulmonary disease (COPD patients, and associated with acute exacerbation of COPD symptoms. Increasing resistance of NTHi to TxS limits its suitability as initial antibacterial against COPD exacerbation, although its relationship with thymidine auxotrophy is unknown. In this study, the analysis of 2,542 NTHi isolates recovered at Bellvitge University Hospital (Spain in the period 2010–2014 revealed 119 strains forming slow-growing colonies on the thymidine low concentration medium Mueller Hinton Fastidious, including one strain isolated from a COPD patient undergoing TxS therapy that was a reversible thymidine auxotroph. To assess the impact of thymidine auxotrophy in the NTHi-host interplay during respiratory infection, thyA mutants were generated in both the clinical isolate NTHi375 and the reference strain RdKW20. Inactivation of the thyA gene increased TxS resistance, but also promoted morphological changes consistent with elongation and impaired bacterial division, which altered H. influenzae self-aggregation, phosphorylcholine level, C3b deposition, and airway epithelial infection patterns. Availability of external thymidine contributed to overcome such auxotrophy and TxS effect, potentially facilitated by the nucleoside transporter nupC. Although, thyA inactivation resulted in bacterial attenuation in a lung infection mouse model, it also rendered a lower clearance upon a TxS challenge in vivo. Thus, our results show that thymidine auxotrophy modulates both the NTHi host airway interplay and antibiotic resistance, which

  12. Immunogenicity and safety of primary and booster vaccination with 2 investigational formulations of diphtheria, tetanus and Haemophilus influenzae type b antigens in a hexavalent DTPa-HBV-IPV/Hib combination vaccine in comparison with the licensed Infanrix hexa.

    Science.gov (United States)

    Vesikari, Timo; Rivera, Luis; Korhonen, Tiina; Ahonen, Anitta; Cheuvart, Brigitte; Hezareh, Marjan; Janssens, Winnie; Mesaros, Narcisa

    2017-07-03

    Safety and immunogenicity of 2 investigational formulations of diphtheria, tetanus and Haemophilus influenzae type b antigens of the combined diphtheria-tetanus-acellular pertussis-hepatitis B-inactivated poliomyelitis-Hib vaccine (DTPa-HBV-IPV/Hib) were evaluated in a Primary (NCT01248884) and a Booster vaccination (NCT01453998) study. In the Primary study, 721 healthy infants (randomized 1:1:1) received 3 doses of DTPa-HBV-IPV/Hib formulation A (DATAPa-HBV-IPV/Hib), or B (DBTBPa-HBV-IPV/Hib) or the licensed DTPa-HBV-IPV/Hib vaccine (Infanrix hexa, GSK; control group) at 2, 3, 4 months of age. Infants were planned to receive a booster dose at 12-15 months of age with the same formulation received in the Primary study; however, following high incidence of fever associated with the investigational formulations in the Primary study, the Booster study protocol was amended and all infants yet to receive a booster dose (N = 385) received the licensed vaccine. In the Primary study, non-inferiority of 3-dose vaccination with investigational formulations compared with the licensed vaccine was not demonstrated due to anti-pertactin failing to meet the non-inferiority criterion. Post-primary vaccination, most infants had seroprotective levels of anti-diphtheria (100% of infants), anti-tetanus antigens (100%), against hepatitis B (≥ 97.5% across groups), polyribosyl-ribitol-phosphate (≥ 88.0%) and poliovirus types 1-3 (≥ 90.5%). Seropositivity rates for each pertussis antigen were 100% in all groups. Higher incidence of fever (> 38°C) was reported in infants receiving the investigational formulations (Primary study: 75.0% [A] and 72.1% [B] vs 58.8% [control]; Booster study, before amendment: 49.4% and 46.6% vs 37.4%, respectively). The development of the investigational formulations was not further pursued.

  13. Safety, immunogenicity and persistence of immune response to the combined diphtheria, tetanus, acellular pertussis, poliovirus and Haemophilus influenzae type b conjugate vaccine (DTPa-IPV/Hib) administered in Chinese infants.

    Science.gov (United States)

    Li, Yanping; Li, Rong Cheng; Ye, Qiang; Li, Changgui; Liu, You Ping; Ma, Xiao; Li, Yanan; Zhao, Hong; Chen, Xiaoling; Assudani, Deepak; Karkada, Naveen; Han, Htay Htay; Van Der Meeren, Olivier; Mesaros, Narcisa

    2017-03-04

    We conducted 3 phase III, randomized, open-label, clinical trials assessing the safety, reactogenicity (all studies), immunogenicity (Primary vaccination study) and persistence of immune responses (Booster study) to the combined diphtheria, tetanus, pertussis, poliomyelitis, and Haemophilus influenzae type b vaccine (DTPa-IPV/Hib) in Chinese infants and toddlers. In the Pilot study (NCT00964028), 50 infants (randomized 1:1) received 3 doses of DTPa-IPV/Hib at 2-3-4 (Group A) or 3-4-5 months of age (Group B). In the Primary study (NCT01086423), 984 healthy infants (randomized 1:1:1) received 3 doses of DTPa-IPV/Hib at 2-3-4 (Group A) or 3-4-5 (Group B) months of age, or concomitant DTPa/Hib and poliomyelitis (IPV) vaccination at 2-3-4 months of age (Control group); 825 infants received a booster dose of DTPa/Hib and IPV at 18-24 months of age (Booster study; NCT01449812). In the Pilot study, unsolicited symptoms were more frequent in Group A (16 versus 1 infant; mostly upper respiratory tract infection and pyrexia); this observation was attributed to an epidemic outbreak of viral infections. Non-inferiority of 3-dose primary vaccination with DTPa-IPV/Hib over separately administered DTPa/Hib and IPV was demonstrated for Group A (primary objective). Similar antibody concentrations were observed in all groups, except for anti-polyribosyl-ribitol phosphate and anti-poliovirus types 1-3 which were higher in DTPa-IPV/Hib recipients. Protective antibody levels against all vaccine antigens remained high until booster vaccination. Three-dose vaccination with DTPa-IPV/Hib had a clinically acceptable safety profile.

  14. Impact of intermittent preventive treatment in pregnancy with azithromycin-containing regimens on maternal nasopharyngeal carriage and antibiotic sensitivity of Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus: a cross-sectional survey at delivery.

    Science.gov (United States)

    Unger, Holger W; Aho, Celestine; Ome-Kaius, Maria; Wangnapi, Regina A; Umbers, Alexandra J; Jack, Wanda; Lafana, Alice; Michael, Audrey; Hanieh, Sarah; Siba, Peter; Mueller, Ivo; Greenhill, Andrew R; Rogerson, Stephen J

    2015-04-01

    Sulfadoxine-pyrimethamine (SP) plus azithromycin (AZ) (SPAZ) has the potential for intermittent preventive treatment of malaria in pregnancy (IPTp), but its use could increase circulation of antibiotic-resistant bacteria associated with severe pediatric infections. We evaluated the effect of monthly SPAZ-IPTp compared to a single course of SP plus chloroquine (SPCQ) on maternal nasopharyngeal carriage and antibiotic susceptibility of Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus at delivery among 854 women participating in a randomized controlled trial in Papua New Guinea. Serotyping was performed, and antibiotic susceptibility was evaluated by disk diffusion and Etest. Potential risk factors for carriage were examined. Nasopharyngeal carriage at delivery of S. pneumoniae (SPAZ, 7.2% [30/418], versus SPCQ, 19.3% [84/436]; P<0.001) and H. influenzae (2.9% [12/418] versus 6.0% [26/436], P=0.028), but not S. aureus, was significantly reduced among women who had received SPAZ-IPTp. The number of macrolide-resistant pneumococcal isolates was small but increased in the SPAZ group (13.3% [4/30], versus SPCQ, 2.2% [2/91]; P=0.033). The proportions of isolates with serotypes covered by the 13-valent pneumococcal conjugate vaccine were similar (SPAZ, 10.3% [3/29], versus SPCQ, 17.6% [16/91]; P=0.352). Although macrolide-resistant isolates were rare, they were more commonly detected in women who had received SPAZ-IPTp, despite the significant reduction of maternal carriage of S. pneumoniae and H. influenzae observed in this group. Future studies on SPAZ-IPTp should evaluate carriage and persistence of macrolide-resistant S. pneumoniae and other pathogenic bacteria in both mothers and infants and assess the clinical significance of their circulation. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  15. Serum Antibody Response to Three Non-typeable Haemophilus influenzae Outer Membrane Proteins During Acute Otitis Media and Nasopharyngeal Colonization in Otitis Prone and Non-Otitis Prone Children

    Science.gov (United States)

    Kaur, Ravinder; Casey, Janet R.; Pichichero, Michael E.

    2011-01-01

    Non-typeable Haemophilus influenzae (NTHi) is the most common bacteria responsible for episodic acute otitis media (AOM; non-otitis prone), recurrent AOM (rAOM; otitis prone) and AOM treatment failure (AOMTF) in children. In this 3.5 years of prospective study, we measured the serum antibody response to outer membrane proteins D, P6 and OMP26 of NTHi in children with AOM (n= 26), rAOM (n= 32), AOMTF (n=27). The geometric mean titers (GMTs) of IgG at their acute AOM visit against protein D in otitis prone children were significantly lower compared to AOMTF (p value otitis prone (p value otitis prone children had significantly lower IgG levels to P6 compared to AOMTF children (p value otitis prone children had significantly lower IgG levels to OMP26 compared to AOMTF children (p value otitis prone and AOMTF children had no significant change in total IgG against all the three proteins, while non-otitis prone children had significant increases to protein D. Anti-Protein D, P6 and OMP26 antibody levels measured longitudinally during NP colonization between age 6 and 24 months in 10 otitis prone children and 150 non-otitis prone children showed otitis prone children compared to > 4 fold increases in the non-otitis prone children (p value otitis prone children mount less of an IgG serum antibody response toward Protein D, P6 and OMP26 after AOM which may account for recurrent infections. The data on acute sera of otitis prone versus non-otitis prone children and the acute-to-convalescence response in non-otitis prone children point to a possible link of anti-PD to protection. Moreover, the data suggest that otitis prone children should be evaluated for their responses to Protein D, P6 and OMP26 vaccine antigens of NTHi. PMID:21129398

  16. A multicenter prospective trial to asses a new real-time polymerase chain reaction for detection of Treponema pallidum, herpes simplex-1/2 and Haemophilus ducreyi in genital, anal and oropharyngeal ulcers.

    Science.gov (United States)

    Glatz, M; Juricevic, N; Altwegg, M; Bruisten, S; Komericki, P; Lautenschlager, S; Weber, R; Bosshard, P P

    2014-12-01

    Treponema pallidum, herpes simplex virus types 1 or 2 (HSV-1/2) and Haemophilus ducreyi are sexually transmitted pathogens that can cause genital, anal and oropharyngeal ulcers. Laboratory evaluation of these pathogens in ulcers requires different types of specimens and tests, increasing the risk of improper specimen handling and time lapse until analysis. We sought to develop a new real-time PCR (TP-HD-HSV1/2 PCR) to facilitate the detection of T. pallidum, HSV-1/2 and H. ducreyi in ulcers. The TP-HD-HSV1/2 PCR was tested (i) in a retrospective study on 193 specimens of various clinical origin and (ii) in a prospective study on 36 patients with genital, anal or oropharyngeal ulcers (ClinicalTrials.gov # NCT01688258). The results of the TP-HD-HSV1/2 PCR were compared with standard diagnostic methods (T. pallidum: serology, dark field microscopy; HSV-1/2: PCR; H. ducreyi: cultivation). Sensitivity and specificity of the TP-HD-HSV1/2 PCR for T. pallidum were both 100%, for HSV-1 100% and 98%, and for HSV-2 100% and 98%, respectively. T. pallidum and HSV-1/2 were detected in 53% and 22% of patients in the prospective study; H. ducreyi was not detected. In the prospective study, 5/19 (26%) specimens were true positive for T. pallidum in the TP-HD-HSV1/2 PCR but non-reactive in the VDRL. The TP-HD-HSV1/2 PCR is sensitive and specific for the detection of T. pallidum and HSV-1/2 in routine clinical practice and it appears superior to serology in early T. pallidum infections. © 2014 The Authors Clinical Microbiology and Infection © 2014 European Society of Clinical Microbiology and Infectious Diseases.

  17. The effect of season and vaccination for Glässer's disease and post-weaning Colibacillosis in an outdoor pig unit endemically infected with virulent strain of Haemophilus Parasuis serotype 5 and pathogenic Escherichia coli.

    Science.gov (United States)

    Karg, G; Bilkei, G

    2002-12-01

    The objective of this field trial was to determine if vaccination against Haemophilus parasuis serovar 5 (HPS 5) and pathogenic serotypes of Escherichia coli would improve nursery pig performance in an outdoor unit in different seasons. The unit was concurrently infected with HPS 5 and with different serotypes of E. coli. All piglets were born to HPS 5 vaccinated sows. The trial was carried out in four (two summer and two winter) groups. Group 1 (E. coli and HPS vaccinated, summer season) (n = 362): Piglets were vaccinated pre-weaning with inactivated E. coli-VT2e-toxin and post-weaning against HPS 5. Group 2 (non-vaccinated, summer season) (n = 349): Piglets were not vaccinated. Group 3 (E. coli and HPS vaccinated, winter season) (n = 358): The animals were analogously treated as Group 1. Group 4 (non-vaccinated, winter season) (n = 353): Piglets were not vaccinated. The following parameters were evaluated: A: average daily nursery weight gain (ADG), B: nursery mortality, C: feed efficiency (FE). No significant weight differences were detected within the vaccinated and non-vaccinated summer or winter raised groups of weaners. Summer raised weaners were significantly (Ppost-weaning Pfeed efficiency compared with the non-vaccinated winter raised animals. Non-significant ADG and FE differences were detectable between the summer raised vaccinated or non-vaccinated groups of pig. Winter raised non-vaccinated animals suffered significantly (P<0.05) higher nursery mortality (10.63%) compared to the winter raised vaccinated animals. In cases of concurrent infections with HPS 5 and with different serotypes of E. coli, especially during winter season, vaccination against both diseases is suggested.

  18. Immunogenicity and safety of an inactivated hepatitis A vaccine when coadministered with Diphtheria-tetanus-acellular pertussis and haemophilus influenzae type B vaccines in children 15 months of age.

    Science.gov (United States)

    Trofa, Andrew F; Klein, Nicola P; Paul, Ian M; Michaels, Marian G; Goessler, Mary; Chandrasekaran, Vijayalakshmi; Blatter, Mark

    2011-09-01

    This study (NCT00197236) evaluated the safety and immunogenicity of a hepatitis A virus (HAV) vaccine when coadministered with diphtheria-tetanus-acellular pertussis (DTaP) and Haemophilus influenzae type b (Hib) vaccines in children 15 months of age. This was an open-labeled, multicenter study with healthy subjects enrolled and randomized (1:1:1) into 3 treatment groups. A total of 394 subjects received the first study vaccinations at 15 months of age. Group HAV (N = 135) received 2 doses of HAV vaccine 6 to 9 months apart. Group HAV+DTaP+Hib (N = 127) received HAV vaccine coadministered with DTaP and Hib vaccines and the second dose of HAV vaccine, 6 to 9 months later. Group DTaP+Hib→HAV (N = 132) received the DTaP and Hib vaccines at 15 months of age, followed by HAV vaccine 30 days later and the second dose of HAV vaccine 7 to 10 months after the DTaP+Hib vaccines. Immune responses were evaluated before the first study vaccination and 30 days after each vaccine dose. Solicited, unsolicited, and serious adverse events were collected. After 2 doses of the HAV vaccine, all subjects in the 3 groups were seropositive. The geometric mean concentration of anti-HAV antibodies ranged between 1625.1 and 1904.4 mIU/mL. Coadministration of the 3 vaccines did not impact immunogenicity of the HAV, DTaP, or Hib vaccines. Vaccines were well tolerated in all groups. A 2-dose schedule of HAV vaccine was well tolerated and immunogenic when administered to children starting at 15 months of age. Immune responses to the DTaP or Hib vaccines were similar whether they were administered alone or were coadministered with the HAV vaccine.

  19. Immunization coverage and risk factors for failure to immunize within the Expanded Programme on Immunization in Kenya after introduction of new Haemophilus influenzae type b and hepatitis b virus antigens

    Directory of Open Access Journals (Sweden)

    Feikin Daniel R

    2006-05-01

    Full Text Available Abstract Background Kenya introduced a pentavalent vaccine including the DTP, Haemophilus influenzae type b and hepatitis b virus antigens in Nov 2001 and strengthened immunization services. We estimated immunization coverage before and after introduction, timeliness of vaccination and risk factors for failure to immunize in Kilifi district, Kenya. Methods In Nov 2002 we performed WHO cluster-sample surveys of >200 children scheduled for vaccination before or after introduction of pentavalent vaccine. In Mar 2004 we conducted a simple random sample (SRS survey of 204 children aged 9–23 months. Coverage was estimated by inverse Kaplan-Meier survival analysis of vaccine-card and mothers' recall data and corroborated by reviewing administrative records from national and provincial vaccine stores. The contribution to timely immunization of distance from clinic, seasonal rainfall, mother's age, and family size was estimated by a proportional hazards model. Results Immunization coverage for three DTP and pentavalent doses was 100% before and 91% after pentavalent vaccine introduction, respectively. By SRS survey, coverage was 88% for three pentavalent doses. The median age at first, second and third vaccine dose was 8, 13 and 18 weeks. Vials dispatched to Kilifi District during 2001–2003 would provide three immunizations for 92% of the birth cohort. Immunization rate ratios were reduced with every kilometre of distance from home to vaccine clinic (HR 0.95, CI 0.91–1.00, rainy seasons (HR 0.73, 95% CI 0.61–0.89 and family size, increasing progressively up to 4 children (HR 0.55, 95% CI 0.41–0.73. Conclusion Vaccine coverage was high before and after introduction of pentavalent vaccine, but most doses were given late. Coverage is limited by seasonal factors and family size.

  20. Defining "intermittent UVR exposure"

    DEFF Research Database (Denmark)

    Bodekær, Mette; Philipsen, Peter Alshede; Petersen, Bibi Øager

    2016-01-01

    Background: Cutaneous malignant melanoma (CMM) has been associated with “intermittent UVR exposure”, which in previous studies has mainly been assessed by retrospective questionnaire data. Further, there is no uniform definition of the term “intermittent UVR exposure”. Objectives: We aimed...... to define and quantify “intermittent UVR exposure” by an objective measure. Methods: A broad study population of adults and children had data collected during a summer period. Data were personal UVR dosimetry measurements, from which the number of “intermittent days” was derived, sun behaviour diaries...... and retrospective questionnaires. Two definitions of intermittent UVR exposure were tested: (1) days when UVR dose exceeded 3 times individual average daily UVR dose, and (2) days when UVR dose exceeded individual constitutive skin type. Measures of nevi and lentigines were used as surrogates for CMM. Results...