Prevalence and risk factors for Salmonella spp. colonization in broiler flocks in Shiraz, southern Iran

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Maryam Ansari-Lari

2014-04-01

Full Text Available Salmonella spp. are important food borne pathogens worldwide that frequently infect poultry flocks. This cross-sectional study was conducted to determine the prevalence of Salmonella spp. colonization in broiler flocks in Shiraz (southern Iran and to find the possible association of infection status with some potential risk factors including vaccination program and use of antibiotics. During October 2009 to April 2010, a total of 40 broiler flocks were selected in slaughterhouse and 20 cloacae contents were collected from each flock. Every five cloacae contents were pooled and investigated for Salmonella spp. using appropriate culture methods. The flock was considered positive if any of the pooled samples turned positive in culture. Statistical analysis was performed using multiple logistic regression. Nine out of 40 flocks (22.50%, 95% CI: 9-36 were positive for Salmonella spp. colonization. Nearly 75.00% of flock owners reported that they used antibiotics during production period, more frequently fluoroquinolones, combination of trimethoprim-sulfonamides (TMP/SU and tetracycline. Nearly 60.00% of the flocks which had used TMP/SU were positive for Salmonella spp. compared with 10.00% of the flocks which did not use this antibiotic (p = 0.006. Increasing flock age was associated with a decreased chance of Salmonella spp. detection (p = 0.003. In flocks which received infectious bronchitis vaccine, 36.00% were positive for Salmonella spp. whereas this was 15.00% for flocks which did not receive this vaccine (p = 0.08. Careful monitoring of antibiotics use and further studies to determine the most appropriate vaccination program in the field is recommended.

Vi-CRM 197 as a new conjugate vaccine against Salmonella Typhi.

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Micoli, F; Rondini, S; Pisoni, I; Proietti, D; Berti, F; Costantino, P; Rappuoli, R; Szu, S; Saul, A; Martin, L B

2011-01-17

An efficacious, low cost vaccine against typhoid fever, especially for young children, would make a major impact on disease burden in developing countries. The virulence capsular polysaccharide of Salmonella Typhi (Vi) coupled to recombinant mutant Pseudomonas aeruginosa exoprotein A (Vi-rEPA) has been shown to be highly efficacious. We investigated the use of carrier proteins included in infant vaccines, standardized the conjugation process and developed key assays required for routine lot release at production scale. Vi from a BSL1 organism, Citrobacter freundii, strain WR7011, was used as an alternative to Vi from S. Typhi. We showed that Vi conjugated to CRM(197), a non-toxic mutant of diphtheria toxin, widely used in commercial vaccines, was produced at high yield. Vi-CRM(197) proved immunogenic in animal studies, even without adjuvant. Thus, Vi-CRM(197) appears to be a suitable candidate for the development of a commercially viable, effective typhoid vaccine for developing countries. Copyright © 2010 Elsevier Ltd. All rights reserved.

Salmonella Control Programs in Denmark

DEFF Research Database (Denmark)

Wegener, Henrik Caspar; Hald, Tine; Wong, Danilo Lo Fo

2003-01-01

We describe Salmonella control programs of broiler chickens, layer hens, and pigs in Denmark. Major reductions in the incidence of foodborne human salmonellosis have occurred by integrated control of farms and food processing plants. Disease control has been achieved by monitoring the herds...... and flocks, eliminating infected animals, and diversifying animals (animals and products are processed differently depending on Salmonella status) and animal food products according to the determined risk. In 2001, the Danish society saved U.S.$25.5 million by controlling Salmonella. The total annual...... Salmonella control costs in year 2001 were U.S.$14.1 million (U.S.$0.075/kg of pork and U.S.$0.02/kg of broiler or egg). These costs are paid almost exclusively by the industry. The control principles described are applicable to most industrialized countries with modern intensive farming systems....

Multiple antigens of Yersinia pestis delivered by live recombinant attenuated Salmonella vaccine strains elicit protective immunity against plague.

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Sanapala, Shilpa; Rahav, Hannah; Patel, Hetal; Sun, Wei; Curtiss, Roy

2016-05-05

Based on our improved novel Salmonella vaccine delivery platform, we optimized the recombinant attenuated Salmonella typhimurium vaccine (RASV) χ12094 to deliver multiple Yersinia pestis antigens. These included LcrV196 (amino acids, 131-326), Psn encoded on pYA5383 and F1 encoded in the chromosome, their synthesis did not cause adverse effects on bacterial growth. Oral immunization with χ12094(pYA5383) simultaneously stimulated high antibody titers to LcrV, Psn and F1 in mice and presented complete protection against both subcutaneous (s.c.) and intranasal (i.n.) challenges with high lethal doses of Y. pestis CO92. Moreover, no deaths or other disease symptoms were observed in SCID mice orally immunized with χ12094(pYA5383) over a 60-day period. Therefore, the trivalent S. typhimurium-based live vaccine shows promise for a next-generation plague vaccine. Copyright © 2016 Elsevier Ltd. All rights reserved.

Immunology, epidemiology and mathematical modelling towards a better understanding of invasive non-typhoidal Salmonella disease and rational vaccination approaches.

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Mastroeni, Pietro; Rossi, Omar

2016-12-01

Invasive non-typhoidal Salmonella (iNTS) infections cause a high burden of lethal sepsis in young children and HIV patients, often associated with malaria, anaemia, malnutrition and sickle-cell disease. Vaccines against iNTS are urgently needed but none are licensed yet. Areas covered: This review illustrates how immunology, epidemiology and within-host pathogen behaviour affect invasive Salmonella infections and highlights how this knowledge can assist the improvement and choice of vaccines. Expert Commentary: Control of iNTS disease requires approaches that reduce transmission and improve diagnosis and treatment. These are often difficult to implement due to the fragile ecology and economies in endemic countries. Vaccines will be key tools in the fight against iNTS disease. To optimise vaccine design, we need to better define protective antigens and mechanisms of resistance to disease in susceptible populations even in those individuals where innate immunity may be impaired by widespread comorbidities.

Reversion to virulence evaluation of a 9R vaccine strain of Salmonella enterica serovar gallinarum in commercial brown layers

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AS Okamoto

2010-03-01

Full Text Available The live vaccine Cevac S. Gallinarum, made from a rough strain of Salmonella enterica subspecies enterica serotype Gallinarum is used for preventing fowl typhoid, a disease that still causes considerable economic losses in countries with a developing poultry industry. The objective of this paper was to evaluate a possible reversion to virulence of the strain used in a vaccine in commercial brown layers. Only Salmonella-free chicks were utilized. One hundred twenty (120 12-day-old Dekalb brown layers divided in two trials were used. The first trial had six groups of 15 birds each. Birds of group 1 were vaccinated with 10 doses of Cevac S. Gallinarum subcutaneously and 10 doses orally, in a total of 20 doses of vaccine. Then the birds of groups 2, 3, 4, and 5 received inocula that contained feces and a pool of organs with fragments of liver, heart, spleen, and cecal tonsils obtained from the immediately previous group. The second trial had three groups with 10 birds each. Birds in group 7 received inocula containing a pool of organs from birds of group 5 from trial 1, whilst the birds in group 8 were vaccinated subcutaneously with one dose of vaccine. Both trials included negative control groups (6 and 9. Throughout the experimental period, birds were monitored for reactions to the vaccination on the site of administration, clinical signs, and post-mortem lesions. In each passage, in addition to the birds euthanized to provide the inocula material, two birds from each group were euthanized for assessment of possible lesions, and their organs (liver, heart, spleen and cecal tonsils were cultured in an attempt to isolate the vaccine strain. Except for one bird from group 1, that had a local reaction on the site of vaccination - a small vesicle with less that 0.5 mm that persisted until the third day post vaccination -, no other bird had any local reaction to the vaccine or any visible clinical alteration. Birds in group 8 did not present any

Immunogenicity of a Live Recombinant Salmonella enterica Serovar Typhimurium Vaccine Expressing pspA in Neonates and Infant Mice Born from Naïve and Immunized Mothers▿ †

OpenAIRE

Shi, Huoying; Wang, Shifeng; Roland, Kenneth L.; Gunn, Bronwyn M.; Curtiss, Roy

2010-01-01

We are developing a Salmonella vectored vaccine to prevent infant pneumonia and other diseases caused by Streptococcus pneumoniae. One prerequisite for achieving this goal is to construct and evaluate new recombinant attenuated Salmonella vaccine (RASV) strains suitable for use in neonates and infants. Salmonella enterica serovar Typhimurium strain χ9558(pYA4088) specifies delivery of the pneumococcal protective antigen PspA and can protect adult mice from challenge with S. pneumoniae. This s...

Engineering and preclinical evaluation of attenuated nontyphoidal Salmonella strains serving as live oral vaccines and as reagent strains.

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Tennant, Sharon M; Wang, Jin-Yuan; Galen, James E; Simon, Raphael; Pasetti, Marcela F; Gat, Orit; Levine, Myron M

2011-10-01

While nontyphoidal Salmonella (NTS) has long been recognized as a cause of self-limited gastroenteritis, it is becoming increasingly evident that multiple-antibiotic-resistant strains are also emerging as important causes of invasive bacteremia and focal infections, resulting in hospitalizations and deaths. We have constructed attenuated Salmonella enterica serovar Typhimurium and Salmonella enterica serovar Enteritidis strains that can serve as live oral vaccines and as "reagent strains" for subunit vaccine production in a safe and economical manner. Prototype attenuated vaccine strains CVD 1921 and CVD 1941, derived from the invasive wild-type strains S. Typhimurium I77 and S. Enteritidis R11, respectively, were constructed by deleting guaBA, encoding guanine biosynthesis, and clpP, encoding a master protease regulator. The clpP mutation resulted in a hyperflagellation phenotype. An additional deletion in fliD yielded reagent strains CVD 1923 and CVD 1943, respectively, which export flagellin monomers. Oral 50% lethal dose (LD₅₀) analyses showed that the NTS vaccine strains were all highly attenuated in mice. Oral immunization with CVD 1921 or CVD 1923 protected mice against lethal challenge with wild-type S. Typhimurium I77. Immunization with CVD 1941 but not CVD 1943 protected mice against lethal infection with S. Enteritidis R11. Immune responses induced by these strains included high levels of serum IgG anti-lipopolysaccharide (LPS) and anti-flagellum antibodies, with titers increasing progressively during the immunization schedule. Since S. Typhimurium and S. Enteritidis are the most common NTS serovars associated with invasive disease, these findings can pave the way for development of a highly effective, broad-spectrum vaccine against invasive NTS.

Safety and tolerability of a live oral Salmonella typhimurium vaccine candidate in SIV-infected nonhuman primates.

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Ault, Alida; Tennant, Sharon M; Gorres, J Patrick; Eckhaus, Michael; Sandler, Netanya G; Roque, Annelys; Livio, Sofie; Bao, Saran; Foulds, Kathryn E; Kao, Shing-Fen; Roederer, Mario; Schmidlein, Patrick; Boyd, Mary Adetinuke; Pasetti, Marcela F; Douek, Daniel C; Estes, Jacob D; Nabel, Gary J; Levine, Myron M; Rao, Srinivas S

2013-12-02

Nontyphoidal Salmonella (NTS) serovars are a common cause of acute food-borne gastroenteritis worldwide and can cause invasive systemic disease in young infants, the elderly, and immunocompromised hosts, accompanied by high case fatality. Vaccination against invasive NTS disease is warranted where the disease incidence and mortality are high and multidrug resistance is prevalent, as in sub-Saharan Africa. Live-attenuated vaccines that mimic natural infection constitute one strategy to elicit protection. However, they must particularly be shown to be adequately attenuated for consideration of immunocompromised subjects. Accordingly, we examined the safety and tolerability of an oral live attenuated Salmonella typhimurium vaccine candidate, CVD 1921, in an established chronic simian immunodeficiency virus (SIV)-infected rhesus macaque model. We evaluated clinical parameters, histopathology, and measured differences in mucosal permeability to wild-type and vaccine strains. Compared to the wild-type S. typhimurium strain I77 in both SIV-infected and SIV-uninfected nonhuman primate hosts, this live-attenuated vaccine shows reduced shedding and systemic spread, exhibits limited pathological disease manifestations in the digestive tract, and induces low levels of cellular infiltration in tissues. Furthermore, wild-type S. typhimurium induces increased intestinal epithelial damage and permeability, with infiltration of neutrophils and macrophages in both SIV-infected and SIV-uninfected nonhuman primates compared to the vaccine strain. Based on shedding, systemic spread, and histopathology, the live-attenuated S. typhimurium strain CVD 1921 appears to be safe and well-tolerated in the nonhuman primate model, including chronically SIV-infected rhesus macaques. Copyright © 2013. Published by Elsevier Ltd.

[Immunogenicity of attenuated Salmonella choleraesuis vaccine strain expressing immunogenic genes of Mycoplasma hyopneumoniae in mice].

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Ma, Fengying; Zou, Haoyong; He, Qigai

2011-09-01

The study was carried out to construct and characterize Salmonella choleraesuis vaccine strain expressing immunogenic genes of Mycoplasma hyopneumoniae and to test its immunogenicity in mice. We made p36, p46, p65 and p97R1-Nrdf, the main immunogenic genes of Mycoplasma hyopneumoniae, to insert into the prokaryotic expression plasmid pYA3493. Then these recombinant plasmids and pYA3493 were electroporated into C500 asd-mutant, resulting in the recombinant Salmonella choleraesuis vaccine strains C36 (pYA-36), C46 (pYA-46), C65 (pYA-65), C97R1-Nrdf(pYA-97R1-Nrdf) and CpYA(pYA3493). We characterized these recombinant Salmonella choleraesuis vaccine strains and tested the immunogenicity in mice by intramuscular injection or orally immunized. The results of the immunogenicity in mice indicated that the group orally immunized with C36, C46, C65, C97R1-Nrdf showed significantly higher Mycoplasma pneumoniae antibody than both the group orally immunized with C36, C46, C65 and the group intramuscular injected with the Mycoplasma hyopneumoniae bacterin (M + PAC) (P Mycoplasma hyopneumoniae bacterin (M + PAC) (P 0.05). The highest level of IL-4 was found in the group orally immunized with C36, C46, C65; higher levels of IL-4 was observed in the group orally immunized with C36, C46, C65, C97R1-Nrdf than the group injected with the Mycoplasma hyopneumoniae bacterin (M + PAC); and the lowest IL-4 level was found in the group injected with C36, C46, C65. There were no significant differences among them (P > 0.05). The Mycoplasma pneumoniae antibody, IFN-gamma or IL-4 production of the each group was obviously higher than the control group (P Mycoplasma hyopneumoniae which has immunogenicity in mice especially by intramuscular injection could probably serve as a vaccine against mycoplasmal pneumonia of swine.

Use of Attenuated but Metabolically Competent Salmonella as a Probiotic To Prevent or Treat Salmonella Infection

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Sabag-Daigle, Anice; Blunk, Henry M.; Gonzalez, Juan F.; Steidley, Brandi L.; Boyaka, Prosper N.

2016-01-01

Salmonella enterica is among the most burdensome of foodborne disease agents. There are over 2,600 serovars that cause a range of disease manifestations ranging from enterocolitis to typhoid fever. While there are two vaccines in use in humans to protect against typhoid fever, there are none that prevent enterocolitis. If vaccines preventing enterocolitis were to be developed, they would likely protect against only one or a few serovars. In this report, we tested the hypothesis that probiotic organisms could compete for the preferred nutrient sources of Salmonella and thus prevent or treat infection. To this end, we added the fra locus, which encodes a utilization pathway for the Salmonella-specific nutrient source fructose-asparagine (F-Asn), to the probiotic bacterium Escherichia coli Nissle 1917 (Nissle) to increase its ability to compete with Salmonella in mouse models. We also tested a metabolically competent, but avirulent, Salmonella enterica serovar Typhimurium mutant for its ability to compete with wild-type Salmonella. The modified Nissle strain became more virulent and less able to protect against Salmonella in some instances. On the other hand, the modified Salmonella strain was safe and effective in preventing infection with wild-type Salmonella. While we tested for efficacy only against Salmonella Typhimurium, the modified Salmonella strain may be able to compete metabolically with most, if not all, Salmonella serovars, representing a novel approach to control of this pathogen. PMID:27185789

Optimization of inactivated H5N9 highly pathogenic avian influenza vaccine and inactivated Salmonella enterica serovar Typhimurium vaccine with antigen dose and prime-boost regimen in domestic ducks.

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Yuk, Seong-Su; To, Eredene-Ochir; Kwon, Jung-Hoon; Noh, Jin-Yong; Hong, Woo-Tack; Jeong, Jei-Hyun; Gwon, Gyeong-Bin; Song, Chang-Seon

2017-09-01

Owing to the increase in the number of diseases affecting ducks and the demand for food safety by consumers, vaccination has become one of the factors that influence duck meat productivity. The highly pathogenic avian influenza (HPAI) virus is one of the most prevalent and causes one of the most lethal diseases in domestic ducks, and Salmonella enterica serovar Typhimurium is a food-borne pathogen persistent in the domestic duck population. To better understand the optimal usage of HPAI and S. enterica serovar Typhimurium vaccines, we aimed to determine antigen dose, oil and gel adjuvant usage with prime-boost regimen, and vaccination age, inducing the best immune response in ducks, without an effect on body weight gain. In the case of the inactivated H5N9 vaccine, a single dose of vaccine was inadequate to induce proper antibody titer when administered to day-old ducks, which necessitates boost vaccination. Administration of the oil-adjuvanted H5N9 vaccine administration in day-old and 2-week-old ducks resulted in a lower body weight at the time of slaughtering, compared to that of gel-adjuvanted H5N9 vaccine. However, gel-adjuvanted H5N9 vaccine failed to induce proper immune response to an extent recommend by OIE-World Organization for Animal Health. In the case of the Salmonella enterica serovar Typhimurium vaccine, a moderate or low dose of vaccine was appropriate for day-old ducks receiving the gel prime-oil boost vaccination. Single vaccination with oil adjuvants affects the mean body weight of 7-week-old ducks, suggesting that the gel adjuvant is more suitable for meat production. We expect that the use of adjuvants in a prime-boost regimen and at antigen doses set in this study will be helpful to maximize body weight in the case of domestic duck production at the actual farm site. © 2017 Poultry Science Association Inc.

76 FR 41186 - Salmonella Verification Sampling Program: Response to Comments on New Agency Policies and...

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2011-07-13

... Service [Docket No. FSIS-2008-0008] Salmonella Verification Sampling Program: Response to Comments on New Agency Policies and Clarification of Timeline for the Salmonella Initiative Program (SIP) AGENCY: Food... Federal Register notice (73 FR 4767- 4774), which described upcoming policy changes in the FSIS Salmonella...

Salmonella enterica serovar Typhimurium lacking hfq gene confers protective immunity against murine typhoid.

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Uday Shankar Allam

Full Text Available Salmonella enterica is an important enteric pathogen and its various serovars are involved in causing both systemic and intestinal diseases in humans and domestic animals. The emergence of multidrug-resistant strains of Salmonella leading to increased morbidity and mortality has further complicated its management. Live attenuated vaccines have been proven superior over killed or subunit vaccines due to their ability to induce protective immunity. Of the various strategies used for the generation of live attenuated vaccine strains, focus has gradually shifted towards manipulation of virulence regulator genes. Hfq is a RNA chaperon which mediates the binding of small RNAs to the mRNA and assists in post-transcriptional gene regulation in bacteria. In this study, we evaluated the efficacy of the Salmonella Typhimurium Δhfq strain as a candidate for live oral vaccine in murine model of typhoid fever. Salmonella hfq deletion mutant is highly attenuated in cell culture and animal model implying a significant role of Hfq in bacterial virulence. Oral immunization with the Salmonella hfq deletion mutant efficiently protects mice against subsequent oral challenge with virulent strain of Salmonella Typhimurium. Moreover, protection was induced upon both multiple as well as single dose of immunizations. The vaccine strain appears to be safe for use in pregnant mice and the protection is mediated by the increase in the number of CD4(+ T lymphocytes upon vaccination. The levels of serum IgG and secretory-IgA in intestinal washes specific to lipopolysaccharide and outer membrane protein were significantly increased upon vaccination. Furthermore, hfq deletion mutant showed enhanced antigen presentation by dendritic cells compared to the wild type strain. Taken together, the studies in murine immunization model suggest that the Salmonella hfq deletion mutant can be a novel live oral vaccine candidate.

DHEC: Vaccinations

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Data, Maps - SC Public Health Diseases and Conditions Flu Tuberculosis STD/HIV and Viral Hepatitis Zika Illnesses E. coli Listeriosis Salmonella Hepatitis A Shellfish Monitoring and Regulation Certified Shippers Vaccines Teen and Preteen Vaccines Vaccines Needed for School Admission Related Topics Perinatal Hepatitis

Resistance to antimicrobials drugs and control measures of Salmonella spp in the poultry industry

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Velhner Maja

2013-01-01

Full Text Available The worldwide prevalence of multiple resistant Salmonella spp is described. Clonally distributed Salmonella Enteritidis PT4 and Salmonella Typhimurium DT104 are among the most pathogenic strains for humans. Recently there have been reports on the prevalence of ST “like” monophasic 4(5,12:i strains in some countries. Vaccination strategy and antimicorbial agent therapy is also briefly discussed. Products of animal origin must be safe and without the risk of antimicrobial resistance. Subsequently, the good management practice at farm level and HACCP in feed factories are required to cope with salmonella infections. Poultry producers in developed countries have been motivated to participate in salmonella control programs, because of public awareness on safe food and risks in the food chain. Export of poultry and poultry products is more successful in the regions where Salmonella Enteritidis and Salmonella Typhimurium have been eradicated. [Projekat Ministarstva nauke Republike Srbije, br. TR31071

Vaccines for viral and bacterial pathogens causing acute gastroenteritis: Part II: Vaccines for Shigella, Salmonella, enterotoxigenic E. coli (ETEC) enterohemorragic E. coli (EHEC) and Campylobacter jejuni

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O’Ryan, Miguel; Vidal, Roberto; del Canto, Felipe; Carlos Salazar, Juan; Montero, David

2015-01-01

In Part II we discuss the following bacterial pathogens: Shigella, Salmonella (non-typhoidal), diarrheogenic E. coli (enterotoxigenic and enterohemorragic) and Campylobacter jejuni. In contrast to the enteric viruses and Vibrio cholerae discussed in Part I of this series, for the bacterial pathogens described here there is only one licensed vaccine, developed primarily for Vibrio cholerae and which provides moderate protection against enterotoxigenic E. coli (ETEC) (Dukoral®), as well as a few additional candidates in advanced stages of development for ETEC and one candidate for Shigella spp. Numerous vaccine candidates in earlier stages of development are discussed. PMID:25715096

Regulated programmed lysis of recombinant Salmonella in host tissues to release protective antigens and confer biological containment.

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Kong, Wei; Wanda, Soo-Young; Zhang, Xin; Bollen, Wendy; Tinge, Steven A; Roland, Kenneth L; Curtiss, Roy

2008-07-08

We have devised and constructed a biological containment system designed to cause programmed bacterial cell lysis with no survivors. We have validated this system, using Salmonella enterica serovar Typhimurium vaccines for antigen delivery after colonization of host lymphoid tissues. The system is composed of two parts. The first component is Salmonella typhimurium strain chi8937, with deletions of asdA and arabinose-regulated expression of murA, two genes required for peptidoglycan synthesis and additional mutations to enhance complete lysis and antigen delivery. The second component is plasmid pYA3681, which encodes arabinose-regulated murA and asdA expression and C2-regulated synthesis of antisense asdA and murA mRNA transcribed from the P22 P(R) promoter. An arabinose-regulated c2 gene is present in the chromosome. chi8937(pYA3681) exhibits arabinose-dependent growth. Upon invasion of host tissues, an arabinose-free environment, transcription of asdA, murA, and c2 ceases, and concentrations of their gene products decrease because of cell division. The drop in C2 concentration results in activation of P(R), driving synthesis of antisense mRNA to block translation of any residual asdA and murA mRNA. A highly antigenic alpha-helical domain of Streptococcus pneumoniae Rx1 PspA was cloned into pYA3681, resulting in pYA3685 to test antigen delivery. Mice orally immunized with chi8937(pYA3685) developed antibody responses to PspA and Salmonella outer membrane proteins. No viable vaccine strain cells were detected in host tissues after 21 days. This system has potential applications with other Gram-negative bacteria in which biological containment would be desirable.

Independent bottlenecks characterize colonization of systemic compartments and gut lymphoid tissue by salmonella.

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Lim, Chee Han; Voedisch, Sabrina; Wahl, Benjamin; Rouf, Syed Fazle; Geffers, Robert; Rhen, Mikael; Pabst, Oliver

2014-07-01

Vaccination represents an important instrument to control typhoid fever in humans and protects mice from lethal infection with mouse pathogenic serovars of Salmonella species. Mixed infections with tagged Salmonella can be used in combination with probabilistic models to describe the dynamics of the infection process. Here we used mixed oral infections with tagged Salmonella strains to identify bottlenecks in the infection process in naïve and vaccinated mice. We established a next generation sequencing based method to characterize the composition of tagged Salmonella strains which offers a fast and reliable method to characterise the composition of genome-tagged Salmonella strains. We show that initial colonization of Salmonella was distinguished by a non-Darwinian selection of few bacteria setting up the infection independently in gut associated lymphoid tissue and systemic compartments. Colonization of Peyer's patches fuels the sustained spread of bacteria into mesenteric lymph nodes via dendritic cells. In contrast, infection of liver and spleen originated from an independent pool of bacteria. Vaccination only moderately reduced invasion of Peyer's patches but potently uncoupled bacterial populations present in different systemic compartments. Our data indicate that vaccination differentially skews the capacity of Salmonella to colonize systemic and gut immune compartments and provide a framework for the further dissection of infection dynamics.

Independent bottlenecks characterize colonization of systemic compartments and gut lymphoid tissue by salmonella.

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Chee Han Lim

2014-07-01

Full Text Available Vaccination represents an important instrument to control typhoid fever in humans and protects mice from lethal infection with mouse pathogenic serovars of Salmonella species. Mixed infections with tagged Salmonella can be used in combination with probabilistic models to describe the dynamics of the infection process. Here we used mixed oral infections with tagged Salmonella strains to identify bottlenecks in the infection process in naïve and vaccinated mice. We established a next generation sequencing based method to characterize the composition of tagged Salmonella strains which offers a fast and reliable method to characterise the composition of genome-tagged Salmonella strains. We show that initial colonization of Salmonella was distinguished by a non-Darwinian selection of few bacteria setting up the infection independently in gut associated lymphoid tissue and systemic compartments. Colonization of Peyer's patches fuels the sustained spread of bacteria into mesenteric lymph nodes via dendritic cells. In contrast, infection of liver and spleen originated from an independent pool of bacteria. Vaccination only moderately reduced invasion of Peyer's patches but potently uncoupled bacterial populations present in different systemic compartments. Our data indicate that vaccination differentially skews the capacity of Salmonella to colonize systemic and gut immune compartments and provide a framework for the further dissection of infection dynamics.

Brucella lipopolysaccharide reinforced Salmonella delivering Brucella immunogens protects mice against virulent challenge.

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Lalsiamthara, Jonathan; Lee, John Hwa

2017-06-01

Intracellular pathogen Salmonella exhibits natural infection broadly analogous to Brucella, this phenomenon makes Salmonella a pragmatic choice for an anti-Brucella vaccine delivery platform. In this study we developed and formulated a combination of four attenuated Salmonella Typhimurium live vector strains delivering heterologous Brucella antigens (rBs), namely lumazine synthase, proline racemase subunit A, lipoprotein outer membrane protein-19, and Cu-Zn superoxide dismutase. With an aim to develop a cross-protecting vaccine, Brucella pan-species conserved rBs were selected. The present study compared the efficacy of smooth and rough variants of Salmonella delivery vector and also evaluated the inclusion of purified Brucella lipopolysaccharide (LPS) in the formulation. Immunization of SPF-BALB/c mice with the vaccine combinations significantly (P≤0.05) reduced splenic wild-type Brucella abortus 544 colonization as compared to non-immunized mice as well as Salmonella only immunized mice. Increased induction of Brucella specific-IgG, sIgA production, and antigen-specific splenocyte proliferative responses were observed in the mice immunized with the formulations as compared to naïve or vector only immunized mice. Modulatory effects of rB and LPS on production of interleukin (IL)-4, IL-12, and interferon-γ were detected in splenocytes of mice immunized with the formulation. Rough Salmonella variant in combination with LPS could further enhance the efficacy of the delivery when applied intraperitoneally. Taken together, it is compelling that Brucella LPS-augmented Salmonella vector delivering immunogenic Brucella proteins may be more suitable than the current non-ideal live Brucella abortus vaccine. The vaccine system also provides a basis for the development of cross-protecting vaccine capable of preventing multispecies brucellosis. Copyright © 2017 Elsevier B.V. All rights reserved.

Whole Genome Sequence Analysis of Salmonella Typhi Isolated in Thailand before and after the Introduction of a National Immunization Program.

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Zoe A Dyson

2017-01-01

Full Text Available Vaccines against Salmonella Typhi, the causative agent of typhoid fever, are commonly used by travellers, however, there are few examples of national immunization programs in endemic areas. There is therefore a paucity of data on the impact of typhoid immunization programs on localised populations of S. Typhi. Here we have used whole genome sequencing (WGS to characterise 44 historical bacterial isolates collected before and after a national typhoid immunization program that was implemented in Thailand in 1977 in response to a large outbreak; the program was highly effective in reducing typhoid case numbers. Thai isolates were highly diverse, including 10 distinct phylogenetic lineages or genotypes. Novel prophage and plasmids were also detected, including examples that were previously only reported in Shigella sonnei and Escherichia coli. The majority of S. Typhi genotypes observed prior to the immunization program were not observed following it. Post-vaccine era isolates were more closely related to S. Typhi isolated from neighbouring countries than to earlier Thai isolates, providing no evidence for the local persistence of endemic S. Typhi following the national immunization program. Rather, later cases of typhoid appeared to be caused by the occasional importation of common genotypes from neighbouring Vietnam, Laos, and Cambodia. These data show the value of WGS in understanding the impacts of vaccination on pathogen populations and provide support for the proposal that large-scale typhoid immunization programs in endemic areas could result in lasting local disease elimination, although larger prospective studies are needed to test this directly.

the developme ... ta .. \\~ production of typhoid fever vaccines toxicity ...

African Journals Online (AJOL)

BSN

Sixty-six different types of ~"?hoid vaccines were prepared using three adjuvants and using both local and imported suams of Salmonella typhi and Salmonella paratyphi A, B, C. About 3,960 mice were used at the ;a:.e of 60 mice per vaccine. The mice were vaccinated intraperitonially with 0.5m1 of sen.le batch of vaccines.

Evaluation of the protective efficacy of Salmonella Gallinarum 9R ...

African Journals Online (AJOL)

Evaluation of the protective efficacy of Salmonella Gallinarum 9R strain vaccine against Salmonella strains isolated from cases suspected of salmonellosis outbreaks in poultry farms in central Ethiopia.

Salmonella and Eggs: From Production to Plate

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Whiley, Harriet; Ross, Kirstin

2015-01-01

Salmonella contamination of eggs and egg shells has been identified as a public health concern worldwide. A recent shift in consumer preferences has impacted on the egg industry, with a push for cage-free egg production methods. There has also been an increased desire from consumers for raw and unprocessed foods, potentially increasing the risk of salmonellosis. In response to these changes, this review explores the current literature regarding Salmonella contamination of eggs during the production processing through to food handling protocols. The contamination of eggs with Salmonella during the production process is a complex issue, influenced by many variables including flock size, flock age, stress, feed, vaccination, and cleaning routines. Currently there is no consensus regarding the impact of caged, barn and free range egg production has on Salmonella contamination of eggs. The literature regarding the management and control strategies post-collection, during storage, transport and food handling is also reviewed. Pasteurisation and irradiation were identified as the only certain methods for controlling Salmonella and are essential for the protection of high risk groups, whereas control of temperature and pH were identified as potential control methods to minimise the risk for foods containing raw eggs; however, further research is required to provide more detailed control protocols and education programs to reduce the risk of salmonellosis from egg consumption. PMID:25730295

Salmonella and Eggs: From Production to Plate

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Harriet Whiley

2015-02-01

Full Text Available Salmonella contamination of eggs and egg shells has been identified as a public health concern worldwide. A recent shift in consumer preferences has impacted on the egg industry, with a push for cage-free egg production methods. There has also been an increased desire from consumers for raw and unprocessed foods, potentially increasing the risk of salmonellosis. In response to these changes, this review explores the current literature regarding Salmonella contamination of eggs during the production processing through to food handling protocols. The contamination of eggs with Salmonella during the production process is a complex issue, influenced by many variables including flock size, flock age, stress, feed, vaccination, and cleaning routines. Currently there is no consensus regarding the impact of caged, barn and free range egg production has on Salmonella contamination of eggs. The literature regarding the management and control strategies post-collection, during storage, transport and food handling is also reviewed. Pasteurisation and irradiation were identified as the only certain methods for controlling Salmonella and are essential for the protection of high risk groups, whereas control of temperature and pH were identified as potential control methods to minimise the risk for foods containing raw eggs; however, further research is required to provide more detailed control protocols and education programs to reduce the risk of salmonellosis from egg consumption.

Salmonella and eggs: from production to plate.

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Whiley, Harriet; Ross, Kirstin

2015-02-26

Salmonella contamination of eggs and egg shells has been identified as a public health concern worldwide. A recent shift in consumer preferences has impacted on the egg industry, with a push for cage-free egg production methods. There has also been an increased desire from consumers for raw and unprocessed foods, potentially increasing the risk of salmonellosis. In response to these changes, this review explores the current literature regarding Salmonella contamination of eggs during the production processing through to food handling protocols. The contamination of eggs with Salmonella during the production process is a complex issue, influenced by many variables including flock size, flock age, stress, feed, vaccination, and cleaning routines. Currently there is no consensus regarding the impact of caged, barn and free range egg production has on Salmonella contamination of eggs. The literature regarding the management and control strategies post-collection, during storage, transport and food handling is also reviewed. Pasteurisation and irradiation were identified as the only certain methods for controlling Salmonella and are essential for the protection of high risk groups, whereas control of temperature and pH were identified as potential control methods to minimise the risk for foods containing raw eggs; however, further research is required to provide more detailed control protocols and education programs to reduce the risk of salmonellosis from egg consumption.

An oral Salmonella-based vaccine inhibits liver metastases by promoting tumor-specific T cell-mediated immunity in celiac & portal lymph nodes. A preclinical study.

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Alejandrina eVendrell

2016-03-01

Full Text Available Primary tumor excision is one of the therapies of cancer most widely used. However, the risk of metastases development still exists following tumor resection. The liver is a common site of metastatic disease for numerous cancers. Breast cancer is one of the most frequent source of metastases to the liver. The aim of this work was to evaluate the efficacy of the orally-administered Salmonella Typhi vaccine strain CVD 915 on the development of liver metastases in a mouse model of breast cancer. To this end, one group of BALB/c mice was immunized with CVD 915 via o.g. while another received PBS as a control. After 24 h, mice were injected with LM3 mammary adenocarcinoma cells into the spleen and subjected to splenectomy. This oral Salmonella-based vaccine produced an antitumor effect, leading to a decrease in the number and volume of liver metastases. Immunization with Salmonella induced an early cellular immune response in mice. This innate stimulation rendered a large production of IFN-γ by intrahepatic immune cells (IHIC detected within 24 h. An antitumor adaptive immunity was found in the liver and celiac & portal lymph nodes (LDLN 21 days after oral bacterial inoculation. The antitumor immune response inside the liver was associated with increased CD4+ and DC cell populations as well as with an inflammatory infiltrate located around liver metastatic nodules. Enlarged levels of inflammatory cytokines (IFN-γ and TNF were also detected in IHIC. Furthermore, a tumor-specific production of IFN-γ and TNF as well as tumor-specific IFN-γ-producing CD8 T cells (CD8+IFN-γ+ were found in the celiac & portal lymph nodes of Salmonella-treated mice. This study provides first evidence for the involvement of LDLN in the development of an efficient cellular immune response against hepatic tumors, which resulted in the elimination of liver metastases after oral Salmonella-based vaccination.

A longitudinal study of Salmonella from snakes used in a public outreach program.

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Goupil, Brad A; Trent, Ava M; Bender, Jeff; Olsen, Karen E; Morningstar, Brenda R; Wünschmann, Arno

2012-12-01

Snakes are considered to be a source of Salmonella infection for humans, but little is known about the actual serotype prevalence in healthy snakes over time. Twelve snakes involved in a public outreach program, representing seven different species, were tested weekly for shedding of Salmonella sp. over a period of 10 consecutive weeks. The snakes were housed in close proximity but in separate exhibits. Fresh fecal samples (when available) or cloacal swabs were cultured for Salmonella sp., and subsequent Salmonella isolates were serotyped. As representatives of the feed source, the feces of two mice and the intestines of one rat were cultured weekly. Fecal samples from 11 of the 12 snakes were positive for Salmonella at least once. Seven (58%) of 12 snakes were culture positive five times or more. The weekly prevalence of Salmonella shedding varied between 25% and 66%. Two or more different serotypes were isolated from nine snakes over time; however, a predominant serotype was generally isolated from each of these snakes. Altogether 15 different serotypes were identified. Serotypes of public health concern included Newport, Oranienburg, and Muenchen. Two samples from feeder rodents were positive for Salmonella. The results are consistent with previous studies showing high intestinal colonization rates with Salmonella sp. in snakes. Frequent and intermittent shedding of multiple serotypes was evident. Feeder rodents might serve as a source for intestinal colonization. Appropriate handling protocols should be implemented for all reptiles associated with public outreach programs to minimize risk of Salmonella transmission to the public.

Attenuated Salmonella enterica Serovar Typhi and Shigella flexneri 2a Strains Mucosally Deliver DNA Vaccines Encoding Measles Virus Hemagglutinin, Inducing Specific Immune Responses and Protection in Cotton Rats

OpenAIRE

Pasetti, Marcela F.; Barry, Eileen M.; Losonsky, Genevieve; Singh, Mahender; Medina-Moreno, Sandra M.; Polo, John M.; Ulmer, Jeffrey; Robinson, Harriet; Sztein, Marcelo B.; Levine, Myron M.

2003-01-01

Measles remains a leading cause of child mortality in developing countries. Residual maternal measles antibodies and immunologic immaturity dampen immunogenicity of the current vaccine in young infants. Because cotton rat respiratory tract is susceptible to measles virus (MV) replication after intranasal (i.n.) challenge, this model can be used to assess the efficacy of MV vaccines. Pursuing a new measles vaccine strategy that might be effective in young infants, we used attenuated Salmonella...

[Salmonella in pig farms. Limitations of counselling and alternatives to the exclusive control of slaughter pigs].

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Rostalski, A

2015-01-01

The goal of reducing salmonella prevalence in slaughter pigs using a monitoring system is difficult to realize. Many of the category-III-farms have proper hygiene and clinical signs are often lacking, which makes the implementation of sustainable counselling concepts difficult. The improvement of biological performances and the changes in sow keeping and feeding concepts lays the focus on the breeding and farrowing units. Information on the salmonella status of the delivering pig farms is essential for establishing, for example, vaccination programs. A general inspection duty for all pig-producing units beginning with the breeding herds is reasonable. To achieve this, measurements for stress reduction, changes of the current detection systems and early information of farms with an acute salmonella problem are discussed.

Overcoming barriers in HPV vaccination and screening programs

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Alex Vorsters

2017-12-01

Full Text Available The Human Papillomavirus Prevention and Control Board brought together experts to discuss optimizing HPV vaccination and screening programs.Board members reviewed the safety profile of licensed HPV vaccines based on clinical and post-marketing data, reaching a consensus that current safety data is reassuring.Successful vaccination programs used well-coordinated communication campaigns, integrating (social media to spread awareness. Communication of evidence supporting vaccine effectiveness had beneficial effects on the perception of the vaccine. However, anti-vaccination campaigns have threatened existing programs in many countries.Measurement and monitoring of HPV vaccine confidence over time could help understand the nature and scale of waning confidence, define issues and intervene appropriately using context-specific evidence-based strategies. Finally, a broad group of stakeholders, such as teachers, health care providers and the media should also be provided with accurate information and training to help support prevention efforts through enhanced understanding of the risks and benefits of vaccination.Similarly, while cervical cancer screening through population-based programs is highly effective, barriers to screening exist: awareness in countries with population-based screening programs, access for vulnerable populations, and access and affordability in low- and middle-income countries. Integration of primary and secondary prevention has the potential to accelerate the decrease in cervical cancer incidence. Keywords: (max 6 Human papillomavirus, Vaccine, Screening, Barriers, Vaccine confidence

Preexisting Salmonella-specific immunity interferes with the subsequent development of immune responses against the Salmonella strains delivering H9N2 hemagglutinin.

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Hajam, Irshad Ahmed; Lee, John Hwa

2017-06-01

Recombinant Salmonella strains expressing foreign heterologous antigens have been extensively studied as promising live vaccine delivery vehicles. In this study, we constructed attenuated smooth (S-HA) and rough (R-HA) Salmonella strains expressing hemagglutinin (HA) of H9N2, a low pathogenic avian influenza A virus. We then investigated the HA-specific immune responses following oral immunization with either S-HA or R-HA strain in chicken model. We further examined the effects of the preexisting anti-Salmonella immunity on the subsequent elicitation of the HA and the Salmonella ompA specific immune responses. Our results showed that primary immunization with either the S-HA or the R-HA strain elicited comparable HA-specific immune responses and the responses were significantly (pSalmonella vector control. When chickens were pre-immunized with the smooth Salmonella carrier alone and then vaccinated with either S-HA or R-HA strain 3, 6 and 9 weeks later, respectively, significant reductions were seen for HA-specific immune responses at week 6, a point which corresponded to the peak of the primary Salmonella-specific antibody responses. No reductions were seen at week 3 and 9, albeit, the HA-specific immune responses were boosted at week 9, a point which corresponded to the lowest primary Salmonella-specific antibody responses. The ompA recall responses remain refractory at week 3 and 6 following deliberate immunization with the carrier strain, but were significantly (pSalmonella immunity inhibits antigen-specific immune responses and this effect could be avoided by carefully selecting the time point when carrier-specific immune responses are relatively low. Copyright © 2017 Elsevier B.V. All rights reserved.

A Salmonella typhimurium ghost vaccine induces cytokine expression in vitro and immune responses in vivo and protects rats against homologous and heterologous challenges.

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Nagarajan Vinod

Full Text Available Salmonella enteritidis and Salmonella typhimurium are important food-borne bacterial pathogens, which are responsible for diarrhea and gastroenteritis in humans and animals. In this study, S. typhimurium bacterial ghost (STG was generated based on minimum inhibitory concentration (MIC of sodium hydroxide (NaOH. Experimental studies performed using in vitro and in vivo experimental model systems to characterize effects of STG as a vaccine candidate. When compared with murine macrophages (RAW 264.7 exposed to PBS buffer (98.1%, the macrophages exposed to formalin-killed inactivated cells (FKC, live wild-type bacterial cells and NaOH-induced STG at 1 × 108 CFU/mL showed 85.6%, 66.5% and 84.6% cell viability, respectively. It suggests that STG significantly reduces the cytotoxic effect of wild-type bacterial cells. Furthermore, STG is an excellent inducer for mRNAs of pro-inflammatory cytokine (TNF-α, IL-1β and factor (iNOS, anti-inflammatory cytokine (IL-10 and dual activities (IL-6 in the stimulated macrophage cells. In vivo, STG vaccine induced humoral and cellular immune responses and protection against homologous and heterologous challenges in rats. Furthermore, the immunogenicity and protective efficacy of STG vaccine were compared with those of FKC and non-vaccinated PBS control groups. The vaccinated rats from STG group exhibited higher levels of serum IgG antibody responses, serum bactericidal antibodies, and CD4+ and CD8+ T-cell populations than those of the FKC and PBS control groups. Most importantly, after challenge with homologous and heterologous strains, the bacterial loads in the STG group were markedly lower than the FKC and PBS control groups. In conclusion, these findings suggest that the STG vaccine induces protective immunity against homologous and heterologous challenges.

Oral vaccination with LcrV from Yersinia pestis KIM delivered by live attenuated Salmonella enterica serovar Typhimurium elicits a protective immune response against challenge with Yersinia pseudotuberculosis and Yersinia enterocolitica.

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Branger, Christine G; Torres-Escobar, Ascención; Sun, Wei; Perry, Robert; Fetherston, Jacqueline; Roland, Kenneth L; Curtiss, Roy

2009-08-27

The use of live recombinant attenuated Salmonella vaccines (RASV) synthesizing Yersinia proteins is a promising approach for controlling infection by Yersinia species. In this study, we constructed attenuated Salmonella strains which synthesize a truncated form of LcrV, LcrV196 and evaluated the immune response and protective efficacy elicited by these strains in mice against two other major species of Yersinia: Yersinia pseudotuberculosis and Yersinia enterocolitica. Surprisingly, we found that the RASV strain alone was sufficient to afford nearly full protection against challenge with Y. pseudotuberculosis, indicating the likelihood that Salmonella produces immunogenic cross-protective antigens. In contrast, lcrV196 expression was required for protection against challenge with Y. enterocolitica strain 8081, but was not sufficient to achieve significant protection against challenge with Y. enterocolitica strain WA, which expressed a divergent form of lcrV. Nevertheless, we are encouraged by these findings to continue pursuing our long-term goal of developing a single vaccine to protect against all three human pathogenic species of Yersinia.

Mucosal delivery of a transmission-blocking DNA vaccine encoding Giardia lamblia CWP2 by Salmonella typhimurium bactofection vehicle.

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Abdul-Wahid, Aws; Faubert, Gaétan

2007-12-05

In this study, we investigated the use of Salmonella typhimurium (STM1 strain) as a bactofection vehicle to deliver a transmission-blocking DNA vaccine (TBDV) plasmid to the intestinal immune system. The gene encoding the full length cyst wall protein-2 (CWP2) from Giardia lamblia was subcloned into the pCDNA3 mammalian expression vector and stably introduced into S. typhimurium STM1. Eight-week-old female BALB/c mice were orally immunized every 2 weeks, for a total of three immunizations. Vaccinated and control mice were sacrificed 1 week following the last injection. Administration of the DNA vaccine led to the production of CWP2-specific cellular immune responses characterized by a mixed Th1/Th2 response. Using ELISA, antigen-specific IgA and IgG antibodies were detected in intestinal secretions. Moreover, analysis of sera demonstrated that the DNA immunization also stimulated the production of CWP2-specific IgG antibodies that were mainly of the IgG2a isotype. Finally, challenge infection with live Giardia muris cysts revealed that mice receiving the CWP2-encoding DNA vaccine were able to reduce cyst shedding by approximately 60% compared to control mice. These results demonstrate, for the first time, the development of parasite transmission-blocking immunity at the intestinal level following the administration of a mucosal DNA vaccine delivered by S. typhimurium STM1.

Fine-tuning synthesis of Yersinia pestis LcrV from runaway-like replication balanced-lethal plasmid in a Salmonella enterica serovar typhimurium vaccine induces protection against a lethal Y. pestis challenge in mice.

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Torres-Escobar, Ascención; Juárez-Rodríguez, María Dolores; Gunn, Bronwyn M; Branger, Christine G; Tinge, Steven A; Curtiss, Roy

2010-06-01

A balanced-lethal plasmid expression system that switches from low-copy-number to runaway-like high-copy-number replication (pYA4534) was constructed for the regulated delayed in vivo synthesis of heterologous antigens by vaccine strains. This is an antibiotic resistance-free maintenance system containing the asdA gene (essential for peptidoglycan synthesis) as a selectable marker to complement the lethal chromosomal DeltaasdA allele in live recombinant attenuated Salmonella vaccines (RASVs) such as Salmonella enterica serovar Typhimurium strain chi9447. pYA4534 harbors two origins of replication, pSC101 and pUC (low and high copy numbers, respectively). The pUC replication origin is controlled by a genetic switch formed by the operator/promoter of the P22 cro gene (O/P(cro)) (P(R)), which is negatively regulated by an arabinose-inducible P22 c2 gene located on both the plasmid and the chromosome (araC P(BAD) c2). The absence of arabinose, which is unavailable in vivo, triggers replication to a high-copy-number plasmid state. To validate these vector attributes, the Yersinia pestis virulence antigen LcrV was used to develop a vaccine against plague. An lcrV sequence encoding amino acids 131 to 326 (LcrV196) was optimized for expression in Salmonella, flanked with nucleotide sequences encoding the signal peptide (SS) and the carboxy-terminal domain (CT) of beta-lactamase, and cloned into pYA4534 under the control of the P(trc) promoter to generate plasmid pYA4535. Our results indicate that the live Salmonella vaccine strain chi9447 harboring pYA4535 efficiently stimulated a mixed Th1/Th2 immune response that protected mice against lethal challenge with Y. pestis strain CO92 introduced through either the intranasal or subcutaneous route.

Fine-Tuning Synthesis of Yersinia pestis LcrV from Runaway-Like Replication Balanced-Lethal Plasmid in a Salmonella enterica Serovar Typhimurium Vaccine Induces Protection against a Lethal Y. pestis Challenge in Mice▿

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Torres-Escobar, Ascención; Juárez-Rodríguez, María Dolores; Gunn, Bronwyn M.; Branger, Christine G.; Tinge, Steven A.; Curtiss, Roy

2010-01-01

A balanced-lethal plasmid expression system that switches from low-copy-number to runaway-like high-copy-number replication (pYA4534) was constructed for the regulated delayed in vivo synthesis of heterologous antigens by vaccine strains. This is an antibiotic resistance-free maintenance system containing the asdA gene (essential for peptidoglycan synthesis) as a selectable marker to complement the lethal chromosomal ΔasdA allele in live recombinant attenuated Salmonella vaccines (RASVs) such as Salmonella enterica serovar Typhimurium strain χ9447. pYA4534 harbors two origins of replication, pSC101 and pUC (low and high copy numbers, respectively). The pUC replication origin is controlled by a genetic switch formed by the operator/promoter of the P22 cro gene (O/Pcro) (PR), which is negatively regulated by an arabinose-inducible P22 c2 gene located on both the plasmid and the chromosome (araC PBAD c2). The absence of arabinose, which is unavailable in vivo, triggers replication to a high-copy-number plasmid state. To validate these vector attributes, the Yersinia pestis virulence antigen LcrV was used to develop a vaccine against plague. An lcrV sequence encoding amino acids 131 to 326 (LcrV196) was optimized for expression in Salmonella, flanked with nucleotide sequences encoding the signal peptide (SS) and the carboxy-terminal domain (CT) of β-lactamase, and cloned into pYA4534 under the control of the Ptrc promoter to generate plasmid pYA4535. Our results indicate that the live Salmonella vaccine strain χ9447 harboring pYA4535 efficiently stimulated a mixed Th1/Th2 immune response that protected mice against lethal challenge with Y. pestis strain CO92 introduced through either the intranasal or subcutaneous route. PMID:20308296

Technologies and Approaches to Elucidate and Model the Virulence Program of Salmonella.

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McDermott, Jason E.; Yoon, Hyunjin; Nakayasu, Ernesto S.; Metz, Thomas O.; Hyduke, Daniel R.; Kidwai, Afshan S.; Palsson, Bernhard O.; Adkins, Joshua N.; Heffron, Fred

2011-04-01

Salmonella is a primary cause of enteric diseases in a variety of animals. During its evolution into a pathogenic bacterium, Salmonella acquired an elaborate regulatory network that responds to multiple environmental stimuli within host animals and integrates them resulting in fine regulation of the virulence program. The coordinated action by this regulatory network involves numerous virulence regulators, necessitating genome-wide profiling analysis to assess and combine efforts from multiple regulons. In this review we discuss recent high-throughput analytic approaches to understand the regulatory network of Salmonella that controls virulence processes. Application of high-throughput analyses have generated a large amount of data and driven development of computational approaches required for data integration. Therefore, we also cover computer-aided network analyses to infer regulatory networks, and demonstrate how genome-scale data can be used to construct regulatory and metabolic systems models of Salmonella pathogenesis. Genes that are coordinately controlled by multiple virulence regulators under infectious conditions are more likely to be important for pathogenesis. Thus, reconstructing the global regulatory network during infection or, at the very least, under conditions that mimic the host cellular environment not only provides a bird’s eye view of Salmonella survival strategy in response to hostile host environments but also serves as an efficient means to identify novel virulence factors that are essential for Salmonella to accomplish systemic infection in the host.

Evaluating human papillomavirus vaccination programs in Canada: should provincial healthcare pay for voluntary adult vaccination?

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Smith? Robert J

2008-04-01

Full Text Available Abstract Background Recently, provincial health programs in Canada and elsewhere have begun rolling out vaccination against human papillomavirus for girls aged 9–13. While vaccination is voluntary, the cost of vaccination is waived, to encourage parents to have their daughters vaccinated. Adult women who are eligible for the vaccine may still receive it, but at a cost of approximately CAN$400. Given the high efficacy and immunogenicity of the vaccine, the possibility of eradicating targeted types of the virus may be feasible, assuming the vaccination programs are undertaken strategically. Methods We develop a mathematical model to describe the epidemiology of vaccination against human papillomavirus, accounting for a widespread childhood vaccination program that may be supplemented by voluntary adult vaccination. A stability analysis is performed to determine the stability of the disease-free equilibrium. The critical vaccine efficacy and immunogenicity thresholds are derived, and the minimum level of adult vaccination required for eradication of targeted types is determined. Results We demonstrate that eradication of targeted types is indeed feasible, although the burden of coverage for a childhood-only vaccination program may be high. However, if a small, but non-negligible, proportion of eligible adults can be vaccinated, then the possibility of eradication of targeted types becomes much more favourable. We provide a threshold for eradication in general communities and illustrate the results with numerical simulations. We also investigate the effects of suboptimal efficacy and immunogenicity and show that there is a critical efficacy below which eradication of targeted types is not possible. If eradication is possible, then there is a critical immunogenicity such that even 100% childhood vaccination will not eradicate the targeted types of the virus and must be supplemented with voluntary adult vaccination. However, the level of adult

A Perspective on Invasive Salmonella Disease in Africa.

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Crump, John A; Heyderman, Robert S

2015-11-01

Salmonella enterica is a leading cause of community-acquired bloodstream infection in Africa. The contribution of typhoidal and nontyphoidal Salmonella serovars to invasive disease varies considerably in place and time, even within the same country. Nonetheless, many African countries are now thought to experience typhoid fever incidence >100 per 100,000 per year with approximately 1% of patients dying. Invasive nontyphoidal Salmonella (iNTS) disease was estimated to cause 3.4 million illnesses and 681 316 deaths in 2010, with the most disease in Africa. Antimicrobial drug resistance is a growing problem in S. enterica that threatens to further compromise patient outcomes. Reservoirs for nontyphoidal Salmonella and the predominant routes of transmission for typhoidal and nontyphoidal Salmonella are not well understood in Africa, hampering the design of evidence-based, non-vaccine- and vaccine-based prevention measures. It is difficult to distinguish clinically invasive Salmonella disease from febrile illnesses caused by other pathogens. Blood cultures are the mainstay of laboratory diagnosis, but lack sensitivity due to the low magnitude of bacteremia, do not produce results at point of care, and are not widely available in Africa. Serologic approaches to diagnosis remain inaccurate, and nucleic acid amplification tests are also compromised by low concentrations of bacteria. High-throughput whole-genome sequencing, together with a range of novel analytic pipelines, has provided new insights into the complex pattern of epidemiology, pathogenesis, and host adaptation. Concerted efforts are therefore needed to apply these new tools in the context of high-quality field surveillance to improve diagnosis, patient management, control, and prevention of invasive Salmonella infections in Africa. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Identification of protective antigens for vaccination against systemic salmonellosis

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Dirk eBumann

2014-08-01

Full Text Available There is an urgent medical need for improved vaccines with broad serovar coverage and high efficacy against systemic salmonellosis. Subunit vaccines offer excellent safety profiles but require identification of protective antigens, which remains a challenging task. Here, I review crucial properties of Salmonella antigens that might help to narrow down the number of potential candidates from more than 4000 proteins encoded in Salmonella genomes, to a more manageable number of 50-200 most promising antigens. I also discuss complementary approaches for antigen identification and potential limitations of current pre-clinical vaccine testing.

[HPV Vaccination Program - The History and Recent Progress].

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Yoshikawa, Hiroyuki

2017-09-01

Four years have passed since HPV vaccination "crisis" occurred in June 2013. In Japan,a publicly funded HPV vaccination program for adolescent females aged 12-16 years began in December 2010. However,the Japanese government withdrew its recommendation for HPV vaccination in June, 2013 because news reports on potential adverse effects of HPV vaccines without any medical evidence appeared repeatedly. The vaccination coverage among adolescent females decreased quickly from around 70%in females born between 1994 and 1999 to only 1%in females born since 2001 over the country. The suspension of recommendation for vaccination has continued to the present,though there is no scientific or epidemiologic evidence to demonstrate the causal linkage between post-vaccination symptoms and the HPV vaccines. Very recently,an ecological investigation reported that similar symptoms also occur in unvaccinated adolescents in Japan. Medical organizations in Japan are also calling for a resumption of the HPV vaccination program. Now,the resumption of the recommendation needs a political judgment.

Population Dynamics of Salmonella enterica Serotypes in Commercial Egg and Poultry Production ▿

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Foley, Steven L.; Nayak, Rajesh; Hanning, Irene B.; Johnson, Timothy J.; Han, Jing; Ricke, Steven C.

2011-01-01

Fresh and processed poultry have been frequently implicated in cases of human salmonellosis. Furthermore, increased consumption of meat and poultry has increased the potential for exposure to Salmonella enterica. While advances have been made in reducing the prevalence and frequency of Salmonella contamination in processed poultry, there is mounting pressure on commercial growers to prevent and/or eliminate these human pathogens in preharvest production facilities. Several factors contribute to Salmonella colonization in commercial poultry, including the serovar and the infectious dose. In the early 1900s, Salmonella enterica serovars Pullorum and Gallinarum caused widespread diseases in poultry, but vaccination and other voluntary programs helped eradicate pullorum disease and fowl typhoid from commercial flocks. However, the niche created by the eradication of these serovars was likely filled by S. Enteritidis, which proliferated in the bird populations. While this pathogen remains a significant problem in commercial egg and poultry production, its prevalence among poultry has been declining since the 1990s. Coinciding with the decrease of S. Enteritidis, S. Heidelberg and S. Kentucky have emerged as the predominant serovars in commercial broilers. In this review, we have highlighted bacterial genetic and host-related factors that may contribute to such shifts in Salmonella populations in commercial poultry and intervention strategies that could limit their colonization. PMID:21571882

Potential Cost-Effectiveness of an Influenza Vaccination Program Offering Microneedle Patch for Vaccine Delivery in Children.

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Carlos Wong

Full Text Available The influenza vaccine coverage rate of children is low in Hong Kong. Microneedle patches (MNPs is a technology under development for painless delivery of vaccines. This study aimed to examine the potential clinical outcomes and direct medical costs of an influenza program offering MNP vaccine to children who have declined intramuscular (IM vaccine in Hong Kong.A decision model was designed to compare potential outcomes between IM vaccine program and a program offering MNP vaccine to those declined IM vaccine (IM/MNP program in a hypothetical cohort of children over one-year time horizon. The model outcomes included direct medical cost, influenza infection rate, mortality rate, and quality-adjusted life-years (QALYs loss. Model inputs were retrieved from published literature. Sensitivity analyses were performed to examine the robustness of model results.In base-case analysis, IM/MNP program was more costly per child (USD19.13 versus USD13.69; USD1 = HKD7.8 with lower influenza infection rate (98.9 versus 124.8 per 1,000 children, hospitalization rate (0.83 versus 1.05 per 1,000 children and influenza-related mortality rate (0.00042 versus 0.00052 per 1,000 children when compared to IM program. The incremental cost per QALY saved (ICER of IM/MNP program versus IM program was 27,200 USD/QALY. Using gross domestic product (GDP per capita of Hong Kong (USD40,594 as threshold of willingness-to-pay (WTP per QALY, one-way sensitivity analysis found ICER of IM/MNP to exceed WTP when duration of illness in outpatient setting was 1.39-time of IM vaccine cost. In 10,000 Monte Carlo simulations, IM/MNP program was the preferred option in 57.28% and 91.68% of the time, using 1x and 3x GDP per capita as WTP threshold, respectively.Acceptance of IM/MNP program as the preferred program was subject to the WTP threshold, duration of illness in outpatient settings, and cost of MNP vaccine.

Oral DNA Vaccine in Chickens

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Seyed Davoud Jazayeri

2012-01-01

Full Text Available Attenuated Salmonella has been used as a carrier for DNA vaccine. However, in vitro and in vivo studies on the bacteria following transfection of plasmid DNA were poorly studied. In this paper, eukaryotic expression plasmids encoding avian influenza virus (AIV subtype H5N1 genes, pcDNA3.1/HA, NA, and NP, were transfected into an attenuated Salmonella enteric typhimurium SV4089. In vitro stability of the transfected plasmids into Salmonella were over 90% after 100 generations. The attenuated Salmonella were able to invade MCF-7 (1.2% and MCF-10A (0.5% human breast cancer cells. Newly hatched specific-pathogen-free (SPF chicks were inoculated once by oral gavage with 109 colony-forming unit (CFU of the attenuated Salmonella. No abnormal clinical signs or deaths were recorded after inoculation. Viable bacteria were detected 3 days after inoculation by plating from spleen, liver, and cecum. Fluorescent in situ hybridization (FISH and polymerase chain reaction (PCR were carried out for confirmation. Salmonella was not detected in blood cultures although serum antibody immune responses to Salmonella O antiserum group D1 factor 1, 9, and 12 antigens were observed in all the inoculated chickens after 7 days up to 35 days. Our results showed that live attenuated S. typhimurium SV4089 harboring pcDNA3.1/HA, NA, and NP may provide a unique alternative as a carrier for DNA oral vaccine in chickens.

The effects of vaccination and immunity on bacterial infection dynamics in vivo.

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Chris Coward

2014-09-01

Full Text Available Salmonella enterica infections are a significant global health issue, and development of vaccines against these bacteria requires an improved understanding of how vaccination affects the growth and spread of the bacteria within the host. We have combined in vivo tracking of molecularly tagged bacterial subpopulations with mathematical modelling to gain a novel insight into how different classes of vaccines and branches of the immune response protect against secondary Salmonella enterica infections of the mouse. We have found that a live Salmonella vaccine significantly reduced bacteraemia during a secondary challenge and restrained inter-organ spread of the bacteria in the systemic organs. Further, fitting mechanistic models to the data indicated that live vaccine immunisation enhanced both the bacterial killing in the very early stages of the infection and bacteriostatic control over the first day post-challenge. T-cell immunity induced by this vaccine is not necessary for the enhanced bacteriostasis but is required for subsequent bactericidal clearance of Salmonella in the blood and tissues. Conversely, a non-living vaccine while able to enhance initial blood clearance and killing of virulent secondary challenge bacteria, was unable to alter the subsequent bacterial growth rate in the systemic organs, did not prevent the resurgence of extensive bacteraemia and failed to control the spread of the bacteria in the body.

Vaccination uptake and awareness of a free hepatitis B vaccination program among female commercial sex workers.

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Baars, Jessica E; Boon, Brigitte J F; Garretsen, Henk F; van de Mheen, Dike

2009-01-01

We sought to explore the reach of a free hepatitis B vaccination program among female commercial sex workers (CSWs) within a legalized prostitution setting in the Netherlands. We also investigated the reasons for nonparticipation and noncompliance. In this cross-sectional study based on ethnographic mapping and targeted sampling, 259 CSWs were interviewed at their work in 3 regions in the Netherlands. The semistructured interviews contained questions on sociodemographics, sexual risk behavior, sex work, awareness of the opportunity to obtain free hepatitis B vaccination, vaccination uptake, and compliance with the full vaccination schedule. Of our sample, 79% reported awareness of the opportunity to obtain hepatitis B vaccination, and 63% reported to be vaccinated against hepatitis B (received > or =1 vaccination). A personal approach by health professionals or was associated with vaccination uptake, when specific sociodemographic variables, sexual behavior, and sex work related covariates were controlled for in the analysis. Window prostitution and the duration of working in the region were associated with awareness of the opportunity to obtain free hepatitis B vaccination. The results of this study suggest that outreach activities (i.e., a personal approach) within this program are beneficial. Transient CSWs are more difficult to reach within the current vaccination program. These results can be used to increase the success of future health programs among this risk group.

Effect of live Salmonella Ty21a in Dextran Sulfate Sodium-induced Colitis

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Gunnar Nysœter

2007-01-01

Full Text Available Background Intestinal microbiota seems to play an essential role in the development of inflammatory bowel diseases (IBD. We hypothesised that an oral vaccine based on live Salmonella typhi would be well tolerated and could even attenuate dextran sulfate sodium (DSS induced colitis in rats, an animal model of IBD. Methods Nine male Wistar rats was used for an initial tolerance study, in which we used 3 dose-levels of Salmonella Ty21a, 0.5 × 10 9 , 1 × 10 9 , and 2 × 10 9 CFU, each dose being tested in 3 rats. Four treatment groups consisting of 8 male Wistar rats per group: 1 control group given standard food and water, 2 control group given four daily administrations of Salmonella Ty21a 1 × 10 9 CFU, 3 water with 5% DSS the last 7 days, 4 four daily administrations of Salmonella Ty21a before water with 5% DSS the last 7 days. The Salmonella Ty21a was administered by gastric gavage on day 1, 3, 5 and 16, while DSS was given with the drinking water from day 15 to 22. The animals were sacrificed and colonic tissue removed for analysis 22 days after gavage of the first vaccine dose. Results The animals in the tolerance study got no signs of disease. In the treatment study, all animals receiving DSS had histologic indications of colitis, particularly in the distal part of the colon. Administration of Salmonella Ty21a had no significant effect on crypt and inflammation scores (p > 0.05. Conclusion Gastric administration of live vaccine strain Salmonella Ty21a was well tolerated, but did not provide any significant protection against development of DSS induced colitis in rats.

Overexpression of MicA induces production of OmpC-enriched outer membrane vesicles that protect against Salmonella challenge.

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Choi, Hyun-Il; Kim, Moonjeong; Jeon, Jinseong; Han, Jin Kwan; Kim, Kwang-Sun

2017-08-26

Outer membrane vesicles (OMVs) derived from bacteria are promising candidates for subunit vaccines. Stresses that modulate the composition of outer membrane proteins (OMPs) are important for OMV synthesis. Small RNAs (sRNAs) expressed in response to stress regulate OMPs, although the mechanism underlying sRNA-mediated OMV biogenesis and its utility for developing vaccine platforms remains to be elucidated. Here, we characterized the role of a sRNA, MicA, which regulates OmpA, a major OMP involved in both production of OMVs and reactive immunity against Salmonella challenge. A Salmonella strain overexpressing MicA generated more OMVs than a control strain. In addition, OmpC was the major component of MicA-derived OMV proteins. MicA-derived OMVs induced Th1- and Th17-type immune responses in vitro and reduced Salmonella-mediated lethality in a mouse model. Thus, OmpA-regulatory sRNA-derived OMVs may facilitate production of Salmonella-protective vaccines. Copyright © 2017 Elsevier Inc. All rights reserved.

Assessment of eight HPV vaccination programs implemented in lowest income countries

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Ladner Joël

2012-05-01

Full Text Available Abstract Background Cervix cancer, preventable, continues to be the third most common cancer in women worldwide, especially in lowest income countries. Prophylactic HPV vaccination should help to reduce the morbidity and mortality associated with cervical cancer. The purpose of the study was to describe the results of and key concerns in eight HPV vaccination programs conducted in seven lowest income countries through the Gardasil Access Program (GAP. Methods The GAP provides free HPV vaccine to organizations and institutions in lowest income countries. The HPV vaccination programs were entirely developed, implemented and managed by local institutions. Institutions submitted application forms with institution characteristics, target population, communication delivery strategies. After completion of the vaccination campaign (3 doses, institutions provided a final project report with data on doses administered and vaccination models. Two indicators were calculated, the program vaccination coverage and adherence. Qualitative data were also collected in the following areas: government and community involvement; communication, and sensitization; training and logistics resources, and challenges. Results A total of eight programs were implemented in seven countries. The eight programs initially targeted a total of 87,580 girls, of which 76,983 received the full 3-dose vaccine course, with mean program vaccination coverage of 87.8%; the mean adherence between the first and third doses of vaccine was 90.9%. Three programs used school-based delivery models, 2 used health facility-based models, and 3 used mixed models that included schools and health facilities. Models that included school-based vaccination were most effective at reaching girls aged 9-13 years. Mixed models comprising school and health facility-based vaccination had better overall performance compared with models using just one of the methods. Increased rates of program coverage and

Assessment of eight HPV vaccination programs implemented in lowest income countries.

Science.gov (United States)

Ladner, Joël; Besson, Marie-Hélène; Hampshire, Rachel; Tapert, Lisa; Chirenje, Mike; Saba, Joseph

2012-05-23

Cervix cancer, preventable, continues to be the third most common cancer in women worldwide, especially in lowest income countries. Prophylactic HPV vaccination should help to reduce the morbidity and mortality associated with cervical cancer. The purpose of the study was to describe the results of and key concerns in eight HPV vaccination programs conducted in seven lowest income countries through the Gardasil Access Program (GAP). The GAP provides free HPV vaccine to organizations and institutions in lowest income countries. The HPV vaccination programs were entirely developed, implemented and managed by local institutions. Institutions submitted application forms with institution characteristics, target population, communication delivery strategies. After completion of the vaccination campaign (3 doses), institutions provided a final project report with data on doses administered and vaccination models. Two indicators were calculated, the program vaccination coverage and adherence. Qualitative data were also collected in the following areas: government and community involvement; communication, and sensitization; training and logistics resources, and challenges. A total of eight programs were implemented in seven countries. The eight programs initially targeted a total of 87,580 girls, of which 76,983 received the full 3-dose vaccine course, with mean program vaccination coverage of 87.8%; the mean adherence between the first and third doses of vaccine was 90.9%. Three programs used school-based delivery models, 2 used health facility-based models, and 3 used mixed models that included schools and health facilities. Models that included school-based vaccination were most effective at reaching girls aged 9-13 years. Mixed models comprising school and health facility-based vaccination had better overall performance compared with models using just one of the methods. Increased rates of program coverage and adherence were positively correlated with the number of

Evaluation of a Salmonella Enteritidis vaccine and related ELISA for respective induction and assessment of acquired immunity to the vaccine and/or Echinacea purpurea in Awassi Ewes.

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Barbour, Elie K; Assi, Chibli A Abou; Shaib, Houssam; Hamadeh, Shadi; Murtada, Muhammad; Mahmoud, Ghassan; Yaghmoor, Soonham; Iyer, Archana; Harakeh, Steve; Kumosani, Taha

2015-05-05

The aim of this study was to evaluate an experimental Salmonella Enteritidis (SE) bacterin and an indirect ELISA system to assess quantitatively the acquired immunity in Awassi ewes to the vaccine and/or Echinacea purpurea (EP) dried roots. Four treatments of the ewes were included in the experimental design, with 6 ewes/treatment. The first treatment (T1) had the controls that were non-vaccinated and non-treated with EP. The T2 ewes were only treated with EP. The T3 and T4 ewes were vaccinated at D1 (initiation of trial) and D10, while the T4 ewes were additionally administered the EP dried roots. Blood was collected from the jugular vein of all ewes at D1, D10, D21 and D45. The construction of the vaccine and the ELISA are detailed within the manuscript. The ELISA was able to detect quantitatively the significant acquired primary and secondary immunity to the vaccine in T3 and T4 ewes, compared to their low level of background immunities at initiation of the experiment (p0.05) in T1 control ewes, and in the T2 ewes that were given only the (EP) (p>0.05). Moreover, the ELISA was able to uncover the significant seroconversion of secondary immune response in T4 ewes at D21 compared to that at D10 (pewes. This is the first work in literature that reports the need to supplement the vaccination by the experimental SE bacterin with daily oral intake of 250mg of EP-dried roots, effective the first vaccination day and up to 21 days, for obtaining a statistically significant seroconversion. Copyright © 2015 Elsevier Ltd. All rights reserved.

Cell-associated flagella enhance the protection conferred by mucosally-administered attenuated Salmonella Paratyphi A vaccines.

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Orit Gat

2011-11-01

Full Text Available Antibiotic-resistant Salmonella enterica serovar Paratyphi A, the agent of paratyphoid A fever, poses an emerging public health dilemma in endemic areas of Asia and among travelers, as there is no licensed vaccine. Integral to our efforts to develop a S. Paratyphi A vaccine, we addressed the role of flagella as a potential protective antigen by comparing cell-associated flagella with exported flagellin subunits expressed by attenuated strains.S. Paratyphi A strain ATCC 9150 was first deleted for the chromosomal guaBA locus, creating CVD 1901. Further chromosomal deletions in fliD (CVD 1901D or flgK (CVD 1901K were then engineered, resulting in the export of unpolymerized FliC, without impairing its overall expression. The virulence of the resulting isogenic strains was examined using a novel mouse LD(50 model to accommodate the human-host restricted S. Paratyphi A. The immunogenicity of the attenuated strains was then tested using a mouse intranasal model, followed by intraperitoneal challenge with wildtype ATCC 9150.Mucosal (intranasal immunization of mice with strain CVD 1901 expressing cell-associated flagella conferred superior protection (vaccine efficacy [VE], 90% against a lethal intraperitoneal challenge, compared with the flagellin monomer-exporting mutants CVD 1901K (30% VE or CVD 1901D (47% VE. The superior protection induced by CVD 1901 with its cell-attached flagella was associated with an increased IgG2a:IgG1 ratio of FliC-specific antibodies with enhanced opsonophagocytic capacity.Our results clearly suggest that enhanced anti-FliC antibody-mediated clearance of S. Paratyphi A by phagocytic cells, induced by vaccines expressing cell-associated rather than exported FliC, might be contributing to the vaccine-induced protection from S. Paratyphi A challenge in vivo. We speculate that an excess of IgG1 anti-FliC antibodies induced by the exported FliC may compete with the IgG2a subtype and block binding to specific phagocyte Fc

Compensation programs after withdrawal of the recommendation for HPV vaccine in Japan.

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Yuji, Koichiro; Nakada, Haruka

2016-05-03

HPV vaccinations were recommended with the backing of a Japanese government subsidy program in 2010, and were included in the National Immunization Program in April 2013. However, the Ministry of Health, Labour, and Welfare withdrew the recommendation for the HPV vaccination in June 2013. We investigated HPV vaccine injury compensation programs for both the national and local governments. Approximately 3.38 million girls were vaccinated, and 2,584 complained of health problems. The majority of these received the vaccine shot as a non-routine vaccination. In total, 98 people developed health problems and applied for assistance from 2011 to 2014, but no cases have been processed since October 2014. Several local governments are providing their own compensation program for cases of vaccine adverse reactions, but the number is extremely low (16 of 1,741 municipalities and 1 of 47 prefectures). The local governments that are providing compensation are largely those where HPV vaccine victim support groups are prominent. The confusion regarding the national program for HPV vaccine injury was caused by the discrepancy between the compensation programs for those vaccinated under the immunization law and for those who received voluntary vaccinations. The establishment of a new compensation program might be key to finding a lasting resolution.

Impact of Dietary Galacto-Oligosaccharide (GOS) on Chicken’s Gut Microbiota, Mucosal Gene Expression, and Salmonella Colonization

OpenAIRE

Rebecca-Ayme Hughes; Rebecca-Ayme Hughes; Riawana A. Ali; Mary A. Mendoza; Hosni M. Hassan; Matthew D. Koci

2017-01-01

Preventing Salmonella colonization in young birds is key to reducing contamination of poultry products for human consumption (eggs and meat). While several Salmonella vaccines have been developed that are capable of yielding high systemic antibodies, it is not clear how effective these approaches are at controlling or preventing Salmonella colonization of the intestinal tract. Effective alternative control strategies are needed to help supplement the bird’s ability to prevent Salmonella colon...

Impact of Skip-a-Day and Every-Day Feeding Programs for Broiler Breeder Pullets on the Recovery of Salmonella and Campylobacter following challenge.

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Wilson, K M; Bourassa, D V; McLendon, B L; Wilson, J L; Buhr, R J

2018-06-08

The impact of restrictive feeding programs on Salmonella and Campylobacter colonization and persistence after challenge was investigated for broiler breeder pullets housed in an experimental rearing facility. Pullet-chicks were placed on litter in 3 feeding program rooms and each room contained 2 replicate pens. The feeding programs were: (1) Skip-a-day in trough feeders (SAD); (2) Every-day in trough feeders (EDT); (3) Every-day on the pen litter (EDL). On d 1, an additional group of hatchmate chicks were housed in a separate room and gavaged with Salmonella Typhimurium, to later serve as seeder chicks. After seeders were confirmed Salmonella-positive at wk 4, at wk 5 seeders were placed into each feeding program pen to commingle with 135 penmates. At 7, 9, 11, 17, 18, and 20 wk the litter surface in each pen was sampled using intermittently stepped-on drag-swabs. At 8, 12, 16, and 20 wk of age the ceca were sampled from 10 penmates/pen and 2 pooled spleen samples/pen were collected. SAD litter remained Salmonella-positive through 20 wk of age while EDL and EDT pens had no detectible litter Salmonella recovery by 18 and 20 wk. EDL fed pens had no direct (days had significantly higher Salmonella recovery (40%), compared to EDT and EDL (both at 5% recovery). By 16 and 20 wk, only the SAD pullets on the on-feed day (48 h without feed) had recovery of Salmonella at 20%. Salmonella recovery in pooled spleen samples did not appear associated with feeding treatments (22% positive). The remaining pullets challenged with Campylobacter at 21 wk produced similar trends as was seen for Salmonella. SAD program pullets had significantly higher Campylobacter from ceca (80 to 100%) compared to pullets on EDL (30 to 60%) or EDT (40 to 95%). These results suggest that using a Skip-a-Day feeding program for broiler breeder pullets contributes to persistently higher Salmonella and Campylobacter ceca colonization and litter prevalence.

Cost-effectiveness of dog rabies vaccination programs in East Africa

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Borse, Rebekah H.; Atkins, Charisma Y.; Gambhir, Manoj; Undurraga, Eduardo A.; Blanton, Jesse D.; Kahn, Emily B.; Dyer, Jessie L.; Rupprecht, Charles E.

2018-01-01

Background Dog rabies annually causes 24,000–70,000 deaths globally. We built a spreadsheet tool, RabiesEcon, to aid public health officials to estimate the cost-effectiveness of dog rabies vaccination programs in East Africa. Methods RabiesEcon uses a mathematical model of dog-dog and dog-human rabies transmission to estimate dog rabies cases averted, the cost per human rabies death averted and cost per year of life gained (YLG) due to dog vaccination programs (US 2015 dollars). We used an East African human population of 1 million (approximately 2/3 living in urban setting, 1/3 rural). We considered, using data from the literature, three vaccination options; no vaccination, annual vaccination of 50% of dogs and 20% of dogs vaccinated semi-annually. We assessed 2 transmission scenarios: low (1.2 dogs infected per infectious dog) and high (1.7 dogs infected). We also examined the impact of annually vaccinating 70% of all dogs (World Health Organization recommendation for dog rabies elimination). Results Without dog vaccination, over 10 years there would a total of be approximately 44,000–65,000 rabid dogs and 2,100–2,900 human deaths. Annually vaccinating 50% of dogs results in 10-year reductions of 97% and 75% in rabid dogs (low and high transmissions scenarios, respectively), approximately 2,000–1,600 human deaths averted, and an undiscounted cost-effectiveness of $451-$385 per life saved. Semi-annual vaccination of 20% of dogs results in in 10-year reductions of 94% and 78% in rabid dogs, and approximately 2,000–1,900 human deaths averted, and cost $404-$305 per life saved. In the low transmission scenario, vaccinating either 50% or 70% of dogs eliminated dog rabies. Results were most sensitive to dog birth rate and the initial rate of dog-to-dog transmission (Ro). Conclusions Dog rabies vaccination programs can control, and potentially eliminate, dog rabies. The frequency and coverage of vaccination programs, along with the level of dog rabies

School-Based Influenza Vaccination: Health and Economic Impact of Maine's 2009 Influenza Vaccination Program.

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Basurto-Dávila, Ricardo; Meltzer, Martin I; Mills, Dora A; Beeler Asay, Garrett R; Cho, Bo-Hyun; Graitcer, Samuel B; Dube, Nancy L; Thompson, Mark G; Patel, Suchita A; Peasah, Samuel K; Ferdinands, Jill M; Gargiullo, Paul; Messonnier, Mark; Shay, David K

2017-12-01

To estimate the societal economic and health impacts of Maine's school-based influenza vaccination (SIV) program during the 2009 A(H1N1) influenza pandemic. Primary and secondary data covering the 2008-09 and 2009-10 influenza seasons. We estimated weekly monovalent influenza vaccine uptake in Maine and 15 other states, using difference-in-difference-in-differences analysis to assess the program's impact on immunization among six age groups. We also developed a health and economic Markov microsimulation model and conducted Monte Carlo sensitivity analysis. We used national survey data to estimate the impact of the SIV program on vaccine coverage. We used primary data and published studies to develop the microsimulation model. The program was associated with higher immunization among children and lower immunization among adults aged 18-49 years and 65 and older. The program prevented 4,600 influenza infections and generated $4.9 million in net economic benefits. Cost savings from lower adult vaccination accounted for 54 percent of the economic gain. Economic benefits were positive in 98 percent of Monte Carlo simulations. SIV may be a cost-beneficial approach to increase immunization during pandemics, but programs should be designed to prevent lower immunization among nontargeted groups. © Health Research and Educational Trust.

Live recombinant Salmonella Typhi vaccines constructed to investigate the role of rpoS in eliciting immunity to a heterologous antigen.

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Huoying Shi

2010-06-01

Full Text Available We hypothesized that the immunogenicity of live Salmonella enterica serovar Typhi vaccines expressing heterologous antigens depends, at least in part, on its rpoS status. As part of our project to develop a recombinant attenuated S. Typhi vaccine (RASTyV to prevent pneumococcal diseases in infants and children, we constructed three RASTyV strains synthesizing the Streptococcus pneumoniae surface protein PspA to test this hypothesis. Each vector strain carried ten engineered mutations designed to optimize safety and immunogenicity. Two S. Typhi vector strains (chi9639 and chi9640 were derived from the rpoS mutant strain Ty2 and one (chi9633 from the RpoS(+ strain ISP1820. In chi9640, the nonfunctional rpoS gene was replaced with the functional rpoS gene from ISP1820. Plasmid pYA4088, encoding a secreted form of PspA, was moved into the three vector strains. The resulting RASTyV strains were evaluated for safety in vitro and for immunogenicity in mice. All three RASTyV strains were similar to the live attenuated typhoid vaccine Ty21a in their ability to survive in human blood and human monocytes. They were more sensitive to complement and were less able to survive and persist in sewage and surface water than their wild-type counterparts. Adult mice intranasally immunized with any of the RASTyV strains developed immune responses against PspA and Salmonella antigens. The RpoS(+ vaccines induced a balanced Th1/Th2 immune response while the RpoS(- strain chi9639(pYA4088 induced a strong Th2 immune response. Immunization with any RASTyV provided protection against S. pneumoniae challenge; the RpoS(+ strain chi9640(pYA4088 provided significantly greater protection than the ISP1820 derivative, chi9633(pYA4088. In the pre-clinical setting, these strains exhibited a desirable balance between safety and immunogenicity and are currently being evaluated in a Phase 1 clinical trial to determine which of the three RASTyVs has the optimal safety and

Evaluation of a Salmonella vectored vaccine expressing Mycobacterium avium subsp. paratuberculosis antigens against challenge in a goat model.

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Syed M Faisal

Full Text Available Johnes disease (JD, caused by Mycobacterium avium subsp paratuberculosis (MAP, occurs worldwide as chronic granulomatous enteritis of domestic and wild ruminants. To develop a cost effective vaccine, in a previous study we constructed an attenuated Salmonella strain that expressed a fusion product made up of partial fragments of MAP antigens (Ag85A, Ag85B and SOD that imparted protection against challenge in a mouse model. In the current study we evaluated the differential immune response and protective efficacy of the Sal-Ag vaccine against challenge in a goat model as compared to the live attenuated vaccine MAP316F. PBMCs from goats vaccinated with Sal-Ag and challenged with MAP generated significantly lower levels of IFN-γ, following in vitro stimulation with either Antigen-mix or PPD jhonin, than PBMC from MAP316F vaccinated animals. Flow cytometric analysis showed the increase in IFN-γ correlated with a significantly higher level of proliferation of CD4, CD8 and γδT cells and an increased expression of CD25 and CD45R0 in MAP316F vaccinated animals as compared to control animals. Evaluation of a range of cytokines involved in Th1, Th2, Treg, and Th17 immune responses by quantitative PCR showed low levels of expression of Th1 (IFN-γ, IL-2, IL-12 and proinflammatory cytokines (IL-6, IL-8, IL-18, TNF-α in the Sal-Ag immunized group. Significant levels of Th2 and anti-inflammatory cytokines transcripts (IL-4, IL-10, IL-13, TGF-β were expressed but their level was low and with a pattern similar to the control group. Over all, Sal-Ag vaccine imparted partial protection that limited colonization in tissues of some animals upon challenge with wild type MAP but not to the level achieved with MAP316F. In conclusion, the data indicates that Sal-Ag vaccine induced only a low level of protective immunity that failed to limit the colonization of MAP in infected animals. Hence the Sal-Ag vaccine needs further refinement to increase its efficacy.

Human Papillomavirus Vaccine as an Anti-cancer Vaccine: Collaborative Efforts to Promote HPV Vaccine in the National Comprehensive Cancer Control Program

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Townsend, Julie S.; Steele, C. Brooke; Hayes, Nikki; Bhatt, Achal; Moore, Angela R.

2018-01-01

Background Widespread use of the HPV vaccine has the potential to reduce incidence from HPV-associated cancers. However, vaccine uptake among adolescents remains well below the Healthy People 2020 targets. The Centers for Disease Control and Prevention (CDC)’s National Comprehensive Cancer Control Program awardees (NCCCP) are well positioned to work with immunization programs to increase vaccine uptake. Methods CDC’s chronic disease management information system was queried for objectives and activities associated with HPV vaccine that were reported by NCCCP awardees from 2013 – 2016 as part of program reporting requirements. A content analysis was conducted on the query results to categorize interventions according to strategies outlined in The Guide to Community Preventive Services and the 2014 President’s Cancer Panel report. Results Sixty-two percent of NCCCP awardees had planned or implemented at least one activity since 2013 to address low HPV vaccination coverage in their jurisdictions. Most NCCCP awardees (86%) reported community education activities, while 65% reported activities associated with provider education. Systems-based strategies such as client reminders or provider assessment and feedback were each reported by less than 25% of NCCCP awardees. Conclusion Many NCCCP awardees report planning or implementing activities to address low HPV vaccination coverage, often in conjunction with state immunization programs. NCCCP awardees can play a role in increasing HPV vaccination coverage through their cancer prevention and control expertise and access to partners in the health care community. PMID:28263672

The new classification system for slaughter-pig herds in the Danish Salmonella surveillance-and-control program

DEFF Research Database (Denmark)

Alban, L.; Stege, Helle; Dahl, J.

2002-01-01

the Danish Salmonella Database including all herds in 2000. The classification scheme has been adjusted on the following points. (1) The sampling has been simplified into 60, 75, or 100 samples per herd per year depending on herd size. This means more-precise estimates for the seroprevalence among smaller......The Danish surveillance-and-control program for Salmonella in slaughter pigs was introduced in 1995. The key element of the program is a quick and correct identification of herds with high seroprevalence. After 5 years, the classification scheme was evaluated-and a revision was made. Data from two...

How to become a top model: impact of animal experimentation on human Salmonella disease research.

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Tsolis, Renée M; Xavier, Mariana N; Santos, Renato L; Bäumler, Andreas J

2011-05-01

Salmonella serotypes are a major cause of human morbidity and mortality worldwide. Over the past decades, a series of animal models have been developed to advance vaccine development, provide insights into immunity to infection, and study the pathogenesis of human Salmonella disease. The successive introduction of new animal models, each suited to interrogate previously neglected aspects of Salmonella disease, has ushered in important conceptual advances that continue to have a strong and sustained influence on the ideas driving research on Salmonella serotypes. This article reviews important milestones in the use of animal models to study human Salmonella disease and identify research needs to guide future work.

Immunization with the conjugate vaccine Vi-CRM₁₉₇ against Salmonella typhi induces Vi-specific mucosal and systemic immune responses in mice.

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Fiorino, Fabio; Ciabattini, Annalisa; Rondini, Simona; Pozzi, Gianni; Martin, Laura B; Medaglini, Donata

2012-09-21

Typhoid fever is a public health problem, especially among young children in developing countries. To address this need, a glycoconjugate vaccine Vi-CRM₁₉₇, composed of the polysaccharide antigen Vi covalently conjugated to the non-toxic mutant of diphtheria toxin CRM₁₉₇, is under development. Here, we assessed the antibody and cellular responses, both local and systemic, following subcutaneous injection of Vi-CRM₁₉₇. The glycoconjugate elicited Vi-specific serum IgG titers significantly higher than unconjugated Vi, with prevalence of IgG1 that persisted for at least 60 days after immunization. Vi-specific IgG, but not IgA, were present in intestinal washes. Lymphocytes proliferation after restimulation with Vi-CRM₁₉₇ was observed in spleen and mesenteric lymph nodes. These data confirm the immunogenicity of Vi-CRM₁₉₇ and demonstrate that the vaccine-specific antibody and cellular immune responses are present also in the intestinal tract, thus strengthening the suitability of Vi-CRM₁₉₇ as a promising candidate vaccine against Salmonella Typhi. Copyright © 2012 Elsevier Ltd. All rights reserved.

Barriers and Facilitators of HPV Vaccination in the VFC Program.

Science.gov (United States)

Fleming, Wayne S; Sznajder, Kristin K; Nepps, Margaret; Boktor, Sameh W

2018-06-01

This study determined facilitators and barriers to human papillomavirus (HPV) vaccination perceived by providers of healthcare in the federally funded Pennsylvania Vaccines for Children (PA VFC) program. The cross-sectional study gathered descriptive data through a survey research design. Providers of healthcare were recruited through an email containing a link to an 18-question online survey. The survey was divided into four main sections which assessed the perceived facilitators and barriers to HPV vaccination of PA VFC program-eligibles. Survey respondents represented 65 of 66 Pennsylvania counties covered by the PA VFC Program. The study recruited 772 PA VFC participating healthcare facilities for a response rate of 52%. Ninety eight percent of the responding facilities reported that they offered the HPV vaccine. The most common barriers to vaccine administration were the parental belief that HPV vaccination is associated with sexual activity and parent/patient refusal of the HPV vaccination which together accounted for (44%) of responses. The majority of respondents (75.6%) indicated counseling parents and adolescents on the benefits of HPV vaccination was a very important factor in HPV vaccination uptake. Healthcare provider facility based training (32%) and web-based training for healthcare providers (22%) were the most recommended avenues for HPV training. The most common barrier to HPV vaccination was identified as the parental misconception that HPV vaccination is associated with sexual activity. Providers believed that the best way to increase HPV vaccination is through counseling parents and adolescents on the benefits of HPV vaccination and to correct misconceptions and change attitudes. Providers are desirous of receiving HPV web-based or workplace training.

Oral Vaccination with Salmonella enterica as a Cruzipain-DNA Delivery System Confers Protective Immunity against Trypanosoma cruzi▿

Science.gov (United States)

Cazorla, Silvia I.; Becker, Pablo D.; Frank, Fernanda M.; Ebensen, Thomas; Sartori, María J.; Corral, Ricardo S.; Malchiodi, Emilio L.; Guzmán, Carlos A.

2008-01-01

To stimulate both local and systemic immune responses against Trypanosoma cruzi, Salmonella enterica serovar Typhimurium aroA was exploited as a DNA delivery system for cruzipain (SCz). In a murine model we compared SCz alone (GI) or coadministered with Salmonella carrying a plasmid encoding granulocyte-macrophage colony-stimulating factor (GII), as well as protocols in which SCz priming was followed by boosting with recombinant cruzipain (rCz) admixed with either CpG-ODN (GIII) or MALP-2, a synthetic derivative of a macrophage-activating lipopeptide of 2 kDa from Mycoplasma fermentans (GIV). The results showed that protocols that included four oral doses of SCz (GI) elicited mainly a mucosal response characterized by immunoglobulin A (IgA) secretion and proliferation of gut-associated lymphoid tissue cells, with weak systemic responses. In contrast, the protocol that included a boost with rCz plus CpG (GIII) triggered stronger systemic responses in terms of Cz-specific serum IgG titers, splenocyte proliferation, gamma interferon (IFN-γ) secretion, and delayed-type hypersensitivity response. Trypomastigote challenge of vaccinated mice resulted in significantly lower levels of parasitemia compared to controls. Protection was abolished by depletion of either CD4+ or CD8+ T cells. Parasite control was also evident from the reduction of tissue damage, as revealed by histopathologic studies and serum levels of enzymes that are markers of muscle injury in chronic Chagas' disease (i.e., creatine kinase, aspartate aminotransferase, and lactate dehydrogenase). Enhanced release of IFN-γ and interleukin-2 was observed in GI and GII upon restimulation of splenocytes in the nonparasitic phase of infection. Our results indicate that Salmonella-mediated delivery of Cz-DNA by itself promotes the elicitation of an immune response that controls T. cruzi infection, thereby reducing parasite loads and subsequent damage to muscle tissues. PMID:17967857

The introduction of new vaccines into developing countries. IV: Global Access Strategies.

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Mahoney, Richard T; Krattiger, Anatole; Clemens, John D; Curtiss, Roy

2007-05-16

This paper offers a framework for managing a comprehensive Global Access Strategy for new vaccines in developing countries. It is aimed at strengthening the ability of public-sector entities to reach their goals. The Bill and Melinda Gates Foundation and The Rockefeller Foundation have been leaders in stimulating the creation of new organizations - public/private product development partnerships (PDPs) - that seek to accelerate vaccine development and distribution to meet the health needs of the world's poor. Case studies of two of these PDPs - the Salmonella Anti-pneumococcal Vaccine Program and the Pediatric Dengue Vaccine Initiative - examine development of such strategies. Relying on the application of innovation theory, the strategy leads to the identification of six Components of Innovation which cover all aspects of the vaccine innovation process. Appropriately modified, the proposed framework can be applied to the development and introduction of other products in developing countries including drugs, and nutritional and agricultural products.

What Have We Learned From the Typhoid Fever Surveillance in Africa Program?

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Baker, Stephen; Hombach, Joachim; Marks, Florian

2016-03-15

The Typhoid Fever Surveillance in Africa Program (TSAP) was established in 2009 to fill the data void concerning invasive Salmonella disease in sub-Saharan Africa, and to specifically estimate the burden of bloodstream infections caused by the key pathogen, Salmonella enterica serovar Typhi. TSAP has achieved this ambitious target, finding high incidences of typhoid fever in both rural and urban populations in several countries in sub-Saharan Africa. The results of TSAP will undoubtedly dictate the direction of future typhoid fever research in Africa, and at last provides a key piece of the disease burden jigsaw puzzle. With the dawn of new Vi conjugate vaccines against Salmonella Typhi, the next priority for the typhoid community must be providing the required data on these vaccines so they can be licensed and provided to those in high-risk groups and locations across sub-Saharan Africa. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America.

No-fault vaccine insurance: lessons from the National Vaccine Injury Compensation Program.

Science.gov (United States)

Ridgway, D

1999-02-01

During the first eight years of the National Vaccine Injury Compensation Program (NVICP), 786 contested claims were resolved through published judicial opinions. The likelihood of compensation dependent in part on the closeness of the match between the described injury and a specified list of acknowledged untoward vaccine side effects. In addition, the chances of applicant success were influenced by the applicant's choice of attorney and expert witnesses, by the assignment of the Special Master to decide the case, and increasingly over time, by the applicant's ability to comply with procedural requirements. The majority of contested claims arose from pertussis immunizations. For pertussis claims, the goal of insulating manufacturers from product liability suits has been achieved by granting compensation to applicants whose injuries are not scientifically recognized effects of the vaccine. In spite of (or because of) this jarring contradiction between the legal and medical understanding of causation, vaccine availability and childhood immunization rates improved during the early years of the plan. The apparent success of the program may encourage the substitution of no-fault compensation plans for tort-based consumer protection for other products, both medical and nonmedical.

Isolation of OmpA gene from Salmonella typhimurium and ...

African Journals Online (AJOL)

Isolation of OmpA gene from Salmonella typhimurium and transformation into alfalfa in order to develop an edible plant based vaccine. ... The recombinant OmpA was expressed in Escherichia coli TG1. The new construct was used to transform the Agrobacterium tumefaciens Strain LBA4404 before plant transformation.

Survey of Salmonella contamination in chicken layer farms in three Caribbean countries.

Science.gov (United States)

Adesiyun, Abiodun; Webb, Lloyd; Musai, Lisa; Louison, Bowen; Joseph, George; Stewart-Johnson, Alva; Samlal, Sannandan; Rodrigo, Shelly

2014-09-01

This study was conducted to investigate the demography, management, and production practices on layer chicken farms in Trinidad and Tobago, Grenada, and St. Lucia and the frequency of risk factors for Salmonella infection. The frequency of isolation of Salmonella from the layer farm environment, eggs, feeds, hatchery, and imported day-old chicks was determined using standard methods. Of the eight risk factors (farm size, age group of layers, source of day-old chicks, vaccination, sanitation practices, biosecurity measures, presence of pests, and previous disease outbreaks) for Salmonella infection investigated, farm size was the only risk factor significantly associated (P = 0.031) with the prevalence of Salmonella; 77.8% of large farms were positive for this pathogen compared with 33.3 and 26.1% of medium and small farms, respectively. The overall isolation rate of Salmonella from 35 layer farms was 40.0%. Salmonella was isolated at a significantly higher rate (P hatcheries, and airports in this country were negative. Salmonella Anatum, Salmonella group C, and Salmonella Kentucky were the predominant serotypes in Trinidad and Tobago, Grenada, and St. Lucia, respectively. Although Salmonella infections were found in layer birds sampled, table eggs appear to pose minimal risk to consumers. However, the detection of Salmonella -contaminated farm environments and feeds cannot be ignored. Only 2.9% of the isolates belonged to Salmonella Enteritidis, a finding that may reflect the impact of changes in farm management and poultry production in the region.

Cost-benefit comparisons of investments in improved water supply and cholera vaccination programs.

Science.gov (United States)

Jeuland, Marc; Whittington, Dale

2009-05-18

This paper presents the first cost-benefit comparison of improved water supply investments and cholera vaccination programs. Specifically, we compare two water supply interventions -- deep wells with public hand pumps and biosand filters (an in-house, point-of-use water treatment technology) -- with two types of cholera immunization programs with new-generation vaccines -- general community-based and targeted and school-based programs. In addition to these four stand-alone investments, we also analyze five combinations of water and vaccine interventions: (1) borehole+hand pump and community-based cholera vaccination, (2) borehole+hand pump and school-based cholera vaccination, (3) biosand filter and community-based cholera vaccination, (4) biosand filter and school-based cholera vaccination, and (5) biosand filter and borehole+hand pump. Using recent data applicable to developing country locations for parameters such as disease incidence, the effectiveness of vaccine and water supply interventions against diarrheal diseases, and the value of a statistical life, we construct cost-benefit models for evaluating these interventions. We then employ probabilistic sensitivity analysis to estimate a frequency distribution of benefit-cost ratios for all four interventions, given a wide variety of possible parameter combinations. Our results demonstrate that there are many plausible conditions in developing countries under which these interventions will be attractive, but that the two improved water supply interventions and the targeted cholera vaccination program are much more likely to yield attractive cost-benefit outcomes than a community-based vaccination program. We show that implementing community-based cholera vaccination programs after borehole+hand pump or biosand filters have already been installed will rarely be justified. This is especially true when the biosand filters are already in place, because these achieve substantial cholera risk reductions on their own

Estimating the Population-Level Effectiveness of Vaccination Programs in the Netherlands.

NARCIS (Netherlands)

van Wijhe, Maarten; McDonald, Scott A; de Melker, Hester E; Postma, Maarten J; Wallinga, Jacco

There are few estimates of the effectiveness of long-standing vaccination programs in developed countries. To fill this gap, we investigate the direct and indirect effectiveness of childhood vaccination programs on mortality at the population level in the Netherlands.

Effectiveness and acceptance of a health care-based mandatory vaccination program.

Science.gov (United States)

Leibu, Rachel; Maslow, Joel

2015-01-01

To decrease the risk of transmission of hospital-associated transmission of influenza and pertussis through mandatory vaccination of staff. A mandatory influenza and toxoid-diphtheria toxoid-acellular pertussis program was implemented systemwide. A structured vaccine exemption program was implemented for those requesting a medical and/or religious/moral/ethical exemption. Systemwide influenza vaccination rates increased from 67% historically, 76.2% in the 2012 to 2013 influenza season, to 94.7% in 2013 to 2014 with an overall compliance rate of 97.8%. Toxoid-diphtheria toxoid-acellular pertussis vaccination rates systemwide reached 94.9%, with an overall compliance rate of 98%. Higher rates were experienced at individual hospital facilities compared with the corporate location. Successful vaccination campaign outcomes can be achieved through diligent enforcement of mandatory vaccination, masking, and other infection prevention procedures.

Costs of vaccine programs across 94 low- and middle-income countries.

Science.gov (United States)

Portnoy, Allison; Ozawa, Sachiko; Grewal, Simrun; Norman, Bryan A; Rajgopal, Jayant; Gorham, Katrin M; Haidari, Leila A; Brown, Shawn T; Lee, Bruce Y

2015-05-07

While new mechanisms such as advance market commitments and co-financing policies of the GAVI Alliance are allowing low- and middle-income countries to gain access to vaccines faster than ever, understanding the full scope of vaccine program costs is essential to ensure adequate resource mobilization. This costing analysis examines the vaccine costs, supply chain costs, and service delivery costs of immunization programs for routine immunization and for supplemental immunization activities (SIAs) for vaccines related to 18 antigens in 94 countries across the decade, 2011-2020. Vaccine costs were calculated using GAVI price forecasts for GAVI-eligible countries, and assumptions from the PAHO Revolving Fund and UNICEF for middle-income countries not supported by the GAVI Alliance. Vaccine introductions and coverage levels were projected primarily based on GAVI's Adjusted Demand Forecast. Supply chain costs including costs of transportation, storage, and labor were estimated by developing a mechanistic model using data generated by the HERMES discrete event simulation models. Service delivery costs were abstracted from comprehensive multi-year plans for the majority of GAVI-eligible countries and regression analysis was conducted to extrapolate costs to additional countries. The analysis shows that the delivery of the full vaccination program across 94 countries would cost a total of $62 billion (95% uncertainty range: $43-$87 billion) over the decade, including $51 billion ($34-$73 billion) for routine immunization and $11 billion ($7-$17 billion) for SIAs. More than half of these costs stem from service delivery at $34 billion ($21-$51 billion)-with an additional $24 billion ($13-$41 billion) in vaccine costs and $4 billion ($3-$5 billion) in supply chain costs. The findings present the global costs to attain the goals envisioned during the Decade of Vaccines to prevent millions of deaths by 2020 through more equitable access to existing vaccines for people in all

Assessment of eight HPV vaccination programs implemented in lowest income countries

OpenAIRE

Ladner, Joël; Besson, Marie-Hélène; Hampshire, Rachel; Tapert, Lisa; Chirenje, Mike; Saba, Joseph

2012-01-01

Abstract Background Cervix cancer, preventable, continues to be the third most common cancer in women worldwide, especially in lowest income countries. Prophylactic HPV vaccination should help to reduce the morbidity and mortality associated with cervical cancer. The purpose of the study was to describe the results of and key concerns in eight HPV vaccination programs conducted in seven lowest income countries through the Gardasil Access Program (GAP). Methods The GAP provides free HPV vaccin...

Comparative assessment of immunization coverage of migrant children between national immunization program vaccines and non-national immunization program vaccines in East China.

Science.gov (United States)

Hu, Yu; Luo, Shuying; Tang, Xuewen; Lou, Linqiao; Chen, Yaping; Guo, Jing

2015-01-01

This study aimed to describe the disparities in immunization coverage between National Immunization Program (NIP) vaccines and non-NIP vaccines in Yiwu and to identify potential determinants. A face-to-face interview-based questionnaire survey among 423 migrant children born from 1 June 2010 to 31 May 2013 was conducted. Immunization coverage was estimated according to the vaccines scheduled at different age, the birth cohorts, and socio- demographic characteristics. Single-level logistic regression analysis was applied to identify the determinants of coverage of non-NIP vaccines. We found that NIP vaccines recorded higher immunization coverage compared with non-NIP vaccines (87.9100%- vs 0%-74.8%). Among the non-NIP vaccines, varicella vaccine (VarV) recorded the highest coverage of 85.4%, which was introduced in 1998; while 7-valent pneumococcal conjugate vaccine(PCV7) recorded the lowest coverage of 0% for primary series, which was introduced recently. Lower coverage rate of non-NIP vaccines was significantly associated with more siblings in household, shorter duration of living in the surveyed areas, lower family income, mother with a job, mother with poor awareness of vaccination, and mother with lower education level. We found the immunization coverage rate of non-NIP vaccines was significant lower than that of NIP vaccines. Expansion of NIP to include non-NIP vaccines can provide better protection against the vaccine preventable diseases through increased immunization coverage.

Assessment of a strain 19 brucellosis vaccination program in elk

Science.gov (United States)

Maichak, Eric J.; Scurlock, Brandon M.; Cross, Paul C.; Rogerson, Jared D.; Edwards, William H.; Wise, Benjamin; Smith, Scott G.; Kreeger, Terry J.

2017-01-01

Zoonotic diseases in wildlife present substantial challenges and risks to host populations, susceptible domestic livestock populations, and affected stakeholders. Brucellosis, a disease caused by the bacterium Brucella abortus, is endemic among elk (Cervus canadensis) attending winter feedgrounds and adjacent areas of western Wyoming, USA. To minimize transmission of brucellosis from elk to elk and elk to livestock, managers initiated a B. abortus strain 19 ballistic vaccination program in 1985. We used brucellosis prevalence (1971–2015) and reproductive outcome (2006–2015) data collected from female elk attending feedgrounds to assess efficacy of the strain 19 program while controlling for potentially confounding factors such as site and age. From our generalized linear models, we found that seroprevalence of brucellosis was 1) not lower following inception of vaccination; 2) not inversely associated with proportion of juveniles vaccinated over time; 3) not inversely associated with additional yearlings and adults vaccinated over time; and 4) associated more with feeding end-date than proportion of juveniles vaccinated. Using vaginal implant transmitters in adult females that were seropositive for brucellosis, we found little effect of vaccination coverage at reducing reproductive failures (i.e., abortion or stillbirth). Because we found limited support for efficacy of the strain 19 program, we support research to develop an oral vaccine and suggest that continuing other spatio-temporal management actions will be most effective to minimize transmission of brucellosis and reduce dependency of elk on supplemental winter feeding.

Evaluation of vaccine candidate potential of deltaaroA, deltahtrA and deltaaroAdeltahtrA mutants of Salmonella enterica subspecies enterica serovar Abortusequi in guinea pigs.

Science.gov (United States)

Singh, Bhoj Raj; Chandra, Mudit; Hansda, Dhananjoy; Alam, Javed; Babu, Narayanan; Siddiqui, Mehtab Z; Agrawal, Ravi K; Sharma, Gautam

2013-04-01

Salmonella enterica subspecies enterica serovar Abortusequi (S. Abortusequi), a host adapted Salmonella causes abortions, still births and foal mortality in equids. Though known since more than 100 years, it is still a problem in many of the developing countries including India. There is dearth of really good vaccine affording immunity lasting at least for one full gestation. In search of a potential vaccine candidate, three defined deletion mutants (deltaaroA, deltahtrA and deltaaroAdeltahtrA) of S. Abortusequi were tested in guinea pig model for attenuation, safety, immunogenicity, humoral immune response, protective efficacy and persistence in host. The deltahtrA and deltaaroAdeltahtrA mutants were found to be safe on oral inoculation in doses as high as 4.2 x 10(9) cfu/animal. Also through subcutaneous inoculation deltaaroAdeltahtrA mutant did not induce any abortion in pregnant guinea pigs. All the three mutants did not induce any illness or death in 1-2 week-old baby guinea pigs except deltahtrA mutant which caused mortality on intraperitoneal inoculation. Inoculation with mutants protected against challenge and increased breeding efficiency of guinea pigs. After >4.5 months of mutant inoculation, guinea pigs were protected against abortifacient dose of wild type S. Abortusequi and mother guinea pigs also conferred resistance to their babies to the similar challenge. Early humoral immune response of S. Abortusequi mutants was characteristic. Faecal excretion of deltaaroA and htrA mutants was detected up to 45 days of inoculation in guinea pigs while deltaaroAdeltahtrA mutant could not be detected after 21 days of inoculation. The results indicated that the double deletion mutant (deltaaroAdeltahtrA) was the most effective and safe candidate for vaccination against S. Abortusequi through mucosal route of inoculation.

Effectiveness and Cost-Benefit of an Influenza Vaccination Program for Health Care Workers

Directory of Open Access Journals (Sweden)

Annalee Yassi

1991-01-01

Full Text Available This study retrospectively reviewed the effectiveness of a vaccination program for hospital workers in a large tertiary care hospital, quantified influenza-induced absenteeism, and examined the factors determining the costs and benefits of this program. Absenteeism among high risk hospital workers was increased by 35% (P=0.001 during the virulent influenza epidemic of 1987–88. Benefits, measured as the value of sick time avoided, compared with costs, including materials, occupational nursing staff time, employee time during vaccination, and time lost due to adverse reactions, revealed a net benefit of $39.23 per vaccinated employee. Sensitivity analyses highlighted vaccine efficacy and absenteeism due to influenza and adverse reactions to vaccination as the most important factors; with time lost due to adverse reactions as much as 0.013 days per vaccinated employee and a vaccine efficacy of 70%, net positive benefits could be achieved if influenza-induced absenteeism is 0.5% or greater of paid employee time during the epidemic season. The results suggested that the net cost-benefit of a hospital employee vaccination program to decrease both employee morbidity and nosocomial influenza among patients, would be increased by active promotion of the vaccination program, especially for employees in high risk areas.

Oral vaccination with attenuated Salmonella choleraesuis C500 ...

African Journals Online (AJOL)

Helicobacter pylori are well known as the major gastro-duodenal pathogen of peptic ulcer disease and gastric cancer. Recombinant H. pylori vaccine comprising a single subunit antigen can only induce immune response with limited protection efficiency. Development of oral vaccine would be a new effective strategy for the ...

Introducing a pneumococcal vaccine to an existing influenza immunization program : vaccination rates and predictors of noncompliance

NARCIS (Netherlands)

Opstelten, W; Hak, E; Verheij, T J; van Essen, G A

2001-01-01

PURPOSE: Influenza vaccination has been recommended for all elderly people in The Netherlands since 1996, with greater than 80% compliance. It is unknown, however, if the addition of another vaccine to this immunization program will affect compliance. SUBJECTS AND METHODS: General practitioners

Comparative assessment of immunization coverage of migrant children between national immunization program vaccines and non-national immunization program vaccines in East China

Science.gov (United States)

Hu, Yu; Luo, Shuying; Tang, Xuewen; Lou, Linqiao; Chen, Yaping; Guo, Jing

2015-01-01

This study aimed to describe the disparities in immunization coverage between National Immunization Program (NIP) vaccines and non-NIP vaccines in Yiwu and to identify potential determinants. A face-to-face interview-based questionnaire survey among 423 migrant children born from 1 June 2010 to 31 May 2013 was conducted. Immunization coverage was estimated according to the vaccines scheduled at different age, the birth cohorts, and socio- demographic characteristics. Single-level logistic regression analysis was applied to identify the determinants of coverage of non-NIP vaccines. We found that NIP vaccines recorded higher immunization coverage compared with non-NIP vaccines (87.9100%– vs 0%-74.8%). Among the non-NIP vaccines, varicella vaccine (VarV) recorded the highest coverage of 85.4%, which was introduced in 1998; while 7-valent pneumococcal conjugate vaccine(PCV7) recorded the lowest coverage of 0% for primary series, which was introduced recently. Lower coverage rate of non-NIP vaccines was significantly associated with more siblings in household, shorter duration of living in the surveyed areas, lower family income, mother with a job, mother with poor awareness of vaccination, and mother with lower education level. We found the immunization coverage rate of non-NIP vaccines was significant lower than that of NIP vaccines. Expansion of NIP to include non-NIP vaccines can provide better protection against the vaccine preventable diseases through increased immunization coverage. PMID:25760670

Salmonella Typhi genomics: envisaging the future of typhoid eradication.

Science.gov (United States)

Yap, Kien-Pong; Thong, Kwai Lin

2017-08-01

Next-generation whole-genome sequencing has revolutionised the study of infectious diseases in recent years. The availability of genome sequences and its understanding have transformed the field of molecular microbiology, epidemiology, infection treatments and vaccine developments. We review the key findings of the publicly accessible genomes of Salmonella enterica serovar Typhi since the first complete genome to the most recent release of thousands of Salmonella Typhi genomes, which remarkably shape the genomic research of S. Typhi and other pathogens. Important new insights acquired from the genome sequencing of S. Typhi, pertaining to genomic variations, evolution, population structure, antibiotic resistance, virulence, pathogenesis, disease surveillance/investigation and disease control are discussed. As the numbers of sequenced genomes are increasing at an unprecedented rate, fine variations in the gene pool of S. Typhi are captured in high resolution, allowing deeper understanding of the pathogen's evolutionary trends and its pathogenesis, paving the way to bringing us closer to eradication of typhoid through effective vaccine/treatment development. © 2017 John Wiley & Sons Ltd.

Salmonella Typhimurium infection in the porcine intestine

DEFF Research Database (Denmark)

Schauser, Kirsten; Olsen, John Elmerdahl; Larsson, Lars-Inge

2005-01-01

The normal intestinal epithelium is renewed with a turnover rate of 3-5 days. During Salmonella infection increased cell loss is observed, possibly as a result of programmed cell death (PCD). We have, therefore, studied the effects of Salmonella Typhimurium infection on three elements involved...... in scattered epithelial cells and the number of positive cells increased with increasing times of exposure to Salmonella (P

Negative attitude of highly educated parents and health care workers towards future vaccinations in the Dutch childhood vaccination program

NARCIS (Netherlands)

Hak, E; Schönbeck, Y; De Melker, H; Van Essen, G A; Sanders, E A M

2005-01-01

BACKGROUND: It is unknown whether further expansion of the Dutch childhood vaccination program with other vaccines will be accepted and whom should be targeted in educational strategies. AIM: To determine attitudes of parents towards possible future vaccinations for their children and the

Cost-effectiveness of programs to eliminate disparities in elderly vaccination rates in the United States.

Science.gov (United States)

Michaelidis, Constantinos I; Zimmerman, Richard K; Nowalk, Mary Patricia; Smith, Kenneth J

2014-07-15

There are disparities in influenza and pneumococcal vaccination rates among elderly minority groups and little guidance as to which intervention or combination of interventions to eliminate these disparities is likely to be most cost-effective. Here, we evaluate the cost-effectiveness of four hypothetical vaccination programs designed to eliminate disparities in elderly vaccination rates and differing in the number of interventions. We developed a Markov model in which we assumed a healthcare system perspective, 10-year vaccination program and lifetime time horizon. The cohort was the combined African-American and Hispanic 65 year-old birth cohort in the United States in 2009. We evaluated five different vaccination strategies: no vaccination program and four vaccination programs that varied from "low intensity" to "very high intensity" based on the number of interventions deployed in each program, their cumulative cost and their cumulative impact on elderly minority influenza and pneumococcal vaccination rates. The very high intensity vaccination program ($24,479/quality-adjusted life year; QALY) was preferred at willingness-to-pay-thresholds of $50,000 and $100,000/QALY and prevented 37,178 influenza cases, 342 influenza deaths, 1,158 invasive pneumococcal disease (IPD) cases and 174 IPD deaths over the birth cohort's lifetime. In one-way sensitivity analyses, the very high intensity program only became cost-prohibitive (>$100,000/QALY) at less likely values for the influenza vaccination rates achieved in year 10 of the high intensity (>73.5%) or very high intensity (eliminate disparities in elderly minority vaccination rates and including four interventions would be cost-effective.

Molecular characterization of Salmonella Paratyphi B dT+ and Salmonella Heidelberg from poultry and retail chicken meat in Colombia by pulsed-field gel electrophoresis

Science.gov (United States)

Salmonella Paratyphi B dT+ variant (also termed Salmonella Java) and Salmonella Heidelberg are human pathogens frequently isolated from poultry. As a step towards implementing the Colombian Integrated Program for Antimicrobial Resistant Surveillance (COIPARS), this study characterized molecular patt...

Safety and immunogenicity of an oral DNA vaccine encoding Sip of Streptococcus agalactiae from Nile tilapia Oreochromis niloticus delivered by live attenuated Salmonella typhimurium.

Science.gov (United States)

Huang, L Y; Wang, K Y; Xiao, D; Chen, D F; Geng, Y; Wang, J; He, Y; Wang, E L; Huang, J L; Xiao, G Y

2014-05-01

Attenuated Salmonella typhimurium SL7207 was used as a carrier for a reconstructed DNA vaccine against Streptococcus agalactiae. A 1.02 kb DNA fragment, encoding for a portion of the surface immunogenic protein (Sip) of S. agalactiae was inserted into pVAX1. The recombinant plasmid pVAX1-sip was transfected in EPC cells to detect the transient expression by an indirect immunofluorescence assay, together with Western blot analysis. The pVAX1-sip was transformed by electroporation into SL7207. The stability of pVAX1-sip into Salmonella was over 90% after 50 generations with antibiotic selection in vitro while remained stable over 80% during 35 generations under antibiotic-free conditions. The LD50 of SL/pVAX1-sip was 1.7 × 10(11) CFU/fish by intragastric administration which indicated a quite low virulence. Tilapias were inoculated orally at 10(8) CFU/fish, the recombinant bacteria were found present in intestinal tract, spleens and livers and eventually eliminated from the tissues 4 weeks after immunization. Fish immunized at 10(7), 10(8) and 10(9) CFU/fish with different immunization times caused various levels of serum antibody and an effective protection against lethal challenge with the wild-type strain S. agalactiae. Integration studies showed that the pVAX1-sip did not integrate with tilapia chromosomes. The DNA vaccine SL/pVAX1-sip was proved to be safe and effective in protecting tilapias against S. agalactiae infection. Copyright © 2014 Elsevier Ltd. All rights reserved.

Cost-effectiveness of a national enterovirus 71 vaccination program in China.

Science.gov (United States)

Wang, Wenjun; Song, Jianwen; Wang, Jingjing; Li, Yaping; Deng, Huiling; Li, Mei; Gao, Ning; Zhai, Song; Dang, Shuangsuo; Zhang, Xin; Jia, Xiaoli

2017-09-01

Enterovirus 71 (EV71) has caused great morbidity, mortality, and use of health service in children younger than five years in China. Vaccines against EV71 have been proved effective and safe by recent phase 3 trials and are now available in China. The purpose of this study was to evaluate the health impact and cost-effectiveness of a national EV71 vaccination program in China. Using Microsoft Excel, a decision model was built to calculate the net clinical and economic outcomes of EV71 vaccination compared with no EV71 vaccination in a birth cohort of 1,000,000 Chinese children followed for five years. Model parameters came from published epidemiology, clinical and cost data. In the base-case, vaccination would annually avert 37,872 cases of hand, foot and mouth disease (HFMD), 2,629 herpangina cases, 72,900 outpatient visits, 6,363 admissions to hospital, 29 deaths, and 945 disability adjusted life years. The break-even price of the vaccine was $5.2/dose. When the price was less than $8.3 or $14.6/dose, the vaccination program would be highly cost-effective or cost-effective, respectively (incremental cost-effectiveness ratio less than or between one to three times China GDP per capita, respectively). In one-way sensitivity analyses, the HFMD incidence was the only influential parameter at the price of $5/dose. Within the price range of current routine vaccines paid by the government, a national EV71 vaccination program would be cost-saving or highly cost-effective to prevent EV71 related morbidity, mortality, and use of health service among children younger than five years in China. Policy makers should consider including EV71 vaccination as part of China's routine childhood immunization schedule.

Salmonella in Liquid Eggs and Other Foods in Fukuoka Prefecture, Japan

Directory of Open Access Journals (Sweden)

Koichi Murakami

2013-01-01

Full Text Available The study aimed to evaluate the prevalence of Salmonella in retail and wholesale foods in Fukuoka Prefecture, Japan. A total of 2,021 samples collected between 1999 and 2010 were tested using a culture method. Samples consisted of liquid eggs (n=30, meat (beef and pork (n=781, offal (n=69, processed meats (n=2, seafood (n=232, processed seafood (dried fish (n=76, vegetables (n=481, processed vegetables (n=87, fruits (n=167, and herbs (n=96 from 574 outlets and wholesale agents in 15 areas (five samples were undocumented regarding outlets. Overall, liquid egg showed significantly (P<0.001 higher frequencies of Salmonella contamination (13.3% than beef (1/423, 0.2% and pork (3/235, 1.3%. Salmonella enterica subsp. enterica serovar Enteritidis, the most common serovar as a human pathogen, were isolated from two liquid egg samples. No Salmonella were isolated from seafood and vegetable-related samples including seed sprouts (n=261. In conclusion, liquid egg is a significant Salmonella vehicle, showing a need to continue the vaccination of chickens to prevent S. Enteritidis contamination in Japanese eggs. Moreover, further study is needed to evaluate Salmonella contamination in seed sprouts with more sampling from retailers there.

Salmonella in liquid eggs and other foods in fukuoka prefecture, Japan.

Science.gov (United States)

Murakami, Koichi; Noda, Tamie; Onozuka, Daisuke; Sera, Nobuyuki

2013-01-01

The study aimed to evaluate the prevalence of Salmonella in retail and wholesale foods in Fukuoka Prefecture, Japan. A total of 2,021 samples collected between 1999 and 2010 were tested using a culture method. Samples consisted of liquid eggs (n = 30), meat (beef and pork) (n = 781), offal (n = 69), processed meats (n = 2), seafood (n = 232), processed seafood (dried fish) (n = 76), vegetables (n = 481), processed vegetables (n = 87), fruits (n = 167), and herbs (n = 96) from 574 outlets and wholesale agents in 15 areas (five samples were undocumented regarding outlets). Overall, liquid egg showed significantly (P < 0.001) higher frequencies of Salmonella contamination (13.3%) than beef (1/423, 0.2%) and pork (3/235, 1.3%). Salmonella enterica subsp. enterica serovar Enteritidis, the most common serovar as a human pathogen, were isolated from two liquid egg samples. No Salmonella were isolated from seafood and vegetable-related samples including seed sprouts (n = 261). In conclusion, liquid egg is a significant Salmonella vehicle, showing a need to continue the vaccination of chickens to prevent S. Enteritidis contamination in Japanese eggs. Moreover, further study is needed to evaluate Salmonella contamination in seed sprouts with more sampling from retailers there.

Modeling salmonella Dublin into the dairy herd simulation model Simherd

DEFF Research Database (Denmark)

Kudahl, Anne Braad

2010-01-01

Infection with Salmonella Dublin in the dairy herd and effects of the infection and relevant control measures are currently being modeled into the dairy herd simulation model called Simherd. The aim is to compare the effects of different control strategies against Salmonella Dublin on both within...... of the simulations will therefore be used for decision support in the national surveillance and eradication program against Salmonella Dublin. Basic structures of the model are programmed and will be presented at the workshop. The model is in a phase of face-validation by a group of Salmonella......-herd- prevalence and economy by simulations. The project Dublin on both within-herd- prevalence and economy by simulations. The project is a part of a larger national project "Salmonella 2007 - 2011" with the main objective to reduce the prevalence of Salmonella Dublin in Danish Dairy herds. Results...

The occurrence of Salmonella spp. in duck eggs on sale at retail or from catering in England.

Science.gov (United States)

Owen, M; Jorgensen, F; Willis, C; McLauchlin, J; Elviss, N; Aird, H; Fox, A; Kaye, M; Lane, C; de Pinna, E

2016-11-01

Since 2010, human salmonellosis outbreaks in the UK have been detected as associated with the consumption of duck eggs. Little data are available on the rate of occurrence of Salmonella in duck eggs. The aim of this study was to investigate the occurrence of Salmonella spp. in duck eggs on sale and from catering in England during 2011, particularly those from small-scale production. All samples were collected independently of human salmonellosis outbreak investigations. Composite samples of 6-10 eggs (shells and contents were examined separately) were examined for the presence of Salmonella spp. using the ISO 6579:2002 method. Salmonella spp. was recovered from two of 145 samples (1·4%). In one sample, Salmonella Typhimurium DT 8 was isolated from the shells while Salm. Typhimurium DT 8 and Salm. Typhimurium DT30 were isolated from the contents. Salmonella Typhimurium DT8 was isolated from the egg shells only in the second contaminated sample. This study provides baseline data for risk assessors, regulators and the food industry and may be helpful in communicating risks associated with the consumption of this product as well as evaluating risk management options to control food safety including vaccination of ducks. Human salmonellosis outbreaks in England and Northern Ireland due to Salmonella enterica serovar Typhimurium definitive phage type (DT) 8 have been identified as associated with the consumption of duck eggs since 2010. This study has shown that Salmonella spp. was detected in 1·4% of ducks egg samples providing baseline data for risk assessors, regulators and the food industry. This may be helpful in communicating risks associated with the consumption of this product as well as evaluating risk management options to control food safety including vaccination of ducks. © 2016 Crown copyright. Letters in Applied Microbiology © 2016 The Society for Applied Microbiology.

Impact of a website based educational program for increasing vaccination coverage among adolescents.

Science.gov (United States)

Esposito, Susanna; Bianchini, Sonia; Tagliabue, Claudia; Umbrello, Giulia; Madini, Barbara; Di Pietro, Giada; Principi, Nicola

2018-04-03

Data regarding the use of technology to improve adolescent knowledge on vaccines are scarce. The main aim of this study was to evaluate whether different web-based educational programmes for adolescents might increase their vaccination coverage. Overall, 917 unvaccinated adolescents (389 males, 42.4%; mean age ± standard deviation, 14.0 ± 2.2 years) were randomized 1:1:1 into the following groups: no intervention (n = 334), website educational program only (n = 281), or website plus face to face lesson (n = 302) groups. The use of the website plus the lesson significantly increased the overall knowledge of various aspects of vaccine-preventable disease and reduced the fear of vaccines (p education of adolescents while considering all of the vaccines recommended for this age group. Our results demonstrate the possibility of increasing vaccination coverage by using a website based educational program with tailored information. However, to be most effective, this program should be supplemented with face-to-face discussions of vaccines at school and at home. Thus, specific education should also include teachers and parents so that they will be prepared to discuss with adolescents what is true and false in the vaccination field.

Analyzing and strengthening the vaccine safety program in Manitoba.

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Montalban, J M; Ogbuneke, C; Hilderman, T

2014-12-04

The emergence of a novel influenza A virus in 2009 and the rapid introduction of new pandemic vaccines prompted an analysis of the current state of the adverse events following immunization (AEFI) surveillance response in several provinces. To highlight aspects of the situational analysis of the Manitoba Health, Healthy Living and Seniors (MHHLS's) AEFI surveillance system and to demonstrate how common business techniques could be usefully applied to a provincial vaccine safety monitoring program. Situational analysis of the AEFI surveillance system in Manitoba was developed through a strengths-weaknesses-opportunities-threats (SWOT) analysis and informed by the National Immunization Strategy vaccine safety priorities. Strategy formulation was developed by applying the threats-opportunities-weaknesses-strengths (TOWS) matrix. Thirteen strategies were formulated that use strengths to either take advantage of opportunities or avoid threats, that exploit opportunities to overcome weaknesses, or that rectify weaknesses to circumvent threats. These strategies entailed the development of various tools and resources, most of which are either actively underway or completed. The SWOT analysis and the TOWS matrix enabled MHHLS to enhance the capacity of its vaccine safety program.

Salmonella

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... Compartir Find out about Salmonella infections linked to Kellogg’s Honey Smacks Cereal Find out about Salmonella infections ... Outbreaks Multistate Outbreak of Salmonella Infections Linked to Kellogg’s Honey Smacks Cereal Multistate Outbreak of Salmonella Adelaide ...

Oral immunization using HgbA in a recombinant chancroid vaccine delivered by attenuated Salmonella typhimurium SL3261 in the temperature-dependent rabbit model.

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Breau, Cathy; Cameron, D William; Desjardins, Marc; Lee, B Craig

2012-01-31

Chancroid, a sexually transmitted genital ulcer disease caused by the Gram-negative bacterium Haemophilus ducreyi, facilitates the acquisition and transmission of HIV. An effective vaccine against chancroid has not been developed. In this preliminary study, the gene encoding the H. ducreyi outer membrane hemoglobin receptor HgbA was cloned into the plasmid pTETnir15. The recombinant construct was introduced into the attenuated Salmonella typhimurium SL3261 strain and stable expression was induced in vitro under anaerobic conditions. The vaccine strain was delivered into the temperature-dependent rabbit model of chancroid by intragastric immunization as a single dose, or as three doses administered at two-weekly intervals. No specific antibody to HgbA was elicited after either dose schedule. Although the plasmid vector survived in vivo passage for up to 15 days following single oral challenge, HgbA expression was restricted to plasmid isolates recovered one day after immunization. Rabbits inoculated with the 3-dose booster regimen achieved no protective immunity from homologous challenge. These results emphasize that refinements in plasmid design to enhance a durable heterologous protein expression are necessary for the development of a live oral vaccine against chancroid. Copyright © 2011 Elsevier B.V. All rights reserved.

Live attenuated S. Typhimurium vaccine with improved safety in immuno-compromised mice.

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Balamurugan Periaswamy

Full Text Available Live attenuated vaccines are of great value for preventing infectious diseases. They represent a delicate compromise between sufficient colonization-mediated adaptive immunity and minimizing the risk for infection by the vaccine strain itself. Immune defects can predispose to vaccine strain infections. It has remained unclear whether vaccine safety could be improved via mutations attenuating a vaccine in immune-deficient individuals without compromising the vaccine's performance in the normal host. We have addressed this hypothesis using a mouse model for Salmonella diarrhea and a live attenuated Salmonella Typhimurium strain (ssaV. Vaccination with this strain elicited protective immunity in wild type mice, but a fatal systemic infection in immune-deficient cybb(-/-nos2(-/- animals lacking NADPH oxidase and inducible NO synthase. In cybb(-/-nos2(-/- mice, we analyzed the attenuation of 35 ssaV strains carrying one additional mutation each. One strain, Z234 (ssaV SL1344_3093, was >1000-fold attenuated in cybb(-/-nos2(-/- mice and ≈100 fold attenuated in tnfr1(-/- animals. However, in wt mice, Z234 was as efficient as ssaV with respect to host colonization and the elicitation of a protective, O-antigen specific mucosal secretory IgA (sIgA response. These data suggest that it is possible to engineer live attenuated vaccines which are specifically attenuated in immuno-compromised hosts. This might help to improve vaccine safety.

Investigating Stakeholder Attitudes and Opinions on School-Based Human Papillomavirus Vaccination Programs

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Nodulman, Jessica A.; Starling, Randall; Kong, Alberta S.; Buller, David B.; Wheeler, Cosette M.; Woodall, W. Gill

2015-01-01

Background: In several countries worldwide, school-based human papillomavirus (HPV) vaccination programs have been successful; however, little research has explored US stakeholders' acceptance toward school-based HPV vaccination programs. Methods: A total of 13 focus groups and 12 key informant interviews (N?=?117; 85% females; 66% racial/ethnic…

Methods and challenges for the health impact assessment of vaccination programs in Latin America

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Ana Marli Christovam Sartori

2015-01-01

Full Text Available ABSTRACT OBJECTIVE To describe methods and challenges faced in the health impact assessment of vaccination programs, focusing on the pneumococcal conjugate and rotavirus vaccines in Latin America and the Caribbean. METHODS For this narrative review, we searched for the terms "rotavirus", "pneumococcal", "conjugate vaccine", "vaccination", "program", and "impact" in the databases Medline and LILACS. The search was extended to the grey literature in Google Scholar. No limits were defined for publication year. Original articles on the health impact assessment of pneumococcal and rotavirus vaccination programs in Latin America and the Caribbean in English, Spanish or Portuguese were included. RESULTS We identified 207 articles. After removing duplicates and assessing eligibility, we reviewed 33 studies, 25 focusing on rotavirus and eight on pneumococcal vaccination programs. The most frequent studies were ecological, with time series analysis or comparing pre- and post-vaccination periods. The main data sources were: health information systems; population-, sentinel- or laboratory-based surveillance systems; statistics reports; and medical records from one or few health care services. Few studies used primary data. Hospitalization and death were the main outcomes assessed. CONCLUSIONS Over the last years, a significant number of health impact assessments of pneumococcal and rotavirus vaccination programs have been conducted in Latin America and the Caribbean. These studies were carried out few years after the programs were implemented, meet the basic methodological requirements and suggest positive health impact. Future assessments should consider methodological issues and challenges arisen in these first studies conducted in the region.

Factors Associated with Salmonella Prevalence in U.S. Swine Grower-Finisher Operations, 2012.

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Bjork, Kathe E; Fields, Victoria; Garber, Lindsey P; Kopral, Christine A

2018-05-15

Nontyphoidal Salmonella is an important foodborne pathogen with diverse serotypes occurring in animal and human populations. The prevalence of the organism on swine farms has been associated with numerous risk factors, and although there are strong veterinary public health controls for preventing Salmonella from entering food, there remains interest in eradicating or controlling the organism in the preharvest environment. In this study, using data collected via the U.S. Department of Agriculture (USDA) National Animal Health Monitoring System Swine 2012 study, we describe nontyphoidal Salmonella and specific serotype prevalence on U.S. grower-finisher swine operations and investigate associations between Salmonella detection and numerous factors via multiple correspondence analysis (MCA) and regression analysis. MCA plots, complementary to univariate analyses, display relationships between covariates and Salmonella detection at the farm level. In the univariate analysis, Salmonella detection varied with feed characteristics and farm management practices, reports of diseases on farms and vaccinations administered, and administration of certain antimicrobials. Results from the univariate analysis reinforce the importance of biosecurity in managing diseases and pathogens such as Salmonella on farms. All multivariable regression models for the likelihood of Salmonella detection were strongly affected by multicollinearity among variables, and only one variable, pelleted feed preparation, remained in the final model. The study was limited by its cross-sectional nature, timelines of data collection, and reliance on operator-reported data via a convenience sample.

Attenuated Salmonella enterica serovar Typhi and Shigella flexneri 2a strains mucosally deliver DNA vaccines encoding measles virus hemagglutinin, inducing specific immune responses and protection in cotton rats.

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Pasetti, Marcela F; Barry, Eileen M; Losonsky, Genevieve; Singh, Mahender; Medina-Moreno, Sandra M; Polo, John M; Ulmer, Jeffrey; Robinson, Harriet; Sztein, Marcelo B; Levine, Myron M

2003-05-01

Measles remains a leading cause of child mortality in developing countries. Residual maternal measles antibodies and immunologic immaturity dampen immunogenicity of the current vaccine in young infants. Because cotton rat respiratory tract is susceptible to measles virus (MV) replication after intranasal (i.n.) challenge, this model can be used to assess the efficacy of MV vaccines. Pursuing a new measles vaccine strategy that might be effective in young infants, we used attenuated Salmonella enterica serovar Typhi CVD 908-htrA and Shigella flexneri 2a CVD 1208 vaccines to deliver mucosally to cotton rats eukaryotic expression plasmid pGA3-mH and Sindbis virus-based DNA replicon pMSIN-H encoding MV hemagglutinin (H). The initial i.n. dose-response with bacterial vectors alone identified a well-tolerated dosage (1 x 10(9) to 7 x 10(9) CFU) and a volume (20 micro l) that elicited strong antivector immune responses. Animals immunized i.n. on days 0, 28, and 76 with bacterial vectors carrying DNA plasmids encoding MV H or immunized parenterally with these naked DNA vaccine plasmids developed MV plaque reduction neutralizing antibodies and proliferative responses against MV antigens. In a subsequent experiment of identical design, cotton rats were challenged with wild-type MV 1 month after the third dose of vaccine or placebo. MV titers were significantly reduced in lung tissue of animals immunized with MV DNA vaccines delivered either via bacterial live vectors or parenterally. Since attenuated serovar Typhi and S. flexneri can deliver measles DNA vaccines mucosally in cotton rats, inducing measles immune responses (including neutralizing antibodies) and protection, boosting strategies can now be evaluated in animals primed with MV DNA vaccines.

[Meningococcal C conjugate vaccine: Impact of a vaccination program and long-term effectiveness in Navarra, Spain, 2000-2014].

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Morales, Desirée; García-Cenoz, Manuel; Moreno, Laura; Bernaola, Enrique; Barricarte, Aurelio; Castilla, Jesús

2016-12-01

Since 2000, when the meningococcal serogroupC conjugate vaccine (MenCC) was introduced in the childhood immunization schedule in Spain, several changes in the schedule and catch-up campaigns have been performed. We aim to estimate the impact and effectiveness of this vaccine in Navarra up to 2014. The impact of the vaccination program was analysed by comparing incidence, mortality and lethality rates of disease before (1995-1999) and after (2004-2014) the introduction of the MenCC. Vaccine effectiveness was estimated using the screening method (Farrington) and the indirect cohort method (Broome). Data on cases were obtained from the active surveillance of meningococcal disease. During 1995-1999 the mean annual incidence of meningococcalC disease was 1.32 per 100,000, and 7.18 per 100,000 in children younger than 15years. The fall of meningococcalC disease incidence was significant in cohorts targeted for vaccination from the beginning and progressive in the general population. No cases were reported between 2011 and 2014. The estimated vaccine effectiveness was 96% by the screening method, and 99% by the indirect cohort method. The MenCC vaccination program has been successful in decreasing the incidence rate of serogroupC meningococcal disease in Navarra, and schedule changes have maintained high vaccine effectiveness throughout the study period. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Assessing the Importance of Domestic Vaccine Manufacturing Centers: An Overview of Immunization Programs, Vaccine Manufacture, and Distribution

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Emma Rey-Jurado

2018-01-01

Full Text Available Vaccines have significantly reduced the detrimental effects of numerous human infectious diseases worldwide, helped to reduce drastically child mortality rates and even achieved eradication of major pathogens, such as smallpox. These achievements have been possible due to a dedicated effort for vaccine research and development, as well as an effective transfer of these vaccines to public health care systems globally. Either public or private institutions have committed to developing and manufacturing vaccines for local or international population supply. However, current vaccine manufacturers worldwide might not be able to guarantee sufficient vaccine supplies for all nations when epidemics or pandemics events could take place. Currently, different countries produce their own vaccine supplies under Good Manufacturing Practices, which include the USA, Canada, China, India, some nations in Europe and South America, such as Germany, the Netherlands, Italy, France, Argentina, and Brazil, respectively. Here, we discuss some of the vaccine programs and manufacturing capacities, comparing the current models of vaccine management between industrialized and developing countries. Because local vaccine production undoubtedly provides significant benefits for the respective population, the manufacture capacity of these prophylactic products should be included in every country as a matter of national safety.

Assessing the Importance of Domestic Vaccine Manufacturing Centers: An Overview of Immunization Programs, Vaccine Manufacture, and Distribution.

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Rey-Jurado, Emma; Tapia, Felipe; Muñoz-Durango, Natalia; Lay, Margarita K; Carreño, Leandro J; Riedel, Claudia A; Bueno, Susan M; Genzel, Yvonne; Kalergis, Alexis M

2018-01-01

Vaccines have significantly reduced the detrimental effects of numerous human infectious diseases worldwide, helped to reduce drastically child mortality rates and even achieved eradication of major pathogens, such as smallpox. These achievements have been possible due to a dedicated effort for vaccine research and development, as well as an effective transfer of these vaccines to public health care systems globally. Either public or private institutions have committed to developing and manufacturing vaccines for local or international population supply. However, current vaccine manufacturers worldwide might not be able to guarantee sufficient vaccine supplies for all nations when epidemics or pandemics events could take place. Currently, different countries produce their own vaccine supplies under Good Manufacturing Practices, which include the USA, Canada, China, India, some nations in Europe and South America, such as Germany, the Netherlands, Italy, France, Argentina, and Brazil, respectively. Here, we discuss some of the vaccine programs and manufacturing capacities, comparing the current models of vaccine management between industrialized and developing countries. Because local vaccine production undoubtedly provides significant benefits for the respective population, the manufacture capacity of these prophylactic products should be included in every country as a matter of national safety.

A population-based evaluation of a publicly funded, school-based HPV vaccine program in British Columbia, Canada: parental factors associated with HPV vaccine receipt.

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Ogilvie, Gina; Anderson, Maureen; Marra, Fawziah; McNeil, Shelly; Pielak, Karen; Dawar, Meena; McIvor, Marilyn; Ehlen, Thomas; Dobson, Simon; Money, Deborah; Patrick, David M; Naus, Monika

2010-05-04

Information on factors that influence parental decisions for actual human papillomavirus (HPV) vaccine receipt in publicly funded, school-based HPV vaccine programs for girls is limited. We report on the level of uptake of the first dose of the HPV vaccine, and determine parental factors associated with receipt of the HPV vaccine, in a publicly funded school-based HPV vaccine program in British Columbia, Canada. All parents of girls enrolled in grade 6 during the academic year of September 2008-June 2009 in the province of British Columbia were eligible to participate. Eligible households identified through the provincial public health information system were randomly selected and those who consented completed a validated survey exploring factors associated with HPV vaccine uptake. Bivariate and multivariate analyses were conducted to calculate adjusted odds ratios to identify the factors that were associated with parents' decision to vaccinate their daughter(s) against HPV. 2,025 parents agreed to complete the survey, and 65.1% (95% confidence interval [CI] 63.1-67.1) of parents in the survey reported that their daughters received the first dose of the HPV vaccine. In the same school-based vaccine program, 88.4% (95% CI 87.1-89.7) consented to the hepatitis B vaccine, and 86.5% (95% CI 85.1-87.9) consented to the meningococcal C vaccine. The main reasons for having a daughter receive the HPV vaccine were the effectiveness of the vaccine (47.9%), advice from a physician (8.7%), and concerns about daughter's health (8.4%). The main reasons for not having a daughter receive the HPV vaccine were concerns about HPV vaccine safety (29.2%), preference to wait until the daughter is older (15.6%), and not enough information to make an informed decision (12.6%). In multivariate analysis, overall attitudes to vaccines, the impact of the HPV vaccine on sexual practices, and childhood vaccine history were predictive of parents having a daughter receive the HPV vaccine in a

A population-based evaluation of a publicly funded, school-based HPV vaccine program in British Columbia, Canada: parental factors associated with HPV vaccine receipt.

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Gina Ogilvie

2010-05-01

Full Text Available BACKGROUND: Information on factors that influence parental decisions for actual human papillomavirus (HPV vaccine receipt in publicly funded, school-based HPV vaccine programs for girls is limited. We report on the level of uptake of the first dose of the HPV vaccine, and determine parental factors associated with receipt of the HPV vaccine, in a publicly funded school-based HPV vaccine program in British Columbia, Canada. METHODS AND FINDINGS: All parents of girls enrolled in grade 6 during the academic year of September 2008-June 2009 in the province of British Columbia were eligible to participate. Eligible households identified through the provincial public health information system were randomly selected and those who consented completed a validated survey exploring factors associated with HPV vaccine uptake. Bivariate and multivariate analyses were conducted to calculate adjusted odds ratios to identify the factors that were associated with parents' decision to vaccinate their daughter(s against HPV. 2,025 parents agreed to complete the survey, and 65.1% (95% confidence interval [CI] 63.1-67.1 of parents in the survey reported that their daughters received the first dose of the HPV vaccine. In the same school-based vaccine program, 88.4% (95% CI 87.1-89.7 consented to the hepatitis B vaccine, and 86.5% (95% CI 85.1-87.9 consented to the meningococcal C vaccine. The main reasons for having a daughter receive the HPV vaccine were the effectiveness of the vaccine (47.9%, advice from a physician (8.7%, and concerns about daughter's health (8.4%. The main reasons for not having a daughter receive the HPV vaccine were concerns about HPV vaccine safety (29.2%, preference to wait until the daughter is older (15.6%, and not enough information to make an informed decision (12.6%. In multivariate analysis, overall attitudes to vaccines, the impact of the HPV vaccine on sexual practices, and childhood vaccine history were predictive of parents having

Analyzing and strengthening the vaccine safety program in Manitoba

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Montalban, JM; Ogbuneke, C; Hilderman, T

2014-01-01

Background: The emergence of a novel influenza A virus in 2009 and the rapid introduction of new pandemic vaccines prompted an analysis of the current state of the adverse events following immunization (AEFI) surveillance response in several provinces. Objectives To highlight aspects of the situational analysis of the Manitoba Health, Healthy Living and Seniors (MHHLS’s) AEFI surveillance system and to demonstrate how common business techniques could be usefully applied to a provincial vaccine safety monitoring program. Method Situational analysis of the AEFI surveillance system in Manitoba was developed through a strengths-weaknesses-opportunities-threats (SWOT) analysis and informed by the National Immunization Strategy vaccine safety priorities. Strategy formulation was developed by applying the threats-opportunities-weaknesses-strengths (TOWS) matrix. Results Thirteen strategies were formulated that use strengths to either take advantage of opportunities or avoid threats, that exploit opportunities to overcome weaknesses, or that rectify weaknesses to circumvent threats. These strategies entailed the development of various tools and resources, most of which are either actively underway or completed. Conclusion The SWOT analysis and the TOWS matrix enabled MHHLS to enhance the capacity of its vaccine safety program. PMID:29769910

Too Late to Vaccinate? The Incremental Benefits and Cost-effectiveness of a Delayed Catch-up Program Using the 4-Valent Human Papillomavirus Vaccine in Norway

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Burger, Emily A.; Sy, Stephen; Nygård, Mari; Kristiansen, Ivar S.; Kim, Jane J.

2015-01-01

Background Human papillomavirus (HPV) vaccines are ideally administered before HPV exposure; therefore, catch-up programs for girls past adolescence have not been readily funded. We evaluated the benefits and cost-effectiveness of a delayed, 1-year female catch-up vaccination program in Norway. Methods We calibrated a dynamic HPV transmission model to Norwegian data and projected the costs and benefits associated with 8 HPV-related conditions while varying the upper vaccination age limit to 20, 22, 24, or 26 years. We explored the impact of vaccine protection in women with prior vaccine-targeted HPV infections, vaccine cost, coverage, and natural- and vaccine-induced immunity. Results The incremental benefits and cost-effectiveness decreased as the upper age limit for catch-up increased. Assuming a vaccine cost of $150/dose, vaccination up to age 20 years remained below Norway's willingness-to-pay threshold (approximately $83 000/quality-adjusted life year gained); extension to age 22 years was cost-effective at a lower cost per dose ($50–$75). At high levels of vaccine protection in women with prior HPV exposure, vaccinating up to age 26 years was cost-effective. Results were stable with lower coverage. Conclusions HPV vaccination catch-up programs, 5 years after routine implementation, may be warranted; however, even at low vaccine cost per dose, the cost-effectiveness of vaccinating beyond age 22 years remains uncertain. PMID:25057044

Cost-Effectiveness of a Program to Eliminate Disparities in Pneumococcal Vaccination Rates in Elderly Minority Populations: An Exploratory Analysis

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Michaelidis, Constantinos I.; Zimmerman, Richard K.; Nowalk, Mary Patricia; Smith, Kenneth J.

2013-01-01

Objective Invasive pneumococcal disease is a major cause of preventable morbidity and mortality in the United States, particularly among the elderly (>65 years). There are large racial disparities in pneumococcal vaccination rates in this population. Here, we estimate the cost-effectiveness of a hypothetical national vaccination intervention program designed to eliminate racial disparities in pneumococcal vaccination in the elderly. Methods In an exploratory analysis, a Markov decision-analysis model was developed, taking a societal perspective and assuming a 1-year cycle length, 10-year vaccination program duration, and lifetime time horizon. In the base-case analysis, it was conservatively assumed that vaccination program promotion costs were $10 per targeted minority elder per year, regardless of prior vaccination status and resulted in the elderly African American and Hispanic pneumococcal vaccination rate matching the elderly Caucasian vaccination rate (65%) in year 10 of the program. Results The incremental cost-effectiveness of the vaccination program relative to no program was $45,161 per quality-adjusted life-year gained in the base-case analysis. In probabilistic sensitivity analyses, the likelihood of the vaccination program being cost-effective at willingness-to-pay thresholds of $50,000 and $100,000 per quality-adjusted life-year gained was 64% and 100%, respectively. Conclusions In a conservative analysis biased against the vaccination program, a national vaccination intervention program to ameliorate racial disparities in pneumococcal vaccination would be cost-effective. PMID:23538183

National Vaccine Injury Compensation Program (VICP) -Data & Statistics

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U.S. Department of Health & Human Services — The VICP program publishes a summary PDF report with several data tables: Number of Petitions Filed by Adjudication Categories by Alleged Vaccine, including # of...

Surface display of Salmonella epitopes in Escherichia coli and Staphylococcus carnosus.

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Nhan, Nguyen Thanh; Gonzalez de Valdivia, Ernesto; Gustavsson, Martin; Hai, Truong Nam; Larsson, Gen

2011-04-11

Salmonella enterica serotype Enteritidis (SE) is considered to be one of the most potent pathogenic Salmonella serotypes causing food-borne disease in humans. Since a live bacterial vaccine based on surface display of antigens has many advantages over traditional vaccines, we have studied the surface display of the SE antigenic proteins, H:gm and SefA in Escherichia coli by the β-autotransporter system, AIDA. This procedure was compared to protein translocation in Staphylococcus carnosus, using a staphylococci hybrid vector earlier developed for surface display of other vaccine epitopes. Both SefA and H:gm were translocated to the outer membrane in Escherichia coli. SefA was expressed to full length but H:gm was shorter than expected, probably due to a proteolytic cleavage of the N-terminal during passage either through the periplasm or over the membrane. FACS analysis confirmed that SefA was facing the extracellular environment, but this could not be conclusively established for H:gm since the N-terminal detection tag (His6) was cleaved off. Polyclonal salmonella antibodies confirmed the sustained antibody-antigen binding towards both proteins. The surface expression data from Staphylococcus carnosus suggested that the H:gm and SefA proteins were transported to the cell wall since the detection marker was displayed by FACS analysis. Apart from the accumulated knowledge and the existence of a wealth of equipment and techniques, the results indicate the selection of E. coli for further studies for surface expression of salmonella antigens. Surface expression of the full length protein facing the cell environment was positively proven by standard analysis, and the FACS signal comparison to expression in Staphylococcus carnosus shows that the distribution of the surface protein on each cell was comparatively very narrow in E. coli, the E. coli outer membrane molecules can serve as an adjuvant for the surface antigenic proteins and multimeric forms of the SefA protein

Can opportunities be enhanced for vaccinating children in home visiting programs? A population-based cohort study.

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Isaac, Michael R; Chartier, Mariette; Brownell, Marni; Chateau, Dan; Nickel, Nathan C; Martens, Patricia; Katz, Alan; Sarkar, Joykrishna; Hu, Milton; Burland, Elaine; Goh, ChunYan; Taylor, Carole

2015-07-07

Home visiting programs focused on improving early childhood environments are commonplace in North America. A goal of many of these programs is to improve the overall health of children, including promotion of age appropriate vaccination. In this study, population-based data are used to examine the effect of a home visiting program on vaccination rates in children. Home visiting program data from Manitoba, Canada were linked to several databases, including a provincial vaccination registry to examine vaccination rates in a cohort of children born between 2003 and 2009. Propensity score weights were used to balance potential confounders between a group of children enrolled in the program (n = 4,562) and those who were eligible but not enrolled (n = 5,184). Complete and partial vaccination rates for one and two year old children were compared between groups, including stratification into area-level income quintiles. Complete vaccination rates from birth to age 1 and 2 were higher for those enrolled in the Families First program [Average Treatment Effect Risk Ratio (ATE RR) 1.06 (95 % CI 1.03-1.08) and 1.10 (95 % CI 1.05-1.15) respectively]. No significant differences were found between groups having at least one vaccination at age 1 or 2 [ATE RR 1.01 (95 % CI 1.00-1.02) and 1.00 (95 % CI 1.00-1.01) respectively). The interaction between program and income quintiles was not statistically significant suggesting that the program effect did not differ by income quintile. Home visiting programs have the potential to increase vaccination rates for children enrolled, despite limited program content directed towards this end. Evidence-based program enhancements have the potential to increase these rates further, however more research is needed to inform policy makers of optimal approaches in this regard, especially with respect to cost-effectiveness.

A school-based human papillomavirus vaccination program in barretos, Brazil: final results of a demonstrative study.

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José Humberto Tavares Guerreiro Fregnani

Full Text Available The implementation of a public HPV vaccination program in several developing countries, especially in Latin America, is a great challenge for health care specialists.To evaluate the uptake and the three-dose completion rates of a school-based HPV vaccination program in Barretos (Brazil.THE STUDY INCLUDED GIRLS WHO WERE ENROLLED IN PUBLIC AND PRIVATE SCHOOLS AND WHO REGULARLY ATTENDED THE SIXTH AND SEVENTH GRADES OF ELEMENTARY SCHOOL (MEAN AGE: 11.9 years. A meeting with the parents or guardians occurred approximately one week before the vaccination in order to explain the project and clarify the doubts. The quadrivalent vaccine was administered using the same schedule as in the product package (0-2-6 months. The school visits for regular vaccination occurred on previously scheduled dates. The vaccine was also made available at Barretos Cancer Hospital for the girls who could not be vaccinated on the day when the team visited the school.Among the potential candidates for vaccination (n = 1,574, the parents or guardians of 1,513 girls (96.1% responded to the invitation to participate in the study. A total of 1,389 parents or guardians agreed to participate in the program (acceptance rate = 91.8%. The main reason for refusing to participate in the vaccination program was fear of adverse events. The vaccine uptake rates for the first, second, and third doses were 87.5%, 86.3% and 85.0%, respectively. The three-dose completion rate was 97.2%.This demonstrative study achieved high rates of vaccination uptake and completion of three vaccine doses in children 10-16 years old from Brazil. The feasibility and success of an HPV vaccination program for adolescents in a developing country may depend on the integration between the public health and schooling systems.

Use of a recombinant Salmonella enterica serovar Typhimurium strain expressing C-Raf for protection against C-Raf induced lung adenoma in mice

International Nuclear Information System (INIS)

Gentschev, Ivaylo; Fensterle, Joachim; Schmidt, Andreas; Potapenko, Tamara; Troppmair, Jakob; Goebel, Werner; Rapp, Ulf R

2005-01-01

Serine-threonine kinases of the Raf family (A-Raf, B-Raf, C-Raf) are central players in cellular signal transduction, and thus often causally involved in the development of cancer when mutated or over-expressed. Therefore these proteins are potential targets for immunotherapy and a possible basis for vaccine development against tumors. In this study we analyzed the functionality of a new live C-Raf vaccine based on an attenuated Salmonella enterica serovar Typhimurium aroA strain in two Raf dependent lung tumor mouse models. The antigen C-Raf has been fused to the C-terminal secretion signal of Escherichia coli α-hemolysin and expressed in secreted form by an attenuated aroA Salmonella enterica serovar Typhimurium strain via the α-hemolysin secretion pathway. The effect of the immunization with this recombinant C-Raf strain on wild-type C57BL/6 or lung tumor bearing transgenic BxB mice was analyzed using western blot and FACS analysis as well as specific tumor growth assays. C-Raf antigen was successfully expressed in secreted form by an attenuated Salmonella enterica serovar Typhimurium aroA strain using the E. coli hemolysin secretion system. Immunization of wild-type C57BL/6 or tumor bearing mice provoked specific C-Raf antibody and T-cell responses. Most importantly, the vaccine strain significantly reduced tumor growth in two transgenic mouse models of Raf oncogene-induced lung adenomas. The combination of the C-Raf antigen, hemolysin secretion system and Salmonella enterica serovar Typhimurium could form the basis for a new generation of live bacterial vaccines for the treatment of Raf dependent human malignancies

Salmonella serotype distribution in the Dutch broiler supply chain.

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van Asselt, E D; Thissen, J T N M; van der Fels-Klerx, H J

2009-12-01

Salmonella serotype distribution can give insight in contamination routes and persistence along a production chain. Therefore, it is important to determine not only Salmonella prevalence but also to specify the serotypes involved at the different stages of the supply chain. For this purpose, data from a national monitoring program in the Netherlands were used to estimate the serotype distribution and to determine whether this distribution differs for the available sampling points in the broiler supply chain. Data covered the period from 2002 to 2005, all slaughterhouses (n = 22), and the following 6 sampling points: departure from hatchery, arrival at the farm, departure from the farm, arrival at the slaughterhouse, departure from the slaughterhouse, and end of processing. Furthermore, retail data for 2005 were used for comparison with slaughterhouse data. The following serotypes were followed throughout the chain: Salmonella Enteritidis, Salmonella Typhimurium, Salmonella Paratyphi B var. Java (Salmonella Java), Salmonella Infantis, Salmonella Virchow, and Salmonella Mbandaka. Results showed that serotype distribution varied significantly throughout the supply chain (P supply chain up to the retail phase.

Is a HIV vaccine a viable option and at what price? An economic evaluation of adding HIV vaccination into existing prevention programs in Thailand

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Peerapatanapokin Wiwat

2011-07-01

Full Text Available Abstract Background This study aims to determine the maximum price at which HIV vaccination is cost-effective in the Thai healthcare setting. It also aims to identify the relative importance of vaccine characteristics and risk behavior changes among vaccine recipients to determine how they affect this cost-effectiveness. Methods A semi-Markov model was developed to estimate the costs and health outcomes of HIV prevention programs combined with HIV vaccination in comparison to the existing HIV prevention programs without vaccination. The estimation was based on a lifetime horizon period (99 years and used the government perspective. The analysis focused on both the general population and specific high-risk population groups. The maximum price of cost-effective vaccination was defined by using threshold analysis; one-way and probabilistic sensitivity analyses were performed. The study employed an expected value of perfect information (EVPI analysis to determine the relative importance of parameters and to prioritize future studies. Results The most expensive HIV vaccination which is cost-effective when given to the general population was 12,000 Thai baht (US$1 = 34 Thai baht in 2009. This vaccination came with 70% vaccine efficacy and lifetime protection as long as risk behavior was unchanged post-vaccination. The vaccine would be considered cost-ineffective at any price if it demonstrated low efficacy (30% and if post-vaccination risk behavior increased by 10% or more, especially among the high-risk population groups. The incremental cost-effectiveness ratios were the most sensitive to change in post-vaccination risk behavior, followed by vaccine efficacy and duration of protection. The EVPI indicated the need to quantify vaccine efficacy, changed post-vaccination risk behavior, and the costs of vaccination programs. Conclusions The approach used in this study differentiated it from other economic evaluations and can be applied for the economic

Is a HIV vaccine a viable option and at what price? An economic evaluation of adding HIV vaccination into existing prevention programs in Thailand.

Science.gov (United States)

Leelahavarong, Pattara; Teerawattananon, Yot; Werayingyong, Pitsaphun; Akaleephan, Chutima; Premsri, Nakorn; Namwat, Chawetsan; Peerapatanapokin, Wiwat; Tangcharoensathien, Viroj

2011-07-05

This study aims to determine the maximum price at which HIV vaccination is cost-effective in the Thai healthcare setting. It also aims to identify the relative importance of vaccine characteristics and risk behavior changes among vaccine recipients to determine how they affect this cost-effectiveness. A semi-Markov model was developed to estimate the costs and health outcomes of HIV prevention programs combined with HIV vaccination in comparison to the existing HIV prevention programs without vaccination. The estimation was based on a lifetime horizon period (99 years) and used the government perspective. The analysis focused on both the general population and specific high-risk population groups. The maximum price of cost-effective vaccination was defined by using threshold analysis; one-way and probabilistic sensitivity analyses were performed. The study employed an expected value of perfect information (EVPI) analysis to determine the relative importance of parameters and to prioritize future studies. The most expensive HIV vaccination which is cost-effective when given to the general population was 12,000 Thai baht (US$1 = 34 Thai baht in 2009). This vaccination came with 70% vaccine efficacy and lifetime protection as long as risk behavior was unchanged post-vaccination. The vaccine would be considered cost-ineffective at any price if it demonstrated low efficacy (30%) and if post-vaccination risk behavior increased by 10% or more, especially among the high-risk population groups. The incremental cost-effectiveness ratios were the most sensitive to change in post-vaccination risk behavior, followed by vaccine efficacy and duration of protection. The EVPI indicated the need to quantify vaccine efficacy, changed post-vaccination risk behavior, and the costs of vaccination programs. The approach used in this study differentiated it from other economic evaluations and can be applied for the economic evaluation of other health interventions not available in

Too late to vaccinate? The incremental benefits and cost-effectiveness of a delayed catch-up program using the 4-valent human papillomavirus vaccine in Norway.

Science.gov (United States)

Burger, Emily A; Sy, Stephen; Nygård, Mari; Kristiansen, Ivar S; Kim, Jane J

2015-01-15

Human papillomavirus (HPV) vaccines are ideally administered before HPV exposure; therefore, catch-up programs for girls past adolescence have not been readily funded. We evaluated the benefits and cost-effectiveness of a delayed, 1-year female catch-up vaccination program in Norway. We calibrated a dynamic HPV transmission model to Norwegian data and projected the costs and benefits associated with 8 HPV-related conditions while varying the upper vaccination age limit to 20, 22, 24, or 26 years. We explored the impact of vaccine protection in women with prior vaccine-targeted HPV infections, vaccine cost, coverage, and natural- and vaccine-induced immunity. The incremental benefits and cost-effectiveness decreased as the upper age limit for catch-up increased. Assuming a vaccine cost of $150/dose, vaccination up to age 20 years remained below Norway's willingness-to-pay threshold (approximately $83 000/quality-adjusted life year gained); extension to age 22 years was cost-effective at a lower cost per dose ($50-$75). At high levels of vaccine protection in women with prior HPV exposure, vaccinating up to age 26 years was cost-effective. Results were stable with lower coverage. HPV vaccination catch-up programs, 5 years after routine implementation, may be warranted; however, even at low vaccine cost per dose, the cost-effectiveness of vaccinating beyond age 22 years remains uncertain. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Diagnosis of Salmonella Enteritidis Infection in Broiler Chickens ...

African Journals Online (AJOL)

Diagnosis of Salmonella Enteritidis Infection in Broiler Chickens Using Elisa. ES Soliman, E Taha, WS Abdella, C KilPatrick, AN Wise, MAA Sobieh, PG Reddy. Abstract. The program for the eradication of Salmonella Enteritidis from chickens was based on bacteriological examination of breeding flocks. There is a great need ...

Evaluation of Mexico's Universal Vaccination Program.

Science.gov (United States)

1998-04-01

This article summarizes findings from an evaluation of Mexico's Universal Vaccination Program during 1990-97, the progress achieved, the lessons learned, and objectives under decentralization. The evaluation assessed the cold chain and logistics systems, and the feasibility of vaccine production within Gerencia General de Biologicos y Reactivos. In 1996, 97% of children aged 1-4 years completed the full immunization schedule. Over the past 7 years, the incidence of preventable diseases declined. There were no poliomyelitis cases in the prior 7 years, no diphtheria cases in the prior 6 years, and a gradual decline in morbidity due to measles in the prior 5 years. Several government sectors are giving high priority to vaccination activities. Sufficient resources have been allocated for immunization. The government is planning on adding new vaccines that would benefit the adult population and/or prevent congenital defects. There is close coordination within institutions of the National Health System and with other public health organizations, such as PAHO and UNICEF. It is recommended that the central government perform high quality epidemiological surveillance and improve rapid analysis capacity, especially at the local and regional levels. Improvement is needed in the reporting capacity at the local level, to feed recent data to the central level in a timely fashion, and to use analysis to improve operations. Epidemiological training is needed at the operations level, as is private sector involvement at all levels. Underreporting of morbidity occurs. Regionalization must be monitored to ensure maximizing of resources.

Immunization-Safety Monitoring Systems for the 2009 H1N1 Monovalent Influenza Vaccination Program

NARCIS (Netherlands)

Salmon, Daniel A.; Akhtar, Aysha; Mergler, Michelle J.; Vannice, Kirsten S.; Izurieta, Hector; Ball, Robert; Lee, Grace M.; Vellozzi, Claudia; Garman, Patrick; Cunningham, Francesca; Gellin, Bruce; Koh, Howard; Lurie, Nicole

The effort to vaccinate the US population against the 2009 H1N1 influenza virus hinged, in part, on public confidence in vaccine safety. Early in the vaccine program, >20% of parents reported that they would not vaccinate their children. Concerns about the safety of the vaccines were reported by

Oral delivery of the Sj23LHD-GST antigen by Salmonella typhimurium type III secretion system protects against Schistosoma japonicum infection in mice.

Directory of Open Access Journals (Sweden)

Guo Chen

2011-09-01

Full Text Available BACKGROUND: Schistosomiasis japonica is a zoonotic parasitic disease and oral vaccine delivery system would be benefit for prevention of this disease. Although attenuated salmonella has been used as an antigen expression vector for oral vaccine development, the membrane-bound vacuoles in which bacteria reside hinders the presentation of expressed heterologous antigens to the major histocompatibility complex (MHC molecules. The present work used an attenuated Salmonella typhimurium strain VNP20009 to secretory expression of Sj23LHDGST bivalent antigen from Schistosoma japonicum and tested the protective efficacy against S. japonicum infection in orally immunized mice. METHODOLOGY/PRINCIPAL FINDINGS: Promoters (nirB or pagC were used to express the antigen (Sj23LHDGST and the Salmonella type III or α-hemolysin secretion system was employed to secrete it. The immunoblotting analysis and fluorescent microscopy revealed that the antigen was effectively expressed and delivered to the cytosol of macrophages in vitro. Among recombinant vaccine strains, an engineered VNP20009 which expressed the antigen by nirB promoter and secreted it through type III secretion system (nirB-sopE(1-104-Sj23LHD-GST efficiently protected against S. japonicum infection in a mouse model. This strain elicited a predominantly IgG(2a antibody response and a markedly increase in the production of IL-12 and IFN-γ. The flow cytometric analysis demonstrated that this strain caused T cell activation as evidenced by significantly increased expression of CD44 and CD69. CONCLUSION/SIGNIFICANCE: Oral delivery of antigen by nirB-driven Salmonella typhimurium type III secretion system is a novel, safe, inexpensive, efficient and convenient approach for schistosome vaccine development.

Randomised active programs on healthcare workers' flu vaccination in geriatric health care settings in France: the VESTA study.

Science.gov (United States)

Rothan-Tondeur, M; Filali-Zegzouti, Y; Golmard, J-L; De Wazieres, B; Piette, F; Carrat, F; Lejeune, B; Gavazzi, G

2011-02-01

Because of a lack of efficacy of influenza vaccination in elderly population, there are still numerous outbreaks in geriatric health care settings. The health care workers (HCW) flu vaccination is known to get herd immunity and decrease the impact of influenza in elderly population living in geriatric health care settings. However, the rates of vaccinated HCWs are still low in France. The French Geriatric Infection Risk Institute (ORIG) performed the VESTA study, a three-phase multicentre to identify factors limiting vaccination in HCWs, and to develop and implement active programs promoting HCWs influenza vaccination. To implement multicenter programs to enhance HCW influenza vaccination. It was a cluster randomised interventional studies. 43 geriatric health care settings (GHCSs), long term care and rehabilitation care settings in France. 1814 Health care workers from 20 GHCSs in the interventional group and 2,435 health care workers in 23 GHCSs in the control group. After the failure of a first educational program giving scientific information and. tested during the 2005-06 flu season in 43 HCSs, a second program was designed with the help of marketing experts, one year after Program 1. The objectives were to involve HCWs in the creation of "safety zones", and to give personal satisfaction. Program 2 was tested during the 2006-07 season. 20 of the 24 HCSs from the Program 1 cluster were included in the Program 2 cluster (1,814 HCWs), and 16 of the 19 HCSs from the Control 1 cluster, plus 7 new HCSs with interest in participating, were included in the Control 2 cluster (23 HCSs; 2,435 HCWs). The efficacy of each program was assessed by calculating and comparing the percentage of vaccinated HCWs, from all HCSs taken together, in the program and control clusters. Program 1 failed to increase the HCW vaccination coverage rate (VCR) (Program 1: 34%; Control 1: 32%; p > 0.05),). Program 2 increased the VCR in HCWs (Program 2: 44%; Control 2: 27%; Chi2 test, p active

Vaccination Week in the Americas, 2011: an opportunity to assess the routine vaccination program in the Bolivarian Republic of Venezuela.

Science.gov (United States)

Sánchez, Daniel; Sodha, Samir V; Kurtis, Hannah J; Ghisays, Gladys; Wannemuehler, Kathleen A; Danovaro-Holliday, M Carolina; Ropero-Álvarez, Alba María

2015-04-17

Vaccination Week in the Americas (VWA) is an annual initiative in countries and territories of the Americas every April to highlight the work of national expanded programs on immunization (EPI) and increase access to vaccination services for high-risk population groups. In 2011, as part of VWA, Venezuela targeted children aged less than 6 years in 25 priority border municipalities using social mobilization to increase institution-based vaccination. Implementation of social communication activities was decentralized to the local level. We conducted a survey in one border municipality of Venezuela to evaluate the outcome of VWA 2011 and provide a snapshot of the overall performance of the routine EPI at that level. We conducted a coverage survey, using stratified cluster sampling, in the Venezuelan municipality of Bolivar (bordering Colombia) in August 2011. We collected information for children aged 85%, with a few exceptions. Low levels of VWA awareness among caregivers probably contributed to the limited vaccination of eligible children during the VWA activities in Bolivar in 2011. However, vaccine coverage for most EPI vaccines was high. Additionally, high vaccination card availability and high participation in VWA among those caregivers aware of it in 2011 suggest public trust in the EPI program in the municipality. Health authorities have used survey findings to inform changes to the routine EPI and better VWA implementation in subsequent years.

Salmonella typhi time to change empiric treatment

DEFF Research Database (Denmark)

Gade, C.; Engberg, J.; Weis, N.

2008-01-01

In the present case series report we describe seven recent cases of typhoid fever. All the patients were travellers returning from Pakistan, where typhoid is endemic. Salmonella typhi isolated from the patients by blood culture were reported as intermediary susceptible to fluoroquinolones in six...... out of seven cases. We recommend that empiric treatment of suspected cases of typhoid fever includes a third generation cephalosporin such as ceftriaxon. Furthermore, the present report stresses the importance of typhoid vaccination of travellers to areas where typhoid is endemic Udgivelsesdato: 2008/9/29...

Effects of a nurse-managed program on hepatitis A and B vaccine completion among homeless adults.

Science.gov (United States)

Nyamathi, Adeline; Liu, Yihang; Marfisee, Mary; Shoptaw, Steven; Gregerson, Paul; Saab, Sammy; Leake, Barbara; Tyler, Darlene; Gelberg, Lillian

2009-01-01

Hepatitis B virus (HBV) infection constitutes a major health problem for homeless persons. Ability to complete an HBV vaccination series is complicated by the need to prioritize competing needs, such as addiction issues, safe places to sleep, and food, over health concerns. The objectives of this study were to evaluate the effectiveness of a nurse-case-managed intervention compared with that of two standard programs on completion of the combined hepatitis A virus (HAV) and HBV vaccine series among homeless adults and to assess sociodemographic factors and risk behaviors related to the vaccine completion. A randomized, three-group, prospective, quasi-experimental design was conducted with 865 homeless adults residing in homeless shelters, drug rehabilitation sites, and outdoor areas in the Skid Row area of Los Angeles. The programs included (a) nurse-case-managed sessions plus targeted hepatitis education, incentives, and tracking (NCMIT); (b) standard targeted hepatitis education plus incentives and tracking (SIT); and (c) standard targeted hepatitis education and incentives only (SI). Sixty-eight percent of the NCMIT participants completed the three-series vaccine at 6 months, compared with 61% of SIT participants and 54% of SI participants. NCMIT participants had almost 2 times greater odds of completing vaccination than those of participants in the SI program. Completers were more likely to be older, to be female, to report fair or poor health, and not to have participated in a self-help drug treatment program. Newly homeless White adults were significantly less likely than were African Americans to complete the vaccine series. The use of vaccination programs incorporating nurse case management and tracking is critical in supporting adherence to completion of a 6-month HAV/HBV vaccine. The finding that White homeless persons were the least likely to complete the vaccine series suggests that programs tailored to address their unique cultural issues are needed.

Uptake of a government-funded pertussis-containing booster vaccination program for parents of new babies in Victoria, Australia.

Science.gov (United States)

Rowe, Stacey L; Cunningham, Helen M; Franklin, Lucinda J; Lester, Rosemary A

2015-04-08

An epidemic of Bordetella pertussis in Victoria, Australia, led to the implementation of a Government-funded vaccination program for parents of new babies. The rationale was to protect unimmunised infants from infection by vaccinating parents with a pertussis-containing vaccine. This is known as cocooning. To estimate uptake of the vaccine among parents of new babies, two-and-a-half years after the program was implemented. A state-wide cross-sectional survey of parents was conducted to ascertain vaccine uptake, and to identify where and when the vaccination took place. Surveys were administered between 15 February and 14 March 2012, inclusive. Of 6308 surveys distributed, 2510 completed surveys were returned (response rate 40%). Ninety-five surveys completed outside the study period were excluded, leaving 2415 available for analysis. Overall, 1937 (80%) mothers and 1385 (70%) fathers were vaccinated in relation to the birth of their most recent child. A majority of mothers were vaccinated in hospital (62%). Most fathers were vaccinated by a general practitioner (72%). The most common point at which mothers were vaccinated was before their child turned two weeks of age (65%). Fathers' vaccination time-point varied more widely: during pregnancy (25%); before their child turned two weeks of age (29%); and when their child was between two and eight weeks of age (28%). Results of this survey indicated excellent uptake of the vaccine among both mothers and fathers under the Government-funded cocooning program. The findings are suggestive of an effective communications program designed to raise awareness of the risks of pertussis, and to promote availability of the funded vaccination program. The results may contribute to policy implementation of adult immunisation programs such as cocooning. Copyright © 2015 Elsevier Ltd. All rights reserved.

Activation of Salmonella Typhi-specific regulatory T cells in typhoid disease in a wild-type S. Typhi challenge model.

OpenAIRE

Monica A McArthur; Stephanie Fresnay; Laurence S Magder; Thomas C Darton; Claire Jones; Claire S Waddington; Christoph J Blohmke; Gordon Dougan; Brian Angus; Myron M Levine; Andrew J Pollard; Marcelo B Sztein

2015-01-01

Salmonella Typhi (S. Typhi), the causative agent of typhoid fever, causes significant morbidity and mortality worldwide. Currently available vaccines are moderately efficacious, and identification of immunological responses associated with protection or disease will facilitate the development of improved vaccines. We investigated S. Typhi-specific modulation of activation and homing potential of circulating regulatory T cells (Treg) by flow and mass cytometry using specimens obtained from a h...

Incidence of cervical lesions in Danish women before and after implementation of a national HPV vaccination program

DEFF Research Database (Denmark)

Baldur-Felskov, Birgitte; Dehlendorff, Christian; Junge, Jette

2014-01-01

+) and cervical intraepithelial neoplasia grade 2 or worse (CIN2+) increased in all age groups in 2000-2010. After introduction of the quadrivalent HPV vaccine into the vaccination program, the incidence of atypia+ decreased significantly in women younger than 18 years (EAPC -33.4%; 95% CI -49.6; -12.0) and in 18......PURPOSE: Approximately 7% of cervical cancers and about 50% of high-grade cervical precursor lesions are caused by human papillomavirus (HPV) types 16 and 18. Denmark introduced the quadrivalent HPV vaccine into the vaccination program for 12-year-old girls in 2009 supplemented by a first catch......-up program for 13-15-year-old girls in 2008, and a second program for women up to the age of 27 years in 2012; all with high vaccination coverage. The aim of this study was to evaluate the effectiveness of the vaccine by comparing the incidence trends of cervical lesions before and after its introduction...

aroA-Deficient Salmonella enterica Serovar Typhimurium Is More Than a Metabolically Attenuated Mutant

Science.gov (United States)

Frahm, Michael; Kocijancic, Dino; Rohde, Manfred; Eckweiler, Denitsa; Bielecka, Agata; Bueno, Emilio; Cava, Felipe; Abraham, Wolf-Rainer; Curtiss, Roy; Häussler, Susanne; Erhardt, Marc; Weiss, Siegfried

2016-01-01

ABSTRACT Recombinant attenuated Salmonella enterica serovar Typhimurium strains are believed to act as powerful live vaccine carriers that are able to elicit protection against various pathogens. Auxotrophic mutations, such as a deletion of aroA, are commonly introduced into such bacteria for attenuation without incapacitating immunostimulation. In this study, we describe the surprising finding that deletion of aroA dramatically increased the virulence of attenuated Salmonella in mouse models. Mutant bacteria lacking aroA elicited increased levels of the proinflammatory cytokine tumor necrosis factor alpha (TNF-α) after systemic application. A detailed genetic and phenotypic characterization in combination with transcriptomic and metabolic profiling demonstrated that ΔaroA mutants display pleiotropic alterations in cellular physiology and lipid and amino acid metabolism, as well as increased sensitivity to penicillin, complement, and phagocytic uptake. In concert with other immunomodulating mutations, deletion of aroA affected flagellin phase variation and gene expression of the virulence-associated genes arnT and ansB. Finally, ΔaroA strains displayed significantly improved tumor therapeutic activity. These results highlight the importance of a functional shikimate pathway to control homeostatic bacterial physiology. They further highlight the great potential of ΔaroA-attenuated Salmonella for the development of vaccines and cancer therapies with important implications for host-pathogen interactions and translational medicine. PMID:27601574

Natural and vaccine-mediated immunity to Salmonella Typhimurium is impaired by the helminth Nippostrongylus brasiliensis.

Directory of Open Access Journals (Sweden)

Saeeda Bobat

2014-12-01

Full Text Available The impact of exposure to multiple pathogens concurrently or consecutively on immune function is unclear. Here, immune responses induced by combinations of the bacterium Salmonella Typhimurium (STm and the helminth Nippostrongylus brasiliensis (Nb, which causes a murine hookworm infection and an experimental porin protein vaccine against STm, were examined.Mice infected with both STm and Nb induced similar numbers of Th1 and Th2 lymphocytes compared with singly infected mice, as determined by flow cytometry, although lower levels of secreted Th2, but not Th1 cytokines were detected by ELISA after re-stimulation of splenocytes. Furthermore, the density of FoxP3+ T cells in the T zone of co-infected mice was lower compared to mice that only received Nb, but was greater than those that received STm. This reflected the intermediate levels of IL-10 detected from splenocytes. Co-infection compromised clearance of both pathogens, with worms still detectable in mice weeks after they were cleared in the control group. Despite altered control of bacterial and helminth colonization in co-infected mice, robust extrafollicular Th1 and Th2-reflecting immunoglobulin-switching profiles were detected, with IgG2a, IgG1 and IgE plasma cells all detected in parallel. Whilst extrafollicular antibody responses were maintained in the first weeks after co-infection, the GC response was less than that in mice infected with Nb only. Nb infection resulted in some abrogation of the longer-term development of anti-STm IgG responses. This suggested that prior Nb infection may modulate the induction of protective antibody responses to vaccination. To assess this we immunized mice with porins, which confer protection in an antibody-dependent manner, before challenging with STm. Mice that had resolved a Nb infection prior to immunization induced less anti-porin IgG and had compromised protection against infection.These findings demonstrate that co-infection can radically alter

Surveillance of adverse effects following vaccination and safety of immunization programs.

Science.gov (United States)

Waldman, Eliseu Alves; Luhm, Karin Regina; Monteiro, Sandra Aparecida Moreira Gomes; Freitas, Fabiana Ramos Martin de

2011-02-01

The aim of the review was to analyze conceptual and operational aspects of systems for surveillance of adverse events following immunization. Articles available in electronic format were included, published between 1985 and 2009, selected from the PubMed/Medline databases using the key words "adverse events following vaccine surveillance", "post-marketing surveillance", "safety vaccine" and "Phase IV clinical trials". Articles focusing on specific adverse events were excluded. The major aspects underlying the Public Health importance of adverse events following vaccination, the instruments aimed at ensuring vaccine safety, and the purpose, attributes, types, data interpretation issues, limitations, and further challenges in adverse events following immunization were describe, as well as strategies to improve sensitivity. The review was concluded by discussing the challenges to be faced in coming years with respect to ensuring the safety and reliability of vaccination programs.

Effects of gamma radiation and heat on immunogenicity and morphology of Salmonella typhimurium

International Nuclear Information System (INIS)

Santos Araujo, E. dos; Silva, D.M.

1979-01-01

Results are presented about immunogenicity of vaccines prepared from Salmonella typhimurium suspensions submitted to 0,55 MR and 1,10 MR of gamma radiation and heating at 60 0 C, (60 min) and at 100 0 C, (3 min) correlated with the cell morphology alterations observed at electron microscopy. The results of mouse-protection tests showed that prepared vaccines with 0,55 MR and with heating at 60 0 C, 60 min were identical and more efficient than the two other treatments. The electronmicrografies also showed one positive correlation between morphological alterations caused by the treatments and the immunogenicities. (Author) [pt

Comparative genome analysis of the high pathogenicity Salmonella Typhimurium strain UK-1.

Directory of Open Access Journals (Sweden)

Yingqin Luo

Full Text Available Salmonella enterica serovar Typhimurium, a gram-negative facultative rod-shaped bacterium causing salmonellosis and foodborne disease, is one of the most common isolated Salmonella serovars in both developed and developing nations. Several S. Typhimurium genomes have been completed and many more genome-sequencing projects are underway. Comparative genome analysis of the multiple strains leads to a better understanding of the evolution of S. Typhimurium and its pathogenesis. S. Typhimurium strain UK-1 (belongs to phage type 1 is highly virulent when orally administered to mice and chickens and efficiently colonizes lymphoid tissues of these species. These characteristics make this strain a good choice for use in vaccine development. In fact, UK-1 has been used as the parent strain for a number of nonrecombinant and recombinant vaccine strains, including several commercial vaccines for poultry. In this study, we conducted a thorough comparative genome analysis of the UK-1 strain with other S. Typhimurium strains and examined the phenotypic impact of several genomic differences. Whole genomic comparison highlights an extremely close relationship between the UK-1 strain and other S. Typhimurium strains; however, many interesting genetic and genomic variations specific to UK-1 were explored. In particular, the deletion of a UK-1-specific gene that is highly similar to the gene encoding the T3SS effector protein NleC exhibited a significant decrease in oral virulence in BALB/c mice. The complete genetic complements in UK-1, especially those elements that contribute to virulence or aid in determining the diversity within bacterial species, provide key information in evaluating the functional characterization of important genetic determinants and for development of vaccines.

Salmonella osteomyelitis

OpenAIRE

Somsri Wiwanitkit; Viroj Wiwanitkit

2016-01-01

Salmonella infection can cause four predominant clinical syndromes: enteric fever, acute gastroenteritis, bacteraemia with or without metastatic infection, and the asymptomatic carrier state. Salmonella as an aetiological agent in osteomyelitis is essentially rare and salmonella osteomyelitis in itself is predominantly seen in patients with haemoglobinopathies such as sickle cell disease or thalassemia. There are very few cases reported in the literature in which salmonella osteomyelitis is s...

Oral Challenge with Wild-Type Salmonella Typhi Induces Distinct Changes in B Cell Subsets in Individuals Who Develop Typhoid Disease.

OpenAIRE

Franklin R Toapanta; Paula J Bernal; Stephanie Fresnay; Laurence S Magder; Thomas C Darton; Claire Jones; Claire S Waddington; Christoph J Blohmke; Brian Angus; Myron M Levine; Andrew J Pollard; Marcelo B Sztein

2016-01-01

A novel human oral challenge model with wild-type Salmonella Typhi (S. Typhi) was recently established by the Oxford Vaccine Group. In this model, 104 CFU of Salmonella resulted in 65% of participants developing typhoid fever (referred here as typhoid diagnosis -TD-) 6?9 days post-challenge. TD was diagnosed in participants meeting clinical (oral temperature ?38?C for ?12h) and/or microbiological (S. Typhi bacteremia) endpoints. Changes in B cell subpopulations following S. Typhi challenge re...

Human Papillomavirus Prevalence and Herd Immunity after Introduction of Vaccination Program, Scotland, 2009-2013.

Science.gov (United States)

Cameron, Ross L; Kavanagh, Kimberley; Pan, Jiafeng; Love, John; Cuschieri, Kate; Robertson, Chris; Ahmed, Syed; Palmer, Timothy; Pollock, Kevin G J

2016-01-01

In 2008, a national human papillomavirus (HPV) immunization program using a bivalent vaccine against HPV types 16 and 18 was implemented in Scotland along with a national surveillance program designed to determine the longitudinal effects of vaccination on HPV infection at the population level. Each year during 2009-2013, the surveillance program conducted HPV testing on a proportion of liquid-based cytology samples from women undergoing their first cervical screening test for precancerous cervical disease. By linking vaccination, cervical screening, and HPV testing data, over the study period we found a decline in HPV types 16 and 18, significant decreases in HPV types 31, 33, and 45 (suggesting cross-protection), and a nonsignificant increase in HPV 51. In addition, among nonvaccinated women, HPV types 16 and 18 infections were significantly lower in 2013 than in 2009. Our results preliminarily indicate herd immunity and sustained effectiveness of the bivalent vaccine on virologic outcomes at the population level.

Successful introduction of an underutilized elderly pneumococcal vaccine in a national immunization program by integrating the pre-existing public health infrastructure.

Science.gov (United States)

Yang, Tae Un; Kim, Eunsung; Park, Young-Joon; Kim, Dongwook; Kwon, Yoon Hyung; Shin, Jae Kyong; Park, Ok

2016-03-18

Although pneumococcal vaccines had been recommended for the elderly population in South Korea for a considerable period of time, the coverage has been well below the optimal level. To increase the vaccination rate with integrating the pre-existing public health infrastructure and governmental funding, the Korean government introduced an elderly pneumococcal vaccination into the national immunization program with a 23-valent pneumococcal polysaccharide vaccine in May 2013. The aim of this study was to assess the performance of the program in increasing the vaccine coverage rate and maintaining stable vaccine supply and safe vaccination during the 20 months of the program. We qualitatively and quantitatively analyzed the process of introducing and the outcomes of the program in terms of the systematic organization, efficiency, and stability at the national level. A staggered introduction during the first year utilizing the public sector, with a target coverage of 60%, was implemented based on the public demand for an elderly pneumococcal vaccination, vaccine supply capacity, vaccine delivery capacity, safety, and sustainability. During the 20-month program period, the pneumococcal vaccine coverage rate among the population aged ≥65 years increased from 5.0% to 57.3% without a noticeable vaccine shortage or safety issues. A web-based integrated immunization information system, which includes the immunization registry, vaccine supply chain management, and surveillance of adverse events following immunization, reduced programmatic errors and harmonized the overall performance of the program. Introduction of an elderly pneumococcal vaccination in the national immunization program based on strong government commitment, meticulous preparation, financial support, and the pre-existing public health infrastructure resulted in an efficient, stable, and sustainable increase in vaccination coverage. Copyright © 2016. Published by Elsevier Ltd.

Determination method of inactivating minimal dose of gama radiation for Salmonella typhimurium

International Nuclear Information System (INIS)

Araujo, E.S.; Campos, H. de; Silva, D.M.

1979-01-01

A method for determination of minimal inactivating dose (MID) with Salmonella typhimurium is presented. This is a more efficient way to improve the irradiated vaccines. The MID found for S. thyphimurium 6.616 by binomial test was 0.55 MR. The method used allows to get a definite value for MID and requires less consumption of material, work and time in comparison with the usual procedure [pt

Investigation of the response to the enterobacterial common antigen after typhoid vaccination

Directory of Open Access Journals (Sweden)

Arlete M. Milhomem

1987-03-01

Full Text Available Antibodies against the Salmonella typhi enterobacterial common antigen (ECA and the O and H antigens were investigated in sera from healthy male subjects who had been previously vaccinated with the typhoid vaccine. No serological response to ECA was observed. Sera from subjects not previously vaccinated presented titers of ECA hemagglutinins which quantitatively were related to the presence ofH titers, but not to O agglutinins but with no statistical significance. The results are discussed in relation to the possible protective immunological mechanisms in typhoid fever.

Spatial surveillance during control of infectious diseases – Salmonella Dublin in Denmark 2002-2009

DEFF Research Database (Denmark)

Ersbøll, Annette Kjær; Nielsen, Liza Rosenbaum

2010-01-01

Salmonella Dublin is the most commonly isolated Salmonella serotype in Danish cattle and leads to economic and welfare losses in infected herds. Furthermore, it leads to high mortality in human cases. A national surveillance program for Salmonella Dublin was initiated in Denmark in October 2002. ...

Reduced salmonella fecal shedding in swine administered porcine granulocyte-colony stimulating factor (G-CSF)

Science.gov (United States)

Salmonella colonization of food animals is a concern for animal health, food safety and public health. Key objectives of pre-harvest food safety programs are to detect asymptomatic Salmonella carriage in food animals, reduce colonization, and prevent transmission of Salmonella to other animals and ...

Salmonella enterica Induces And Subverts The Plant Immune System

Directory of Open Access Journals (Sweden)

Ana Victoria Garcia

2014-04-01

Full Text Available Infections with Salmonella enterica belong to the most prominent causes of food poisoning and infected fruits and vegetables represent important vectors for salmonellosis. Whereas it was shown that plants raise defense responses against Salmonella, these bacteria persist and proliferate in various plant tissues. Recent reports shed light into the molecular interaction between plants and Salmonella, highlighting the defense pathways induced and the means used by the bacteria to escape the plant immune system and accomplish colonization. It was recently shown that plants detect Salmonella pathogen-associated molecular patterns (PAMPs, such as the flagellin peptide flg22, and activate hallmarks of the defense program known as PAMP-triggered immunity (PTI. Interestingly, certain Salmonella strains carry mutations in the flg22 domain triggering PTI, suggesting that a strategy of Salmonella is to escape plant detection by mutating PAMP motifs. Another strategy may rely on the type III secretion system (T3SS as T3SS mutants were found to induce stronger plant defense responses than wild type bacteria. Although Salmonella effector delivery into plant cells has not been shown, expression of Salmonella effectors in plant tissues shows that these bacteria also possess powerful means to manipulate the plant immune system. Altogether, the data gathered suggest that Salmonella triggers PTI in plants and evolved strategies to avoid or subvert plant immunity.

Salmonella enterica induces and subverts the plant immune system

KAUST Repository

García, Ana V.

2014-04-04

Infections with Salmonella enterica belong to the most prominent causes of food poisoning and infected fruits and vegetables represent important vectors for salmonellosis. Although it was shown that plants raise defense responses against Salmonella, these bacteria persist and proliferate in various plant tissues. Recent reports shed light into the molecular interaction between plants and Salmonella, highlighting the defense pathways induced and the means used by the bacteria to escape the plant immune system and accomplish colonization. It was recently shown that plants detect Salmonella pathogen-associated molecular patterns (PAMPs), such as the flagellin peptide flg22, and activate hallmarks of the defense program known as PAMP-triggered immunity (PTI). Interestingly, certain Salmonella strains carry mutations in the flg22 domain triggering PTI, suggesting that a strategy of Salmonella is to escape plant detection by mutating PAMP motifs. Another strategy may rely on the type III secretion system (T3SS) as T3SS mutants were found to induce stronger plant defense responses than wild type bacteria. Although Salmonella effector delivery into plant cells has not been shown, expression of Salmonella effectors in plant tissues shows that these bacteria also possess powerful means to manipulate the plant immune system. Altogether, these data suggest that Salmonella triggers PTI in plants and evolved strategies to avoid or subvert plant immunity. 2014 Garca and Hirt.

Salmonella: Salmonellosis

DEFF Research Database (Denmark)

Löfström, Charlotta; Hansen, Trine; Maurischat, Sven

2015-01-01

Salmonella remains one of the most important zoonotic pathogenic bacteria and is the causative agents of salmonellosis. The aim of this article is to give an overview of Salmonella and salmonellosis, starting by describing the characteristics of the microorganism Salmonella, including biochemical...

Measles, immune suppression and vaccination: direct and indirect nonspecific vaccine benefits.

Science.gov (United States)

Mina, Michael J

2017-06-01

The measles virus is among the most transmissible viruses known to infect humans. Prior to measles vaccination programs, measles infected over 95% of all children and was responsible for over 4 million deaths each year. Measles vaccination programs have been among the greatest public health achievements reducing, eliminating endemic measles in the whole of the Americas and across much of the globe. Where measles vaccines are introduced, unexpectedly large reductions in all-cause childhood mortality have been observed. These gains appear to derive in part from direct heterologous benefits of measles vaccines that enhance innate and adaptive immune responses. Additionally, by preventing measles infections, vaccination prevents measles-associated short- and long-term immunomodulating effects. Before vaccination, these invisible hallmarks of measles infections increased vulnerability to non-measles infections in nearly all children for weeks, months, or years following acute infections. By depleting measles incidence, vaccination has had important indirect benefits to reduce non-measles mortality. Delineating the relative importance of these two modes of survival benefits following measles vaccine introduction is of critical public health importance. While both support continued unwavering global commitments to measles vaccination programs until measles eradication is complete, direct heterologous benefits of measles vaccination further support continued commitment to measles vaccination programs indefinitely. We discuss what is known about direct and indirect nonspecific measles vaccine benefits, and their implications for continued measles vaccination programs. © 2017 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Salmonella typhi--tid til aendring af den empiriske behandling

DEFF Research Database (Denmark)

Gade, Christina; Engberg, Jørgen; Weis, Nina

2008-01-01

In the present case series report we describe seven recent cases of typhoid fever. All the patients were travellers returning from Pakistan, where typhoid is endemic. Salmonella typhi isolated from the patients by blood culture were reported as intermediary susceptible to fluoroquinolones in six...... out of seven cases. We recommend that empiric treatment of suspected cases of typhoid fever includes a third generation cephalosporin such as ceftriaxon. Furthermore, the present report stresses the importance of typhoid vaccination of travellers to areas where typhoid is endemic. Udgivelsesdato: 2008...

Demand for pneumococcal vaccination under subsidy program for the elderly in Japan.

Science.gov (United States)

Kondo, Masahide; Yamamura, Mariko; Hoshi, Shu-Ling; Okubo, Ichiro

2012-09-12

Vaccination programs often organize subsidies and public relations in order to obtain high uptake rates and coverage. However, effects of subsidies and public relations have not been studied well in the literature. In this study, the demand function of pneumococcal vaccination among the elderly in Japan is estimated, incorporating effects of public relations and subsidy. Using a data from a questionnaire survey sent to municipalities, the varying and constant elasticity models were applied to estimate the demand function. The response variable is the uptake rate. Explanatory variables are: subsidy supported shot price, operating years of the program, target population size for vaccination, shot location intensity, income and various public relations tools. The best model is selected by c-AIC, and varying and constant price elasticities are calculated from estimation results. The vaccine uptake rate and the shot price have a negative relation. From the results of varying price elasticity, the demand for vaccination is elastic at municipalities with a shot price higher than 3,708 JPY (35.7 USD). Effects of public relations on the uptake rate are not found. It can be suggested that municipalities with a shot price higher than 3,708 JPY (35.7 USD) could subsidize more and reduce price to increase the demand for vaccination. Effects of public relations are not confirmed in this study, probably due to measurement errors of variables used for public relations, and studies at micro level exploring individual's response to public relations would be required.

Assessing genital human papillomavirus genoprevalence in young Australian women following the introduction of a national vaccination program.

Science.gov (United States)

Osborne, Sarah L; Tabrizi, Sepehr N; Brotherton, Julia M L; Cornall, Alyssa M; Wark, John D; Wrede, C David; Jayasinghe, Yasmin; Gertig, Dorota M; Pitts, Marian K; Garland, Suzanne M

2015-01-01

Following the implementation of Australia's National HPV Vaccination Program in April 2007, this study evaluated the prevalence of vaccine-targeted human papillomavirus (HPV) genotypes (HPV 6, 11, 16, 18) amongst vaccine-eligible young women. Between September 2011 and August 2013, women from Victoria, Australia aged 18-25 were recruited through targeted advertising on the social networking website Facebook. Participants completed an online questionnaire, and sexually active women were asked to provide a self-collected vaginal swab for HPV deoxyribonucleic acid (DNA) detection and genotyping. Samples positive for HPV were genotyped using the Linear Array HPV genotyping test (Roche Diagnostics). Self-reported HPV vaccination details were verified with the National HPV Vaccination Program Register (NHVPR). Of 431 vaginal swabs, 24.8% were positive for HPV DNA. Vaccine-targeted HPV genotypes were detected in only seven (1.6%) samples; all HPV 16 (of the six HPV 16 positive vaccinated women, all had received the vaccine after sexual debut). There were no cases of HPV 6, 11 or 18 identified. HPV types 51, 59, 73, 84, and 89 were the most prevalent genotypes. Vaccination rates were high, with 77.3% of participants having received all three doses of the vaccine, and there was an 89.8% concordance between self-reported and registry-reported HPV vaccination status. Strong associations were observed between vaccination status, age, language spoken at home and country of birth, as well as between HPV detection and the number of male sexual partners. Preliminary data from this study demonstrate a very low prevalence of vaccine-related HPV genotypes amongst vaccine-eligible women from Victoria, Australia. We were able to use Facebook to effectively reach and recruit young women to participate in the assessment of the impact of Australia's HPV vaccination program. Copyright © 2014 Elsevier Ltd. All rights reserved.

O:2-CRM(197) conjugates against Salmonella Paratyphi A.

Science.gov (United States)

Micoli, Francesca; Rondini, Simona; Gavini, Massimiliano; Lanzilao, Luisa; Medaglini, Donata; Saul, Allan; Martin, Laura B

2012-01-01

Enteric fevers remain a common and serious disease, affecting mainly children and adolescents in developing countries. Salmonella enterica serovar Typhi was believed to cause most enteric fever episodes, but several recent reports have shown an increasing incidence of S. Paratyphi A, encouraging the development of a bivalent vaccine to protect against both serovars, especially considering that at present there is no vaccine against S. Paratyphi A. The O-specific polysaccharide (O:2) of S. Paratyphi A is a protective antigen and clinical data have previously demonstrated the potential of using O:2 conjugate vaccines. Here we describe a new conjugation chemistry to link O:2 and the carrier protein CRM(197), using the terminus 3-deoxy-D-manno-octulosonic acid (KDO), thus leaving the O:2 chain unmodified. The new conjugates were tested in mice and compared with other O:2-antigen conjugates, synthesized adopting previously described methods that use CRM(197) as carrier protein. The newly developed conjugation chemistry yielded immunogenic conjugates with strong serum bactericidal activity against S. Paratyphi A.

O:2-CRM(197 conjugates against Salmonella Paratyphi A.

Directory of Open Access Journals (Sweden)

Francesca Micoli

Full Text Available Enteric fevers remain a common and serious disease, affecting mainly children and adolescents in developing countries. Salmonella enterica serovar Typhi was believed to cause most enteric fever episodes, but several recent reports have shown an increasing incidence of S. Paratyphi A, encouraging the development of a bivalent vaccine to protect against both serovars, especially considering that at present there is no vaccine against S. Paratyphi A. The O-specific polysaccharide (O:2 of S. Paratyphi A is a protective antigen and clinical data have previously demonstrated the potential of using O:2 conjugate vaccines. Here we describe a new conjugation chemistry to link O:2 and the carrier protein CRM(197, using the terminus 3-deoxy-D-manno-octulosonic acid (KDO, thus leaving the O:2 chain unmodified. The new conjugates were tested in mice and compared with other O:2-antigen conjugates, synthesized adopting previously described methods that use CRM(197 as carrier protein. The newly developed conjugation chemistry yielded immunogenic conjugates with strong serum bactericidal activity against S. Paratyphi A.

Coadministration of cruzipain and GM-CSF DNAs, a new immunotherapeutic vaccine against Trypanosoma cruzi infection.

Science.gov (United States)

Cerny, Natacha; Sánchez Alberti, Andrés; Bivona, Augusto E; De Marzi, Mauricio C; Frank, Fernanda M; Cazorla, Silvia I; Malchiodi, Emilio L

2016-01-01

Therapeutic vaccine research and development are especially important in Chagas disease considering the characteristics of the chronic infection and the number of people in the Americas living with a parasite infection for decades. We have previously reported the efficacy of attenuated Salmonella enterica (S) carrying plasmid encoding cruzipain (SCz) to protect against Trypanosoma cruzi infection. In the present work we investigated whether Cz DNA vaccine immunotherapy could be effective in controlling an ongoing T. cruzi infection in mice. We here report the intramuscular administration of naked Cz DNA or the oral administration of Salmonella as Cz DNA delivery system as therapeutic vaccines in mice during acute or chronic infection. The coadministration of a plasmid encoding GM-CSF improved vaccine performance, indicating that the stimulation of innate immune cells is needed in the event of an ongoing infection. These therapeutic vaccines were able to address the response to a protective and sustained Th1 biased profile not only against Cz but also against a variety of parasite antigens. The combined therapeutic vaccine during the chronic phase of infection prevents tissue pathology as shown by a reduced level of enzyme activity characteristic of tissue damage and a tissue status compatible with normal tissue. The obtained results suggest that immunotherapy with Cz and GM-CSF DNAs, either alone or in combination with other drug treatments, may represent a promising alternative for Chagas disease therapy.

Impact of School Flu Vaccine Program on Student Absences

Science.gov (United States)

Plaspohl, Sara S.; Dixon, Betty T.; Streater, James A.; Hausauer, Elizabeth T.; Newman, Christopher P.; Vogel, Robert L.

2014-01-01

Literature provides evidence that school attendance correlates with academic performance and student success. Influenza is a contributing factor to school absences. Primary prevention for influenza includes immunization. School-located influenza vaccine (SLIV) programs provide greater access for students to be immunized. A retrospective review of…

Is a HIV vaccine a viable option and at what price? An economic evaluation of adding HIV vaccination into existing prevention programs in Thailand

OpenAIRE

Leelahavarong, Pattara; Teerawattananon, Yot; Werayingyong, Pitsaphun; Akaleephan, Chutima; Premsri, Nakorn; Namwat, Chawetsan; Peerapatanapokin, Wiwat; Tangcharoensathien, Viroj

2011-01-01

Abstract Background This study aims to determine the maximum price at which HIV vaccination is cost-effective in the Thai healthcare setting. It also aims to identify the relative importance of vaccine characteristics and risk behavior changes among vaccine recipients to determine how they affect this cost-effectiveness. Methods A semi-Markov model was developed to estimate the costs and health outcomes of HIV prevention programs combined with HIV vaccination in comparison to the existing HIV...

Relationship among fecal coliforms, Escherichia coli, and Salmonella spp. in shellfish.

OpenAIRE

Hood, M A; Ness, G E; Blake, N J

1983-01-01

The relationship of fecal coliforms, Escherichia coli, and Salmonella spp. was examined in freshly harvested and stored shellfish. In 16 of 40 freshly collected oyster samples, fecal coliform levels were above the recommended wholesale level suggested by the National Shellfish Sanitation Program (less than or equal to 230/100 g), and Salmonella spp. were present in three of these samples. Salmonella spp. were not, however, present in any sample containing less than 230 fecal coliforms per 100...

Human Papillomavirus Prevalence and Herd Immunity after Introduction of Vaccination Program, Scotland, 2009–2013

Science.gov (United States)

Kavanagh, Kimberley; Pan, Jiafeng; Love, John; Cuschieri, Kate; Robertson, Chris; Ahmed, Syed; Palmer, Timothy; Pollock, Kevin G.J.

2016-01-01

In 2008, a national human papillomavirus (HPV) immunization program using a bivalent vaccine against HPV types 16 and 18 was implemented in Scotland along with a national surveillance program designed to determine the longitudinal effects of vaccination on HPV infection at the population level. Each year during 2009–2013, the surveillance program conducted HPV testing on a proportion of liquid-based cytology samples from women undergoing their first cervical screening test for precancerous cervical disease. By linking vaccination, cervical screening, and HPV testing data, over the study period we found a decline in HPV types 16 and 18, significant decreases in HPV types 31, 33, and 45 (suggesting cross-protection), and a nonsignificant increase in HPV 51. In addition, among nonvaccinated women, HPV types 16 and 18 infections were significantly lower in 2013 than in 2009. Our results preliminarily indicate herd immunity and sustained effectiveness of the bivalent vaccine on virologic outcomes at the population level. PMID:26692336

Human rotavirus vaccine is highly efficacious when coadministered with routine expanded program of immunization vaccines including oral poliovirus vaccine in Latin America.

Science.gov (United States)

Tregnaghi, Miguel W; Abate, Héctor J; Valencia, Alejandra; Lopez, Pio; Da Silveira, Themis Reverbel; Rivera, Luis; Rivera Medina, Doris Maribel; Saez-Llorens, Xavier; Gonzalez Ayala, Silvia Elena; De León, Tirza; Van Doorn, Leen-Jan; Pilar Rubio, Maria Del; Suryakiran, Pemmaraju Venkata; Casellas, Javier M; Ortega-Barria, Eduardo; Smolenov, Igor V; Han, Htay-Htay

2011-06-01

The efficacy of a rotavirus vaccine against severe rotavirus gastroenteritis when coadministered with routine Expanded Program on Immunization (EPI) vaccines including oral polio vaccine (OPV) was evaluated in this study. Double-blind, randomized (2:1), placebo-controlled study conducted across 6 Latin American countries. Healthy infants (N = 6568) 6 to 12 weeks of age received 2 doses of RIX4414 vaccine or placebo following a 0, 1- to 2-month schedule. Routine vaccines including OPV were coadministered according to local EPI schedule. Vaccine efficacy (VE) against severe rotavirus gastroenteritis caused by circulating wild-type rotavirus from 2 weeks post-Dose 2 until 1 year of age was calculated with 95% confidence interval [CI]. Safety was assessed during the entire study period. Immunogenicity of RIX4414 and OPV was also assessed. During the efficacy follow-up period (mean duration = 7.4 months), 7 and 19 cases of severe rotavirus gastroenteritis were reported in the vaccine and placebo groups, respectively, with a VE of 81.6% (95% CI: 54.4-93.5). VE against severe rotavirus gastroenteritis caused by G1 type was 100% (95% CI: rotavirus types, respectively. There was no difference (P = 0.514) in the incidence of serious adverse events reported in the 2 groups. Antirotavirus IgA seropositivity rate at 1 to 2 months post-Dose 2 was 61.4% (95% CI: 53.7-68.6) in the RIX4414 group; similar seroprotection rates (≥96.0%) against the 3 antipoliovirus types was observed 1 month post-Dose 3 of OPV in both groups. RIX4414 was highly efficacious against severe rotavirus gastroenteritis caused by the circulating wild-type rotavirus (G1 and non-G1) when coadministered with routine EPI vaccines including OPV.

Vaccine Rejecting Parents' Engagement With Expert Systems That Inform Vaccination Programs.

Science.gov (United States)

Attwell, Katie; Leask, Julie; Meyer, Samantha B; Rokkas, Philippa; Ward, Paul

2017-03-01

In attempting to provide protection to individuals and communities, childhood immunization has benefits that far outweigh disease risks. However, some parents decide not to immunize their children with some or all vaccines for reasons including lack of trust in governments, health professionals, and vaccine manufacturers. This article employs a theoretical analysis of trust and distrust to explore how twenty-seven parents with a history of vaccine rejection in two Australian cities view the expert systems central to vaccination policy and practice. Our data show how perceptions of the profit motive generate distrust in the expert systems pertaining to vaccination. Our participants perceived that pharmaceutical companies had a pernicious influence over the systems driving vaccination: research, health professionals, and government. Accordingly, they saw vaccine recommendations in conflict with the interests of their child and "the system" underscored by malign intent, even if individual representatives of this system were not equally tainted. This perspective was common to parents who declined all vaccines and those who accepted some. We regard the differences between these parents-and indeed the differences between vaccine decliners and those whose Western medical epistemology informs reflexive trust-as arising from the internalization of countering views, which facilitates nuance.

Role of word-of-mouth for programs of voluntary vaccination: A game-theoretic approach.

Science.gov (United States)

Bhattacharyya, Samit; Bauch, Chris T; Breban, Romulus

2015-11-01

We propose a model describing the synergetic feedback between word-of-mouth (WoM) and epidemic dynamics controlled by voluntary vaccination. The key feature consists in combining a game-theoretic model for the spread of WoM and a compartmental model describing VSIR disease dynamics in the presence of a program of voluntary vaccination. We evaluate and compare two scenarios for determinants of behavior, depending on what WoM disseminates: (1) vaccine advertising, which may occur whether or not an epidemic is ongoing and (2) epidemic status, notably disease prevalence. Understanding the synergy between the two strategies could be particularly important for designing voluntary vaccination campaigns. We find that, in the initial phase of an epidemic, vaccination uptake is determined more by vaccine advertising than the epidemic status. As the epidemic progresses, epidemic status becomes increasingly important for vaccination uptake, considerably accelerating vaccination uptake toward a stable vaccination coverage. Copyright © 2015 Elsevier Inc. All rights reserved.

Understanding motivators and barriers of hospital-based obstetric and pediatric health care worker influenza vaccination programs in Australia.

Science.gov (United States)

Tuckerman, Jane L; Shrestha, Lexa; Collins, Joanne E; Marshall, Helen S

2016-07-02

Understanding motivators and barriers of health care worker (HCW) vaccination programs is important for determining strategies to improve uptake. The aim of this study was to explore key drivers and HCW decision making related to recommended vaccines and seasonal influenza vaccination programs. We used a qualitative approach with semi-structured one-to-one interviews with 22 HCWs working at a tertiary pediatric and obstetric hospital in South Australia. A thematic analysis and coding were used to examine data. Key motivators that emerged included: sense of responsibility, convenience and ease of access, rotating trolleys, the influenza vaccine being free, basic knowledge about influenza and influenza vaccination, peer pressure, personal values and family culture, as well as the culture of support for the program. Personal decisions were the major barrier to HCWs receiving the influenza vaccine which were predominantly self-protection related or due to previous experience or fear of adverse reactions. Other barriers that emerged were misconceptions about the influenza vaccine, needle phobia and privacy concerns. This study identified both attitudinal and structural barriers that could be addressed to improve uptake of the seasonal influenza vaccine.

Using the 4 Pillars™ Practice Transformation Program to increase adolescent human papillomavirus, meningococcal, tetanus-diphtheria-pertussis and influenza vaccination.

Science.gov (United States)

Zimmerman, Richard K; Raviotta, Jonathan M; Nowalk, Mary Patricia; Moehling, Krissy K; Reis, Evelyn Cohen; Humiston, Sharon G; Lin, Chyongchiou Jeng

2017-10-27

To report the results of an intervention using the 4 Pillars™ Practice Transformation Program (4 Pillars™ Program) to increase adolescent vaccinations including human papillomavirus vaccine (HPV) and influenza vaccines, which remain underutilized in this population. Eleven pediatric and family medicine practices, previously control sites from a randomized controlled cluster trial, with ≥50 adolescent patients participated. The 4 Pillars™ Program was the foundation of the intervention. De-identified demographic, office visit and vaccination data were derived from electronic medical record extractions for patients whose date of birth was 4/1/1997 to 4/1/2004 (ages 11-17years at baseline). Vaccination rates for HPV, influenza, tetanus-pertussis-diphtheria (Tdap) and meningococcal (MenACWY) vaccines were determined for all eligible patients pre- and post intervention (i.e., vaccination rates on 4/1/2015 and 4/30/2016). Among 9473 patients ages 11-17years at baseline (4/1/2015), mean pre-intervention vaccination rates for HPV initiation and completion, meningococcal, Tdap and influenza vaccines were below national levels. Rates increased significantly post intervention (P<0.001) for HPV initiation which increased 17.1 percentage points (PP) from 51.4%; HPV completion increased 14.8PP from 30.7%, meningococcal vaccine uptake increased 16.6PP from 79.1%, Tdap vaccine uptake increased 14.6PP from 76.9%. Influenza vaccine uptake did not increase significantly (2.3PP from 40.1%). In the regression using generalized estimating equations, odds of vaccination were higher for younger, non-white adolescents for all vaccines; being in a smaller practice decreased the odds of Tdap vaccination but increased the odds of influenza vaccination. Clinically and statistically significant improvements in HPV series initiation and completion, and meningococcal and Tdap vaccinations were observed in primary care practices implementing the 4 Pillars™ Practice Transformation Program

Rotavirus vaccines

Science.gov (United States)

Yen, Catherine; Tate, Jacqueline E; Hyde, Terri B; Cortese, Margaret M; Lopman, Benjamin A; Jiang, Baoming; Glass, Roger I; Parashar, Umesh D

2014-01-01

Rotavirus is the leading cause of severe diarrhea among children rotavirus vaccines have been efficacious and effective, with many countries reporting substantial declines in diarrheal and rotavirus-specific morbidity and mortality. However, the full public health impact of these vaccines has not been realized. Most countries, including those with the highest disease burden, have not yet introduced rotavirus vaccines into their national immunization programs. Research activities that may help inform vaccine introduction decisions include (1) establishing effectiveness, impact, and safety for rotavirus vaccines in low-income settings; (2) identifying potential strategies to improve performance of oral rotavirus vaccines in developing countries, such as zinc supplementation; and (3) pursuing alternate approaches to oral vaccines, such as parenteral immunization. Policy- and program-level barriers, such as financial implications of new vaccine introductions, should be addressed to ensure that countries are able to make informed decisions regarding rotavirus vaccine introduction. PMID:24755452

Inhibitory Effects of Several Essential Oils towards Salmonella typhimurium, Salmonella paratyphi A and Salmonella paratyphi B

Directory of Open Access Journals (Sweden)

S.F. Mazhar

2014-09-01

Full Text Available Plant essential oils are natural products extracted from plants and because of their antimicrobial properties can be used as natural additives in foods. They are also useful for decontamination of food-borne pathogens and can be a safe additive in foods. The antimicrobial activities of essential oils belonging to Saturiea hortensis, Thymus vulgaris, Mentha polegium, Cuminum cyminum, Lavandula officinalis and Mentha viridis L. (spearmint were investigated at different concentrations (0.1, 0.3, 0.5, 1, 2, 5 and 10%v/v against Salmonella typhimurium, Salmonella paratyphi A and Salmonella paratyphi B by using the agar well diffusion method. Essential oils showed inhibitory effect on Salmonella spp. in the agar well diffusion assay. In addition, the capability of essential oils for decontamination of minced row beef, ground beef, minced raw chicken and minced raw fish inoculated with Salmonella spp. at 0.1 and 0.5%v/v were assessed. Reduction of the Salmonella spp. population was observed following the inoculation of the cultures with 0.1 and 0.5%v/v essential oils.

STUDY ON FEASIBILITY AND LOGISTICS OF VACCINATION WITH TYPHOID VI-VACCINE ON SCHOOL CHILDREN IN NORTH JAKARTA INDONESIA: ANALYSIS OF THE VACCINATION COST

Directory of Open Access Journals (Sweden)

Roy G.A. Massie

2012-11-01

Full Text Available Background: In recent years, Indonesia government has become increasingly concerned with the issues of financing childhood vaccines and immunization programs including vaccine for typhoid  fever. The objective of the analysis is to provide alternative resources and to provide understandable data generated from the Study on Feasibility and Logistics of Vaccination School Age Children With Typhoid Vi-Vaccine in North Jakarta Indonesia. Methods: The analysis was focus on measurement of the cost for vaccinating school children with Typhoid Vi-vaccine from 18 selected primary schools in North Jakarta. The primary source of data was generated from the actual expenditures that were used in the vaccine delivery program in Indonesia. Results: The Vaccination Cost from the Study on Feasibility and Logistics of Vaccination School Age Children with Typhoid Vi-Vaccine conducted by DOMI project is not applicable for public vaccination program. The program might be feasible to be delivered only in private health sector settings.   Key words: Immunization expenditure, vaccine for typhoid fever, North Jakarta Indonesia

Oral vaccination with attenuated Salmonella choleraesuis C500 ...

African Journals Online (AJOL)

user

Marshall, 1983), and well known as the major gastro- duodenal ... The CagA is encoded in a pathogenicity island known as 'Cag PAI' and is .... HindIII to release the CagA fragment. The purified .... vaccine strain attenuated by chemical methods, which is .... pylori antigens is achieved using a non-toxic mutant of E. coli heat-.

Monitoring vaccine and non-vaccine HPV type prevalence in the post-vaccination era in women living in the Basilicata region, Italy.

Science.gov (United States)

Carozzi, Francesca; Puliti, Donella; Ocello, Cristina; Anastasio, Pasquale Silvio; Moliterni, Espedito Antonio; Perinetti, Emilia; Serradell, Laurence; Burroni, Elena; Confortini, Massimo; Mantellini, Paola; Zappa, Marco; Dominiak-Felden, Géraldine

2018-01-15

A large free-of-charge quadrivalent HPV (qHPV) vaccination program, covering four cohorts annually (women 11, 14, 17 and 24 years), has been implemented in Basilicata since 2007. This study evaluated vaccine and non-vaccine HPV prevalence 5-7 years post-vaccination program implementation in vaccinated and unvaccinated women. This population-based, cross-sectional study was conducted in the public screening centers of the Local Health Unit in Matera between 2012 and 2014. Cervical samples were obtained for Pap and HPV testing (HC2, LiPA Extra® assay) and participants completed a sociodemographic and behavioral questionnaire. Detailed HPV vaccination status was retrieved from the official HPV vaccine registry. HPV prevalence was described overall, by type and vaccination status. The association between HPV type-detection and risk/protective factors was studied. Direct vaccine protection (qHPV vaccine effectiveness [VE]), cross-protection, and type-replacement were evaluated in cohorts eligible for vaccination, by analyzing HPV prevalence of vaccine and non-vaccine types according to vaccination status. Overall, 2793 women (18-50 years) were included, 1314 of them having been in birth cohorts eligible for the HPV vaccination program (18- to 30-year-old women at enrolment). Among the latter, qHPV vaccine uptake was 59% (at least one dose), with 94% completing the schedule; standardized qHPV type prevalence was 0.6% in vaccinated versus 5.5% in unvaccinated women (P HPV, high-risk non-vaccine HPV, or any single non-vaccine type prevalence was observed between vaccinated and unvaccinated women. These results, conducted in a post-vaccine era, suggest a high qHPV VE and that a well-implemented catch-up vaccination program may be efficient in reducing vaccine-type infections in a real-world setting. No cross-protective effect or evidence of type-replacement was observed a few years after HPV vaccine introduction.

Experimental Salmonella typhimurium infections in rats. II. Active and passive immunization as protection against a lethal bacterial dose

DEFF Research Database (Denmark)

Hougen, H P; Jensen, E T; Klausen, B

1990-01-01

Immunization against a lethal dose of Salmonella typhimurium was studied in athymic and thymus-bearing LEW rats. Active immunization was performed with formalin-killed whole cell vaccine or sublethal infection prior to the lethal infection. After vaccination with killed bacteria the euthymic...... from immunized thymus grafted animals provided only limited protective effect, and treatment with cells from athymic animals had no effect. The study shows that although isogeneic thymus-grafted nude rats become resistent to reinfection with S. typhimurium, only large doses of spleen cells from...

The serologic response to Salmonella enteritidis and Salmonella typhimurium in experimentally infected chickens, followed by an indirect lipopolysaccharide enzyme-linked immunosorbent assay and bacteriologic examinations through a one-year period

DEFF Research Database (Denmark)

Skov, M.N.; Feld, Niels Christian; Carstensen, B.

2002-01-01

Three groups of 100 individually marked salmonella-free chickens were followed for a period of 53 wk. The chickens were infected as day olds by crop instillation of 101 colony-forming units: one group with Salmonella enteritidis and a second group with Salmonella typhimurium. A third group was kept...... in surveillance programs, in particular to detect flocks in early stages of infection before a measurable serologic response has been raised....

O-polysaccharide is important for Salmonella Pullorum survival in egg albumen, and virulence and colonization in chicken embryos.

Science.gov (United States)

Guo, Rongxian; Li, Zhuoyang; Jiao, Yang; Geng, Shizhong; Pan, Zhiming; Chen, Xiang; Li, Qiuchun; Jiao, Xinan

2017-10-01

The pathogen Salmonella Pullorum is the causative agent of persistent systemic infection of poultry, leading to economic losses in developing countries due to morbidity, mortality and reduction in egg production. These infections may result in vertical transmission to eggs or progeny. Limited information is available regarding the mechanisms involved in the survival of Salmonella Pullorum in egg albumen and developing chicken embryos. Hence, we investigated the role of O-polysaccharide in the contamination of eggs and the colonization of chicken embryos. Compared with the wild-type strain, the isogenic waaL mutant exhibited an O-antigen-deficient rough phenotype, and increased sensitivity to egg albumen and chicken serum, as well as reduced adherence to DF-1 cells. Infection with Salmonella Pullorum lacking O-polysaccharide resulted in significantly reduced embryo lethality and bacterial colonization. These results suggest that O-polysaccharide is essential for Salmonella Pullorum colonization in eggs, both post-lay and developing embryos. The chicken embryo infection model could be used to characterize the interaction between Salmonella Pullorum and developing embryos, and it will also contribute to the development of more rational vaccines to protect laying hens and embryos.

Influence of On-farm pig Salmonella status on Salmonella Shedding at Slaughter.

Science.gov (United States)

Casanova-Higes, A; Andrés-Barranco, S; Mainar-Jaime, R C

2017-08-01

The risk of Salmonella shedding among pigs at slaughter with regard to their previous on-farm Salmonella status was assessed in a group of pigs from a farm from NE of Spain. A total of 202 pigs that had been serologically monitored monthly during the fattening period and from which mesenteric lymph nodes (MLN) and faecal (SFEC) samples were collected at slaughter for Salmonella isolation were included. A repeated-measures anova was used to assess the relationship between mean OD% values during the fattening period and sampling time and bacteriology on MLN and SFEC. Pigs were also grouped into four groups, that is pigs seronegative during the fattening period and Salmonella negative in MLN (group A; n = 69); pigs seronegative during the fattening period but Salmonella positive in MLN (B; n = 36); pigs seropositive at least once and Salmonella positive in MLN (C; n = 50); and pigs seropositive at least once but Salmonella negative in (D; n = 47). Pigs shedding at slaughter seroconverted much earlier and showed much higher mean OD% values than non-shedders pigs. The proportion of Salmonella shedders in groups A and D was high and similar (26.1% and 29.8%, respectively), but significantly lower than that for groups B and C. The odds of shedding Salmonella for groups B and C were 4.8 (95% CI = 1.5-15.5) and 20.9 (3.7-118) times higher, respectively, when compared to A. It was concluded that a large proportion of Salmonella seronegative pigs may shed Salmonella at slaughter, which would be likely associated to previous exposure with contaminated environments (i.e. transport and lairage). For pigs already infected at farm, the likelihood of shedding Salmonella was much higher and may depend on whether the bacterium has colonized the MLN or not. The odds of shedding Salmonella spp. were always much higher for pigs in which Salmonella was isolated from MLN. © 2016 Blackwell Verlag GmbH.

Igg Subclasses Targeting the Flagella of Salmonella enterica Serovar Typhimurium Can Mediate Phagocytosis and Bacterial Killing

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Goh, Yun Shan; Armour, Kathryn L; Clark, Michael R; Grant, Andrew J; Mastroeni, Pietro

2016-01-01

Invasive non-typhoidal Salmonella are a common cause of invasive disease in immuno-compromised individuals and in children. Multi-drug resistance poses challenges to disease control, with a critical need for effective vaccines. Flagellin is an attractive vaccine candidate due to surface exposure and high epitope copy number, but its potential as a target for opsonophacytic antibodies is unclear. We examined the effect of targeting flagella with different classes of IgG on the interaction between Salmonella Typhimurium and a human phagocyte-like cell line, THP-1. We tagged the FliC flagellar protein with a foreign CD52 mimotope (TSSPSAD) and bacteria were opsonized with a panel of humanised CD52 antibodies with the same antigen-binding V-region, but different constant regions. We found that IgG binding to flagella increases bacterial phagocytosis and reduces viable intracellular bacterial numbers. Opsonisation with IgG3, followed by IgG1, IgG4, and IgG2, resulted in the highest level of bacterial uptake and in the highest reduction in the intracellular load of viable bacteria. Taken together, our data provide proof-of-principle evidence that targeting flagella with antibodies can increase the antibacterial function of host cells, with IgG3 being the most potent subclass. These data will assist the rational design of urgently needed, optimised vaccines against iNTS disease. PMID:27366588

Controversy and debate on dengue vaccine series-paper 1: review of a licensed dengue vaccine: inappropriate subgroup analyses and selective reporting may cause harm in mass vaccination programs.

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Dans, Antonio L; Dans, Leonila F; Lansang, Mary Ann D; Silvestre, Maria Asuncion A; Guyatt, Gordon H

2018-03-01

Severe life-threatening dengue fever usually occurs when a child is infected by dengue virus a second time. This is caused by a phenomenon called antibody-dependent enhancement (ADE). Since dengue vaccines can mimic a first infection in seronegative children (those with no previous infection), a natural infection later in life could lead to severe disease. The possibility that dengue vaccines can cause severe dengue through ADE has led to serious concern regarding the safety of mass vaccination programs. A published meta-analysis addressed this safety issue for a new vaccine against dengue fever-Dengvaxia. The trials in this meta-analysis have been used to campaign for mass vaccination programs in developing countries. We discuss the results of this paper and point out problems in the analyses. Reporting the findings in an Asian trial (CYD14), the authors show a sevenfold rise in one outcome-hospitalization for dengue fever in children <5 years old. However, they fail to point out two signals of harm for another outcome-hospitalization for severe dengue fever (as confirmed by an independent data monitoring committee): 1. In children younger than 9 years, the relative risk was 8.5 (95% confidence interval [CI]: 0.5, 146.8), and 2. In the overall study group, the relative risk was 5.5 (95% CI: 0.9, 33). The authors conduct a subgroup analysis to support claims that the vaccine is probably safe among children aged 9 years or more. This subgroup analysis has limited credibility because: (1) it was a post hoc analysis; (2) it was one of a large number of subgroup analyses; (3) the test of interaction was not reported, but was insignificant (P = 0.14); and (4) there is no biological basis for a threshold age of 9 years. The more likely explanation for the higher risk in younger children is ADE, that is, more frequent seronegativity, rather than age itself. The selective reporting and inappropriate subgroup claims mask the potential harm of dengue mass vaccination

Changing Attitudes Toward Influenza Vaccination in U.S. Kidney Transplant Programs Over the Past Decade

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Kadambi, Pradeep V.; Harland, Robert C.; Thistlethwaite, J. Richard; West, Bradford L.; Udani, Suneel; Poduval, Rajiv; Josephson, Michelle A.

2010-01-01

Background and objectives: Influenza infection in transplant recipients is often associated with significant morbidity. Surveys were conducted in 1999 and 2009 to find out if the influenza vaccination practices in the U.S. transplant programs had changed over the past 10 years. Design, setting, participants, & measurements: In 1999, a survey of the 217 United Network for Organ Sharing-certified kidney and kidney-pancreas transplant centers in the U.S. was conducted regarding their influenza vaccination practice patterns. A decade later, a second similar survey of 239 transplant programs was carried out. Results: The 2009 respondents, compared with 1999, were more likely to recommend vaccination for kidney (94.5% versus 84.4%, P = 0.02) and kidney-pancreas recipients (76.8% versus 48.5%, P < 0.001), family members of transplant recipients (52.5% versus 21.0%, P < 0.001), and medical staff caring for transplant patients (79.6% versus 40.7%, P < 0.001). Physicians and other members of the transplant team were more likely to have been vaccinated in 2009 compared with 1999 (84.2% versus 62.3% of physicians, P < 0.001 and 91.2% versus 50.3% of nonphysicians, P < 0.001). Conclusions: Our study suggests a greater adoption of the Centers for Disease Control and Prevention influenza vaccination guidelines by U.S. transplant programs in vaccinating solid-organ transplant recipients, close family contacts, and healthcare workers. PMID:20595695

Expanding Free School-based Human Papilloma Virus (HPV Vaccination Programs to Include School-aged Males in Nova Scotia, Canada

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Hannah Krater-Melamed

2017-06-01

Full Text Available Bill 70 (HPV Vaccine Act was presented to the Nova Scotia House of Assembly with the aim of expanding the current Nova Scotia school-based HPV vaccination program to include males. In recent years, increased awareness of HPV and HPV-caused cancers has led to the implementation of school-based female HPV vaccination programs across Canada. Changing guidelines, based on recent evidence, suggest that males should also be included in these programs. Program expansion to include males aims to reduce the prevalence of HPV-causing cancers and their ensuing costs, to promote equal access to healthcare services, and to make Nova Scotia a leader in HPV prevention. Support from the Canadian public and high profile political actors along with pressure from other provinces and interest groups, including the Society of Obstetricians and Gynaecologists of Canada, influenced the passing of the HPV Vaccine Act. In order to implement this reform, the provincial financial commitment to the previous HPV program was expanded to cover the cost of male vaccination.

POTENSI Salmonella typhi YANG DILEMAHKAN DENGAN SINAR ULTRAVIOLET SEBAGAI VAKSIN ALTERNATIF

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Andreas Putro Ragil Santoso

2016-03-01

Full Text Available Salmonella typhi is a Gram-negative intracellular bacterium and causes typhoid fever in humans. The success rate of Berma Vivotif Ty21a vaccine in Indonesia is only 33-66%, while in other countries have been reached up to 100%. The research was conducted in order to determine the potency of local isolate bacteria to stimulate the immune response and the impact of different exposure frequencies on the immune response and the different immune response time when administered by UV-inactivated vaccine.. The results showed that the antibody titer of local isolates irradiated by UV light 10x was 88.76 ± 33.06 IU/mL at week 4 with the lowest antibody titer values about 11.15 ± 9.18 IU/mL was found in the negative control.

Eleventh CRL-Salmonella interlaboratory comparison study on typing of Salmonella spp.

NARCIS (Netherlands)

Berk PA; Maas HME; de Pinna E; Mooijman KA; MGB

2006-01-01

Het elfde ringonderzoek voor de typering van Salmonella werd in maart 2006 georganiseerd door het Communautair Referentie Laboratorium voor Salmonella (CRL-Salmonella, Bilthoven, Nederland) in samenwerking met de Health Protection Agency (HPA, Londen, Verenigd Koninkrijk). 26 Nationale Referentie

Presentation of life-threatening invasive nontyphoidal Salmonella disease in Malawian children: A prospective observational study.

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MacLennan, Calman A; Msefula, Chisomo L; Gondwe, Esther N; Gilchrist, James J; Pensulo, Paul; Mandala, Wilson L; Mwimaniwa, Grace; Banda, Meraby; Kenny, Julia; Wilson, Lorna K; Phiri, Amos; MacLennan, Jenny M; Molyneux, Elizabeth M; Molyneux, Malcolm E; Graham, Stephen M

2017-12-01

Nontyphoidal Salmonellae commonly cause invasive disease in African children that is often fatal. The clinical diagnosis of these infections is hampered by the absence of a clear clinical syndrome. Drug resistance means that empirical antibiotic therapy is often ineffective and currently no vaccine is available. The study objective was to identify risk factors for mortality among children presenting to hospital with invasive Salmonella disease in Africa. We conducted a prospective study enrolling consecutive children with microbiologically-confirmed invasive Salmonella disease admitted to Queen Elizabeth Central Hospital, Blantyre, in 2006. Data on clinical presentation, co-morbidities and outcome were used to identify children at risk of inpatient mortality through logistic-regression modeling. Over one calendar year, 263 consecutive children presented with invasive Salmonella disease. Median age was 16 months (range 0-15 years) and 52/256 children (20%; 95%CI 15-25%) died. Nontyphoidal serovars caused 248/263 (94%) of cases. 211/259 (81%) of isolates were multi-drug resistant. 251/263 children presented with bacteremia, 6 with meningitis and 6 with both. Respiratory symptoms were present in 184/240 (77%; 95%CI 71-82%), 123/240 (51%; 95%CI 45-58%) had gastrointestinal symptoms and 101/240 (42%; 95%CI 36-49%) had an overlapping clinical syndrome. Presentation at Salmonella disease in Malawi is characterized by high mortality and prevalence of multi-drug resistant isolates, along with non-specific presentation. Young infants, children with dyspnea and HIV-infected children bear a disproportionate burden of the Salmonella-associated mortality in Malawi. Strategies to improve prevention, diagnosis and management of invasive Salmonella disease should be targeted at these children.

Tenth CRL-Salmonella interlaboratory comparison study on typing of Salmonella spp.

NARCIS (Netherlands)

Korver H; Maas HME; Ward LR; Mevius DJ; Mooijman KA; MGB

2006-01-01

Het tiende ringonderzoek voor de typering van Salmonella werd in maart 2005 georganiseerd door het Communautair Referentie Laboratorium voor Salmonella (CRL-Salmonella, Bilthoven, Nederland) in samenwerking met de Health Protection Agency (HPA, Londen, Verenigd Koninkrijk) en het Centraal Instituut

[Use of new immunoglobulin isotype-specific ELISA-systems to detect Salmonella infections in pigs].

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Ehlers, Joachim; Alt, Michael; Trepnau, Daniela; Lehmann, Jörg

2006-01-01

In Germany, the program for controlling salmonella infections in pigs is based on tests detecting salmonella-lipopolysaccharide (LPS) induced antibodies in meat-juice or blood. These conventional tests which are based on the technology of enzyme-linked immunosorbent assay (ELISA) detect exclusively or mainly immunoglobulin(lg)G antibodies. Meanwhile, novel ELISA systems (WCE-ELISA, 3-Isotype-Screening-ELISA) have been developed, which additionally detect the antibody classes IgM and IgA.This fact enables the registration of fresh salmonella infections (starting with day 5 p.i.) and thus, the distinction between early and older infections. The results show that animals with early salmonella infections appear significantly more often in herds with a high than with a low prevalence. With the newly developed tests this group of animals can be detected much more efficiently and precisely than with the tests used so far. Due to their clearly improved sensitivity the application of the WCE-ELISA and the 3-Isotype-Screening-ELISA in terms of the QS-Salmonella-Monitoring program can therefore significantly improve the selection of farms with potential salmonella excretors. Additionally, the WCE-ELISA can be applied very suitable for the examination of individual animals.

Prevention of HPV-related cancers in Norway: cost-effectiveness of expanding the HPV vaccination program to include pre-adolescent boys.

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Burger, Emily A; Sy, Stephen; Nygård, Mari; Kristiansen, Ivar S; Kim, Jane J

2014-01-01

Increasingly, countries have introduced female vaccination against human papillomavirus (HPV), causally linked to several cancers and genital warts, but few have recommended vaccination of boys. Declining vaccine prices and strong evidence of vaccine impact on reducing HPV-related conditions in both women and men prompt countries to reevaluate whether HPV vaccination of boys is warranted. A previously-published dynamic model of HPV transmission was empirically calibrated to Norway. Reductions in the incidence of HPV, including both direct and indirect benefits, were applied to a natural history model of cervical cancer, and to incidence-based models for other non-cervical HPV-related diseases. We calculated the health outcomes and costs of the different HPV-related conditions under a gender-neutral vaccination program compared to a female-only program. Vaccine price had a decisive impact on results. For example, assuming 71% coverage, high vaccine efficacy and a reasonable vaccine tender price of $75 per dose, we found vaccinating both girls and boys fell below a commonly cited cost-effectiveness threshold in Norway ($83,000/quality-adjusted life year (QALY) gained) when including vaccine benefit for all HPV-related diseases. However, at the current market price, including boys would not be considered 'good value for money.' For settings with a lower cost-effectiveness threshold ($30,000/QALY), it would not be considered cost-effective to expand the current program to include boys, unless the vaccine price was less than $36/dose. Increasing vaccination coverage to 90% among girls was more effective and less costly than the benefits achieved by vaccinating both genders with 71% coverage. At the anticipated tender price, expanding the HPV vaccination program to boys may be cost-effective and may warrant a change in the current female-only vaccination policy in Norway. However, increasing coverage in girls is uniformly more effective and cost-effective than expanding

Prevention of HPV-related cancers in Norway: cost-effectiveness of expanding the HPV vaccination program to include pre-adolescent boys.

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Emily A Burger

Full Text Available BACKGROUND: Increasingly, countries have introduced female vaccination against human papillomavirus (HPV, causally linked to several cancers and genital warts, but few have recommended vaccination of boys. Declining vaccine prices and strong evidence of vaccine impact on reducing HPV-related conditions in both women and men prompt countries to reevaluate whether HPV vaccination of boys is warranted. METHODS: A previously-published dynamic model of HPV transmission was empirically calibrated to Norway. Reductions in the incidence of HPV, including both direct and indirect benefits, were applied to a natural history model of cervical cancer, and to incidence-based models for other non-cervical HPV-related diseases. We calculated the health outcomes and costs of the different HPV-related conditions under a gender-neutral vaccination program compared to a female-only program. RESULTS: Vaccine price had a decisive impact on results. For example, assuming 71% coverage, high vaccine efficacy and a reasonable vaccine tender price of $75 per dose, we found vaccinating both girls and boys fell below a commonly cited cost-effectiveness threshold in Norway ($83,000/quality-adjusted life year (QALY gained when including vaccine benefit for all HPV-related diseases. However, at the current market price, including boys would not be considered 'good value for money.' For settings with a lower cost-effectiveness threshold ($30,000/QALY, it would not be considered cost-effective to expand the current program to include boys, unless the vaccine price was less than $36/dose. Increasing vaccination coverage to 90% among girls was more effective and less costly than the benefits achieved by vaccinating both genders with 71% coverage. CONCLUSIONS: At the anticipated tender price, expanding the HPV vaccination program to boys may be cost-effective and may warrant a change in the current female-only vaccination policy in Norway. However, increasing coverage in girls is

Prevention of HPV-Related Cancers in Norway: Cost-Effectiveness of Expanding the HPV Vaccination Program to Include Pre-Adolescent Boys

Science.gov (United States)

Burger, Emily A.; Sy, Stephen; Nygård, Mari; Kristiansen, Ivar S.; Kim, Jane J.

2014-01-01

Background Increasingly, countries have introduced female vaccination against human papillomavirus (HPV), causally linked to several cancers and genital warts, but few have recommended vaccination of boys. Declining vaccine prices and strong evidence of vaccine impact on reducing HPV-related conditions in both women and men prompt countries to reevaluate whether HPV vaccination of boys is warranted. Methods A previously-published dynamic model of HPV transmission was empirically calibrated to Norway. Reductions in the incidence of HPV, including both direct and indirect benefits, were applied to a natural history model of cervical cancer, and to incidence-based models for other non-cervical HPV-related diseases. We calculated the health outcomes and costs of the different HPV-related conditions under a gender-neutral vaccination program compared to a female-only program. Results Vaccine price had a decisive impact on results. For example, assuming 71% coverage, high vaccine efficacy and a reasonable vaccine tender price of $75 per dose, we found vaccinating both girls and boys fell below a commonly cited cost-effectiveness threshold in Norway ($83,000/quality-adjusted life year (QALY) gained) when including vaccine benefit for all HPV-related diseases. However, at the current market price, including boys would not be considered ‘good value for money.’ For settings with a lower cost-effectiveness threshold ($30,000/QALY), it would not be considered cost-effective to expand the current program to include boys, unless the vaccine price was less than $36/dose. Increasing vaccination coverage to 90% among girls was more effective and less costly than the benefits achieved by vaccinating both genders with 71% coverage. Conclusions At the anticipated tender price, expanding the HPV vaccination program to boys may be cost-effective and may warrant a change in the current female-only vaccination policy in Norway. However, increasing coverage in girls is uniformly more

Salmonella enterica serovar Choleraesuis vector delivering SaoA antigen confers protection against Streptococcus suis serotypes 2 and 7 in mice and pigs.

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Li, Yu-An; Ji, Zhenying; Wang, Xiaobo; Wang, Shifeng; Shi, Huoying

2017-12-21

Streptococcus suis is one of the major pathogens that cause economic losses in the swine industry worldwide. However, current bacterins only provide limited prophylactic protection in the field. An ideal vaccine against S. suis should protect pigs against the clinical diseases caused by multiple serotypes, or at least protect against the dominant serotype in a given geographic region. A new recombinant Salmonella enterica serotype Choleraesuis vaccine vector, rSC0011, that is based on the regulated delayed attenuation system and regulated delayed antigen synthesis system, was developed recently. In this study, an improved recombinant attenuated Salmonella Choleraesuis vector, rSC0016, was developed by incorporating a sopB mutation to ensure adequate safety and maximal immunogenicity. In the spleens of mice, rSC0016 colonized less than rSC0011. rSC0016 and rSC0011 colonized similarly in Peyer's patches of mice. The recombinant vaccine rSC0016(pS-SaoA) induced stronger cellular, humoral, and mucosal immune responses in mice and swine against SaoA, a conserved surface protein that is present in many S. suis serotypes, than did rSC0011(pS-SaoA) without sopB or rSC0018(pS-SaoA), which is an avirulent, chemically attenuated vaccine strain. rSC0016(pS-SaoA) provided 100% protection against S. suis serotype 2 in mice and pigs, and full cross-protection against SS7 in pigs. This new vaccine vector provides a foundation for the development of a universal vaccine against multiple serotypes of S. suis in pigs.

Evaluation of respiratory route as a viable portal of entry for Salmonella in poultry

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Kallapura G

2014-08-01

system as essentially one large interconnected network that shares information distally, since understanding of this sort of communication between mucosal sites is fundamental to establish the next phase of disease characterization, and perhaps immunization and vaccine development. Further characterization of the respiratory tract with regard to transmission of Salmonella under field conditions may be of critical importance in developing interventional strategies to reduce transmission of this important zoonotic pathogen in poultry. Keywords: Salmonella, respiratory route, portal of entry, systemic dissemination

Role of Environmental Factors in Shaping Spatial Distribution of Salmonella enterica Serovar Typhi, Fiji.

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de Alwis, Ruklanthi; Watson, Conall; Nikolay, Birgit; Lowry, John H; Thieu, Nga Tran Vu; Van, Tan Trinh; Ngoc, Dung Tran Thi; Rawalai, Kitione; Taufa, Mere; Coriakula, Jerimaia; Lau, Colleen L; Nilles, Eric J; Edmunds, W John; Kama, Mike; Baker, Stephen; Cano, Jorge

2018-02-01

Fiji recently experienced a sharp increase in reported typhoid fever cases. To investigate geographic distribution and environmental risk factors associated with Salmonella enterica serovar Typhi infection, we conducted a cross-sectional cluster survey with associated serologic testing for Vi capsular antigen-specific antibodies (a marker for exposure to Salmonella Typhi in Fiji in 2013. Hotspots with high seroprevalence of Vi-specific antibodies were identified in northeastern mainland Fiji. Risk for Vi seropositivity increased with increased annual rainfall (odds ratio [OR] 1.26/quintile increase, 95% CI 1.12-1.42), and decreased with increased distance from major rivers and creeks (OR 0.89/km increase, 95% CI 0.80-0.99) and distance to modeled flood-risk areas (OR 0.80/quintile increase, 95% CI 0.69-0.92) after being adjusted for age, typhoid fever vaccination, and home toilet type. Risk for exposure to Salmonella Typhi and its spatial distribution in Fiji are driven by environmental factors. Our findings can directly affect typhoid fever control efforts in Fiji.

A novel Salmonella serovar isolated from Peregrine Falcon (Falco peregrinus nestlings in Sweden: Salmonella enterica enterica serovar Pajala (Salmonella Pajala

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Jorge Hernández

2012-08-01

Full Text Available A novel Salmonella serovar was isolated from Peregrine falcon (Falco peregrinus nestlings in northern Sweden in 2006. Three isolates of the same clone was retrieved from three falcon siblings and characterized as Salmonella enterica sub-species enterica: O-phase 13, 23:-: e, n, z 15 and the H-phase was not present. We propose the geographical name Salmonella enterica, sub-species enterica serovar Pajala to this novel Salmonella.

Measuring the performance of vaccination programs using cross-sectional surveys: a likelihood framework and retrospective analysis.

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Justin Lessler

2011-10-01

Full Text Available The performance of routine and supplemental immunization activities is usually measured by the administrative method: dividing the number of doses distributed by the size of the target population. This method leads to coverage estimates that are sometimes impossible (e.g., vaccination of 102% of the target population, and are generally inconsistent with the proportion found to be vaccinated in Demographic and Health Surveys (DHS. We describe a method that estimates the fraction of the population accessible to vaccination activities, as well as within-campaign inefficiencies, thus providing a consistent estimate of vaccination coverage.We developed a likelihood framework for estimating the effective coverage of vaccination programs using cross-sectional surveys of vaccine coverage combined with administrative data. We applied our method to measles vaccination in three African countries: Ghana, Madagascar, and Sierra Leone, using data from each country's most recent DHS survey and administrative coverage data reported to the World Health Organization. We estimate that 93% (95% CI: 91, 94 of the population in Ghana was ever covered by any measles vaccination activity, 77% (95% CI: 78, 81 in Madagascar, and 69% (95% CI: 67, 70 in Sierra Leone. "Within-activity" inefficiencies were estimated to be low in Ghana, and higher in Sierra Leone and Madagascar. Our model successfully fits age-specific vaccination coverage levels seen in DHS data, which differ markedly from those predicted by naïve extrapolation from country-reported and World Health Organization-adjusted vaccination coverage.Combining administrative data with survey data substantially improves estimates of vaccination coverage. Estimates of the inefficiency of past vaccination activities and the proportion not covered by any activity allow us to more accurately predict the results of future activities and provide insight into the ways in which vaccination programs are failing to meet their

Is it Right Time to Introduce Mumps Vaccine in Indias Universal Immunization Program?

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Vaidya, S R; Hamde, V S

2016-06-08

Measles, mumps and rubella are vaccine preventable diseases. However, morbidity and mortality due to these diseases remain largely unnoticed in India. Measles has received much attention; mumps and rubella still need to garner attention. According to the World Health Organization, near-elimination of mumps could be achieved by maintaining high vaccine coverage using a two-dose strategy. However, Government of India has not yet decided on mumps vaccine. In this review, we have reviewed sero-prevalence studies, vaccine studies, outbreak investigations, virus isolation and virus genotyping studies on mumps. Overall, mumps seems to be a significant public health problem in India, but does not garner attention due to the absence of a surveillance and documentation system. Thus, inclusion of mumps antigen in the Universal immunization program would have added advantages, the economic burden imposed by the cost of the vaccine offset by a reduction in disease burden.

Managing control programs for ovine caseous lymphadenitis and paratuberculosis in Australia, and the need for persistent vaccination

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Windsor PA

2014-03-01

Full Text Available Peter Andrew WindsorFaculty of Veterinary Science, University of Sydney, Camden, NSW, AustraliaAbstract: Ovine caseous lymphadenitis (CLA and ovine Johne's disease (OJD or paratuberculosis have been serious diseases in the Australian sheep industry, mainly causing losses from abattoir condemnations from CLA or mortalities on the farm from OJD. CLA is now a disease of minimal concern, with clinical cases reported rarely. Although OJD continues to spread through parts of the sheep population, the catastrophic losses in flocks occurring prior to the introduction of vaccination are now uncommon. Change-management factors relevant to the improvements in both prevalence and producer concerns for CLA and OJD were examined, including drivers and motivation for change, resistance to change, knowledge management, farming system dimensions and leadership. Although extension programs addressing disease risk factors are likely to be of relevance to improved knowledge and attitudes towards disease risk management of producers, improvements in disease-control practices were considered largely attributable to the introduction of vaccination programs for CLA in 1983 and OJD in 2002. Inclusion of the CLA antigen within clostridial vaccines (“6 in 1” vaccine enabled routine annual CLA vaccination to occur in an increasing proportion of the national flock, with estimates of CLA prevalence suggesting a decline from 26% in 1995 to 5.2% in 2009. Encouraging the routine vaccination of lambs for OJD (Gudair vaccine in infected flocks to reduce or avoid losses significantly reduced the within-flock prevaccination–postvaccination median prevalence from 2.72% to 0.72%, based on estimated shedding rates of Mycobacterium avium subsp. paratuberculosis determined by pooled fecal culture in 37 infected flocks vaccinating for at least 5 years. Although persistent use of CLA vaccine is a convenient intervention for producers, promoting the persistent use of OJD vaccination

Economic impact of dengue illness and the cost-effectiveness of future vaccination programs in Singapore.

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Luis R Carrasco

2011-12-01

Full Text Available BACKGROUND: Dengue illness causes 50-100 million infections worldwide and threatens 2.5 billion people in the tropical and subtropical regions. Little is known about the disease burden and economic impact of dengue in higher resourced countries or the cost-effectiveness of potential dengue vaccines in such settings. METHODS AND FINDINGS: We estimate the direct and indirect costs of dengue from hospitalized and ambulatory cases in Singapore. We consider inter alia the impacts of dengue on the economy using the human-capital and the friction cost methods. Disease burden was estimated using disability-adjusted life years (DALYs and the cost-effectiveness of a potential vaccine program was evaluated. The average economic impact of dengue illness in Singapore from 2000 to 2009 in constant 2010 US$ ranged between $0.85 billion and $1.15 billion, of which control costs constitute 42%-59%. Using empirically derived disability weights, we estimated an annual average disease burden of 9-14 DALYs per 100 000 habitants, making it comparable to diseases such as hepatitis B or syphilis. The proportion of symptomatic dengue cases detected by the national surveillance system was estimated to be low, and to decrease with age. Under population projections by the United Nations, the price per dose threshold for which vaccines stop being more cost-effective than the current vector control program ranged from $50 for mass vaccination requiring 3 doses and only conferring 10 years of immunity to $300 for vaccination requiring 2 doses and conferring lifetime immunity. The thresholds for these vaccine programs to not be cost-effective for Singapore were $100 and $500 per dose respectively. CONCLUSIONS: Dengue illness presents a serious economic and disease burden in Singapore. Dengue vaccines are expected to be cost-effective if reasonably low prices are adopted and will help to reduce the economic and disease burden of dengue in Singapore substantially.

Economic analysis of a herpes zoster vaccination program in 19 affiliated supermarket pharmacies.

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Hedden, Megan A; Kuehl, Peggy G; Liu, Yifei

2014-01-01

To examine the economic impact of providing herpes zoster vaccine (ZOS) in 19 affiliated supermarket pharmacies in a midwestern metropolitan area from the perspective of the pharmacy and to identify factors associated with greater rates of vaccine delivery and profitability. 19 affiliated supermarket pharmacies in the Kansas City metropolitan area. Immunizations with ZOS were expanded from 2 pharmacies to all 19 affiliated pharmacies. Various methods to promote the vaccine were used, including personal selling, store signage, and circular ads. In addition to a broad perspective pharmacoeconomic model, a localized perspective model is proposed to determine profitability for the service. Factors associated with greater success in vaccine delivery and profitability were identified. Net financial gains or losses were calculated for each vaccine administered for each of the 19 pharmacies and for the entire supermarket chain. 662 vaccines were given during the study period, accounting for 6.7% of all eligible patients. The profit per vaccine averaged $9.60 (5.7%) and $28.37 (18.9%) using the broad and localized perspective models, respectively. Success of the ZOS program was demonstrated using both models. Certain factors correlated with greater profits when using the localized perspective model.

Carriage of Streptococcus pneumoniae 3 Years after Start of Vaccination Program, the Netherlands

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Spijkerman, J.; van Gils, E.J.M.; Veenhoven, R.H.; Hak, E.; Yzerman, E.P.F.; van den Ende, A.; Wijmenga-Monsuur, A.J.; van den Dobbelsteen, G.P.J.M.; Sanders, E.A.M.

2011-01-01

To evaluate the effectiveness of the 7-valent pneumococcal conjugate vaccine (PCV7) program, we conducted a cross-sectional observational study on nasopharyngeal carriage of Streptococcus pneumoniae 3 years after implementation of the program in the Netherlands. We compared pneumococcal serotypes in

10 year assessment of infant hepatitis B vaccination program, in the Loyalty Islands (New Caledonia).

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Berlioz-Arthaud, Alain; Perolat, Philippe; Buisson, Yves

2003-06-20

To evaluate the decrease of hepatitis B prevalence in New Caledonia 10 years after the implementation of a neonatal vaccination program and discuss the need of any booster in preadolescents. A survey was conducted in the Loyalty Islands, involving 593 children aged 8-11 years. Serological profiles were determined using three parameters: antibodies to core and surface antigens and HBs Ag. The vaccine coverage rate is 93 and 89% of the children are protected against hepatitis B. However, 8% of them did have contact with the virus and 1.3% are carriers. Thirty-eight percent of the vaccinated children had their first injection later than the age of 3 months. This study attests that the neonatal immunisation is accepted and followed. The prevalence reduction is not as great as expected, probably due to excess delay in primary vaccination. Hepatitis B eradication could be achieved in New Caledonia by starting immunisation at birth, and by implementing a global catch-up program among preadolescents.

Systematic review of economic evaluations of vaccination programs in mainland China: Are they sufficient to inform decision making?

Science.gov (United States)

Pan, Xiong-Fei; Griffiths, Ulla K; Pennington, Mark; Yu, Hongjie; Jit, Mark

2015-11-17

The purpose of the study was to systematically review economic evaluations of vaccine programs conducted in mainland China. We searched for economic evaluations of vaccination in China published prior to August 3, 2015 in eight English-language and three Chinese-language databases. Each article was appraised against the 19-item Consensus on Health Economic Criteria list (CHEC-list). We found 23 papers evaluating vaccines against hepatitis B (8 articles), Streptococcus pneumoniae (5 articles), human papillomavirus (3 articles), Japanese encephalitis (2 articles), rotavirus (2 articles), hepatitis A (1 article), Enterovirus 71 (1 article) and influenza (1 article). Studies conformed to a mean of 12 (range: 6-18) items in the CHEC-list criteria. Five of six Chinese-language articles conformed to fewer than half of the 19 criteria items. The main criteria that studies failed to conform to included: inappropriate measurement (20 articles) and valuation (18 articles) of treatment and/or vaccination costs, no discussion about distributional implications (18 articles), missing major health outcomes (14 articles), no discussion about generalizability to other contexts (14 articles), and inadequate sensitivity analysis (13 articles). In addition, ten studies did not include major cost components of vaccination programs, and nine did not report outcomes in terms of life years even in cases where QALYs or DALYs were calculated. Only 13 studies adopted a societal perspective for analysis. All studies concluded that the appraised vaccination programs were cost-effective except for one evaluation of universal 7-valent pneumococcal conjugate vaccine (PCV-7) in children. However, three of the five studies on PCV-7 showed poor overall quality, and the number of studies on vaccines other than hepatitis B vaccine and PCV-7 was limited. In conclusion, major methodological flaws and reporting problems exist in current economic evaluations of vaccination programs in China. Local

Relationship among fecal coliforms, Escherichia coli, and Salmonella spp. in shellfish.

Science.gov (United States)

Hood, M A; Ness, G E; Blake, N J

1983-01-01

The relationship of fecal coliforms, Escherichia coli, and Salmonella spp. was examined in freshly harvested and stored shellfish. In 16 of 40 freshly collected oyster samples, fecal coliform levels were above the recommended wholesale level suggested by the National Shellfish Sanitation Program (less than or equal to 230/100 g), and Salmonella spp. were present in three of these samples. Salmonella spp. were not, however, present in any sample containing less than 230 fecal coliforms per 100 g. Analysis of the data suggests that low fecal coliform levels in both fresh and stored oysters are good indicators of the absence of Salmonella spp., but that high levels of fecal coliforms are somewhat limited in predicting the presence of Salmonella spp. E. coli levels correlated very strongly with fecal coliform levels in both fresh and stored oysters and clams, suggesting that there is no advantage in replacing fecal coliforms with E. coli as an indicator of shellfish quality.

Targeted outreach hepatitis B vaccination program in high-risk adults: The fundamental challenge of the last mile.

Science.gov (United States)

Mangen, M-J J; Stibbe, H; Urbanus, A; Siedenburg, E C; Waldhober, Q; de Wit, G A; van Steenbergen, J E

2017-05-31

The aim of this study was to evaluate the cost-effectiveness of the on-going decentralised targeted hepatitis B vaccination program for behavioural high-risk groups operated by regional public health services in the Netherlands since 1-November-2002. Target groups for free vaccination are men having sex with men (MSM), commercial sex workers (CSW) and hard drug users (HDU). Heterosexuals with a high partner change rate (HRP) were included until 1-November-2007. Based on participant, vaccination and serology data collected up to 31-December-2012, the number of participants and program costs were estimated. Observed anti-HBc prevalence was used to estimate the probability of susceptible individuals per risk-group to become infected with hepatitis B virus (HBV) in their remaining life. We distinguished two time-periods: 2002-2006 and 2007-2012, representing different recruitment strategies and target groups. Correcting for observed vaccination compliance, the number of future HBV-infections avoided was estimated per risk-group. By combining these numbers with estimates of life-years lost, quality-of-life losses and healthcare costs of HBV-infections - as obtained from a Markov model-, the benefit of the program was estimated for each risk-group separately. The overall incremental cost-effectiveness ratio of the program was €30,400/QALY gained, with effects and costs discounted at 1.5% and 4%, respectively. The program was more cost-effective in the first period (€24,200/QALY) than in the second period (€42,400/QALY). In particular, the cost-effectiveness for MSM decreased from €20,700/QALY to €47,700/QALY. This decentralised targeted HBV-vaccination program is a cost-effective intervention in certain unvaccinated high-risk adults. Saturation within the risk-groups, participation of individuals with less risky behaviour, and increased recruitment investments in the second period made the program less cost-effective over time. The project should therefore

Persistence of salmonella Typhimurium in Nopal

Science.gov (United States)

Having documented information available on the capability of Salmonella to remain in the cladode tissue it is important to understand the role of nopal on the lifecycle of enteropathogenic bacteria in humans, as well as for management and control programs of theses pathogens in plants. Because of th...

A Randomised Trial Evaluating the Safety and Immunogenicity of the Novel Single Oral Dose Typhoid Vaccine M01ZH09 in Healthy Vietnamese Children

NARCIS (Netherlands)

Tran, T.H.; Nguyen, T.D.; Nguyen, T.T.; Ninh, T.T.V.; Tran, N.B.C.; Nguyen, V.M.H.; Tran, T.T.N.; Cao, T.T.; Pham, V.M.; Nguyen, T.C.B.; Tran, T.D.H.; Pham, V.T.; To, S.D.; Campbell, J.I.; Stockwell, E.; Schultsz, C.; Simmons, C.P.; Glover, C.; Lam, W.; Marques, F.; May, J.P.; Upton, A.; Budhram, R.; Dougan, G.; Farrar, J.; Nguyen, V.V.C.; Dolecek, C.

2010-01-01

Background: The emergence of drug resistant typhoid fever is a major public health problem, especially in Asia. An oral single dose typhoid vaccine would have major advantages. M01ZH09 is a live oral single dose candidate typhoid vaccine containing Salmonella enterica serovar Typhi (Ty2 aroC(-)

Adolescent Attitudes toward Influenza Vaccination and Vaccine Uptake in a School-Based Influenza Vaccination Intervention: A Mediation Analysis

Science.gov (United States)

Painter, Julia E.; Sales, Jessica M.; Pazol, Karen; Wingood, Gina M.; Windle, Michael; Orenstein, Walter A.; DiClemente, Ralph J.

2011-01-01

Background: School-based vaccination programs may provide an effective strategy to immunize adolescents against influenza. This study examined whether adolescent attitudes toward influenza vaccination mediated the relationship between receipt of a school-based influenza vaccination intervention and vaccine uptake. Methods: Participants were…

An economic evaluation of the use of Japanese encephalitis vaccine in the expanded program of immunization of Guizhou province, China.

Science.gov (United States)

Yin, Zundong; Beeler Asay, Garrett R; Zhang, Li; Li, Yixing; Zuo, Shuyan; Hutin, Yvan J; Ning, Guijun; Sandhu, Hardeep S; Cairns, Lisa; Luo, Huiming

2012-08-10

Historically, China's Japanese encephalitis vaccination program was a mix of household purchase of vaccine and government provision of vaccine in some endemic provinces. In 2006, Guizhou, a highly endemic province in South West China, integrated JE vaccine into the provincial Expanded Program on Immunization (EPI); later, in 2007 China fully integrated 28 provinces into the national EPI, including Guizhou, allowing for vaccine and syringe costs to be paid at the national level. We conducted a retrospective economic analysis of JE integration into EPI in Guizhou province. We modeled two theoretical cohorts of 100,000 persons for 65 years; one using JE live-attenuated vaccine in EPI (first dose: 95% coverage and 94.5% efficacy; second dose: 85% coverage and 98% efficacy) and one not. We assumed 60% sensitivity of surveillance for reported JE rates, 25% case fatality, 30% chronic disability and 3% discounting. We reviewed acute care medical records and interviewed a sample of survivors to estimate direct and indirect costs of illness. We reviewed the EPI offices expenditures in 2009 to estimate the average Guizhou program cost per vaccine dose. Use of JE vaccine in EPI for 100,000 persons would cost 434,898 US$ each year (46% of total cost due to vaccine) and prevent 406 JE cases, 102 deaths, and 122 chronic disabilities (4554 DALYs). If we ignore future cost savings and only use EPI program cost, the program would cost 95.5 US$/DALY, less than China Gross Domestic Product per capita in 2009 (3741 US$). From a cost-benefit perspective taking into account future savings, use of JE vaccine in EPI for a 100,000-person cohort would lead to savings of 1,591,975 US$ for the health system and 11,570,989 US$ from the societal perspective. In Guizhou, China, use of JE vaccine in EPI is a cost effective investment. Furthermore, it would lead to savings for the health system and society. Copyright © 2012 Elsevier Ltd. All rights reserved.

Advanced Oxidation Process sanitization of hatching eggs reduces Salmonella in broiler chicks.

Science.gov (United States)

Rehkopf, A C; Byrd, J A; Coufal, C D; Duong, T

2017-10-01

The microbial quality of eggs entering the hatchery is an important critical control point for biosecurity, pathogen reduction, and food safety programs in poultry production. Developing interventions to reduce Salmonella contamination of eggs is important to improving the microbial food safety of poultry and poultry products. The hydrogen peroxide (H2O2) and ultraviolet light (UV) Advanced Oxidation Process (AOP) has been previously demonstrated to be effective in reducing Salmonella on the surface of experimentally contaminated eggs. The objective of this study was to evaluate the effect of treating eggs with an egg-sanitizing apparatus using the H2O2/UV AOP on Salmonella contamination during incubation, hatching, and in broiler chicks during grow-out. Experimentally contaminated eggs were treated using the automated H2O2/UV AOP egg sanitizer and incubated for 21 d. AOP sanitization reduced Salmonella up to 7 log10 cfu egg-1 (P Salmonella positive eggs by up to 75% (P Salmonella-positive eggs during incubation. Additionally, Salmonella was recovered from more chicks hatched from untreated eggs than from eggs treated using the H2O2/UV AOP egg sanitizer (P Salmonella contamination on the surface of eggs using the H2O2/UV AOP egg sanitizer prior to incubation may reduce the gastrointestinal colonization of chicks by Salmonella. © 2017 Poultry Science Association Inc.

Impact of litter Salmonella status during feed withdrawal on Salmonella recovery from the broiler crop and ceca.

Science.gov (United States)

Buhr, R J; Bourassa, D V; Hinton, A; Fairchild, B D; Ritz, C W

2017-12-01

Research was conducted to evaluate the impact of litter Salmonella status during feed withdrawal on Salmonella recovery from the crop and ceca following feed withdrawal. In 4 experiments, pens of broilers in separate rooms were challenged with marker strains of either Salmonella Montevideo or Salmonella Heidelberg. Three d post challenge, a 12-hour feed withdrawal was initiated, and one pen of broilers was switched between rooms for each Salmonella serotype. In experiments 3 and 4, non-challenged broilers also were added to the Salmonella challenge pens. The litter of each pen was sampled before and after the feed withdrawal period, the broilers euthanized, and the crop and ceca aseptically removed for Salmonella isolation. Results showed that only the challenge Salmonella serotype was recovered from the litter in challenge pens where broilers were not moved, while both Salmonella serotypes were recovered from the litter of the switched pens. Salmonella was recovered from 56/80 crops and from 66/80 ceca of challenged broilers that remained in the challenge pens. The challenge Salmonella serotype was recovered from 50/80 crops and from 60/80 ceca, and the switched pens' litter Salmonella serotype was recovered from 19/80 crops but not from the ceca in broilers challenged with Salmonella and then switched between pens. For experiments 3 and 4, Salmonella was recovered from 19/40 crops and from only 2/40 ceca from the non-challenged broilers placed into the Salmonella challenge pens. The results from broilers that were switched between Salmonella challenge pens indicate that the recovery of Salmonella from the crop of broilers following feed withdrawal (on Salmonella-contaminated litter) appears to depend mainly on the initial challenge Salmonella (62%) and less on the litter Salmonella (24%) status during the feed withdrawal period. In contrast, only the initial challenge Salmonella was recovered from the ceca (79%) from broilers that remained in challenge pens or

Senescent cells re-engineered to express soluble programmed death receptor-1 for inhibiting programmed death receptor-1/programmed death ligand-1 as a vaccination approach against breast cancer.

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Chen, Zehong; Hu, Kang; Feng, Lieting; Su, Ruxiong; Lai, Nan; Yang, Zike; Kang, Shijun

2018-06-01

Various types of vaccines have been proposed as approaches for prevention or delay of the onset of cancer by boosting the endogenous immune system. We previously developed a senescent-cell-based vaccine, induced by radiation and veliparib, as a preventive and therapeutic tool against triple-negative breast cancer. However, the programmed death receptor-1/programmed death ligand-1 (PD-1/PD-L1) pathway was found to play an important role in vaccine failure. Hence, we further developed soluble programmed death receptor-1 (sPD1)-expressing senescent cells to overcome PD-L1/PD-1-mediated immune suppression while vaccinating to promote dendritic cell (DC) maturity, thereby amplifying T-cell activation. In the present study, sPD1-expressing senescent cells showed a particularly active status characterized by growth arrest and modified immunostimulatory cytokine secretion in vitro. As expected, sPD1-expressing senescent tumor cell vaccine (STCV/sPD-1) treatment attracted more mature DC and fewer exhausted-PD1 + T cells in vivo. During the course of the vaccine studies, we observed greater safety and efficacy for STCV/sPD-1 than for control treatments. STCV/sPD-1 pre-injections provided complete protection from 4T1 tumor challenge in mice. Additionally, the in vivo therapeutic study of mice with s.c. 4T1 tumor showed that STCV/sPD-1 vaccination delayed tumorigenesis and suppressed tumor progression at early stages. These results showed that STCV/sPD-1 effectively induced a strong antitumor immune response against cancer and suggested that it might be a potential strategy for TNBC prevention. © 2018 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

Viral Vectors for Use in the Development of Biodefense Vaccines

Science.gov (United States)

2005-06-17

Shigella species Dengue Salmonella Filoviruses Listeria monocytogenes Ebola Campylobacter jejuni Marburg Yersinia entercolitica Viruses (Caliciviruses...Orthopoxvirus genus containing the monkey - J.S. Lee et al. / Advanced Drug Delivery Reviews 57 (2005) 1293–1314 1297 Approved for public release. Distribution...four monkeys vaccinated with V-LSGPC produced antibodies specific for LSV. After challenge, the four monkeys developed a febrile illness with low

Ensuring childhood vaccination among slums dwellers under the National Immunization Program in India - Challenges and opportunities.

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Singh, Sanjeev; Sahu, Damodar; Agrawal, Ashish; Vashi, Meeta Dhaval

2018-04-04

Almost, one third of the world's urban population resides in slums and the number would double by 2030. Slums denotes collection of people from various communities having a meagre income and living in unhygienic conditions thus making themselves most vulnerable for outbreaks of communicable diseases. India contributes substantially to the global disease burden and under-five mortality rates i.e. 20% attributable to vaccine preventable diseases. Immunization plays a crucial role in combating high childhood mortality rates attributable to vaccine preventable diseases across the globe. This systematic review, provides insights on immunization status in slums, identifies various factors influencing it thus, exploring opportunities that may be available to improve vaccination coverage under the National Immunization Program. Taking into account the above aspects, a review of literature was undertaken in various databases that included studies published between 2006 and 2017. In India, ~33% of the urban population lives in slums with suboptimal vaccination coverage ranging from 14% to upto 90%. Few of the important causes for low coverage included socioeconomic factors such as poor community participation, lack of awareness, frequent migration, and loss of daily income. Hence, mere presence of vaccines in the National Immunization Program doesn't do the job, there is a definite unmet need to emphasize upon the importance of immunization among slums dwellers and take necessary steps. For instance, delivering immunization services at the doorstep (e.g. pulse polio program), community-based education, text messaging as reminders and incentivized immunization services are some of the opportunities that can be explored and implemented to improve immunization status in the slums. Thus, in addition to inclusion of more and more vaccines in the National Immunization Program, there is a definite need to focus on people living in high risk areas in order to improve coverage and

The Asd+-DadB+ Dual-Plasmid System Offers a Novel Means To Deliver Multiple Protective Antigens by a Recombinant Attenuated Salmonella Vaccine

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Xin, Wei; Wanda, Soo-Young; Zhang, Xiangmin; Santander, Javier; Scarpellini, Giorgio; Ellis, Karen; Alamuri, Praveen

2012-01-01

We developed means to deliver multiple heterologous antigens on dual plasmids with non-antibiotic-resistance markers in a single recombinant attenuated vaccine strain of Salmonella enterica serotype Typhimurium. The first component of this delivery system is a strain of S. Typhimurium carrying genomic deletions in alr, dadB, and asd, resulting in obligate requirements for diaminopimelic acid (DAP) and d-alanine for growth. The second component is the Asd+-DadB+ plasmid pair carrying wild-type copies of asdA and dadB, respectively, to complement the mutations. To evaluate the protection efficacy of the dual-plasmid vaccine, S. Typhimurium strain χ9760 (a strain with multiple attenuating mutations: Δasd Δalr ΔdadB ΔrecF) was transformed with Asd+ and DadB+ plasmids specifying pneumococcal antigens PspA and PspC, respectively. Both plasmids were stable in χ9760 for 50 generations when grown in nonselective medium. This was significantly (P < 0.05) greater than the stability seen in its recF+ counterpart χ9590 and could be attributed to reduced interplasmid recombination in χ9760. Oral immunization of BALB/c mice with 1 × 109 CFU of χ9760 (carrying Asd+-PspA and DadB+-PspC plasmids) elicited a dominant Th1-type serum IgG response against both antigens and protected mice against intraperitoneal challenge with 200 50% lethal doses (LD50s) of virulent Streptococcus pneumoniae strain WU2 or intravenous challenge with 100 LD50s of virulent S. pneumoniae strain L81905 or intranasal challenge with a lethal dose of S. pneumoniae A66.1 in a pneumonia model. Protection offered by χ9760 was superior to that offered by the mixture of two strains, χ9828 (Asd+-PspA) and χ11026 (DadB+-PspC). This novel dual-plasmid system marks a remarkable improvement in the development of live bacterial vaccines. PMID:22868499

The Asd(+)-DadB(+) dual-plasmid system offers a novel means to deliver multiple protective antigens by a recombinant attenuated Salmonella vaccine.

Science.gov (United States)

Xin, Wei; Wanda, Soo-Young; Zhang, Xiangmin; Santander, Javier; Scarpellini, Giorgio; Ellis, Karen; Alamuri, Praveen; Curtiss, Roy

2012-10-01

We developed means to deliver multiple heterologous antigens on dual plasmids with non-antibiotic-resistance markers in a single recombinant attenuated vaccine strain of Salmonella enterica serotype Typhimurium. The first component of this delivery system is a strain of S. Typhimurium carrying genomic deletions in alr, dadB, and asd, resulting in obligate requirements for diaminopimelic acid (DAP) and d-alanine for growth. The second component is the Asd(+)-DadB(+) plasmid pair carrying wild-type copies of asdA and dadB, respectively, to complement the mutations. To evaluate the protection efficacy of the dual-plasmid vaccine, S. Typhimurium strain χ9760 (a strain with multiple attenuating mutations: Δasd Δalr ΔdadB ΔrecF) was transformed with Asd(+) and DadB(+) plasmids specifying pneumococcal antigens PspA and PspC, respectively. Both plasmids were stable in χ9760 for 50 generations when grown in nonselective medium. This was significantly (P < 0.05) greater than the stability seen in its recF(+) counterpart χ9590 and could be attributed to reduced interplasmid recombination in χ9760. Oral immunization of BALB/c mice with 1 × 10(9) CFU of χ9760 (carrying Asd(+)-PspA and DadB(+)-PspC plasmids) elicited a dominant Th1-type serum IgG response against both antigens and protected mice against intraperitoneal challenge with 200 50% lethal doses (LD(50)s) of virulent Streptococcus pneumoniae strain WU2 or intravenous challenge with 100 LD(50)s of virulent S. pneumoniae strain L81905 or intranasal challenge with a lethal dose of S. pneumoniae A66.1 in a pneumonia model. Protection offered by χ9760 was superior to that offered by the mixture of two strains, χ9828 (Asd(+)-PspA) and χ11026 (DadB(+)-PspC). This novel dual-plasmid system marks a remarkable improvement in the development of live bacterial vaccines.

Enhancing the role of veterinary vaccines reducing zoonotic diseases of humans: Linking systems biology with vaccine development

Energy Technology Data Exchange (ETDEWEB)

Adams, Leslie G.; Khare, Sangeeta; Lawhon, Sara D.; Rossetti, Carlos A.; Lewin, Harris A.; Lipton, Mary S.; Turse, Joshua E.; Wylie, Dennis C.; Bai, Yu; Drake, Kenneth L.

2011-09-22

The aim of research on infectious diseases is their prevention, and brucellosis and salmonellosis as such are classic examples of worldwide zoonoses for application of a systems biology approach for enhanced rational vaccine development. When used optimally, vaccines prevent disease manifestations, reduce transmission of disease, decrease the need for pharmaceutical intervention, and improve the health and welfare of animals, as well as indirectly protecting against zoonotic diseases of people. Advances in the last decade or so using comprehensive systems biology approaches linking genomics, proteomics, bioinformatics, and biotechnology with immunology, pathogenesis and vaccine formulation and delivery are expected to enable enhanced approaches to vaccine development. The goal of this paper is to evaluate the role of computational systems biology analysis of host:pathogen interactions (the interactome) as a tool for enhanced rational design of vaccines. Systems biology is bringing a new, more robust approach to veterinary vaccine design based upon a deeper understanding of the host pathogen interactions and its impact on the host's molecular network of the immune system. A computational systems biology method was utilized to create interactome models of the host responses to Brucella melitensis (BMEL), Mycobacterium avium paratuberculosis (MAP), Salmonella enterica Typhimurium (STM), and a Salmonella mutant (isogenic *sipA, sopABDE2) and linked to the basis for rational development of vaccines for brucellosis and salmonellosis as reviewed by Adams et al. and Ficht et al. [1,2]. A bovine ligated ileal loop biological model was established to capture the host gene expression response at multiple time points post infection. New methods based on Dynamic Bayesian Network (DBN) machine learning were employed to conduct a comparative pathogenicity analysis of 219 signaling and metabolic pathways and 1620 gene ontology (GO) categories that defined the host

Lactobacillus bulgaricus, Lactobacillus rhamnosus and Lactobacillus paracasei Attenuate Salmonella Enteritidis, Salmonella Heidelberg and Salmonella Typhimurium Colonization and Virulence Gene Expression In Vitro.

Science.gov (United States)

Muyyarikkandy, Muhammed Shafeekh; Amalaradjou, Mary Anne

2017-11-09

Salmonella Enteritidis (SE), Salmonella Typhimurium (ST), and Salmonella Heidelberg (SH) have been responsible for numerous outbreaks associated with the consumption of poultry meat and eggs. Salmonella colonization in chicken is characterized by initial attachment to the cecal epithelial cells (CEC) followed by dissemination to the liver, spleen, and oviduct. Since cecal colonization is critical to Salmonella transmission along the food chain continuum, reducing this intestinal association could potentially decrease poultry meat and egg contamination. Hence, this study investigated the efficacy of Lactobacillus delbreuckii sub species bulgaricus (NRRL B548; LD), Lactobacillus paracasei (DUP-13076; LP), and Lactobacillus rhamnosus (NRRL B442; LR) in reducing SE, ST, and SH colonization in CEC and survival in chicken macrophages. Additionally, their effect on expression of Salmonella virulence genes essential for cecal colonization and survival in macrophages was evaluated. All three probiotics significantly reduced Salmonella adhesion and invasion in CEC and survival in chicken macrophages ( p < 0.05). Further, the probiotic treatment led to a significant reduction in Salmonella virulence gene expression ( p < 0.05). Results of the study indicate that LD, LP, and LR could potentially be used to control SE, ST, and SH colonization in chicken. However, these observations warrant further in vivo validation.

Lactobacillus bulgaricus, Lactobacillus rhamnosus and Lactobacillus paracasei Attenuate Salmonella Enteritidis, Salmonella Heidelberg and Salmonella Typhimurium Colonization and Virulence Gene Expression In Vitro

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Muhammed Shafeekh Muyyarikkandy

2017-11-01

Full Text Available Salmonella Enteritidis (SE, Salmonella Typhimurium (ST, and Salmonella Heidelberg (SH have been responsible for numerous outbreaks associated with the consumption of poultry meat and eggs. Salmonella colonization in chicken is characterized by initial attachment to the cecal epithelial cells (CEC followed by dissemination to the liver, spleen, and oviduct. Since cecal colonization is critical to Salmonella transmission along the food chain continuum, reducing this intestinal association could potentially decrease poultry meat and egg contamination. Hence, this study investigated the efficacy of Lactobacillus delbreuckii sub species bulgaricus (NRRL B548; LD, Lactobacillus paracasei (DUP-13076; LP, and Lactobacillus rhamnosus (NRRL B442; LR in reducing SE, ST, and SH colonization in CEC and survival in chicken macrophages. Additionally, their effect on expression of Salmonella virulence genes essential for cecal colonization and survival in macrophages was evaluated. All three probiotics significantly reduced Salmonella adhesion and invasion in CEC and survival in chicken macrophages (p < 0.05. Further, the probiotic treatment led to a significant reduction in Salmonella virulence gene expression (p < 0.05. Results of the study indicate that LD, LP, and LR could potentially be used to control SE, ST, and SH colonization in chicken. However, these observations warrant further in vivo validation.

A randomised trial evaluating the safety and immunogenicity of the novel single oral dose typhoid vaccine M01ZH09 in healthy Vietnamese children

NARCIS (Netherlands)

Tran, Tinh Hien; Nguyen, Thi Dung; Nguyen, Thanh Truong; Ninh, Thi Thanh Van; Tran, Nguyen Bich Chau; Nguyen, Van Minh Hoang; Tran, Thi Thu Nga; Cao, Thu Thuy; Pham, Van Minh; Nguyen, Thi Cam Binh; Tran, Thi Diem Ha; Pham, Van Toi; To, Song Diep; Campbell, James I.; Stockwell, Elaine; Schultsz, Constance; Simmons, Cameron P.; Glover, Clare; Lam, Winnie; Marques, Filipe; May, James P.; Upton, Anthony; Budhram, Ronald; Dougan, Gordon; Farrar, Jeremy; Nguyen, Van Vinh Chau; Dolecek, Christiane

2010-01-01

The emergence of drug resistant typhoid fever is a major public health problem, especially in Asia. An oral single dose typhoid vaccine would have major advantages. M01ZH09 is a live oral single dose candidate typhoid vaccine containing Salmonella enterica serovar Typhi (Ty2 aroC(-)ssaV(-)) ZH9 with

Comparing human-Salmonella with plant-Salmonella protein-protein interaction predictions

Directory of Open Access Journals (Sweden)

Sylvia eSchleker

2015-01-01

Full Text Available Salmonellosis is the most frequent food-borne disease world-wide and can be transmitted to humans by a variety of routes, especially via animal and plant products. Salmonella bacteria are believed to use not only animal and human but also plant hosts despite their evolutionary distance. This raises the question if Salmonella employs similar mechanisms in infection of these diverse hosts. Given that most of our understanding comes from its interaction with human hosts, we investigate here to what degree knowledge of Salmonella-human interactions can be transferred to the Salmonella-plant system. Reviewed are recent publications on analysis and prediction of Salmonella-host interactomes. Putative protein-protein interactions (PPIs between Salmonella and its human and Arabidopsis hosts were retrieved utilizing purely interolog-based approaches in which predictions were inferred based on available sequence and domain information of known PPIs, and machine learning approaches that integrate a larger set of useful information from different sources. Transfer learning is an especially suitable machine learning technique to predict plant host targets from the knowledge of human host targets. A comparison of the prediction results with transcriptomic data shows a clear overlap between the host proteins predicted to be targeted by PPIs and their gene ontology enrichment in both host species and regulation of gene expression. In particular, the cellular processes Salmonella interferes with in plants and humans are catabolic processes. The details of how these processes are targeted, however, are quite different between the two organisms, as expected based on their evolutionary and habitat differences. Possible implications of this observation on evolution of host-pathogen communication are discussed.

Typhoid fever vaccination strategies.

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Date, Kashmira A; Bentsi-Enchill, Adwoa; Marks, Florian; Fox, Kimberley

2015-06-19

Typhoid vaccination is an important component of typhoid fever prevention and control, and is recommended for public health programmatic use in both endemic and outbreak settings. We reviewed experiences with various vaccination strategies using the currently available typhoid vaccines (injectable Vi polysaccharide vaccine [ViPS], oral Ty21a vaccine, and injectable typhoid conjugate vaccine [TCV]). We assessed the rationale, acceptability, effectiveness, impact and implementation lessons of these strategies to inform effective typhoid vaccination strategies for the future. Vaccination strategies were categorized by vaccine disease control strategy (preemptive use for endemic disease or to prevent an outbreak, and reactive use for outbreak control) and vaccine delivery strategy (community-based routine, community-based campaign and school-based). Almost all public health typhoid vaccination programs used ViPS vaccine and have been in countries of Asia, with one example in the Pacific and one experience using the Ty21a vaccine in South America. All vaccination strategies were found to be acceptable, feasible and effective in the settings evaluated; evidence of impact, where available, was strongest in endemic settings and in the short- to medium-term. Vaccination was cost-effective in high-incidence but not low-incidence settings. Experience in disaster and outbreak settings remains limited. TCVs have recently become available and none are WHO-prequalified yet; no program experience with TCVs was found in published literature. Despite the demonstrated success of several typhoid vaccination strategies, typhoid vaccines remain underused. Implementation lessons should be applied to design optimal vaccination strategies using TCVs which have several anticipated advantages, such as potential for use in infant immunization programs and longer duration of protection, over the ViPS and Ty21a vaccines for typhoid prevention and control. Copyright © 2015. Published by

Salmonella risk to consumers via pork is related to the Salmonella prevalence in pig feed.

Science.gov (United States)

Rönnqvist, M; Välttilä, V; Ranta, J; Tuominen, P

2018-05-01

Pigs are an important source of human infections with Salmonella, one of the most common causes of sporadic gastrointestinal infections and foodborne outbreaks in the European region. Feed has been estimated to be a significant source of Salmonella in piggeries in countries of a low Salmonella prevalence. To estimate Salmonella risk to consumers via the pork production chain, including feed production, a quantitative risk assessment model was constructed. The Salmonella prevalence in feeds and in animals was estimated to be generally low in Finland, but the relative importance of feed as a source of Salmonella in pigs was estimated as potentially high. Discontinuation of the present strict Salmonella control could increase the risk of Salmonella in slaughter pigs and consequent infections in consumers. The increased use of low risk and controlled feed ingredients could result in a consistently lower residual contamination in pigs and help the tracing and control of the sources of infections. Copyright © 2017 Elsevier Ltd. All rights reserved.

Impact of the introduction of the pneumococcal conjugate vaccine in the Brazilian routine childhood national immunization program.

Science.gov (United States)

Moreira, Marta; Cintra, Otavio; Harriague, Julie; Hausdorff, William P; Hoet, Bernard

2016-05-27

Brazil introduced the 10-valent pneumococcal non-typeable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV, Synflorix™, GSK Vaccines) in the routine childhood immunization program in 2010 with a 3+1 schedule (with catch-up for children media. Nasopharyngeal carriage of vaccine-type and any-type pneumococci decreased after the primary doses, with no early signs of replacement with other pathogens. Finally, herd protection against vaccine-type invasive pneumococcal disease and pneumonia in unvaccinated subjects was shown in some studies for some age groups. In conclusion, pneumococcal disease decreased after the introduction of PHiD-CV into the Brazilian national immunization program. Further follow-up is needed to evaluate the long-term overall impact of PHiD-CV in the Brazilian population. Copyright © 2016 GlaxoSmithKline Biologicals SA. Published by Elsevier Ltd.. All rights reserved.

78 FR 42526 - Salmonella

Science.gov (United States)

2013-07-16

...] Salmonella Contamination of Dry Dog Food; Withdrawal of Compliance Policy Guide AGENCY: Food and Drug... the withdrawal of the compliance policy guide (CPG) entitled ``Sec. 690.700 Salmonella Contamination... entitled ``Sec. 690.700 Salmonella Contamination of Dry Dog Food (CPG 690.700)'' on October 1, 1980. CPG...

Analysis of the evidence on the efficacy and safety of CYD-TDV dengue vaccine and its potential licensing and implementation through Mexico´s Universal Vaccination Program

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Mauricio Hernández-Ávila

2016-01-01

Full Text Available Dengue is a major global public health problem affecting Latin America and Mexico Prevention and control measures, focusing on epidemiological surveillance and vector control, have been partially effective and costly, thus, the development of a vaccine against dengue has created great expectations among health authorities and scientific communities worldwide. The CYD-TDV dengue vaccine produced by Sanofi-Pasteur is the only dengue vaccine evaluated in phase 3 controlled clinical trials. Notwithstanding the significant contribution to the development of a vaccine against dengue, the three phase 3 clinical studies of CYD-TDV and the meta-analysis of the long-term follow up of those studies, have provided evidence that this vaccine exhibited partial vaccine efficacy to protect against virologically confirmed dengue and lead to four considerations: a adequate vaccine efficacy against dengue virus (DENV infections 3 and 4, less vaccine efficacy against DENV 1 and no protection against infection by DENV 2; b decreased vaccine efficacy in dengue seronegative individuals at the beginning of the vaccination; c 83% and 90% protection against hospitalizations and severe forms of dengue, respectively, at 25 months follow-up; and d increased hospitalization for dengue in the vaccinated group, in children under nine years of age at the time of vaccination, detected since the third year of follow-up. The benefit of the CYD-TDV vaccine can be summarized in the protection against infection by DENV 3 and 4, as well as protection for hospitalizations and severe cases in people over nine years, who have had previous dengue infection, working mainly as a booster. In this review we identified elements on efficacy and safety of this vaccine that must be taken into account in the licensing process and potential inclusion in the national vaccination program of Mexico. The available scientific evidence on the CYD-TDV vaccine shows merits, but also leads to relevant

Bioinformatics analysis of Brucella vaccines and vaccine targets using VIOLIN.

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He, Yongqun; Xiang, Zuoshuang

2010-09-27

Brucella spp. are Gram-negative, facultative intracellular bacteria that cause brucellosis, one of the commonest zoonotic diseases found worldwide in humans and a variety of animal species. While several animal vaccines are available, there is no effective and safe vaccine for prevention of brucellosis in humans. VIOLIN (http://www.violinet.org) is a web-based vaccine database and analysis system that curates, stores, and analyzes published data of commercialized vaccines, and vaccines in clinical trials or in research. VIOLIN contains information for 454 vaccines or vaccine candidates for 73 pathogens. VIOLIN also contains many bioinformatics tools for vaccine data analysis, data integration, and vaccine target prediction. To demonstrate the applicability of VIOLIN for vaccine research, VIOLIN was used for bioinformatics analysis of existing Brucella vaccines and prediction of new Brucella vaccine targets. VIOLIN contains many literature mining programs (e.g., Vaxmesh) that provide in-depth analysis of Brucella vaccine literature. As a result of manual literature curation, VIOLIN contains information for 38 Brucella vaccines or vaccine candidates, 14 protective Brucella antigens, and 68 host response studies to Brucella vaccines from 97 peer-reviewed articles. These Brucella vaccines are classified in the Vaccine Ontology (VO) system and used for different ontological applications. The web-based VIOLIN vaccine target prediction program Vaxign was used to predict new Brucella vaccine targets. Vaxign identified 14 outer membrane proteins that are conserved in six virulent strains from B. abortus, B. melitensis, and B. suis that are pathogenic in humans. Of the 14 membrane proteins, two proteins (Omp2b and Omp31-1) are not present in B. ovis, a Brucella species that is not pathogenic in humans. Brucella vaccine data stored in VIOLIN were compared and analyzed using the VIOLIN query system. Bioinformatics curation and ontological representation of Brucella vaccines

Effect of the conditional cash transfer program Oportunidades on vaccination coverage in older Mexican people

Science.gov (United States)

2013-01-01

Background Immunization is one of the most effective ways of preventing illness, disability and death from infectious diseases for older people. However, worldwide immunization rates are still low, particularly for the most vulnerable groups within the elderly population. The objective of this study was to estimate the effect of the Oportunidades -an incentive-based poverty alleviation program- on vaccination coverage for poor and rural older people in Mexico. Methods Cross-sectional study, based on 2007 Oportunidades Evaluation Survey, conducted in low-income households from 741 rural communities (localities with <2,500 inhabitants) of 13 Mexican states. Vaccination coverage was defined according to three individual vaccines: tetanus, influenza and pneumococcal, and for complete vaccination schedule. Propensity score matching and linear probability model were used in order to estimate the Oportunidades effect. Results 12,146 older people were interviewed, and 7% presented cognitive impairment. Among remaining, 4,628 were matched. Low coverage rates were observed for the vaccines analyzed. For Oportunidades and non-Oportunidades populations were 46% and 41% for influenza, 52% and 45% for pneumococcal disease, and 79% and 71% for tetanus, respectively. Oportunidades effect was significant in increasing the proportion of older people vaccinated: for complete schedule 5.5% (CI95% 2.8-8.3), for influenza 6.9% (CI95% 3.8-9.6), for pneumococcal 7.2% (CI95% 4.3-10.2), and for tetanus 6.6% (CI95% 4.1-9.2). Conclusions The results of this study extend the evidence on the effect that conditional transfer programs exert on health indicators. In particular, Oportunidades increased vaccination rates in the population of older people. There is a need to continue raising vaccination rates, however, particularly for the most vulnerable older people. PMID:23835202

Salmonella biofilms

NARCIS (Netherlands)

Castelijn, G.A.A.

2013-01-01

Biofilm formation by Salmonellaspp. is a problem in the food industry, since biofilms may act as a persistent source of product contamination. Therefore the aim of this study was to obtain more insight in the processes involved and the factors contributing to Salmonellabiofilm

Genomics of Salmonella Species

Science.gov (United States)

Canals, Rocio; McClelland, Michael; Santiviago, Carlos A.; Andrews-Polymenis, Helene

Progress in the study of Salmonella survival, colonization, and virulence has increased rapidly with the advent of complete genome sequencing and higher capacity assays for transcriptomic and proteomic analysis. Although many of these techniques have yet to be used to directly assay Salmonella growth on foods, these assays are currently in use to determine Salmonella factors necessary for growth in animal models including livestock animals and in in vitro conditions that mimic many different environments. As sequencing of the Salmonella genome and microarray analysis have revolutionized genomics and transcriptomics of salmonellae over the last decade, so are new high-throughput sequencing technologies currently accelerating the pace of our studies and allowing us to approach complex problems that were not previously experimentally tractable.

Vaccine-Preventable Disease Photos

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... Work Importance of Vaccines Paying for Vaccines State Immunization Programs Tips for Finding Vaccine Records Trusted Sources of ... efficacy, and use of vaccines within the broad immunization community of patients, parents, healthcare organizations, and government health agencies.

Economic analysis for evidence-based policy-making on a national immunization program: a case of rotavirus vaccine in Thailand.

Science.gov (United States)

Muangchana, Charung; Riewpaiboon, Arthorn; Jiamsiri, Suchada; Thamapornpilas, Piyanit; Warinsatian, Porpit

2012-04-16

Severe diarrhea caused by rotavirus is a health problem worldwide, including Thailand. The World Health Organization has recommended incorporating rotavirus vaccination into national immunization programs. This policy has been implemented in several countries, but not in Thailand where the mortality rate is not high. This leads to the question of whether it would be cost-effective to implement such a policy. The Thai National Vaccine Committee, through the Immunization Practice Subcommittee, has conducted an economic analysis. Their study aimed to estimate the costs of rotavirus diarrhea and of a rotavirus vaccination program, and the cost-effectiveness of such a program including budget impact analysis. The study was designed as an economic evaluation, employing modeling technique in both provider and societal perspectives. A birth cohort of Thai children in 2009 was used in the analysis, with a 5-year time horizon. Costs were composed of cost of the illness and the vaccination program. Outcomes were measured in the form of lives saved and DALYs averted. Both costs and outcomes were discounted at 3%. The study found the discounted number of deaths to be 7.02 and 20.52 for vaccinated and unvaccinated cohorts, respectively (13.5 deaths averted). Discounted DALYs were 263.33 and 826.57 for vaccinated and unvaccinated cohorts, respectively (563.24 DALYs averted). Costs of rotavirus diarrhea in a societal perspective were US$6.6 million and US$21.0 million for vaccinated and unvaccinated cohorts, respectively. At base case, the costs per additional death averted were US$5.1 million and US$5.7 for 2-dose and 3-dose vaccines, respectively, in a societal perspective. Costs per additional DALYs averted were US$128,063 and US$142,144, respectively. In a societal perspective, with a cost-effectiveness threshold at 1 GDP per capita per DALYs averted, vaccine prices per dose were US$4.98 and US$3.32 for 2-dose and 3-dose vaccines, respectively; in a provider perspective, they

Vaccination coverage and out-of-sequence vaccinations in rural Guinea-Bissau

DEFF Research Database (Denmark)

Hornshøj, Linda; Benn, Christine Stabell; Fernandes, Manuel

2012-01-01

OBJECTIVE: The WHO aims for 90% coverage of the Expanded Program on Immunization (EPI), which in Guinea-Bissau included BCG vaccine at birth, three doses of diphtheria-tetanus-pertussis vaccine (DTP) and oral polio vaccine (OPV) at 6, 10 and 14 weeks and measles vaccine (MV) at 9 months when...

Antimicrobial drug resistance of Salmonella isolates from meat and humans, Denmark

DEFF Research Database (Denmark)

Skov, Marianne Nielsine; Andersen, Jens Strodl; Aabo, Søren

2007-01-01

We compared 8,144 Salmonella isolates collected from meat imported to or produced in Denmark, as well as from Danish patients. Isolates from imported meat showed a higher rate of antimicrobial drug resistance, including multidrug resistance, than did isolates from domestic meat. Isolates from...... humans showed resistance rates lower than those found in imported meat but higher than in domestic meat. These findings indicate that programs for controlling resistant Salmonella spp. are a global issue...

Antimicrobial drug resistance of Salmonella isolates from meat and humans, Denmark

DEFF Research Database (Denmark)

Skov, Marianne; Andersen, Jens Strodl; Aabo, Søren

2007-01-01

We compared 8,144 Salmonella isolates collected from meat imported to or produced in Denmark, as well as from Danish patients. Isolates from imported meat showed a higher rate of antimicrobial drug resistance, including multidrug resistance, than did isolates from domestic meat. Isolates from...... humans showed resistance rates lower than those found in imported meat but higher than in domestic meat. These findings indicate that programs for controlling resistant Salmonella spp. are a global issue....

Efficacy and safety of human papillomavirus vaccine for primary prevention of cervical cancer: A review of evidence from phase III trials and national programs

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Partha Basu

2013-01-01

Full Text Available The Human Papillomavirus (HPV vaccines have been widely introduced in the national immunization programs in most of the medium and high income countries following endorsement from national and international advisory bodies. HPV vaccine is unique and its introduction is challenging in many ways - it is the first vaccine developed to prevent any cancer, the vaccine is gender specific, it targets adolescent females who are difficult to reach by any health intervention programs. It is not unusual for such a vaccine to face scepticism and reservations not only from lay public but also from professionals in spite of the clinical trial results convincingly and consistently proving their efficacy and safety. Over the last few years millions of doses of the HPV vaccine have been administered round the world and the efficacy and safety data have started coming from the real life programs. A comprehensive cervical cancer control program involving HPV vaccination of the adolescent girls and screening of the adult women has been proved to be the most cost-effective approach to reduce the burden of cervical cancer. The present article discusses the justification of HPV vaccination in the backdrop of natural history of cervical cancer, the mechanism of action of the vaccines, efficacy and safety data from phase III randomized controlled trials as well as from the national immunization programs of various countries.

Estimating the Population Impact of a New Pediatric Influenza Vaccination Program in England Using Social Media Content.

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Wagner, Moritz; Lampos, Vasileios; Yom-Tov, Elad; Pebody, Richard; Cox, Ingemar J

2017-12-21

The rollout of a new childhood live attenuated influenza vaccine program was launched in England in 2013, which consisted of a national campaign for all 2 and 3 year olds and several pilot locations offering the vaccine to primary school-age children (4-11 years of age) during the influenza season. The 2014/2015 influenza season saw the national program extended to include additional pilot regions, some of which offered the vaccine to secondary school children (11-13 years of age) as well. We utilized social media content to obtain a complementary assessment of the population impact of the programs that were launched in England during the 2013/2014 and 2014/2015 flu seasons. The overall community-wide impact on transmission in pilot areas was estimated for the different age groups that were targeted for vaccination. A previously developed statistical framework was applied, which consisted of a nonlinear regression model that was trained to infer influenza-like illness (ILI) rates from Twitter posts originating in pilot (school-age vaccinated) and control (unvaccinated) areas. The control areas were then used to estimate ILI rates in pilot areas, had the intervention not taken place. These predictions were compared with their corresponding Twitter-based ILI estimates. Results suggest a reduction in ILI rates of 14% (1-25%) and 17% (2-30%) across all ages in only the primary school-age vaccine pilot areas during the 2013/2014 and 2014/2015 influenza seasons, respectively. No significant impact was observed in areas where two age cohorts of secondary school children were vaccinated. These findings corroborate independent assessments from traditional surveillance data, thereby supporting the ongoing rollout of the program to primary school-age children and providing evidence of the value of social media content as an additional syndromic surveillance tool. ©Moritz Wagner, Vasileios Lampos, Elad Yom-Tov, Richard Pebody, Ingemar J Cox. Originally published in the

Prevalence and antimicrobial resistance of Salmonella in chicken carcasses at retail in 15 Brazilian cities Prevalencia y resistencia a los antimicrobianos de Salmonella en pollos congelados de venta al por menor en 15 ciudades del Brasil

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Marcelo Augusto Nunes Medeiros

2011-12-01

Full Text Available OBJECTIVE: To describe the prevalence and antimicrobial resistance of Salmonella spp. in frozen chicken carcasses at retail from 15 Brazilian cities. METHODS: A descriptive study of data from the Brazilian National Program for Monitoring the Prevalence of Bacterial Resistance in Chicken (PREBAF was conducted from September 2004 to July 2006. The program collected chicken carcasses in 15 state capitals of Brazil in the five geographic regions of the country. Standardized methodologies were used to isolate Salmonella­spp. and identify serotypes. The minimal inhibitory concentration method was used to test resistance to 18 antimicrobials. RESULTS: In 2 679 carcasses examined, the prevalence of Salmonella spp. was 2.7% (range 0.0%-8.9%. São Paulo State produced 50.6% of positive samples. Eighteen serotypes were identified. The most frequently occurring were Salmonella Enteritidis (48.8%, Salmonella Infantis (7.6%, Salmonella Typhimurium (7.2%, and Salmonella Heidelberg (6.4%. All 250 strains tested were resistant to one or more antibiotics, and 133 (53.2% were multidrug resistant (≥ 3 classes. S. Heidelberg was resistant to ceftriaxone (75.0% and to ceftiofur(43.8%. CONCLUSIONS: The prevalence of Salmonella spp. found in this study was relatively low. However, there were a high proportion of multidrug-resistant strains, including third-generation cephalosporins used to treat invasive salmonellosis. The results confirm the relevanceof the PREBAF program. It is recommended that PREBAF be improved, including a timely data analysis. A review of permitted limits for Salmonella spp. in retail chicken in Brazil is also needed.OBJETIVO: Describir la prevalencia y la resistencia a los antibióticos de Salmonella spp. en canales de pollo congeladas de venta al por menor en 15 ciudades del Brasil. MÉTODOS: Entre septiembre del 2004 y julio del 2006 se llevó a cabo un estudio descriptivo de los datos del Programa Nacional Brasileño de Vigilancia de la

Assessment of the hepatitis B birth dose vaccination program, Papua New Guinea, 2014.

Science.gov (United States)

Wiesen, Eric; Lagani, William; Sui, Gerard; Arava, Johnnie; Reza, Salim; Diorditsa, Sergey; Lin, Yung-Ching

2016-01-12

Papua New Guinea (PNG) implemented hepatitis B birth dose (BD) vaccination in 2005 yet since that time coverage has remained low, allowing mother-to-child transmission to occur. We conducted a field assessment of the BD vaccination program to develop strategies for improving the BD coverage. We selected five provinces with higher hepatitis B prevalence and five with lower prevalence based on the results of a 2013 hepatitis B serological survey. Within each province, we interviewed district and provincial health officers, health workers, village volunteers, and caregivers from ten randomly selected health facilities. Data were collected on knowledge, practice, vaccine management and data recording/reporting. To identify enabling factors and barriers, we compared health facilities with higher BD coverage with those with lower coverage, and compared caregivers whose children received BD with those whose children did not. Overall timely BD coverage was 31% and BD vaccination was taking place in 81% of sampled health facilities. Lack of cold chain and vaccine were the major reasons for not providing the BD. Insufficiencies in supervision, vaccine management, community outreach, and data management were identified as obstacles to achieving high timely hepatitis B BD coverage. Good supervision, knowledge of hepatitis B and hepatitis B vaccination, antenatal care including information about the hepatitis B BD, provision of vaccine refrigerators in maternity wards, and outreach vaccination for home deliveries were associated with higher timely BD coverage. Several steps will likely be effective in improving BD coverage: strengthening training and supervision among health workers and officers, educating caregivers on the benefits of the BD and delivery in health facilities, improving vaccine management, and improving data quality. Considerable effort and leadership will be needed to achieve these steps. Copyright © 2015. Published by Elsevier Ltd.

Estimating the population impact of a new pediatric influenza vaccination program in England using social media content

DEFF Research Database (Denmark)

Wagner, Moritz; Lampos, Vasileios; Yom-Tov, Elad

2017-01-01

the influenza season. The 2014/2015 influenza season saw the national program extended to include additional pilot regions, some of which offered the vaccine to secondary school children (11-13 years of age) as well. Objective: We utilized social media content to obtain a complementary assessment......-age children and providing evidence of the value of social media content as an additional syndromic surveillance tool.......Background: The rollout of a new childhood live attenuated influenza vaccine program was launched in England in 2013, which consisted of a national campaign for all 2 and 3 year olds and several pilot locations offering the vaccine to primary school-age children (4-11 years of age) during...

Prevalence of Salmonella in Australian reptiles.

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Scheelings, T Franciscus; Lightfoot, Dianne; Holz, Peter

2011-01-01

From January 2007 until June 2008, 504 reptiles of four families and 57 species were examined for Salmonella by using cloacal or intestinal swabs. Salmonella was identified in 139 (28%) of the 504 animals tested. Of the 504 reptiles examined, 210 were captive and 294 were wild. Ninety-eight (47%) of the captive reptiles were shedding Salmonella at the time of sampling. In contrast, only 41 (14%) of the wild reptiles were shedding Salmonella. The higher prevalence of Salmonella in captive reptiles was statistically significant (Preptiles in Australia are not natural carriers of Salmonella and that diet and captivity may influence Salmonella excretion in other species.

lac repressor is an antivirulence factor of Salmonella enterica: its role in the evolution of virulence in Salmonella.

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Sandeepa M Eswarappa

Full Text Available The genus Salmonella includes many pathogens of great medical and veterinary importance. Bacteria belonging to this genus are very closely related to those belonging to the genus Escherichia. lacZYA operon and lacI are present in Escherichia coli, but not in Salmonella enterica. It has been proposed that Salmonella has lost lacZYA operon and lacI during evolution. In this study, we have investigated the physiological and evolutionary significance of the absence of lacI in Salmonella enterica. Using murine model of typhoid fever, we show that the expression of LacI causes a remarkable reduction in the virulence of Salmonella enterica. LacI also suppresses the ability of Salmonella enterica to proliferate inside murine macrophages. Microarray analysis revealed that LacI interferes with the expression of virulence genes of Salmonella pathogenicity island 2. This effect was confirmed by RT-PCR and Western blot analysis. Interestingly, we found that SBG0326 of Salmonella bongori is homologous to lacI of Escherichia coli. Salmonella bongori is the only other species of the genus Salmonella and it lacks the virulence genes of Salmonella pathogenicity island 2. Overall, our results demonstrate that LacI is an antivirulence factor of Salmonella enterica and suggest that absence of lacI has facilitated the acquisition of virulence genes of Salmonella pathogenicity island 2 in Salmonella enterica making it a successful systemic pathogen.

A 2011 Risk/Benefit Analysis of the Anthrax Vaccine Immunization Program

Science.gov (United States)

2011-06-10

filled with botulinum toxin, 10 with anthrax, and 2 with aflatoxin.‖18 In 1992, Ken Alibek, a senior Russian bioweapons program manager defected...William K. Honner, Rosha A. Loach , Cynthia A. Moore, and J. David Erickson. ―Birth Defects Among Infants Born to Women Who Received Anthrax Vaccine In

Costs of diarrheal disease and the cost-effectiveness of a rotavirus vaccination program in kyrgyzstan.

Science.gov (United States)

Flem, Elmira T; Latipov, Renat; Nurmatov, Zuridin S; Xue, Yiting; Kasymbekova, Kaliya T; Rheingans, Richard D

2009-11-01

We examined the cost-effectiveness of a rotavirus immunization program in Kyrgyzstan, a country eligible for vaccine funding from the GAVI Alliance. We estimated the burden of rotavirus disease and its economic consequences by using national and international data. A cost-effectiveness analysis was conducted from government and societal perspectives, along with a range of 1-way sensitivity analyses. Rotavirus-related hospitalizations and outpatient visits cost US$580,864 annually, of which $421,658 (73%) is direct medical costs and $159,206 (27%) is nonmedical and indirect costs. With 95% coverage, vaccination could prevent 75% of rotavirus-related hospitalizations and deaths and 56% of outpatient visits and could avert $386,193 (66%) in total costs annually. The medical break-even price at which averted direct medical costs equal vaccination costs is $0.65/dose; the societal break-even price is $1.14/dose for a 2-dose regimen. At the current GAVI Alliance-subsidized vaccine price of $0.60/course, rotavirus vaccination is cost-saving for the government. Vaccination is cost-effective at a vaccine price $9.41/dose, according to the cost-effectiveness standard set by the 2002 World Health Report. Addition of rotavirus vaccines to childhood immunization in Kyrgyzstan could substantially reduce disease burden and associated costs. Vaccination would be cost-effective from the national perspective at a vaccine price $9.41 per dose.

[PERSPECTIVES OF DEVELOPMENT OF LIVE RECOMBINANT ANTHRAX VACCINES BASED ON OPPORTUNISTIC AND APATHOGENIC MICROORGANISMS].

Science.gov (United States)

Popova, P Yu; Mikshis, N I

2016-01-01

Live genetic engineering anthrax vaccines on the platform of avirulent and probiotic micro-organisms are a safe and adequate alternative to preparations based on attenuated Bacillus anthracis strains. Mucosal application results in a direct contact of the vaccine preparations with mucous membranes in those organs arid tissues of the macro-organisms, that are exposed to the pathogen in the first place, resulting in a development of local and systemic immune response. Live recombinant anthrax vaccines could be used both separately as well as in a prime-boost immunization scheme. The review focuses on immunogenic and protective properties of experimental live genetic engineering prearations, created based on members of geni of Salmonella, Lactobacillus and adenoviruses.

Effect of the Infectious Bursal Disease Vaccine on the Aero-Anaerobic Enteric Bacterial Flora of Chickens

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F. A. Kembi

2001-03-01

Full Text Available The enteric bacterial flora of birds was examined after vaccination with the infectious bursal disease (IBD vaccine via the ocular and oral routes. Throughout the test period, the bacterial loads were higher in the test groups than in the control (p < 0.05. However, significant differences between the two test groups only occurred in the first three weeks postvaccination. The bacteria isolates included Salmonella sp., Edwardsiella sp., Escherichia sp. and Klebsiella sp. in the test and control groups.

[VACCINES].

Science.gov (United States)

Bellver Capella, Vincente

2015-10-01

Vaccines are an extraordinary instrument of immunization of the population against infectious diseases. Around them there are many ethical issues. One of the most debated is what to do with certain groups opposition to vaccination of their children. States have managed in different ways the conflict between the duty of vaccination and the refusal to use vaccines: some impose the vaccination and others simply promote it. In this article we deal with which of these two approaches is the most suitable from an ethical and legal point of view. We stand up for the second option, which is the current one in Spain, and we propose some measures which should be kept in mind to improve immunization programs.

Salmonella Bacteremia Among Children in Central and Northwest Nigeria, 2008–2015

Science.gov (United States)

Obaro, Stephen K.; Hassan-Hanga, Fatimah; Olateju, Eyinade K.; Umoru, Dominic; Lawson, Lovett; Olanipekun, Grace; Ibrahim, Sadeeq; Munir, Huda; Ihesiolor, Gabriel; Maduekwe, Augustine; Ohiaeri, Chinatu; Adetola, Anthony; Shetima, Denis; Jibir, Binta W.; Nakaura, Hafsat; Kocmich, Nicholas; Ajose, Therasa; Idiong, David; Masokano, Kabir; Ifabiyi, Adeyemi; Ihebuzor, Nnenna; Chen, Baojiang; Meza, Jane; Akindele, Adebayo; Rezac-Elgohary, Amy; Olaosebikan, Rasaq; Suwaid, Salman; Gambo, Mahmoud; Alter, Roxanne; Davies, Herbert D.; Fey, Paul D.

2015-01-01

Background. Etiologic agents of childhood bacteremia remain poorly defined in Nigeria. The absence of such data promotes indiscriminate use of antibiotics and delays implementation of appropriate preventive strategies. Methods. We established diagnostic laboratories for bacteremia surveillance at regional sites in central and northwest Nigeria. Acutely ill children aged <5 years with clinically suspected bacteremia were evaluated at rural and urban clinical facilities in the Federal Capital Territory, central region and in Kano, northwest Nigeria. Blood was cultured using the automated Bactec incubator system. Results. Between September 2008 and April 2015, we screened 10 133 children. Clinically significant bacteremia was detected in 609 of 4051 (15%) in the northwest and 457 of 6082 (7.5%) in the central region. Across both regions, Salmonella species account for 24%–59.8% of bacteremias and are the commonest cause of childhood bacteremia, with a predominance of Salmonella enterica serovar Typhi. The prevalence of resistance to ampicillin, chloramphenicol, and cotrimoxazole was 38.11%, with regional differences in susceptibility to different antibiotics but high prevalence of resistance to readily available oral antibiotics. Conclusions. Salmonella Typhi is the leading cause of childhood bacteremia in central Nigeria. Expanded surveillance is planned to define the dynamics of transmission. The high prevalence of multidrug-resistant strains calls for improvement in environmental sanitation in the long term and vaccination in the short term. PMID:26449948

Differential Killing of Salmonella enterica Serovar Typhi by Antibodies Targeting Vi and Lipopolysaccharide O:9 Antigen.

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Peter J Hart

Full Text Available Salmonella enterica serovar Typhi expresses a capsule of Vi polysaccharide, while most Salmonella serovars, including S. Enteritidis and S. Typhimurium, do not. Both S. Typhi and S. Enteritidis express the lipopolysaccharide O:9 antigen, yet there is little evidence of cross-protection from anti-O:9 antibodies. Vaccines based on Vi polysaccharide have efficacy against typhoid fever, indicating that antibodies against Vi confer protection. Here we investigate the role of Vi capsule and antibodies against Vi and O:9 in antibody-dependent complement- and phagocyte-mediated killing of Salmonella. Using isogenic Vi-expressing and non-Vi-expressing derivatives of S. Typhi and S. Typhimurium, we show that S. Typhi is inherently more sensitive to serum and blood than S. Typhimurium. Vi expression confers increased resistance to both complement- and phagocyte-mediated modalities of antibody-dependent killing in human blood. The Vi capsule is associated with reduced C3 and C5b-9 deposition, and decreased overall antibody binding to S. Typhi. However, purified human anti-Vi antibodies in the presence of complement are able to kill Vi-expressing Salmonella, while killing by anti-O:9 antibodies is inversely related to Vi expression. Human serum depleted of antibodies to antigens other than Vi retains the ability to kill Vi-expressing bacteria. Our findings support a protective role for Vi capsule in preventing complement and phagocyte killing of Salmonella that can be overcome by specific anti-Vi antibodies, but only to a limited extent by anti-O:9 antibodies.

Differential Killing of Salmonella enterica Serovar Typhi by Antibodies Targeting Vi and Lipopolysaccharide O:9 Antigen.

Science.gov (United States)

Hart, Peter J; O'Shaughnessy, Colette M; Siggins, Matthew K; Bobat, Saeeda; Kingsley, Robert A; Goulding, David A; Crump, John A; Reyburn, Hugh; Micoli, Francesca; Dougan, Gordon; Cunningham, Adam F; MacLennan, Calman A

2016-01-01

Salmonella enterica serovar Typhi expresses a capsule of Vi polysaccharide, while most Salmonella serovars, including S. Enteritidis and S. Typhimurium, do not. Both S. Typhi and S. Enteritidis express the lipopolysaccharide O:9 antigen, yet there is little evidence of cross-protection from anti-O:9 antibodies. Vaccines based on Vi polysaccharide have efficacy against typhoid fever, indicating that antibodies against Vi confer protection. Here we investigate the role of Vi capsule and antibodies against Vi and O:9 in antibody-dependent complement- and phagocyte-mediated killing of Salmonella. Using isogenic Vi-expressing and non-Vi-expressing derivatives of S. Typhi and S. Typhimurium, we show that S. Typhi is inherently more sensitive to serum and blood than S. Typhimurium. Vi expression confers increased resistance to both complement- and phagocyte-mediated modalities of antibody-dependent killing in human blood. The Vi capsule is associated with reduced C3 and C5b-9 deposition, and decreased overall antibody binding to S. Typhi. However, purified human anti-Vi antibodies in the presence of complement are able to kill Vi-expressing Salmonella, while killing by anti-O:9 antibodies is inversely related to Vi expression. Human serum depleted of antibodies to antigens other than Vi retains the ability to kill Vi-expressing bacteria. Our findings support a protective role for Vi capsule in preventing complement and phagocyte killing of Salmonella that can be overcome by specific anti-Vi antibodies, but only to a limited extent by anti-O:9 antibodies.

Targeted outreach hepatitis B vaccination program in high-risk adults : The fundamental challenge of the last mile

NARCIS (Netherlands)

Mangen, M. J.J.; Stibbe, H; Urbanus, A.; Siedenburg, E C; Waldhober, Q; de Wit, G. A.; Steenbergen, Eric J

2017-01-01

Background The aim of this study was to evaluate the cost-effectiveness of the on-going decentralised targeted hepatitis B vaccination program for behavioural high-risk groups operated by regional public health services in the Netherlands since 1-November-2002. Target groups for free vaccination are

Complete protection against P. berghei malaria upon heterologous prime/boost immunization against circumsporozoite protein employing Salmonella type III secretion system and Bordetella adenylate cyclase toxoid

Czech Academy of Sciences Publication Activity Database

Tartz, S.; Rüssmann, H.; Kamanová, Jana; Šebo, Peter; Sturm, A.; Heussler, V.; Fleischer, B.; Jacobs, T.

2008-01-01

Roč. 26, č. 47 (2008), s. 5935-5943 ISSN 0264-410X R&D Projects: GA MŠk 2B06161 Institutional research plan: CEZ:AV0Z50200510 Keywords : circumsporozoite protein * vaccine * salmonella Subject RIV: EE - Microbiology, Virology Impact factor: 3.298, year: 2008

An outbreak of multidrug-resistant, quinolone-resistant Salmonella enterica serotype typhimurium DT104

DEFF Research Database (Denmark)

Molbak, K.; Baggesen, Dorte Lau; Aarestrup, Frank Møller

1999-01-01

Background Food-borne salmonella infections have become a major problem in industrialized countries. The strain of Salmonella enterica serotype typhimurium known as definitive phage type 104 (DT104) is usually resistant to five drugs: ampicillin, chloramphenicol, streptomycin, sulfonamides......, and tetracycline. An increasing proportion of DT104 isolates also have reduced susceptibility to fluoroquinolones. Methods The Danish salmonella surveillance program determines the phage types of all typhimurium strains from the food chain, and in the case of suspected outbreaks, five-drug-resistant strains...... are characterized by molecular methods. All patients infected with five-drug-resistant typhimurium are interviewed to obtain clinical and epidemiologic data. In 1998, an outbreak of salmonella occurred, in which the strain of typhimurium DT104 was new to Denmark. We investigated this outbreak and report our...

Informing vaccine decision-making: A strategic multi-attribute ranking tool for vaccines-SMART Vaccines 2.0.

Science.gov (United States)

Knobler, Stacey; Bok, Karin; Gellin, Bruce

2017-01-20

SMART Vaccines 2.0 software is being developed to support decision-making among multiple stakeholders in the process of prioritizing investments to optimize the outcomes of vaccine development and deployment. Vaccines and associated vaccination programs are one of the most successful and effective public health interventions to prevent communicable diseases and vaccine researchers are continually working towards expanding targets for communicable and non-communicable diseases through preventive and therapeutic modes. A growing body of evidence on emerging vaccine technologies, trends in disease burden, costs associated with vaccine development and deployment, and benefits derived from disease prevention through vaccination and a range of other factors can inform decision-making and investment in new and improved vaccines and targeted utilization of already existing vaccines. Recognizing that an array of inputs influences these decisions, the strategic multi-attribute ranking method for vaccines (SMART Vaccines 2.0) is in development as a web-based tool-modified from a U.S. Institute of Medicine Committee effort (IOM, 2015)-to highlight data needs and create transparency to facilitate dialogue and information-sharing among decision-makers and to optimize the investment of resources leading to improved health outcomes. Current development efforts of the SMART Vaccines 2.0 framework seek to generate a weighted recommendation on vaccine development or vaccination priorities based on population, disease, economic, and vaccine-specific data in combination with individual preference and weights of user-selected attributes incorporating valuations of health, economics, demographics, public concern, scientific and business, programmatic, and political considerations. Further development of the design and utility of the tool is being carried out by the National Vaccine Program Office of the Department of Health and Human Services and the Fogarty International Center of the

Economic evaluation of the vaccination program against seasonal and pandemic A/H1N1 influenza among customs officers in Greece.

Science.gov (United States)

Mamma, Maria; Spandidos, Demetrios A

2013-01-01

Health policies from many countries recommend influenza vaccination of "high-priority" professional groups, including customs officers. Our aim was to estimate the economic impact of the vaccination program against influenza among customs officers in Greece during the 2009/2010 period. We developed a decision analytical computational simulation model including dynamic transmission elements that estimated the economic impact of various scenarios with different attack rates, symptomatic percentages and vaccination participation among customs officers. We also assessed in real-time the economic impact of the national 2009/2010 campaign against seasonal and pandemic A/H1N1 influenza. Implementing a seasonal and pandemic A/H1N1 influenza vaccination program among customs officers in Greece with a participation rate of 30%, influenza vaccination was not cost-saving in any of the studied influenza scenarios. When the participation rate reached 100%, the program was cost-saving, when the influenza attack rate was 30% and the symptomatic rate 65%. The real-time estimated mean net cost-benefit value in 2009/2010 period was -7.3 euros/custom officer. With different clinical scenarios, providing a vaccination program against seasonal and pandemic A/H1N1 influenza can incur a substantial net benefit for customs offices. However, the size of the benefit strongly depends upon the attack rate of influenza, the symptomatic rate as well as the participation rate of the customs officers in the program. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Broad-range (pan) Salmonella and Salmonella serotype typhi-specific real-time PCR assays: potential tools for the clinical microbiologist.

Science.gov (United States)

Farrell, John J; Doyle, Laura J; Addison, Rachel M; Reller, L Barth; Hall, Geraldine S; Procop, Gary W

2005-03-01

We describe broad-range salmonellae (ie, Salmonella) and Salmonella serotype Typhi-specific LightCycler (Roche Diagnostics, Indianapolis, IN) real-time polymerase chain reaction assays. We validated these with a battery of 280 bacteria, 108 of which were salmonellae representing 20 serotypes. In addition, 298 isolates from 170 clinical specimens that were suspected to possibly represent Salmonella were tested with the pan- Salmonella assay. Finally, the pan-Salmonella assay also was used to test DNA extracts from 101 archived, frozen stool specimens, 55 of which were culture-positive for salmonellae. Both assays were 100% sensitive and specific when cultured isolates of the battery were tested. The pan- Salmonella assay also characterized correctly all salmonellae on the primary isolation agar and was 96% sensitive (53/55) and 96% specific (49/51) when nucleic acid extracts from direct stool specimens were tested. These assays represent potential tools the clinical microbiologist could use to screen suspect isolates or stool specimens for Salmonella.

[The vaccination coverage rate: why is it so low?].

Science.gov (United States)

Wembonyama, O

1994-01-01

The problems hampering vaccination programs in Zaire include the inaccessibility of vaccination posts, the deplorable condition of vaccines and supplies, transport difficulties, and community disinterest. Most vaccination posts in Zaire are physically inaccessible and poorly stocked. They lack skilled staff and are unable to provide quality care. They do not have the means of providing themselves with vaccine; shortages are so common that vaccination schedules are difficult to follow. Refrigerators are usually not available in vaccination centers and are often diverted to other uses if they are available. The instructions for storing vaccines are often incorrectly followed. Single-use needles and syringes continue to be reused. Vehicles assigned to vaccination programs are often used for the private benefit of program officials or their families. Misuse of vehicles contributes to their short life expectancy. Local communities are disinterested in vaccination programs because they do not contribute to immediate survival. Moreover, the population regularly experiences the death of correctly vaccinated children. Some persons distrust vaccination as a trick to render women sterile or cause fever and convulsions in children. Mass vaccination programs are so poorly organized that their failure is predictable. The officials in charge spend most of their time in their offices rather than getting to know the target populations, and are often more interested in publicity for themselves than in the program. Press coverage is indispensable, but it should be devoted to furthering the program and not the careers of the officials in charge. Training of vaccinators, stocking of vaccination posts, and other essential tasks are often left until the last minute and improvised rather than carefully planned and implemented. The vaccinators are often unemployed persons who have little knowledge of correct techniques. Vaccination coverage could be improved if planners and health

Vaccines today, vaccines tomorrow: a perspective.

Science.gov (United States)

Loucq, Christian

2013-01-01

Vaccines are considered as one of the major contributions of the 20th century and one of the most cost effective public health interventions. The International Vaccine Institute has as a mission to discover, develop and deliver new and improved vaccines against infectious diseases that affects developing nations. If Louis Pasteur is known across the globe, vaccinologists like Maurice Hilleman, Jonas Salk and Charles Mérieux are known among experts only despite their contribution to global health. Thanks to a vaccine, smallpox has been eradicated, polio has nearly disappeared, Haemophilus influenzae B, measles and more recently meningitis A are controlled in many countries. While a malaria vaccine is undergoing phase 3, International Vaccine Institute, in collaboration with an Indian manufacturer has brought an oral inactivated cholera vaccine to pre-qualification. The field of vaccinology has undergone major changes thanks to philanthropists such as Bill and Melinda Gates, initiatives like the Decade of Vaccines and public private partnerships. Current researches on vaccines have more challenging targets like the dengue viruses, malaria, human immunodeficiency virus, the respiratory syncytial virus and nosocomial diseases. Exciting research is taking place on new adjuvants, nanoparticles, virus like particles and new route of administration. An overcrowded infant immunization program, anti-vaccine groups, immunizing a growing number of elderlies and delivering vaccines to difficult places are among challenges faced by vaccinologists and global health experts.

Diagnosis of Salmonella Enteritidis Infection in Broiler Chickens ...

African Journals Online (AJOL)

The program for the eradication of Salmonella Enteritidis from chickens was based on bacteriological examination of breeding flocks. There is a great need for a specific and sensitive serological screening test. For that purpose, four different enzyme-linked immunosorbent assays (ELISAs) were developed. These included ...

Bactericidal Immunity to Salmonella in Africans and Mechanisms Causing Its Failure in HIV Infection.

Directory of Open Access Journals (Sweden)

Yun Shan Goh

2016-04-01

Full Text Available Nontyphoidal strains of Salmonella are a leading cause of death among HIV-infected Africans. Antibody-induced complement-mediated killing protects healthy Africans against Salmonella, but increased levels of anti-lipopolysaccharide (LPS antibodies in some HIV-infected African adults block this killing. The objective was to understand how these high levels of anti-LPS antibodies interfere with the killing of Salmonella.Sera and affinity-purified antibodies from African HIV-infected adults that failed to kill invasive S. Typhimurium D23580 were compared to sera from HIV-uninfected and HIV-infected subjects with bactericidal activity. The failure of sera from certain HIV-infected subjects to kill Salmonella was found to be due to an inherent inhibitory effect of anti-LPS antibodies. This inhibition was concentration-dependent and strongly associated with IgA and IgG2 anti-LPS antibodies (p<0.0001 for both. IgG anti-LPS antibodies, from sera of HIV-infected individuals that inhibit killing at high concentration, induced killing when diluted. Conversely, IgG, from sera of HIV-uninfected adults that induce killing, inhibited killing when concentrated. IgM anti-LPS antibodies from all subjects also induced Salmonella killing. Finally, the inhibitory effect of high concentrations of anti-LPS antibodies is seen with IgM as well as IgG and IgA. No correlation was found between affinity or avidity, or complement deposition or consumption, and inhibition of killing.IgG and IgM classes of anti-S. Typhimurium LPS antibodies from HIV-infected and HIV-uninfected individuals are bactericidal, while at very high concentrations, anti-LPS antibodies of all classes inhibit in vitro killing of Salmonella. This could be due to a variety of mechanisms relating to the poor ability of IgA and IgG2 to activate complement, and deposition of complement at sites where it cannot insert in the bacterial membrane. Vaccine trials are required to understand the significance of

Schools as potential vaccination venue for vaccines outside regular EPI schedule: results from a school census in Pakistan.

Science.gov (United States)

Soofi, Sajid Bashir; Haq, Inam-Ul; Khan, M Imran; Siddiqui, Muhammad Bilal; Mirani, Mushtaq; Tahir, Rehman; Hussain, Imtiaz; Puri, Mahesh K; Suhag, Zamir Hussain; Khowaja, Asif R; Lasi, Abdul Razzaq; Clemens, John D; Favorov, Michael; Ochiai, R Leon; Bhutta, Zulfiqar A

2012-01-06

Vaccines are the most effective public health intervention. Expanded Program on Immunization (EPI) provides routine vaccination in developing countries. However, vaccines that cannot be given in EPI schedule such as typhoid fever vaccine need alternative venues. In areas where school enrolment is high, schools provide a cost effective opportunity for vaccination. Prior to start of a school-based typhoid vaccination program, interviews were conducted with staff of educational institutions in two townships of Karachi, Pakistan to collect baseline information about the school system and to plan a typhoid vaccination program. Data collection teams administered a structured questionnaire to all schools in the two townships. The administrative staff was requested information on school fee, class enrolment, past history of involvement and willingness of parents to participate in a vaccination campaign. A total of 304,836 students were enrolled in 1,096 public, private, and religious schools (Madrasahs) of the two towns. Five percent of schools refused to participate in the school census. Twenty-five percent of schools had a total enrolment of less than 100 students whereas 3% had more than 1,000 students. Health education programs were available in less than 8% of public schools, 17% of private schools, and 14% of Madrasahs. One-quarter of public schools, 41% of private schools, and 43% of Madrasahs had previously participated in a school-based vaccination campaign. The most common vaccination campaign in which schools participated was Polio eradication program. Cost of the vaccine, side effects, and parents' lack of information were highlighted as important limiting factors by school administration for school-based immunization programs. Permission from parents, appropriateness of vaccine-related information, and involvement of teachers were considered as important factors to improve participation. Health education programs are not part of the regular school curriculum

Schools as potential vaccination venue for vaccines outside regular EPI schedule: results from a school census in Pakistan

Directory of Open Access Journals (Sweden)

Soofi Sajid

2012-01-01

Full Text Available Abstract Background Vaccines are the most effective public health intervention. Expanded Program on Immunization (EPI provides routine vaccination in developing countries. However, vaccines that cannot be given in EPI schedule such as typhoid fever vaccine need alternative venues. In areas where school enrolment is high, schools provide a cost effective opportunity for vaccination. Prior to start of a school-based typhoid vaccination program, interviews were conducted with staff of educational institutions in two townships of Karachi, Pakistan to collect baseline information about the school system and to plan a typhoid vaccination program. Data collection teams administered a structured questionnaire to all schools in the two townships. The administrative staff was requested information on school fee, class enrolment, past history of involvement and willingness of parents to participate in a vaccination campaign. Results A total of 304,836 students were enrolled in 1,096 public, private, and religious schools (Madrasahs of the two towns. Five percent of schools refused to participate in the school census. Twenty-five percent of schools had a total enrolment of less than 100 students whereas 3% had more than 1,000 students. Health education programs were available in less than 8% of public schools, 17% of private schools, and 14% of Madrasahs. One-quarter of public schools, 41% of private schools, and 43% of Madrasahs had previously participated in a school-based vaccination campaign. The most common vaccination campaign in which schools participated was Polio eradication program. Cost of the vaccine, side effects, and parents' lack of information were highlighted as important limiting factors by school administration for school-based immunization programs. Permission from parents, appropriateness of vaccine-related information, and involvement of teachers were considered as important factors to improve participation. Conclusions Health

Dynamic modeling of cost-effectiveness of rotavirus vaccination, Kazakhstan.

Science.gov (United States)

Freiesleben de Blasio, Birgitte; Flem, Elmira; Latipov, Renat; Kuatbaeva, Ajnagul; Kristiansen, Ivar Sønbø

2014-01-01

The government of Kazakhstan, a middle-income country in Central Asia, is considering the introduction of rotavirus vaccination into its national immunization program. We performed a cost-effectiveness analysis of rotavirus vaccination spanning 20 years by using a synthesis of dynamic transmission models accounting for herd protection. We found that a vaccination program with 90% coverage would prevent ≈880 rotavirus deaths and save an average of 54,784 life-years for children vaccine cost at vaccination program costs would be entirely offset. To further evaluate efficacy of a vaccine program, benefits of indirect protection conferred by vaccination warrant further study.

A comparative analysis of influenza vaccination programs.

Directory of Open Access Journals (Sweden)

Shweta Bansal

2006-10-01

Full Text Available BACKGROUND: The threat of avian influenza and the 2004-2005 influenza vaccine supply shortage in the United States have sparked a debate about optimal vaccination strategies to reduce the burden of morbidity and mortality caused by the influenza virus. METHODS AND FINDINGS: We present a comparative analysis of two classes of suggested vaccination strategies: mortality-based strategies that target high-risk populations and morbidity-based strategies that target high-prevalence populations. Applying the methods of contact network epidemiology to a model of disease transmission in a large urban population, we assume that vaccine supplies are limited and then evaluate the efficacy of these strategies across a wide range of viral transmission rates and for two different age-specific mortality distributions. We find that the optimal strategy depends critically on the viral transmission level (reproductive rate of the virus: morbidity-based strategies outperform mortality-based strategies for moderately transmissible strains, while the reverse is true for highly transmissible strains. These results hold for a range of mortality rates reported for prior influenza epidemics and pandemics. Furthermore, we show that vaccination delays and multiple introductions of disease into the community have a more detrimental impact on morbidity-based strategies than mortality-based strategies. CONCLUSIONS: If public health officials have reasonable estimates of the viral transmission rate and the frequency of new introductions into the community prior to an outbreak, then these methods can guide the design of optimal vaccination priorities. When such information is unreliable or not available, as is often the case, this study recommends mortality-based vaccination priorities.

Microbiologic and Clinical Features of Salmonella Species Isolated From Bacteremic Children in Eastern Democratic Republic of Congo

DEFF Research Database (Denmark)

Vandenberg, Olivier; Nyarukweba, Deo Z.; Ndeba, Prudence M.

2010-01-01

Background: The morbidity of Salmonella bloodstream infections is unacceptably high in Africa. In 2000, the WHO Global Salmonella-Surveillance (GSS) program was founded to reduce the health burden of foodborne diseases. The incorporation, in 2002, of the Democratic Republic of Congo (DRC......) in this program allowed the improvement of laboratory capacities. In this retrospective study, we describe the first signs of impact the GSS program has had in DRC in the management of bacteremia. Methods: Between 2002 and 2006, we evaluated, in one pediatric hospital, the microbiologic and clinical features...

Vaccination program in a resource-limited setting: A case study in the Philippines.

Science.gov (United States)

Chootipongchaivat, Sarocha; Chantarastapornchit, Varit; Kulpeng, Wantanee; Ceria, Joyce Anne; Tolentino, Niña Isabelle; Teerawattananon, Yot

2016-09-14

Implementing national-level vaccination programs involves long-term investment, which can be a significant financial burden, particularly in resource-limited settings. Although many studies have assessed the economic impacts of providing vaccinations, evidence on the positive and negative implications of human resources for health (HRH) is still lacking. Therefore, this study aims to estimate the HRH impact of introducing pneumococcal conjugate vaccine (PCV) using a model-based economic evaluation. This study adapted a Markov model from a prior study that was conducted in the Philippines for assessing the cost-effectiveness of 10-valent and 13-valent PCV compared to no vaccination. The Markov model was used for estimating the number of cases of pneumococcal-related diseases, categorized by policy options. HRH-related parameters were obtained from document reviews and interviews using the quantity, task, and productivity model (QTP model). The number of full-time equivalent (FTE) of general practitioners, nurses, and midwives increases significantly if the universal vaccine coverage policy is implemented. A universal coverage of PCV13 - which is considered to be the best value for money compared to other vaccination strategies - requires an additional 380 FTEs for general practitioners, 602 FTEs for nurses, and 205 FTEs for midwives; it can reduce the number of FTEs for medical social workers, paediatricians, infectious disease specialists, neurologists, anaesthesiologists, radiologists, ultrasonologists, medical technologists, radiologic technologists, and pharmacists by 7, 17.9, 9.7, 0.4, 0.1, 0.7, 0.1, 12.3, 2, and 9.7, respectively, when compared to the no vaccination policy. This is the first attempt to estimate the impact of HRH alongside a model-based economic evaluation study, which can be eventually applied to other vaccine studies, especially those which inform resource allocation in developing settings where not only financial resources but also HRH are

Next generation vaccines.

Science.gov (United States)

Riedmann, Eva M

2011-07-01

In February this year, about 100 delegates gathered for three days in Vienna (Austria) for the Next Generation Vaccines conference. The meeting held in the Vienna Hilton Hotel from 23rd-25th February 2011 had a strong focus on biotech and industry. The conference organizer Jacob Fleming managed to put together a versatile program ranging from the future generation of vaccines to manufacturing, vaccine distribution and delivery, to regulatory and public health issues. Carefully selected top industry experts presented first-hand experience and shared solutions for overcoming the latest challenges in the field of vaccinology. The program also included several case study presentations on novel vaccine candidates in different stages of development. An interactive pre-conference workshop as well as interactive panel discussions during the meeting allowed all delegates to gain new knowledge and become involved in lively discussions on timely, interesting and sometimes controversial topics related to vaccines.

Changes in the epidemiology of hepatitis A outbreaks 13 years after the introduction of a mass vaccination program

Science.gov (United States)

Martínez, Ana; Broner, Sonia; Sala, M Rosa; Manzanares-Laya, Sandra; Godoy, Pere; Planas, Caritat; Minguell, Sofia; Torner, Nuria; Jané, Mireia; Domínguez, Angela; for the Study of the Immune Status in Health Care, the Working Group; Hepatitis A in Catalonia, for the Study of

2014-01-01

A hepatitis A+B vaccine vaccination program of 12-year-olds was introduced in Catalonia in 1998. The aim of this study was to investigate the evolution of hepatitis A outbreaks in Catalonia and estimate the preventable fraction of cases associated with outbreaks as a measure of the impact of the vaccination program. Hepatitis A outbreaks reported to the Health Department between 1991 and 2012 were analyzed. The incidence rates of outbreaks, outbreak-associated cases and hospitalizations were calculated. The preventable fraction (PF) and 95% confidence intervals (CI) were estimated for the whole study period (pre-vaccination and post-vaccination) and the post-vaccination period. One-hundred-eight (108) outbreaks (rate of 2.21 per 106 persons-year) were reported in the pre-vaccination period and 258 outbreaks (rate of 2.82 per 106 persons-year) in the post-vaccination period. The rate of cases associated with outbreaks was 1.52 per 105 persons-year in the pre-vaccination period and 1.28 per 105 persons-year in the post-vaccination period. Hospitalization rates were 0.08 and 0.75 per 106 persons-year, respectively. The number of person-to-person outbreaks whose index case was a school contact decreased in the post-vaccination period (aOR 2.72; 95%CI 1.35–5.48), but outbreaks whose index case was a man who has sex with men (MSM) or an immigrant increased. The PF of all outbreak-associated cases was 6.46% (95%CI 3.11–9.82) and the highest PF was in the 15–24 years age group (42.53%; 95%CI 29.30–55.75). In the 0–4 years age group, the PF was 18.35% (95%CI 9.59–27.11), suggesting a protective herd effect in unvaccinated subjects. Vaccination of immigrants traveling to endemic countries and MSM should be reinforced. PMID:25483535

Current status of rotavirus vaccines.

Science.gov (United States)

Wang, Ching-Min; Chen, Shou-Chien; Chen, Kow-Tong

2015-11-01

Rotaviruses remain the major cause of childhood diarrheal disease worldwide and of diarrheal deaths of infants and children in developing countries. The huge burden of childhood rotavirus-related diarrhea in the world continues to drive the remarkable pace of vaccine development. Research articles were searched using terms "rotavirus" and "rotavirus vaccine" in MEDLINE and PubMed. Articles not published in the English language, articles without abstracts, and opinion articles were excluded from the review. After preliminary screening, all articles were reviewed and synthesized to provide an overview of current vaccines and vaccination programs. In this review of the global rotavirus vaccines and vaccination programs, the principles of rotavirus vaccine development and the efficacy of the currently licensed vaccines from both developed and developing countries were summarized. Rotavirus is a common cause of diarrhea in children in both developed and developing countries. Rotavirus vaccination is a cost-effective measure to prevent rotavirus diarrhea.

76 FR 36367 - National Vaccine Injury Compensation Program: Revisions to the Vaccine Injury Table

Science.gov (United States)

2011-06-22

... hepatitis A, trivalent influenza, meningococcal, and human papillomavirus vaccines. The Secretary is now... within the time period prescribed. IV. Vaccines containing A. Chronic arthritis.. 7-42 days. rubella... days. virus (e.g., MMR, MR, M). purpura. B. Vaccine-Strain 6 months. Measles Viral Infection in an...

Recent Trends in Salmonella Outbreaks and Emerging Technology for Biocontrol of Salmonella Using Phages in Foods: A Review.

Science.gov (United States)

Oh, Jun-Hyun; Park, Mi-Kyung

2017-12-28

Salmonella is one of the principal causes of foodborne outbreaks. As traditional control methods have shown less efficacy against emerging Salmonella serotypes or antimicrobialresistant Salmonella , new approaches have been attempted. The use of lytic phages for the biocontrol of Salmonella in the food industry has become an attractive method owing to the many advantages offered by the use of phages as biocontrol agents. Phages are natural alternatives to traditional antimicrobial agents; they have proven effective in the control of bacterial pathogens in the food industry, which has led to the development of different phage products. The treatment with specific phages in the food industry can prevent the decay of products and the spread of bacterial diseases, and ultimately promotes safe environments for animal and plant food production, processing, and handling. After an extensive investigation of the current literature, this review focuses predominantly on the efficacy of phages for the successful control of Salmonella spp. in foods. This review also addresses the current knowledge on the pathogenic characteristics of Salmonella , the prevalence of emerging Salmonella outbreaks, the isolation and characterization of Salmonella -specific phages, the effectiveness of Salmonella -specific phages as biocontrol agents, and the prospective use of Salmonella -specific phages in the food industry.

To vaccinate or not to vaccinate? Perspectives on HPV vaccination among girls, boys, and parents in the Netherlands: A Q-methodological study

NARCIS (Netherlands)

Patty, N.J.S. (Nathalie J. S.); H.M. van Dijk (Hanna); I. Wallenburg (Iris); R.A. Bal (Roland); T.J.M. Helmerhorst (Theo); Van Exel, J. (Job); J.M. Cramm (Jane)

2017-01-01

textabstractBackground: Despite the introduction of Human papillomavirus (HPV) vaccination in national immunization programs (NIPs), vaccination rates in most countries remain relatively low. An understanding of the reasons underlying decisions about whether to vaccinate is essential in order to

Antiangiogenic immunotherapy targeting Flk-1, DNA vaccine and adoptive T cell transfer, inhibits ocular neovascularization

Energy Technology Data Exchange (ETDEWEB)

Zhang, Han [Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-Ku, Fukuoka 812-8582 (Japan); Sonoda, Koh-Hei, E-mail: sonodak@med.kyushu-u.ac.jp [Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-Ku, Fukuoka 812-8582 (Japan); Hijioka, Kuniaki; Qiao, Hong; Oshima, Yuji; Ishibashi, Tatsuro [Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-Ku, Fukuoka 812-8582 (Japan)

2009-04-17

Ocular neovascularization (NV) is the primary cause of blindness in a wide range of ocular diseases. The exact mechanism underlying the pathogenesis of ocular NV is not yet well understood, and so there is no satisfactory therapy for ocular NV. Here, we describe a strategy targeting Flk-1, a self-antigen overexpressed on proliferating endothelial cells in ocular NV, by antiangiogenic immunotherapy-DNA vaccine and adoptive T cell therapy. An oral DNA vaccine encoding Flk-1 carried by attenuated Salmonella typhimurium markedly suppressed development of laser-induced choroidal NV. We further demonstrated that adoptive transfer of vaccine-induced CD8{sup +} T cells reduced pathological preretinal NV, with a concomitant facilitation of physiological revascularization after oxygen-induced retinal vessel obliteration. However, physiological retinal vascular development was unaffected in neonatal mice transferred with vaccine-induced CD8{sup +} T cells. These findings suggested that antiangiogenic immunotherapy targeting Flk-1 such as vaccination and adoptive immunotherapy may contribute to future therapies for ocular NV.

Antiangiogenic immunotherapy targeting Flk-1, DNA vaccine and adoptive T cell transfer, inhibits ocular neovascularization

International Nuclear Information System (INIS)

Zhang, Han; Sonoda, Koh-Hei; Hijioka, Kuniaki; Qiao, Hong; Oshima, Yuji; Ishibashi, Tatsuro

2009-01-01

Ocular neovascularization (NV) is the primary cause of blindness in a wide range of ocular diseases. The exact mechanism underlying the pathogenesis of ocular NV is not yet well understood, and so there is no satisfactory therapy for ocular NV. Here, we describe a strategy targeting Flk-1, a self-antigen overexpressed on proliferating endothelial cells in ocular NV, by antiangiogenic immunotherapy-DNA vaccine and adoptive T cell therapy. An oral DNA vaccine encoding Flk-1 carried by attenuated Salmonella typhimurium markedly suppressed development of laser-induced choroidal NV. We further demonstrated that adoptive transfer of vaccine-induced CD8 + T cells reduced pathological preretinal NV, with a concomitant facilitation of physiological revascularization after oxygen-induced retinal vessel obliteration. However, physiological retinal vascular development was unaffected in neonatal mice transferred with vaccine-induced CD8 + T cells. These findings suggested that antiangiogenic immunotherapy targeting Flk-1 such as vaccination and adoptive immunotherapy may contribute to future therapies for ocular NV.

25 years after Vi typhoid vaccine efficacy study, typhoid affects significant number of population in Nepal.

Directory of Open Access Journals (Sweden)

Deepak Bajracharya

Full Text Available Salmonella Typhi, first isolated in 1884, results in infection of the intestines and can end in death and disability. Due to serious adverse events post vaccination, whole cell killed vaccines have been replaced with new generation vaccines. The efficacy of Vi polysaccharide (ViPS vaccine, a new generation, single-dose intramuscular typhoid vaccine was assessed in Nepal in 1987. However, despite the availability of ViPS vaccine for more than 25 years, Nepal has one of the highest incidence of typhoid fever. Therefore we collected information from hospitals in the Kathmandu Valley from over the past five years. There were 9901 enteric fever cases between January 2008 and July 2012. 1,881 of these were confirmed typhoid cases from five hospitals in the Kathmandu district. Approximately 70% of the cases involved children under 15 years old. 1281 cases were confirmed as S. Paratyphi. Vaccines should be prioritized for control of typhoid in conjunction with improved water and sanitation conditions in Nepal and in endemic countries of Asia and Africa.

Isolation and Evaluation Virulence Factors of Salmonella typhimurium and Salmonella enteritidis in Milk and Dairy Products

Directory of Open Access Journals (Sweden)

Shima Shaigan nia

2014-06-01

Conclusions: To our best knowledge the present study is the first prevalence report of Salmonella spp., Salmonella enteritidis and Salmonella typhimurium in raw sheep and goat samples in Iran. Consumption of pasteurized milk and dairy products can reduce the risk of salmonellosis.

Life course vaccination and healthy aging.

Science.gov (United States)

Gusmano, Michael K; Michel, Jean-Pierre

2009-06-01

The authors notice the low vaccine coverage rate among European citizens and inventory the multiple reasons leading to the non-use of preventable infectious diseases vaccines in adults whose mortality consequences represent an important and unexpected burden of diseases. These facts are in close relation with the disruption of vaccine recommendations after the childhood vaccine program, the poor literacy knowledge concerning vaccines among the general population, but also unfortunately among physicians and other health care workers. Popular beliefs, fear of side-effects, fear of needles facilitated the constitution of active non-vaccine groups which conduct to the reappearance in non-vaccinated adults and with dramatic consequences of preventable childhood infectious diseases. This careful analysis of the current preventable infectious disease vaccine coverage in old adults leads to propose a life course vaccine programme including adult vaccinations as part of healthy aging as well as old adults' vaccine guidelines integrated in health prevention programs.

How influenza vaccination policy may affect vaccine logistics.

Science.gov (United States)

Assi, Tina-Marie; Rookkapan, Korngamon; Rajgopal, Jayant; Sornsrivichai, Vorasith; Brown, Shawn T; Welling, Joel S; Norman, Bryan A; Connor, Diana L; Chen, Sheng-I; Slayton, Rachel B; Laosiritaworn, Yongjua; Wateska, Angela R; Wisniewski, Stephen R; Lee, Bruce Y

2012-06-22

When policymakers make decision about the target populations and timing of influenza vaccination, they may not consider the impact on the vaccine supply chains, which may in turn affect vaccine availability. Our goal is to explore the effects on the Thailand vaccine supply chain of introducing influenza vaccines and varying the target populations and immunization time-frames. We Utilized our custom-designed software HERMES (Highly Extensible Resource for Modeling Supply Chains), we developed a detailed, computational discrete-event simulation model of the Thailand's National Immunization Program (NIP) supply chain in Trang Province, Thailand. A suite of experiments simulated introducing influenza vaccines for different target populations and over different time-frames prior to and during the annual influenza season. Introducing influenza vaccines creates bottlenecks that reduce the availability of both influenza vaccines as well as the other NIP vaccines, with provincial to district transport capacity being the primary constraint. Even covering only 25% of the Advisory Committee on Immunization Practice-recommended population while administering the vaccine over six months hinders overall vaccine availability so that only 62% of arriving patients can receive vaccines. Increasing the target population from 25% to 100% progressively worsens these bottlenecks, while increasing influenza vaccination time-frame from 1 to 6 months decreases these bottlenecks. Since the choice of target populations for influenza vaccination and the time-frame to deliver this vaccine can substantially affect the flow of all vaccines, policy-makers may want to consider supply chain effects when choosing target populations for a vaccine. Copyright © 2012 Elsevier Ltd. All rights reserved.

PREVALENCE OF SALMONELLA IN CAPTIVE REPTILES FROM CROATIA.

Science.gov (United States)

Lukac, Maja; Pedersen, Karl; Prukner-Radovcic, Estella

2015-06-01

Salmonellosis transmitted by pet reptiles is an increasing public health issue worldwide. The aim of this study was to investigate the prevalence of Salmonella strains from captive reptiles in Croatia. From November 2009 to November 2011 a total of 292 skin, pharyngeal, cloacal, and fecal samples from 200 apparently healthy reptiles were tested for Salmonella excretions by bacteriologic culture and serotyping. These 200 individual reptiles included 31 lizards, 79 chelonians, and 90 snakes belonging to private owners or housed at the Zagreb Zoo, Croatia. Salmonella was detected in a total of 13% of the animals, among them 48.4% lizards, 8.9% snakes, and 3.8% turtles. Representatives of five of the six Salmonella enterica subspecies were identified with the following proportions in the total number of isolates: Salmonella enterica enterica 34.6%, Salmonella enterica houtenae 23.1%, Salmonella enterica arizonae 23.1%, Salmonella enterica diarizonae 15.4%, and Salmonella enterica salamae 3.8%. The 14 different serovars isolated included several rarely occurring serovars such as Salmonella Apapa, Salmonella Halle, Salmonella Kisarawe, and Salmonella Potengi. These findings confirm that the prevalence of Salmonella is considerable in captive reptiles in Croatia, indicating that these animals may harbor serovars not commonly seen in veterinary or human microbiologic practice. This should be addressed in the prevention and diagnostics of human reptile-transmitted infections.

Effectiveness of a vaccination program against mumps in Ukraine.

Science.gov (United States)

Hrynash, Y; Nadraga, A; Dasho, M

2008-12-01

Medical records and incidence data were analyzed retrospectively to document the epidemiology, clinical features, and outcomes of mumps in relation to vaccination status in the Lviv province of Ukraine over a 7.5-year period, beginning in 2000, when a second dose of mumps vaccine was introduced. Lviv, 1 of 27 provinces in western Ukraine, with a land area of 21,833 km(2), had a total population of about 2,555,834 in 2006. The initial success of the second dose introduction in 2000 in Ukraine was limited by a local outbreak of mumps in Lviv province in 2000-2002 due to a vaccine shortage; most cases were over the age of 7 years. The vaccine with the Leningrad-3 virus strain used before 2001 was then replaced by the triple vaccine "Priorix", with the RIT 4385 derivate of the Jeryl Lynn strain, Belgium. Orchitis and aseptic meningitis were associated with the Russian vaccine. Of the 10,894 reported cases, the most severe (367 cases, 3.4%) were hospitalized in the Lviv Hospital for Infectious Diseases. Admitted patients were predominantly male and over 14 years old. Of the 367 patients admitted to the Lviv Hospital for Infectious Diseases, 45.8% had been vaccinated (mostly by a first dose of Russian vaccine), 15.9% had not been vaccinated, and 38.1% had an unknown vaccination status. More mumps cases occurred in winter and spring than in summer and autumn. The clinical picture and complications (orchitis, pancreatitis, meningitis, and encephalitis) were typical of this disease. The vaccine shortage and an increase in the susceptible population among those who received the Russian vaccine contributed to the outbreak. The use of vaccine with a derivate of the Jeryl Lynn strain has resulted in a dramatic drop in mumps cases since 2002.

Vaccine Hesitancy Among Caregivers and Association with Childhood Vaccination Timeliness in Addis Ababa, Ethiopia.

Science.gov (United States)

Masters, Nina B; Tefera, Yemesrach A; Wagner, Abram L; Boulton, Matthew L

2018-05-24

Vaccines are vital to reducing childhood mortality, and prevent an estimated 2 to 3 million deaths annually which disproportionately occur in the developing world. Overall vaccine coverage is typically used as a metric to evaluate the adequacy of vaccine program performance, though it does not account for untimely administration, which may unnecessarily prolong children's susceptibility to disease. This study explored a hypothesized positive association between increasing vaccine hesitancy and untimeliness of immunizations administered under the Expanded Program on Immunization (EPI) in Addis Ababa, Ethiopia. This cross-sectional survey employed a multistage sampling design, randomly selecting one health center within five sub-cities of Addis Ababa. Caregivers of 3 to 12-month-old infants completed a questionnaire on vaccine hesitancy, and their infants' vaccination cards were examined to assess timeliness of received vaccinations. The sample comprised 350 caregivers. Overall, 82.3% of the surveyed children received all recommended vaccines, although only 55.9% of these vaccinations were timely. Few caregivers (3.4%) reported ever hesitating and 3.7% reported ever refusing a vaccine for their child. Vaccine hesitancy significantly increased the odds of untimely vaccination (AOR 1.94, 95% CI: 1.02, 3.71) in the adjusted analysis. This study found high vaccine coverage among a sample of 350 young children in Addis Ababa, though only half received all recommended vaccines on time. High vaccine hesitancy was strongly associated with infants' untimely vaccination, indicating that increased efforts to educate community members and providers about vaccines may have a beneficial impact on vaccine timeliness in Addis Ababa.

The Impact of School-Located Influenza Vaccination Programs on Student Absenteeism: A Review of the U.S. Literature

Science.gov (United States)

Hull, Harry F.; Ambrose, Christopher S.

2011-01-01

A literature review was conducted to summarize the impact of school-located influenza vaccination (SLIV) programs on school absenteeism. Seven studies were identified: six peer-reviewed articles and one conference presentation. The number of students vaccinated ranged from 185 to 5,315, representing 35-86% of enrolled students. Six studies…

Vaccine Safety Datalink

Science.gov (United States)

The Vaccine Safety Datalink is part of the National Immunization Program within the Centers for Disease Control and Prevention and was started in recognition of gaps in the scientific knowledge of rare vaccine side effects.

Parental Preferences for the Organization of Preschool Vaccination Programs Including Financial Incentives: A Discrete Choice Experiment

Directory of Open Access Journals (Sweden)

Darren Flynn PhD

2017-05-01

Full Text Available Objective: To establish preferences of parents and guardians of preschool children for the organization of preschool vaccination services, including financial incentives. Design: An online discrete choice experiment. Participants: Parents and guardians of preschool children (up to age 5 years who were (n = 259 and were not (n = 262 classified as at high risk of incompletely vaccinating their children. High risk of incomplete vaccination was defined as any of the following: aged less than 20 years, single parents, living in one of the 20% most deprived areas in England, had a preschool child with a disability, or had more than three children. Main Outcome Measures: Participant preferences expressed as positive (utility or negative (disutility on eight attributes and levels describing the organization of preschool vaccination programs. Results: There was no difference in preference for parental financial incentives compared to no incentive in parents “not at high risk” of incomplete vaccination. Parents who were “at high risk” expressed utility for cash incentives. Parents “at high risk” of incomplete vaccination expressed utility for information on the risks and benefits of vaccinations to be provided as numbers rather than charts or pictures. Both groups preferred universally available, rather than targeted, incentives. Utility was identified for shorter waiting times, and there were variable preferences for who delivered vaccinations. Conclusions: Cash incentives for preschool vaccinations in England would be welcomed by parents who are “at high risk” of incompletely vaccinating their children. Further work is required on the optimal mode and form of presenting probabilistic information on vaccination to parents/guardians, including preferences on mandatory vaccination schemes.

9 CFR 113.122 - Salmonella Choleraesuis Bacterin.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Salmonella Choleraesuis Bacterin. 113... REQUIREMENTS Inactivated Bacterial Products § 113.122 Salmonella Choleraesuis Bacterin. Salmonella Choleraesuis Bacterin shall be prepared from a culture of Salmonella choleraesuis which has been inactivated and is...

9 CFR 113.120 - Salmonella Typhimurium Bacterin.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Salmonella Typhimurium Bacterin. 113... REQUIREMENTS Inactivated Bacterial Products § 113.120 Salmonella Typhimurium Bacterin. Salmonella Typhimurium Bacterin shall be prepared from a culture of Salmonella typhimurium which has been inactivated and is...

Salmonella spp. in raw broiler parts: occurrence, antimicrobial resistance profile and phage typing of the Salmonella Enteritidis isolates Salmonella spp. em cortes de frango: ocorrência, resistência antimicrobiana e fagotipificação dos isolados de Salmonella Enteritidis

Directory of Open Access Journals (Sweden)

Aldemir Reginato Ribeiro

2007-06-01

Full Text Available The present study was carried out to evaluate the occurrence of Salmonellae in raw broiler parts and to determine the antimicrobial resistance profile of the isolated strains. Twenty-four (39.3% broiler parts samples were positive for Salmonella and twenty-five Salmonella strains were isolated, since two different serovars were detected in one single positive sample. Salmonella Enteritidis was the most prevalent serovar. Among Salmonella Enteritidis isolates, 95.2% belonged to Phage Type 4 (PT4 (20/21 and 4.8% to PT7 (1/21. Twenty-two (88% strains of Salmonella were resistant to at least one antimicrobial agent, generating eight different resistance patterns. The S. Typhimurium (n: 1 and S. Hadar (n: 3 isolates presented multiple resistance. Three S. Enteritidis isolates were susceptible to all antimicrobials tested, two were resistant only to tetracycline. The high prevalence of Salmonella in the broiler parts strenghtens the importance of the use of good manufacturing practices (GMP, and HACCP. The results also emphasize the need for the responsible use of antimicrobials in animal production.Este trabalho foi conduzido para avaliar a ocorrência de Salmonella em cortes de frango e para determinar o perfil de resistência antimicrobiana das cepas isoladas. Vinte e quatro (39,3% cortes de frango foram positivas para Salmonella, tendo sido isoladas vinte e cinco cepas de Salmonella, uma vez que em uma amostra isolaram-se dois sorovares. Salmonella Enteritidis foi o sorovar prevalente. Entre as Salmonella Enteritidis isoladas, 95,2% pertencem ao Fagotipo 4 (PT4 (20/21 e 4,8% ao PT7 (1/21. Vinte e duas (88% cepas de Salmonella foram resistentes a pelo menos um agente antimicrobiano e oito diferentes padrões de resistência foram observados. S. Typhimurium (n:1 e S. Hadar (n: 3, apresentaram múltipla resistência. Três cepas de S. Enteritidis foram sensíveis a todos os antimicrobianos e duas resistentes somente a tetraciclina. A elevada ocorr

Salmonella Infections - Multiple Languages

Science.gov (United States)

... Are Here: Home → Multiple Languages → All Health Topics → Salmonella Infections URL of this page: https://medlineplus.gov/ ... V W XYZ List of All Topics All Salmonella Infections - Multiple Languages To use the sharing features ...

In Vitro Preparation And Testing Of Anti-Salmonella Vaccine Against Abortion In Sheep

Directory of Open Access Journals (Sweden)

Flore CHIRILA

2017-05-01

There have been two booster inoculations of the initial administration, 7 and 14 days after. Before each dose of vaccine, blood was sampled from the marginal auricular vein in order to control the immunogenicity by anti-somatic ˮOˮ serum antibody (Ab titration using slow microplate agglutination test (Widal reaction. After three inoculations with the vaccine variant 1, Ab serum titer reached 1/128, and in types 2 and 3, 1/512 after 2 inoculations, decreasing to 1/256 after the second booster administered with no immunomodulator.

Vaccines provided by family physicians.

Science.gov (United States)

Campos-Outcalt, Doug; Jeffcott-Pera, Michelle; Carter-Smith, Pamela; Schoof, Bellinda K; Young, Herbert F

2010-01-01

This study was conducted to document current immunization practices by family physicians. In 2008 the American Academy of Family Physicians (AAFP) conducted a survey among a random sample of 2,000 of its members who reported spending 80% or more of their time in direct patient care. The survey consisted of questions regarding the demographics of the practice, vaccines that are provided at the physicians' clinical site, whether the practice refers patients elsewhere for vaccines, and participation in the Vaccines for Children (VFC) program. The response rate was 38.5%, 31.8% after non-office-based respondents were deleted. A high proportion of respondents (80% or more) reported providing most routinely recommended child, adolescent, and adult vaccines at their practice sites. The exceptions were rotavirus vaccine for children and herpes zoster vaccine for adults., A significant proportion, however, reported referring elsewhere for some vaccines (44.1% for children and adolescent vaccines and 53.5% for adult vaccines), with the most frequent referral location being a public health department. A higher proportion of solo and 2-physician practices than larger practices reported referring patients. A lack of adequate payment was listed as the reason for referring patients elsewhere for vaccines by one-half of those who refer patients. One-half of responders do not participate in the VFC program. Provision of recommended vaccines by most family physicians remains an important service. Smaller practices have more difficulty offering a full array of vaccine products, and lack of adequate payment contributes to referring patients outside the medical home. The reasons behind the lack of participation in the VFC program deserve further study.

The Importance of Health Risk Communication in the Creation of the Anthrax Vaccine Immunization Program

National Research Council Canada - National Science Library

Freeman, Bradley

2001-01-01

... press. This paper suggests that a more proactive educational program with a greater utilization of health risk communication techniques would have reduced much of the negative reaction to the anthrax vaccine...

9 CFR 113.123 - Salmonella Dublin Bacterin.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Salmonella Dublin Bacterin. 113.123... Inactivated Bacterial Products § 113.123 Salmonella Dublin Bacterin. Salmonella Dublin Bacterin shall be prepared from a culture of Salmonella dublin which has been inactivated and is nontoxic. Each serial of...

Test results of Salmonella typing by the NRLs-Salmonella in the Member States of the EU and the EnterNet Laboratories - Collaborative study VI on typing of Salmonella

NARCIS (Netherlands)

Korver H; Raes M; Maas HME; Ward LR; Wannet WJB; Henken AM; MGB; LIS

2002-01-01

Test resultaten van Salmonella sero- en faagtypering en antimicrobiele gevoeligheidsbepalingen door de Nationale Referentie Laboratoria voor Salmonella in de Lidstaten van de Europese Unie en EnterNet Laboratoria: Ringonderzoek VI (2001) voor Salmonella. Een zesde ringonderzoek betreffende de

Survival of Salmonella Newport in oysters.

Science.gov (United States)

Morrison, Christopher M; Armstrong, Alexandra E; Evans, Sanford; Mild, Rita M; Langdon, Christopher J; Joens, Lynn A

2011-08-02

Salmonella enterica is the leading cause of laboratory-confirmed foodborne illness in the United States and raw shellfish consumption is a commonly implicated source of gastrointestinal pathogens. A 2005 epidemiological study done in our laboratory by Brands et al., showed that oysters in the United States are contaminated with Salmonella, and in particular, a specific strain of the Newport serovar. This work sought to further investigate the host-microbe interactions between Salmonella Newport and oysters. A procedure was developed to reliably and repeatedly expose oysters to enteric bacteria and quantify the subsequent levels of bacterial survival. The results show that 10 days after an exposure to Salmonella Newport, an average concentration of 3.7 × 10(3)CFU/g remains within the oyster meat, and even after 60 days there still can be more than 10(2)CFU/g remaining. However, the strain of Newport that predominated in the market survey done by Brands et al. does not survive within oysters or the estuarine environment better than any other strains of Salmonella we tested. Using this same methodology, we compared Salmonella Newport's ability to survive within oysters to a non-pathogenic strain of E. coli and found that after 10 days the concentration of Salmonella was 200-times greater than that of E. coli. We also compared those same strains of Salmonella and E. coli in a depuration process to determine if a constant 120 L/h flux of clean seawater could significantly reduce the concentration of bacteria within oysters and found that after 3 days the oysters retained over 10(4)CFU/g of Salmonella while the oysters exposed to the non-pathogenic strain of E. coli contained 100-times less bacteria. Overall, the results of this study demonstrate that any of the clinically relevant serovars of Salmonella can survive within oysters for significant periods of time after just one exposure event. Based on the drastic differences in survivability between Salmonella and a non

Cost-effectiveness analysis of introducing universal human papillomavirus vaccination of girls aged 11 years into the National Immunization Program in Brazil.

Science.gov (United States)

Novaes, Hillegonda Maria Dutilh; de Soárez, Patrícia Coelho; Silva, Gulnar Azevedo; Ayres, Andreia; Itria, Alexander; Rama, Cristina Helena; Sartori, Ana Marli Christovam; Clark, Andrew D; Resch, Stephen

2015-05-07

To evaluate the impact and cost-effectiveness of introducing universal human papillomavirus (HPV) vaccination into the National Immunization Program (NIP) in Brazil. The Excel-based CERVIVAC decision support model was used to compare two strategies: (1) status quo (with current screening program) and (2) vaccination of a cohort of 11-year-old girls. National parameters for the epidemiology and costs of cervical cancer were estimated in depth. The estimates were based on data from the health information systems of the public health system, the PNAD 2008 national household survey, and relevant scientific literature on Brazil. Costs are expressed in 2008 United States dollars (US$), and a 5% discount rate is applied to both future costs and future health benefits. Introducing the HPV vaccine would reduce the burden of disease. The model estimated there would be 229 deaths avoided and 6677 disability-adjusted life years (DALYs) averted in the vaccinated cohort. The incremental cost-effectiveness ratios (ICERs) per DALY averted from the perspectives of the government (US$ 7663), health system (US$ 7412), and society (US$ 7298) would be considered cost-effective, according to the parameters adopted by the World Health Organization. In the sensitivity analysis, the ICERs were most sensitive to variations in discount rate, disease burden, vaccine efficacy, and proportion of cervical cancer caused by types 16 and 18. However, universal HPV vaccination remained a cost-effective strategy in most variations of the key estimates. Vaccine introduction could contribute additional benefits in controlling cervical cancer, but it requires large investments by the NIP. Among the essential conditions for attaining the expected favorable results are immunization program sustainability, equity in a population perspective, improvement of the screening program, and development of a surveillance system. Copyright © 2014 Elsevier Ltd. All rights reserved.

Prediction of Salmonella carcass contamination by a comparative quantitative analysis of E. coli and Salmonella during pig slaughter

DEFF Research Database (Denmark)

Nauta, Maarten; Barfod, Kristen; Hald, Tine

2013-01-01

Salmonella concentrations. It is concluded that the faecal carriage of Salmonella together with the faecal contamination of carcasses, as predicted from E. coli data in the animal faeces and hygiene performance of the slaughterhouse, is not sufficient to explain carcass contamination with Salmonella. Our...... extensive data set showed that other factors than the observed faecal carriage of Salmonella by the individual animals brought to slaughter, play a more important role in the Salmonella carcass contamination of pork.......Faecal contamination of carcasses in the slaughterhouse is generally considered to be the source of Salmonella on pork. In this study the hygiene indicator Escherichia coli is used to quantify faecal contamination of carcasses and it is hypothesized that it can be used to predict the quantitative...

Effects of the introduction of new vaccines in Guinea-Bissau on vaccine coverage, vaccine timeliness, and child survival: an observational study

OpenAIRE

Fisker, Ane B; Hornshøj, Linda; Rodrigues, Amabelia; Balde, Ibraima; Fernandes, Manuel; Benn, Christine S; Aaby, Peter

2014-01-01

Background: In 2008, the GAVI Alliance funded the introduction of new vaccines (including pentavalent diphtheria-tetanus-pertussis [DTP] plus hepatitis B and Haemophilus influenzae type b antigens) in Guinea-Bissau. The introduction was accompanied by increased vaccination outreach services and a more restrictive wastage policy, including only vaccinating children younger than 12 months. We assessed coverage of all vaccines in the Expanded Program on Immunizations before and after the new vac...

The Peru Cervical Cancer Screening Study (PERCAPS): the design and implementation of a mother/daughter screen, treat, and vaccinate program in the Peruvian jungle.

Science.gov (United States)

Abuelo, Carolina E; Levinson, Kimberly L; Salmeron, Jorge; Sologuren, Carlos Vallejos; Fernandez, Maria Jose Vallejos; Belinson, Jerome L

2014-06-01

Peru struggles to prevent cervical cancer (CC). In the jungle, prevention programs suffer from significant barriers although technology exists to detect CC precursors. This study used community based participatory research (CBPR) methods to overcome barriers. The objective was to evaluate the utility of CBPR techniques in a mother-child screen/treat and vaccinate program for CC prevention in the Peruvian jungle. The CC prevention program used self-sampling for human papillomavirus (HPV) for screening, cryotherapy for treatment and the HPV vaccine Gardasil for vaccination. Community health leaders (HL) from around Iquitos participated in a two half day educational course. The HLs then decided how to implement interventions in their villages or urban sectors. The success of the program was measured by: (1) ability of the HLs to determine an implementation plan, (2) proper use of research forms, (3) participation and retention rates, and (4) participants' satisfaction. HLs successfully registered 320 women at soup kitchens, schools, and health posts. Screening, treatment, and vaccination were successfully carried out using forms for registration, consent, and results with minimum error. In the screen/treat intervention 100% of participants gave an HPV sample and 99.7% reported high satisfaction; 81% of HPV + women were treated, and 57% returned for 6-month followup. Vaccine intervention: 98% of girls received the 1st vaccine, 88% of those received the 2nd, and 65% the 3rd. CBPR techniques successfully helped implement a screen/treat and vaccinate CC prevention program around Iquitos, Peru. These techniques may be appropriate for large-scale preventive health-care interventions.

Molecular diagnosis of Salmonella typhi and its virulence in suspected typhoid blood samples through nested multiplex PCR.

Science.gov (United States)

Prabagaran, Solai Ramatchandirane; Kalaiselvi, Vellingiri; Chandramouleeswaran, Naganathan; Deepthi, Krishnan Nair Geetha; Brahmadathan, Kootallur Narayanan; Mani, Mariappa

2017-08-01

A nested multiplex polymerase chain reaction (PCR) based diagnosis was developed for the detection of virulent Salmonella typhi in the blood specimens from patients suspected for typhoid fever. After the Widal test, two pairs of primers were used for the detection of flagellin gene (fliC) of S. typhi. Among them, those positive for fliC alone were subjected to identification of genes in Via B operon of Salmonella Pathogenesity Island (SPI-7) where four primer pairs were used to detect tviA and tviB genes. Among 250 blood samples tested, 115 were positive by fliC PCR; 22 of these were negative for tviA and tviB. Hence, the method described here can be used to diagnose the incidence of Vi-negative serovar typhi especially in endemic regions where the Vi vaccine is administered. Copyright © 2017 Elsevier B.V. All rights reserved.

Decision support in vaccination policies.

Science.gov (United States)

Piso, B; Wild, C

2009-10-09

Looking across boarders reveals that the national immunization programs of various countries differ in their vaccination schedules and decisions regarding the implementation and funding of new vaccines. The aim of this review is to identify decision aids and crucial criteria for a rational decision-making process on vaccine introduction and to develop a theoretical framework for decision-making based on available literature. Systematic literature search supplemented by hand-search. We identified five published decision aids for vaccine introduction and program planning in industrialized countries. Their comparison revealed an overall similarity with some differences in the approach as well as criteria. Burden of disease and vaccine characteristics play a key role in all decision aids, but authors vary in their views on the significance of cost-effectiveness analyses. Other relevant factors that should be considered before vaccine introduction are discussed to highly differing extents. These factors include the immunization program itself as well as its conformity with other programs, its feasibility, acceptability, and equity, as well as ethical, legal and political considerations. Assuming that the most comprehensive framework possible will not provide a feasible tool for decision-makers, we suggest a stepwise procedure. Though even the best rational approach and most comprehensive evaluation is limited by remaining uncertainties, frameworks provide at least a structured approach to evaluate the various aspects of vaccine implementation decision-making. This process is essential in making consistently sound decisions and will facilitate the public's confidence in the decision and its realization.

Serotype tracking of Salmonella through integrated broiler chicken operations.

Science.gov (United States)

Bailey, J S; Cox, N A; Craven, S E; Cosby, D E

2002-05-01

The widespread presence of Salmonella in all phases of broiler chicken production and processing is well documented. However, little information is available to indicate the identity and movement of specific serotypes of Salmonella through the different phases of an integrated operation. In this study, samples were collected from the breeder farm, from the hatchery, from the previous grow-out flock, from the flock during grow-out, and from carcasses after processing. Salmonella were recovered from 6, 98, 24, 60, and 7% of the samples, respectively, in the first trial and from 7, 98, 26, 22, and 36% of the samples, respectively, in the second trial. Seven different serotypes were identified in the first trial, and 12 different serotypes were identified in the second trial. For both trials there was poor correlation between the serotypes found in the breeder farms and those found in the hatchery. This finding and the fact that similar serotypes were found in the hatchery in both trials suggests that there was an endemic population of Salmonella in the hatchery. An association between the serotypes found in the hatchery and those found on the final processed carcasses was observed in both trials. This study confirms that a successful intervention program for broiler production operations must be multifaceted, with one component being disinfection in the hatchery.

Mexico introduces pentavalent vaccine.

Science.gov (United States)

1999-08-01

Combination vaccines have been introduced in Mexico. The national immunization program has incorporated the measles-mumps-rubella (MMR) vaccines in 1998, and the pentavalent vaccine in 1999. The two categories of antigen composition in combination vaccines are: 1) multiple different antigenic types of a single pathogen, such as the 23 valent pneumococcal polysaccharide vaccine, and 2) antigens from different pathogens causing different diseases, such as the DPT and MMR vaccines. Pentavalent vaccines are included in the second category. The vaccine protects against diphtheria, tetanus, pertussis, hepatitis B, and other diseases produced by Haemophilus influenzae type b (Hib). Combined diphtheria, tetanus, pertussis, hepatitis B, and Haemophilus influenza type b (DTP-HB/Hib) vaccine has been distributed to 87% of Mexican children under 1 year of age. Over 800,000 doses of pentavalent vaccine have been administered.

Test results of Salmonella typing by the NRLs-Salmonella in the Member States of the EU and the EnterNet Laboratories - Collaborative study VI on typing of Salmonella

NARCIS (Netherlands)

Korver H; Raes M; Maas HME; Ward LR; Wannet WJB; Henken AM; PHLS-Colindale/London; MGB; LIS

2002-01-01

Test results of Salmonella sero- and phage typing and antimicrobial susceptibility testing by the National Reference Laboratories for Salmonella in the Member States of the European Union and the EnterNet Laboratories: Collaborative study VI (2001) for Salmonella. The sixth collaborative typing

Vaccination coverage against pertussis in pregnant women of Catalonia in the first year of implementation of the immunisation program.

Science.gov (United States)

Fernández-Cano, María Isabel; Espada-Trespalacios, Xavier; Reyes-Lacalle, Azahara; Manresa Domínguez, Josep Maria; Armadans-Gil, Lluís; Campins-Martí, Magda; Falguera-Puig, Gemma; Toran Monserrat, Pere

2017-11-01

The re-emergence of pertussis and the severity of its complications in infants younger than 3 months, were determining factors for starting a vaccination program for pregnant women in the third trimester of gestation in Catalonia in February 2014. This was the first autonomous community to introduce it in Spain. The aim of the study was to estimate the coverage of the program in its first year of implementation. A retrospective analysis was performed on the data from the Primary Care Centre computerised medical records of pregnant women attending Sexual and Reproductive Health Care centres of the Metropolitan Nord area of the province of Barcelona, part of the Catalan Institute of Health. The overall coverage was estimated, as well as the sociodemographic variables of Tdap vaccination of women who had registered a delivery of a live birth between August 2014 and August 2015. A total of 6,697 deliveries of live births were recorded, and 1,713 pregnant women were vaccinated, which represented an overall coverage of 25.6% (95% CI; 24.1-26.1). Vaccination coverage was higher in pregnant women under 18 years and Spanish women (P=.018 and P=.036, respectively). The estimation of vaccine coverage against pertussis in pregnant women in the third trimester of pregnancy, after the first year of implementation of the program in a health area of Catalonia was lower than the objective set. Strategies need to be designed in order to improve program coverage. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Thermal inactivation of eight Salmonella serotypes on dry corn flour.

OpenAIRE

VanCauwenberge, J E; Bothast, R J; Kwolek, W F

1981-01-01

Dry heat was used to inactivate Salmonella newington, Salmonella typhimurium, Salmonella anatum, Salmonella kentucky, Salmonella cubana, Salmonella seftenberg, Salmonella thompson, and Salmonella tennessee in corn flour at 10 and 15% moisture. The flour was spray inoculated at 10(5) Salmonella cells per g and then stored at 49 degrees C (120 degrees F); viable Salmonella cells were counted on Trypticase (BBL Microbiology Systems) soy agar plates every 30 min for the first 4 h and then at 4-h ...

Influenza Vaccinations, Fall 2009: Model School-Located Vaccination Clinics

Science.gov (United States)

Herl Jenlink, Carolyn; Kuehnert, Paul; Mazyck, Donna

2010-01-01

The 2009 H1N1 influenza virus presented a major challenge to health departments, schools, and other community partners to effectively vaccinate large numbers of Americans, primarily children. The use of school-located vaccination (SLV) programs to address this challenge led health departments and schools to become creative in developing models for…

Vaccines for human papillomavirus infection: A critical analysis

Directory of Open Access Journals (Sweden)

Nath Amiya

2009-01-01

Full Text Available This article takes a critical look at the pros and cons of human papillomavirus (HPV vaccines. There is enough evidence to suggest that the prophylactic vaccines are efficacious in preventing various benign and malignant conditions (including cervical cancers caused by HPV. Even though the vaccine is costly, hypothetical analysis has shown that HPV vaccination will be cost effective in the long run. Therapeutic HPV vaccines used to treat established disease are still undergoing evaluation in clinical studies, and results seem to be encouraging. Although several countries have started mandatory vaccination programs with the prophylactic HPV vaccines, conservatives have voiced concerns regarding the moral impact of such vaccination programs.

Prevalence of antimicrobial resistance of non-typhoidal Salmonella serovars in retail aquaculture products.

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Zhang, Jianmin; Yang, Xiaowei; Kuang, Dai; Shi, Xianming; Xiao, Wenjia; Zhang, Jing; Gu, Zhen; Xu, Xuebin; Meng, Jianghong

2015-10-01

Aquaculture products can become sources of Salmonella by exposure to contaminated water or through processing practices, thus representing a public health hazard. A study was conducted on Salmonella contamination in aquaculture products sampled from marketplaces and retailers in Shanghai, China. A total of 730 samples (including fish, shellfish, bullfrog, clam, shrimp and others) were obtained from 2006 to 2011. Among them, 217 (29.7%) were positive for Salmonella. Thirty-eight serovars were identified in the 217 Salmonella isolates. The most prevalent were Salmonella Aberdeen (18.4%), S. Wandsworth (12.0%), S. Thompson (9.2%), S. Singapore (5.5%), S. Stanley (4.6%), S. Schwarzengrund (4.6%), S. Hvittingfoss (4.1%) and S. Typhimurium (4.1%). Many resistant isolates were detected, with 69.6% resistant to at least one antimicrobial drug. We observed high resistance to sulfonamides (56.5%), tetracycline (34.1%), streptomycin (28.6%), ampicillin (23.5%) and nalidixic acid (21.2%). Lower levels of resistance were found for gentamicin (3.2%), ciprofloxacin (2.3%), ceftiofur (1.3%), cefotaxime (0.9%), ceftazidime (0.5%) and cefepime (0.5%). A total of 43.3% of the Salmonella isolates were multidrug-resistant and 44 different resistance patterns were found. This study provided data on the prevalence, serovars and antimicrobial resistance of Salmonella from retail aquaculture products in Shanghai, and indicated the need for monitoring programs for microbiologic safety in such projects and for more prudent drug use in aquaculture production in order to reduce the risk of development and spread of antimicrobial resistance. Copyright © 2015 Elsevier B.V. All rights reserved.

The impact of making vaccines thermostable in Niger's vaccine supply chain.

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Lee, Bruce Y; Cakouros, Brigid E; Assi, Tina-Marie; Connor, Diana L; Welling, Joel; Kone, Souleymane; Djibo, Ali; Wateska, Angela R; Pierre, Lionel; Brown, Shawn T

2012-08-17

Determine the effects on the vaccine cold chain of making different types of World Health Organization (WHO) Expanded Program on Immunizations (EPI) vaccines thermostable. Utilizing a detailed computational, discrete-event simulation model of the Niger vaccine supply chain, we simulated the impact of making different combinations of the six current EPI vaccines thermostable. Making any EPI vaccine thermostable relieved existing supply chain bottlenecks (especially at the lowest levels), increased vaccine availability of all EPI vaccines, and decreased cold storage and transport capacity utilization. By far, the most substantial impact came from making the pentavalent vaccine thermostable, increasing its own vaccine availability from 87% to 97% and the vaccine availabilities of all other remaining non-thermostable EPI vaccines to over 93%. By contrast, making each of the other vaccines thermostable had considerably less effect on the remaining vaccines, failing to increase the vaccine availabilities of other vaccines to more than 89%. Making tetanus toxoid vaccine along with the pentavalent thermostable further increased the vaccine availability of all EPI vaccines by at least 1-2%. Our study shows the potential benefits of making any of Niger's EPI vaccines thermostable and therefore supports further development of thermostable vaccines. Eliminating the need for refrigerators and freezers should not necessarily be the only benefit and goal of vaccine thermostability. Rather, making even a single vaccine (or some subset of the vaccines) thermostable could free up significant cold storage space for other vaccines, and thereby help alleviate supply chain bottlenecks that occur throughout the world. Copyright © 2012 Elsevier Ltd. All rights reserved.

Vaccination Perceptions of College Students: With and without Vaccination Waiver.

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Jadhav, Emmanuel D; Winkler, Danielle L; Anderson, Billie S

2018-01-01

The resurgence of vaccine preventable diseases occurs more often among intentionally unvaccinated individuals, placing at direct risk young adults not caught up on vaccinations. The objectives of this study were to characterize the sociodemographic characteristics of young adults with and without vaccination waivers and identify their perceived benefits, barriers, and influencers of vaccination. Young adults ( n  = 964) from a Midwestern rural university responded to a survey (fall 2015-spring 2016) designed to identify their perception toward vaccination. Instrument consistency was measured using the Cronbach α-scores. The Chi-square test was used to test any sociodemographic differences and Mann-Whitney U -tests results for differences between exempt and non-exempt students. Analysis occurred in spring 2017. A little over one-third of young adults with a vaccination waiver were not up to date on their vaccinations, and think that vaccinations can cause autism. The biggest identifiable benefit was effective control against disease. The surveyed young adults ranked the out of pocket cost associated with vaccination as the most important barrier and safe and easy to use vaccines as the most important influencer of vaccination. Young adults who have had a vaccination waiver appear to not be up to date on their vaccinations. Vaccine administration programs, such as university campus clinics, would benefit from addressing perceptions unique to young adults with and without a vaccine waiver. This would subsequently better provide young adults a second shot for getting appropriately caught up on vaccinations.

Assessment of Salmonella survival in dry-cured Italian salami.

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Bonardi, S; Bruini, I; Bolzoni, L; Cozzolino, P; Pierantoni, M; Brindani, F; Bellotti, P; Renzi, M; Pongolini, S

2017-12-04

The inactivation of Salmonella during curing of Italian traditional pork salami was investigated. A total of 150 batches of ground raw meat (GRM) used for salami manufacturing by four producers were tested for Salmonella by real-time PCR followed by ISO 6579 cultural confirmation and MPN enumeration. Salami produced with Salmonella positive GRMs were re-tested at the end of their curing period. Aw, pH and NaCl content were also measured. Detection of Salmonella was performed testing both 25 and 50g of the samples. By Real-Time PCR 37% of the GRMs resulted positive, but cultural detection of Salmonella was obtained in 14% of the samples only. Salmonella enumeration ranged from 31 MPN/g to Salmonella in 100% of all positive samples, vs. 62% of ISO-25g. Salami made of the contaminated GRMs were 29% Salmonella-positive, as most batches of salami produced with Salmonella-positive GRMs resulted negative after regular curing (20-48days). Overall, 13% of salami produced with Salmonella-contaminated GRMs were positive. They belonged to six batches, which turned out negative after prolonged curing ranging between 49 and 86days. Salmonella enumeration in salami ranged from 8.7 MPN/g to Salmonella in cured salami (p value: >0.05). The most common Salmonella serovars in GRMs were Derby (52%), Typhimurium monophasic variant 4, (Barbuti et al., 1993), 12:i:- (19%) and Stanley (10%). Salmonella Derby (56%), London, Branderup, Panama (13%, respectively) and Goldcoast (6%) were most frequent in cured salami. The study showed negative correlation between real-time CT values and cultural confirmation of Salmonella, as well as the importance of sample size for Salmonella detection. Among considered factors with possible effect on the occurrence of Salmonella in salami, statistical analysis revealed a role for aw in salami and for Salmonella load in GRMs, while pH and NaCl content did not significantly affect the probability of finding Salmonella in dry-cured salami in the context of

Autophagy Facilitates Salmonella Replication in HeLa Cells

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Yu, Hong B.; Croxen, Matthew A.; Marchiando, Amanda M.; Ferreira, Rosana B. R.; Cadwell, Ken; Foster, Leonard J.; Finlay, B. Brett

2014-01-01

ABSTRACT Autophagy is a process whereby a double-membrane structure (autophagosome) engulfs unnecessary cytosolic proteins, organelles, and invading pathogens and delivers them to the lysosome for degradation. We examined the fate of cytosolic Salmonella targeted by autophagy and found that autophagy-targeted Salmonella present in the cytosol of HeLa cells correlates with intracellular bacterial replication. Real-time analyses revealed that a subset of cytosolic Salmonella extensively associates with autophagy components p62 and/or LC3 and replicates quickly, whereas intravacuolar Salmonella shows no or very limited association with p62 or LC3 and replicates much more slowly. Replication of cytosolic Salmonella in HeLa cells is significantly decreased when autophagy components are depleted. Eventually, hyperreplication of cytosolic Salmonella potentiates cell detachment, facilitating the dissemination of Salmonella to neighboring cells. We propose that Salmonella benefits from autophagy for its cytosolic replication in HeLa cells. PMID:24618251

Schools as potential vaccination venue for vaccines outside regular EPI schedule: results from a school census in Pakistan

NARCIS (Netherlands)

Soofi, S.B.; Haq, I.U.; Khan, M.I.; Siddiqui, M.B.; Mirani, M.; Tahir, R.; Hussain, I.; Puri, M.K.; Suhag, Z.H.; Khowaja, A.R.; Lasi, A.R.; Clemens, J.D.; Favorov, M.; Ochiai, R.L.; Bhutta, Z.A.

2012-01-01

BACKGROUND: Vaccines are the most effective public health intervention. Expanded Program on Immunization (EPI) provides routine vaccination in developing countries. However, vaccines that cannot be given in EPI schedule such as typhoid fever vaccine need alternative venues. In areas where school

Study on Feasibility and Logistics of Vaccination with Typhoid Vi-vaccine on School Children in North Jakarta Indonesia: Analysis of the Vaccination Cost

OpenAIRE

Massie, Roy G.A

2011-01-01

Background: In recent years, Indonesia government has become increasingly concerned with the issues of financing childhood vaccines and immunization programs including vaccine for typhoid fever. The objective of the analysis is to provide alternative resources and to provide understandable data generated from the Study on Feasibility and Logistics of Vaccination School Age Children With Typhoid Vi-Vaccine in North Jakarta Indonesia. Methods: The analysis was focus on measurement of the cost ...

Projected economic evaluation of the national implementation of a hypothetical HIV vaccination program among adolescents in South Africa, 2012

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Nishila Moodley

2016-04-01

Full Text Available Abstract Background Adolescents in South Africa are at high risk of acquiring HIV. The HIV vaccination of adolescents could reduce HIV incidence and mortality. The potential impact and cost-effectiveness of a national school-based HIV vaccination program among adolescents was determined. Method The national HIV disease and cost burden was compared with (intervention and without HIV vaccination (comparator given to school-going adolescents using a semi-Markov model. Life table analysis was conducted to determine the impact of the intervention on life expectancy. Model inputs included measures of disease and cost burden and hypothetical assumptions of vaccine characteristics. The base-case HIV vaccine modelled cost at US$ 12 per dose; vaccine efficacy of 50 %; duration of protection of 10 years achieved at a coverage rate of 60 % and required annual boosters. Incremental cost-effectiveness ratios (ICER were calculated using life years gained (LYG serving as the outcome measure. Sensitivity analyses were conducted on the vaccine characteristics to assess parameter uncertainty. Results The HIV vaccination model yielded an ICER of US$ 5 per LYG (95 % CI ZAR 2.77–11.61 compared with the comparator, which is considerably less than the national willingness-to-pay threshold of cost-effectiveness. This translated to an 11 % increase in per capita costs from US$ 80 to US$ 89. National implementation of this intervention could potentially result in an estimated cumulative gain of 23.6 million years of life (95 % CI 8.48–34.3 million years among adolescents age 10–19 years that were vaccinated. The 10 year absolute risk reduction projected by vaccine implementation was 0.42 % for HIV incidence and 0.41 % for HIV mortality, with an increase in life expectancy noted across all age groups. The ICER was sensitive to the vaccine efficacy, coverage and vaccine pricing in the sensitivity analysis. Conclusions A national HIV vaccination program would

Salmonella Typhi Colonization Provokes Extensive Transcriptional Changes Aimed at Evading Host Mucosal Immune Defense During Early Infection of Human Intestinal Tissue

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K.P. Nickerson

2018-05-01

Full Text Available Commensal microorganisms influence a variety of host functions in the gut, including immune response, glucose homeostasis, metabolic pathways and oxidative stress, among others. This study describes how Salmonella Typhi, the pathogen responsible for typhoid fever, uses similar strategies to escape immune defense responses and survive within its human host. To elucidate the early mechanisms of typhoid fever, we performed studies using healthy human intestinal tissue samples and “mini-guts,” organoids grown from intestinal tissue taken from biopsy specimens. We analyzed gene expression changes in human intestinal specimens and bacterial cells both separately and after colonization. Our results showed mechanistic strategies that S. Typhi uses to rearrange the cellular machinery of the host cytoskeleton to successfully invade the intestinal epithelium, promote polarized cytokine release and evade immune system activation by downregulating genes involved in antigen sampling and presentation during infection. This work adds novel information regarding S. Typhi infection pathogenesis in humans, by replicating work shown in traditional cell models, and providing new data that can be applied to future vaccine development strategies. Keywords: Typhoid fever, Salmonella, Snapwell™ system, Human tissue, Terminal ileum, Immune system, Innate immunity, Immune evasion, Host-pathogen interaction, Vaccine development, Intestinal organoids, Organoid monolayer

Using a Human Challenge Model of Infection to Measure Vaccine Efficacy: A Randomised, Controlled Trial Comparing the Typhoid Vaccines M01ZH09 with Placebo and Ty21a.

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Darton, Thomas C; Jones, Claire; Blohmke, Christoph J; Waddington, Claire S; Zhou, Liqing; Peters, Anna; Haworth, Kathryn; Sie, Rebecca; Green, Christopher A; Jeppesen, Catherine A; Moore, Maria; Thompson, Ben A V; John, Tessa; Kingsley, Robert A; Yu, Ly-Mee; Voysey, Merryn; Hindle, Zoe; Lockhart, Stephen; Sztein, Marcelo B; Dougan, Gordon; Angus, Brian; Levine, Myron M; Pollard, Andrew J

2016-08-01

Typhoid persists as a major cause of global morbidity. While several licensed vaccines to prevent typhoid are available, they are of only moderate efficacy and unsuitable for use in children less than two years of age. Development of new efficacious vaccines is complicated by the human host-restriction of Salmonella enterica serovar Typhi (S. Typhi) and lack of clear correlates of protection. In this study, we aimed to evaluate the protective efficacy of a single dose of the oral vaccine candidate, M01ZH09, in susceptible volunteers by direct typhoid challenge. We performed a randomised, double-blind, placebo-controlled trial in healthy adult participants at a single centre in Oxford (UK). Participants were allocated to receive one dose of double-blinded M01ZH09 or placebo or 3-doses of open-label Ty21a. Twenty-eight days after vaccination, participants were challenged with 104CFU S. Typhi Quailes strain. The efficacy of M01ZH09 compared with placebo (primary outcome) was assessed as the percentage of participants reaching pre-defined endpoints constituting typhoid diagnosis (fever and/or bacteraemia) during the 14 days after challenge. Ninety-nine participants were randomised to receive M01ZH09 (n = 33), placebo (n = 33) or 3-doses of Ty21a (n = 33). After challenge, typhoid was diagnosed in 18/31 (58.1% [95% CI 39.1 to 75.5]) M01ZH09, 20/30 (66.7% [47.2 to 87.2]) placebo, and 13/30 (43.3% [25.5 to 62.6]) Ty21a vaccine recipients. Vaccine efficacy (VE) for one dose of M01ZH09 was 13% [95% CI -29 to 41] and 35% [-5 to 60] for 3-doses of Ty21a. Retrospective multivariable analyses demonstrated that pre-existing anti-Vi antibody significantly reduced susceptibility to infection after challenge; a 1 log increase in anti-Vi IgG resulting in a 71% decrease in the hazard ratio of typhoid diagnosis ([95% CI 30 to 88%], p = 0.006) during the 14 day challenge period. Limitations to the study included the requirement to limit the challenge period prior to treatment to 2

Are Salmonella-Induced Gastroenteritis Neglected in Developing Countries? Feedback from Microbiological Investigations in N'Djamena Hospitals, Chad.

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Djim-Adjim Tabo

Full Text Available Salmonella is considered to be one of the main pathogens causing human gastroenteritis worldwide. Looking for Salmonella in Africa in patients suffering from gastroenteritis is rather unusual, and the use of antibiotics is not subject to any regulation. This study intends for stressing the possible prominent importance of Salmonella in digestive diseases in Africa as well as identifying antimicrobial resistance of Salmonella isolates from faeces samples of human origin. All samples were collected from five N'Djamena hospitals, from patients suffering from diarrhoea. The collecting was undertaken over two periods of six months each: from August 2010 to January 2011 and from September 2011 to February 2012. Salmonella isolates were obtained by standard cultivation and serotyping methods. A total of 43 Salmonella isolates were identified, belonging to 21 different serovars. The most prevalent serovar was Salmonella Stanleyville (n = 7, followed by S. Anatum (n = 4 and S. Kottbus (n = 3. The other serovars were under-represented. The majority of these isolates were susceptible to all antibiotics tested (CLSI Standards, except two S. Enteritidis isolates that exhibited resistance to fluoroquinolones. The different serovars and antibiotic resistance profiles that were observed highlight the substantial diversity of Salmonella in N'Djamena, Chad. Roughly, one out of ten patients who consulted for gastroenteritis was shedding Salmonella spp. and none of them would have been diagnosed outside the context of this research program. This study may encourage local clinicians to explore more often salmonellosis suspicion in their daily practice.

Can influenza epidemics be prevented by voluntary vaccination?

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Raffaele Vardavas

2007-05-01

Full Text Available Previous modeling studies have identified the vaccination coverage level necessary for preventing influenza epidemics, but have not shown whether this critical coverage can be reached. Here we use computational modeling to determine, for the first time, whether the critical coverage for influenza can be achieved by voluntary vaccination. We construct a novel individual-level model of human cognition and behavior; individuals are characterized by two biological attributes (memory and adaptability that they use when making vaccination decisions. We couple this model with a population-level model of influenza that includes vaccination dynamics. The coupled models allow individual-level decisions to influence influenza epidemiology and, conversely, influenza epidemiology to influence individual-level decisions. By including the effects of adaptive decision-making within an epidemic model, we can reproduce two essential characteristics of influenza epidemiology: annual variation in epidemic severity and sporadic occurrence of severe epidemics. We suggest that individual-level adaptive decision-making may be an important (previously overlooked causal factor in driving influenza epidemiology. We find that severe epidemics cannot be prevented unless vaccination programs offer incentives. Frequency of severe epidemics could be reduced if programs provide, as an incentive to be vaccinated, several years of free vaccines to individuals who pay for one year of vaccination. Magnitude of epidemic amelioration will be determined by the number of years of free vaccination, an individuals' adaptability in decision-making, and their memory. This type of incentive program could control epidemics if individuals are very adaptable and have long-term memories. However, incentive-based programs that provide free vaccination for families could increase the frequency of severe epidemics. We conclude that incentive-based vaccination programs are necessary to control

Implementation of an HPV vaccination program in Eldoret, Kenya: results from a qualitative assessment by key stakeholders

OpenAIRE

Vermandere, Heleen; Naanyu, Violet; Degomme, Olivier; Michielsen, Kristien

2015-01-01

Background: Cervical cancer strikes hard in low-resource regions yet primary prevention is still rare. Pilot projects have however showed that Human Papillomavirus (HPV) vaccination programs can attain high uptake. Nevertheless, a study accompanying a vaccination demonstration project in Eldoret, Kenya, revealed less encouraging outcomes: uptake during an initial phase targeting ten schools (i.e., 4000 eligible girls), was low and more schools had to be included to reach the proposed number o...

Final analysis of a study assessing genital human papillomavirus genoprevalence in young Australian women, following eight years of a national vaccination program.

Science.gov (United States)

Garland, Suzanne M; Cornall, Alyssa M; Brotherton, Julia M L; Wark, John D; Malloy, Michael J; Tabrizi, Sepehr N

2018-05-31

The VACCINE [Vaccine Against Cervical Cancer Impact and Effectiveness] study evaluated the prevalence of quadrivalent vaccine-targeted human papillomavirus (HPV) genotypes (HPV 6, 11, 16, 18) amongst young women of vaccine-eligible age. Between October 2011 - June 2015, women aged 18-25 years from Victoria, Australia, were recruited through targeted advertising on the social networking website Facebook. Participants completed an online questionnaire and provided a self-collected vaginal swab for HPV DNA detection and genotyping (Linear Array HPV genotyping assay). Self-reported HPV vaccination details were verified with the National HPV Vaccination Program Register (NHVPR). Of 1223 who agreed to participate, 916 (74.9%) completed the survey and, for 1007 (82.3%) sexually-active participants, 744 (73.9%) returned the self-collected swab, of which 737 contained detectable DNA. 184/737 (25.0%) were positive for HPV. Vaccine-targeted HPV genotypes were detected in only 13 (1.7%) women: 11 HPV 16 (six vaccinated after sexual debut, five unvaccinated) and two HPV 6. Prevalence of any of HPV 31/33/45 collectively was 2.9%, varying significantly by vaccination status (fully 2.0%, unvaccinated 6.8%; p = 0.01). Vaccination rates among the sexually-active cohort were high, with 65.6%, 71.6% and 74.2% of participants having received three, at least two or at least one dose of vaccine, respectively. Of women self-reporting HPV vaccination, the NHVPR confirmed one or more doses were received in 90%. Strong associations were observed between vaccination status, age, language spoken at home and country of birth, as well as between HPV detection and the number of male sexual partners. Surveillance five to eight years' post-initiation of a national HPV vaccination program demonstrated a consistent and very low prevalence of vaccine-related HPV genotypes and some evidence of cross protection against related types amongst vaccine-eligible women from Victoria, Australia

Health and Economic Impact of Switching from a 4-Valent to a 9-Valent HPV Vaccination Program in the United States.

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Brisson, Marc; Laprise, Jean-François; Chesson, Harrell W; Drolet, Mélanie; Malagón, Talía; Boily, Marie-Claude; Markowitz, Lauri E

2016-01-01

Randomized clinical trials have shown the 9-valent human papillomavirus (HPV) vaccine to be highly effective against types 31/33/45/52/58 compared with the 4-valent. Evidence on the added health and economic benefit of the 9-valent is required for policy decisions. We compare population-level effectiveness and cost-effectiveness of 9- and 4-valent HPV vaccination in the United States. We used a multitype individual-based transmission-dynamic model of HPV infection and disease (anogenital warts and cervical, anogenital, and oropharyngeal cancers), 3% discount rate, and societal perspective. The model was calibrated to sexual behavior and epidemiologic data from the United States. In our base-case, we assumed 95% vaccine-type efficacy, lifelong protection, and a cost/dose of $145 and $158 for the 4- and 9-valent vaccine, respectively. Predictions are presented using the mean (80% uncertainty interval [UI] = 10(th)-90(th) percentiles) of simulations. Under base-case assumptions, the 4-valent gender-neutral vaccination program is estimated to cost $5500 (80% UI = 2400-9400) and $7300 (80% UI = 4300-11 000)/quality-adjusted life-year (QALY) gained with and without cross-protection, respectively. Switching to a 9-valent gender-neutral program is estimated to be cost-saving irrespective of cross-protection assumptions. Finally, the incremental cost/QALY gained of switching to a 9-valent gender-neutral program (vs 9-valent girls/4-valent boys) is estimated to be $140 200 (80% UI = 4200->1 million) and $31 100 (80% UI = 2100->1 million) with and without cross-protection, respectively. Results are robust to assumptions about HPV natural history, screening methods, duration of protection, and healthcare costs. Switching to a 9-valent gender-neutral HPV vaccination program is likely to be cost-saving if the additional cost/dose of the 9-valent is less than $13. Giving females the 9-valent vaccine provides the majority of benefits of a gender-neutral strategy. © The Author

Study of Salmonella Typhimurium infection in laying hens

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Kapil eChousalkar

2016-02-01

Full Text Available Members of Salmonella enterica are frequently involved in egg and egg product related human food poisoning outbreaks worldwide. In Australia, Salmonella Typhimurium is frequently involved in egg and egg product related foodborne illness and Salmonella Mbandaka has also been found to be a contaminant of the layer farm environment. The ability possessed by Salmonella Enteritidis to colonise reproductive organs and contaminate developing eggs has been well described. However, there are few studies investigating this ability for Salmonella Typhimurium. The hypothesis of this study was that the Salmonella Typhimurium can colonise the gut for a prolonged period of time and that horizontal infection through feces is the main route of egg contamination. At 14 weeks of age hens were orally infected with either S. Typhimurium PT 9 or S. Typhimurium PT 9 and Salmonella Mbandaka. Salmonella shedding in feces and eggs was monitored for 15 weeks post infection. Egg shell surface and internal contents of eggs laid by infected hens were cultured independently for detection of Salmonella spp. The mean Salmonella load in feces ranged from 1.54 to 63.35 and 0.31 to 98.38 most probable number/g (MPN/g in the S. Typhimurium and S. Typhimurium + S. Mbandaka group respectively. No correlation was found between mean fecal Salmonella load and frequency of egg shell contamination. Egg shell contamination was higher in S. Typhimurium + S. Mbandaka infected group (7.2% Typhimurium, 14.1% Mbandaka compared to birds infected with S. Typhimurium (5.66% however, co-infection had no significant impact on egg contamination by S. Typhimurium. Throughout the study Salmonella was not recovered from internal contents of eggs laid by hens. Salmonella was isolated from different segments of oviduct of hens from both the groups, however pathology was not observed on microscopic examination. This study investigated Salmonella shedding for up to 15 weeks p.i which is a longer period of

Association between timely initiation of hepatitis B vaccine and completion of the hepatitis B vaccine and national immunization program vaccine series

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Jiang-nan Wu

2016-10-01

Conclusions: Coverage with a timely first dose of HB vaccine is high in children in the community and newborns in hospital, and timely receipt of the first dose of HB vaccine is associated with an increased likelihood of completing the HB vaccine series and the NIPV series in Fujian, China.

Value for money from HPV vaccination and cervical screening

DEFF Research Database (Denmark)

Ashton, Toni; Sopina, Elizaveta (Liza)

2012-01-01

Introduction of human papillomavirus (HPV) vaccination programs raises some important questions about the future organization of cervical screening programs. Two studies - from NZ and Canada - have addressed the question of what combination of vaccination and screening strategies might be most cost......-effective in preventing cervical cancer. Both studies indicate that some modifications to existing screening programs may be desirable as immunized females enter these programs. Variables in HPV vaccination that are likely to be particularly important for determining the future cost-effectiveness of cervical screening...... programs include: vaccine uptake rate, compliance with full doses, timely completion of doses, duration of protection, male vaccination and HPV infection rate. If value for money is to be achieved, it is important that the appropriate data are collected so that policy makers can consider the combined...

Salmonella Typhimurium induces SPI-1 and SPI-2 regulated and strain dependent downregulation of MHC II expression on porcine alveolar macrophages

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Van Parys Alexander

2012-06-01

Full Text Available Abstract Foodborne salmonellosis is one of the most important bacterial zoonotic diseases worldwide. Salmonella Typhimurium is the serovar most frequently isolated from persistently infected slaughter pigs in Europe. Circumvention of the host’s immune system by Salmonella might contribute to persistent infection of pigs. In the present study, we found that Salmonella Typhimurium strain 112910a specifically downregulated MHC II, but not MHC I, expression on porcine alveolar macrophages in a Salmonella pathogenicity island (SPI-1 and SPI-2 dependent way. Salmonella induced downregulation of MHC II expression and intracellular proliferation of Salmonella in macrophages were significantly impaired after opsonization with Salmonella specific antibodies prior to inoculation. Furthermore, the capacity to downregulate MHC II expression on macrophages differed significantly among Salmonella strains, independently of strain specific differences in invasion capacity, Salmonella induced cytotoxicity and altered macrophage activation status. The fact that strain specific differences in MHC II downregulation did not correlate with the extent of in vitro SPI-1 or SPI-2 gene expression indicates that other factors are involved in MHC II downregulation as well. Since Salmonella strain dependent interference with the pig’s immune response through downregulation of MHC II expression might indicate that certain Salmonella strains are more likely to escape serological detection, our findings are of major interest for Salmonella monitoring programs primarily based on serology.

Comparing validation of four ELISAsystems for detection of Salmonella Derby- and Salmonella Infantis-infected pigs

OpenAIRE

Rösler, Uwe; Szabo, Istvan; Matthies, Claudia; Albrecht, Kerstin; Leffler, Kerstin; Scherer, Kathrin; Nöckler, Karsten; Lehmann, Jörg; Methner, Ulrich; Hensel, Andreas

2018-01-01

The objective of this study was the comparative evaluation of four indirect Salmonella ELISA tests at study time approved in Germany to detect Salmonella infection in pigs. Three tests are based on a LPS-antigen mix and directed against specific IgG antibodies. The fourth test is based on a purified S. Typhimurium whole-cell lysate antigen and discriminates between Salmonella-specific IgM-, IgA-, and IgG- antibodies. In a longitudinal study, two groups of six weeks old hybrid piglets were ...

Dynamic Modeling of Cost-effectiveness of Rotavirus Vaccination, Kazakhstan

Science.gov (United States)

Flem, Elmira; Latipov, Renat; Kuatbaeva, Ajnagul; Kristiansen, Ivar Sønbø

2014-01-01

The government of Kazakhstan, a middle-income country in Central Asia, is considering the introduction of rotavirus vaccination into its national immunization program. We performed a cost-effectiveness analysis of rotavirus vaccination spanning 20 years by using a synthesis of dynamic transmission models accounting for herd protection. We found that a vaccination program with 90% coverage would prevent ≈880 rotavirus deaths and save an average of 54,784 life-years for children <5 years of age. Indirect protection accounted for 40% and 60% reduction in severe and mild rotavirus gastroenteritis, respectively. Cost per life year gained was US $18,044 from a societal perspective and US $23,892 from a health care perspective. Comparing the 2 key parameters of cost-effectiveness, mortality rates and vaccine cost at vaccination program costs would be entirely offset. To further evaluate efficacy of a vaccine program, benefits of indirect protection conferred by vaccination warrant further study. PMID:24378188

Vaccination Perceptions of College Students: With and without Vaccination Waiver

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Emmanuel D. Jadhav

2018-02-01

Full Text Available IntroductionThe resurgence of vaccine preventable diseases occurs more often among intentionally unvaccinated individuals, placing at direct risk young adults not caught up on vaccinations. The objectives of this study were to characterize the sociodemographic characteristics of young adults with and without vaccination waivers and identify their perceived benefits, barriers, and influencers of vaccination.MethodsYoung adults (n = 964 from a Midwestern rural university responded to a survey (fall 2015—spring 2016 designed to identify their perception toward vaccination. Instrument consistency was measured using the Cronbach α-scores. The Chi-square test was used to test any sociodemographic differences and Mann–Whitney U-tests results for differences between exempt and non-exempt students. Analysis occurred in spring 2017.ResultsA little over one-third of young adults with a vaccination waiver were not up to date on their vaccinations, and think that vaccinations can cause autism. The biggest identifiable benefit was effective control against disease. The surveyed young adults ranked the out of pocket cost associated with vaccination as the most important barrier and safe and easy to use vaccines as the most important influencer of vaccination.ConclusionYoung adults who have had a vaccination waiver appear to not be up to date on their vaccinations. Vaccine administration programs, such as university campus clinics, would benefit from addressing perceptions unique to young adults with and without a vaccine waiver. This would subsequently better provide young adults a second shot for getting appropriately caught up on vaccinations.

Prevalence and antibiotic resistance of Salmonella Enteritidis and Salmonella Typhimurium in raw chicken meat at retail markets in Malaysia.

Science.gov (United States)

Thung, T Y; Mahyudin, N A; Basri, D F; Wan Mohamed Radzi, C W J; Nakaguchi, Y; Nishibuchi, M; Radu, S

2016-08-01

Salmonellosis is one of the major food-borne diseases in many countries. This study was carried out to determine the occurrence of Salmonella spp., Salmonella Enteritidis, and Salmonella Typhimurium in raw chicken meat from wet markets and hypermarkets in Selangor, as well as to determine the antibiotic susceptibility profile of S. Enteritidis and S. Typhimurium. The most probable number (MPN) in combination with multiplex polymerase chain reaction (mPCR) method was used to quantify the Salmonella spp., S. Enteritidis, and S. Typhimurium in the samples. The occurrence of Salmonella spp., S. Enteritidis, and S. Typhimurium in 120 chicken meat samples were 20.80%, 6.70%, and 2.50%, respectively with estimated quantity varying from retail chicken meat could be a source of multiple antimicrobial-resistance Salmonella and may constitute a public health concern in Malaysia. © 2016 Poultry Science Association Inc.

Salmonella-secreted Virulence Factors

Energy Technology Data Exchange (ETDEWEB)

Heffron, Fred; Niemann, George; Yoon, Hyunjin; Kidwai, Afshan S.; Brown, Roslyn N.; McDermott, Jason E.; Smith, Richard D.; Adkins, Joshua N.

2011-05-01

In this short review we discuss secreted virulence factors of Salmonella, which directly affect Salmonella interaction with its host. Salmonella secretes protein to subvert host defenses but also, as discussed, to reduce virulence thereby permitting the bacteria to persist longer and more successfully disperse. The type III secretion system (TTSS) is the best known and well studied of the mechanisms that enable secretion from the bacterial cytoplasm to the host cell cytoplasm. Other secretion systems include outer membrane vesicles, which are present in all Gram-negative bacteria examined to date, two-partner secretion, and type VI secretion will also be addressed. Excellent reviews of Salmonella secreted effectors have focused on themes such as actin rearrangements, vesicular trafficking, ubiquitination, and the activities of the virulence factors themselves. This short review is based on S. Typhimurium infection of mice because it is a model of typhoid like disease in humans. We have organized effectors in terms of events that happen during the infection cycle and how secreted effectors may be involved.

Non-Typhoidal Salmonella Aortitis in a transplant patient

International Nuclear Information System (INIS)

Tarif, N.; Azam, M.N.; Mitwalli, Ahmad H.; Al-Wakeel, Jamal S.; El-Kheder, A. Al-Aboud

2002-01-01

Non-typhoidal salmonella bacteremia may result in extra gastrointestinallocalization of infection. Aortitis due to non-typhoidal salmonella wasreported to be the cause of 38-42% of all infected abdominal aortitis.Underlying atherosclerosis is a frequent site for salmonella aortitis. Wedescribe here a case of possible salmonella aortitis in a renal transplantpatient. (author)

Test results of Salmonella typing by the National Reference Laboratories for Salmonella in the Member States of the European Union and the EnterNet Laboratories - Collaborative study VII on typing of Salmonella

NARCIS (Netherlands)

Korver H; Maas HME; Ward LR; Wannet WJB; Henken AM; MGB; LIS

2003-01-01

Het Communautair Referentie Laboratorium voor Salmonella (CRL-Salmonella, Bilthoven, Nederland) organiseerde in samenwerking met Public Health Laboratory Services (PHLS), London, Verenigd Koninkrijk een zevende ringonderzoek aangaande de typering van Salmonella. Zeventien Nationale Referentie

Serologic reactions against Salmonella in samples from broiler parent stock with and without preceding colibacillosis: A case-control study

DEFF Research Database (Denmark)

Gradel, K.O.; Feld, Niels Christian; Andersen, J. S.

2001-01-01

In the Danish Salmonella Control Program, eggs from broiler parent flocks are surveyed by serologic analysis every 4 wk for antibodies against Salmonella lipopolysaccharide O-antigens 1, 4, 5, 9, and 12 (Mix-enzyme-linked immunosorbent assay [ELISA]) and 6 and 7 (Infantis-ELISA). The antibody...... response is measured in percentage optical density (OD%) of a strong positive reaction, and the cutoff value has been determined to be 40 OD%. Two or more reactors above 40 OD% will place the parent flock under suspicion. There has been concern about possible cross-reactions between Salmonella spp....... and other Enterobacteriaceae, e.g., Escherichia coli, because a high specificity of a Salmonella antibody test is desirable. Moreover, false-positive Salmonella results have economic consequences and impede planning the production. A case-control study based on cases of clinical E. coli infections...

A carbon nanotube immunosensor for Salmonella

Science.gov (United States)

Lerner, Mitchell B.; Goldsmith, Brett R.; McMillon, Ronald; Dailey, Jennifer; Pillai, Shreekumar; Singh, Shree R.; Johnson, A. T. Charlie

2011-12-01

Antibody-functionalized carbon nanotube devices have been suggested for use as bacterial detectors for monitoring of food purity in transit from the farm to the kitchen. Here we report progress towards that goal by demonstrating specific detection of Salmonella in complex nutrient broth solutions using nanotube transistors functionalized with covalently-bound anti-Salmonella antibodies. The small size of the active device region makes them compatible with integration in large-scale arrays. We find that the on-state current of the transistor is sensitive specifically to the Salmonella concentration and saturates at low concentration (Salmonella and other bacteria types, with no sign of saturation even at much larger concentrations (108 cfu/ml).

Human papillomavirus vaccine motivators and barriers among community college students: Considerations for development of a successful vaccination program.

Science.gov (United States)

Hirth, Jacqueline M; Batuuka, Denise N; Gross, Tyra T; Cofie, Leslie; Berenson, Abbey B

2018-02-14

Previous interventions in colleges to improve human papillomavirus (HPV) vaccination have not been highly successful. Although barriers have been assessed in traditional colleges, less is known about vaccination barriers in community colleges. We approached students aged 18-26 years old enrolled at a community college for an in-person semi-structured qualitative interview on HPV vaccination and health, with questions guided by the Theory of Planned Behavior. Data collection took place between April 2015 and December 2015. Thematic analysis techniques were used to analyze the data. During interviews with 19 students, 4 themes emerged, including: general vaccine attitudes, barriers to HPV vaccination, motivators to HPV vaccination, and social influences. Participants felt that vaccines were beneficial, but were concerned about side effects. They felt that getting the HPV vaccine would be inconvenient, and they did not know enough about it to decide. Most would not trust their friends' opinions, but would want to know about side effects that their vaccinated friends experienced. Successful interventions at community colleges should include several components to increase convenience as well as utilize interactive methods to promote HPV vaccine awareness. Copyright © 2018. Published by Elsevier Ltd.

The Impact of Making Vaccines Thermostable in Niger’s Vaccine Supply Chain

Science.gov (United States)

Lee, Bruce Y.; Cakouros, Brigid E.; Assi, Tina-Marie; Connor, Diana L.; Welling, Joel; Kone, Souleymane; Djibo, Ali; Wateska, Angela R.; Pierre, Lionel; Brown, Shawn T.

2012-01-01

Objective Determine the effects on the vaccine cold chain of making different types of World Health Organization (WHO) Expanded Program on Immunizations (EPI) vaccines thermostable. Methods Utilizing a detailed computational, discrete-event simulation model of the Niger vaccine supply chain, we simulated the impact of making different combinations of the six current EPI vaccines thermostable. Findings Making any EPI vaccine thermostable relieved existing supply chain bottlenecks (especially at the lowest levels), increased vaccine availability of all EPI vaccines, and decreased cold storage and transport capacity utilization. By far, the most substantial impact came from making the pentavalent vaccine thermostable, increasing its own vaccine availability from 87% to 97% and the vaccine availabilities of all other remaining non-thermostable EPI vaccines to over 93%. By contrast, making each of the other vaccines thermostable had considerably less effect on the remaining vaccines, failing to increase the vaccine availabilities of other vaccines to more than 89%. Making tetanus toxoid vaccine along with the pentavalent thermostable further increased the vaccine availability of all EPI vaccines by at least 1–2%. Conclusion Our study shows the potential benefits of making any of Niger’s EPI vaccines thermostable and therefore supports further development of thermostable vaccines. Eliminating the need for refrigerators and freezers should not necessarily be the only benefit and goal of vaccine thermostability. Rather, making even a single vaccine (or some subset of the vaccines) thermostable could free up significant cold storage space for other vaccines, and thereby help alleviate supply chain bottlenecks that occur throughout the world. PMID:22789507

The Salmonella enterica Pan-genome

DEFF Research Database (Denmark)

Jacobsen, Annika; Hendriksen, Rene S.; Aarestrup, Frank Møller

2011-01-01

Salmonella enterica is divided into four subspecies containing a large number of different serovars, several of which are important zoonotic pathogens and some show a high degree of host specificity or host preference. We compare 45 sequenced S. enterica genomes that are publicly available (22......, and the core and pan-genome of Salmonella were estimated to be around 2,800 and 10,000 gene families, respectively. The constructed pan-genomic dendrograms suggest that gene content is often, but not uniformly correlated to serotype. Any given Salmonella strain has a large stable core, whilst...... there is an abundance of accessory genes, including the Salmonella pathogenicity islands (SPIs), transposable elements, phages, and plasmid DNA. We visualize conservation in the genomes in relation to chromosomal location and DNA structural features and find that variation in gene content is localized in a selection...

Monitoring what governments "give for" and "spend on" vaccine procurement: Vaccine Procurement Assistance and Vaccine Procurement Baseline.

Science.gov (United States)

Nelson, E A S; Bloom, David E; Mahoney, Richard T

2014-01-01

The Global Vaccine Action Plan will require, inter alia, the mobilization of financial resources from donors and national governments - both rich and poor. Vaccine Procurement Assistance (VPA) and Vaccine Procurement Baseline (VPB) are two metrics that could measure government performance and track resources in this arena. VPA is proposed as a new subcategory of Official Development Assistance (ODA) given for the procurement of vaccines and VPB is a previously suggested measure of the share of Gross Domestic Product (GDP) that governments spend on their own vaccine procurement. To determine realistic targets for VPA and VPB. Organization for Economic Co-Operation and Development (OECD) and World Bank data for 2009 were analyzed to determine the proportions of bilateral ODA from the 23 Development Assistance Committee (DAC) countries disbursed (as % of GDP in current US$) for infectious disease control. DAC country contributions to the GAVI Alliance for 2009 were assessed as a measure of multilateral donor support for vaccines and immunization programs. In 2009, total DAC bilateral ODA was 0.16% of global GDP and 0.25% of DAC GDP. As a percentage of GDP, Norway (0.013%) and United Kingdom (0.0085%) disbursed the greatest proportion of bilateral ODA for infectious disease control, and Norway (0.024%) and Canada (0.008%) made the greatest contributions to the GAVI Alliance. In 2009 0.02% of DAC GDP was US$7.61 billion and 0.02% of the GDP of the poorest 117 countries was US$2.88 billion. Adopting 0.02% GDP as minimum targets for both VPA and VPB is based on realistic estimates of what both developed and developing countries should spend, and can afford to spend, to jointly ensure procurement of vaccines recommended by national and global bodies. New OECD purpose codes are needed to specifically track ODA disbursed for a) vaccine procurement; and b) immunization programs.

Changing Attitudes Toward Influenza Vaccination in U.S. Kidney Transplant Programs Over the Past Decade

OpenAIRE

Chon, W. James; Kadambi, Pradeep V.; Harland, Robert C.; Thistlethwaite, J. Richard; West, Bradford L.; Udani, Suneel; Poduval, Rajiv; Josephson, Michelle A.

2010-01-01

Background and objectives: Influenza infection in transplant recipients is often associated with significant morbidity. Surveys were conducted in 1999 and 2009 to find out if the influenza vaccination practices in the U.S. transplant programs had changed over the past 10 years.

Phenotypic and molecular characterization of Salmonella serotypes ...

African Journals Online (AJOL)

The presence of Salmonella and human pathogens in unpasteurized milk remains a public health hazard. The study reported the phenotypic and molecular characterization of Salmonella serotypes in cow raw milk, cheese and traditional yoghurt marketed for man's consumption in Nigeria. Isolation of Salmonella was done ...

A defective mutant of Salmonella enterica Serovar Gallinarum in cobalamin biosynthesis is avirulent in chickens Mutante de Salmonella enterica serovar Gallinarum duplo defectivo na biossíntese de cobalamina é avirulento para aves

Directory of Open Access Journals (Sweden)

Jacqueline Boldrin de Paiva

2009-09-01

Full Text Available Salmonella enterica serovar Gallinarum (SG is a fowl typhoid agent in chickens and is a severe disease with worldwide economic impact as its mortality may reach up to 80%. It is one of a small group of serovars that typically produces typhoid-like infections in a narrow range of host species and which therefore represents a good model for human typhoid. The survival mechanisms are not considered to be virulent mechanisms but are essential for the life of the bacterium. Mutants of Salmonella Gallinarum containing defective genes, related to cobalamin biosynthesis and which Salmonella spp. has to be produced to survive when it is in an anaerobic environment, were produced in this study. Salmonella Gallinarum is an intracellular parasite. Therefore, this study could provide information about whether vitamin B12 biosynthesis might be essential to its survival in the host. The results showed that the singular deletion in cbiA or cobS genes did not interfere in the life of Salmonella Gallinarum in the host, perhaps because single deletion is not enough to impede vitamin B12 biosynthesis. It was noticed that diluted SG mutants with single deletion produced higher mortality than the wild strain of SG. When double mutation was carried out, the Salmonella Gallinarum mutant was unable to provoke mortality in susceptible chickens. This work showed that B12 biosynthesis is a very important step in the metabolism of Salmonella Gallinarum during the infection of the chickens. Further research on bacterium physiology should be carried out to elucidate the events described in this research and to assess the mutant as a vaccine strain.Salmonella enterica serovar Gallinarum (SG é o agente do tifo aviário, doença severa que provoca mortalidade em até 80% do plantel de aves. SG encontra-se entre os poucos sorotipos de Salmonella que são agentes etiológicos de enfermidade específica, à semelhança de Salmonella Typhi em seres humanos podendo, portanto, servir

Experimental investigations into the effects of irradiation with neutron and gamma rays on the immune system, as demonstrated at the model of immunity of Salmonella typhimurium on the mouse

International Nuclear Information System (INIS)

Hahn, H.

1985-01-01

Mice were irradiated with neutron and gamma rays (with a dose of 200 rad respectively 300 rad). Either 24 hours before or after the irradiation the mice were vaccinated and revaccinated with a Salmonella typhimurium vaccine. By ELISA, IHA and BTZD-test specific antibodies against Salmonella typhimurium could be found. The 200 rad irradiated animals had a lower increase in the formation of antibodies compared with mice not irradiated, if the irradiation was applied before the immunisation. On the 300 rad irradiated animals a reduction of the formation of the antibodies could be observed, too. The antibody titres, however, were higher and an earlier increase of the number of the antibodies was found in comparison with the 200 rad irradiated animals. A second antigene application after 7 days and an irradiation after the first respectively the second immunisation gave no noticeable proof of immune suppression. In our tests it was found out, that for the definition of the antibody titres of the sera the ELISA and the IHA had been more sensitive than the BTZD-test. (orig./MG) [de

Making Common Sense of Vaccines: An Example of Discussing the Recombinant Attenuated Salmonella Vaccine with the Public.

Science.gov (United States)

Dankel, Dorothy J; Roland, Kenneth L; Fisher, Michael; Brenneman, Karen; Delgado, Ana; Santander, Javier; Baek, Chang-Ho; Clark-Curtiss, Josephine; Strand, Roger; Curtiss, Roy

2014-01-01

Researchers have iterated that the future of synthetic biology and biotechnology lies in novel consumer applications of crossing biology with engineering. However, if the new biology's future is to be sustainable, early and serious efforts must be made towards social sustainability. Therefore, the crux of new applications of synthetic biology and biotechnology is public understanding and acceptance. The RASVaccine is a novel recombinant design not found in nature that re-engineers a common bacteria ( Salmonella ) to produce a strong immune response in humans. Synthesis of the RASVaccine has the potential to improve public health as an inexpensive, non-injectable product. But how can scientists move forward to create a dialogue of creating a 'common sense' of this new technology in order to promote social sustainability? This paper delves into public issues raised around these novel technologies and uses the RASVaccine as an example of meeting the public with a common sense of its possibilities and limitations.

Assessing the Potential Cost-Effectiveness of Microneedle Patches in Childhood Measles Vaccination Programs: The Case for Further Research and Development.

Science.gov (United States)

Adhikari, Bishwa B; Goodson, James L; Chu, Susan Y; Rota, Paul A; Meltzer, Martin I

2016-12-01

Currently available measles vaccines are administered by subcutaneous injections and require reconstitution with a diluent and a cold chain, which is resource intensive and challenging to maintain. To overcome these challenges and potentially increase vaccination coverage, microneedle patches are being developed to deliver the measles vaccine. This study compares the cost-effectiveness of using microneedle patches with traditional vaccine delivery by syringe-and-needle (subcutaneous vaccination) in children's measles vaccination programs. We built a simple spreadsheet model to compute the vaccination costs for using microneedle patch and syringe-and-needle technologies. We assumed that microneedle vaccines will be, compared with current vaccines, more heat stable and require less expensive cool chains when used in the field. We used historical data on the incidence of measles among communities with low measles vaccination rates. The cost of microneedle vaccination was estimated at US$0.95 (range US$0.71-US$1.18) for the first dose, compared with US$1.65 (range US$1.24-US$2.06) for the first dose delivered by subcutaneous vaccination. At 95 % vaccination coverage, microneedle patch vaccination was estimated to cost US$1.66 per measles case averted (range US$1.24-US$2.07) compared with an estimated cost of US$2.64 per case averted (range US$1.98-US$3.30) using subcutaneous vaccination. Use of microneedle patches may reduce costs; however, the cost-effectiveness of patches would depend on the vaccine recipients' acceptability and vaccine effectiveness of the patches relative to the existing conventional vaccine-delivery method. This study emphasizes the need to continue research and development of this vaccine-delivery method that could boost measles elimination efforts through improved access to vaccines and increased vaccination coverage.

Decreased management of genital warts in young women in Australian general practice post introduction of national HPV vaccination program: results from a nationally representative cross-sectional general practice study.

Directory of Open Access Journals (Sweden)

Christopher Harrison

Full Text Available OBJECTIVES: Since the introduction of Australia's human papillomavirus vaccination program, the management rate of genital warts in sexual health clinics and private hospitals has decreased in women of vaccine-eligible age. However, most genital warts in Australia are managed in general practice. This study examines whether a similar decrease occurred in Australian general practice after the introduction of the program. METHODS: Analysis of a nationally representative cross-sectional database of Australian general practice activity (1,175,879 patient encounters with 11,780 general practitioners. Genital warts management rates were estimated for the periods before and after introduction of the program (Pre-program, July 2002-June 2006; Post-program, July 2008-June 2012. Control conditions included genital herpes and gardnerella/bacterial vaginosis in female patients and genital herpes and urethritis in male patients. Trends in management rates by year, pre-vaccine (July 2000-June 2007 and post-vaccine (July 2007-June 2012 were also calculated. RESULTS: Management rate of genital warts among women potentially covered by program (aged 15-27 years decreased by 61% from 4.33 per 1,000 encounters in the Pre-program period to 1.67 in the Post-program period. Trend analysis of the post-vaccine period showed, among women of vaccine eligible age, a significant year-on-year reduction in the rate of genital warts management (p<0.0001 and a significant increase in the management rate of control conditions per year (p<0.0001. For all other age-sex groups there was no significant change in the management rate of genital warts between the Pre- and Post-program periods. CONCLUSION: The large decrease in general practice management of genital warts in women of vaccine-eligible age highlights the success of the program in the wider community.

Detoxification of Salmonella typhimurium lipopolysaccharide by ionizing radiation.

Science.gov (United States)

Previte, J J; Chang, Y; el-Bisi, H M

1967-05-01

The efficiency of ionizing radiation in detoxifying the lethal determinant(s) of the lipopolysaccharide (LPS) of Salmonella typhimurium, S. enteritidis, and Escherichia coli in aqueous solution and associated with heat-killed S. typhimurium cells in suspension decreased with doses above 1 Mrad. The 50% end point of inactivation was more than 7.0 Mrad for heat-killed salmonellae and 4.8, 4.5, and 1.0 Mrad for the LPS of S. typhimurium, S. enteritidis, and E. coli, respectively. After exposure to 20 Mrad, S. typhimurium LPS retained a small portion of its lethal properties although the ld(50) was much greater than 9.5 mg per 20-g mouse. However, at -184 C, no inactivation of the lethal determinant(s) occurred after exposure to as much as 20 Mrad. This demonstrated the significance of the indirect effect and the mobility and formation of free radicals. At 22 C, the optical density at 400 mmu increased and the pH decreased with increasing radiation dose, but no qualitative changes were observed in the infrared spectrum. No change was observed in the pyrogenicity of S. typhimurium LPS; a slight decrease in antigenicity was revealed when 6 days, but not when 1 day, elapsed between vaccination and challenge in the mouse protection test. The results were interpreted as evidence of the existence of two or more lethal and antigenic determinants. The differential effect of radiation on these properties and on the pyrogenic component(s) probably are indicative of separate functional sites for lethal, antigenic, and pyrogenic activities.

Tentative Colistin Epidemiological Cut-Off Value for Salmonella spp

DEFF Research Database (Denmark)

Agersø, Yvonne; Torpdahl, Mia; Zachariasen, Camilla

2012-01-01

. Interestingly, Salmonella Dublin and Salmonella Enteritidis belong to the same O-group (O:1, 9,12), suggesting that surface lipopolysaccharides (LPS) of the cell (O-antigen) play a role in colistin susceptibility. The epidemiological cut-off value of >2 mg/L for colistin suggested by European Committee...... on Antimicrobial Susceptibility Testing (EUCAST) is placed inside the distribution for both Salmonella Dublin and Salmonella Enteritidis. All tested Salmonella Dublin isolates, regardless of MIC colistin value, had identical pmrA and pmrB sequences. Missense mutations were found only in pmrA in one Salmonella...

A single-tube screen for Salmonella and Shigella.

Science.gov (United States)

Procop, Gary W; Wallace, Jacqueline D; Tuohy, Marion J; Lasalvia, Margret M; Addison, Rachel M; Reller, L Barth

2008-08-01

Salmonella and Shigella species are routinely sought in stool specimens submitted for culture. It is a common practice to screen lactose-negative colonies by using triple sugar iron agar, lysine iron agar, and Christensen urea agar to determine if further identification is necessary. We designed and evaluated a novel combination of media, which are layered in a single tube, for screening isolates suspected to possibly represent Salmonella or Shigella. We tested this media combination with 106 Salmonella, 56 Shigella, and 56 other gram-negative bacilli. All Salmonella and Shigella isolates tested were appropriately characterized as possible Salmonella or Shigella by using an algorithm developed for use with this media combination. Similarly, 53 (95%) of 56 other gram-negative bacilli were appropriately screened as non -Salmonella and non -Shigella isolates. This unique media combination provides the most important biochemical reactions needed to screen for Salmonella and Shigella in a single-tube format, which decreases labor by two thirds (ie, 1 tube is inoculated vs 3).

Evaluation of the Thermo Scientific™ SureTect™ Salmonella species Assay.

Science.gov (United States)

Cloke, Jonathan; Clark, Dorn; Radcliff, Roy; Leon-Velarde, Carlos; Larson, Nathan; Dave, Keron; Evans, Katharine; Crabtree, David; Hughes, Annette; Simpson, Helen; Holopainen, Jani; Wickstrand, Nina; Kauppinen, Mikko

2014-03-01

The Thermo Scientific™ SureTect™ Salmonella species Assay is a new real-time PCR assay for the detection of Salmonellae in food and environmental samples. This validation study was conducted using the AOAC Research Institute (RI) Performance Tested MethodsSM program to validate the SureTect Salmonella species Assay in comparison to the reference method detailed in International Organization for Standardization 6579:2002 in a variety of food matrixes, namely, raw ground beef, raw chicken breast, raw ground pork, fresh bagged lettuce, pork frankfurters, nonfat dried milk powder, cooked peeled shrimp, pasteurized liquid whole egg, ready-to-eat meal containing beef, and stainless steel surface samples. With the exception of liquid whole egg and fresh bagged lettuce, which were tested in-house, all matrixes were tested by Marshfield Food Safety, Marshfield, WI, on behalf of Thermo Fisher Scientific. In addition, three matrixes (pork frankfurters, lettuce, and stainless steel surface samples) were analyzed independently as part of the AOAC-RI-controlled laboratory study by the University of Guelph, Canada. No significant difference by probability of detection or McNemars Chi-squared statistical analysis was found between the candidate or reference methods for any of the food matrixes or environmental surface samples tested during the validation study. Inclusivity and exclusivity testing was conducted with 117 and 36 isolates, respectively, which demonstrated that the SureTect Salmonella species Assay was able to detect all the major groups of Salmonella enterica subspecies enterica (e.g., Typhimurium) and the less common subspecies of S. enterica (e.g., arizoniae) and the rarely encountered S. bongori. None of the exclusivity isolates analyzed were detected by the SureTect Salmonella species Assay. Ruggedness testing was conducted to evaluate the performance of the assay with specific method deviations outside of the recommended parameters open to variation

The Typhoid Fever Surveillance in Africa Program (TSAP): Clinical, Diagnostic, and Epidemiological Methodologies.

Science.gov (United States)

von Kalckreuth, Vera; Konings, Frank; Aaby, Peter; Adu-Sarkodie, Yaw; Ali, Mohammad; Aseffa, Abraham; Baker, Stephen; Breiman, Robert F; Bjerregaard-Andersen, Morten; Clemens, John D; Crump, John A; Cruz Espinoza, Ligia Maria; Deerin, Jessica Fung; Gasmelseed, Nagla; Sow, Amy Gassama; Im, Justin; Keddy, Karen H; Cosmas, Leonard; May, Jürgen; Meyer, Christian G; Mintz, Eric D; Montgomery, Joel M; Olack, Beatrice; Pak, Gi Deok; Panzner, Ursula; Park, Se Eun; Rakotozandrindrainy, Raphaël; Schütt-Gerowitt, Heidi; Soura, Abdramane Bassiahi; Warren, Michelle R; Wierzba, Thomas F; Marks, Florian

2016-03-15

New immunization programs are dependent on data from surveillance networks and disease burden estimates to prioritize target areas and risk groups. Data regarding invasive Salmonella disease in sub-Saharan Africa are currently limited, thus hindering the implementation of preventive measures. The Typhoid Fever Surveillance in Africa Program (TSAP) was established by the International Vaccine Institute to obtain comparable incidence data on typhoid fever and invasive nontyphoidal Salmonella (iNTS) disease in sub-Saharan Africa through standardized surveillance in multiple countries. Standardized procedures were developed and deployed across sites for study site selection, patient enrolment, laboratory procedures, quality control and quality assurance, assessment of healthcare utilization and incidence calculations. Passive surveillance for bloodstream infections among febrile patients was initiated at thirteen sentinel sites in ten countries (Burkina Faso, Ethiopia, Ghana, Guinea-Bissau, Kenya, Madagascar, Senegal, South Africa, Sudan, and Tanzania). Each TSAP site conducted case detection using these standardized methods to isolate and identify aerobic bacteria from the bloodstream of febrile patients. Healthcare utilization surveys were conducted to adjust population denominators in incidence calculations for differing healthcare utilization patterns and improve comparability of incidence rates across sites. By providing standardized data on the incidence of typhoid fever and iNTS disease in sub-Saharan Africa, TSAP will provide vital input for targeted typhoid fever prevention programs. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Employee influenza vaccination in residential care facilities.

Science.gov (United States)

Apenteng, Bettye A; Opoku, Samuel T

2014-03-01

The organizational literature on infection control in residential care facilities is limited. Using a nationally representative dataset, we examined the organizational factors associated with implementing at least 1 influenza-related employee vaccination policy/program, as well as the effect of vaccination policies on health care worker (HCW) influenza vaccine uptake in residential care facilities. The study was a cross-sectional study using data from the 2010 National Survey of Residential Care Facilities. Multivariate logistic regression analysis was used to address the study's objectives. Facility size, director's educational attainment, and having a written influenza pandemic preparedness plan were significantly associated with the implementation of at least 1 influenza-related employee vaccination policy/program, after controlling for other facility-level factors. Recommending vaccination to employees, providing vaccination on site, providing vaccinations to employees at no cost, and requiring vaccination as a condition of employment were associated with higher employee influenza vaccination rates. Residential care facilities can improve vaccination rates among employees by adopting effective employee vaccination policies. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

Implementation of a hepatitis A/B vaccination program using an accelerated schedule among high-risk inmates, Los Angeles County Jail, 2007-2010.