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Sample records for avian infection plagued

  1. Plague

    Science.gov (United States)

    Abbott, Rachel C.; Rocke, Tonie E.

    2012-01-01

    Plague offers readers an overview of this highly complex disease caused by the bacteria Yersinia pestis. The history of the disease, as well as information about Yersinia pestis and its transmission by fleas, is described. The section Geographic Distribution presents areas of the world and United States where plague occurs most commonly in rodents and humans. Species Susceptibility describes infection and disease rates in rodents, humans, and other animals. Disease Ecology considers the complex relationship among rodents, domestic and wild animals, and humans and explores possible routes of transmission and maintenance of the organism in the environment. The effects of climate change, the potential for Y. pestis to be used as a bioweapon, and the impact of plague on conservation of wildlife are considered in Points to Ponder. Disease Prevention and Control outlines methods of prevention and treatment including vaccination for prairie dogs and black-footed ferrets. A glossary of technical terms is included. Tonie E. Rocke, the senior author and an epizootiologist at the USGS National Wildlife Health Center (NWHC), is a prominent researcher on oral vaccination of prairie dogs to prevent plague. She is currently working to transfer her success in the laboratory to the field to control plague in prairie dogs. Rachel C. Abbott, a biologist at the NWHC, is assisting Dr. Rocke in this process and will coordinate field trials of the vaccine. Milt Friend, first director of the NWHC, wrote the foreword. Plague is intended for scholars and the general public. The material is presented in a simple, straightforward manner that serves both audiences. Numerous illustrations and tables provide easily understood summaries of key points and information.

  2. Plague

    Science.gov (United States)

    ... In the Middle Ages in Europe, massive plague epidemics killed millions of people. Plague has not been eliminated. It can still be found in Africa, Asia, and South America. Today, plague is rare in the United States. ...

  3. Ecology of plague in Africa: response of indigenous wild rodents to experimental plague infection

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    Isaäcson, Margaretha; Taylor, Paul; Arntzen, Lorraine

    1983-01-01

    The Mastomys natalensis species complex, subdivided into genetically distinct species having diploid chromosome numbers 2n = 32 and 2n = 36, is a reservoir for several zoonoses including Lassa fever and plague. This report describes a study to determine whether these sibling species and three other rodent species have different potential as reservoirs for plague. It was found that M. natalensis (2n = 32) was significantly more resistant to experimental plague infection (50% survived inoculati...

  4. Ecology of plague in Africa: response of indigenous wild rodents to experimental plague infection.

    Science.gov (United States)

    Isaäcson, M; Taylor, P; Arntzen, L

    1983-01-01

    The Mastomys natalensis species complex, subdivided into genetically distinct species having diploid chromosome numbers 2n = 32 and 2n = 36, is a reservoir for several zoonoses including Lassa fever and plague. This report describes a study to determine whether these sibling species and three other rodent species have different potential as reservoirs for plague. It was found that M. natalensis (2n = 32) was significantly more resistant to experimental plague infection (50% survived inoculation with 120 000 Yersinia pseudotuberculosis subsp. pestis) than was M. coucha (2n = 36) (none of which survived doses of 190 Y. pseudotuberculosis subsp.pestis). In descending order of resistance were M. natalensis, Aethomys chrysophilus, M. coucha, Tatera leucogaster and A. namaquensis. No A. namaquensis survived inoculation of 10 or more plague bacilli.Previous reports on susceptibility to plague or other infections, which were based exclusively on findings in the universally distributed laboratory-bred Mastomys, are thus not necessarily applicable to the M. natalensis species as a whole but probably only to M. coucha. The Y. pseudotuberculosis subsp. pestis fraction-1 passive haemagglutination test appeared to be relatively insensitive in that only 5 out of 47 animals surviving experimental plague infection showed specific antibodies 6 weeks after challenge.The geographic distribution of human plague in southern Africa corresponds closely with that of the plague-susceptible species, M. coucha, while the resistant species, M. natalensis, predominates in areas where human plague has not been recorded. The role of A. namaquensis in the ecology of plague needs to be carefully studied and its possible importance in plague research should be investigated further.

  5. Susceptibility to Yersinia pestis experimental infection in wild Rattus rattus, reservoir of plague in Madagascar

    OpenAIRE

    Tollenaere, C., Pernechele, B., Mäkinen, H., Parratt, S., Nemeth, M., Kovacs, G., Levente, K. Tack, A.; Rahalison, L.; Ranjalahy, M.; Duplantier, Jean-Marc; Rahelinirina, S.; Telfer, S.; Brouat, Carine

    2010-01-01

    In Madagascar, the black rat, Rattus rattus, is the main reservoir of plague (Yersinia pestis infection), a disease still responsible for hundreds of cases each year in this country. This study used experimental plague challenge to assess susceptibility in wild-caught rats to better understand how R. rattus can act as a plague reservoir. An important difference in plague resistance between rat populations from the plague focus (central highlands) and those from the plague-free zone (low altit...

  6. Plague: Infections of Companion Animals and Opportunities for Intervention

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    Petra C.F. Oyston

    2011-06-01

    Full Text Available Plague is a zoonotic disease, normally circulating in rodent populations, transmitted to humans most commonly through the bite of an infected flea vector. Secondary infection of the lungs results in generation of infectious aerosols, which pose a significant hazard to close contacts. In enzootic areas, plague infections have been reported in owners and veterinarians who come into contact with infected pets. Dogs are relatively resistant, but can import infected fleas into the home. Cats are acutely susceptible, and can present a direct hazard to health. Reducing roaming and hunting behaviours, combined with flea control measures go some way to reducing the risk to humans. Various vaccine formulations have been developed which may be suitable to protect companion animals from contracting plague, and thus preventing onward transmission to man. Since transmission has resulted in a number of fatal cases of plague, the vaccination of domestic animals such as cats would seem a low cost strategy for reducing the risk of infection by this serious disease in enzootic regions.

  7. Plague

    Science.gov (United States)

    ... is a disease that affects humans and other mammals. People typically get infected after being bitten by ... Facilities Biosafety Laboratory Sites Rutgers University University of Alabama George Mason University Tufts University Tulane University Regional ...

  8. Avian Influenza infection in Human

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    Mohan. M

    2008-08-01

    Full Text Available Outbreaks caused by the H5N1 strain are presently of the greatest concern for human health. In assessing risks to human health, it is important to know exactly which avian virus strains are causing the outbreaks in birds.All available evidence points to an increased risk of transmission to humans when outbreaks of highly pathogenic avian H5N1 influenza are widespread in poultry. There is mounting evidence that this strain has a unique capacity to jump the species barrier and cause severe disease, with high mortality, in humans. There is no evidence, to date that efficient human to human transmission of H5N1 strain has occurred and very often. Efficient transmission among humans is a key property of pandemic strains and a property that the avian H5N1 and H9N2 viruses apparently lacked. The biological and molecular basis for effective aerosol transmission among humans is not known. The virus can improve its transmissibility among humans via two principal mechanisms. The first is a “reassortment” event, in which genetic material is exchanged between human and avian viruses during co-infection of a human or pig.Reassortment could result in a fully transmissible pandemic virus, announced by a sudden surge of cases with explosive spread. The second mechanism is a more gradual process of adaptive mutation, whereby the capability of the virus to bind to human cells increases during subsequent infections of humans. Adaptive mutation, expressed initially as small clusters of human cases with some evidence of human-to-human transmission, would probably give the world some time to take defensive action, if detected sufficiently early. As the number of human infections grows, the risk increases that a new virus subtype could emerge, triggering an influenza pandemic. Humans as well as swine must now be considered a potential mixing vessel for the generation of such a virus. This link between widespread infection in poultry and increased risk of human

  9. Susceptibility to Yersinia pestis experimental infection in wild Rattus rattus, reservoir of plague in Madagascar.

    Science.gov (United States)

    Tollenaere, C; Rahalison, L; Ranjalahy, M; Duplantier, J-M; Rahelinirina, S; Telfer, S; Brouat, C

    2010-06-01

    In Madagascar, the black rat, Rattus rattus, is the main reservoir of plague (Yersinia pestis infection), a disease still responsible for hundreds of cases each year in this country. This study used experimental plague challenge to assess susceptibility in wild-caught rats to better understand how R. rattus can act as a plague reservoir. An important difference in plague resistance between rat populations from the plague focus (central highlands) and those from the plague-free zone (low altitude area) was confirmed to be a widespread phenomenon. In rats from the plague focus, we observed that sex influenced plague susceptibility, with males slightly more resistant than females. Other individual factors investigated (weight and habitat of sampling) did not affect plague resistance. When infected at high bacterial dose (more than 10⁵ bacteria injected), rats from the plague focus died mainly within 3-5 days and produced specific antibodies, whereas after low-dose infection (plague resistance level and the course of infection in the black rat would contribute to a better understanding of plague circulation in Madagascar.

  10. Avian Influenza A Virus Infections in Humans

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    ... their saliva, mucous and feces. Human infections with bird flu viruses can happen when enough virus gets into ... Virus (CVV) for a Highly Pathogenic Avian Influenza (Bird Flu) Virus ” for more information on this process. ...

  11. Plague: Frequently Asked Questions

    Science.gov (United States)

    ... plague? Plague is an infectious disease that affects rodents, certain other animals, and humans. It is caused ... of plague? Fleas become infected by feeding on rodents, such as chipmunks, prairie dogs, ground squirrels, mice, ...

  12. Protection of chickens against avian hepatitis E virus (avian HEV) infection by immunization with recombinant avian HEV capsid protein.

    Science.gov (United States)

    Guo, H; Zhou, E M; Sun, Z F; Meng, X J

    2007-04-12

    Avian hepatitis E virus (avian HEV) is an emerging virus associated with hepatitis-splenomegaly syndrome in chickens in North America. Avian HEV is genetically and antigenically related to human HEV, the causative agent of hepatitis E in humans. In the lack of a practical animal model, avian HEV infection in chickens has been used as a model to study human HEV replication and pathogenesis. A 32 kDa recombinant ORF2 capsid protein of avian HEV expressed in Escherichia coli was found having similar antigenic structure as that of human HEV containing major neutralizing epitopes. To determine if the capsid protein of avian HEV can be used as a vaccine, 20 chickens were immunized with purified avian HEV recombinant protein with aluminum as adjuvant and another 20 chickens were mock immunized with KLH precipitated in aluminum as controls. Both groups of chickens were subsequently challenged with avian HEV. All the tested mock-immunized control chickens developed typical avian HEV infection characterized by viremia, fecal virus shedding and seroconversion to avian HEV antibodies. Gross hepatic lesions were also found in portion of these chickens. In contrast, none of the tested chickens immunized with avian HEV capsid protein had detectable viremia, fecal virus shedding or observable gross hepatitis lesions. The results from this study suggested that immunization of chickens with avian HEV recombinant ORF2 capsid protein with aluminum as adjuvant can induce protective immunity against avian HEV infection. Chickens are a useful small animal model to study anti-HEV immunity and pathogenesis.

  13. Findings of bacterial microflora in piglets infected with conventional swine plague

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    Prodanov Jasna

    2002-01-01

    Full Text Available Piglets infected with the conventional swine plague virus as a result of secondary bacterial infections sometimes show an insufficiently clear clinical and pathoanatomical picture, which is why the very procedure of diagnosis is complex and the final diagnosis unreliable. That is why these investigations were aimed at examining the presence of bacterial microflora in diseased and dead pilgets which were found to have the viral antigen for CSP using the fluorescent antibody technique, in cases where the pathomorphological finding was not characteristic for conventional swine plague. Autopsies of dead piglets most often showed changes in the digestive tract and lungs, with resulting technopathy and diseases of infective nature. Such findings on knowledge of a present bacterial microflora are especially important in cases when conventional swine plague is controlled on farms and an announcement that the disease has been contained is in the offing.

  14. Pneumonic Plague

    Science.gov (United States)

    ... Specific Hazards Bioterrorism A-Z Anthrax (Bacillus anthracis) Arenaviruses Treatment & Infection Control Specimen Submission & Lab Testing Education & ... hemorrhagic fevers (filoviruses [e.g., Ebola, Marburg] and arenaviruses [e.g., Lassa, Machupo]) Yersinia pestis (plague) Fact ...

  15. Immune responses to plague infection in wild Rattus rattus, in Madagascar: a role in foci persistence?

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    Voahangy Andrianaivoarimanana

    Full Text Available BACKGROUND: Plague is endemic within the central highlands of Madagascar, where its main reservoir is the black rat, Rattus rattus. Typically this species is considered susceptible to plague, rapidly dying after infection inducing the spread of infected fleas and, therefore, dissemination of the disease to humans. However, persistence of transmission foci in the same area from year to year, supposes mechanisms of maintenance among which rat immune responses could play a major role. Immunity against plague and subsequent rat survival could play an important role in the stabilization of the foci. In this study, we aimed to investigate serological responses to plague in wild black rats from endemic areas of Madagascar. In addition, we evaluate the use of a recently developed rapid serological diagnostic test to investigate the immune response of potential reservoir hosts in plague foci. METHODOLOGY/PRINCIPAL FINDINGS: We experimentally infected wild rats with Yersinia pestis to investigate short and long-term antibody responses. Anti-F1 IgM and IgG were detected to evaluate this antibody response. High levels of anti-F1 IgM and IgG were found in rats one and three weeks respectively after challenge, with responses greatly differing between villages. Plateau in anti-F1 IgM and IgG responses were reached for as few as 500 and 1500 colony forming units (cfu inoculated respectively. More than 10% of rats were able to maintain anti-F1 responses for more than one year. This anti-F1 response was conveniently followed using dipsticks. CONCLUSION/SIGNIFICANCE: Inoculation of very few bacteria is sufficient to induce high immune response in wild rats, allowing their survival after infection. A great heterogeneity of rat immune responses was found within and between villages which could heavily impact on plague epidemiology. In addition, results indicate that, in the field, anti-F1 dipsticks are efficient to investigate plague outbreaks several months after

  16. Infection of Avian Pox Virus in Oriental Turtle-Doves

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    Kyung-Yeon Eo1, Young-Hoan Kim2, Kwang-Hyun Cho3, Jong-Sik Jang4, Tae-Hwan Kim5, Dongmi Kwak5 and Oh-Deog Kwon5*

    2011-10-01

    Full Text Available Three Oriental Turtle-doves (Streptopelia orientalis exhibiting lethargy, dyspnea, poor physical condition, and poor flight endurance, were rescued and referred to the Animal Health Center, Seoul Zoo, Korea. The doves had wart-like lesions on the legs and head. All of them died the following day after arrival, with the exception of one that survived for 6 days. Diphtheritic membranes on the tongue and oral mucosa were apparent at necropsy. Avian pox virus infection was suspected based on the proliferative skin lesions and oral diphtheritic lesions. Infection of the avian pox virus was confirmed by PCR using primers specific to the 4b core protein gene of avian pox virus. All cases were diagnosed with avian pox virus infection. This is believed to be the first description on natural infection of avian pox in Oriental Turtle-doves in Korea.

  17. Histopathological observation of immunized rhesus macaques with plague vaccines after subcutaneous infection of Yersinia pestis.

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    Guang Tian

    Full Text Available In our previous study, complete protection was observed in Chinese-origin rhesus macaques immunized with SV1 (20 µg F1 and 10 µg rV270 and SV2 (200 µg F1 and 100 µg rV270 subunit vaccines and with EV76 live attenuated vaccine against subcutaneous challenge with 6×10(6 CFU of Y. pestis. In the present study, we investigated whether the vaccines can effectively protect immunized animals from any pathologic changes using histological and immunohistochemical techniques. In addition, the glomerular basement membranes (GBMs of the immunized animals and control animals were checked by electron microscopy. The results show no signs of histopathological lesions in the lungs, livers, kidneys, lymph nodes, spleens and hearts of the immunized animals at Day 14 after the challenge, whereas pathological alterations were seen in the corresponding tissues of the control animals. Giemsa staining, ultrastructural examination, and immunohistochemical staining revealed bacteria in some of the organs of the control animals, whereas no bacterium was observed among the immunized animals. Ultrastructural observation revealed that no glomerular immune deposits on the GBM. These observations suggest that the vaccines can effectively protect animals from any pathologic changes and eliminate Y. pestis from the immunized animals. The control animals died from multi-organ lesions specifically caused by the Y. pestis infection. We also found that subcutaneous infection of animals with Y. pestis results in bubonic plague, followed by pneumonic and septicemic plagues. The histopathologic features of plague in rhesus macaques closely resemble those of rodent and human plagues. Thus, Chinese-origin rhesus macaques serve as useful models in studying Y. pestis pathogenesis, host response and the efficacy of new medical countermeasures against plague.

  18. Selective isolation of Yersinia pestis from plague-infected fleas

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    Sarovich, Derek S.; Colman, Rebecca E.; Price, Erin P.; Chung, Wai Kwan; Lee, Judy; Schupp, James M.; Alexander, James; Keim, Paul; Wagner., David M.

    2010-01-01

    We evaluated Yersinia CIN agar for the isolation of Yersinia pestis from infected fleas. CIN media is effective for the differentiation of Y. pestis from flea commensal flora and is sufficiently inhibitory to other bacteria that typically outcompete Y. pestis after 48 hours of growth using less selective media. PMID:20385178

  19. Inhaled Liposomal Ciprofloxacin Protects against a Lethal Infection in a Murine Model of Pneumonic Plague

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    Hamblin, Karleigh A.; Armstrong, Stuart J.; Barnes, Kay B.; Davies, Carwyn; Laws, Thomas; Blanchard, James D.; Harding, Sarah V.; Atkins, Helen S.

    2017-01-01

    Inhalation of Yersinia pestis can lead to pneumonic plague, which without treatment is inevitably fatal. Two novel formulations of liposome-encapsulated ciprofloxacin, ‘ciprofloxacin for inhalation’ (CFI, Lipoquin®) and ‘dual release ciprofloxacin for inhalation’ (DRCFI, Pulmaquin®) containing CFI and ciprofloxacin solution, are in development. These were evaluated as potential therapies for infection with Y. pestis. In a murine model of pneumonic plague, human-like doses of aerosolized CFI, aerosolized DRCFI or intraperitoneal (i.p.) ciprofloxacin were administered at 24 h (representing prophylaxis) or 42 h (representing treatment) post-challenge. All three therapies provided a high level of protection when administered 24 h post-challenge. A single dose of CFI, but not DRCFI, significantly improved survival compared to a single dose of ciprofloxacin. Furthermore, single doses of CFI and DRCFI reduced bacterial burden in lungs and spleens to below the detectable limit at 60 h post-challenge. When therapy was delayed until 42 h post-challenge, a single dose of CFI or DRCFI offered minimal protection. However, single doses of CFI or DRCFI were able to significantly reduce the bacterial burden in the spleen compared to empty liposomes. A three-day treatment regimen of ciprofloxacin, CFI, or DRCFI resulted in high levels of protection (90–100% survival). This study suggests that CFI and DRCFI may be useful therapies for Y. pestis infection, both as prophylaxis and for the treatment of plague. PMID:28220110

  20. Avian Influenza: Mixed Infections and Missing Viruses

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    David E. Wentworth

    2013-08-01

    Full Text Available A high prevalence and diversity of avian influenza (AI viruses were detected in a population of wild mallards sampled during summer 2011 in California, providing an opportunity to compare results obtained before and after virus culture. We tested cloacal swab samples prior to culture by matrix real-time PCR, and by amplifying and sequencing a 640bp portion of the hemagglutinin (HA gene. Each sample was also inoculated into embryonated chicken eggs, and full genome sequences were determined for cultured viruses. While low matrix Ct values were a good predictor of virus isolation from eggs, samples with high or undetectable Ct values also yielded isolates. Furthermore, a single passage in eggs altered the occurrence and detection of viral strains, and mixed infections (different HA subtypes were detected less frequently after culture. There is no gold standard or perfect reference comparison for surveillance of unknown viruses, and true negatives are difficult to distinguish from false negatives. This study showed that sequencing samples prior to culture increases the detection of mixed infections and enhances the identification of viral strains and sequences that may have changed or even disappeared during culture.

  1. Avian influenza: mixed infections and missing viruses.

    Science.gov (United States)

    Lindsay, LeAnn L; Kelly, Terra R; Plancarte, Magdalena; Schobel, Seth; Lin, Xudong; Dugan, Vivien G; Wentworth, David E; Boyce, Walter M

    2013-08-05

    A high prevalence and diversity of avian influenza (AI) viruses were detected in a population of wild mallards sampled during summer 2011 in California, providing an opportunity to compare results obtained before and after virus culture. We tested cloacal swab samples prior to culture by matrix real-time PCR, and by amplifying and sequencing a 640bp portion of the hemagglutinin (HA) gene. Each sample was also inoculated into embryonated chicken eggs, and full genome sequences were determined for cultured viruses. While low matrix Ct values were a good predictor of virus isolation from eggs, samples with high or undetectable Ct values also yielded isolates. Furthermore, a single passage in eggs altered the occurrence and detection of viral strains, and mixed infections (different HA subtypes) were detected less frequently after culture. There is no gold standard or perfect reference comparison for surveillance of unknown viruses, and true negatives are difficult to distinguish from false negatives. This study showed that sequencing samples prior to culture increases the detection of mixed infections and enhances the identification of viral strains and sequences that may have changed or even disappeared during culture.

  2. Determination and analysis of the complete genomic sequence of avian hepatitis E virus (avian HEV) and attempts to infect rhesus monkeys with avian HEV.

    Science.gov (United States)

    Huang, F F; Sun, Z F; Emerson, S U; Purcell, R H; Shivaprasad, H L; Pierson, F W; Toth, T E; Meng, X J

    2004-06-01

    Avian hepatitis E virus (avian HEV), recently identified from a chicken with hepatitis-splenomegaly syndrome in the United States, is genetically and antigenically related to human and swine HEVs. In this study, sequencing of the genome was completed and an attempt was made to infect rhesus monkeys with avian HEV. The full-length genome of avian HEV, excluding the poly(A) tail, is 6654 bp in length, which is about 600 bp shorter than that of human and swine HEVs. Similar to human and swine HEV genomes, the avian HEV genome consists of a short 5' non-coding region (NCR) followed by three partially overlapping open reading frames (ORFs) and a 3'NCR. Avian HEV shares about 50 % nucleotide sequence identity over the complete genome, 48-51 % identity in ORF1, 46-48 % identity in ORF2 and only 29-34 % identity in ORF3 with human and swine HEV strains. Significant genetic variations such as deletions and insertions, particularly in ORF1 of avian HEV, were observed. However, motifs in the putative functional domains of ORF1, such as the helicase and methyltransferase, were relatively conserved between avian HEV and mammalian HEVs, supporting the conclusion that avian HEV is a member of the genus Hepevirus. Phylogenetic analysis revealed that avian HEV represents a branch distinct from human and swine HEVs. Swine HEV infects non-human primates and possibly humans and thus may be zoonotic. An attempt was made to determine whether avian HEV also infects across species by experimentally inoculating two rhesus monkeys with avian HEV. Evidence of virus infection was not observed in the inoculated monkeys as there was no seroconversion, viraemia, faecal virus shedding or serum liver enzyme elevation. The results from this study confirmed that avian HEV is related to, but distinct from, human and swine HEVs; however, unlike swine HEV, avian HEV is probably not transmissible to non-human primates.

  3. Avian influenza in shorebirds: experimental infection of ruddy turnstones (Arenaria interpres) with avian influenza virus

    Science.gov (United States)

    Hall, Jeffrey S.; Krauss, Scott; Franson, J. Christian; TeSlaa, Joshua L.; Nashold, Sean W.; Stallknecht, David E.; Webby, Richard J.; Webster, Robert G.

    2013-01-01

    Background: Low pathogenic avian influenza viruses (LPAIV) have been reported in shorebirds, especially at Delaware Bay, USA, during spring migration. However, data on patterns of virus excretion, minimal infectious doses, and clinical outcome are lacking. The ruddy turnstone (Arenaria interpres) is the shorebird species with the highest prevalence of influenza virus at Delaware Bay. Objectives: The primary objective of this study was to experimentally assess the patterns of influenza virus excretion, minimal infectious doses, and clinical outcome in ruddy turnstones. Methods: We experimentally challenged ruddy turnstones using a common LPAIV shorebird isolate, an LPAIV waterfowl isolate, or a highly pathogenic H5N1 avian influenza virus. Cloacal and oral swabs and sera were analyzed from each bird. Results: Most ruddy turnstones had pre-existing antibodies to avian influenza virus, and many were infected at the time of capture. The infectious doses for each challenge virus were similar (103·6–104·16 EID50), regardless of exposure history. All infected birds excreted similar amounts of virus and showed no clinical signs of disease or mortality. Influenza A-specific antibodies remained detectable for at least 2 months after inoculation. Conclusions: These results provide a reference for interpretation of surveillance data, modeling, and predicting the risks of avian influenza transmission and movement in these important hosts.

  4. Avian influenza infection alters fecal odor in mallards.

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    Bruce A Kimball

    Full Text Available Changes in body odor are known to be a consequence of many diseases. Much of the published work on disease-related and body odor changes has involved parasites and certain cancers. Much less studied have been viral diseases, possibly due to an absence of good animal model systems. Here we studied possible alteration of fecal odors in animals infected with avian influenza viruses (AIV. In a behavioral study, inbred C57BL/6 mice were trained in a standard Y-maze to discriminate odors emanating from feces collected from mallard ducks (Anas platyrhynchos infected with low-pathogenic avian influenza virus compared to fecal odors from non-infected controls. Mice could discriminate odors from non-infected compared to infected individual ducks on the basis of fecal odors when feces from post-infection periods were paired with feces from pre-infection periods. Prompted by this indication of odor change, fecal samples were subjected to dynamic headspace and solvent extraction analyses employing gas chromatography/mass spectrometry to identify chemical markers indicative of AIV infection. Chemical analyses indicated that AIV infection was associated with a marked increase of acetoin (3-hydroxy-2-butanone in feces. These experiments demonstrate that information regarding viral infection exists via volatile metabolites present in feces. Further, they suggest that odor changes following virus infection could play a role in regulating behavior of conspecifics exposed to infected individuals.

  5. Avian bornavirus in the urine of infected birds

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    Villalobos AR

    2012-06-01

    Full Text Available J Jill Heatley,1 Alice R Villalobos21Zoological Medicine, 2Department of Nutrition & Food Science, Texas A&M University, College of Veterinary Medicine and Biomedical Sciences, College Station, TX, USAAbstract: Avian bornavirus (ABV causes proventricular dilatation disease in multiple avian species. In severe clinical disease, the virus, while primarily neurotropic, can be detected in many organs, including the kidneys. We postulated that ABV could be shed by the kidneys and found in the urine of infected birds. Immunohistochemical staining demonstrated viral N and P proteins of ABV within the renal tubules. We adapted a nonsurgical method of urine collection for use in parrots known to be shedding ABV in their droppings. We obtained urine without feces, and results were compared with swabs of fresh voided feces. Reverse transcription–polymerase chain reaction assay performed on these paired samples from five birds indicated that ABV was shed in quantity in the urine of infected birds, and a single sample was urine-positive and fecal-negative. We suggest that urine sampling may be a superior sample for detection of birds shedding ABV, and advocate that additional birds, known to be shedding or infected with ABV, should be investigated via this method.Keywords: avian bornavirus, Psittaciformes, parrot, urine, proventricular dilatation disease

  6. Plague Factsheet

    Science.gov (United States)

    ... areas through three techniques: Environmental management Public health education Preventive drug therapy Environmental Management Preventing epidemic plague requires the reducing or eliminating house rat populations in both urban and rural areas. Control of plague in such situations requires two ...

  7. Risk Perceptions for Avian Influenza Virus Infection among Poultry Workers, China

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    Yu, Qi; Liu, Linqing; Pu, Juan; Zhao, Jingyi; Sun, Yipeng; Shen, Guangnian; Wei, Haitao; Zhu, Junjie; Zheng, Ruifeng; Xiong, Dongyan; Liu, Xiaodong; Liu, Jinhua

    2013-01-01

    To determine risk for avian influenza virus infection, we conducted serologic surveillance for H5 and H9 subtypes among poultry workers in Beijing, China, 2009–2010, and assessed workers’ understanding of avian influenza. We found that poultry workers had considerable risk for infection with H9 subtypes. Increasing their knowledge could prevent future infections.

  8. Avian cathelicidins: paradigms for the development of anti-infectives.

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    van Dijk, A; Molhoek, E M; Bikker, F J; Yu, P-L; Veldhuizen, E J A; Haagsman, H P

    2011-11-21

    The broad-spectrum defense system based on host defense peptides (HDPs) is evolutionary very old and many invertebrates rely on this system for protection from bacterial infections. However, in vertebrates the system remained important in spite of the superposition of a very sophisticated adaptive immune system. The cathelicidins comprise a major group of HDPs in mammals. About six years ago it was first described that cathelicidins are also present in birds. Here we review the properties and biological activities of the recently discovered avian cathelicidins and their potential to be used as a paradigm for the development of anti-infectives. Like the mammalian cathelicidins, avian cathelicidins exert direct antimicrobial activities but can also selectively boost host immune responses by regulation of cytokine production and recruitment of immune cells. In addition, it was found that chicken cathelicidins bind endotoxins and dampen the endotoxin-mediated inflammatory response. Molecular dissection has allowed identification of different structural elements involved in bacterial killing and immunomodulation. These studies have enabled the design of small HDP-based antibiotics with specific functions, i.e. having primarily immunomodulatory or antimicrobial activities. Since the immunomodulatory effects may, to a certain degree, be species-specific, we hypothesize that poultry-specific antibiotics can be developed based on avian cathelicidins.

  9. Human Infection with Avian Influenza A(H7N9) Virus - China

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    ... Biorisk reduction Human infection with avian influenza A(H7N9) virus – China Disease outbreak news 18 January 2017 ... laboratory-confirmed human infection with avian influenza A(H7N9) virus and on 12 January 2017, the Health ...

  10. Evidence of widespread infection of avian hepatitis E virus (avian HEV) in chickens from Spain.

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    Peralta, Bibiana; Biarnés, Mar; Ordóñez, Germán; Porta, Ramón; Martín, Marga; Mateu, Enric; Pina, Sonia; Meng, Xiang-Jin

    2009-05-28

    In the present work, 262 serum samples and 29 faeces pools from chickens coming from 29 healthy flocks were analysed by RT-PCR for detection of avian HEV and by ELISA using an aHEV derived antigen for detection of anti-HEV IgG. Additionally, other 300 randomly selected serum samples were also analysed by RT-PCR. Seven serum samples were positive to RNA detection. Sequence analysis of both the helicase and the capsid genes revealed that the Spanish isolates were clustered together and close related to those strains from the United States isolated from farms with HSS. On the serology study, 26/29 flocks had at least one positive animal (89.7%) and chickens older than 40 weeks were found to have higher seropositivities compared to the rest of age groups. Within positive farms, the proportion of positive animals ranged from 20% to 80%. This is the first report of aHEV sequences in chickens from Europe. Further studies are needed to elucidate the clinical significance of avian HEV infections in Europe.

  11. Are Carnivores Universally Good Sentinels of Plague?

    OpenAIRE

    Brinkerhoff, R. Jory; Collinge, Sharon K.; Bai, Ying; Ray, Chris

    2009-01-01

    Sylvatic plague, caused by the bacterium Yersinia pestis, is a flea-borne disease that primarily affects rodents but has been detected in over 200 mammal species worldwide. Mammalian carnivores are routinely surveyed as sentinels of local plague activity, since they can present antibodies to Y. pestis infection but show few clinical signs. In Boulder County, Colorado, USA, plague epizootic events are episodic and occur in black-tailed prairie dogs. Enzootic hosts are unidentified as are plagu...

  12. Generation and infectivity titration of an infectious stock of avian hepatitis E virus (HEV) in chickens and cross-species infection of turkeys with avian HEV.

    Science.gov (United States)

    Sun, Z F; Larsen, C T; Huang, F F; Billam, P; Pierson, F W; Toth, T E; Meng, X J

    2004-06-01

    Avian hepatitis E virus (HEV), a novel virus identified from chickens with hepatitis-splenomegaly syndrome in the United States, is genetically and antigenically related to human HEV. In order to further characterize avian HEV, an infectious viral stock with a known infectious titer must be generated, as HEV cannot be propagated in vitro. Bile and feces collected from specific-pathogen-free (SPF) chickens experimentally infected with avian HEV were used to prepare an avian HEV infectious stock as a 10% suspension of positive fecal and bile samples in phosphate-buffered saline. The infectivity titer of this infectious stock was determined by inoculating 1-week-old SPF chickens intravenously with 200 microl of each of serial 10-fold dilutions (10(-2) to 10(-6)) of the avian HEV stock (two chickens were inoculated with each dilution). All chickens inoculated with the 10(-2) to 10(-4) dilutions of the infectious stock and one of the two chickens inoculated with the 10(-5) dilution, but neither of the chickens inoculated with the 10(-6) dilution, became seropositive for anti-avian HEV antibody at 4 weeks postinoculation (wpi). Two serologically negative contact control chickens housed together with chickens inoculated with the 10(-2) dilution also seroconverted at 8 wpi. Viremia and shedding of virus in feces were variable in chickens inoculated with the 10(-2) to 10(-5) dilutions but were not detectable in those inoculated with the 10(-6) dilution. The infectivity titer of the infectious avian HEV stock was determined to be 5 x 10(5) 50% chicken infectious doses (CID(50)) per ml. Eight 1-week-old turkeys were intravenously inoculated with 10(5) CID(50) of avian HEV, and another group of nine turkeys were not inoculated and were used as controls. The inoculated turkeys seroconverted at 4 to 8 wpi. In the inoculated turkeys, viremia was detected at 2 to 6 wpi and shedding of virus in feces was detected at 4 to 7 wpi. A serologically negative contact control turkey housed

  13. Evidence of infection with H4 and H11 avian influenza viruses among Lebanese chicken growers.

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    Ghazi Kayali

    Full Text Available Human infections with H5, H7, and H9 avian influenza viruses are well documented. Exposure to poultry is the most important risk factor for humans becoming infected with these viruses. Data on human infection with other low pathogenicity avian influenza viruses is sparse but suggests that such infections may occur. Lebanon is a Mediterranean country lying under two major migratory birds flyways and is home to many wild and domestic bird species. Previous reports from this country demonstrated that low pathogenicity avian influenza viruses are in circulation but highly pathogenic H5N1 viruses were not reported. In order to study the extent of human infection with avian influenza viruses in Lebanon, we carried out a seroprevalence cross-sectional study into which 200 poultry-exposed individuals and 50 non-exposed controls were enrolled. We obtained their sera and tested it for the presence of antibodies against avian influenza viruses types H4 through H16 and used a questionnaire to collect exposure data. Our microneutralization assay results suggested that backyard poultry growers may have been previously infected with H4 and H11 avian influenza viruses. We confirmed these results by using a horse red blood cells hemagglutination inhibition assay. Our data also showed that farmers with antibodies against each virus type clustered in a small geographic area suggesting that unrecognized outbreaks among birds may have led to these human infections. In conclusion, this study suggests that occupational exposure to chicken is a risk factor for infection with avian influenza especially among backyard growers and that H4 and H11 influenza viruses may possess the ability to cross the species barrier to infect humans.

  14. MHC-I affects infection intensity but not infection status with a frequent avian malaria parasite in blue tits.

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    Helena Westerdahl

    Full Text Available Host resistance against parasites depends on three aspects: the ability to prevent, control and clear infections. In vertebrates the immune system consists of innate and adaptive immunity. Innate immunity is particularly important for preventing infection and eradicating established infections at an early stage while adaptive immunity is slow, but powerful, and essential for controlling infection intensities and eventually clearing infections. Major Histocompatibility Complex (MHC molecules are central in adaptive immunity, and studies on parasite resistance and MHC in wild animals have found effects on both infection intensity (parasite load and infection status (infected or not. It seems MHC can affect both the ability to control infection intensities and the ability to clear infections. However, these two aspects have rarely been considered simultaneously, and their relative importance in natural populations is therefore unclear. Here we investigate if MHC class I genotype affects infection intensity and infection status with a frequent avian malaria infection Haemoproteus majoris in a natural population of blue tits Cyanistes caeruleus. We found a significant negative association between a single MHC allele and infection intensity but no association with infection status. Blue tits that carry a specific MHC allele seem able to suppress H. majoris infection intensity, while we have no evidence that this allele also has an effect on clearance of the H. majoris infection, a result that is in contrast with some previous studies of MHC and avian malaria. A likely explanation could be that the clearance rate of avian malaria parasites differs between avian malaria lineages and/or between avian hosts.

  15. MHC-I affects infection intensity but not infection status with a frequent avian malaria parasite in blue tits.

    Science.gov (United States)

    Westerdahl, Helena; Stjernman, Martin; Råberg, Lars; Lannefors, Mimi; Nilsson, Jan-Åke

    2013-01-01

    Host resistance against parasites depends on three aspects: the ability to prevent, control and clear infections. In vertebrates the immune system consists of innate and adaptive immunity. Innate immunity is particularly important for preventing infection and eradicating established infections at an early stage while adaptive immunity is slow, but powerful, and essential for controlling infection intensities and eventually clearing infections. Major Histocompatibility Complex (MHC) molecules are central in adaptive immunity, and studies on parasite resistance and MHC in wild animals have found effects on both infection intensity (parasite load) and infection status (infected or not). It seems MHC can affect both the ability to control infection intensities and the ability to clear infections. However, these two aspects have rarely been considered simultaneously, and their relative importance in natural populations is therefore unclear. Here we investigate if MHC class I genotype affects infection intensity and infection status with a frequent avian malaria infection Haemoproteus majoris in a natural population of blue tits Cyanistes caeruleus. We found a significant negative association between a single MHC allele and infection intensity but no association with infection status. Blue tits that carry a specific MHC allele seem able to suppress H. majoris infection intensity, while we have no evidence that this allele also has an effect on clearance of the H. majoris infection, a result that is in contrast with some previous studies of MHC and avian malaria. A likely explanation could be that the clearance rate of avian malaria parasites differs between avian malaria lineages and/or between avian hosts.

  16. Ascorbic acid inhibits replication and infectivity of avian RNA tumor virus

    Energy Technology Data Exchange (ETDEWEB)

    BISSELL, MINA J; HATIE, CARROLL; FARSON, DEBORAH A.; SCHWARZ, RICHARD I.; SOO, WHAI-JEN

    1980-04-01

    Ascorbic acid, at nontoxic concentrations, causes a substantial reduction in the ability of avian tumor viruses to replicate in both primary avian tendon cells and chicken embryo fibroblasts. The virus-infected cultures appear to be less transformed in the presence of ascorbic acid by the criteria of morphology, reduced glucose uptake, and increased collagen synthesis. The vitamin does not act by altering the susceptibility of the cells to initial infection and transformation, but instead appears to interfere with the spread of infection through a reduction in virus replication and virus infectivity. The effect is reversible and requires the continuous presence of the vitamin in the culture medium.

  17. Plague Prevention

    Science.gov (United States)

    ... your pet becomes sick, seek care from a veterinarian as soon as possible. Do not allow dogs or cats that roam free in endemic areas to sleep on your bed. Note: A plague vaccine is no longer available in the United States. ...

  18. Subclinical avian hepatitis E virus infection in layer flocks in the United States.

    Science.gov (United States)

    Gerber, Priscilla F; Trampel, Darrell W; Willinghan, Eric M; Billam, Padma; Meng, Xiang-Jin; Opriessnig, Tanja

    2015-12-01

    The objective of this study was to determine patterns of avian HEV infection in naturally infected chicken farms. A total of 310 serum samples and 62 pooled fecal samples were collected from 62 chicken flocks on seven commercial in-line egg farms in the Midwestern United States and tested for avian HEV circulation. Serum samples were tested for the presence of anti-avian HEV IgY antibodies by a fluorescent microbead immunoassay (FMIA) which was developed for this study. The FMIA was validated using archived samples of chickens with known exposure (n = 96) and compared to the results obtained with an enzyme-linked immunosorbent assay (ELISA) based on the same capture antigen. There was an overall substantial agreement between the two assays (κ = 0.63) with earlier detection of positive chickens by the FMIA (P = 0.04). On the seven farms investigated, the overall prevalence of anti-avian HEV IgY antibodies in serum samples from commercial chickens was 44.8% (20-82% per farm). Fecal samples were tested for avian HEV RNA by a nested reverse-transcriptase PCR. The overall detection rate of avian HEV RNA in fecal samples was 62.9% (0-100% per farm). Sequencing analyses of partial helicase and capsid genes showed that different avian HEV genotype 2 strains were circulating within a farm. However, no correlation was found between avian HEV RNA detection and egg production, egg weight or mortality. In conclusion, avian HEV infection is widespread among clinically healthy laying hens in the United States.

  19. Investigating avian influenza infection hotspots in old-world shorebirds.

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    Nicolas Gaidet

    Full Text Available Heterogeneity in the transmission rates of pathogens across hosts or environments may produce disease hotspots, which are defined as specific sites, times or species associations in which the infection rate is consistently elevated. Hotspots for avian influenza virus (AIV in wild birds are largely unstudied and poorly understood. A striking feature is the existence of a unique but consistent AIV hotspot in shorebirds (Charadriiformes associated with a single species at a specific location and time (ruddy turnstone Arenaria interpres at Delaware Bay, USA, in May. This unique case, though a valuable reference, limits our capacity to explore and understand the general properties of AIV hotspots in shorebirds. Unfortunately, relatively few shorebirds have been sampled outside Delaware Bay and they belong to only a few shorebird families; there also has been a lack of consistent oropharyngeal sampling as a complement to cloacal sampling. In this study we looked for AIV hotspots associated with other shorebird species and/or with some of the larger congregation sites of shorebirds in the old world. We assembled and analysed a regionally extensive dataset of AIV prevalence from 69 shorebird species sampled in 25 countries across Africa and Western Eurasia. Despite this diverse and extensive coverage we did not detect any new shorebird AIV hotspots. Neither large shorebird congregation sites nor the ruddy turnstone were consistently associated with AIV hotspots. We did, however, find a low but widespread circulation of AIV in shorebirds that contrast with the absence of AIV previously reported in shorebirds in Europe. A very high AIV antibody prevalence coupled to a low infection rate was found in both first-year and adult birds of two migratory sandpiper species, suggesting the potential existence of an AIV hotspot along their migratory flyway that is yet to be discovered.

  20. Gene expression responses to highly pathogenic avian influenza H5N1 virus infections in ducks

    Science.gov (United States)

    Differences in host response to infection with avian influenza (AI) viruses were investigated by identifying genes differentially expressed in tissues of infected ducks. Clear differences in pathogenicity were observed among ducks inoculated with five H5N1 HPAI viruses. Virus titers in tissues cor...

  1. Experimental avian paramyxovirus serotype-3 infection in chickens and turkeys.

    Science.gov (United States)

    Kumar, Sachin; Militino Dias, Flavia; Nayak, Baibaswata; Collins, Peter L; Samal, Siba K

    2010-01-01

    Avian paramyxoviruses (APMV) are divided into nine serotypes. Newcastle disease virus (APMV-1) is the most extensively characterized, while relatively little information is available for the other APMV serotypes. In the present study, we examined the pathogenicity of two divergent strains of APMV-3, Netherlands and Wisconsin, in (i) 9-day-old embryonated chicken eggs, (ii) 1-day-old specific pathogen free (SPF) chicks and turkeys, and (iii) 2-week-old SPF chickens and turkeys. The mean death time in 9-day-old embryonated chicken eggs was 112 h for APMV-3 strain Netherlands and > 168 h for strain Wisconsin. The intracerebral pathogenicity index in 1-day-old chicks for strain Netherlands was 0.39 and for strain Wisconsin was zero. Thus, both strains are lentogenic. Both the strains replicated well in brain tissue when inoculated intracerebrally in 1-day-old SPF chicks, but without causing death. Mild respiratory disease signs were observed in 1-day-old chickens and turkeys when inoculated through oculonasal route with either strain. There were no overt signs of illness in 2-weeks-old chickens and turkeys by either strain, although all the birds seroconverted after infection. The viruses were isolated predominantly from brain, lungs, spleens, trachea, pancreas and kidney. Immunohistochemistry studies also showed the presence of large amount of viral antigens in both epithelial and sub-epithelial lining of respiratory and alimentary tracts. Our result suggests systemic spread of APMV-3 even though the viral fusion glycoprotein does not contain the canonical furin proteases cleavage site. Furthermore, there was little or no disease despite systemic viral spread and abundant viral replication in all the tissues tested.

  2. Little evidence of subclinical avian influenza virus infections among rural villagers in Cambodia.

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    Gregory C Gray

    Full Text Available In 2008, 800 adults living within rural Kampong Cham Province, Cambodia were enrolled in a prospective cohort study of zoonotic influenza transmission. After enrollment, participants were contacted weekly for 24 months to identify acute influenza-like illnesses (ILI. Follow-up sera were collected at 12 and 24 months. A transmission substudy was also conducted among the family contacts of cohort members reporting ILI who were influenza A positive. Samples were assessed using serological or molecular techniques looking for evidence of infection with human and avian influenza viruses. Over 24 months, 438 ILI investigations among 284 cohort members were conducted. One cohort member was hospitalized with a H5N1 highly pathogenic avian influenza (HPAI virus infection and withdrew from the study. Ninety-seven ILI cases (22.1% were identified as influenza A virus infections by real-time RT-PCR; none yielded evidence for AIV. During the 2 years of follow-up, 21 participants (3.0% had detectable antibody titers (≥ 1:10 against the studied AIVs: 1 against an avian-like A/Migratory duck/Hong Kong/MPS180/2003(H4N6, 3 against an avian-like A/Teal/Hong Kong/w312/97(H6N1, 9 (3 of which had detectible antibody titers at both 12- and 24-month follow-up against an avian-like A/Hong Kong/1073/1999(H9N2, 6 (1 detected at both 12- and 24-month follow-up against an avian-like A/Duck/Memphis/546/74(H11N9, and 2 against an avian-like A/Duck/Alberta/60/76(H12N5. With the exception of the one hospitalized cohort member with H5N1 infection, no other symptomatic avian influenza infections were detected among the cohort. Serological evidence for subclinical infections was sparse with only one subject showing a 4-fold rise in microneutralization titer over time against AvH12N5. In summary, despite conducting this closely monitored cohort study in a region enzootic for H5N1 HPAI, we were unable to detect subclinical avian influenza infections, suggesting either that these

  3. Little Evidence of Subclinical Avian Influenza Virus Infections among Rural Villagers in Cambodia

    Science.gov (United States)

    Gray, Gregory C.; Krueger, Whitney S.; Chum, Channimol; Putnam, Shannon D.; Wierzba, Thomas F.; Heil, Gary L.; Anderson, Benjamin D.; Yasuda, Chadwick Y.; Williams, Maya; Kasper, Matthew R.; Saphonn, Vonthanak; Blair, Patrick J.

    2014-01-01

    In 2008, 800 adults living within rural Kampong Cham Province, Cambodia were enrolled in a prospective cohort study of zoonotic influenza transmission. After enrollment, participants were contacted weekly for 24 months to identify acute influenza-like illnesses (ILI). Follow-up sera were collected at 12 and 24 months. A transmission substudy was also conducted among the family contacts of cohort members reporting ILI who were influenza A positive. Samples were assessed using serological or molecular techniques looking for evidence of infection with human and avian influenza viruses. Over 24 months, 438 ILI investigations among 284 cohort members were conducted. One cohort member was hospitalized with a H5N1 highly pathogenic avian influenza (HPAI) virus infection and withdrew from the study. Ninety-seven ILI cases (22.1%) were identified as influenza A virus infections by real-time RT-PCR; none yielded evidence for AIV. During the 2 years of follow-up, 21 participants (3.0%) had detectable antibody titers (≥1∶10) against the studied AIVs: 1 against an avian-like A/Migratory duck/Hong Kong/MPS180/2003(H4N6), 3 against an avian-like A/Teal/Hong Kong/w312/97(H6N1), 9 (3 of which had detectible antibody titers at both 12- and 24-month follow-up) against an avian-like A/Hong Kong/1073/1999(H9N2), 6 (1 detected at both 12- and 24-month follow-up) against an avian-like A/Duck/Memphis/546/74(H11N9), and 2 against an avian-like A/Duck/Alberta/60/76(H12N5). With the exception of the one hospitalized cohort member with H5N1 infection, no other symptomatic avian influenza infections were detected among the cohort. Serological evidence for subclinical infections was sparse with only one subject showing a 4-fold rise in microneutralization titer over time against AvH12N5. In summary, despite conducting this closely monitored cohort study in a region enzootic for H5N1 HPAI, we were unable to detect subclinical avian influenza infections, suggesting either that these

  4. Previous infection with a mesogenic strain of Newcastle disease virus affects infection with highly pathogenic avian influenza viruses in chickens

    Science.gov (United States)

    Avian influenza virus (AIV) and Newcastle disease virus (NDV) are two of the most important viruses affecting poultry worldwide, but little is known on the interactions between these two viruses when infecting birds. In a previous study we found that infection of chickens with a mesogenic strain of...

  5. Identification of New World Quails Susceptible to Infection with Avian Leukosis Virus Subgroup J.

    Science.gov (United States)

    Plachý, Jiří; Reinišová, Markéta; Kučerová, Dana; Šenigl, Filip; Stepanets, Volodymyr; Hron, Tomáš; Trejbalová, Kateřina; Elleder, Daniel; Hejnar, Jiří

    2017-02-01

    The J subgroup of avian leukosis virus (ALV-J) infects domestic chickens, jungle fowl, and turkeys. This virus enters the host cell through a receptor encoded by the tvj locus and identified as Na(+)/H(+) exchanger 1. The resistance to avian leukosis virus subgroup J in a great majority of galliform species has been explained by deletions or substitutions of the critical tryptophan 38 in the first extracellular loop of Na(+)/H(+) exchanger 1. Because there are concerns of transspecies virus transmission, we studied natural polymorphisms and susceptibility/resistance in wild galliforms and found the presence of tryptophan 38 in four species of New World quails. The embryo fibroblasts of New World quails are susceptible to infection with avian leukosis virus subgroup J, and the cloned Na(+)/H(+) exchanger 1 confers susceptibility on the otherwise resistant host. New World quails are also susceptible to new avian leukosis virus subgroup J variants but resistant to subgroups A and B and weakly susceptible to subgroups C and D of avian sarcoma/leukosis virus due to obvious defects of the respective receptors. Our results suggest that the avian leukosis virus subgroup J could be transmitted to New World quails and establish a natural reservoir of circulating virus with a potential for further evolution.

  6. Infections with avian pathogenic and fecal Escherichia coli strains display similar lung histopathology and macrophage apoptosis.

    Directory of Open Access Journals (Sweden)

    Fabiana Horn

    Full Text Available The purpose of this study was to compare histopathological changes in the lungs of chickens infected with avian pathogenic (APEC and avian fecal (A(fecal Escherichia coli strains, and to analyze how the interaction of the bacteria with avian macrophages relates to the outcome of the infection. Chickens were infected intratracheally with three APEC strains, MT78, IMT5155, and UEL17, and one non-pathogenic A(fecal strain, IMT5104. The pathogenicity of the strains was assessed by isolating bacteria from lungs, kidneys, and spleens at 24 h post-infection (p.i.. Lungs were examined for histopathological changes at 12, 18, and 24 h p.i. Serial lung sections were stained with hematoxylin and eosin (HE, terminal deoxynucleotidyl dUTP nick end labeling (TUNEL for detection of apoptotic cells, and an anti-O2 antibody for detection of MT78 and IMT5155. UEL17 and IMT5104 did not cause systemic infections and the extents of lung colonization were two orders of magnitude lower than for the septicemic strains MT78 and IMT5155, yet all four strains caused the same extent of inflammation in the lungs. The inflammation was localized; there were some congested areas next to unaffected areas. Only the inflamed regions became labeled with anti-O2 antibody. TUNEL labeling revealed the presence of apoptotic cells at 12 h p.i in the inflamed regions only, and before any necrotic foci could be seen. The TUNEL-positive cells were very likely dying heterophils, as evidenced by the purulent inflammation. Some of the dying cells observed in avian lungs in situ may also be macrophages, since all four avian E. coli induced caspase 3/7 activation in monolayers of HD11 avian macrophages. In summary, both pathogenic and non-pathogenic fecal strains of avian E. coli produce focal infections in the avian lung, and these are accompanied by inflammation and cell death in the infected areas.

  7. Are carnivores universally good sentinels of plague?

    Science.gov (United States)

    Brinkerhoff, R Jory; Collinge, Sharon K; Bai, Ying; Ray, Chris

    2009-10-01

    Sylvatic plague, caused by the bacterium Yersinia pestis, is a flea-borne disease that primarily affects rodents but has been detected in over 200 mammal species worldwide. Mammalian carnivores are routinely surveyed as sentinels of local plague activity, since they can present antibodies to Y. pestis infection but show few clinical signs. In Boulder County, Colorado, USA, plague epizootic events are episodic and occur in black-tailed prairie dogs. Enzootic hosts are unidentified as are plague foci. For three years, we systematically sampled carnivores in two distinct habitat types to determine whether carnivores may play a role in maintenance or transmission of Y. pestis and to identify habitats associated with increased plague prevalence. We sampled 83 individuals representing six carnivore species and found only two that had been exposed to Y. pestis. The low overall rate of plague exposure in carnivores suggests that plague may be ephemeral in this study system, and thus we cannot draw any conclusions regarding habitat-associated plague foci or temporal changes in plague activity. Plague epizootics involving prairie dogs were confirmed in this study system during two of the three years of this study, and we therefore suggest that the targeting carnivores to survey for plague may not be appropriate in all ecological systems.

  8. Avian Hepatitis E Virus Infection in Organic Layers.

    Science.gov (United States)

    Crespo, Rocio; Opriessnig, Tanja; Uzal, Francisco; Gerber, Priscilla F

    2015-09-01

    Between 2012 and 2014, 141 chickens from 10 organic layer flocks with a history of severe drop in egg production (up to 40%) and slight increased mortality (up to 1% per week) were submitted to the Avian Health and Food Safety Laboratory (Puyallup, WA). At necropsy, the most common finding was pinpoint white foci on the liver and regressed ova without any other remarkable lesions. Histologically, there was multifocal mild-to-severe acute necrotizing hepatitis present. No significant bacteria were recovered from liver samples, and tests for mycotoxins were negative. Twenty-six serum samples from four affected flocks tested were positive for avian hepatitis E virus (HEV) immunoglobulin Y antibodies. Avian HEV RNA was detected in 10 livers of chickens from two different affected flocks. The avian HEV was characterized by sequencing and determined to belong to genotype 2. The diagnosis of a clinical manifest HEV was based solely on the demonstration of specific viral RNA and the absence of other causative agents in samples from flocks, as the clinical sings and pathologic lesions were atypical.

  9. Estimating Risks of Inapparent Avian Exposure for Human Infection: Avian Influenza Virus A (H7N9) in Zhejiang Province, China

    Science.gov (United States)

    Ge, Erjia; Zhang, Renjie; Li, Dengkui; Wei, Xiaolin; Wang, Xiaomeng; Lai, Poh-Chin

    2017-01-01

    Inapparent avian exposure was suspected for the sporadic infection of avian influenza A(H7N9) occurring in China. This type of exposure is usually unnoticed and difficult to model and measure. Infected poultry with avian influenza H7N9 virus typically remains asymptomatic, which may facilitate infection through inapparent poultry/bird exposure, especially in a country with widespread practice of backyard poultry. The present study proposed a novel approach that integrated ecological and case-control methods to quantify the risk of inapparent avian exposure on human H7N9 infection. Significant associations of the infection with chicken and goose densities, but not with duck density, were identified after adjusting for spatial clustering effects of the H7N9 cases across multiple geographic scales of neighborhood, community, district and city levels. These exposure risks varied geographically in association with proximity to rivers and lakes that were also proxies for inapparent exposure to avian-related environment. Males, elderly people, and farmers were high-risk subgroups for the virus infection. These findings enable health officials to target educational programs and awareness training in specific locations to reduce the risks of inapparent exposure. PMID:28054599

  10. Clinical characteristics of human infection with a novel avian-origin influenza A(H10N8) virus

    Institute of Scientific and Technical Information of China (English)

    Zhang Wei; Wan Jianguo; Qian Kejian; Liu Xiaoqing; Xiao Zuke; Sun Jian; Zeng Zhenguo

    2014-01-01

    Background Novel influenza A viruses of avian-origin may be the precursors of pandemic strains.This descriptive study aims to introduce a novel avian-origin influenza A (H10N8) virus which can infect humans and cause severe diseases.Methods Collecting clinical data of three cases of human infection with a novel reassortment avian influenza A (H10N8)virus in Nanchang,Jiangxi Province,China.Results Three cases of human infection with a new reassortment avian influenza A(H10N8) virus were described,of which two were fatal cases,and one was severe case.These cases presented with severe pneumonia that progressed to acute respiratory distress syndrome (ARDS) and intractable respiratory failure.Conclusion This novel reassortment avian influenza A (H10N8) virus in China resulted in fatal human infections,and should be added to concerns in clinical practice.

  11. Subclinical avian influenza A(H5N1) virus infection in human, Vietnam.

    Science.gov (United States)

    Le, Mai Quynh; Horby, Peter; Fox, Annette; Nguyen, Hien Tran; Le Nguyen, Hang Khanh; Hoang, Phuong Mai Vu; Nguyen, Khanh Cong; de Jong, Menno D; Jeeninga, Rienk E; Rogier van Doorn, H; Farrar, Jeremy; Wertheim, Heiman F L

    2013-10-01

    Laboratory-confirmed cases of subclinical infection with avian influenza A(H5N1) virus in humans are rare, and the true number of these cases is unknown. We describe the identification of a laboratory-confirmed subclinical case in a woman during an influenza A(H5N1) contact investigation in northern Vietnam.

  12. Avian influenza (H7N9) virus infection in Chinese tourist in Malaysia, 2014.

    Science.gov (United States)

    William, Timothy; Thevarajah, Bharathan; Lee, Shiu Fee; Suleiman, Maria; Jeffree, Mohamad Saffree; Menon, Jayaram; Saat, Zainah; Thayan, Ravindran; Tambyah, Paul Anantharajah; Yeo, Tsin Wen

    2015-01-01

    Of the ≈400 cases of avian influenza (H7N9) diagnosed in China since 2003, the only travel-related cases have been in Hong Kong and Taiwan. Detection of a case in a Chinese tourist in Sabah, Malaysia, highlights the ease with which emerging viral respiratory infections can travel globally.

  13. Brazilian avian metapneumovirus subtypes A and B: experimental infection of broilers and evaluation of vaccine efficacy

    OpenAIRE

    dos Santos, Marcia B.; Matheus C. Martini; Ferreira, Helena L.; Luciana H.A. da Silva; Paulo A. Fellipe; Spilki,Fernando R.; Arns, Clarice W.

    2012-01-01

    Santos M.B., Martini M.C., Ferreira H.L., Silva L.H.A., Fellipe P.A., Spilki F.R. & Arns C.W. 2012. Brazilian avian metapneumovirus subtypes A and B: experimental infection of broilers and evaluation of vaccine efficacy. Pesquisa Veterinaria Brasileira 32(12):1257-1262. Laboratorio de Virologia, Instituto de Biologia, Universidade Estadual de Campinas, Rua Monteiro Lobato s/n, Cx. Postal 6109, Campinas, SP 13083-970, Brazil. E-mail: Avian metapneumovirus (aMPV) is a respirator...

  14. Transcription factor regulation and cytokine expression following in vitro infection of primary chicken cell culture with low pathogenic avian influenza virus

    Science.gov (United States)

    Avian influenza virus (AIV) induced proinflammatory cytokine expression is believed to contribute to the disease pathogenesis following infection. However, there is limited information on the avian immune response to infection with low pathogenic avian influenza virus (LPAIV). To gain a better under...

  15. Angiotensin-converting enzyme 2 protects from lethal avian influenza A H5N1 infections.

    Science.gov (United States)

    Zou, Zhen; Yan, Yiwu; Shu, Yuelong; Gao, Rongbao; Sun, Yang; Li, Xiao; Ju, Xiangwu; Liang, Zhu; Liu, Qiang; Zhao, Yan; Guo, Feng; Bai, Tian; Han, Zongsheng; Zhu, Jindong; Zhou, Huandi; Huang, Fengming; Li, Chang; Lu, Huijun; Li, Ning; Li, Dangsheng; Jin, Ningyi; Penninger, Josef M; Jiang, Chengyu

    2014-05-06

    The potential for avian influenza H5N1 outbreaks has increased in recent years. Thus, it is paramount to develop novel strategies to alleviate death rates. Here we show that avian influenza A H5N1-infected patients exhibit markedly increased serum levels of angiotensin II. High serum levels of angiotensin II appear to be linked to the severity and lethality of infection, at least in some patients. In experimental mouse models, infection with highly pathogenic avian influenza A H5N1 virus results in downregulation of angiotensin-converting enzyme 2 (ACE2) expression in the lung and increased serum angiotensin II levels. Genetic inactivation of ACE2 causes severe lung injury in H5N1-challenged mice, confirming a role of ACE2 in H5N1-induced lung pathologies. Administration of recombinant human ACE2 ameliorates avian influenza H5N1 virus-induced lung injury in mice. Our data link H5N1 virus-induced acute lung failure to ACE2 and provide a potential treatment strategy to address future flu pandemics.

  16. Comparative Analyses of Transcriptional Profiles in Mouse Organs Using a Pneumonic Plague Model after Infection with Wild-Type Yersinia pestis CO92 and Its Braun Lipoprotein Mutant

    Directory of Open Access Journals (Sweden)

    Cristi L. Galindo

    2009-01-01

    Full Text Available We employed Murine GeneChips to delineate the global transcriptional profiles of the livers, lungs, and spleens in a mouse pneumonic plague infection model with wild-type (WT Y. pestis CO92 and its Braun lipoprotein (Δlpp mutant with reduced virulence. These organs showed differential transcriptional responses to infection with WT Y. pestis, but the overall host functional processes affected were similar across all three tissues. Gene expression alterations were found in inflammation, cytokine signaling, and apoptotic cell death-associated genes. Comparison of WT and Δlpp mutant-infected mice indicated significant overlap in lipopolysaccharide- (LPS- associated gene expression, but the absence of Lpp perturbed host cell signaling at critical regulatory junctions resulting in altered immune response and possibly host cell apoptosis. We generated a putative signaling pathway including major inflammatory components that could account for the synergistic action of LPS and Lpp and provided the mechanistic basis of attenuation caused by deletion of the lpp gene from Y. pestis in a mouse model of pneumonic plague.

  17. [Monitoring the Microtus fuscus plague epidemic in Sichuan province during 2000 - 2008.

    DEFF Research Database (Denmark)

    Wang, Li-Mao; Song, Xiao-Yu; Zhu, Xiao-Ping

    2009-01-01

    OBJECTIVE: To analyze the epidemic tendency of Microtus fuscus plague during 2000 - 2008 in Sichuan province. METHODS: To investigate the plague each year according to "overall Plan of the Plague in the Whole Nation" and "Surveillance Program of Sichuan Province Plague". RESULTS: There were plague...... of fleas, Callopsylla sparsilis, Amphipsylla tutua tutua and Rhadinopsylla dahurica vicina, with the overall infection rate as 0.054%. CONCLUSION: Plague among Microtus fuscus showed a continuous epidemic in Sichuan province during 2000 - 2008....

  18. Avian Plasmodium infection in field-collected mosquitoes during 2012-2013 in Tarlac, Philippines.

    Science.gov (United States)

    Chen, Tien-Huang; Aure, Wilfredo E; Cruz, Estrella Irlandez; Malbas, Fedelino F; Teng, Hwa-Jen; Lu, Liang-Chen; Kim, Kyeong Soon; Tsuda, Yoshio; Shu, Pei-Yun

    2015-12-01

    Global warming threatens to increase the spread and prevalence of mosquito-transmitted diseases. Certain pathogens may be carried by migratory birds and transmitted to local mosquito populations. Mosquitoes were collected in the northern Philippines during bird migration seasons to detect avian malaria parasites as well as for the identification of potential vector species and the estimation of infections among local mosquito populations. We used the nested PCR to detect the avian malaria species. Culex vishnui (47.6%) was the most abundant species collected and Cx. tritaeniorhynchus (13.8%) was the second most abundant. Avian Plasmodium parasites were found in eight mosquito species, for which the infection rates were between 0.5% and 6.2%. The six Plasmodium genetic lineages found in this study included P. juxtanucleare -GALLUS02, Tacy7 (Donana04), CXBIT01, Plasmodium species LIN2 New Zealand, and two unclassified lineages. The potential mosquito vectors for avian Plasmodium parasites in the Philippines were Cq. crassipes, Cx. fuscocephala, Cx. quinquefasciatus, Cx. sitiens, Cx. vishnui, and Ma. Uniformis; two major genetic lineages, P. juxtanucleare and Tacy7, were identified.

  19. Genomic sequences of human infection of avian-origin influenza A(H7N9) virus in Zhejiang province

    Institute of Scientific and Technical Information of China (English)

    陈寅

    2013-01-01

    Objective To analyze the etiology and genomic sequences of human infection of avian-origin influenza A (H7N9) virus from Zhejiang province.Methods Viral RNA was extracted from patients of suspected H7N9

  20. Plague metapopulation dynamics in a natural reservoir

    DEFF Research Database (Denmark)

    Davis, S; Klassovskiy, N; Ageyev, V

    2007-01-01

    The ecology of plague (Yersinia pestis infection) in its ancient foci in Central Asia remains poorly understood. We present field data from two sites in Kazakhstan where the great gerbil (Rhombomys opimus) is the major natural host. Family groups inhabit and defend burrow systems spaced throughout...... the landscape, such that the host population may be considered a metapopulation, with each occupied burrow system a subpopulation. We examine plague transmission within and between family groups and its effect on survival. Transmission of plague occurred disproportionately within family groups although not all...... gerbils became infected once plague entered a burrow system. There were no spatial patterns to suggest that family groups in close proximity to infected burrow systems were more at risk of infection than those far away. At one site, infection increased the chances of burrow-system extinction. Overall...

  1. The chicken as a natural model for extraintestinal infections caused by avian pathogenic Escherichia coli (APEC).

    Science.gov (United States)

    Antão, Esther-Maria; Glodde, Susanne; Li, Ganwu; Sharifi, Reza; Homeier, Timo; Laturnus, Claudia; Diehl, Ines; Bethe, Astrid; Philipp, Hans-C; Preisinger, Rudolf; Wieler, Lothar H; Ewers, Christa

    2008-01-01

    E. coli infections in avian species have become an economic threat to the poultry industry worldwide. Several factors have been associated with the virulence of E. coli in avian hosts, but no specific virulence gene has been identified as being entirely responsible for the pathogenicity of avian pathogenic E. coli (APEC). Needless to say, the chicken would serve as the best model organism for unravelling the pathogenic mechanisms of APEC, an extraintestinal pathogen. Five-week-old white leghorn SPF chickens were infected intra-tracheally with a well characterized APEC field strain IMT5155 (O2:K1:H5) using different doses corresponding to the respective models of infection established, that is, the lung colonization model allowing re-isolation of bacteria only from the lung but not from other internal organs, and the systemic infection model. These two models represent the crucial steps in the pathogenesis of APEC infections, including the colonization of the lung epithelium and the spread of bacteria throughout the bloodstream. The read-out system includes a clinical score, pathomorphological changes and bacterial load determination. The lung colonization model has been established and described for the first time in this study, in addition to a comprehensive account of a systemic infection model which enables the study of severe extraintestinal pathogenic E. coli (ExPEC) infections. These in vivo models enable the application of various molecular approaches to study host-pathogen interactions more closely. The most important application of such genetic manipulation techniques is the identification of genes required for extraintestinal virulence, as well as host genes involved in immunity in vivo. The knowledge obtained from these studies serves the dual purpose of shedding light on the nature of virulence itself, as well as providing a route for rational attenuation of the pathogen for vaccine construction, a measure by which extraintestinal infections, including

  2. Nursing Care Given to the Plague Infected Patients in the Hospital General of Madrid (Spain in the 17th Century.

    Directory of Open Access Journals (Sweden)

    Manuel Jesús García Martínez

    2016-12-01

    Full Text Available This study reveals the work developed by the nurses of the Hospital general of Madrid (Spain in the treatment of the plague, and the training they received for their welfare tasks in the 17th century. Since the end of the 16th century, nurses knew and implemented a set of techniques and medicines to alleviate the terrible disease of the plague and, despite the scarce knowledge about the disease existing at the time, they sought to prevent the contagion with hygienic and dietary measures, and physical isolation. This study shows through which actions and in which conditions nurses worked to deal with such a terrible disease. All this helps to get a full knowledge of the development of the work done by nurses in the last five centuries and, therefore, to determine the evolution and shaping of the nursing profession in our country.

  3. Expression of Immune-Related Genes of Ducks Infected with Avian Pathogenic Escherichia coli (APEC

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    Rong eLi

    2016-05-01

    Full Text Available Avian pathogenic Escherichia coli (APEC can cause severe disease in ducks, characterized by perihepatitis, pericarditis and airsacculitis. Although the studies of bacteria isolation and methods of detection have been reported, host immune responses to APEC infection remain unclear. In response, we systemically examined the expression of immune-related genes and bacteria distribution in APEC-infected ducks. Results demonstrated that APEC can quickly replicate in the liver, spleen and brain, with the highest bacteria content at 2 day post infection. The expression of Toll-like receptors (TLRs, avian β-defensins (AvBDs and major histocompatibility complex (MHC were tested in the liver, spleen and brain of infected ducks. TLR2, TLR4, TLR5 and TLR15 showed different expression patterns, which indicated that they all responded to APEC infection. The expression of AvBD2 was upregulated in all tested tissues during the 3 days of testing, whereas the expression of AvBD4, AvBD5, AvBD7 and AvBD9 were downregulated, and though MHC-I was upregulated on all test days, MHC-II was dramatically downregulated. Overall, our results suggest that APEC can replicate in various tissues in a short time, and the activation of host immune responses begins at onset of infection. These findings thus clarify duck immune responses to APEC infection and offer insights into its pathogenesis.

  4. Efficacy of avian pneumovirus vaccines against an avian pneumovirus/Escherichia coli O2:K1 dual infection in turkeys.

    Science.gov (United States)

    Van de Zande, S; Nauwynck, H; Pensaert, M

    2002-03-16

    The clinical, pathological and microbiological outcome of a challenge with avian pneumovirus (APV) and Escherichia coli O2:K1 was evaluated in turkeys vaccinated with an attenuated APV vaccine and with or without maternally derived antibodies. Two groups of two-week-old poults, one with and one without maternally derived antibodies against APV, were vaccinated oculonasally with attenuated APV subtype A or B. A third group remained unvaccinated. Eleven weeks later, the turkeys were inoculated intranasally with either virulent APV subtype A, or E. coli O2:K1, or with both agents three days apart. After the dual infection, birds vaccinated with attenuated subtype A or B, and with or without maternally derived antibodies, had lower mean clinical scores than the unvaccinated birds. In the vaccinated birds, virus replication was significantly reduced and no bacteria were isolated, except from the birds vaccinated with attenuated subtype B. In the unvaccinated turkeys, large numbers of E. coli O2:K1 were isolated from the turbinates of the dually infected birds between one-and-a-half and seven days after they were inoculated.

  5. Frequently Asked Questions (FAQ) about Plague

    Science.gov (United States)

    ... Specific Hazards Bioterrorism A-Z Anthrax (Bacillus anthracis) Arenaviruses Treatment & Infection Control Specimen Submission & Lab Testing Education & ... hemorrhagic fevers (filoviruses [e.g., Ebola, Marburg] and arenaviruses [e.g., Lassa, Machupo]) Yersinia pestis (plague) Fact ...

  6. In ovo and in vitro susceptibility of American alligators (Alligator mississippiensis) to avian influenza virus infection.

    Science.gov (United States)

    Temple, Bradley L; Finger, John W; Jones, Cheryl A; Gabbard, Jon D; Jelesijevic, Tomislav; Uhl, Elizabeth W; Hogan, Robert J; Glenn, Travis C; Tompkins, S Mark

    2015-01-01

    Avian influenza has emerged as one of the most ubiquitous viruses within our biosphere. Wild aquatic birds are believed to be the primary reservoir of all influenza viruses; however, the spillover of H5N1 highly pathogenic avian influenza (HPAI) and the recent swine-origin pandemic H1N1 viruses have sparked increased interest in identifying and understanding which and how many species can be infected. Moreover, novel influenza virus sequences were recently isolated from New World bats. Crocodilians have a slow rate of molecular evolution and are the sister group to birds; thus they are a logical reptilian group to explore susceptibility to influenza virus infection and they provide a link between birds and mammals. A primary American alligator (Alligator mississippiensis) cell line, and embryos, were infected with four, low pathogenic avian influenza (LPAI) strains to assess susceptibility to infection. Embryonated alligator eggs supported virus replication, as evidenced by the influenza virus M gene and infectious virus detected in allantoic fluid and by virus antigen staining in embryo tissues. Primary alligator cells were also inoculated with the LPAI viruses and showed susceptibility based upon antigen staining; however, the requirement for trypsin to support replication in cell culture limited replication. To assess influenza virus replication in culture, primary alligator cells were inoculated with H1N1 human influenza or H5N1 HPAI viruses that replicate independent of trypsin. Both viruses replicated efficiently in culture, even at the 30 C temperature preferred by the alligator cells. This research demonstrates the ability of wild-type influenza viruses to infect and replicate within two crocodilian substrates and suggests the need for further research to assess crocodilians as a species potentially susceptible to influenza virus infection.

  7. Putative human and avian risk factors for avian influenza virus infections in backyard poultry in Egypt.

    Science.gov (United States)

    Sheta, Basma M; Fuller, Trevon L; Larison, Brenda; Njabo, Kevin Y; Ahmed, Ahmed Samy; Harrigan, Ryan; Chasar, Anthony; Abdel Aziz, Soad; Khidr, Abdel-Aziz A; Elbokl, Mohamed M; Habbak, Lotfy Z; Smith, Thomas B

    2014-01-10

    Highly pathogenic influenza A virus subtype H5N1 causes significant poultry mortality in the six countries where it is endemic and can also infect humans. Egypt has reported the third highest number of poultry outbreaks (n=1084) globally. The objective of this cross-sectional study was to identify putative risk factors for H5N1 infections in backyard poultry in 16 villages in Damietta, El Gharbia, Fayoum, and Menofia governorates from 2010-2012. Cloacal and tracheal swabs and serum samples from domestic (n=1242) and wild birds (n=807) were tested for H5N1 via RT-PCR and hemagglutination inhibition, respectively. We measured poultry rearing practices with questionnaires (n=306 households) and contact rates among domestic and wild bird species with scan sampling. Domestic birds (chickens, ducks, and geese, n=51) in three governorates tested positive for H5N1 by PCR or serology. A regression model identified a significant correlation between H5N1 in poultry and the practice of disposing of dead poultry and poultry feces in the garbage (F=15.7, p<0.0001). In addition, contact between domestic and wild birds was more frequent in villages where we detected H5N1 in backyard flocks (F=29.5, p<0.0001).

  8. Identification of one peptide which inhibited infectivity of avian infectious bronchitis virus in vitro

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Purified avian infectious bronchitis virus (IBV) was used to screen a random phage display peptide library. After the fourth panning, 10 positive phages were sequenced and characterized. The phages specifically inhibited IBV infectivity in HeLa cells and blocked IBV haemagglutination. One linear peptide "GSH HRH VHS PFV" from the positive phages with the highest neutralization titer was synthesized and this peptide inhibited IBV infection in HeLa as well. The results may contribute to development of antiviral therapeutics for IBV and studying the determinants for viral and cell interaction.

  9. Diverse uses of feathers with emphasis on diagnosis of avian viral infections and vaccine virus monitoring

    Directory of Open Access Journals (Sweden)

    I Davidson

    2009-09-01

    Full Text Available The large amounts of feathers produced by the poultry industry, that is considered as a waste was explored for possible uses in various industries, such as meals for animals, biofuels, biodegradable plastic materials, combating water pollution and more. That review mentions these uses, but concentrate on the utilization of feathers for the diagnosis of viral infections and for monitoring vaccine viruses in chickens after vaccination. The viral diseases in which diagnosis using nucleic acids extracted from the feather shafts was described are, Marek's disease virus, circoviruses, chicken anemia virus, fowlpox virus, avian retroviruses, avian influenza virus and infectious laryngotracheitis virus. In two cases, of Marek's disease virus and of infectious laryngotracheitis virus, the differentiation of vaccine and wild-type viruses from feather shafts was made possible, thus allowing for monitoring the vaccination efficacy. The present review demonstrates also the stability of DNA viruses in feather shafts, and the possible evaluation of environmental dissemination of pathogens. When viruses are transmitted vertically, like in the cases of the retrovirus REV, a teratogenic effect on the development of feathers of the day-old newly hatched chick might occur in the case of avian influenza and the chicken anemia virus, which might indicate on a viral infection.

  10. Black plague.

    Science.gov (United States)

    Whitfield, L

    1997-01-01

    Many African-Americans are reluctant to participate in clinical trials of any type, citing the Federal government's unethical syphilis experiments in the Tuskegee Study. African-Americans are also more predisposed to choose alternative treatments over mainstream therapies. These attitudes contribute to the rise in infection rates in this population that now accounts for 41 percent of all reported cases. It is essential that African-Americans participate in HIV research at every level.

  11. Avian cathelicidins: paradigms for the development of anti-infectives

    NARCIS (Netherlands)

    van Dijk, A.; Molhoek, E.M.; Bikker, F.J.; Yu, P.L.; Veldhuizen, E.J.A.; Haagsman, H.P.

    2011-01-01

    The broad-spectrum defense system based on host defense peptides (HDPs) is evolutionary very old and many invertebrates rely on this system for protection from bacterial infections. However, in vertebrates the system remained important in spite of the superposition of a very sophisticated adaptive i

  12. Avian cathelicidins: Paradigms for the development of anti-infectives

    NARCIS (Netherlands)

    Dijk, A. van; Molhoek, E.M.; Bikker, F.J.; Yu, P.L.; Veldhuizen, E.J.A.; Haagsman, H.P.

    2011-01-01

    The broad-spectrum defense system based on host defense peptides (HDPs) is evolutionary very old and many invertebrates rely on this system for protection from bacterial infections. However, in vertebrates the system remained important in spite of the superposition of a very sophisticated adaptive i

  13. Hampered foraging and migratory performance in swans infected with low-pathogenic avian influenza A virus.

    Directory of Open Access Journals (Sweden)

    Jan A van Gils

    Full Text Available It is increasingly acknowledged that migratory birds, notably waterfowl, play a critical role in the maintenance and spread of influenza A viruses. In order to elucidate the epidemiology of influenza A viruses in their natural hosts, a better understanding of the pathological effects in these hosts is required. Here we report on the feeding and migratory performance of wild migratory Bewick's swans (Cygnus columbianus bewickii Yarrell naturally infected with low-pathogenic avian influenza (LPAI A viruses of subtypes H6N2 and H6N8. Using information on geolocation data collected from Global Positioning Systems fitted to neck-collars, we show that infected swans experienced delayed migration, leaving their wintering site more than a month after uninfected animals. This was correlated with infected birds travelling shorter distances and fuelling and feeding at reduced rates. The data suggest that LPAI virus infections in wild migratory birds may have higher clinical and ecological impacts than previously recognised.

  14. Avian And Other Zoonotic Influenza

    Science.gov (United States)

    ... files Questions & answers Features Multimedia Contacts Avian and other zoonotic influenza Fact sheet Updated November 2016 Key ... A(H3) subtypes. Clinical features of avian and other zoonotic influenza infections in humans Avian and other ...

  15. Successful treatment of avian-origin influenza A (H7N9 infection using convalescent plasma

    Directory of Open Access Journals (Sweden)

    Xiao-Xin Wu

    2015-12-01

    Full Text Available In January 2015, there was an outbreak of avian-origin influenza A (H7N9 virus in Zhejiang Province, China. A 45-year-old man was admitted to the First Affiliated Hospital of Zhejiang University with a high fever that had lasted 7 days, chills, and a cough with yellow sputum. Laboratory testing confirmed infection with the H7N9 virus, likely obtained from contact with poultry at a local live poultry market. A large dense shadow was apparent in the patient's left lung at the time of admission. Treatment with oseltamivir (75 mg twice daily did not improve the patient's condition. The decision was made to try using convalescent plasma to treat the infection. Convalescent plasma was administered 3 days after the patient was admitted to the hospital and led to a marked improvement. To our knowledge, this is the first report of the successful use of convalescent plasma to treat a case of H7N9 infection in China. These results suggest that the combination of convalescent plasma and antiviral drugs may be effective for the treatment of avian-origin H7N9 infection.

  16. Sustained live poultry market surveillance contributes to early warnings for human infection with avian influenza viruses.

    Science.gov (United States)

    Fang, Shisong; Bai, Tian; Yang, Lei; Wang, Xin; Peng, Bo; Liu, Hui; Geng, Yijie; Zhang, Renli; Ma, Hanwu; Zhu, Wenfei; Wang, Dayan; Cheng, Jinquan; Shu, Yuelong

    2016-08-03

    Sporadic human infections with the highly pathogenic avian influenza (HPAI) A (H5N6) virus have been reported in different provinces in China since April 2014. From June 2015 to January 2016, routine live poultry market (LPM) surveillance was conducted in Shenzhen, Guangdong Province. H5N6 viruses were not detected until November 2015. The H5N6 virus-positive rate increased markedly beginning in December 2015, and viruses were detected in LPMs in all districts of the city. Coincidently, two human cases with histories of poultry exposure developed symptoms and were diagnosed as H5N6-positive in Shenzhen during late December 2015 and early January 2016. Similar viruses were identified in environmental samples collected in the LPMs and the patients. In contrast to previously reported H5N6 viruses, viruses with six internal genes derived from the H9N2 or H7N9 viruses were detected in the present study. The increased H5N6 virus-positive rate in the LPMs and the subsequent human infections demonstrated that sustained LPM surveillance for avian influenza viruses provides an early warning for human infections. Interventions, such as LPM closures, should be immediately implemented to reduce the risk of human infection with the H5N6 virus when the virus is widely detected during LPM surveillance.

  17. Successful treatment of avian-origin influenza A (H7N9) infection using convalescent plasma.

    Science.gov (United States)

    Wu, Xiao-Xin; Gao, Hai-Nv; Wu, Hai-Bo; Peng, Xiu-Ming; Ou, Hui-Lin; Li, Lan-Juan

    2015-12-01

    In January 2015, there was an outbreak of avian-origin influenza A (H7N9) virus in Zhejiang Province, China. A 45-year-old man was admitted to the First Affiliated Hospital of Zhejiang University with a high fever that had lasted 7 days, chills, and a cough with yellow sputum. Laboratory testing confirmed infection with the H7N9 virus, likely obtained from contact with poultry at a local live poultry market. A large dense shadow was apparent in the patient's left lung at the time of admission. Treatment with oseltamivir (75mg twice daily) did not improve the patient's condition. The decision was made to try using convalescent plasma to treat the infection. Convalescent plasma was administered 3 days after the patient was admitted to the hospital and led to a marked improvement. To our knowledge, this is the first report of the successful use of convalescent plasma to treat a case of H7N9 infection in China. These results suggest that the combination of convalescent plasma and antiviral drugs may be effective for the treatment of avian-origin H7N9 infection.

  18. Egg whites from eggs of chickens infected experimentally with avian hepatitis E virus contain infectious virus, but evidence of complete vertical transmission is lacking.

    Science.gov (United States)

    Guo, H; Zhou, E M; Sun, Z F; Meng, X-J

    2007-05-01

    Avian hepatitis E virus (HEV) is genetically and antigenically related to human HEV. Vertical transmission of HEV has been reported in humans, but not in other animals. In this study, we showed that avian HEV could be detected in chicken egg-white samples. Subsequently, avian HEV in egg white was found to be infectious, as evidenced by the appearance of viraemia, faecal virus shedding and seroconversion in chickens inoculated with avian HEV-positive egg white, but not in chickens inoculated with HEV-negative egg white. To further assess the possibility of vertical transmission of avian HEV, batches of embryonated eggs from infected hens were hatched, and hatched chicks were monitored for evidence of avian HEV infection. However, no virus was detected in samples collected from the hatched chicks throughout this study, suggesting that avian HEV could not complete the vertical transmission cycle. The possible implications of our findings are also discussed.

  19. Range-wide determinants of plague distribution in North America.

    Science.gov (United States)

    Maher, Sean P; Ellis, Christine; Gage, Kenneth L; Enscore, Russell E; Peterson, A Townsend

    2010-10-01

    Plague, caused by the bacterium Yersinia pestis, is established across western North America, and yet little is known of what determines the broad-scale dimensions of its overall range. We tested whether its North American distribution represents a composite of individual host-plague associations (the "Host Niche Hypothesis"), or whether mammal hosts become infected only at sites overlapping ecological conditions appropriate for plague transmission and maintenance (the "Plague Niche Hypothesis"). We took advantage of a novel data set summarizing plague records in wild mammals newly digitized from paper-based records at the Centers for Disease Control and Prevention to develop range-wide tests of ecological niche similarity between mammal host niches and plague-infected host niches. Results indicate that plague infections occur under circumstances distinct from the broader ecological distribution of hosts, and that plague-infected niches are similar among hosts; hence, evidence coincides with the predictions of the Plague Niche Hypothesis, and contrasts with those of the Host Niche Hypothesis. The "plague niche" is likely driven by ecological requirements of vector flea species.

  20. Spatial assessment of the potential risk of avian influenza A virus infection in three raptor species in Japan

    Science.gov (United States)

    MORIGUCHI, Sachiko; ONUMA, Manabu; GOKA, Koichi

    2016-01-01

    Avian influenza A, a highly pathogenic avian influenza, is a lethal infection in certain species of wild birds, including some endangered species. Raptors are susceptible to avian influenza, and spatial risk assessment of such species may be valuable for conservation planning. We used the maximum entropy approach to generate potential distribution models of three raptor species from presence-only data for the mountain hawk-eagle Nisaetus nipalensis, northern goshawk Accipiter gentilis and peregrine falcon Falco peregrinus, surveyed during the winter from 1996 to 2001. These potential distribution maps for raptors were superimposed on avian influenza A risk maps of Japan, created from data on incidence of the virus in wild birds throughout Japan from October 2010 to March 2011. The avian influenza A risk map for the mountain hawk-eagle showed that most regions of Japan had a low risk for avian influenza A. In contrast, the maps for the northern goshawk and peregrine falcon showed that their high-risk areas were distributed on the plains along the Sea of Japan and Pacific coast. We recommend enhanced surveillance for each raptor species in high-risk areas and immediate establishment of inspection systems. At the same time, ecological risk assessments that determine factors, such as the composition of prey species, and differential sensitivity of avian influenza A virus between bird species should provide multifaceted insights into the total risk assessment of endangered species. PMID:26972333

  1. Spatial assessment of the potential risk of avian influenza A virus infection in three raptor species in Japan.

    Science.gov (United States)

    Moriguchi, Sachiko; Onuma, Manabu; Goka, Koichi

    2016-08-01

    Avian influenza A, a highly pathogenic avian influenza, is a lethal infection in certain species of wild birds, including some endangered species. Raptors are susceptible to avian influenza, and spatial risk assessment of such species may be valuable for conservation planning. We used the maximum entropy approach to generate potential distribution models of three raptor species from presence-only data for the mountain hawk-eagle Nisaetus nipalensis, northern goshawk Accipiter gentilis and peregrine falcon Falco peregrinus, surveyed during the winter from 1996 to 2001. These potential distribution maps for raptors were superimposed on avian influenza A risk maps of Japan, created from data on incidence of the virus in wild birds throughout Japan from October 2010 to March 2011. The avian influenza A risk map for the mountain hawk-eagle showed that most regions of Japan had a low risk for avian influenza A. In contrast, the maps for the northern goshawk and peregrine falcon showed that their high-risk areas were distributed on the plains along the Sea of Japan and Pacific coast. We recommend enhanced surveillance for each raptor species in high-risk areas and immediate establishment of inspection systems. At the same time, ecological risk assessments that determine factors, such as the composition of prey species, and differential sensitivity of avian influenza A virus between bird species should provide multifaceted insights into the total risk assessment of endangered species.

  2. Prospective study of avian influenza virus infections among rural Thai villagers.

    Directory of Open Access Journals (Sweden)

    Whitney S Krueger

    Full Text Available BACKGROUND: In 2008, 800 rural Thai adults living within Kamphaeng Phet Province were enrolled in a prospective cohort study of zoonotic influenza transmission. Serological analyses of enrollment sera suggested this cohort had experienced subclinical avian influenza virus (AIV infections with H9N2 and H5N1 viruses. METHODS: After enrollment, participants were contacted weekly for 24 mos for acute influenza-like illnesses (ILI. Cohort members confirmed to have influenza A infections were enrolled with their household contacts in a family transmission study involving paired sera and respiratory swab collections. Cohort members also provided sera at 12 and 24 months after enrollment. Serologic and real-time RT-PCR assays were performed against avian, swine, and human influenza viruses. RESULTS: Over the 2 yrs of follow-up, 81 ILI investigations in the cohort were conducted; 31 (38% were identified as influenza A infections by qRT-PCR. Eighty-three household contacts were enrolled; 12 (14% reported ILIs, and 11 (92% of those were identified as influenza infections. A number of subjects were found to have slightly elevated antibodies against avian-like A/Hong Kong/1073/1999(H9N2 virus: 21 subjects (2.7% at 12-months and 40 subjects (5.1% at 24-months. Among these, two largely asymptomatic acute infections with H9N2 virus were detected by >4-fold increases in annual serologic titers (final titers 1:80. While controlling for age and influenza vaccine receipt, moderate poultry exposure was significantly associated with elevated H9N2 titers (adjusted OR = 2.3; 95% CI, 1.04-5.2 at the 24-month encounter. One subject had an elevated titer (1:20 against H5N1 during follow-up. CONCLUSIONS: From 2008-10, evidence for AIV infections was sparse among this rural population. Subclinical H9N2 AIV infections likely occurred, but serological results were confounded by antibody cross-reactions. There is a critical need for improved serological diagnostics to more

  3. Avian Adenoviruses Infections with Special Attention to Inclusion Body Hepatitis/ Hydropericardium Syndrome and Egg Drop Syndrome

    Directory of Open Access Journals (Sweden)

    Hafez Mohamed Hafez*

    2011-04-01

    Full Text Available The first avian adenovirus (AAV associated with clinical disease was isolated from an outbreak of respiratory disease in quail in 1950 (Olson, 1950. Since that time, AAVs have been found in all types and breeds of chickens and from a variety of other avian species. The infections may be asymptomatic or associated with several clinical and pathological conditions. Vertical transmission via the egg is the most common way of transmission. Also horizontal transmission through faeces, contaminated egg trays, crates and trucks play a role in the infection route. Studies have demonstrated the presence of antibodies in healthy poultry, and viruses have been isolated from normal birds. Avian adenoviruses in chickens are the etiological agents of 2 diseases known as inclusion body hepatitis (IBH and hydropericardium syndrome (HP. In some cases each condition is observed separately, however, recently the 2 conditions have frequently been observed as a single entity; therefore, the name hepatitis hydropericardium has been widely used to describe the pathologic condition. The syndrome is an acute disease of young chickens associated with anemia, haemorrhagic disorders, hydropericardium and high mortality. Egg-Drop-Syndrome (EDS is caused also by an adenovirus. The disease is characterised by a severe drop in egg production as well as the production of shell-less, thin-shelled, discoloured or misshapen eggs in apparently healthy birds. Ducks and geese are the natural host of the EDS virus. It was first described in chickens in the 1970s and spread to several countries world wide. The birds usually do not show any other signs of disease, and mortality is not expected. There is no specific treatment of the AAV infections. Active immunization by vaccination using an inactivated is wide spread.

  4. Evidence for subclinical H5N1 avian influenza infections among Nigerian poultry workers.

    Science.gov (United States)

    Okoye, John O; Eze, Didacus C; Krueger, Whitney S; Heil, Gary L; White, Sarah K; Merrill, Hunter R; Gray, Gregory C

    2014-12-01

    In recent years Nigeria has experienced sporadic incursions of highly pathogenic H5N1 avian influenza among poultry. In 2008, 316 poultry-exposed agricultural workers, and 54 age-group matched non-poultry exposed adults living in the Enugu or Ebonyi States of Nigeria were enrolled and then contacted monthly for 24 months to identify acute influenza-like-illnesses. Annual follow-up sera and questionnaire data were collected at 12 and 24 months. Participants reporting influenza-like illness completed additional questionnaires, and provided nasal and pharyngeal swabs and acute and convalescent sera. Swab and sera specimens were studied for evidence of influenza A virus infection. Sera were examined for elevated antibodies against 12 avian influenza viruses by microneutralization and 3 human viruses by hemagglutination inhibition. Four (3.2%) of the 124 acute influenza-like-illness investigations yielded molecular evidence of influenza, but virus could not be cultured. Serial serum samples from five poultry-exposed subjects had a ≥4-fold change in microneutralization titers against A/CK/Nigeria/07/1132123(H5N1), with three of those having titers ≥1:80 (maximum 1:1,280). Three of the five subjects (60%) reported a preceding influenza-like illness. Hemagglutination inhibition titers were ≥4-fold increases against one of the human viruses in 260 participants. While cross-reactivity from antibodies against other influenza viruses cannot be ruled out as a partial confounder, over the course of the 2-year follow-up, at least 3 of 316 (0.9%) poultry-exposed subjects had evidence for subclinical HPAI H5N1 infections. If these data represent true infections, it seems imperative to increase monitoring for avian influenza among Nigeria's poultry and poultry workers.

  5. Avian leukosis virus subgroup A and B infection in wild birds of Northeast China.

    Science.gov (United States)

    Li, Delong; Qin, Liting; Gao, Honglei; Yang, Bo; Liu, Wansi; Qi, Xiaole; Wang, Yongqiang; Zeng, Xiangwei; Liu, Sidang; Wang, Xiaomei; Gao, Yulong

    2013-05-03

    To analyze the status of wild birds infected with avian leukosis virus (ALV) in China, we collected 300 wild birds from various areas. Virus isolation and PCR showed that wild birds were infected by ALV-A and ALV-B. Two ALV-A and 4 ALV-B env sequences were obtained by PCR using primers designed to detect ALV-A and -B respectively. Our results showed that the gp85 genes of the 2 ALV-A strains have the highest homology with RAV-1, 99.8%, and more than 92% homology with other American strains. However, the gp85 genes of the two ALV-A strains showed slightly lower homology with Chinese strains (87.2-92.6%). Additionally, the 4 ALV-B strains have high homology with the prototype strain (RAV-2), from 99.1 to 99.4%, but they have slightly lower identity with Schmidt-Ruppin B and Prague subgroup B, from 93.3 to 98.4%. The 4 ALV-B strains showed the lowest identity with SDAU09C2 and SDAU09E3 (90%). In total, these results suggested that avian leukosis virus has infected wild birds in China.

  6. [Isolation and identification of avian leukosis virus-B from layer chickens infected with avian leukosis virus-J].

    Science.gov (United States)

    Liu, Gong-Zhen; Zhang, Hong-Hai; Liu, Qing; Qiu, Bo; Wang, Feng; Wang, Xiao-Wei; Chen, Hong-Bo; Cheng, Zi-Qiang

    2009-11-01

    Two strains of Avian leukosis virus subgroup B (ALV-B) were isolated for the first time in China Hy-line White on the cultured DF-1 cells which were inoculated tissue samples from by an ELISA assay, a histopathology examination and a PCR-based diagnosis. The results from the ELISA assay indicated that the positive rate of serum antibodies to ALV-B and ALV-J virus were 16.3% (15/92) and 13% (12/92), respectively. The histopathological examination indicated that two types of tumor cells existed at same focus in liver and spleen, which mainly were myelocytoma cells and lymphosarcoma cells. The PCR-based diagnosis were performed as follows: the cellular DNA was extracted from the inoculated DF-1 cells; the specific fragments of 1100 bp and 924 bp were obtained by a PCR system with the diagnostic primers of ALV-B and ALV-J; and the PCR results for ALV-A, MDV and REV were all negative. Then, the amplified fragments of the two ALV-B stains were partially sequenced and shown an identity of 92.8%,94.7% with the prototype strain of ALV-B (RSV Schmidt-ruppin B). The identities of two ALV-J strains with the prototype strain HPRS-103 at 96.9%, 91.5%; The identities of two ALV-J strains with the American prototype strain at 85.9%, 81.5%. Our study had shown that ALV-B was isolated for the first time from the ALV-J infected commercial layer flocks in China. It also indicated that the chance of genetic recombination among various subgroups of ALV was increased.

  7. Distribution of sialic acid receptors and influenza A viruses of avian and swine origin and in experimentally infected pigs

    DEFF Research Database (Denmark)

    Trebbien, Ramona; Larsen, Lars Erik; Viuff, Birgitte M.

    2011-01-01

    Background: Pigs are considered susceptible to influenza A virus infections from different host origins because earlier studies have shown that they have receptors for both avian (sialic acid-alpha-2,3-terminal saccharides (SAalpha- 2,3)) and swine/human (SA-alpha-2,6) influenza viruses...... in the upper respiratory tract. Furthermore, experimental and natural infections in pigs have been reported with influenza A virus from avian and human sources. Methods: This study investigated the receptor distribution in the entire respiratory tract of pigs using specific lectins Maackia Amurensis (MAA) I......, and II, and Sambucus Nigra (SNA). Furthermore, the predilection sites of swine influenza virus (SIV) subtypes H1N1 and H1N2 as well as avian influenza virus (AIV) subtype H4N6 were investigated in the respiratory tract of experimentally infected pigs using immunohistochemical methods. Results: SIV...

  8. Experimental infection of hamsters with avian paramyxovirus serotypes 1 to 9

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    Samuel Arthur S

    2011-02-01

    Full Text Available Abstract Avian paramyxoviruses (APMVs are frequently isolated from domestic and wild birds throughout the world and are separated into nine serotypes (APMV-1 to -9. Only in the case of APMV-1, the infection of non-avian species has been investigated. The APMVs presently are being considered as human vaccine vectors. In this study, we evaluated the replication and pathogenicity of all nine APMV serotypes in hamsters. The hamsters were inoculated intranasally with each virus and monitored for clinical disease, pathology, histopathology, virus replication, and seroconversion. On the basis of one or more of these criteria, each of the APMV serotypes was found to replicate in hamsters. The APMVs produced mild or inapparent clinical signs in hamsters except for APMV-9, which produced moderate disease. Gross lesions were observed over the pulmonary surface of hamsters infected with APMV-2 & -3, which showed petechial and ecchymotic hemorrhages, respectively. Replication of all of the APMVs except APMV-5 was confirmed in the nasal turbinates and lungs, indicating a tropism for the respiratory tract. Histologically, the infection resulted in lung lesions consistent with bronchointerstitial pneumonia of varying severity and nasal turbinates with blunting or loss of cilia of the epithelium lining the nasal septa. The majority of APMV-infected hamsters exhibited transient histological lesions that self resolved by 14 days post infection (dpi. All of the hamsters infected with the APMVs produced serotype-specific HI or neutralizing antibodies, confirming virus replication. Taken together, these results demonstrate that all nine known APMV serotypes are capable of replicating in hamsters with minimal disease and pathology.

  9. Distribution of sialic acid receptors and influenza A viruses of avian and swine origin and in experimentally infected pigs

    DEFF Research Database (Denmark)

    Trebbien, Ramona; Larsen, Lars Erik; Viuff, Birgitte M.

    2011-01-01

    Background: Pigs are considered susceptible to influenza A virus infections from different host origins because earlier studies have shown that they have receptors for both avian (sialic acid-alpha-2,3-terminal saccharides (SAalpha- 2,3)) and swine/human (SA-alpha-2,6) influenza viruses in the up......Background: Pigs are considered susceptible to influenza A virus infections from different host origins because earlier studies have shown that they have receptors for both avian (sialic acid-alpha-2,3-terminal saccharides (SAalpha- 2,3)) and swine/human (SA-alpha-2,6) influenza viruses...

  10. Avian influenza A (H7N9) virus infection in humans: epidemiology, evolution, and pathogenesis.

    Science.gov (United States)

    Husain, Matloob

    2014-12-01

    New human influenza A virus strains regularly emerge causing seasonal epidemics and occasional pandemics. Lately, several zoonotic avian influenza A strains have been reported to directly infect humans. In early 2013, a novel avian influenza A virus (H7N9) strain was discovered in China to cause severe respiratory disease in humans. Since then, over 450 human cases of H7N9 infection have been discovered and 165 of them have died. Multiple epidemiological, phylogenetic, in vivo, and in vitro studies have been done to determine the origin and pathogenesis of novel H7N9 strain. This article reviews the literature related to the epidemiology, evolution, and pathogenesis of the H7N9 strain since its discovery in February 2013 till August 2014. The data available so far indicate that H7N9 was originated by a two-step reassortment process in birds and transmitted to humans through direct contact with live-bird markets. H7N9 is a low-pathogenic avian virus and contains several molecular signatures for adaptation in mammals. The severity of the respiratory disease caused by novel H7N9 virus in humans can be partly attributed to the age, sex, and underlying medical conditions of the patients. A universal influenza vaccine is not available, though several strain-specific H7N9 candidate vaccine viruses have been developed. Further, novel H7N9 virus is resistant to antiviral drug amantadine and some H7N9 isolates have acquired the resistance to neuraminidase-inhibitors. Therefore, constant surveillance and prompt control measures combined with novel research approaches to develop alternative and effective anti-influenza strategies are needed to overcome influenza A virus.

  11. Generation of influenza virus from avian cells infected by Salmonella carrying the viral genome.

    Directory of Open Access Journals (Sweden)

    Xiangmin Zhang

    Full Text Available Domestic poultry serve as intermediates for transmission of influenza A virus from the wild aquatic bird reservoir to humans, resulting in influenza outbreaks in poultry and potential epidemics/pandemics among human beings. To combat emerging avian influenza virus, an inexpensive, heat-stable, and orally administered influenza vaccine would be useful to vaccinate large commercial poultry flocks and even migratory birds. Our hypothesized vaccine is a recombinant attenuated bacterial strain able to mediate production of attenuated influenza virus in vivo to induce protective immunity against influenza. Here we report the feasibility and technical limitations toward such an ideal vaccine based on our exploratory study. Five 8-unit plasmids carrying a chloramphenicol resistance gene or free of an antibiotic resistance marker were constructed. Influenza virus was successfully generated in avian cells transfected by each of the plasmids. The Salmonella carrier was engineered to allow stable maintenance and conditional release of the 8-unit plasmid into the avian cells for recovery of influenza virus. Influenza A virus up to 10⁷ 50% tissue culture infective doses (TCID50/ml were recovered from 11 out of 26 co-cultures of chicken embryonic fibroblasts (CEF and Madin-Darby canine kidney (MDCK cells upon infection by the recombinant Salmonella carrying the 8-unit plasmid. Our data prove that a bacterial carrier can mediate generation of influenza virus by delivering its DNA cargoes into permissive host cells. Although we have made progress in developing this Salmonella influenza virus vaccine delivery system, further improvements are necessary to achieve efficient virus production, especially in vivo.

  12. AVIAN POXVIRUS INFECTION IN A FLAMINGO (PHOENICOPTERUS RUBER) OF THE LISBON ZOO.

    Science.gov (United States)

    Henriques, Ana M; Fagulha, Teresa; Duarte, Margarida; Ramos, Fernanda; Barros, Sílvia C; Luís, Tiago; Bernardino, Rui; Fernandes, Teresa L; Lapão, Narciso; da Silva, José Ferreira; Fevereiro, Miguel

    2016-03-01

    Avian poxviruses (APV) are very large viruses spread worldwide in a variety of hosts. They are responsible for a disease usually referred to as pox, mainly characterized by nodular lesions on feather-free regions of the body. On May 2010, a young American flamingo (Phoenicopterus ruber) of the Lisbon Zoo (Portugal) developed a nodular lesion suggestive of poxvirus infection on its right foot. Avipoxvirus was isolated from the lesion and a fragment of the P4b-encoding gene was amplified by polymerase chain reaction. The nucleotide sequence of the amplicon was determined and analyzed. A close relationship (100% identity) was observed between the flamingo poxvirus and isolates from great bustard (Hungary 2005), house sparrow (Morocco 2009), MacQueen's bustard (Morocco 2011), and Houbara bustard (Morocco 2010 and 2011), suggesting interspecies transmission as a possible source of infection. To strengthen the investigation, the 5' and 3' ends of genes cnpv186 and cnpv 187, respectively, were also analyzed. The cnpv186-187 fragment exhibited 100% identity with MacQueen's bustard and Houbara bustard isolates, both from Morocco 2011. Phylogenetic analyses based in both fragments grouped the flamingo isolate consistently within clade B2 of canarypox. However, the phylogenetic relationships among the different representatives of avian poxviruses were more comprehensive in the tree based on the concatenated coding sequences of the cnpv186-187 fragment, rather than on the P4b-coding gene. The clearer displacement and distribution of the isolates regarding their host species in this last tree suggests the potential usefulness of this genomic region to refine avian poxvirus classification.

  13. Immune reaction and survivability of salmonella typhimurium and salmonella infantis after infection of primary avian macrophages.

    Directory of Open Access Journals (Sweden)

    Maria Braukmann

    Full Text Available Salmonella serovars are differentially able to infect chickens. The underlying causes are not yet fully understood. Aim of the present study was to elucidate the importance of Salmonella Pathogenicity Island 1 and 2 (SPI-1 and -2 for the virulence of two non-host-specific, but in-vivo differently invasive, Salmonella serovars in conjunction with the immune reaction of the host. Primary avian splenic macrophages were inoculated with Salmonella enterica sub-species enterica serovar (S. Typhimurium and S. Infantis. The number and viability of intracellular bacteria and transcription of SPI-1 and -2 genes by the pathogens, as well as transcription of immune-related proteins, surface antigen expression and nitric oxide production by the macrophages, were compared at different times post inoculation. After infection, both of the Salmonella serovars were found inside the primary macrophages. Invasion-associated SPI-1 genes were significantly higher transcribed in S. Infantis- than S. Typhimurium-infected macrophages. The macrophages counteracted the S. Infantis and S. Typhimurium infection with elevated mRNA expression of inducible nitric oxide synthase (iNOS, interleukin (IL-12, IL-18 and lipopolysaccharide-induced tumor necrosis factor alpha factor (LITAF as well as with an increased synthesis of nitric oxide. Despite these host cell attacks, S. Typhimurium was better able than S. Infantis to survive within the macrophages and transcribed higher rates of the SPI-2 genes spiC, ssaV, sifA, and sseA. The results showed similar immune reactions of primary macrophages after infection with both of the Salmonella strains. The more rapid and stronger transcription of SPI-2-related genes by intracellular S. Typhimurium compared to S. Infantis might be responsible for its better survival in avian primary macrophages.

  14. Individual genetic diversity and probability of infection by avian malaria parasites in blue tits (Cyanistes caeruleus).

    Science.gov (United States)

    Ferrer, E S; García-Navas, V; Sanz, J J; Ortego, J

    2014-11-01

    Understanding the importance of host genetic diversity for coping with parasites and infectious diseases is a long-standing goal in evolutionary biology. Here, we study the association between probability of infection by avian malaria (Plasmodium relictum) and individual genetic diversity in three blue tit (Cyanistes caeruleus) populations that strongly differ in prevalence of this parasite. For this purpose, we screened avian malaria infections and genotyped 789 blue tits across 26 microsatellite markers. We used two different arrays of markers: 14 loci classified as neutral and 12 loci classified as putatively functional. We found a significant relationship between probability of infection and host genetic diversity estimated at the subset of neutral markers that was not explained by strong local effects and did not differ among the studied populations. This relationship was not linear, and probability of infection increased up to values of homozygosity by locus (HL) around 0.15, reached a plateau at values of HL from 0.15 to 0.40 and finally declined among a small proportion of highly homozygous individuals (HL > 0.4). We did not find evidence for significant identity disequilibrium, which may have resulted from a low variance of inbreeding in the study populations and/or the small power of our set of markers to detect it. A combination of subtle positive and negative local effects and/or a saturation threshold in the association between probability of infection and host genetic diversity in combination with increased resistance to parasites in highly homozygous individuals may explain the observed negative quadratic relationship. Overall, our study highlights that parasites play an important role in shaping host genetic variation and suggests that the use of large sets of neutral markers may be more appropriate for the study of heterozygosity-fitness correlations.

  15. Immune reaction and survivability of salmonella typhimurium and salmonella infantis after infection of primary avian macrophages.

    Science.gov (United States)

    Braukmann, Maria; Methner, Ulrich; Berndt, Angela

    2015-01-01

    Salmonella serovars are differentially able to infect chickens. The underlying causes are not yet fully understood. Aim of the present study was to elucidate the importance of Salmonella Pathogenicity Island 1 and 2 (SPI-1 and -2) for the virulence of two non-host-specific, but in-vivo differently invasive, Salmonella serovars in conjunction with the immune reaction of the host. Primary avian splenic macrophages were inoculated with Salmonella enterica sub-species enterica serovar (S.) Typhimurium and S. Infantis. The number and viability of intracellular bacteria and transcription of SPI-1 and -2 genes by the pathogens, as well as transcription of immune-related proteins, surface antigen expression and nitric oxide production by the macrophages, were compared at different times post inoculation. After infection, both of the Salmonella serovars were found inside the primary macrophages. Invasion-associated SPI-1 genes were significantly higher transcribed in S. Infantis- than S. Typhimurium-infected macrophages. The macrophages counteracted the S. Infantis and S. Typhimurium infection with elevated mRNA expression of inducible nitric oxide synthase (iNOS), interleukin (IL)-12, IL-18 and lipopolysaccharide-induced tumor necrosis factor alpha factor (LITAF) as well as with an increased synthesis of nitric oxide. Despite these host cell attacks, S. Typhimurium was better able than S. Infantis to survive within the macrophages and transcribed higher rates of the SPI-2 genes spiC, ssaV, sifA, and sseA. The results showed similar immune reactions of primary macrophages after infection with both of the Salmonella strains. The more rapid and stronger transcription of SPI-2-related genes by intracellular S. Typhimurium compared to S. Infantis might be responsible for its better survival in avian primary macrophages.

  16. Taishan Pinus massoniana pollen polysaccharide inhibits subgroup J avian leucosis virus infection by directly blocking virus infection and improving immunity.

    Science.gov (United States)

    Yu, Cuilian; Wei, Kai; Liu, Liping; Yang, Shifa; Hu, Liping; Zhao, Peng; Meng, Xiuyan; Shao, Mingxu; Wang, Chuanwen; Zhu, Lijun; Zhang, Hao; Li, Yang; Zhu, Ruiliang

    2017-03-13

    Subgroup J avian leucosis virus (ALV-J) generally causes neoplastic diseases, immunosuppression and subsequently increases susceptibility to secondary infection in birds. The spread of ALV-J mainly depends on congenital infection and horizontal contact. Although ALV-J infection causes enormous losses yearly in the poultry industry worldwide, effective measures to control ALV-J remain lacking. In this study, we demonstrated that Taishan Pinus massoniana pollen polysaccharide (TPPPS), a natural polysaccharide extracted from Taishan Pinus massoniana pollen, can significantly inhibit ALV-J replication in vitro by blocking viral adsorption to host cells. Electron microscopy and blocking ELISA tests revealed that TPPPS possibly blocks viral adsorption to host cells by interacting with the glycoprotein 85 protein of ALV-J. Furthermore, we artificially established a congenitally ALV-J-infected chicken model to examine the anti-viral effects of TPPPS in vivo. TPPPS significantly inhibited viral shedding and viral loads in immune organs and largely eliminated the immunosuppression caused by congenital ALV-J infection. Additionally, pre-administration of TPPPS obviously reduced the size and delayed the occurrence of tumors induced by acute oncogenic ALV-J infection. This study revealed the prominent effects and feasible mechanisms of TPPPS in inhibiting ALV-J infection, thereby providing a novel prospect to control ALV-J spread.

  17. gga-miR-375 plays a key role in tumorigenesis post subgroup J avian leukosis virus infection.

    Science.gov (United States)

    Li, Hongxin; Shang, Huiqing; Shu, Dingming; Zhang, Huanmin; Ji, Jun; Sun, Baoli; Li, Hongmei; Xie, Qingmei

    2014-01-01

    Avian leukosis is a neoplastic disease caused in part by subgroup J avian leukosis virus J (ALV-J). Micro ribonucleic acids (miRNAs) play pivotal oncogenic and tumour-suppressor roles in tumour development and progression. However, little is known about the potential role of miRNAs in avian leukosis tumours. We have found a novel tumour-suppressor miRNA, gga-miR-375, associated with avian leukosis tumorigenesis by miRNA microarray in a previous report. We have also previously studied the biological function of gga-miR-375; Overexpression of gga-miR-375 significantly inhibited DF-1 cell proliferation, and significantly reduced the expression of yes-associated protein 1 (YAP1) by repressing the activity of a luciferase reporter carrying the 3'-untranslated region of YAP1. This indicates that gga-miR-375 is frequently downregulated in avian leukosis by inhibiting cell proliferation through YAP1 oncogene targeting. Overexpression of gga-miR-375 markedly promoted serum starvation induced apoptosis, and there may be the reason why the tumour cycle is so long in the infected chickens. In vivo assays, gga-miR-375 was significantly downregulated in chicken livers 20 days after infection with ALV-J, and YAP1 was significantly upregulated 20 days after ALV-J infection (Pleukosis tumorigenesis.

  18. Early regulation of viral infection reduces inflammation and rescues mx-positive mice from lethal avian influenza infection.

    Science.gov (United States)

    Song, Min-Suk; Cho, Young-Hun; Park, Su-Jin; Pascua, Philippe Noriel Q; Baek, Yun Hee; Kwon, Hyeok-Il; Lee, Ok-Jun; Kong, Byung-Whi; Kim, Hyunggee; Shin, Eui-Cheol; Kim, Chul-Joong; Choi, Young Ki

    2013-04-01

    Differing sensitivity of influenza A viruses to antiviral effects of the Myxovirus resistance (Mx) protein implies varying global gene expression profiles in the host. The role of Mx protein during lethal avian influenza (AI) virus infection was examined using Mx1-deficient C57BL/6 (B6-Mx1(-/-)) and congenic Mx1-expressing (B6-Mx1(+/+)) mice infected with a virulent, mouse-adapted avian H5N2 Ab/Korea/ma81/07 (Av/ma81) virus. After infection, B6-Mx1(+/+) mice were completely protected from lethal AI-induced mortality, and exhibited attenuated clinical disease and reduced viral titers and pathology in the lungs, compared with B6-Mx1(-/-) mice. Transcriptional profiling of lung tissues revealed that most of the genes up-regulated after infection are involved in activation of the immune response and host defense. Notably, more abundant and sustained expression of cytokine/chemokine genes was observed up to 3 dpi in B6-Mx1(-/-) mice, and this was associated with excessive induction of cytokines and chemokines. Consequently, massive infiltration of macrophages/monocytes and granulocytes into lung resulted in severe viral pneumonia and potentially contributed to decreased survival of B6-Mx1(-/-) mice. Taken together, our data show that dysregulated gene transcriptional activity corresponded to persistent induction of cytokine/chemokines and recruitment of cytokine-producing cells that promote inflammation in B6-Mx1(-/-) mouse lungs. Thus, we provide additional evidence of the interplay of genetic, molecular, and cellular correlates governed by the Mx1 protein that critically determine disease outcome during lethal AI virus infection.

  19. Radiological description about the globally first case of human infected avian influenza virus (H10N8 induced pneumonia

    Directory of Open Access Journals (Sweden)

    Jian He

    2016-03-01

    Full Text Available Human infected avian influenza (H10N8 is an acute infectious respiratory tract infection caused by JX346-H10N8. The reported case in this paper is the globally first case report about radiological description of human infected avian influenza (H10N8 virus related pneumonia. The patient showed an epidemiological history of contacts to living poultries and the incubation period lasted for 4 days. The condition was clinically characterized by fever, cough, chest distress and obvious hypoxia. CT scan demonstrated the lungs with large flake of hyper-intense consolidation, confined patch of ground glass opacity, dilated bronchi, predominantly dorsal thickening of the interlobular septum, and other types of lesions related to interstitial pulmonary edema. Meanwhile, accompanying interlobar effusion, infrapulmonary effusion and pleural effusion were demonstrated in a small quantity by CT scan. Human infected avian influenza (H10N8 related pneumonia should be differentiated from pneumonia induced by human infected avian influenza viruses H5N1 and H7N9. No characteristic key points for radiological differentiation have been found. And its definitive diagnosis should be based on the etiological examination.

  20. The clinical, pathological and microbiological outcome of an Escherichia coli O2:K1 infection in avian pneumovirus infected turkeys.

    Science.gov (United States)

    Van de Zande, S; Nauwynck, H; Pensaert, M

    2001-08-20

    The purpose of this study was to evaluate the effect of an Escherichia coli infection in avian pneumovirus (APV)-infected turkeys. One group of 2-week-old specific pathogen-free (SPF) and two groups of 3-week-old conventional (CON) turkeys were inoculated oculonasally with virulent APV subtype A alone, with E. coli O2:K1 alone or with both agents at varying intervals (1, 3, 5 or 7 days) between the two inoculations. The birds were followed clinically and examined for macroscopic lesions at necropsy. Titres of APV were determined in the turbinates, trachea, lungs and air sacs. The number of E. coli O2:K1were assessed in the turbinates, trachea, lungs, air sacs, liver and heart. In both SPF and CON turkeys, dual infection resulted in an increased morbidity and a higher incidence of gross lesions compared to the groups given single infections, especially with a time interval between APV and E. coli inoculations of 3 and 5 days. APV was isolated from the respiratory tract of all APV-infected groups between 3 and 7 days post inoculation. E. coli O2:K1 was isolated only from turkeys that received a dual infection. It was recovered from the turbinates, trachea, lungs, heart and liver. These results show that APV may act as a primary agent predisposing to E. coli colonization and invasion.

  1. Experimental infection of mice with avian paramyxovirus serotypes 1 to 9.

    Directory of Open Access Journals (Sweden)

    Sunil K Khattar

    Full Text Available The nine serotypes of avian paramyxoviruses (APMVs are frequently isolated from domestic and wild birds worldwide. APMV-1, also called Newcastle disease virus, was shown to be attenuated in non-avian species and is being developed as a potential vector for human vaccines. In the present study, we extended this evaluation to the other eight serotypes by evaluating infection in BALB/c mice. Mice were inoculated intranasally with a prototype strain of each of the nine serotypes and monitored for clinical disease, gross pathology, histopathology, virus replication and viral antigen distribution, and seroconversion. On the basis of multiple criteria, each of the APMV serotypes except serotype 5 was found to replicate in mice. Five of the serotypes produced clinical disease and significant weight loss in the following order of severity: 1, 2>6, 9>7. However, disease was short-lived. The other serotypes produced no evident clinical disease. Replication of all of the APMVs except APMV-5 in the nasal turbinates and lungs was confirmed by the recovery of infectious virus and by substantial expression of viral antigen in the epithelial lining detected by immunohistochemistry. Trace levels of infectious APMV-4 and -9 were detected in the brain of some animals; otherwise, no virus was detected in the brain, small intestine, kidney, or spleen. Histologically, infection with the APMVs resulted in lung lesions consistent with broncho-interstitial pneumonia of varying severity that were completely resolved at 14 days post infection. All of the mice infected with the APMVs except APMV-5 produced serotype-specific HI serum antibodies, confirming a lack of replication of APMV-5. Taken together, these results demonstrate that all APMV serotypes except APMV-5 are capable of replicating in mice with minimal disease and pathology.

  2. [Human factors caused the third plague epidemic in Harbin].

    Science.gov (United States)

    Jin, Dong-Ying; Li, Zhi-Ping

    2011-03-01

    The third plague epidemic in Harbin broke out in 1946 and ended in 1954. Different from the first two plague epidemics (imported), the third prevalence was both imported and idiopathic infectious disease which was caused by human factors. Japanese troops set forbidden zones to build a biological weapon center, which destroyed the natural environment and offered a good growth condition for Citellus Undulatus. In 1945, on the eve of surrender, the Japanese blew up the Unit 731 germ factory located in a bungalow district, which caused diffusion of infected plague fleas. Mice of the district were infected and a man-made plague focus was created. During the prevalence of the third plague, prevention departments at all levels took a series of actions and with people's efforts, the plague was effectively controlled.

  3. Viper Plague Project

    Science.gov (United States)

    2009-07-01

    a private herpetological collection infested with ticks (Kiel et al, 2006). Viper Plague presented signs and symptoms in the reptiles that were...1. Introduction The term Viper Plague was coined for a lethal disease state seen in snakes belonging to a private herpetological collection...Rattlesnake (Crotalus atrox). This was performed because this particular species of rattlesnake was present in the original herpetological collection

  4. Enzootic plague foci, Algeria

    Science.gov (United States)

    Malek, M.A.; Hammani, A.; Beneldjouzi, A.; Bitam, I.

    2014-01-01

    In Algeria, PCR sequencing of pla, glpD and rpoB genes found Yersinia pestis in 18/237 (8%) rodents of five species, including Apodemus sylvaticus, previously undescribed as pestiferous; and disclosed three new plague foci. Multiple spacer typing confirmed a new Orientalis variant. Rodent survey should be reinforced in this country hosting reemerging plague. PMID:25834736

  5. Enzootic plague foci, Algeria

    Directory of Open Access Journals (Sweden)

    M.A. Malek

    2015-03-01

    Full Text Available In Algeria, PCR sequencing of pla, glpD and rpoB genes found Yersinia pestis in 18/237 (8% rodents of five species, including Apodemus sylvaticus, previously undescribed as pestiferous; and disclosed three new plague foci. Multiple spacer typing confirmed a new Orientalis variant. Rodent survey should be reinforced in this country hosting reemerging plague.

  6. gga-miR-375 plays a key role in tumorigenesis post subgroup J avian leukosis virus infection.

    Directory of Open Access Journals (Sweden)

    Hongxin Li

    Full Text Available Avian leukosis is a neoplastic disease caused in part by subgroup J avian leukosis virus J (ALV-J. Micro ribonucleic acids (miRNAs play pivotal oncogenic and tumour-suppressor roles in tumour development and progression. However, little is known about the potential role of miRNAs in avian leukosis tumours. We have found a novel tumour-suppressor miRNA, gga-miR-375, associated with avian leukosis tumorigenesis by miRNA microarray in a previous report. We have also previously studied the biological function of gga-miR-375; Overexpression of gga-miR-375 significantly inhibited DF-1 cell proliferation, and significantly reduced the expression of yes-associated protein 1 (YAP1 by repressing the activity of a luciferase reporter carrying the 3'-untranslated region of YAP1. This indicates that gga-miR-375 is frequently downregulated in avian leukosis by inhibiting cell proliferation through YAP1 oncogene targeting. Overexpression of gga-miR-375 markedly promoted serum starvation induced apoptosis, and there may be the reason why the tumour cycle is so long in the infected chickens. In vivo assays, gga-miR-375 was significantly downregulated in chicken livers 20 days after infection with ALV-J, and YAP1 was significantly upregulated 20 days after ALV-J infection (P<0.05. We also found that expression of cyclin E, an important regulator of cell cycle progression, was significantly upregulated (P<0.05. Drosophila inhibitor of apoptosis protein 1 (DIAP1, which is related to caspase-dependent apoptosis, was also significantly upregulated after infection. Our data suggests that gga-miR-375 may function as a tumour suppressor thereby regulating cancer cell proliferation and it plays a key role in avian leukosis tumorigenesis.

  7. Avian Flu

    Energy Technology Data Exchange (ETDEWEB)

    Eckburg, Paul

    2006-11-06

    Since 2003, a severe form of H5N1 avian influenza has rapidly spread throughout Asia and Europe, infecting over 200 humans in 10 countries. The spread of H5N1 virus from person-to-person has been rare, thus preventing the emergence of a widespread pandemic. However, this ongoing epidemic continues to pose an important public health threat. Avian flu and its pandemic potential in humans will be discussed.

  8. Spleen transcriptome response to infection with avian pathogenic Escherichia coli in broiler chickens

    Directory of Open Access Journals (Sweden)

    Kariyawasam Subhashinie

    2011-09-01

    Full Text Available Abstract Background Avian pathogenic Escherichia coli (APEC is detrimental to poultry health and its zoonotic potential is a food safety concern. Regulation of antimicrobials in food-production animals has put greater focus on enhancing host resistance to bacterial infections through genetics. To better define effective mechanism of host resistance, global gene expression in the spleen of chickens, harvested at two times post-infection (PI with APEC, was measured using microarray technology, in a design that will enable investigation of effects of vaccination, challenge, and pathology level. Results There were 1,101 genes significantly differentially expressed between severely infected and non-infected groups on day 1 PI and 1,723 on day 5 PI. Very little difference was seen between mildly infected and non-infected groups on either time point. Between birds exhibiting mild and severe pathology, there were 2 significantly differentially expressed genes on day 1 PI and 799 on day 5 PI. Groups with greater pathology had more genes with increased expression than decreased expression levels. Several predominate immune pathways, Toll-like receptor, Jak-STAT, and cytokine signaling, were represented between challenged and non-challenged groups. Vaccination had, surprisingly, no detectible effect on gene expression, although it significantly protected the birds from observable gross lesions. Functional characterization of significantly expressed genes revealed unique gene ontology classifications during each time point, with many unique to a particular treatment or class contrast. Conclusions More severe pathology caused by APEC infection was associated with a high level of gene expression differences and increase in gene expression levels. Many of the significantly differentially expressed genes were unique to a particular treatment, pathology level or time point. The present study not only investigates the transcriptomic regulations of APEC infection

  9. Experimental infection of turkeys with avian pneumovirus and either Newcastle disease virus or Escherichia coli.

    Science.gov (United States)

    Turpin, Elizabeth A; Perkins, Laura E L; Swayne, David E

    2002-01-01

    Avian pneumoviruses (APVs) are RNA viruses responsible for upper respiratory disease in poultry. Experimental infections are typically less severe than those observed in field cases. Previous studies with APV and Escherichia coli suggest this discrepancy is due to secondary agents. Field observations indicate APV infections are more severe with concurrent infection by Newcastle disease virus (NDV). In the current study, we examined the role of lentogenic NDV in the APV disease process. Two-week-old commercial turkey poults were infected with the Colorado strain of APV. Three days later, these poults received an additional inoculation of either NDV or E. coli. Dual infection of APV with either NDV or E. coli resulted in increased morbidity rates, with poults receiving APV/NDV having the highest morbidity rates and displaying lesions of swollen infraorbital sinuses. These lesions were not present in the single APV, NDV, or E coli groups. These results demonstrate that coinfection with APV and NDV can result in clinical signs and lesions similar to those in field outbreaks of APV.

  10. Use of molecularly cloned avian leukosis virus to study antigenic variation following infection of meat-type chickens

    Science.gov (United States)

    A molecularly cloned strain of subgroup J avian leukosis virus (ALV-J) termed R5-4 was used to study antigenic variation following infection of meat-type chickens. Chickens were inoculated with R5-4 virus at either 8 days of embryonation or at 1 week of age. Each chicken was housed in a separate is...

  11. Characterization of cytokine expression induced by avian influenza virus infection with real-time RT-PCR

    Science.gov (United States)

    Knowledge of how birds react to infection from avian influenza virus is critical to understanding disease pathogenesis and host response. The use of real-time (R), reverse-transcriptase (RT), PCR to measure innate immunity, including cytokine and interferon gene expression, has become a standard tec...

  12. Strategies for differentiating infection in vaccinated animals (DIVA) for foot-and-mouth disease, classical swine fever and avian influenza

    DEFF Research Database (Denmark)

    Uttenthal, Åse; Parida, Satya; Rasmussen, Thomas Bruun;

    2010-01-01

    for the presence of infection. This literature review describes the current knowledge on the use of DIVA diagnostic strategies for three important transboundary animal diseases: foot-and-mouth disease in cloven-hoofed animals, classical swine fever in pigs and avian influenza in poultry....

  13. Avian paramyxovirus serotype 3 infection in Neopsephotus, Cyanoramphus, and Neophema species.

    Science.gov (United States)

    Jung, Arne; Grund, Christian; Müller, Inge; Rautenschlein, Silke

    2009-09-01

    An outbreak of avian paramyxovirus serotype 3 (APMV-3) infection occurred in a private bird collection consisting mainly of Neophema species. Two Bourke's parrots (Neopsephotus bourkii) and one red-crowned parakeet (Cyanoramphus novaezelandiae) were examined after developing torticollis and circling. The 3 birds were euthanatized and submitted for necropsy. Brain and liver samples from the 3 birds were homogenized and inoculated into the allantoic cavity of 10-day-old embryonated specific-pathogen-free chicken eggs. An APMV-3 isolate replicated but did not induce embryonic mortality after up to 5 consecutive passages. Allantoic fluid from the second passage was used in hemagglutination testing performed on chicken erythrocytes, which resulted in a titer of 64 hemagglutinating units. Avian paramyxovirus serotype 3 was identified in the allantoic fluid, and a reverse transcription polymerase chain reaction verified the isolate as APMV-3/parakeet. An eventual mortality rate of 70% occurred in the Neophema species, but a group of budgerigars (Melopsittacus undulatus) and parrotlets (Forpus species) kept in the same facility showed no clinical signs during the outbreak.

  14. Identification of duck plague virus by polymerase chain reaction

    Science.gov (United States)

    Hansen, W.R.; Brown, Sean E.; Nashold, S.W.; Knudson, D.L.

    1999-01-01

    A polymerase chain reaction (PCR) assay was developed for detecting duck plague virus. A 765-bp EcoRI fragment cloned from the genome of the duck plague vaccine (DP-VAC) virus was sequenced for PCR primer development. The fragment sequence was found by GenBank alignment searches to be similar to the 3a?? ends of an undefined open reading frame and the gene for DNA polymerase protein in other herpesviruses. Three of four primer sets were found to be specific for the DP-VAC virus and 100% (7/7) of field isolates but did not amplify DNA from inclusion body disease of cranes virus. The specificity of one primer set was tested with genome templates from other avian herpesviruses, including those from a golden eagle, bald eagle, great horned owl, snowy owl, peregrine falcon, prairie falcon, pigeon, psittacine, and chicken (infectious laryngotracheitis), but amplicons were not produced. Hence, this PCR test is highly specific for duck plague virus DNA. Two primer sets were able to detect 1 fg of DNA from the duck plague vaccine strain, equivalent to five genome copies. In addition, the ratio of tissue culture infectious doses to genome copies of duck plague vaccine virus from infected duck embryo cells was determined to be 1:100, making the PCR assay 20 times more sensitive than tissue culture for detecting duck plague virus. The speed, sensitivity, and specificity of this PCR provide a greatly improved diagnostic and research tool for studying the epizootiology of duck plague. /// Se desarroll?? una prueba de reacci??n en cadena por la polimerasa para detectar el virus de la peste del pato. Un fragmento EcoRI de 765 pares de bases clonado del genoma del virus vacunal de la peste del pato fue secuenciado para la obtenci??n de los iniciadores de la prueba de la reacci??n en cadena por la polimerasa. En investigaciones de alineaci??n en el banco de genes ('GenBank') se encontr?? que la secuencia del fragmento era similar a los extremos 3a?? de un marco de lectura abierto

  15. Histopatologia da infecção por Yersinia pestis em roedores de focos de peste do Nordeste brasileiro Histopathology of Yersinia pestis infection in rodents from plague foci of Brazilian Northeast

    Directory of Open Access Journals (Sweden)

    Eridan M. Coutinho

    1982-06-01

    Full Text Available O presente trabalho mostra a histopatologia da infecção pela Yersinia pestis, entre as diferentes espécies de roedores silvestres e comensais (cricetídeos, equimídeos, murídeos e cavídeos que ocorrem na zona endêmica de peste do Nordeste do Brasil. Estes roedores foram encontrados naturalmente infectados nos campos ou inoculados experimentalmente no laboratório (vias percutânea, subcutânea ou picada de pulgas com cepas locais e/ou estrangeiras de Yersiniapestis. Quase todos os animais, exceto alguns dos cavídeos, desenvolveram a forma bubosepticêmica da peste. Entre as lesões encontradas, a necrose coagulativa multifocal do fígado, a pneumonite intersticial aguda difusa e a atrofia linfoide do baço, podem, por sua constância, ser consideradas como os principais indicadores histológicos da infecção pestosa, embora estas lesões não sejam exclusivas da peste. A diversidade e a intensidade das lesões entre os Zygodontomys lasiurus pixuna, podem explicar a mortalidade elevada desta espécie e a disseminação da peste nos focos naturais do Nordeste brasileiro. Cricetídeos e murídeos mostraram alterações histopatológicas qualitativamente semelhantes. A resistência dos cavídeos à infecção pestosa foi evidenciada pela sobrevida desses roedores à fase aguda da infecção e pelo desenvolvimento de uma reação histiocitária interna, delimitando as áreas abscedadas. è possível que estas lesões crônicas abriguem bacilos virulentos, que permitirão a reinfecção periódica das pulgas e conseqüente reativação do processo epizoótico.In this paper, the histopathological aspects of plague infection in different species of wild and domestic rodents (cricetidae, echymidae, muridae and cavidae are described. All of them had been trapped in endemic plague areas and harboured natural infection, while others were laboratory infected by different routes (percutaneous, subcutaneous rout, fleas bite. Several national and

  16. Avian pox virus infection in a common barn owl (Tyto alba in southern Brazil

    Directory of Open Access Journals (Sweden)

    Gilberto D. Vargas

    2011-07-01

    Full Text Available A young common barn owl (Tyto alba was referred to the Núcleo de Reabilitação da Fauna Silvestre (Nurfs, Federal University of Pelotas (UFPel, after been found in a barn of a brick factory in the urban area of Pelotas, Rio Grande do Sul, Brazil. The bird was apathic, weak and with crusty lesions in the featherless areas (eyes, beak, legs, and died soon after arrival at Nurfs. Necropsy and histopathological examination of the lesions were carried out. The hyperplasia and hypertrophy of the cutaneous lesions, several eosinophilic intracyto-plasmic inclusion bodies in epithelial cells (Bollinger bodies, as well as particles characteristic of poxvirus, observed by electronic microscopy, confirmed the infection by avian poxvirus, what highlights the importance of Tyto alba as carrier of the virus in the wild.

  17. Macaque proteome response to highly pathogenic avian influenza and 1918 reassortant influenza virus infections.

    Science.gov (United States)

    Brown, Joseph N; Palermo, Robert E; Baskin, Carole R; Gritsenko, Marina; Sabourin, Patrick J; Long, James P; Sabourin, Carol L; Bielefeldt-Ohmann, Helle; García-Sastre, Adolfo; Albrecht, Randy; Tumpey, Terrence M; Jacobs, Jon M; Smith, Richard D; Katze, Michael G

    2010-11-01

    The host proteome response and molecular mechanisms that drive disease in vivo during infection by a human isolate of the highly pathogenic avian influenza virus (HPAI) and 1918 pandemic influenza virus remain poorly understood. This study presents a comprehensive characterization of the proteome response in cynomolgus macaque (Macaca fascicularis) lung tissue over 7 days of infection with HPAI (the most virulent), a reassortant virus containing 1918 hemagglutinin and neuraminidase surface proteins (intermediate virulence), or a human seasonal strain (least virulent). A high-sensitivity two-dimensional liquid chromatography-tandem mass spectroscopy strategy and functional network analysis were implemented to gain insight into response pathways activated in macaques during influenza virus infection. A macaque protein database was assembled and used in the identification of 35,239 unique peptide sequences corresponding to approximately 4,259 proteins. Quantitative analysis identified an increase in expression of 400 proteins during viral infection. The abundance levels of a subset of these 400 proteins produced strong correlations with disease progression observed in the macaques, distinguishing a "core" response to viral infection from a "high" response specific to severe disease. Proteome expression profiles revealed distinct temporal response kinetics between viral strains, with HPAI inducing the most rapid response. While proteins involved in the immune response, metabolism, and transport were increased rapidly in the lung by HPAI, the other viruses produced a delayed response, characterized by an increase in proteins involved in oxidative phosphorylation, RNA processing, and translation. Proteomic results were integrated with previous genomic and pathological analysis to characterize the dynamic nature of the influenza virus infection process.

  18. Effect of Infection with a Mesogenic Strain of Newcastle Disease Virus on Infection with Highly Pathogenic Avian Influenza Virus in Chickens

    Science.gov (United States)

    Little is known on the interactions between avian influenza virus (AIV) and Newcastle disease virus (NDV) when coinfecting the same poultry host. In a previous study we found that infection of chickens with a mesogenic strain of NDV (mNDV) can reduce highly pathogenic AIV (HPAIV) replication, clinic...

  19. Prior infection of pigs with swine influenza viruses is a barrier to infection with avian influenza viruses.

    Science.gov (United States)

    De Vleeschauwer, Annebel; Van Reeth, Kristien

    2010-12-15

    Although pigs are susceptible to avian influenza viruses (AIV) of different subtypes, the incidence of AIV infections in the field appears to be low. Swine H1N1, H3N2 and H1N2 influenza viruses (SIV) are enzootic worldwide and most pigs have antibodies to 1 or more SIV subtypes. This study aimed to examine whether infection-immunity to H1N1 or H3N2 SIV may (1) protect pigs against subsequent infections with AIV of various haemagglutinin and/or neuraminidase subtypes and/or (2) interfere with the serological diagnosis of AIV infection by haemagglutination inhibition (HI) or virus neutralization (VN) tests. Pigs were inoculated intranasally with an H1N1 or H3N2 SIV or left uninoculated. Four or 6 weeks later all pigs were challenged intranasally with 1 of 3 AIV subtypes (H4N6, H5N2 or H7N1). Fifteen out of 17 challenge control pigs shed the respective AIV for 4-6 days post-inoculation and 16 developed HI and VN antibodies. In contrast, 28 of the 29 SIV-immune pigs did not have detectable AIV shedding. Only 12 SIV-immune pigs developed HI antibodies to the AIV used for challenge and 14 had VN antibodies. Antibody titres to the AIV were low in both control and SIV-immune pigs. Our data show that prior infection of pigs with SIV is a barrier to infection with AIV of unrelated subtypes. Serological screening in regions where SIV is enzootic is only useful when the AIV strain for which the pigs need to be tested is known.

  20. Non-Human Primates Harbor Diverse Mammalian and Avian Astroviruses Including Those Associated with Human Infections.

    Directory of Open Access Journals (Sweden)

    Erik A Karlsson

    Full Text Available Astroviruses (AstVs are positive sense, single-stranded RNA viruses transmitted to a wide range of hosts via the fecal-oral route. The number of AstV-infected animal hosts has rapidly expanded in recent years with many more likely to be discovered because of the advances in viral surveillance and next generation sequencing. Yet no study to date has identified human AstV genotypes in animals, although diverse AstV genotypes similar to animal-origin viruses have been found in children with diarrhea and in one instance of encephalitis. Here we provide important new evidence that non-human primates (NHP can harbor a wide variety of mammalian and avian AstV genotypes, including those only associated with human infection. Serological analyses confirmed that >25% of the NHP tested had antibodies to human AstVs. Further, we identified a recombinant AstV with parental relationships to known human AstVs. Phylogenetic analysis suggests AstVs in NHP are on average evolutionarily much closer to AstVs from other animals than are AstVs from bats, a frequently proposed reservoir. Our studies not only demonstrate that human astroviruses can be detected in NHP but also suggest that NHP are unique in their ability to support diverse AstV genotypes, further challenging the paradigm that astrovirus infection is species-specific.

  1. Avian malaria in Hawaiian forest birds: Infection and population impacts across species and elevations

    Science.gov (United States)

    Samuel, Michael D.; Woodworth, Bethany L.; Atkinson, Carter T.; Hart, P. J.; LaPointe, Dennis

    2015-01-01

    Wildlife diseases can present significant threats to ecological systems and biological diversity, as well as domestic animal and human health. However, determining the dynamics of wildlife diseases and understanding the impact on host populations is a significant challenge. In Hawai‘i, there is ample circumstantial evidence that introduced avian malaria (Plasmodium relictum) has played an important role in the decline and extinction of many native forest birds. However, few studies have attempted to estimate disease transmission and mortality, survival, and individual species impacts in this distinctive ecosystem. We combined multi-state capture-recapture (longitudinal) models with cumulative age-prevalence (cross-sectional) models to evaluate these patterns in Apapane, Hawai‘i Amakihi, and Iiwi in low-, mid-, and high-elevation forests on the island of Hawai‘i based on four longitudinal studies of 3–7 years in length. We found species-specific patterns of malaria prevalence, transmission, and mortality rates that varied among elevations, likely in response to ecological factors that drive mosquito abundance. Malaria infection was highest at low elevations, moderate at mid elevations, and limited in high-elevation forests. Infection rates were highest for Iiwi and Apapane, likely contributing to the absence of these species in low-elevation forests. Adult malaria fatality rates were highest for Iiwi, intermediate for Amakihi at mid and high elevations, and lower for Apapane; low-elevation Amakihi had the lowest malaria fatality, providing strong evidence of malaria tolerance in this low-elevation population. Our study indicates that hatch-year birds may have greater malaria infection and/or fatality rates than adults. Our study also found that mosquitoes prefer feeding on Amakihi rather than Apapane, but Apapane are likely a more important reservoir for malaria transmission to mosquitoes. Our approach, based on host abundance and infection rates, may be an

  2. NHE1 gene associated with avian leukosis virus subgroup J infection in chicken.

    Science.gov (United States)

    Chen, Biao; Pan, Weiling; Zhang, Liangyu; Liu, Jing; Ouyang, Hongjia; Nie, Qinghua; Zhang, Xiquan

    2014-10-01

    As a kind of binding protein, the type 1 Na(+)/H(+) exchanger (NHE1) is a receptor for the highly pathogenic Avian leukosis viruses-J subgroup (ALV-J) in chicken. In order to investigate the potential effect of chicken NHE1 gene on leukosis, we compared its expression between ALV-J-affected and -unaffected chicken, screened variations across the whole gene, and then performed association analysis with ALV-J affected/unaffected trait in three un-related chicken populations. We found that the NHE1 gene expressed in four immune tissues including spleen, bursa fabricius, liver, and thymus, and its expression was significantly up-regulated in liver and thymus of ALV-J-affected chickens (with leukosis phenotype) compared to -unaffected ones (ALV-J-negative controls). Thirty-six single nucleotide polymorphisms (SNP) were identified in a 6,105 bp region of the chicken NHE1 gene, giving rise to every 170 bp per SNP. Two SNP of g.4405A>G and g.5886C>G were genotyped with PCR-RFLP method. Results showed that g.4405A>G was significantly associated (P G was significantly associated (P < 0.05) with ALV-J infection in SY. These results indicated that the NHE1 gene was related to ALV-J infection in chicken.

  3. Hemato-biochemical and pathological changes on avian influenza in naturally infected domestic ducks in Egypt

    Directory of Open Access Journals (Sweden)

    Essam A. Mahmoud

    2015-10-01

    Full Text Available Aim: Few studies have been made in regard to avian influenza (AI in ducks, thus the aim of this work was planned to investigate the hematological, biochemical, and pathological changes in domestic Egyptian ducks naturally infected with AI. Materials and Methods: 30 duck from private backyards 3-month-old 15 were clinically healthy (Group 1 and the other fifteen (Group 2 were naturally diseased with AI (H5N1. The disease was diagnosed by polymerase chain reaction as H5N1. Results: Duck showed cyanosis, subcutaneous edema of head and neck with nervous signs (torticollis. Hematological studies revealed a microcytic hypochromic anemia. Biochemical studies revealed a significant decrease in total protein, albumin and globulin concentration with significant increase of activities of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, Υ-glutamyl transpeptidase, lactic acid dehydrogenase and creatine phsphokinase. Prominent increase in creatinine and uric acid in addition to hypocalcemia and hyperphosphatemia were significantly detected in the infected ducks. Histopathological finding confirm these investigations. Conclusion: The highly pathogenic AIV (A/H5N1 became more severe infectious to ducks than before and causes nervous manifestations and blindness which were uncommon in ducks. Besides the significant increases of hepatic enzymes, brain, heart, and renal markers as a response to virus damage to these organs.

  4. Fatal hemoprotozoal infections in multiple avian species in a zoological park.

    Science.gov (United States)

    Ferrell, Shannon T; Snowden, Karen; Marlar, Annajane B; Garner, Michael; Lung, Nancy P

    2007-06-01

    Over a 3-yr span, two juvenile lesser flamingos (Phoeniconaias minor), two green jays (Cyanocorax yncas glaucescens), and two Montezuma oropendolas (Psarocolius montezuma) died peracutely with no premonitory signs at a zoological park in the southern United States. At necropsy, the birds were in excellent body condition. Except for one green jay, the coelomic cavities were filled with a dark serosanguineous fluid. Splenomegaly and hepatomegaly were present. The livers were tan to purple with numerous, randomly distributed red-to-black foci, ranging in size from 1 to 4 mm. The predominant histopathologic finding, except in one green jay, was large protozoal cysts in the hepatic parenchyma. Histologically, the protozoal cysts were restricted to the liver, and none were identified in the skeletal muscle, spleen, or other tissues. Frozen tissue samples harvested at necropsy had a nested polymerase chain reaction assay performed to amplify the mitochondrial cytochrome B gene of the protozoa. The amplified gene sequences were compared with reference cytochrome B gene sequences for avian Plasmodium spp., Haemoproteus spp., and Leucocytozoon spp. The protozoal parasite within the hepatic parenchyma from the Montezuma oropendolas and the lesser flamingos was identified as Haemoproteus spp. Both green jays had Plasmodium spp. isolated from the submitted tissue samples. The peracute nature of the infections precluded any successful medical intervention, making prevention by exclusion the principal means to control hemoprotozoal transmission. There are no reports in the literature documenting identified fatal hemoprotozoal infections in oropendolas, green jays, or lesser flamingos.

  5. A recombinant avian leukosis virus subgroup j for directly monitoring viral infection and the selection of neutralizing antibodies.

    Directory of Open Access Journals (Sweden)

    Qi Wang

    Full Text Available Avian leukosis virus subgroup J (ALV-J has induced serious clinical outbreaks and has become a serious infectious disease of chickens in China. We describe here the creation of a recombinant ALV-J tagged with the enhanced green fluorescent protein (named rHPRS-103EGFP. We successfully utilize the rHPRS-103EGFP to visualize viral infection and for development of a simplified serum-neutralization test.

  6. A recombinant avian leukosis virus subgroup j for directly monitoring viral infection and the selection of neutralizing antibodies.

    Science.gov (United States)

    Wang, Qi; Li, Xiaofei; Ji, Xiaolin; Wang, Jingfei; Shen, Nan; Gao, Yulong; Qi, Xiaole; Wang, Yongqiang; Gao, Honglei; Zhang, Shide; Wang, Xiaomei

    2014-01-01

    Avian leukosis virus subgroup J (ALV-J) has induced serious clinical outbreaks and has become a serious infectious disease of chickens in China. We describe here the creation of a recombinant ALV-J tagged with the enhanced green fluorescent protein (named rHPRS-103EGFP). We successfully utilize the rHPRS-103EGFP to visualize viral infection and for development of a simplified serum-neutralization test.

  7. Avian Influenza A(H7N9) Virus Infection in 2 Travelers Returning from China to Canada, January 20151

    Science.gov (United States)

    Chambers, Catharine; Gustafson, Reka; Purych, Dale B.; Tang, Patrick; Bastien, Nathalie; Krajden, Mel; Li, Yan

    2016-01-01

    In January 2015, British Columbia, Canada, reported avian influenza A(H7N9) virus infection in 2 travelers returning from China who sought outpatient care for typical influenza-like illness. There was no further spread, but serosurvey findings showed broad population susceptibility to H7N9 virus. Travel history and timely notification are critical to emerging pathogen detection and response. PMID:26689320

  8. Infection of children with avian-human reassortant influenza virus from pigs in Europe

    NARCIS (Netherlands)

    E.C.J. Claas (Eric); Y. Kawaoka (Yoshihiro); J.C. de Jong (Jan); N. Masurel (Nic); R.G. Webster (Robert)

    1994-01-01

    textabstractPigs have been proposed to act as the intermediate hosts in the generation of pandemic human influenza strains by reassortment of genes from avian and human influenza virus strains. The circulation of avian-like H1N1 influenza viruses in European pigs since 1979 and the detection of huma

  9. A returning migrant worker with avian influenza A (H7N9) virus infection in Guizhou, China: a case report

    OpenAIRE

    Wang, Dingming; Tang, Guangpeng; Huang, Yan; Yu, Chun; Li, Shijun; Zhuang, Li; Fu, Lin; Wang, Shiping; Li, Nanshi; Li, Xiyan; Yang, Lei; Lan, Yu; Bai, Tian; Shu, Yuelong

    2015-01-01

    Introduction Human infection with avian influenza A (H7N9) virus was first reported on March, 2013 in the Yangtze River Delta region of China. The majority of human cases were detected in mainland China; other regions out of mainland China reported imported human cases, including Hong Kong SAR, Taiwan (the Republic of China) and Malaysia, due to human transportation. Here, we report the first human case of H7N9 infection imported into Guizhou Province during the Spring Festival travel season ...

  10. Plague in Yosemite

    Centers for Disease Control (CDC) Podcasts

    2017-03-23

    Dr. Vicki Kramer, with the California Department of Public Health, discusses two cases of plague in Yosemite National Park.  Created: 3/23/2017 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 3/23/2017.

  11. The first lack of evidence of H7N9 avian influenza virus infections among pigs in Eastern China.

    Science.gov (United States)

    Zhao, Fu-Rong; Zhou, Dong-Hui; Lin, Tong; Shao, Jun-Jun; Wei, Ping; Zhang, Yong-Guang; Chang, Hui-Yun

    2015-03-01

    In this study, we sought to examine whether evidence existed suggesting that pigs were being infected with the novel H7N9 avian influenza virus. From November 2012 to November 2013, blood was drawn from 1560 pigs from 100 large farms in 4 provinces of eastern China. Many of these pigs were in close proximity to wild birds or poultry. Swine sera were studied using hemagglutinin inhibition (HI) assays and enzyme-linked immunosorbent assays (ELISAs) against the H7 antigen derived from the emergent H7N9 avian influenza virus (AIV). Only 29 of the 1560 samples had HI titers of 1:20 when using the H7N9 AIV antigens, and none of the 29 (H7N9 AIV) HI-positive samples were positive when using ELISA, indicating that no samples were positive for H7N9. The negative results were also verified using a novel competitive HA-ELISA. As pigs have been shown to be infected with other avian influenza viruses and as the prevalence of novel influenza A viruses (e.g., H7N9 AIV) may be increasing among poultry in China, similar seroepidemiological studies of pigs should be periodically conducted in the future.

  12. Neuropathogenesis of a highly pathogenic avian influenza virus (H7N1 in experimentally infected chickens

    Directory of Open Access Journals (Sweden)

    Chaves Aida J

    2011-10-01

    Full Text Available Abstract In order to understand the mechanism of neuroinvasion of a highly pathogenic avian influenza virus (HPAIV into the central nervous system (CNS of chickens, specific pathogen free chickens were inoculated with a H7N1 HPAIV. Blood, cerebrospinal fluid (CSF, nasal cavity and brain tissue samples were obtained from 1 to 4 days post-inoculation (dpi of infected and control chickens. Viral antigen topographical distribution, presence of influenza A virus receptors in the brain, as well as, the role of the olfactory route in virus CNS invasion were studied using different immunohistochemistry techniques. Besides, viral RNA load in CSF and blood was quantified by means of a quantitative real-time reverse transcription-polymerase chain reaction. Viral antigen was observed widely distributed in the CNS, showing bilateral and symmetrical distribution in the nuclei of the diencephalon, mesencephalon and rhombencephalon. Viral RNA was detected in blood and CSF at one dpi, indicating that the virus crosses the blood-CSF-barrier early during infection. This early dissemination is possibly favoured by the presence of Siaα2,3 Gal and Siaα2,6 Gal receptors in brain vascular endothelial cells, and Siaα2,3 Gal receptors in ependymal and choroid plexus cells. No viral antigen was observed in olfactory sensory neurons, while the olfactory bulb showed only weak staining, suggesting that the virus did not use this pathway to enter into the brain. The sequence of virus appearance and the topographical distribution of this H7N1 HPAIV indicate that the viral entry occurs via the haematogenous route, with early and generalized spreading through the CSF.

  13. Proteomic analysis of chicken embryonic trachea and kidney tissues after infection in ovo by avian infectious bronchitis coronavirus

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    Kong Xiangang

    2011-03-01

    Full Text Available Abstract Background Avian infectious bronchitis (IB is one of the most serious diseases of economic importance in chickens; it is caused by the avian infectious coronavirus (IBV. Information remains limited about the comparative protein expression profiles of chicken embryonic tissues in response to IBV infection in ovo. In this study, we analyzed the changes of protein expression in trachea and kidney tissues from chicken embryos, following IBV infection in ovo, using two-dimensional gel electrophoresis (2-DE coupled with matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry (MALDI-TOF-TOF MS. Results 17 differentially expressed proteins from tracheal tissues and 19 differentially expressed proteins from kidney tissues were identified. These proteins mostly related to the cytoskeleton, binding of calcium ions, the stress response, anti-oxidative, and macromolecular metabolism. Some of these altered proteins were confirmed further at the mRNA level using real-time RT-PCR. Moreover, western blotting analysis further confirmed the changes of annexin A5 and HSPB1 during IBV infection. Conclusions To the best of our knowledge, we have performed the first analysis of the proteomic changes in chicken embryonic trachea and kidney tissues during IBV infection in ovo. The data obtained should facilitate a better understanding of the pathogenesis of IBV infection.

  14. Predicting Avian Influenza Co-Infection with H5N1 and H9N2 in Northern Egypt

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    Sean G. Young

    2016-09-01

    Full Text Available Human outbreaks with avian influenza have been, so far, constrained by poor viral adaptation to non-avian hosts. This could be overcome via co-infection, whereby two strains share genetic material, allowing new hybrid strains to emerge. Identifying areas where co-infection is most likely can help target spaces for increased surveillance. Ecological niche modeling using remotely-sensed data can be used for this purpose. H5N1 and H9N2 influenza subtypes are endemic in Egyptian poultry. From 2006 to 2015, over 20,000 poultry and wild birds were tested at farms and live bird markets. Using ecological niche modeling we identified environmental, behavioral, and population characteristics of H5N1 and H9N2 niches within Egypt. Niches differed markedly by subtype. The subtype niches were combined to model co-infection potential with known occurrences used for validation. The distance to live bird markets was a strong predictor of co-infection. Using only single-subtype influenza outbreaks and publicly available ecological data, we identified areas of co-infection potential with high accuracy (area under the receiver operating characteristic (ROC curve (AUC 0.991.

  15. Predicting Avian Influenza Co-Infection with H5N1 and H9N2 in Northern Egypt.

    Science.gov (United States)

    Young, Sean G; Carrel, Margaret; Malanson, George P; Ali, Mohamed A; Kayali, Ghazi

    2016-01-01

    Human outbreaks with avian influenza have been, so far, constrained by poor viral adaptation to non-avian hosts. This could be overcome via co-infection, whereby two strains share genetic material, allowing new hybrid strains to emerge. Identifying areas where co-infection is most likely can help target spaces for increased surveillance. Ecological niche modeling using remotely-sensed data can be used for this purpose. H5N1 and H9N2 influenza subtypes are endemic in Egyptian poultry. From 2006 to 2015, over 20,000 poultry and wild birds were tested at farms and live bird markets. Using ecological niche modeling we identified environmental, behavioral, and population characteristics of H5N1 and H9N2 niches within Egypt. Niches differed markedly by subtype. The subtype niches were combined to model co-infection potential with known occurrences used for validation. The distance to live bird markets was a strong predictor of co-infection. Using only single-subtype influenza outbreaks and publicly available ecological data, we identified areas of co-infection potential with high accuracy (area under the receiver operating characteristic (ROC) curve (AUC) 0.991).

  16. Development of a reverse transcription loop-mediated isothermal amplification assay for the rapid diagnosis of avian influenza A (H7N9) virus infection.

    Science.gov (United States)

    Nakauchi, Mina; Takayama, Ikuyo; Takahashi, Hitoshi; Tashiro, Masato; Kageyama, Tsutomu

    2014-08-01

    A genetic diagnosis system for detecting avian influenza A (H7N9) virus infection using reverse transcription-loop-mediated isothermal amplification (RT-LAMP) technology was developed. The RT-LAMP assay showed no cross-reactivity with seasonal influenza A (H3N2 and H1N1pdm09) or influenza B viruses circulating in humans or with avian influenza A (H5N1) viruses. The sensitivity of the RT-LAMP assay was 42.47 copies/reaction. Considering the high specificity and sensitivity of the assay for detecting the avian influenza A (H7N9) virus and that the reaction was completed within 30 min, the RT-LAMP assay developed in this study is a promising rapid diagnostic tool for avian influenza A (H7N9) virus infection.

  17. Human plague occurrences in Africa

    DEFF Research Database (Denmark)

    Neerinckx, Simon; Bertherat, Eric; Leirs, Herwig

    2010-01-01

    Plague remains a public health concern worldwide, but particularly in Africa. Despite the long-standing history of human plague, it is difficult to get a historical and recent overview of the general situation. We searched and screened available information sources on human plague occurrences...... Africa and Madagascar. We show that public health concerns regarding the current plague situation are justified and that the disease should not be neglected, despite the sometimes questionability of the numbers of cases. We conclude that improving plague surveillance strategies is absolutely necessary...

  18. Lovastatin protects against experimental plague in mice.

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    Saravanan Ayyadurai

    Full Text Available BACKGROUND: Plague is an ectoparasite-borne deadly infection caused by Yersinia pestis, a bacterium classified among the group A bioterrorism agents. Thousands of deaths are reported every year in some African countries. Tetracyclines and cotrimoxazole are used in the secondary prophylaxis of plague in the case of potential exposure to Y. pestis, but cotrimoxazole-resistant isolates have been reported. There is a need for additional prophylactic measures. We aimed to study the effectiveness of lovastatin, a cholesterol-lowering drug known to alleviate the symptoms of sepsis, for plague prophylaxis in an experimental model. METHODOLOGY: Lovastatin dissolved in Endolipide was intraperitoneally administered to mice (20 mg/kg every day for 6 days prior to a Y. pestis Orientalis biotype challenge. Non-challenged, lovastatin-treated and challenged, untreated mice were also used as control groups in the study. Body weight, physical behavior and death were recorded both prior to infection and for 10 days post-infection. Samples of the blood, lungs and spleen were collected from dead mice for direct microbiological examination, histopathology and culture. The potential antibiotic effect of lovastatin was tested on blood agar plates. CONCLUSIONS/SIGNIFICANCE: Lovastatin had no in-vitro antibiotic effect against Y. pestis. The difference in the mortality between control mice (11/15; 73.5% and lovastatin-treated mice (3/15; 20% was significant (P<0.004; Mantel-Haenszel test. Dead mice exhibited Y. pestis septicemia and inflammatory destruction of lung and spleen tissues not seen in lovastatin-treated surviving mice. These data suggest that lovastatin may help prevent the deadly effects of plague. Field observations are warranted to assess the role of lovastatin in the prophylaxis of human plague.

  19. Plague: history and contemporary analysis.

    Science.gov (United States)

    Raoult, Didier; Mouffok, Nadjet; Bitam, Idir; Piarroux, Renaud; Drancourt, Michel

    2013-01-01

    Plague has caused ravaging outbreaks, including the Justinian plague and the "black death" in the Middle Ages. The causative agents of these outbreaks have been confirmed using modern molecular tests. The vector of plague during pandemics remains the subject of controversy. Nowadays, plague must be suspected in all areas where plague is endemic in rodents when patients present with adenitis or with pneumonia with a bloody expectorate. Diagnosis is more difficult in the situation of the reemergence of plague, as in Algeria for example, told by the first physician involved in that outbreak (NM). When in doubt, it is preferable to prescribe treatment with doxycycline while waiting for the test results because of the risk of fatality in individuals with plague. The typical bubo is a type of adenitis that is painful, red and nonfluctuating. The diagnosis is simple when microbiological analysis is conducted. Plague is a likely diagnosis when one sees gram-negative bacilli in lymph node aspirate or biopsy samples. Yersinia pestis grows very easily in blood cultures and is easy to identify by biochemical tests and MALDI-TOF mass spectrometry. Pneumonic plague and septicemic plague without adenitis are difficult to diagnose, and these diagnoses are often made by chance or retrospectively when cases are not part of an epidemic or related to another specific epidemiologic context. The treatment of plague must be based on gentamicin or doxycycline. Treatment with one of these antibiotics must be started as soon as plague is suspected. Analysis of past plague epidemics by using modern laboratory tools illustrated the value of epidemic buboes for the clinical diagnosis of plague; and brought new concepts regarding its transmission by human ectoparasites.

  20. Poultry farms as a source of avian influenza A (H7N9) virus reassortment and human infection.

    Science.gov (United States)

    Wu, Donglin; Zou, Shumei; Bai, Tian; Li, Jing; Zhao, Xiang; Yang, Lei; Liu, Hongmin; Li, Xiaodan; Yang, Xianda; Xin, Li; Xu, Shuang; Zou, Xiaohui; Li, Xiyan; Wang, Ao; Guo, Junfeng; Sun, Bingxin; Huang, Weijuan; Zhang, Ye; Li, Xiang; Gao, Rongbao; Shen, Bo; Chen, Tao; Dong, Jie; Wei, Hejiang; Wang, Shiwen; Li, Qun; Li, Dexin; Wu, Guizhen; Feng, Zijian; Gao, George F; Wang, Yu; Wang, Dayan; Fan, Ming; Shu, Yuelong

    2015-01-15

    Live poultry markets are a source of human infection with avian influenza A (H7N9) virus. On February 21, 2014, a poultry farmer infected with H7N9 virus was identified in Jilin, China, and H7N9 and H9N2 viruses were isolated from the patient's farm. Reassortment between these subtype viruses generated five genotypes, one of which caused the human infection. The date of H7N9 virus introduction to the farm is estimated to be between August 21, 2013 (95% confidence interval [CI] June 6, 2013-October 6, 2013) and September 25, 2013 (95% CI May 28, 2013-January 4, 2014), suggesting that the most likely source of virus introduction was the first batch of poultry purchased in August 2013. The reassortment event that led to the human virus may have occurred between January 2, 2014 (95% CI November 8, 2013-February 12, 2014) and February 12, 2014 (95% CI January 19, 2014-February 18, 2014). Our findings demonstrate that poultry farms could be a source of reassortment between H7N9 virus and H9N2 virus as well as human infection, which emphasizes the importance to public health of active avian influenza surveillance at poultry farms.

  1. Ecologic risk factor investigation of clusters of avian influenza A (H5N1) virus infection in Thailand.

    Science.gov (United States)

    Tiensin, Thanawat; Ahmed, Syed Sayeem Uddin; Rojanasthien, Suvichai; Songserm, Thaweesak; Ratanakorn, Parntep; Chaichoun, Kridsada; Kalpravidh, Wantanee; Wongkasemjit, Surapong; Patchimasiri, Tuangthong; Chanachai, Karoon; Thanapongtham, Weerapong; Chotinan, Suwit; Stegeman, Arjan; Nielen, Mirjam

    2009-06-15

    This study was conducted to investigate space and time clusters of highly pathogenic avian influenza A (H5N1) virus infection and to determine risk factors at the subdistrict level in Thailand. Highly pathogenic avian influenza A (H5N1) was diagnosed in 1890 poultry flocks located in 953 subdistricts during 2004-2007. The ecologic risk for H5N1 virus infection was assessed on the basis of a spatial-based case-control study involving 824 case subdistricts and 3296 control subdistricts from 6 study periods. Risk factors investigated in clustered areas of H5N1 included human and animal demographic characteristics, poultry production systems, and wild birds and their habitats. Six variables remained statistically significant in the final model: flock density of backyard chickens (odds ratio [OR], 0.98), flock density of fighting cocks (OR, 1.02), low and high human density (OR, 0.60), presence of quail flocks (OR, 1.21), free-grazing duck flocks (OR, 2.17), and a poultry slaughterhouse (OR, 1.33). We observed a strong association between subdistricts with H5N1 virus-infected poultry flocks and evidence of prior and concomitant H5N1 infection in wild birds in the same subdistrict.

  2. Highly pathogenic avian influenza virus infection in chickens but not ducks is associated with elevated host immune and pro-inflammatory responses

    NARCIS (Netherlands)

    Kuchipudi, Suresh V; Tellabati, Meenu; Sebastian, Sujith; Londt, Brandon Z; Jansen, Christine; Vervelde, Lonneke; Brookes, Sharon M; Brown, Ian H; Dunham, Stephen P; Chang, Kin-Chow

    2014-01-01

    Highly pathogenic avian influenza (HPAI) H5N1 viruses cause severe infection in chickens at near complete mortality, but corresponding infection in ducks is typically mild or asymptomatic. To understand the underlying molecular differences in host response, primary chicken and duck lung cells, infec

  3. Avian hepatitis E virus infection and possible associated clinical disease in broiler breeder flocks in Hungary.

    Science.gov (United States)

    Morrow, Chris J; Samu, Gyozo; Mátrai, Eszter; Klausz, Akos; Wood, Alasdair M; Richter, Susanne; Jaskulska, Barbara; Hess, Michael

    2008-10-01

    In broiler breeder flocks in one broiler integration in Hungary, a new syndrome appeared in January 2005 with initially four successive post-peak flocks experiencing significant decreases in egg production. Clinically birds became depressed and there was a small increase in the mortality rate. Postmortem examinations revealed enlarged livers in up to 19% of birds dying, and enlarged spleens in some. Also observed were birds with either clotted blood or serosanguineous fluid in the abdomen and subcapsular haemorrhages of the liver. Histopathology and polymerase chain reaction excluded tumours and the presence of common tumour-associated viruses. Chronic bacterial infections (especially causing hepatitis, peritonitis and airsacculitis) were common but many enlarged livers had no obvious bacterial involvement. After a 9-month period during which a majority of flocks became affected, no newly affected flocks occurred. Investigations showed that all tested affected flocks were seropositive in the big liver and spleen (BLS) Agar Gel Immunodiffusion test. Subsequent flocks without post-peak egg-production drops were shown to be seronegative in the BLS AGID test, as were all the parent flocks contributing to the affected flocks. Liver samples and cloacal swabs were positive by polymerase chain reaction (aHEV helicase target), and calicivirus-like particles were demonstrated in bile samples from affected birds. These observations are similar to hepatitis-splenomegaly syndrome as described in North America and BLS syndrome as described in Australia. Histopathological features were a non-specific chronic hepatitis similar to those described in BLS and hepatitis-splenomegaly syndrome. Immunohistochemistry using a BLS-specific monoclonal antibody confirmed the presence of avian hepatitis E virus antigen in livers and spleen.

  4. Experimental and serologic observations on avian pneumovirus (APV/turkey/Colorado/97) infection in turkeys.

    Science.gov (United States)

    Panigrahy, B; Senne, D A; Pedersen, J C; Gidlewski, T; Edson, R K

    2000-01-01

    An avian pneumovirus (APV) was isolated from commercial turkeys in Colorado (APV/Colorado) showing clinical signs of a respiratory disease. The results of virus neutralization and indirect fluorescent antibody tests showed that the APV/Colorado was partially related to APV subgroup A but was unrelated to APV subgroup B. Turkeys experimentally inoculated with the APV/Colorado were observed for signs, lesions, seroconversion, and virus shedding. Thirty-six 7-wk-old turkeys were distributed into three groups. Eighteen turkeys were inoculated oculonasally with APV/Colorado, six were placed in contact at 1 day postinoculation (DPI), and 12 served as noninoculated controls. Tracheal swabs and blood samples were collected at 3, 5, 7, 10, 14, and 21 DPI. Tissues were collected from three inoculated and two control turkeys on aforementioned days for pathologic examination and APV isolation. Inoculated turkeys developed respiratory disease, yielded APV at 3, 5, and 7 DPI, and seroconverted at 10 DPI. Contact turkeys yielded APV at 7 and 10 DPI. No gross lesions were observed in the turbinates, infraorbital sinuses, and trachea. However, microscopic examination revealed acute rhinitis, sinusitis, and tracheitis manifested by congestion, edema, lymphocytic and heterophilic infiltration, and loss of ciliated epithelia. The inflammatory lesions were seen at 3 DPI and became extensive at 5 and 7 DPI. Active regenerative changes in the epithelia were seen at 10 and 14 DPI. Serologic survey for the presence of antibodies in commercial turkeys (24,504 sera from 18 states) and chickens (3,517 sera from 12 states) to APV/Colorado showed seropositive turkeys in Minnesota, North Dakota, and South Dakota and no seropositive chickens. This report is the first on the isolation of an APV and APV infection in the United States.

  5. Differential expression of immune-related cytokine genes in response to J group avian leukosis virus infection in vivo.

    Science.gov (United States)

    Gao, Yanni; Liu, Yongzhen; Guan, Xiaolu; Li, Xiaofei; Yun, Bingling; Qi, Xiaole; Wang, Yongqiang; Gao, Honglei; Cui, Hongyu; Liu, Changjun; Zhang, Yanping; Wang, Xiaomei; Gao, Yulong

    2015-03-01

    Infection with J group avian leukosis virus (ALV-J) can result in immunosuppression and subsequently increased susceptibility to secondary infection. The innate immune system is the first line defense system in prevention of further bacterial and viral infections. Cytokines play key roles in the innate immune system. In this study, we used RT-qPCR technology to test the cytokine mRNA expression levels in various immune tissues, including the spleen, bursa of fabricius and cecal tonsil, in the days following ALV-J infection. The results indicated that in the infected group, the expression levels of interleukin-6 (IL-6), IL-18, interferon-α (IFN-α) and IFN-γ significantly increased in the spleen and reached peak levels that were thousandfolds higher than baselines at 9-12 days post-infection (d.p.i.). The levels in the bursa of fabricius slightly increased, and the levels in the cecal tonsil were not significantly altered. Moreover, the pattern of the expression of these three cytokines in the spleens of the infected group was similar to the pattern of viremia of this group. These results suggest that the spleen plays an important role in the interaction between ALV-J infection and the innate immune system. This study contributes to the understanding of innate immune responses to ALV-J infection and also elucidates the mechanisms of the pathogenicity of ALV-J in chickens.

  6. Intervention strategies to reduce the risk of zoonotic infection with avian influenza viruses: scientific basis, challenges and knowledge gaps.

    Science.gov (United States)

    Sims, Leslie D

    2013-09-01

    A range of measures has been recommended and used for the control and prevention of avian influenza. These measures are based on the assessment of local epidemiological situations, field observations and other scientific information. Other non-technical factors are (or in some cases should be) taken into account when developing and recommending control measures. The precise effects under field conditions of most individual interventions applied to control and prevent avian influenza have not been established or subjected to critical review, often because a number of measures are applied simultaneously without controls. In most cases, the combination of measures used results in control or elimination of the virus although there are some countries where this has not been the case. In others, especially those with low poultry density, it is not clear whether the link between the adoption of a set of measures and the subsequent control of the disease is causative. This article discusses the various measures recommended, with particular emphasis on stamping out and vaccination, examines how these measures assist in preventing zoonotic infections with avian influenza viruses and explores gaps in knowledge regarding their effectiveness.

  7. Effects of infection-induced migration delays on the epidemiology of avian influenza in wild mallard populations.

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    Stephen J Galsworthy

    Full Text Available Wild waterfowl populations form a natural reservoir of Avian Influenza (AI virus, and fears exist that these birds may contribute to an AI pandemic by spreading the virus along their migratory flyways. Observational studies suggest that individuals infected with AI virus may delay departure from migratory staging sites. Here, we explore the epidemiological dynamics of avian influenza virus in a migrating mallard (Anas platyrhynchos population with a specific view to understanding the role of infection-induced migration delays on the spread of virus strains of differing transmissibility. We develop a host-pathogen model that combines the transmission dynamics of influenza with the migration, reproduction and mortality of the host bird species. Our modeling predicts that delayed migration of individuals influences both the timing and size of outbreaks of AI virus. We find that (1 delayed migration leads to a lower total number of cases of infection each year than in the absence of migration delay, (2 when the transmission rate of a strain is high, the outbreak starts at the staging sites at which birds arrive in the early part of the fall migration, (3 when the transmission rate is low, infection predominantly occurs later in the season, which is further delayed when there is a migration delay. As such, the rise of more virulent AI strains in waterfowl could lead to a higher prevalence of infection later in the year, which could change the exposure risk for farmed poultry. A sensitivity analysis shows the importance of generation time and loss of immunity for the effect of migration delays. Thus, we demonstrate, in contrast to many current transmission risk models solely using empirical information on bird movements to assess the potential for transmission, that a consideration of infection-induced delays is critical to understanding the dynamics of AI infection along the entire flyway.

  8. Cellular transcripts regulated during infections with Highly Pathogenic H5N1 Avian Influenza virus in 3 host systems

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    Noor Suriani M

    2011-04-01

    Full Text Available Abstract Background Highly pathogenic Avian Influenza (HPAI virus is able to infect many hosts and the virus replicates in high levels in the respiratory tract inducing severe lung lesions. The pathogenesis of the disease is actually the outcome of the infection as determined by complex host-virus interactions involving the functional kinetics of large numbers of participating genes. Understanding the genes and proteins involved in host cellular responses are therefore, critical for the elucidation of the mechanisms of infection. Methods Differentially expressed transcripts regulated in a H5N1 infections of whole lung organ of chicken, in-vitro chick embryo lung primary cell culture (CeLu and a continuous Madin Darby Canine Kidney cell line was undertaken. An improved mRNA differential display technique (Gene Fishing™ using annealing control primers that generates reproducible, authentic and long PCR products that are detectable on agarose gels was used for the identification of differentially expressed genes (DEGs. Seven of the genes have been selected for validation using a TaqMan® based real time quantitative PCR assay. Results Thirty seven known and unique differentially expressed genes from lungs of chickens, CeLu and MDCK cells were isolated. Among the genes isolated and identified include heat shock proteins, Cyclin D2, Prenyl (decaprenyl diphosphate synthase, IL-8 and many other unknown genes. The quantitative real time RT-PCR assay data showed that the transcription kinetics of the selected genes were clearly altered during infection by the Highly Pathogenic Avian Influenza virus. Conclusion The Gene Fishing™ technique has allowed for the first time, the isolation and identification of sequences of host cellular genes regulated during H5N1 virus infection. In this limited study, the differentially expressed genes in the three host systems were not identical, thus suggesting that their responses to the H5N1 infection may not share

  9. Pathobiology of highly pathogenic avian influenza virus H5N2 infection in juvenile ostriches from South Africa.

    Science.gov (United States)

    Howerth, Elizabeth W; Olivier, Adriaan; França, Monique; Stallknecht, David E; Gers, Sophette

    2012-12-01

    In 2011, over 35,000 ostriches were slaughtered in the Oudtshoorn district of the Western Cape province of South Africa following the diagnosis of highly pathogenic avian influenza virus H5N2. We describe the pathology and virus distribution via immunohistochemistry in juvenile birds that died rapidly in this outbreak after showing signs of depression and weakness. Associated sialic acid (SA) receptor distribution in uninfected birds is also described. At necropsy, enlarged spleens, swollen livers, and generalized congestion were noted. Birds not succumbing to acute influenza infection often became cachectic with serous atrophy of fat, airsacculitis, and secondary infections. Necrotizing hepatitis, splenitis, and airsacculitis were prominent histopathologic findings. Virus was detected via immunohistochemistry in abundance in the liver and spleen but also in the air sac and gastrointestinal tract. Infected cells included epithelium, endothelium, macrophages, circulating leukocytes, and smooth muscle of a variety of organs and vessel walls. Analysis of SA receptor distribution in uninfected juvenile ostriches via lectin binding showed abundant expression of SAalpha2,3Gal (avian type) and little or no expression of SAalpha2,6Gal (human type) in the gastrointestinal and respiratory tracts, as well as leukocytes in the spleen and endothelial cells in all organs, which correlated with H5N2 antigen distribution in these tissues.

  10. Imaging manifestations and pathological analysis of severe pneumonia caused by human infected avian influenza (H7N9

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    Zheng Zeng

    2015-03-01

    Conclusion: The imaging features of severe pneumonia caused by human infected avian influenza (H7N9 include obvious ground-glass opacity and pulmonary consolidation, mainly at lower lobes and dorsal of lungs, with rapid changes. The cross-analysis of imaging and pathology preliminary can elucidate the pathological mechanisms of ground-glass opacities and pulmonary consolidation of severe pneumonia. Such an intensive study is beneficial to prompt clinicians to observe and evaluate the progress of the disease. In addition, it is also in favor of managing the symptoms and reducing the mortality rate.

  11. Subgroup J avian leukosis virus infection of chicken dendritic cells induces apoptosis via the aberrant expression of microRNAs.

    Science.gov (United States)

    Liu, Di; Dai, Manman; Zhang, Xu; Cao, Weisheng; Liao, Ming

    2016-02-01

    Subgroup J avian leukosis virus (ALV-J) is an oncogenic retrovirus that causes immunosuppression and enhances susceptibility to secondary infection. The innate immune system is the first line of defense in preventing bacterial and viral infections, and dendritic cells (DCs) play important roles in innate immunity. Because bone marrow is an organ that is susceptible to ALV-J, the virus may influence the generation of bone marrow-derived DCs. In this study, DCs cultured in vitro were used to investigate the effects of ALV infection. The results revealed that ALV-J could infect these cells during the early stages of differentiation, and infection of DCs with ALV-J resulted in apoptosis. miRNA sequencing data of uninfected and infected DCs revealed 122 differentially expressed miRNAs, with 115 demonstrating upregulation after ALV-J infection and the other 7 showing significant downregulation. The miRNAs that exhibited the highest levels of upregulation may suppress nutrient processing and metabolic function. These results indicated that ALV-J infection of chicken DCs could induce apoptosis via aberrant microRNA expression. These results provide a solid foundation for the further study of epigenetic influences on ALV-J-induced immunosuppression.

  12. Paleoclimate and bubonic plague: a forewarning of future risk?

    Science.gov (United States)

    McMichael, Anthony J

    2010-08-27

    Pandemics of bubonic plague have occurred in Eurasia since the sixth century AD. Climatic variations in Central Asia affect the population size and activity of the plague bacterium's reservoir rodent species, influencing the probability of human infection. Using innovative time-series analysis of surrogate climate records spanning 1,500 years, a study in BMC Biology concludes that climatic fluctuations may have influenced these pandemics. This has potential implications for health risks from future climate change.

  13. The PI3K/Akt pathway is involved in early infection of some exogenous avian leukosis viruses.

    Science.gov (United States)

    Feng, Shao-zhen; Cao, Wei-sheng; Liao, Ming

    2011-07-01

    Avian leukosis virus (ALV) is an enveloped and oncogenic retrovirus. Avian leukosis caused by the members of ALV subgroups A, B and J has become one of the major problems challenging the poultry industry in China. However, the cellular factors such as signal transduction pathways involved in ALV infection are not well defined. In this study, our data demonstrated that ALV-J strain NX0101 infection in primary chicken embryo fibroblasts or DF-1 cells was correlated with the activity and phosphorylation of Akt. Akt activation was initiated at a very early stage of infection independently of NX0101 replication. The specific phosphatidylinositol 3-kinase (PI3K) inhibitors LY294002 or wortmannin could suppress Akt phosphorylation, indicating that NX0101-induced Akt phosphorylation is PI3K-dependent. ALV-A strain GD08 or ALV-B strain CD08 infection also demonstrated a similar profile of PI3K/Akt activation. Treatment of DF-1 cells with the drug 5-(N, N-hexamethylene) amiloride that inhibits the activity of chicken Na(+)/H(+) exchanger type 1 significantly reduced Akt activation induced by NX0101, but not by GD08 and CD08. Akt activation triggered by GD08 or CD08 was abolished by clathrin-mediated endocytosis inhibitor chlorpromazine. Receptor-mediated endocytosis inhibitor dansylcadaverine had a negligible effect on all ALV-induced Akt phosphorylation. Moreover, viral replication of ALV was suppressed by LY294002 in a dose-dependent manner, which was due to the inhibition of virus infection by LY294002. These data suggest that the activation of the PI3K/Akt signalling pathway by exogenous ALV infection plays an important role in viral entry, yet the precise mechanism remains under further investigation.

  14. Plague and climate: scales matter.

    Directory of Open Access Journals (Sweden)

    Tamara Ben-Ari

    2011-09-01

    Full Text Available Plague is enzootic in wildlife populations of small mammals in central and eastern Asia, Africa, South and North America, and has been recognized recently as a reemerging threat to humans. Its causative agent Yersinia pestis relies on wild rodent hosts and flea vectors for its maintenance in nature. Climate influences all three components (i.e., bacteria, vectors, and hosts of the plague system and is a likely factor to explain some of plague's variability from small and regional to large scales. Here, we review effects of climate variables on plague hosts and vectors from individual or population scales to studies on the whole plague system at a large scale. Upscaled versions of small-scale processes are often invoked to explain plague variability in time and space at larger scales, presumably because similar scale-independent mechanisms underlie these relationships. This linearity assumption is discussed in the light of recent research that suggests some of its limitations.

  15. Plague and climate: scales matter.

    Science.gov (United States)

    Ben-Ari, Tamara; Ben Ari, Tamara; Neerinckx, Simon; Gage, Kenneth L; Kreppel, Katharina; Laudisoit, Anne; Leirs, Herwig; Stenseth, Nils Chr

    2011-09-01

    Plague is enzootic in wildlife populations of small mammals in central and eastern Asia, Africa, South and North America, and has been recognized recently as a reemerging threat to humans. Its causative agent Yersinia pestis relies on wild rodent hosts and flea vectors for its maintenance in nature. Climate influences all three components (i.e., bacteria, vectors, and hosts) of the plague system and is a likely factor to explain some of plague's variability from small and regional to large scales. Here, we review effects of climate variables on plague hosts and vectors from individual or population scales to studies on the whole plague system at a large scale. Upscaled versions of small-scale processes are often invoked to explain plague variability in time and space at larger scales, presumably because similar scale-independent mechanisms underlie these relationships. This linearity assumption is discussed in the light of recent research that suggests some of its limitations.

  16. Development of Rapid Immunochromatographic Test for Hemagglutinin Antigen of H7 Subtype in Patients Infected with Novel Avian Influenza A (H7N9) Virus

    OpenAIRE

    Keren Kang; Li Chen; Xiang Zhao; Chengfeng Qin; Zanwu Zhan; Jihua Wang; Wenmei Li; Emmanuel E. Dzakah; Weijuang Huang; Yuelong Shu; Tao Jiang; Wuchun Cao; Mingquan Xie; Xiaochun Luo; Shixing Tang

    2014-01-01

    BACKGROUND: Since human infection with the novel H7N9 avian influenza virus was identified in China in March 2013, the relatively high mortality rate and possibility of human-to-human transmission have highlighted the urgent need for sensitive and specific assays for diagnosis of H7N9 infection. METHODOLOGY/PRINCIPAL FINDINGS: We developed a rapid diagnostic test for the novel avian influenza A (H7N9) virus using anti-hemagglutinin (HA) monoclonal antibodies specifically targeting H7 in an im...

  17. Natural Infection with Avian Hepatitis E Virus and Marek's Disease Virus in Brown Layer Chickens in China.

    Science.gov (United States)

    Yang, Shuqing; Wang, Liyuan; Sun, Shuhong

    2016-09-01

    In the present study, avian hepatitis E virus (HEV) and serotype-1 strains of Marek's disease virus (MDV-1) were detected from a flock of 27-wk-old brown layer hens in China, accompanied by an average daily mortality of 0.44%. Postmortem examination of 25 sick hens and five apparently healthy hens selected randomly from the flock showed significant pathologic changes consistent with hepatitis-splenomegaly syndrome (HSS), including hepatomegaly, peritoneal fluid, and hepatic subcapsular hemorrhages. Microscopic examination of these livers showed multifocal necrotizing hepatitis and mild lymphocytic infiltration. These liver samples were investigated for HEV by reverse-transcription PCR. The overall detection rate of HEV RNA in samples of sick chickens was about 56% (14/25), while in samples from apparently healthy hens, it was 80% (4/5). Sequencing analysis of three 242-base-pair fragments of the helicase gene revealed 95.5% to 97.9% nucleotide identity compared with published avian HEV genotype 3, whereas identities demonstrated only 77.3% to 86.0% similarity when compared with genotypes 1, 2, and 4. Unexpectedly, the MDV meq gene was detected in livers from both apparently healthy chickens (2/5) and sick chickens (12/25) by PCR analysis. The meq gene (396 base pairs) was determined to belong to MDV-1 by further sequencing. The co-infection rate of avian HEV and MDV in this flock was 30% (9/30). This is the first report of dual infection of a nonenvelope RNA virus (HEV) with a herpesvirus (MDV) in chickens in China.

  18. Aberrant expression of liver microRNA in chickens infected with subgroup J avian leukosis virus

    Science.gov (United States)

    Subgroup J avian leukosis virus (ALV-J) is an oncogenic retrovirus primarily causing myeloid leukosis (ML) in broilers. Although ALV is well under control in a few countries including the U.S.A., poultry industry in many parts of the world continues suffering from serious economic loss due to sporad...

  19. Gene expression changes in chicken NLRC5 signal pathway associated with in vitro avian leukosis virus subgroup J infection.

    Science.gov (United States)

    Qiu, L L; Xu, L; Guo, X M; Li, Z T; Wan, F; Liu, X P; Chen, G H; Chang, G B

    2016-03-18

    Nucleotide-binding oligomerization domain-like receptors (NLRs) play a key role in the innate immune response as pattern-recognition receptors. However, the role of NLRC5, which is a member of the NLR family, in NF-κB activation and MHC-I expression remains debatable. Infection with the J group avian leukosis virus (ALV-J) can result in immunosuppression and a subsequent increase in susceptibility to secondary infection. This results in huge economic losses to the poultry industry worldwide. Using quantitative real-time polymerase chain reaction (qRT-PCR), we investigated the mRNA expression levels of NLRC5 signal pathway-related genes in secondary chicken embryo fibroblasts 7 days after infection with ALV-J. The results indicated that, compared with the control groups, the expression levels of TLR7, MHC-I, and IL-18 increased significantly in the infected groups at 7 days post-infection (d.p.i.). The expression levels of NLRC5 and IL-6 were conspicuously downregulated at 7 d.p.i., but the expression levels of NF-κB, STAT1, and STAT3 were not significantly altered. These results suggest that NLRC5 and some genes involved in the NLRC5 pathway play a key role in antiviral immunity, typically the response to ALV-J infection. Moreover, MHC-I expression levels vary between different cell types.

  20. Infectivity and pathogenicity of Newcastle disease virus strains of different avian origin and different virulence for mallard ducklings.

    Science.gov (United States)

    Dai, Yabin; Liu, Mei; Cheng, Xu; Shen, Xinyue; Wei, Yuyong; Zhou, Sheng; Yu, Shengqing; Ding, Chan

    2013-03-01

    Experimental infections of Newcastle disease virus (NDV) strains of different avian origin and different virulence in mallard (Anas platyrhynchos) ducklings were undertaken to evaluate infectivity and pathogenicity of NDV for ducks and the potential role of ducks in the epidemiology of Newcastle disease (ND). Ducklings were experimentally infected with seven NDV strains, and their clinical sign, weight gain, antibody response, virus shedding, and virus distribution in tissues were investigated. The duck origin virulent strain duck/Jiangsu/JSD0812/2008 (JSD0812) and the Chinese standard virulent strain F48E8 were highly pathogenic for ducklings. They caused high morbidity and mortality, and they distributed extensively in various tissues of infected ducklings. Other strains, including pigeon origin virulent strain pigeon/Jiangsu/JSP0204/2002 (JSP0204), chicken origin virulent strain chicken/Jiangsu/JSC0804/2008 (JSC0804), goose origin virulent goose/Jiangsu/JSG0210/2002 (JSG0210), and vaccine strains Mukteswar and LaSota had no pathogenicity to ducklings. They produced neither clinical signs of the disease nor adverse effect on growth of infected ducklings, and they persisted in duck bodies for only a short period. Virus shedding was detectable in all infected ducklings, but its period and route varied with the virulence of NDV strains. The results suggest that NDV with high pathogenicity in ducks may arise from the evolution within its corresponding host, further confirming that the ducks play an important role in the epidemiology of ND.

  1. Infections and reinfections with avian pneumovirus subtype A and B on Belgian turkey farms and relation to respiratory problems.

    Science.gov (United States)

    Van de Zande, S; Nauwynck, H; Cavanagh, D; Pensaert, M

    1998-12-01

    A longitudinal study was performed on six turkey farms in order to determine whether infections with avian pneumovirus (APV) occur and if they are related to outbreaks of respiratory problems in Belgium. Blood was taken at 1-3 week intervals of 20 identified animals during the fattening period. On five farms, the turkeys seroconverted against APV shortly after the appearance of respiratory problems. On two farms, where the animals had not been vaccinated against APV, attempts were made to isolate APV during the outbreaks. Two isolates were obtained: one of subtype A, the other of subtype B. These results indicate that the respiratory problems on five farms were related to an infection with APV. A second increase in APV antibody titres detected on four farms at the end of the fattening period, indicates that reinfections frequently occur. This is, to our knowledge, the first report on the isolation of an APV subtype A on the continent.

  2. Understanding the persistence of plague foci in Madagascar.

    Science.gov (United States)

    Andrianaivoarimanana, Voahangy; Kreppel, Katharina; Elissa, Nohal; Duplantier, Jean-Marc; Carniel, Elisabeth; Rajerison, Minoarisoa; Jambou, Ronan

    2013-11-01

    Plague, a zoonosis caused by Yersinia pestis, is still found in Africa, Asia, and the Americas. Madagascar reports almost one third of the cases worldwide. Y. pestis can be encountered in three very different types of foci: urban, rural, and sylvatic. Flea vector and wild rodent host population dynamics are tightly correlated with modulation of climatic conditions, an association that could be crucial for both the maintenance of foci and human plague epidemics. The black rat Rattus rattus, the main host of Y. pestis in Madagascar, is found to exhibit high resistance to plague in endemic areas, opposing the concept of high mortality rates among rats exposed to the infection. Also, endemic fleas could play an essential role in maintenance of the foci. This review discusses recent advances in the understanding of the role of these factors as well as human behavior in the persistence of plague in Madagascar.

  3. Understanding the persistence of plague foci in Madagascar.

    Directory of Open Access Journals (Sweden)

    Voahangy Andrianaivoarimanana

    2013-11-01

    Full Text Available Plague, a zoonosis caused by Yersinia pestis, is still found in Africa, Asia, and the Americas. Madagascar reports almost one third of the cases worldwide. Y. pestis can be encountered in three very different types of foci: urban, rural, and sylvatic. Flea vector and wild rodent host population dynamics are tightly correlated with modulation of climatic conditions, an association that could be crucial for both the maintenance of foci and human plague epidemics. The black rat Rattus rattus, the main host of Y. pestis in Madagascar, is found to exhibit high resistance to plague in endemic areas, opposing the concept of high mortality rates among rats exposed to the infection. Also, endemic fleas could play an essential role in maintenance of the foci. This review discusses recent advances in the understanding of the role of these factors as well as human behavior in the persistence of plague in Madagascar.

  4. Plague in Arab Maghreb, 1940–2015: A Review

    Science.gov (United States)

    Malek, Maliya Alia; Bitam, Idir; Drancourt, Michel

    2016-01-01

    We reviewed the epidemiology of 49 plague outbreaks that resulted in about 7,612 cases in 30 localities in the Arabic Maghreb (Mauritania, Morocco, Algeria, Tunisia, Libya, and Egypt) over 75 years. Between 1940 and 1950, most cases recorded in Morocco (75%) and Egypt (20%), resulted from plague imported to Mediterranean harbors and transmitted by rat ectoparasites. By contrast, the re-emergence of plague in the southern part of Western Sahara in 1953 and in northeast Libya in 1976 was traced to direct contact between nomadic populations and infected goats and camels in natural foci, including the consumption of contaminated meat, illustrating this neglected oral route of contamination. Further familial outbreaks were traced to human ectoparasite transmission. Efforts to identify the factors contributing to natural foci may guide where to focus the surveillance of sentinel animals in order to eradicate human plague, if not Yersinia pestis from the Arab Maghreb. PMID:27376053

  5. The Formula of Plague Narratives

    DEFF Research Database (Denmark)

    Christensen, Jørgen Riber

    2015-01-01

    and fictional, of epidemics. The samples include: Exodus, History of the Peloponnesian War, Samuel Pepys’ Diary, A Journal of the Plague Year, The Last Man, The Plague in Bergamo, Discipline and Punish: The Birth of the Prison, Doomsday, The Dead Zone, World War Z. An Oral History of the Zombie War, Pandemic...

  6. Avian haemosporidian parasites (Haemosporida): A comparative analysis of different polymerase chain reaction assays in detection of mixed infections.

    Science.gov (United States)

    Bernotienė, Rasa; Palinauskas, Vaidas; Iezhova, Tatjana; Murauskaitė, Dovilė; Valkiūnas, Gediminas

    2016-04-01

    Mixed infections of different species and genetic lineages of haemosporidian parasites (Haemosporida) predominate in wildlife, and such infections are particularly virulent. However, currently used polymerase chain reaction (PCR)-based detection methods often do not read mixed infections. Sensitivity of different PCR assays in detection of mixed infections has been insufficiently tested, but this knowledge is essential in studies addressing parasite diversity in wildlife. Here, we applied five different PCR assays, which are broadly used in wildlife avian haemosporidian research, and compared their sensitivity in detection of experimentally designed mixed infections of Haemoproteus and Plasmodium parasites. Three of these PCR assays use primer sets that amplify fragments of cytochrome b gene (cyt b), one of cytochrome oxidase subunit I (COI) gene, and one target apicoplast genome. We collected blood from wild-caught birds and, using microscopic and PCR-based methods applied in parallel, identified single infections of ten haemosporidian species with similar parasitemia. Then, we prepared 15 experimental mixes of different haemosporidian parasites, which often are present simultaneously in wild birds. Similar concentration of total DNA was used in each parasite lineage during preparation of mixes. Positive amplifications were sequenced, and the presence of mixed infections was reported by visualising double-base calling in sequence electropherograms. This study shows that the use of each single PCR assay markedly underestimates biodiversity of haemosporidian parasites. The application of at least 3 PCR assays in parallel detected the majority, but still not all lineages present in mixed infections. We determined preferences of different primers in detection of parasites belonging to different genera of haemosporidians during mixed infections.

  7. Integrated analysis of microRNA expression and mRNA transcriptome in lungs of avian influenza virus infected broilers

    Directory of Open Access Journals (Sweden)

    Wang Ying

    2012-06-01

    Full Text Available Abstract Background Avian influenza virus (AIV outbreaks are worldwide threats to both poultry and humans. Our previous study suggested microRNAs (miRNAs play significant roles in the regulation of host response to AIV infection in layer chickens. The objective of this study was to test the hypothesis if genetic background play essential role in the miRNA regulation of AIV infection in chickens and if miRNAs that were differentially expressed in layer with AIV infection would be modulated the same way in broiler chickens. Furthermore, by integrating with parallel mRNA expression profiling, potential molecular mechanisms of host response to AIV infection can be further exploited. Results Total RNA isolated from the lungs of non-infected and low pathogenic H5N3 infected broilers at four days post-infection were used for both miRNA deep sequencing and mRNA microarray analyses. A total of 2.6 M and 3.3 M filtered high quality reads were obtained from infected and non-infected chickens by Solexa GA-I Sequencer, respectively. A total of 271 miRNAs in miRBase 16.0 were identified and one potential novel miRNA was discovered. There were 121 miRNAs differentially expressed at the 5% false discovery rate by Fisher’s exact test. More miRNAs were highly expressed in infected lungs (108 than in non-infected lungs (13, which was opposite to the findings in layer chickens. This result suggested that a different regulatory mechanism of host response to AIV infection mediated by miRNAs might exist in broiler chickens. Analysis using the chicken 44 K Agilent microarray indicated that 508 mRNAs (347 down-regulated were differentially expressed following AIV infection. Conclusions A comprehensive analysis combining both miRNA and targeted mRNA gene expression suggests that gga-miR-34a, 122–1, 122–2, 146a, 155, 206, 1719, 1594, 1599 and 451, and MX1, IL-8, IRF-7, TNFRS19 are strong candidate miRNAs or genes involved in regulating the host response to AIV

  8. AFLP genome scan in the black rat (Rattus rattus) from Madagascar: detecting genetic markers undergoing plague-mediated selection.

    Science.gov (United States)

    Tollenaere, C; Duplantier, J-M; Rahalison, L; Ranjalahy, M; Brouat, C

    2011-03-01

    The black rat (Rattus rattus) is the main reservoir of plague (Yersinia pestis infection) in Madagascar's rural zones. Black rats are highly resistant to plague within the plague focus (central highland), whereas they are susceptible where the disease is absent (low altitude zone). To better understand plague wildlife circulation and host evolution in response to a highly virulent pathogen, we attempted to determine genetic markers associated with plague resistance in this species. To this purpose, we combined a population genomics approach and an association study, both performed on 249 AFLP markers, in Malagasy R. rattus. Simulated distributions of genetic differentiation were compared to observed data in four independent pairs, each consisting of one population from the plague focus and one from the plague-free zone. We found 22 loci (9% of 249) with higher differentiation in at least two independent population pairs or with combining P-values over the four pairs significant. Among the 22 outlier loci, 16 presented significant association with plague zone (plague focus vs. plague-free zone). Population genetic structure inferred from outlier loci was structured by plague zone, whereas the neutral loci dataset revealed structure by geography (eastern vs. western populations). A phenotype association study revealed that two of the 22 loci were significantly associated with differentiation between dying and surviving rats following experimental plague challenge. The 22 outlier loci identified in this study may undergo plague selective pressure either directly or more probably indirectly due to hitchhiking with selected loci.

  9. Previous infection with virulent strains of Newcastle disease virus reduces highly pathogenic avian influenza virus replication, disease, and mortality in chickens

    Science.gov (United States)

    Avian influenza virus (AIV) and Newcastle disease virus (NDV) are two of the most important viruses affecting poultry worldwide, but little is known about the interaction between these two viruses when simultaneously co-infecting the same host, especially in areas of the world where both viruses are...

  10. Effect of an in ovo infection with a Dutch avian leukosis virus subgroup J isolate on the growth and immunological performance of SPF broiler chickens

    NARCIS (Netherlands)

    Landman, W.J.M.; Post, J.; Boonstra Blom, A.G.; Buyse, J.; Elbers, A.R.W.; Koch, G.

    2002-01-01

    The effect of an in ovo infection with a Dutch isolate of avian leukosis virus subgroup J (ALV-J) on the growth of specific pathogen free (SPF) broiler chickens was analysed. During this study, possible immune suppressive effects of ALV-J were assessed by measuring delayed-type hypersensitivity with

  11. Histopathological characterization and shedding dynamics of guineafowl (Numida meleagris) intravenously infected with a H6N2 low pathogenicity Avian Influenza virus

    Science.gov (United States)

    Guineafowl of different ages were inoculated intravenously with an H6N2 wild waterfowl-origin low-pathogenicity type A avian influenza virus (LPAI). No evidence of clinical disease was observed. The examined infected birds had atrophy of the spleen, thymus, and cloacal bursa when compared to the n...

  12. Experimental infection with low and high pathogenicity H7N3 Chilean avian influenza viruses in Chiloe Wigeon (Anas sibilatrix) and Cinnamon Teal (Anas cyanoptera)

    Science.gov (United States)

    Since 2002, H5N1 high pathogenicity avian influenza (HPAI) viruses have been associated with natural, lethal infections in wild aquatic birds which have been reproduced experimentally. Some aquatic bird species have been suggested as potential transporters of H5N1 HPAI virus via migration. However, ...

  13. First natural infection by Ascocotyle (Phagicola longa Ransom (Digenea, Heterophyidae in an avian host, Ardea cocoi Linnaeus (Aves, Ciconiiformes, Ardeidae in Brazil

    Directory of Open Access Journals (Sweden)

    Luciano Antunes Barros

    2002-03-01

    Full Text Available The first case of a natural avian infection caused by the digenetic trematode Ascocotyle (Phagicola longa Ransom, 1920 in Brazil, is reported from the ardeid bird Ardea cocoi Linnaeus, 1766. This represents a new host record and data on clinical and pathological findings are also reported.

  14. A cross-sectional serological survey of the Dutch commercial poultry population for the presence of Low Pathogenic Avian Influenza virus infection

    NARCIS (Netherlands)

    Wit, de J.J.; Koch, G.; Fabri, T.H.F.; Elbers, A.R.W.

    2004-01-01

    After the discovery of poultry infected with highly pathogenic avian influenza (HPAI) virus of subtype H7N7 in the central area of the Netherlands on 28 February 2003, the hypothesis was put forward that an outbreak of the low pathogenic (LP) variant of H7N7 had preceded, unnoticed, the occurrence o

  15. Highly pathogenic avian influenza virus H5N1 infection in a long-distance migrant shorebird under migratory and non-migratory states

    NARCIS (Netherlands)

    Reperant, Leslie A.; Bildt, Marco W.G. van de; Amerongen, Geert van; Buehler, Deborah; Osterhaus, Albert D.M.E.; Jenni-Eiermann, Susi; Piersma, Theunis; Kuiken, Thijs

    2011-01-01

    Corticosterone regulates physiological changes preparing wild birds for migration. It also modulates the immune system and may lead to increased susceptibility to infection, with implications for the spread of pathogens, including highly pathogenic avian influenza virus (HPAIV) H5N1. The red knot (C

  16. Highly pathogenic avian influenza virus H5N1 infection in a long-distance migrant shorebird under migratory and non-migratory states

    NARCIS (Netherlands)

    L.A. Reperant (Leslie); M.W.G. van de Bildt (Marco); G. van Amerongen (Geert); D.M. Buehler (Debbie); A.D.M.E. Osterhaus (Albert); S. Jenni-Eiermann (Susi); T. Piersma (Theunis); T. Kuiken (Thijs)

    2011-01-01

    textabstractCorticosterone regulates physiological changes preparing wild birds for migration. It also modulates the immune system and may lead to increased susceptibility to infection, with implications for the spread of pathogens, including highly pathogenic avian influenza virus (HPAIV) H5N1. The

  17. Highly Pathogenic Avian Influenza Virus H5N1 Infection in a Long-Distance Migrant Shorebird under Migratory and Non-Migratory States

    NARCIS (Netherlands)

    Reperant, L.A.; van de Bildt, M.W.G.; van Amerongen, G.; Buehler, D.M.; Osterhaus, A.D.M.E.; Jenni-Eiermann, S.; Piersma, T.; Kuiken, T.

    2011-01-01

    Corticosterone regulates physiological changes preparing wild birds for migration. It also modulates the immune system and may lead to increased susceptibility to infection, with implications for the spread of pathogens, including highly pathogenic avian influenza virus (HPAIV) H5N1. The red knot (C

  18. Widespread avian bornavirus infection in mute swans in the Northeast United States

    Directory of Open Access Journals (Sweden)

    Payne SL

    2012-07-01

    Full Text Available Jianhua Guo,1 Lina Covaleda,1 J Jill Heatley,1 John A Baroch,2 Ian Tizard1, Susan L Payne,11Texas A&M University, College Station, TX, USA; 2USDA/APHIS Wildlife Services, Fort Collins, CO, USAAbstract: Avian bornavirus (ABV matrix (M genes were detected by RT-PCR on brain tissue obtained from 192 mute swans harvested from several Northeastern states. A RT-PCR product was detected in 45 samples. Sequencing of the PCR products confirmed the presence of ABV belonging to the ‘goose’ genotype. The prevalence of positive samples ranged from 28% in Michigan to 0% in northern New York State. Two Rhode Island isolates were cultured. Their M, N, and X-P gene sequences closely matched recently published sequences from Canada geese.Keywords: avian bornavirus, proventricular dilatation disease, reverse transcription, polymerase chain reaction, mute swans

  19. Profiles of acute cytokine and antibody responses in patients infected with avian influenza A H7N9.

    Directory of Open Access Journals (Sweden)

    Rui Huang

    Full Text Available The influenza A H7N9 virus outbreak in Eastern China in the spring of 2013 represented a novel, emerging avian influenza transmission to humans. While clinical and microbiological features of H7N9 infection have been reported in the literature, the current study investigated acute cytokine and antibody responses in acute H7N9 infection. Between March 27, 2013 and April 23, 2013, six patients with confirmed H7N9 influenza infection were admitted to Drum Tower Hospital, Nanjing, China. Acute phase serum cytokine profiles were determined using a high-throughput multiplex assay. Daily H7 hemagglutinin (HA-specific IgG, IgM, and IgA responses were monitored by ELISA. Neutralizing antibodies specific for H7N9 viruses were determined against a pseudotyped virus expressing the novel H7 subtype HA antigen. Five cytokines (IL-6, IP-10, IL-10, IFNγ, and TNFα were significantly elevated in H7N9-infected patients when compared to healthy volunteers. Serum H7 HA-specific IgG, as well as IgM and IgA responses, were detected within 8 days of disease onset and increased in a similar pattern during acute infection. Neutralizing antibodies developed shortly after the appearance of binding antibody responses and showed similar kinetics as a fraction of the total H7 HA-specific IgG responses. H7N9 infection resulted in hallmark serum cytokine increases, which correlated with fever and disease persistence. The novel finding of simultaneous development of IgG, IgM, and IgA responses in acute H7N9 infection points to the potential for live influenza viruses to elicit fast and potent protective antibodies to limit the infection.

  20. Sylvatic plague vaccine and management of prairie dogs

    Science.gov (United States)

    Rocke, Tonie E.

    2012-01-01

    Scientists at the USGS National Wildlife Health Center (NWHC), in collaboration with colleagues at the University of Wisconsin (UW), have developed a sylvatic plague vaccine that shows great promise in protecting prairie dogs against plague (Mencher and others, 2004; Rocke and others, 2010). Four species of prairie dogs reside in the United States and Canada, and all are highly susceptible to plague and regularly experience outbreaks with devastating losses. Along with habitat loss and poisoning, plague has contributed to a significant historical decline in prairie dog populations. By some estimates, prairie dogs now occupy only 1 to 2 percent of their former range (Proctor and others, 2006), with prairie dog colonies being now much smaller and fragmented than they were historically, making individual colonies more vulnerable to elimination by plague (Antolin and others, 2002). At least one species, the Utah prairie dog (Cynomys parvidens) is listed by the U.S. Fish and Wildlife Service (FWS) as "threatened." Controlling plague is a vital concern for ongoing management and conservation efforts for prairie dogs. Current efforts to halt the spread of plague in prairie dog colonies typically rely on dusting individual prairie dog burrows with pesticides to kill plague-infected fleas. Although flea-control insecticides, such as deltamethrin, are useful in stopping plague outbreaks in these prairie dog colonies, dusting of burrows is labor intensive and time consuming and may affect other insects and arthropods. As an alternative approach, NWHC and UW scientists developed a sylvatic plague vaccine (SPV) for prairie dogs that can be delivered via oral bait. Laboratory studies have shown that consumption of this vaccine-laden bait by different prairie dog species results in significant protection against plague infection that can last for at least 9 months (Rocke and others, 2010; Rocke, unpublished). Work has now shifted to optimizing baits and distribution methods for

  1. The starling (Sturnus vulgaris) as an experimental model for staphylococcal infection of the avian foot.

    Science.gov (United States)

    Cooper, J E; Needham, J R

    1981-07-01

    Inoculation of the footpad of the starling (Sturnus vulgaris) with a broth culture of Staphylococcus aureus resulted in a swelling of the foot and histological changes similar to those seen in bumblefoot in poultry and other species. In a number of cases S: aureus could be re-isolated. It is suggested that this could prove to be a useful model in the study of avian pododermatitis.

  2. Risk factors for highly pathogenic avian influenza (HPAI) H5N1 infection in backyard chicken farms, Thailand.

    Science.gov (United States)

    Paul, Mathilde; Wongnarkpet, Sirichai; Gasqui, Patrick; Poolkhet, Chaithep; Thongratsakul, Sukanya; Ducrot, Christian; Roger, François

    2011-06-01

    To reduce the risk of highly pathogenic avian influenza (HPAI) H5N1 infection in humans, the pathways by which HPAI is spread in poultry must be determined. Backyard poultry farmers are particularly vulnerable to the threat of HPAI, with both their health and livelihoods at risk. Identifying the risk factors for HPAI infection in backyard farms should allow control measures to be better targeted. To study the risk factors of HPAI H5N1 infection, we carried out a case-control study on backyard chicken farms in Thailand, analyzing 104 case farms and 382 control farms. Data on farming practices and environmental characteristics were analyzed using multivariate logistic regression models. We show that farms where owners bought live chickens from another backyard farm had a higher risk of HPAI H5N1 infection (OR 3.34, 95% CI 1.72-6.47), while those where owners used a disinfectant to clean poultry areas were exposed to lower risk (OR 0.48, 95% CI 0.26-0.87). Our results highlight the important role of the trade of poultry between farms in the transmission of HPAI H5N1, in addition to farming practices and environmental characteristics. Findings from this study may help to tailor prevention measures to the local circumstances of backyard farms in different regions of the world.

  3. Rodent and flea abundance fail to predict a plague epizootic in black-tailed prairie dogs.

    Science.gov (United States)

    Brinkerhoff, Robert Jory; Collinge, Sharon K; Ray, Chris; Gage, Ken L

    2010-01-01

    Small rodents are purported to be enzootic hosts of Yersinia pestis and may serve as sources of infection to prairie dogs or other epizootic hosts by direct or flea-mediated transmission. Recent research has shown that small rodent species composition and small rodent flea assemblages are influenced by the presence of prairie dogs, with higher relative abundance of both small rodents and fleas at prairie dog colony sites compared to grasslands without prairie dogs. However, it is unclear if increased rodent or flea abundance predisposes prairie dogs to infection with Y. pestis. We tracked rodent and flea occurrence for 3 years at a number of prairie dog colony sites in Boulder County, Colorado, before, during, and after a local plague epizootic to see if high rodent or flea abundance was associated with plague-affected colonies when compared to colonies that escaped infection. We found no difference in preepizootic rodent abundance or flea prevalence or abundance between plague-positive and plague-negative colonies. Further, we saw no significant before-plague/after-plague change in these metrics at either plague-positive or plague-negative sites. We did, however, find that small rodent species assemblages changed in the year following prairie dog die-offs at plague-affected colonies when compared to unaffected colonies. In light of previous research from this system that has shown that landscape features and proximity to recently plagued colonies are significant predictors of plague occurrence in prairie dogs, we suggest that landscape context is more important to local plague occurrence than are characteristics of rodent or flea species assemblages.

  4. Clinical severity of human infections with avian influenza A(H7N9) virus, China, 2013/14.

    Science.gov (United States)

    Feng, L; Wu, J T; Liu, X; Yang, P; Tsang, T K; Jiang, H; Wu, P; Yang, J; Fang, V J; Qin, Y; Lau, E H; Li, M; Zheng, J; Peng, Z; Xie, Y; Wang, Q; Li, Z; Leung, G M; Gao, G F; Yu, H; Cowling, B J

    2014-12-11

    Assessing the severity of emerging infections is challenging because of potential biases in case ascertainment. The first human case of infection with influenza A(H7N9) virus was identified in China in March 2013; since then, the virus has caused two epidemic waves in the country. There were 134 laboratory-confirmed cases detected in the first epidemic wave from January to September 2013. In the second epidemic wave of human infections with avian influenza A(H7N9) virus in China from October 2013 to October 2014, we estimated that the risk of death among hospitalised cases of infection with influenza A(H7N9) virus was 48% (95% credibility interval: 42-54%), slightly higher than the corresponding risk in the first wave. Age-specific risks of death among hospitalised cases were also significantly higher in the second wave. Using data on symptomatic cases identified through national sentinel influenza-like illness surveillance, we estimated that the risk of death among symptomatic cases of infection with influenza A(H7N9) virus was 0.10% (95% credibility interval: 0.029-3.6%), which was similar to previous estimates for the first epidemic wave of human infections with influenza A(H7N9) virus in 2013. An increase in the risk of death among hospitalised cases in the second wave could be real because of changes in the virus, because of seasonal changes in host susceptibility to severe infection, or because of variation in treatment practices between hospitals, while the increase could be artefactual because of changes in ascertainment of cases in different areas at different times.

  5. The Therapeutic Effect of Pamidronate on Lethal Avian Influenza A H7N9 Virus Infected Humanized Mice

    Science.gov (United States)

    Liu, Yinping; Xiang, Zheng; Liu, Ming; Chan, Kwok-Hung; Lau, Siu-Ying; Lam, Kwok-Tai; To, Kelvin Kai-Wang; Chan, Jasper Fuk-Woo; Li, Lanjuan; Chen, Honglin; Lau, Yu-Lung; Yuen, Kwok-Yung; Tu, Wenwei

    2015-01-01

    A novel avian influenza virus H7N9 infection occurred among human populations since 2013. Although the lack of sustained human-to-human transmission limited the epidemics caused by H7N9, the late presentation of most patients and the emergence of neuraminidase-resistant strains made the development of novel antiviral strategy against H7N9 in urgent demands. In this study, we evaluated the potential of pamidronate, a pharmacological phosphoantigen that can specifically boost human Vδ2-T-cell, on treating H7N9 virus-infected humanized mice. Our results showed that intraperitoneal injection of pamidronate could potently decrease the morbidity and mortality of H7N9-infected mice through controlling both viral replication and inflammation in affected lungs. More importantly, pamidronate treatment starting from 3 days after infection could still significantly ameliorate the severity of diseases in infected mice and improve their survival chance, whereas orally oseltamivir treatment starting at the same time showed no therapeutic effects. As for the mechanisms underlying pamidronate-based therapy, our in vitro data demonstrated that its antiviral effects were partly mediated by IFN-γ secreted from human Vδ2-T cells. Meanwhile, human Vδ2-T cells could directly kill virus-infected host cells in a perforin-, granzyme B- and CD137-dependent manner. As pamidronate has been used for osteoporosis treatment for more than 20 years, pamidronate-based therapy represents for a safe and readily available option for clinical trials to treat H7N9 infection. PMID:26285203

  6. The Therapeutic Effect of Pamidronate on Lethal Avian Influenza A H7N9 Virus Infected Humanized Mice.

    Directory of Open Access Journals (Sweden)

    Jian Zheng

    Full Text Available A novel avian influenza virus H7N9 infection occurred among human populations since 2013. Although the lack of sustained human-to-human transmission limited the epidemics caused by H7N9, the late presentation of most patients and the emergence of neuraminidase-resistant strains made the development of novel antiviral strategy against H7N9 in urgent demands. In this study, we evaluated the potential of pamidronate, a pharmacological phosphoantigen that can specifically boost human Vδ2-T-cell, on treating H7N9 virus-infected humanized mice. Our results showed that intraperitoneal injection of pamidronate could potently decrease the morbidity and mortality of H7N9-infected mice through controlling both viral replication and inflammation in affected lungs. More importantly, pamidronate treatment starting from 3 days after infection could still significantly ameliorate the severity of diseases in infected mice and improve their survival chance, whereas orally oseltamivir treatment starting at the same time showed no therapeutic effects. As for the mechanisms underlying pamidronate-based therapy, our in vitro data demonstrated that its antiviral effects were partly mediated by IFN-γ secreted from human Vδ2-T cells. Meanwhile, human Vδ2-T cells could directly kill virus-infected host cells in a perforin-, granzyme B- and CD137-dependent manner. As pamidronate has been used for osteoporosis treatment for more than 20 years, pamidronate-based therapy represents for a safe and readily available option for clinical trials to treat H7N9 infection.

  7. Plague outbreak in Libya, 2009, unrelated to plague in Algeria.

    Science.gov (United States)

    Cabanel, Nicolas; Leclercq, Alexandre; Chenal-Francisque, Viviane; Annajar, Badereddin; Rajerison, Minoarisoa; Bekkhoucha, Souad; Bertherat, Eric; Carniel, Elisabeth

    2013-02-01

    After 25 years of no cases of plague, this disease recurred near Tobruk, Libya, in 2009. An epidemiologic investigation identified 5 confirmed cases. We determined ribotypes, Not1 restriction profiles, and IS100 and IS1541 hybridization patterns of strains isolated during this outbreak. We also analyzed strains isolated during the 2003 plague epidemic in Algeria to determine whether there were epidemiologic links between the 2 events. Our results demonstrate unambiguously that neighboring but independent plague foci coexist in Algeria and Libya. They also indicate that these outbreaks were most likely caused by reactivation of organisms in local or regional foci believed to be dormant (Libya) or extinct (Algeria) for decades, rather than by recent importation of Yersinia pestis from distant foci. Environmental factors favorable for plague reemergence might exist in this area and lead to reactivation of organisms in other ancient foci.

  8. Plague Outbreak in Libya, 2009, Unrelated to Plague in Algeria

    Science.gov (United States)

    Cabanel, Nicolas; Leclercq, Alexandre; Chenal-Francisque, Viviane; Annajar, Badereddin; Rajerison, Minoarisoa; Bekkhoucha, Souad; Bertherat, Eric

    2013-01-01

    After 25 years of no cases of plague, this disease recurred near Tobruk, Libya, in 2009. An epidemiologic investigation identified 5 confirmed cases. We determined ribotypes, Not1 restriction profiles, and IS100 and IS1541 hybridization patterns of strains isolated during this outbreak. We also analyzed strains isolated during the 2003 plague epidemic in Algeria to determine whether there were epidemiologic links between the 2 events. Our results demonstrate unambiguously that neighboring but independent plague foci coexist in Algeria and Libya. They also indicate that these outbreaks were most likely caused by reactivation of organisms in local or regional foci believed to be dormant (Libya) or extinct (Algeria) for decades, rather than by recent importation of Yersinia pestis from distant foci. Environmental factors favorable for plague reemergence might exist in this area and lead to reactivation of organisms in other ancient foci. PMID:23347743

  9. The Formula of Plague Narratives

    DEFF Research Database (Denmark)

    Christensen, Jørgen Riber

    2015-01-01

    it is possible to establish a stable formula for plague narratives despite the spread over centuries and in different text types, and to explain this formula and possible variations of it. The initial and tentative hypothesis is that a formulaic narrative structure exists for accounts, both documentary...... and fictional, of epidemics. The samples include: Exodus, History of the Peloponnesian War, Samuel Pepys’ Diary, A Journal of the Plague Year, The Last Man, The Plague in Bergamo, Discipline and Punish: The Birth of the Prison, Doomsday, The Dead Zone, World War Z. An Oral History of the Zombie War, Pandemic...

  10. A Case Report of Avian Polyomavirus Infection in a Blue Fronted Parrot (Amazona aestiva Associated with Anemia

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    Natalia Azevedo Philadelpho

    2015-01-01

    Full Text Available An adult Blue Fronted Amazon parrot (A. aestiva presenting with emesis, apathy, undigested seed in feces, and severe anemia was treated for approximately 2 months. Upon radiographic examination, an enlarged kidney was the only alteration. PCR for avian Bornavirus, Circovirus, and Polyomavirus was performed for the feces and blood. The results were positive for APV in both samples and negative for the other viruses. After 6 months, the feces from the same animal were negative for APV. Because the animal was positive for APV in both the feces and the blood, it is likely that these clinical symptoms were due to Polyomavirus infection. Severe anemia is an unusual clinical sign of Polyomavirus, and this study aims to identify novel differential diagnostic criteria for the disease.

  11. Plague and the Human Flea, Tanzania

    DEFF Research Database (Denmark)

    Laudisoit, Anne; Leirs, Herwig; Makundi, Rhodes H

    2007-01-01

    Domestic fleas were collected in 12 villages in the western Usambara Mountains in Tanzania. Of these, 7 are considered villages with high plague frequency, where human plague was recorded during at least 6 of the 17 plague seasons between 1986 and 2004. In the remaining 5 villages with low plague...

  12. Potential infections of H5N1 and H9N2 avian influenza do exist in Guangdong populations of China

    Institute of Scientific and Technical Information of China (English)

    LU Ci-yong; LU Jia-hai; CHEN Wei-qing; JIANG Li-fang; TAN Bing-yan; LING Wen-hua; ZHENG Bo-jian; SUI Hong-yan

    2008-01-01

    Background Southeast China is one of the sites of influenza origin. During 2003-2004, nine avian influenza outbreaks took place in Guangdong Province. But no human case was reported. To examine the status of potential human infection by human influenza (H1N1, H3N2) and avian influenza (H5N1, H7N7, H9N2) in the avian influenza epidemic area of Guangdong Province, China, we conducted a seroepidemiologic survey in the people of this area from April to June of 2004.Methods Three out of 9 H5N1 avian influenza affected poultry areas in Guangdong were randomly selected, and the population living within 3 kilometers of the affected poultries were chosen as the survey subjects. One thousand two hundred and fourteen people were selected from 3 villages at random. Human and avian influenza antibody tilers were determined by hemagglutination-inhibition (HI) test and microneutralization test (MNT).Results The positive rate of antibody to H5N1 was 3.03% in the occupational exposure group and 2.34% in general citizens group; that of H9N2 was 9.52% in the occupational exposure group and 3.76% in the general citizens group. Moreover one case in the occupational exposure group was positive for H7N7. One year later, all previously positive cases had become negative except for one H5N1 -positive case.Conclusion The observations imply that H5N1 and H9N2 avian influenza silent infections exist in Guangdon gpopulations.

  13. Deterioration of eggshell quality in laying hens experimentally infected with H9N2 avian influenza virus.

    Science.gov (United States)

    Qi, Xuefeng; Tan, Dan; Wu, Chengqi; Tang, Chao; Li, Tao; Han, Xueying; Wang, Jing; Liu, Caihong; Li, Ruiqiao; Wang, Jingyu

    2016-02-25

    This study aimed to determine the mechanism by which H9N2 avian influenza virus (AIV) affects eggshell quality. Thirty-week-old specific pathogen free egg-laying hens were inoculated with the chicken-origin H9N2 AIV strain (A/Chicken/shaanxi/01/2011) or with inoculating media without virus by combined intraocular and intranasal routes. The time course for the appearance of viral antigen and tissue lesions in the oviduct was coincident with the adverse changes in egg production in the infected hens. The viral loads of AIV have a close correlation with the changes in the uterus CaBP-D28k mRNA expression as well as the Ca concentrations in the eggshells in the infected hens from 1 to 7 days post inoculation (dpi). Ultrastructural examination of eggshells showed significantly decreased shell thickness in the infected hens from 1 to 5 dpi (P hens from 1 to 5 dpi as compared with the control hens. In conclusion, this study confirmed that H9N2 AIV strain (A/Chicken/shaanxi/01/2011) infection is associated with severe lesions of the uterus and abnormal expression of CaBP-D28k mRNA in the uteri of the infected hens. The change of CaBP-D28k mRNA expression may contribute to the deterioration of the eggshell quality of the laying hens infected with AIV. It is noteworthy that the pathogenicity of H9N2 AIV strains may vary depending on the virus strain and host preference.

  14. Avian cardiology.

    Science.gov (United States)

    Strunk, Anneliese; Wilson, G Heather

    2003-01-01

    The field of avian cardiology is continually expanding. Although a great deal of the current knowledge base has been derived from poultry data, research and clinical reports involving companion avian species have been published. This article will present avian cardiovascular anatomy and physiology, history and physical examination considerations in the avian cardiac disease patient, specific diagnostic tools, cardiovascular disease processes, and current therapeutic modalities.

  15. Estimating the Distribution of the Incubation Periods of Human Avian Influenza A(H7N9) Virus Infections

    Science.gov (United States)

    Virlogeux, Victor; Li, Ming; Tsang, Tim K.; Feng, Luzhao; Fang, Vicky J.; Jiang, Hui; Wu, Peng; Zheng, Jiandong; Lau, Eric H. Y.; Cao, Yu; Qin, Ying; Liao, Qiaohong; Yu, Hongjie; Cowling, Benjamin J.

    2015-01-01

    A novel avian influenza virus, influenza A(H7N9), emerged in China in early 2013 and caused severe disease in humans, with infections occurring most frequently after recent exposure to live poultry. The distribution of A(H7N9) incubation periods is of interest to epidemiologists and public health officials, but estimation of the distribution is complicated by interval censoring of exposures. Imputation of the midpoint of intervals was used in some early studies, resulting in estimated mean incubation times of approximately 5 days. In this study, we estimated the incubation period distribution of human influenza A(H7N9) infections using exposure data available for 229 patients with laboratory-confirmed A(H7N9) infection from mainland China. A nonparametric model (Turnbull) and several parametric models accounting for the interval censoring in some exposures were fitted to the data. For the best-fitting parametric model (Weibull), the mean incubation period was 3.4 days (95% confidence interval: 3.0, 3.7) and the variance was 2.9 days; results were very similar for the nonparametric Turnbull estimate. Under the Weibull model, the 95th percentile of the incubation period distribution was 6.5 days (95% confidence interval: 5.9, 7.1). The midpoint approximation for interval-censored exposures led to overestimation of the mean incubation period. Public health observation of potentially exposed persons for 7 days after exposure would be appropriate. PMID:26409239

  16. Predicting the risk of avian influenza A H7N9 infection in live-poultry markets across Asia.

    Science.gov (United States)

    Gilbert, Marius; Golding, Nick; Zhou, Hang; Wint, G R William; Robinson, Timothy P; Tatem, Andrew J; Lai, Shengjie; Zhou, Sheng; Jiang, Hui; Guo, Danhuai; Huang, Zhi; Messina, Jane P; Xiao, Xiangming; Linard, Catherine; Van Boeckel, Thomas P; Martin, Vincent; Bhatt, Samir; Gething, Peter W; Farrar, Jeremy J; Hay, Simon I; Yu, Hongjie

    2014-06-17

    Two epidemic waves of an avian influenza A (H7N9) virus have so far affected China. Most human cases have been attributable to poultry exposure at live-poultry markets, where most positive isolates were sampled. The potential geographic extent of potential re-emerging epidemics is unknown, as are the factors associated with it. Using newly assembled data sets of the locations of 8,943 live-poultry markets in China and maps of environmental correlates, we develop a statistical model that accurately predicts the risk of H7N9 market infection across Asia. Local density of live-poultry markets is the most important predictor of H7N9 infection risk in markets, underscoring their key role in the spatial epidemiology of H7N9, alongside other poultry, land cover and anthropogenic predictor variables. Identification of areas in Asia with high suitability for H7N9 infection enhances our capacity to target biosurveillance and control, helping to restrict the spread of this important disease.

  17. Risk Distribution of Human Infections with Avian Influenza H7N9 and H5N1 virus in China.

    Science.gov (United States)

    Li, Xin-Lou; Yang, Yang; Sun, Ye; Chen, Wan-Jun; Sun, Ruo-Xi; Liu, Kun; Ma, Mai-Juan; Liang, Song; Yao, Hong-Wu; Gray, Gregory C; Fang, Li-Qun; Cao, Wu-Chun

    2015-12-22

    It has been documented that the epidemiological characteristics of human infections with H7N9 differ significantly between H5N1. However, potential factors that may explain the different spatial distributions remain unexplored. We use boosted regression tree (BRT) models to explore the association of agro-ecological, environmental and meteorological variables with the occurrence of human cases of H7N9 and H5N1, and map the probabilities of occurrence of human cases. Live poultry markets, density of human, coverage of built-up land, relative humidity and precipitation were significant predictors for both. In addition, density of poultry, coverage of shrub and temperature played important roles for human H7N9 infection, whereas human H5N1 infection was associated with coverage of forest and water body. Based on the risks and distribution of ecological characteristics which may facilitate the circulation of the two viruses, we found Yangtze River Delta and Pearl River Delta, along with a few spots on the southeast coastline, to be the high risk areas for H7N9 and H5N1. Additional, H5N1 risk spots were identified in eastern Sichuan and southern Yunnan Provinces. Surveillance of the two viruses needs to be enhanced in these high risk areas to reduce the risk of future epidemics of avian influenza in China.

  18. Global and Quantitative Proteomic Analysis of Dogs Infected by Avian-like H3N2 Canine Influenza Virus

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    Shuo eSu

    2015-04-01

    Full Text Available Canine influenza virus A (H3N2 is a newly emerged etiological agent for respiratory infections in dogs. The mechanism of interspecies transmission from avian to canine species and the development of diseases in this new host remain to be explored. To investigate this, we conducted a differential proteomics study in two-month old beagles inoculated intranasally with 106 TCID50 of A/canine/Guangdong/01/2006 (H3N2 virus. Lung sections excised at 12 hours post-inoculation (hpi, 4 days, and 7 days post-inoculation (dpi were processed for global and quantitative analysis of differentially expressed proteins. A total of 17,796 proteins were identified at different time points. About 1.6% was differentially expressed between normal and infected samples. Of these, 23, 27 and 136 polypeptides were up-regulated, and 14, 18 and 123 polypeptides were down-regulated, at 12 hpi, 4 dpi, and 7 dpi, respectively. Vann diagram analysis indicated that 17 proteins were up-regulated and one was down-regulated at all three time points. Selected proteins were validated by real-time PCR and by Western blot. Our results show that apoptosis and cytoskeleton-associated proteins expression was suppressed, whereas interferon-induced proteins plus other innate immunity proteins were induced after the infection. Understanding of the interactions between virus and the host will provide insights into the basis of interspecies transmission, adaptation, and virus pathogenicity.

  19. Conserved host response to highly pathogenic avian influenza virus infection in human cell culture, mouse and macaque model systems

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    McDermott Jason E

    2011-11-01

    Full Text Available Abstract Background Understanding host response to influenza virus infection will facilitate development of better diagnoses and therapeutic interventions. Several different experimental models have been used as a proxy for human infection, including cell cultures derived from human cells, mice, and non-human primates. Each of these systems has been studied extensively in isolation, but little effort has been directed toward systematically characterizing the conservation of host response on a global level beyond known immune signaling cascades. Results In the present study, we employed a multivariate modeling approach to characterize and compare the transcriptional regulatory networks between these three model systems after infection with a highly pathogenic avian influenza virus of the H5N1 subtype. Using this approach we identified functions and pathways that display similar behavior and/or regulation including the well-studied impact on the interferon response and the inflammasome. Our results also suggest a primary response role for airway epithelial cells in initiating hypercytokinemia, which is thought to contribute to the pathogenesis of H5N1 viruses. We further demonstrate that we can use a transcriptional regulatory model from the human cell culture data to make highly accurate predictions about the behavior of important components of the innate immune system in tissues from whole organisms. Conclusions This is the first demonstration of a global regulatory network modeling conserved host response between in vitro and in vivo models.

  20. Avian influenza

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    Tjandra Y. Aditama

    2006-06-01

    Full Text Available Avian influenza, or “bird flu”, is a contagious disease of animals which crossed the species barrier to infect humans and gave a quite impact on public health in the world since 2004, especially due to the threat of pandemic situation. Until 1st March 2006, laboratory-confirmed human cases have been reported in seven countries: Cambodia, Indonesia, Thailand, Viet Nam, China, Iraq and Turkey with a total of 174 cases and 94 dead (54.02%. Indonesia has 27 cases, 20 were dead (74.07%. AI cases in Indonesia are more in male (62.5% and all have a symptom of fever. An influenza pandemic is a rare but recurrent event. An influenza pandemic happens when a new subtype emerges that has not previously circulated in humans. For this reason, avian H5N1 is a strain with pandemic potential, since it might ultimately adapt into a strain that is contagious among humans. Impact of the pandemic could include high rates of illness and worker absenteeism are expected, and these will contribute to social and economic disruption. Historically, the number of deaths during a pandemic has varied greatly. Death rates are largely determined by four factors: the number of people who become infected, the virulence of the virus, the underlying characteristics and vulnerability of affected populations, and the effectiveness of preventive measures. Accurate predictions of mortality cannot be made before the pandemic virus emerges and begins to spread. (Med J Indones 2006; 15:125-8Keywords: Avian Influenza, Pandemic

  1. Characterization of two distinct neuraminidases from avian-origin human-infecting H7N9 influenza viruses.

    Science.gov (United States)

    Wu, Yan; Bi, Yuhai; Vavricka, Christopher J; Sun, Xiaoman; Zhang, Yanfang; Gao, Feng; Zhao, Min; Xiao, Haixia; Qin, Chengfeng; He, Jianhua; Liu, Wenjun; Yan, Jinghua; Qi, Jianxun; Gao, George F

    2013-12-01

    An epidemic of an avian-origin H7N9 influenza virus has recently emerged in China, infecting 134 patients of which 45 have died. This is the first time that an influenza virus harboring an N9 serotype neuraminidase (NA) has been known to infect humans. H7N9 viruses are divergent and at least two distinct NAs and hemagglutinins (HAs) have been found, respectively, from clinical isolates. The prototypes of these viruses are A/Anhui/1/2013 and A/Shanghai/1/2013. NAs from these two viruses are distinct as the A/Shanghai/1/2013 NA has an R294K substitution that can confer NA inhibitor oseltamivir resistance. Oseltamivir is by far the most commonly used anti-influenza drug due to its potency and high bioavailability. In this study, we show that an R294K substitution results in multidrug resistance with extreme oseltamivir resistance (over 100 000-fold) using protein- and virus-based assays. To determine the molecular basis for the inhibitor resistance, we solved high-resolution crystal structures of NAs from A/Anhui/1/2013 N9 (R294-containing) and A/Shanghai/1/2013 N9 (K294-containing). R294K substitution results in an unfavorable E276 conformation for oseltamivir binding, and consequently loss of inhibitor carboxylate interactions, which compromises the binding of all classical NA ligands/inhibitors. Moreover, we found that R294K substitution results in reduced NA catalytic efficiency along with lower viral fitness. This helps to explain why K294 has predominantly been found in clinical cases of H7N9 infection under the selective pressure of oseltamivir treatment and not in the dominant human-infecting viruses. This implies that oseltamivir can still be efficiently used in the treatment of H7N9 infections.

  2. Microwave or autoclave treatments destroy the infectivity of infectious bronchitis virus and avian pneumovirus but allow detection by reverse transcriptase-polymerase chain reaction.

    Science.gov (United States)

    Elhafi, G; Naylor, C J; Savage, C E; Jones, R C

    2004-06-01

    A method is described for enabling safe transit of denatured virus samples for polymerase chain reaction (PCR) identification without the risk of unwanted viable viruses. Cotton swabs dipped in avian infectious bronchitis virus (IBV) or avian pneumovirus (APV) were allowed to dry. Newcastle disease virus and avian influenza viruses were used as controls. Autoclaving and microwave treatment for as little as 20 sec destroyed the infectivity of all four viruses. However, both IBV and APV could be detected by reverse transcriptase (RT)-PCR after autoclaving and as long as 5 min microwave treatment (Newcastle disease virus and avian influenza viruses were not tested). Double microwave treatment of IBV and APV with an interval of 2 to 7 days between was tested. After the second treatment, RT-PCR products were readily detected in all samples. Swabs from the tracheas and cloacas of chicks infected with IBV shown to contain infectious virus were microwaved. Swabs from both sources were positive by RT-PCR. Microwave treatment appears to be a satisfactory method of inactivating virus while preserving nucleic acid for PCR identification.

  3. Human bubonic plague transmitted by a domestic cat scratch.

    Science.gov (United States)

    Weniger, B G; Warren, A J; Forseth, V; Shipps, G W; Creelman, T; Gorton, J; Barnes, A M

    1984-02-17

    Bubonic plague was transmitted to a 10-year-old girl in Oregon by a scratch wound inflicted by a domestic cat. The cat probably was infected by contact with infected wild rodents or their fleas. Yersinia pestis was identified in Diamanus montanus fleas collected from an abandoned burrow near the patient's home. Domestic cats may infect humans with Y pestis by inoculation from a scratch.

  4. Increased avian diversity is associated with lower incidence of human West Nile infection: observation of the dilution effect.

    Directory of Open Access Journals (Sweden)

    John P Swaddle

    Full Text Available Recent infectious disease models illustrate a suite of mechanisms that can result in lower incidence of disease in areas of higher disease host diversity--the 'dilution effect'. These models are particularly applicable to human zoonoses, which are infectious diseases of wildlife that spill over into human populations. As many recent emerging infectious diseases are zoonoses, the mechanisms that underlie the 'dilution effect' are potentially widely applicable and could contribute greatly to our understanding of a suite of diseases. The dilution effect has largely been observed in the context of Lyme disease and the predictions of the underlying models have rarely been examined for other infectious diseases on a broad geographic scale. Here, we explored whether the dilution effect can be observed in the relationship between the incidence of human West Nile virus (WNV infection and bird (host diversity in the eastern US. We constructed a novel geospatial contrasts analysis that compares the small differences in avian diversity of neighboring US counties (where one county reported human cases of WNV and the other reported no cases with associated between-county differences in human disease. We also controlled for confounding factors of climate, regional variation in mosquito vector type, urbanization, and human socioeconomic factors that are all likely to affect human disease incidence. We found there is lower incidence of human WNV in eastern US counties that have greater avian (viral host diversity. This pattern exists when examining diversity-disease relationships both before WNV reached the US (in 1998 and once the epidemic was underway (in 2002. The robust disease-diversity relationships confirm that the dilution effect can be observed in another emerging infectious disease and illustrate an important ecosystem service provided by biodiversity, further supporting the growing view that protecting biodiversity should be considered in public

  5. Human infection with an avian influenza A (H9N2) virus in the middle region of China.

    Science.gov (United States)

    Huang, Yiwei; Li, Xiaodan; Zhang, Hong; Chen, Bozhong; Jiang, Yonglin; Yang, Lei; Zhu, Wenfei; Hu, Shixiong; Zhou, Siyu; Tang, Yunli; Xiang, Xingyu; Li, Fangcai; Li, Wenchao; Gao, Lidong

    2015-10-01

    During the epidemic period of the novel H7N9 viruses, an influenza A (H9N2) virus was isolated from a 7-year-old boy with influenza-like illness in Yongzhou city of Hunan province in November 2013. To identify the possible source of infection, environmental specimens collected from local live poultry markets epidemiologically linked to the human case in Yongzhou city were tested for influenza type A and its subtypes H5, H7, and H9 using real-time RT-PCR methods as well as virus isolation, and four other H9N2 viruses were isolated. The real-time RT-PCR results showed that the environment was highly contaminated with avian influenza H9 subtype viruses (18.0%). Sequencing analyses revealed that the virus isolated from the patient, which was highly similar (98.5-99.8%) to one of isolates from environment in complete genome sequences, was of avian origin. Based on phylogenetic and antigenic analyses, it belonged to genotype S and Y280 lineage. In addition, the virus exhibited high homology (95.7-99.5%) of all six internal gene lineages with the novel H7N9 and H10N8 viruses which caused epidemic and endemic in China. Meanwhile, it carried several mammalian adapted molecular residues including Q226L in HA protein, L13P in PB1 protein, K356R, S409N in PA protein, V15I in M1 protein, I28V, L55F in M2 protein, and E227K in NS protein. These findings reinforce the significance of continuous surveillance of H9N2 influenza viruses.

  6. Serologic cross-reactivity among humans and birds infected with highly pathogenic avian influenza A subtype H5N1 viruses in China.

    Science.gov (United States)

    Li, Zheng; Ma, Chi; Liu, Zhonghua; He, Wei

    2011-03-30

    To study immunogenicity and serologic cross-reactivity of hemagglutinins (HAs) among humans and birds infected with highly pathogenic avian influenza (HPAI) H5N1, four representative H5N1 HA genes from humans and birds infected with distinct genetic clusters of H5N1 viruses in China were cloned, and several H5N1 infected human serum and H5N1 positive bird serum samples were used. Recombinant HA proteins were generated for ELISA assays and pseudotype viruses containing HAs were produced for neutralization assays and hemagglutination inhibition (HI) tests. We found significant differences among clades compared to species in binding, neutralization and HI activity of H5N1 strains isolated from birds. While significant differences were observed among species in H5N1 isolated from humans, investigation of H5N1 infected human and avian sera provided evidence that the pressure from nAb may be a driving force for positive selection. Therefore, improved anti-viral nAb therapies could block avian influenza transmission in humans.

  7. The threatened plague.

    Science.gov (United States)

    Epstein, P

    1997-01-01

    This article discusses changes in disease patterns affecting human health that may be related to environmental and social changes in the world. The World Health Report reveals that 30 new diseases emerged in the past 20 years. Old diseases are becoming resistant to new drugs. Infectious diseases that were in decline are spreading: diphtheria, whooping cough, and measles. Illnesses such as malaria, fevers, cholera, and rodent-borne viruses are becoming more frequent. Diseases that are transmitted by animals or water are related to environmental and social changes. Degraded environments are susceptible to the appearance of opportunistic species, such as weeds, rodents, insects, and microorganisms. Stable environments support the welfare of large predators and control opportunistic species. Owls, coyotes, and snakes eat rodents that carry Lyme disease ticks and a variety of viruses, plague, and bacteria. Reptiles, birds, spiders, ladybugs, bats, and fish consume larvae and mosquitoes that cause malaria and fevers. Habitat loss and fragmentation, monocultures, excessive use of toxic chemicals, climate change, and weather instability are widespread global changes that reduce the predator population. Small wilderness habitats favor pests. Monocultures reduce genetic diversity and increase vulnerability. Excessive use of pesticides harms birds and helpful insects. A sign of a failing ecosystem is the population explosion of pests and disequilibrium. The Environmental Distress Syndrome is characterized as: 1) emerging infectious diseases, 2) loss of biodiversity, 3) increased generalist species and decreased specialist species, 4) declines in specific specialists, such as pollinators responsible for preservation of flowering plants, and 5) increased coastal algal blooms. The impacts of disease mean considerable costs to humans, agriculture, and livestock. Loss of resources is also costly.

  8. Field Investigation on the Prevalence of Avian Influenza Virus Infection in Some Localities in Saudi Arabia

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    Abdullah N. Alkhalaf

    2010-07-01

    Full Text Available The objective of this study was to find out prevalence and types of avian influenza virus (AIV among broilers, native chickens, ducks and pigeons in Saudi Arabia. Field investigation was carried out in four localities including Al-Qassim, Hail, Al-Jouf and Northern Border regions. Serum sample, tracheal and cloacal swabs were collected from broilers (n=1561, layers (n=988, ducks (n=329 and pigeons (n=450 from these localities and tested for three different avian influenza viruses (H9, H5 and H3 using Enzyme linked immunosorbent (ELISA test, hamagglutination inhibition (HI test and polymerase chain reaction (PCR. All tested samples were negative for H5 and H3 viruses. In contrast, all positive results were found to be for H9 AI virus using PCR, ELISA and HI test. Chicken sera tested by ELISA for AIV revealed the highest positive samples in Northern Border regions (45.71%, followed by Al-Jouf (29.65%, Al-Qassim (23.98% and Hial (20.94% with non-significant difference (χ2=5.983; P=0.112. HI test carried out on duck sera revealed 35.90% prevalence of antibodies against AIV. PCR amplification resulted in 34.28 and 21.36% positive samples in ducks and chickens, respectively. The highest (45.71% PCR positive chicken samples were from Northern Border regions, followed by Al-Jouf (24.13%, Al-Qassim (19.30% and Hail (16.69% with significant difference (χ2=7.620; P=0.055. All tested pigeons samples were negative for the three virus serotypes included in the study.

  9. Response of white leghorn chickens to infection with avian leukosis virus subgroup J and infectious bursal disease virus.

    Science.gov (United States)

    Williams, Susan M; Sellers, Holly S

    2012-03-01

    The effects of viral-induced immunosuppression on the infectious status (viremia and antibody) and shedding of avian leukosis virus (ALV) were studied. Experimental white leghorn chickens were inoculated with ALV subgroup J (ALV-J) and infectious bursal disease virus (IBDV) at day of hatch with the ALV-J ADOL prototype strain Hcl, the Lukert strain of IBDV, or both. Appropriate groups were exposed a second time with the Lukert strain at 2 wk of age. Serum samples were collected at 2 and 4 wk of age for IBDV antibody detection. Samples for ALV-J viremia, antibody detection, and cloacal shedding were collected at 4, 10, 18, and 30 wk of age. The experiment was terminated at 30 wk of age, and birds were necropsied and examined grossly for tumor development. Neoplasias detected included hemangiomas, bile duct carcinoma, and anaplastic sarcoma of the nerve. Control birds and IBDV-infected birds were negative for ALV-J-induced viremia, antibodies, and cloacal shedding throughout experiment. By 10 wk, ALV-J-infected groups began to develop antibodies to ALV-J. However, at 18 wk the incidence of virus isolation increased in both groups, with a simultaneous decrease in antibody levels. At 30 wk, 97% of birds in the ALV-J group were virus positive and 41% were antibody positive. In the ALV-J/IDBV group, 96% of the birds were virus positive at 30 wk, and 27% had antibodies to ALV-J. In this study, infection with a mild classic strain of IBDV did not influence ALV-J infection or antibody production.

  10. Detection of Avian bornavirus in multiple tissues of infected psittacine birds using real-time reverse transcription polymerase chain reaction.

    Science.gov (United States)

    Delnatte, Pauline; Mak, Matthew; Ojkic, Davor; Raghav, Raj; DeLay, Josepha; Smith, Dale A

    2014-03-01

    Avian bornavirus (ABV), the cause of proventricular dilation disease in psittacine birds, has been detected in multiple tissues of infected birds using immunohistochemical staining (IHC) and reverse transcription polymerase chain reaction (RT-PCR). In the current study, real-time RT-PCR, using primers targeting the ABV matrix gene, was used to detect ABV in 146 tissues from 7 ABV-infected psittacine birds. Eighty-six percent of the samples tested positive, with crossing point values ranging from 13.82 to 37.82 and a mean of 22.3. These results were compared to the findings of a previous study using gel-based RT-PCR and IHC on the same samples. The agreement between the 2 RT-PCR techniques was 91%; when tests disagreed it was because samples were negative using gel-based RT-PCR but positive on real-time RT-PCR. Agreement with IHC was 77%; 16 out of 74 samples were negative using IHC but positive on real-time RT-PCR. The results suggest that real-time RT-PCR is a more sensitive technique than gel-based RT-PCR and IHC to detect ABV in tissues. The tissues that were ranked most frequently as having a high amount of viral RNA were proventriculus, kidney, colon, cerebrum, and cerebellum. Skeletal muscle, on the other hand, was found to have a consistently low amount of viral RNA.

  11. Comprehensive analysis of antibody recognition in convalescent humans from highly pathogenic avian influenza H5N1 infection.

    Science.gov (United States)

    Zuo, Teng; Sun, Jianfeng; Wang, Guiqin; Jiang, Liwei; Zuo, Yanan; Li, Danyang; Shi, Xuanling; Liu, Xi; Fan, Shilong; Ren, Huanhuan; Hu, Hongxing; Sun, Lina; Zhou, Boping; Liang, Mifang; Zhou, Paul; Wang, Xinquan; Zhang, Linqi

    2015-12-04

    Understanding the mechanism of protective antibody recognition against highly pathogenic avian influenza A virus H5N1 in humans is critical for the development of effective therapies and vaccines. Here we report the crystal structure of three H5-specific human monoclonal antibodies bound to the globular head of hemagglutinin (HA) with distinct epitope specificities, neutralization potencies and breadth. A structural and functional analysis of these epitopes combined with those reported elsewhere identifies four major vulnerable sites on the globular head of H5N1 HA. Chimeric and vulnerable site-specific mutant pseudoviruses are generated to delineate broad neutralization specificities of convalescent sera from two individuals who recovered from the infection with H5N1 virus. Our results show that the four vulnerable sites on the globular head rather than the stem region are the major neutralizing targets, suggesting that during natural H5N1 infection neutralizing antibodies against the globular head work in concert to provide protective antibody-mediated immunity.

  12. The dynamics of avian influenza in western Arctic snow geese: implications for annual and migratory infection patterns

    Science.gov (United States)

    Samuel, Michael D.; Hall, Jeffrey S.; Brown, Justin D.; Goldberg, Diana R.; Ip, Hon S.; Baranyuk, Vasily V.

    2015-01-01

    Wild water birds are the natural reservoir for low-pathogenic avian influenza viruses (AIV). However, our ability to investigate the epizootiology of AIV in these migratory populations is challenging, and despite intensive worldwide surveillance, remains poorly understood. We conducted a cross-sectional, retrospective analysis in Pacific Flyway lesser snow geese Chen caerulescens to investigate AIV serology and infection patterns. We collected nearly 3,000 sera samples from snow geese at 2 breeding colonies in Russia and Canada during 1993-1996 and swab samples from > 4,000 birds at wintering and migration areas in the United States during 2006-2011. We found seroprevalence and annual seroconversion varied considerably among years. Seroconversion and infection rates also differed between snow goose breeding colonies and wintering areas, suggesting that AIV exposure in this gregarious waterfowl species is likely occurring during several phases (migration, wintering and potentially breeding areas) of the annual cycle. We estimated AIV antibody persistence was longer (14 months) in female geese compared to males (6 months). This relatively long period of AIV antibody persistence suggests that subtype-specific serology may be an effective tool for detection of exposure to subtypes associated with highly-pathogenic AIV. Our study provides further evidence of high seroprevalence in Arctic goose populations, and estimates of annual AIV seroconversion and antibody persistence for North American waterfowl. We suggest future AIV studies include serology to help elucidate the epizootiological dynamics of AIV in wild bird populations.

  13. Deep sequencing-based transcriptome analysis of chicken spleen in response to avian pathogenic Escherichia coli (APEC infection.

    Directory of Open Access Journals (Sweden)

    Qinghua Nie

    Full Text Available Avian pathogenic Escherichia coli (APEC leads to economic losses in poultry production and is also a threat to human health. The goal of this study was to characterize the chicken spleen transcriptome and to identify candidate genes for response and resistance to APEC infection using Solexa sequencing. We obtained 14422935, 14104324, and 14954692 Solexa read pairs for non-challenged (NC, challenged-mild pathology (MD, and challenged-severe pathology (SV, respectively. A total of 148197 contigs and 98461 unigenes were assembled, of which 134949 contigs and 91890 unigenes match the chicken genome. In total, 12272 annotated unigenes take part in biological processes (11664, cellular components (11927, and molecular functions (11963. Summing three specific contrasts, 13650 significantly differentially expressed unigenes were found in NC Vs. MD (6844, NC Vs. SV (7764, and MD Vs. SV (2320. Some unigenes (e.g. CD148, CD45 and LCK were involved in crucial pathways, such as the T cell receptor (TCR signaling pathway and microbial metabolism in diverse environments. This study facilitates understanding of the genetic architecture of the chicken spleen transcriptome, and has identified candidate genes for host response to APEC infection.

  14. Lethal infection by a novel reassortant H5N1 avian influenza A virus in a zoo-housed tiger.

    Science.gov (United States)

    He, Shang; Shi, Jianzhong; Qi, Xian; Huang, Guoqing; Chen, Hualan; Lu, Chengping

    2015-01-01

    In early 2013, a Bengal tiger (Panthera tigris) in a zoo died of respiratory distress. All specimens from the tiger were positive for HPAI H5N1, which were detected by real-time PCR, including nose swab, throat swab, tracheal swab, heart, liver, spleen, lung, kidney, aquae pericardii and cerebrospinal fluid. One stain of virus, A/Tiger/JS/1/2013, was isolated from the lung sample. Pathogenicity experiments showed that the isolate was able to replicate and cause death in mice. Phylogenetic analysis indicated that HA and NA of A/Tiger/JS/1/2013 clustered with A/duck/Vietnam/OIE-2202/2012 (H5N1), which belongs to clade 2.3.2.1. Interestingly, the gene segment PB2 shared 98% homology with A/wild duck/Korea/CSM-28/20/2010 (H4N6), which suggested that A/Tiger/JS/1/2013 is a novel reassortant H5N1 subtype virus. Immunohistochemical analysis also confirmed that the tiger was infected by this new reassortant HPAI H5N1 virus. Overall, our results showed that this Bengal tiger was infected by a novel reassortant H5N1, suggesting that the H5N1 virus can successfully cross species barriers from avian to mammal through reassortment.

  15. Human anti-plague monoclonal antibodies protect mice from Yersinia pestis in a bubonic plague model.

    Directory of Open Access Journals (Sweden)

    Xiaodong Xiao

    Full Text Available Yersinia pestis is the etiologic agent of plague that has killed more than 200 million people throughout the recorded history of mankind. Antibiotics may provide little immediate relief to patients who have a high bacteremia or to patients infected with an antibiotic resistant strain of plague. Two virulent factors of Y. pestis are the capsid F1 protein and the low-calcium response (Lcr V-protein or V-antigen that have been proven to be the targets for both active and passive immunization. There are mouse monoclonal antibodies (mAbs against the F1- and V-antigens that can passively protect mice in a murine model of plague; however, there are no anti-Yersinia pestis monoclonal antibodies available for prophylactic or therapeutic treatment in humans. We identified one anti-F1-specific human mAb (m252 and two anti-V-specific human mAb (m253, m254 by panning a naïve phage-displayed Fab library against the F1- and V-antigens. The Fabs were converted to IgG1s and their binding and protective activities were evaluated. M252 bound weakly to peptides located at the F1 N-terminus where a protective mouse anti-F1 mAb also binds. M253 bound strongly to a V-antigen peptide indicating a linear epitope; m254 did not bind to any peptide from a panel of 53 peptides suggesting that its epitope may be conformational. M252 showed better protection than m253 and m254 against a Y, pestis challenge in a plague mouse model. A synergistic effect was observed when the three antibodies were combined. Incomplete to complete protection was achieved when m252 was given at different times post-challenge. These antibodies can be further studied to determine their potential as therapeutics or prophylactics in Y. pestis infection in humans.

  16. The abundance threshold for plague as a critical percolation phenomenon

    DEFF Research Database (Denmark)

    Davis, S; Trapman, P; Leirs, H

    2008-01-01

    . However, no natural examples have been reported. The central question of interest in percolation theory 4 , the possibility of an infinite connected cluster, corresponds in infectious disease to a positive probability of an epidemic. Archived records of plague (infection with Yersinia pestis...

  17. BIRD FLU (AVIAN INFLUENZA)

    OpenAIRE

    Ali ACAR; Bulent BESIRBELLIOÐLU

    2005-01-01

    Avian influenza (bird flu) is a contagious disease of animals caused by influenza A viruses. These flu viruses occur naturally among birds. Actually, humans are not infected by bird flu viruses.. However, during an outbreak of bird flu among poultry, there is a possible risk to people who have contact infect birds or surface that have been contaminated with excreations from infected birds. Symptoms of bird flu in humans have ranged from typical flu-like symptoms to eye infections, pneumonia, ...

  18. Paleoclimate and bubonic plague: a forewarning of future risk?

    Directory of Open Access Journals (Sweden)

    McMichael Anthony J

    2010-08-01

    Full Text Available Abstract Pandemics of bubonic plague have occurred in Eurasia since the sixth century ad. Climatic variations in Central Asia affect the population size and activity of the plague bacterium's reservoir rodent species, influencing the probability of human infection. Using innovative time-series analysis of surrogate climate records spanning 1,500 years, a study in BMC Biology concludes that climatic fluctuations may have influenced these pandemics. This has potential implications for health risks from future climate change. See research article http://www.biomedcentral.com/1741-7007/8/112

  19. Synergetic effects of subgroup J avian leukosis virus and reticuloendotheliosis virus co-infection on growth retardation and immunosuppression in SPF chickens.

    Science.gov (United States)

    Dong, Xuan; Ju, Sidi; Zhao, Peng; Li, Yang; Meng, Fanfeng; Sun, Peng; Cui, Zhizhong

    2014-08-27

    To further understand the effect of co-infection of subgroup J avian leukosis virus (ALV-J) and reticuloendotheliosis virus (REV) in specific-pathogen-free (SPF) white leghorn chickens, the experiment was made to study the pathogenicity, the weight of body and immune organs, response to newcastle disease virus (NDV) and avian influenza virus subtype H9 (AIV-H9) vaccination. Chickens were randomly divided into four groups, which includes injection groups (REV, ALV-J, REV plus ALV-J), and negative control group. The pathogenesis experiments indicated that chickens co-infected with REV and ALV-J had significantly higher mortality rate than those of the chickens infected with REV or ALV-J alone (P0.05) on bursa and thymus over body wt ratios, however, chickens co-infected with REV and ALV-J had significantly lower titers than REV-infected chickens and ALV-J-infected chickens on HI antibody titers to ND and AIV-H9 after vaccination (P<0.05). These findings suggested that the co-infection of REV and ALV-J caused more serious growth retardation and immunosuppression in SPF chickens.

  20. Shedding light on avian influenza H4N6 infection in mallards: modes of transmission and implications for surveillance.

    Directory of Open Access Journals (Sweden)

    Kaci K VanDalen

    Full Text Available BACKGROUND: Wild mallards (Anas platyrhychos are considered one of the primary reservoir species for avian influenza viruses (AIV. Because AIV circulating in wild birds pose an indirect threat to agriculture and human health, understanding the ecology of AIV and developing risk assessments and surveillance systems for prevention of disease is critical. METHODOLOGY/PRINCIPAL FINDINGS: In this study, mallards were experimentally infected with an H4N6 subtype of AIV by oral inoculation or contact with an H4N6 contaminated water source. Cloacal swabs, oropharyngeal swabs, fecal samples, and water samples were collected daily and tested by real-time RT-PCR (RRT-PCR for estimation of viral shedding. Fecal samples had significantly higher virus concentrations than oropharyngeal or cloacal swabs and 6 month old ducks shed significantly more viral RNA than 3 month old ducks regardless of sample type. Use of a water source contaminated by AIV infected mallards, was sufficient to transmit virus to naïve mallards, which shed AIV at higher or similar levels as orally-inoculated ducks. CONCLUSIONS: Bodies of water could serve as a transmission pathway for AIV in waterfowl. For AIV surveillance purposes, water samples and fecal samples appear to be excellent alternatives or additions to cloacal and oropharyngeal swabbing. Furthermore, duck age (even within hatch-year birds may be important when interpreting viral shedding results from experimental infections or surveillance. Differential shedding among hatch-year mallards could affect prevalence estimates, modeling of AIV spread, and subsequent risk assessments.

  1. Different routes of inoculation impact infectivity and pathogenesis of H5N1 high pathogenicity avian influenza virus infection in chickens and domestic ducks.

    Science.gov (United States)

    Kwon, Y K; Swayne, D E

    2010-12-01

    The H5N1 type A influenza viruses classified as Qinghai-like virus (clade 2.2) are a unique lineage of type A influenza viruses with the capacity to produce significant disease and mortality in gallinaceous and anseriform birds, including domestic and wild ducks. The objective of this study was to determine the susceptibility and pathogenesis of chickens and domestic ducks to A/Whooper Swan/Mongolia/224/05 (H5N1) high pathogenicity avian influenza (HPAI) virus when administered through respiratory or alimentary routes of exposure. The chickens and ducks were more susceptible to the H5N1 HPAI virus, as evidenced by low infectious and lethal viral doses, when exposed by intranasal as compared to alimentary routes of inoculation (intragastric or oral-fed infected chicken meat). In the alimentary exposure pathogenesis study, pathologic changes included hemorrhage, necrosis, and inflammation in association with virus detection. These changes were generally observed in most of the visceral organs of chickens, between 2 and 4 days postinoculation (DPI), and are similar to lesions and virus localization seen in birds in natural cases or in experimental studies using the intranasal route. Alimentary exposure to the virus caused systemic infection in the ducks, characterized by moderate lymphocytic encephalitis, necrotized hepatitis, and pancreatitis with a corresponding demonstration of virus within the lesions. In both chickens and ducks with alimentary exposure, lesions, virus, or both were first demonstrated in the upper alimentary tract on 1 DPI, suggesting that the alimentary tract was the initial site affected upon consumption of infected meat or on gavage of virus in liquid medium. However, as demonstrated in the infectivity study in chickens, alimentary infection required higher exposure doses to produce infection as compared to intranasal exposure in chickens. These data suggest that upper respiratory exposure to H5N1 HPAI virus in birds is more likely to result in

  2. Associations of chicken Mx1 polymorphism with antiviral responses in avian influenza virus infected embryos and broilers.

    Science.gov (United States)

    Wang, Y; Brahmakshatriya, V; Lupiani, B; Reddy, S; Okimoto, R; Li, X; Chiang, H; Zhou, H

    2012-12-01

    Avian influenza virus (AIV) is a major respiratory disease of poultry that causes catastrophic losses to the poultry industry. The Mx protein has been shown to confer antiviral responses to influenza viruses in mice. One nonsynonymous substitution (S631N) in the chicken Mx protein is reported to be associated with resistance to AIV infection in vitro. The previous studies suggested controversy over whether this substitution in the Mx protein plays an important antiviral role in AIV infection in the chicken. It would be intriguing to investigate if the substitution is associated with resistance to AIV infection both in ovo and in vivo in chickens. In this study, the embryos and young chicks were generated from the cross of Mx1 heterozygous (S631N) parents with an expected segregating ratio of 1:2:1 in the progeny. A PCR length polymorphism was developed to genotype the Mx1 gene from 119 embryos and 48 chickens. The embryonated chicken eggs were inoculated with 10(6) 50% embryo infectious dose (EID(50)) H5N9 AIV on d 13. Hemagglutinating units in allantoic fluid were determined at 48 h postinoculation. For the in vivo study, twenty-four 1-wk-old broilers were inoculated with 10(6) EID(50) H5N3, and virus titers in lungs were evaluated at d 4 postinoculation. This is the first report revealing no significant association between Mx1 genotypes and low pathogenesis AIV infection both in ovo and in vivo in the chicken. Total RNA samples were isolated from chicken lung tissues in the in vivo study, and the Mx1 mRNA expression assay among 3 genotypes also suggested that only heterozygote birds had significantly greater expression with AIV infection than noninfected birds. A recombination breakpoint within Mx1 gene was also first identified, which has laid a solid foundation for further understanding biological function of the Mx1 gene in chickens. The current study provides valuable information on the effect of the Mx1 gene on the genetic resistance to AIV in chickens, and

  3. Avian influenza H5N1 virus infections in vaccinated commercial and backyard poultry in Egypt.

    Science.gov (United States)

    Hafez, M H; Arafa, A; Abdelwhab, E M; Selim, A; Khoulosy, S G; Hassan, M K; Aly, M M

    2010-08-01

    In this paper, we describe results from a high-pathogenic H5N1 avian influenza virus (AIV) surveillance program in previously H5-vaccinated commercial and family-backyard poultry flocks that was conducted from 2007 to 2008 by the Egyptian National Laboratory for Veterinary Quality Control on Poultry Production. The real-time reverse transcription PCR assay was used to detect the influenza A virus matrix gene and detection of the H5 and N1 subtypes was accomplished using a commercially available kit real-time reverse transcription PCR assay. The virus was detected in 35/3,610 (0.97%) and 27/8,682 (0.31%) of examined commercial poultry farms and 246/816 (30%) and 89/1,723 (5.2%) of backyard flocks in 2007 and 2008, respectively. Positive flocks were identified throughout the year, with the highest frequencies occurring during the winter months. Anti-H5 serum antibody titers in selected commercial poultry ranged from poultry in Egypt to combat H5N1 AIV, continuous circulation of the virus in vaccinated commercial and backyard poultry was reported and the efficacy of the vaccination using a challenge model with the current circulating field virus should be revised.

  4. SEROLOGICAL EVIDENCE OF AVIAN PARAMYXOVIRUS-2 INFECTION IN BACKYARD AND COMMERCIAL POULTRY BIRDS IN SAUDI ARABIA

    Directory of Open Access Journals (Sweden)

    A. N. ALKHALAF

    2009-07-01

    Full Text Available Serological survey was conducted to detect avian paramyxovirus serotype-2 (APMV-2 antibodies in commercial and backyard bird flocks, using Enzyme-linked immunosorbent assay (ELISA and haemagglutination inhibition (HI test. Sera were collected from 212 commercial and 56 backyard birds. Age of commercial birds ranged from one-day old to 62 weeks. In the backyard birds, seroprevalence of APVM-2 was 71.42 and 78.57%, whereas this seroprevalence was 52.35 and 60.84% using the HI test and the ELISA, respectively in commercial poultry birds. No antibodies against APMV-2 were detected in 1-5 days old chicks with either test. The HI test showed the highest positive samples (P<0.05 of APMV-2 in 19-35 days age group (58.33%, followed by age group 11-18 weeks (51.35% and 25-62 weeks (47.05%. Similarly, ELISA also showed the highest positive samples of APMV-2 (68.75% in 19-35 days age group (P<0.05, followed by age group 11-18 weeks (62.16% and 25-62 weeks (56.86%. In conclusion, this study indicated the presence of antibodies to APMV-2 among backyard and commercial poultry birds in Saudi Arabia.

  5. Brazilian avian metapneumovirus subtypes A and B: experimental infection of broilers and evaluation of vaccine efficacy

    Directory of Open Access Journals (Sweden)

    Márcia B. dos Santos

    2012-12-01

    Full Text Available Avian metapneumovirus (aMPV is a respiratory pathogen associated with the swollen head syndrome (SHS in chickens. In Brazil, live aMPV vaccines are currently used, but subtypes A and, mainly subtype B (aMPV/A and aMPV/B are still circulating. This study was conducted to characterize two Brazilian aMPV isolates (A and B subtypes of chicken origin. A challenge trial to explore the replication ability of the Brazilian subtypes A and B in chickens was performed. Subsequently, virological protection provided from an aMPV/B vaccine against the same isolates was analyzed. Upon challenge experiment, it was shown by virus isolation and real time PCR that aMPV/B could be detected longer and in higher amounts than aMPV/A. For the protection study, 18 one-day-old chicks were vaccinated and challenged at 21 days of age. Using virus isolation and real time PCR, no aMPV/A was detected in the vaccinated chickens, whereas one vaccinated chicken challenged with the aMPV/B isolate was positive. The results showed that aMPV/B vaccine provided a complete heterologous virological protection, although homologous protection was not complete in one chicken. Although only one aMPV/B positive chicken was detected after homologous vaccination, replication in vaccinated animals might allow the emergence of escape mutants.

  6. Microarray analysis following infection with highly pathogenic avian influenza H5N1 virus in naive and vaccinated SPF chickens

    Science.gov (United States)

    Avian influenza (AI) is a viral disease of poultry that remains a constant threat to commercial poultry throughout the world. Within the last few years, outbreaks of highly pathogenic avian influenza (HPAI) H5N1 have originated in Southeast Asia and spread to several European, Middle Eastern, and A...

  7. Avian anemia's

    Directory of Open Access Journals (Sweden)

    Raukar Jelena

    2005-01-01

    Full Text Available This paper deals with avian anemia's classified by MCHC/MCV and with types of anemia's. Father hematological and immunological research is needed to secure information on hematological parameters in different avian species at their earliest age. Anemia is a common clinical finding in birds because the avian erythrocyte half - life is much shorter than the mammalian. Therefore anemia should be determined as soon as possible. Researchers should standardize hematological parameters for every single avian species.

  8. Human avian influenza A (H5N1) virus infection in China

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Highly pathogenic influenza A (H5N1) virus causes a widespread poultry deaths worldwide. The first human H5N1 infected case was reported in Hong Kong Special Administrative Region of China in 1997. Since then, the virus re-emerged in 2003 and continues to infect people worldwide. Currently, over 400 human infections have been reported in more than 15 countries and mortality rate is greater than 60%. H5N1 viruses still pose a potential pandemic threat in the future because of the continuing global spread and evolution. Here, we summarize the epidemiological, clinical and virological characteristics of human H5N1 infection in China monitored and identified by our national surveillance systems.

  9. Determination of Original Infection Source of H7N9 Avian Influenza by Dynamical Model

    Science.gov (United States)

    Zhang, Juan; Jin, Zhen; Sun, Gui-Quan; Sun, Xiang-Dong; Wang, You-Ming; Huang, Baoxu

    2014-05-01

    H7N9, a newly emerging virus in China, travels among poultry and human. Although H7N9 has not aroused massive outbreaks, recurrence in the second half of 2013 makes it essential to control the spread. It is believed that the most effective control measure is to locate the original infection source and cut off the source of infection from human. However, the original infection source and the internal transmission mechanism of the new virus are not totally clear. In order to determine the original infection source of H7N9, we establish a dynamical model with migratory bird, resident bird, domestic poultry and human population, and view migratory bird, resident bird, domestic poultry as original infection source respectively to fit the true dynamics during the 2013 pandemic. By comparing the date fitting results and corresponding Akaike Information Criterion (AIC) values, we conclude that migrant birds are most likely the original infection source. In addition, we obtain the basic reproduction number in poultry and carry out sensitivity analysis of some parameters.

  10. Comparison of the efficacy of four antimicrobial treatment schemes against experimental Ornithobacterium rhinotracheale infection in turkey poults pre-infected with avian pneumovirus.

    Science.gov (United States)

    Marien, Maja; Nauwynck, Hans; Duchateau, Luc; Martel, An; Chiers, Koen; Devriese, Luc; Froyman, Robrecht; Decostere, Annemie

    2006-06-01

    The clinical efficacy of drinking-water administration of enrofloxacin for 3 and 5 days, amoxicillin for 5 days and florfenicol for 5 days for the treatment of respiratory disease induced by an experimental Ornithobacterium rhinotracheale infection in turkeys pre-infected with avian pneumovirus (APV) was assessed based on clinical, bacteriological and histopathological examinations. Experimental groups of 15 susceptible 3-week-old turkeys were each inoculated oculonasally with APV subtype A and 3 days later with susceptible O. rhinotracheale bacteria. Antimicrobial treatment started 1 day after O. rhinotracheale inoculation. After infection, the birds were examined and scored for clinical signs, swabbed daily and weighed at different times. Five birds were euthanized and examined for macroscopic lesions at necropsy at 5 days post bacterial inoculation, and the remainder at 15 days post bacterial inoculation. Samples of the turbinates, trachea, lungs, air sacs, heart and pericardium were collected for bacteriological and/or histological examination. Recovery from respiratory disease caused by an APV/O. rhinotracheale dual infection was most successful after enrofloxacin treatment, irrespective of treatment duration, followed by florfenicol. Amoxicillin treatment was not efficacious. Clinical signs and the number of O. rhinotracheale organisms re-isolated from the trachea and the different respiratory organs were significantly reduced by enrofloxacin treatment for 3 and 5 days. O. rhinotracheale bacteria were not re-isolated from the tracheas of the birds treated with enrofloxacin except for one bird in the 5-day group, as early as 1 day after medication onset. In the group treated with enrofloxacin for 5 days, O. rhinotracheale organisms with a higher minimal inhibitory concentration value (x8) were isolated starting 2 days following treatment onset, initially from a single turkey and subsequently from the other animals.

  11. Bibliographic Index to the Plague (1965-1970)

    Science.gov (United States)

    1975-11-18

    Shiko, Infection Promoting Activity of Htigh Molecular Weight Microbial Polysaccharides on Mouse Peritoneal Infections With irasteurella Pestis. .J...Plague Microbe 710. Admnov, A. K., Molecular Mechanisms of Information Exchange and the Variability of Organisms. In: Microbiol. and Inminol. of Dread...Bibliog.: 6refs. Ref.: R.J " Biologia , 99 2593 798. Bakhrakh, Ye. E., F. K. Drozdovskava and L. I. Glushko, The Affect of the Reduction-Oxidation State of

  12. Experimental infection of SPF and Korean native chickens with highly pathogenic avian influenza virus (H5N8).

    Science.gov (United States)

    Lee, Eun-Kyoung; Song, Byung-Min; Kang, Hyun-Mi; Woo, Sang-Hee; Heo, Gyeong-Beom; Jung, Suk Chan; Park, Yong Ho; Lee, Youn-Jeong; Kim, Jae-Hong

    2016-05-01

    In 2014, an H5N8 outbreak of highly pathogenic avian influenza (HPAI) occurred in South Korea. The H5N8 strain produced mild to moderate clinical signs and mortality rates in commercial chicken farms, especially Korean native chicken farms. To understand the differences between their pathogenicity in SPF chicken and Korean native chicken., we evaluated the mean bird lethal doses (BLD50) of the Korean representative H5N8 virus (A/broiler duck/Korea/Buan2/2014) The BLD50values of the H5N8 virus were 10(5.3)EID50 and 10(6.7)EID50 in SPF and Korean native chickens, respectively. In addition, the mean death time was much longer, and the viral titers in tissues of H5N8-infected chickens were significantly lower, in the Korean group than in the SPF group. These features of the H5N8 virus likely account for its mild-to-moderate pathogenicity in commercial chicken farms, especially Korean native chicken flocks, despite the fact that it is a highly pathogenic virus according to the OIE criteria. To improve current understanding and management of HPAI, pathogenic characterization of novel emerging viruses should be performed by natural route in major poultry species in each country.

  13. Genomic diversity of the Avian leukosis virus subgroup J gp85 gene in different organs of an infected chicken

    Science.gov (United States)

    Meng, Fanfeng; Li, Xue; Fang, Jian; Gao, Yalong; Zhu, Lilong; Xing, Guiju; Tian, Fu; Gao, Yali; Dong, Xuan; Chang, Shuang; Zhao, Peng; Liu, Zhihao

    2016-01-01

    The genomic diversity of Avian leukosis virus subgroup J (ALV-J) was investigated in an experimentally infected chicken. ALV-J variants in tissues from four different organs of the same bird were re-isolated in DF-1 cells, and their gp85 gene was amplified and cloned. Ten clones from each organ were sequenced and compared with the original inoculum strain, NX0101. The minimum homology of each organ ranged from 96.7 to 97.6%, and the lowest homology between organs was only 94.9%, which was much lower than the 99.1% homology of inoculum NX0101, indicating high diversity of ALV-J, even within the same bird. The gp85 mutations from the left kidney, which contained tumors, and the right kidney, which was tumor-free, had higher non-synonymous to synonymous mutation ratios than those in the tumor-bearing liver and lungs. Additionally, the mutational sites of gp85 gene in the kidney were similar, and they differed from those in the liver and lung, implying that organ- or tissue-specific selective pressure had a greater influence on the evolution of ALV-J diversity. These results suggest that more ALV-J clones from different organs and tissues should be sequenced and compared to better understand viral evolution and molecular epidemiology in the field. PMID:27456778

  14. Genomic diversity of the Avian leukosis virus subgroup J gp85 gene in different organs of an infected chicken.

    Science.gov (United States)

    Meng, Fanfeng; Li, Xue; Fang, Jian; Gao, Yalong; Zhu, Lilong; Xing, Guiju; Tian, Fu; Gao, Yali; Dong, Xuan; Chang, Shuang; Zhao, Peng; Cui, Zhizhong; Liu, Zhihao

    2016-12-30

    The genomic diversity of Avian leukosis virus subgroup J (ALV-J) was investigated in an experimentally infected chicken. ALV-J variants in tissues from four different organs of the same bird were re-isolated in DF-1 cells, and their gp85 gene was amplified and cloned. Ten clones from each organ were sequenced and compared with the original inoculum strain, NX0101. The minimum homology of each organ ranged from 96.7 to 97.6%, and the lowest homology between organs was only 94.9%, which was much lower than the 99.1% homology of inoculum NX0101, indicating high diversity of ALV-J, even within the same bird. The gp85 mutations from the left kidney, which contained tumors, and the right kidney, which was tumor-free, had higher non-synonymous to synonymous mutation ratios than those in the tumor-bearing liver and lungs. Additionally, the mutational sites of gp85 gene in the kidney were similar, and they differed from those in the liver and lung, implying that organ- or tissue-specific selective pressure had a greater influence on the evolution of ALV-J diversity. These results suggest that more ALV-J clones from different organs and tissues should be sequenced and compared to better understand viral evolution and molecular epidemiology in the field.

  15. Immunity to avian pneumovirus infection in turkeys following in ovo vaccination with an attenuated vaccine.

    Science.gov (United States)

    Worthington, Karen J; Sargent, Barbara A; Davelaar, F G; Jones, R C

    2003-03-28

    Fertile turkey eggs after 24 days of incubation were vaccinated in ovo with a commercial live attenuated subtype A avian pneumovirus (APV) vaccine. Hatchability was not adversely affected. When a high dose (10 times maximum commercial dose) of vaccine was tested in maternal antibody negative (MA-) eggs, mild clinical signs developed in a small proportion of the poults for 1-4 days only. Post-vaccination antibody titres at 3 weeks of age were significantly higher than those seen when the same dose was administered by eyedrop or spray at day-old. A low dose (end of shelf-life titre) of vaccine given to MA- eggs did not cause disease and vaccinated poults were 100% protected against virulent APV challenge at 3 or 5 weeks of age. Post-vaccination antibody titres reached significant levels at 3 weeks of age, whereas those from MA- poults vaccinated by spray at day-old with a similar low dose did not. In a 'worst-case' scenario, maternal antibody positive (MA+) poults vaccinated in ovo with the low dose were still 77% protected against clinical disease, despite lack of seroconversion. The recommended commercial dose of vaccine given to MA- eggs in ovo induced 100% protection against virulent APV challenge for up to 14 weeks of age, even though post-vaccination antibody titres had dropped to insignificant levels at this age. In ovo vaccination with a mixture of the recommended commercial doses of live APV and Newcastle disease (ND) vaccines had no detrimental affect on the efficacy of the APV vaccine. This is the first report of the successful use of an APV vaccine being given in ovo. The results indicate that for turkeys, in ovo vaccination with a live attenuated APV vaccine is safe and effective against virulent challenge and comparable with vaccination by conventional methods.

  16. Role of the lpxM lipid A biosynthesis pathway gene in pathogenicity of avian pathogenic Escherichia coli strain E058 in a chicken infection model.

    Science.gov (United States)

    Xu, Huiqing; Ling, Jielu; Gao, Qingqing; He, Hongbo; Mu, Xiaohui; Yan, Zhen; Gao, Song; Liu, Xiufan

    2013-10-25

    Lipopolysaccharide (LPS) is a major surface component of avian pathogenic Escherichia coli (APEC), and is a possible virulence factor in avian infections caused by this organism. The contribution of the lpxM gene, which encodes a myristoyl transferase that catalyzes the final step in lipid A biosynthesis, to the pathogenicity of APEC has not previously been assessed. In this study, an isogenic lpxM mutant, E058ΔlpxM, was constructed in APEC O2 strain E058 and then characterized. Structural analysis of lipid A from the parental strain and derived mutant showed that E058ΔlpxM lacked one myristoyl (C14:0) on its lipid A molecules. No differences were observed between the mutant and wild-type in a series of tests including growth rate in different broths and ability to survive in specific-pathogen-free chicken serum. However, the mutant showed significantly reduced invasion and intracellular survival in the avian macrophage HD11 cell line (Porgans of birds challenged with the wild-type strain were more severe than in birds infected with the mutant. However, the E058ΔlpxM mutant showed a similar sensitivity pattern to the parental strain following exposure to several hydrophobic reagents. These results indicate that the lpxM gene is important for the pathogenicity and biological activity of APEC strain E058.

  17. Up-Regulation of Pro-Inflammatory Cytokines and Chemokine Production in Avian Influenza H9N2 Virus-Infected Human Lung Epithelial Cell Line (A549).

    Science.gov (United States)

    Farzin, Hamidreza; Toroghi, Reza; Haghparast, Alireza

    2016-01-01

    Influenza H9N2 virus mostly infects avian species but poses a potential health risk to humans. Little is known about the mammalian host immune responses to H9N2 virus. To obtain insight into the innate immune responses of human lung epithelial cells to the avian H9N2 virus, the expressions of pro-inflammatory cytokines and chemokine in the human airway epithelial cells infected with avian H9N2 virus were examined by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA). H9N2 virus was able to cultivate in the human lung epithelial cell line (A549) and stimulate production of pro-inflammatory cytokines (IL-1β, IL-6) and chemokine (IL-8). Expressions of cytokine genes were up-regulated to a significantly higher level for IL-1β (p cytokines and chemokine. The findings in this study will broaden our understanding of host innate immune mechanisms and the pathogenesis of H9N2 influenza viruses in human respiratory epithelium.

  18. Quantitative iTRAQ LC-MS/MS Proteomics Reveals the Proteome Profiles of DF-1 Cells after Infection with Subgroup J Avian Leukosis Virus

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    Xiaofei Li

    2015-01-01

    Full Text Available Avian leukosis virus subgroup J (ALV-J is an avian oncogenic retrovirus that can induce various clinical tumors and has caused severe economic losses in China. To improve our understanding of the host cellular responses to virus infection and the pathogenesis of ALV-J infection, we applied isobaric tags for relative and absolute quantification (iTRAQ labeling coupled with multidimensional liquid chromatography-tandem mass spectrometry to detect the protein changes in DF-1 cells infected and mock-infected with ALV-J. A total of 75 cellular proteins were significantly changed, including 33 upregulated proteins and 42 downregulated proteins. The reliability of iTRAQ-LC MS/MS was confirmed via real-time PCR. Most of these proteins were related to the physiological functions of metabolic processes, biosynthetic processes, responses to stimuli, protein binding, signal transduction, cell cytoskeleton, and so forth. We also found some proteins that play important roles in apoptosis and oncogenicity. The differentially expressed proteins identified may provide valuable information to elucidate the pathogenesis of virus infection and virus-host interactions.

  19. Pathogenesis and transmissibility of highly (H7N1 and low (H7N9 pathogenic avian influenza virus infection in red-legged partridge (Alectoris rufa

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    Bertran Kateri

    2011-02-01

    Full Text Available Abstract An experimental infection with highly pathogenic avian influenza virus (HPAIV and low pathogenic avian influenza virus (LPAIV was carried out in red-legged partridges (Alectoris rufa in order to study clinical signs, gross and microscopic lesions, and viral distribution in tissues and viral shedding. Birds were infected with a HPAIV subtype H7N1 (A/Chicken/Italy/5093/1999 and a LPAIV subtype H7N9 (A/Anas crecca/Spain/1460/2008. Uninoculated birds were included as contacts in both groups. In HPAIV infected birds, the first clinical signs were observed at 3 dpi, and mortality started at 4 dpi, reaching 100% at 8 dpi. The presence of viral antigen in tissues and viral shedding were confirmed by immunohistochemistry and quantitative real time RT-PCR (qRRT-PCR, respectively, in all birds infected with HPAIV. However, neither clinical signs nor histopathological findings were observed in LPAIV infected partridges. In addition, only short-term viral shedding together with seroconversion was detected in some LPAIV inoculated animals. The present study demonstrates that the red-legged partridge is highly susceptible to the H7N1 HPAIV strain, causing severe disease, mortality and abundant viral shedding and thus contributing to the spread of a potential local outbreak of this virus. In contrast, our results concerning H7N9 LPAIV suggest that the red-legged partridge is not a reservoir species for this virus.

  20. Elucidation of the avian nucleolar proteome by quantitative proteomics using SILAC and changes in cells infected with the coronavirus infectious bronchitis virus.

    Science.gov (United States)

    Emmott, Edward; Smith, Catriona; Emmett, Stevan R; Dove, Brian K; Hiscox, Julian A

    2010-10-01

    The nucleolus is a dynamic subnuclear compartment involved in ribosome subunit biogenesis, regulation of cell stress and modulation of cellular growth and the cell cycle, among other functions. The nucleolus is composed of complex protein/protein and protein/RNA interactions. It is a target of virus infection with many viral proteins being shown to localize to the nucleolus during infection. Perturbations to the structure of the nucleolus and its proteome have been predicted to play a role in both cellular and infectious disease. Stable isotope labeling with amino acids in cell culture coupled to LC-MS/MS with bioinformatic analysis using Ingenuity Pathway Analysis was used to investigate whether the nucleolar proteome altered in virus-infected cells. In this study, the avian nucleolar proteome was defined in the absence and presence of virus, in this case the positive strand RNA virus, avian coronavirus infectious bronchitis virus. Data sets, potential protein changes and the functional consequences of virus infection were validated using independent assays. These demonstrated that specific rather than generic changes occurred in the nucleolar proteome in infectious bronchitis virus-infected cells.

  1. Investigation on the preventive strategies against two cases of human infection by avian influenza%两起人禽流感防控策略之思考

    Institute of Scientific and Technical Information of China (English)

    王慧琴; 房桂兰

    2014-01-01

    Objective The purpose of this study was to investigate the outbreak of avian flu,in order to develop scientific methods and strategies for prevention and control against human infection by avian influenza.Methods Epidemiological descriptive approach was adopted after two outbreaks of avian flu were reported in a town in Shapotou district.Analysis on prevention and control measures against human infection by bird flu was performed.Results During the first outbreak in 2006,because the health administrative department was inexperienced,resources were not uniformly integrated,and 218 staffs from ten units and excess resources were utilized.During the second outbreak in 2012,only 65 staffs from five units participated in dealing with the outbreak,which was much less than 2006.Conclusion Unified commanding,clear responsibilities,focused propaganda,and appropriate training are the most fundamental effective approach in prevention and control of highly pathogenic avian influenza infection.Unified commanding,integrated resources,and unified deployment by the health administrative department are the key to prevent human infection by avian influenza.%目的 探讨禽流感疫情发生后,科学防控人感染禽流感的方法和策略.方法 采取描述性的流行病学方法对沙坡头区某镇两次发生禽流感疫情后人感染禽流感防控措施进行分析.结果 2006年第一次禽流感疫情处置时,因卫生行政部门无经验,没有统一整合资源,参与处置疫情投入人员达218人、动用单位达10个,投入物资也较多,均明显多于2012年的65人、5个单位.结论 卫生行政部门统一指挥,整合资源,统一调配,加强人员防护及开展宣传教育是科学、高效防控人感染高致病性禽流感的关键.

  2. Plague in the genomic area.

    Science.gov (United States)

    Drancourt, M

    2012-03-01

    With plague being not only a subject of interest for historians, but still a disease of public health concern in several countries, mainly in Africa, there were hopes that analyses of the Yersinia pestis genomes would put an end to this deadly epidemic pathogen. Genomics revealed that Y. pestis isolates evolved from Yersinia pseudotuberculosis in Central Asia some millennia ago, after the acquisition of two Y. pestis-specific plasmids balanced genomic reduction parallel with the expansion of insertion sequences, illustrating the modern concept that, except for the acquisition of plasmid-borne toxin-encoding genes, the increased virulence of Y. pestis resulted from gene loss rather than gene acquisition. The telluric persistence of Y. pestis reminds us of this close relationship, and matters in terms of plague epidemiology. Whereas biotype Orientalis isolates spread worldwide, the Antiqua and Medievalis isolates showed more limited expansion. In addition to animal ectoparasites, human ectoparasites such as the body louse may have participated in this expansion and in devastating historical epidemics. The recent analysis of a Black Death genome indicated that it was more closely related to the Orientalis branch than to the Medievalis branch. Modern Y. pestis isolates grossly exhibit the same gene content, but still undergo micro-evolution in geographically limited areas by differing in the genome architecture, owing to inversions near insertion sequences and the stabilization of the YpfPhi prophage in Orientalis biotype isolates. Genomics have provided several new molecular tools for the genotyping and phylogeographical tracing of isolates and description of plague foci. However, genomics and post-genomics approaches have not yet provided new tools for the prevention, diagnosis and management of plague patients and the plague epidemics still raging in some sub-Saharan countries.

  3. An Evaluation of the Infection Status and Source of Subgroup J Avian Leukosis Virus in Cloned Free-Range Layers

    Institute of Scientific and Technical Information of China (English)

    ZHANG Pei-pei; LIU Shao-qiong; WANG Jian; WANG Bo; ZHAO Cheng-di; ZHANG Yong-guang; SUN Shu-hong

    2013-01-01

    In recent years, subgroup J avian leukosis virus (ALV-J) has been found to frequently infect layers in China. This virus is responsible for economic losses due to both mortality and decreased performance in chickens. In this study, 45-d-old cloned free-range layers were suspected to be infected with ALV and other immunosuppressive diseases because their feathers were unkempt and their growth rate was impaired. To estimate the infection status and determine the source of ALV-J in the flock, 30 cloacal swabs were randomly collected to measure the p27 antigen level by enzyme-linked immunosorbent assay (ELISA). Among the birds that were tested, 87%(26/30) were positive. In addition, 6 anticoagulant blood samples were aseptically collected at random from the flock when the layers were 60 d old. These samples were centrifuged to obtain the leukocytes, which were then used to inoculate chicken embryo fibroblast (CEF) cells for the identification of ALV-J by indirect immunofluorescence (IFA). Of the samples tested, 100%(6/6) were positive. The flock’s production performance was also investigated, and 10 layers were necropsied to evaluate pathological changes at 115 d of age. The flock never laid eggs even though they reached the age of the first laying (110 d). Furthermore, there were pathological changes present, including atrophy of the thymus and bursa of Fabricius, undeveloped ovaries, glandular stomach haemorrhage, and hepatosplenomegaly. Paraffin-embedded sections of intumescent liver and spleen were prepared for antigen localisation using IFA. Positive signals were prevalent in paraffin-embedded sections of the intumescent liver and spleen. Furthermore, provirus DNA was extracted from 4 cloned free-range layers, and 2 paternal parents (HR native cocks), and the gp85 gene of ALV-J was amplified by PCR to analyse the genetic variation. The results of the autogenous variation analysis showed that the 6 strains were 98.5-99.7%homologous. This study indicated that

  4. Pathogenicity of Highly Pathogenic Avian Influenza Virus H5N1 in Naturally Infected Poultry in Egypt.

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    Ibrahim Thabet Hagag

    Full Text Available Highly pathogenic avian influenza virus (HPAIV H5N1 has been endemic in Egypt since 2006, and there is increasing concern for its potential to become highly transmissible among humans. Infection by HPAIV H5N1 has been described in experimentally challenged birds. However, the pathogenicity of the H5N1 isolated in Egypt has never been reported in naturally infected chickens and ducks. Here we report a 2013 outbreak of HPAIV H5N1 in commercial poultry farms and backyards in Sharkia Province, Egypt. The main symptoms were ecchymosis on the shanks and feet, cyanosis of the comb and wattles, subcutaneous edema of the head and neck for chickens, and nervous signs (torticollis for ducks. Within 48-72 hrs of the onset of illness, the average mortality rates were 22.8-30% and 28.5-40% in vaccinated chickens and non-vaccinated ducks, respectively. Tissue samples of chickens and ducks were collected for analyses with cross-section immunohistochemistry and real-time RT-PCR for specific viral RNA transcripts. While viral RNA was detected in nearly all tissues and sera collected, viral nucleoprotein was detected almost ubiquitously in all tissues, including testis. Interestingly, viral antigen was also observed in endothelial cells of most organs in chickens, and clearly detected in the trachea and brain in particular. Viral nucleoprotein was also detected in mononuclear cells of various organs, especially pulmonary tissue. We performed phylogenetic analyses and compared the genomic sequences of the hemagglutinin (HA and nonstructural proteins (NS among the isolated viruses, the HPAIV circulated in Egypt in the past and currently, and some available vaccine strains. Further analysis of deduced amino acids of both HA and NS1 revealed that our isolates carried molecular determinants of HPAIV, including the multibasic amino acids (PQGERRRK/KR*GLF in the cleavage site in HA and glutamate at position 92 (D92E in NS1. This is the first report of the pathogenicity

  5. Long-Term Effect of Serial Infections with H13 and H16 Low-Pathogenic Avian Influenza Viruses in Black-Headed Gulls

    Science.gov (United States)

    Verhagen, Josanne H.; van Amerongen, Geert; van de Bildt, Marco; Majoor, Frank; Fouchier, Ron A. M.

    2015-01-01

    ABSTRACT Infections of domestic and wild birds with low-pathogenic avian influenza viruses (LPAIVs) have been associated with protective immunity to subsequent infection. However, the degree and duration of immunity in wild birds from previous LPAIV infection, by the same or a different subtype, are poorly understood. Therefore, we inoculated H13N2 (A/black-headed gull/Netherlands/7/2009) and H16N3 (A/black-headed gull/Netherlands/26/2009) LPAIVs into black-headed gulls (Chroicocephalus ridibundus), their natural host species, and measured the long-term immune response and protection against one or two reinfections over a period of >1 year. This is the typical interval between LPAIV epizootics in wild birds. Reinfection with the same virus resulted in progressively less virus excretion, with complete abrogation of virus excretion after two infections for H13 but not H16. However, reinfection with the other virus affected neither the level nor duration of virus excretion. Virus excretion by immunologically naive birds did not differ in total levels of excreted H13 or H16 virus between first- and second-year birds, but the duration of H13 excretion was shorter for second-year birds. Furthermore, serum antibody levels did not correlate with protection against LPAIV infection. LPAIV-infected gulls showed no clinical signs of disease. These results imply that the epidemiological cycles of H13 and H16 in black-headed gulls are relatively independent from each other and depend mainly on infection of first-year birds. IMPORTANCE Low-pathogenic avian influenza viruses (LPAIVs) circulate mainly in wild water birds but are occasionally transmitted to other species, including humans, where they cause subclinical to fatal disease. To date, the effect of LPAIV-specific immunity on the epidemiology of LPAIV in wild birds is poorly understood. In this study, we investigated the effect of H13 and H16 LPAIV infection in black-headed gulls on susceptibility and virus excretion of

  6. A plague epizootic in the black-tailed prairie dog (Cynomys ludovicianus).

    Science.gov (United States)

    Pauli, Jonathan N; Buskirk, Steven W; Williams, Elizabeth S; Edwards, William H

    2006-01-01

    Plague is the primary cause for the rangewide decline in prairie dog (Cynomys spp.) distribution and abundance, yet our knowledge of plague dynamics in prairie dog populations is limited. Our understanding of the effects of plague on the most widespread species, the black-tailed prairie dog (C. ludovicianus), is particularly weak. During a study on the population biology of black-tailed prairie dogs in Wyoming, USA, plague was detected in a colony under intensive monitoring, providing a unique opportunity to quantify various consequences of plague. The epizootic reduced juvenile abundance by 96% and adult abundance by 95%. Of the survivors, eight of nine adults and one of eight juveniles developed antibodies to Yersinia pestis. Demographic groups appeared equally susceptible to infection, and age structure was unaffected. Survivors occupied three small coteries and exhibited improved body condition, but increased flea infestation compared to a neighboring, uninfected colony. Black-tailed prairie dogs are capable of surviving a plague epizootic and reorganizing into apparently functional coteries. Surviving prairie dogs may be critical in the repopulation of plague-decimated colonies and, ultimately, the evolution of plague resistance.

  7. Spread of plague among black-tailed prairie dogs is associated with colony spatial characteristics

    Science.gov (United States)

    Johnson, T.L.; Cully, J.F.; Collinge, S.K.; Ray, C.; Frey, C.M.; Sandercock, B.K.

    2011-01-01

    Sylvatic plague (Yersinia pestis) is an exotic pathogen that is highly virulent in black-tailed prairie dogs (Cynomys ludovicianus) and causes widespread colony losses and individual mortality rates >95%. We investigated colony spatial characteristics that may influence inter-colony transmission of plague at 3 prairie dog colony complexes in the Great Plains. The 4 spatial characteristics we considered include: colony size, Euclidean distance to nearest neighboring colony, colony proximity index, and distance to nearest drainage (dispersal) corridor. We used multi-state mark-recapture models to determine the relationship between these colony characteristics and probability of plague transmission among prairie dog colonies. Annual mapping of colonies and mark-recapture analyses of disease dynamics in natural colonies led to 4 main results: 1) plague outbreaks exhibited high spatial and temporal variation, 2) the site of initiation of epizootic plague may have substantially influenced the subsequent inter-colony spread of plague, 3) the long-term effect of plague on individual colonies differed among sites because of how individuals and colonies were distributed, and 4) colony spatial characteristics were related to the probability of infection at all sites although the relative importance and direction of relationships varied among sites. Our findings suggest that conventional prairie dog conservation management strategies, including promoting large, highly connected colonies, may need to be altered in the presence of plague. ?? 2011 The Wildlife Society.

  8. Origin and characteristics of internal genes affect infectivity of the novel avian-origin influenza A (H7N9 virus.

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    Yan Feng

    Full Text Available BACKGROUND: Human infection with a novel avian-origin influenza A (H7N9 virus occurred continuously in China during the first half of 2013, with high infectivity and pathogenicity to humans. In this study, we investigated the origin of internal genes of the novel H7N9 virus and analyzed the relationship between internal genes and infectivity of the virus. METHODOLOGY AND PRINCIPAL FINDINGS: We tested the environmental specimens using real-time RT-PCR assays and isolated five H9N2 viruses from specimens that were positive for both H7 and H9. Results of recombination and phylogeny analysis, performed based on the entire sequences of 221 influenza viruses, showed that one of the Zhejiang avian H9N2 isolates, A/environment/Zhejiang/16/2013, shared the highest identities on the internal genes with the novel H7N9 virus A/Anhui/1/2013, ranging from 98.98% to 100%. Zhejiang avian H9N2 isolates were all reassortant viruses, by acquiring NS gene from A/chicken/Dawang/1/2011-like viruses and other five internal genes from A/brambling/Beijing/16/2012-like viruses. Compared to A/Anhui/1/2013 (H7N9, the homology on the NS gene was 99.16% with A/chicken/Dawang/1/2011, whereas only 94.27-97.61% with A/bramnling/Beijing/16/2012-like viruses. Analysis on the relationship between internal genes and the infectivity of novel H7N9 viruses were performed by comparing amino acid sequences with the HPAI H5N1 viruses, the H9N2 and the earlier H7N9 avian influenza viruses. There were nine amino acids on the internal genes found to be possibly associated with the infectivity of the novel H7N9 viruses. CONCLUSIONS: These findings indicate that the internal genes, sharing the highest similarities with A/environment/Zhejiang/16/2013-like (H9N2 viruses, may affect the infectivity of the novel H7N9 viruses.

  9. Immunoregulatory effects of Taishan Pinus massoniana pollen polysaccharide on chicks co-infected with avian leukosis virus and Bordetella avium early in ovo.

    Science.gov (United States)

    Guo, Fanxia; Xue, Cong; Wu, Cun; Zhao, Xue; Qu, Tinghe; He, Xiaohua; Guo, Zhongkun; Zhu, Ruiliang

    2014-04-01

    In recent years, co-infection of chicken embryos with immunosuppressive viruses and bacteria occurs with an annually increasing frequency. Consequently, studies on new and safe immunoregulators, especially plant polysaccharides, have become a popular topic in the poultry industry. In the present study, we selected 300 specific pathogen free embryonated eggs, which were injected with subgroup B avian leukosis virus (ALV-B) and Bordetella avium (B. avium) to establish an artificial co-infection model. The chicks that hatched from these co-infected embryonated eggs were treated with Taishan Pinus massoniana pollen polysaccharide (TPPPS). Results indicated that relevant indices in the co-infection group were significantly lower than that in B. avium-only group. Furthermore, pathogenicity of B. avium was exacerbated, with the chicks exhibiting decreased body weights. The TPPPS groups exhibited gradual improvements in immune function and developmental status. Therefore, in terms of improving immunologic function and production performance, TPPPS could be used as immunoregulator for immune responses.

  10. Effects of polysaccharide on chicks co-infected with Bordetella avium and Avian leukosis virus.

    Science.gov (United States)

    Guo, Fanxia; Xue, Cong; Wu, Cun; Zhao, Xue; Qu, Tinghe; He, Xiaohua; Guo, Zhongkun; Zhu, Ruiliang

    2014-08-30

    Chicks' co-infection with immunosuppressive virus and bacteria seriously threaten the development of the poultry industry. In this study, a model was established in which chicks were injected with either subgroup B ALV (ALV-B)+Bordetella avium (B. avium), or ALV-B+B. avium+Taishan Pinus massoniana pollen polysaccharide (TPPPS), or B. avium only, or B. avium+TPPPS. The data showed that the group injected with ALV-B and B. avium exhibited significant inhibition of the immune function and therefore increased pathogenicity compared with the group injected with B. avium-only. Application of TPPPS effectively alleviated immunosuppression, and body weights increased sharply in the TPPPS groups compared with non-TPPPS groups. To some extent, TPPPS may reduce the proliferation of ALV-B. These results suggest that Pinus pollen polysaccharides are beneficial treating co-infections with immunosuppressive virus and bacteria and therefore have potential for development into safe and effective immunoregulator.

  11. Field-based estimates of avian mortality from West Nile virus infection.

    Science.gov (United States)

    Ward, Michael P; Beveroth, Tara A; Lampman, Richard; Raim, Arlo; Enstrom, David; Novak, Robert

    2010-11-01

    One of the unique characteristics of West Nile virus (WNV) in North America is the large number of bird species for which the virus can be fatal. WNV mortality has been documented through experimental infections of captive birds and necropsies of free-ranging birds. Investigations of WNV-related mortality in wild birds often focus on species with dramatic population declines (e.g., American Crow, Corvus brachyrhynchos); however, few studies have addressed WNV-related mortality in species not exhibiting marked population declines since the arrival of WNV. We conducted a mark-recapture study of 204 Northern Cardinals (Cardinalis cardinalis) in an area with endemic WNV activity to estimate WNV-related mortality. Previous research has shown that once a bird is infected and recovers from WNV it develops antibodies making it resistant to future infection. Assuming that mortality risks from non-WNV causes were the same for individuals with (had been exposed to WNV) and without antibodies (had not been exposed to WNV), we compared the survival rates of birds with and without WNV antibodies to estimate the impact of WNV on wild birds. An information theoretic approach was used, and the apparent survival was found to be 34.6% lower for individuals without antibodies during the period when WNV was most active (July-September). However, the apparent survival rate was 9.0% higher for individuals without antibodies over the rest of the year. These differences in apparent survival suggest that WNV increases mortality during the WNV season and that chronic effects of WNV infection may also be contributing to mortality. Although WNV appears to have increased mortality rates within the population, population trend data do not indicate declines, suggesting that some cardinal populations can compensate for WNV-related mortality.

  12. Avian influenza viruses that cause highly virulent infections in humans exhibit distinct replicative properties in contrast to human H1N1 viruses

    Science.gov (United States)

    Simon, Philippe F.; de La Vega, Marc-Antoine; Paradis, Éric; Mendoza, Emelissa; Coombs, Kevin M.; Kobasa, Darwyn; Beauchemin, Catherine A. A.

    2016-04-01

    Avian influenza viruses present an emerging epidemiological concern as some strains of H5N1 avian influenza can cause severe infections in humans with lethality rates of up to 60%. These have been in circulation since 1997 and recently a novel H7N9-subtyped virus has been causing epizootics in China with lethality rates around 20%. To better understand the replication kinetics of these viruses, we combined several extensive viral kinetics experiments with mathematical modelling of in vitro infections in human A549 cells. We extracted fundamental replication parameters revealing that, while both the H5N1 and H7N9 viruses replicate faster and to higher titers than two low-pathogenicity H1N1 strains, they accomplish this via different mechanisms. While the H7N9 virions exhibit a faster rate of infection, the H5N1 virions are produced at a higher rate. Of the two H1N1 strains studied, the 2009 pandemic H1N1 strain exhibits the longest eclipse phase, possibly indicative of a less effective neuraminidase activity, but causes infection more rapidly than the seasonal strain. This explains, in part, the pandemic strain’s generally slower growth kinetics and permissiveness to accept mutations causing neuraminidase inhibitor resistance without significant loss in fitness. Our results highlight differential growth properties of H1N1, H5N1 and H7N9 influenza viruses.

  13. Protocatechuic acid, a novel active substance against avian influenza virus H9N2 infection.

    Directory of Open Access Journals (Sweden)

    Changbo Ou

    Full Text Available Influenza virus H9N2 subtype has triggered co-infection with other infectious agents, resulting in huge economical losses in the poultry industry. Our current study aims to evaluate the antiviral activity of protocatechuic acid (PCA against a virulent H9N2 strain in a mouse model. 120 BALB/c mice were divided into one control group, one untreated group, one 50 mg/kg amantadine hydrochloride-treated group and three PCA groups treated 12 hours post-inoculation with 40, 20 or 10 mg/kg PCA for 7 days. All the infected animals were inoculated intranasally with 0.2 ml of a A/Chicken/Hebei/4/2008(H9N2 inoculum. A significant body weight loss was found in the 20 mg/kg and 40 mg/kg PCA-treated and amantadine groups as compared to the control group. The 14 day survivals were 94.4%, 100% and 95% in the PCA-treated groups and 94.4% in the amantadine hydrochloride group, compared to less than 60% in the untreated group. Virus loads were less in the PCA-treated groups compared to the amantadine-treated or the untreated groups. Neutrophil cells in BALF were significantly decreased while IFN-γ, IL-2, TNF-α and IL-6 decreased significantly at days 7 in the PCA-treated groups compared to the untreated group. Furthermore, a significantly decreased CD4+/CD8+ ratio and an increased proportion of CD19 cells were observed in the PCA-treated groups and amantadine-treated group compared to the untreated group. Mice administered with PCA exhibited a higher survival rate and greater viral clearance associated with an inhibition of inflammatory cytokines and activation of CD8+ T cell subsets. PCA is a promising novel agent against bird flu infection in the poultry industry.

  14. Clinical characteristics of 26 human cases of highly pathogenic avian influenza A (H5N1 virus infection in China.

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    Hongjie Yu

    Full Text Available BACKGROUND: While human cases of highly pathogenic avian influenza A (H5N1 virus infection continue to increase globally, available clinical data on H5N1 cases are limited. We conducted a retrospective study of 26 confirmed human H5N1 cases identified through surveillance in China from October 2005 through April 2008. METHODOLOGY/PRINCIPAL FINDINGS: Data were collected from hospital medical records of H5N1 cases and analyzed. The median age was 29 years (range 6-62 and 58% were female. Many H5N1 cases reported fever (92% and cough (58% at illness onset, and had lower respiratory findings of tachypnea and dyspnea at admission. All cases progressed rapidly to bilateral pneumonia. Clinical complications included acute respiratory distress syndrome (ARDS, 81%, cardiac failure (50%, elevated aminotransaminases (43%, and renal dysfunction (17%. Fatal cases had a lower median nadir platelet count (64.5 x 10(9 cells/L vs 93.0 x 10(9 cells/L, p = 0.02, higher median peak lactic dehydrogenase (LDH level (1982.5 U/L vs 1230.0 U/L, p = 0.001, higher percentage of ARDS (94% [n = 16] vs 56% [n = 5], p = 0.034 and more frequent cardiac failure (71% [n = 12] vs 11% [n = 1], p = 0.011 than nonfatal cases. A higher proportion of patients who received antiviral drugs survived compared to untreated (67% [8/12] vs 7% [1/14], p = 0.003. CONCLUSIONS/SIGNIFICANCE: The clinical course of Chinese H5N1 cases is characterized by fever and cough initially, with rapid progression to lower respiratory disease. Decreased platelet count, elevated LDH level, ARDS and cardiac failure were associated with fatal outcomes. Clinical management of H5N1 cases should be standardized in China to include early antiviral treatment for suspected H5N1 cases.

  15. Differential sensitivity of human, avian, and equine influenza A viruses to a glycoprotein inhibitor of infection: selection of receptor specific variants.

    Science.gov (United States)

    Rogers, G N; Pritchett, T J; Lane, J L; Paulson, J C

    1983-12-01

    Human and animal (avian and equine) influenza A virus isolates of the H3 serotype exhibit marked differences in their ability to bind specific sialyloligosaccharide sequences that serve as cell surface receptor determinants (G. Rogers and J. Paulson, 1983, Virology 127, 361-373). Whereas human isolates of this subtype strongly agglutinate enzymatically modified human erythrocytes containing the terminal SA alpha 2,6Gal sequence, avian and equine isolates preferentially agglutinate erythrocytes bearing the SA alpha 2, 3Gal sequence. As shown in this report, a glycoprotein found in horse serum, alpha 2-macroglobulin, is a potent inhibitor of viral adsorption to the cell surface for human H3 isolates. In contrast, avian and equine isolates are poorly inhibited suggesting a correlation between receptor specificity and inhibitor sensitivity. Growth of a human H3 isolate (A/Memphis/102/72) on MDCK cells in the presence of horse serum resulted in an overall shift in the virus receptor specificity from preferential binding of the SA alpha 2,6Gal linkage to preferential binding of the SA alpha 2,3Gal linkage characteristic of avian and equine isolates. Clonally isolated variants of A/Memphis/102/72 grown in the presence or absence of horse serum exhibited binding properties that account for those observed in the field isolates. Clones which preferentially bound the SA alpha 2,6Gal linkage, like the parent human virus, were very sensitive to inhibition of hemagglutination by horse serum and equine alpha 2-macroglobulin. In contrast, receptor variants which preferentially bound the SA alpha 2,3Gal linkage, like the avian and equine isolate, were insensitive to such inhibitors. None of the variants was very sensitive to inhibition of hemagglutination by human alpha 2-macroglobulin. These results suggest that the presence, in vivo, of a glycoprotein inhibitor such as equine alpha 2-macroglobulin could suppress infection of influenza viruses bearing an H3 hemagglutinin with a SA

  16. Avian influenza virus

    Science.gov (United States)

    Avian influenza (AI) is caused by type A influenza virus, a member of the Orthomyxoviridae family. AI viruses are serologically categorized into 16 hemagglutinin (H1-H16) and 9 neuraminidase (N1-N9) subtypes. All subtypes have been identified in birds. Infections by AI viruses have been reported in ...

  17. Protection and differentiation of infected from vaccinated animals by an inactivated recombinant Newcastle disease virus/avian influenza H5 vaccine.

    Science.gov (United States)

    Lozano-Dubernard, Bernardo; Soto-Priante, Ernesto; Sarfati-Mizrahi, David; Castro-Peralta, Felipa; Flores-Castro, Ricardo; Loza-Rubio, Elizabeth; Gay-Gutiérrez, Manuel

    2010-03-01

    Specific-pathogen-free chickens immunized at 14 days of age with either an inactivated recombinant Newcastle disease virus-LaSota/avian influenza H5 (K-rNDV-LS/AI-H5) vaccine or a killed Newcastle disease/avian influenza whole-virus vaccine (K-ND/AI) were protected from disease when challenged with either A/chicken/Queretaro/14588-19/95 (H5N2), a high pathogenicity avian influenza virus (HPAIV) strain isolated in Mexico in 1995, or with a Mexican velogenic viscerotropic Newcastle disease virus (VVNDV) strain 21 days postvaccination. All nonvaccinated chickens challenged with HPAIV or VVNDV succumbed to disease, while those vaccinated with K-rNDV-LS/AI-H5 or K-ND/AI were protected from severe clinical signs and death. Both vaccines induced hemagglutination-inhibition (HI) antibody responses against NDV and AIV. Antibodies against AIV nucleoprotein were not detected by enzyme-linked immunosorbent assay (ELISA) in birds vaccinated with the inactivated rNDV-LS/AI-H5 vaccine. These chickens became positive for AIV antibodies by ELISA only after challenge with HPAIV. The data clearly indicate that the inactivated rNDV-LS/AI-H5 vaccine confers protection comparable to that of the conventional killed whole-virus vaccine against both NDV and AIV, while still allowing differentiation of infected from vaccinated animals by HI and ELISA tests.

  18. Experimentally infected domestic ducks show efficient transmission of Indonesian H5N1 highly pathogenic avian influenza virus, but lack persistent viral shedding.

    Science.gov (United States)

    Wibawa, Hendra; Bingham, John; Nuradji, Harimurti; Lowther, Sue; Payne, Jean; Harper, Jenni; Junaidi, Akhmad; Middleton, Deborah; Meers, Joanne

    2014-01-01

    Ducks are important maintenance hosts for avian influenza, including H5N1 highly pathogenic avian influenza viruses. A previous study indicated that persistence of H5N1 viruses in ducks after the development of humoral immunity may drive viral evolution following immune selection. As H5N1 HPAI is endemic in Indonesia, this mechanism may be important in understanding H5N1 evolution in that region. To determine the capability of domestic ducks to maintain prolonged shedding of Indonesian clade 2.1 H5N1 virus, two groups of Pekin ducks were inoculated through the eyes, nostrils and oropharynx and viral shedding and transmission investigated. Inoculated ducks (n = 15), which were mostly asymptomatic, shed infectious virus from the oral route from 1 to 8 days post inoculation, and from the cloacal route from 2-8 dpi. Viral ribonucleic acid was detected from 1-15 days post inoculation from the oral route and 1-24 days post inoculation from the cloacal route (cycle threshold Indonesian clade 2.1 H5N1 highly pathogenic avian influenza virus does not persist in individual ducks after acute infection.

  19. Quantification of bird-to-bird and bird-to-human infections during 2013 novel H7N9 avian influenza outbreak in China.

    Science.gov (United States)

    Hsieh, Ying-Hen; Wu, Jianhong; Fang, Jian; Yang, Yong; Lou, Jie

    2014-01-01

    From February to May, 2013, 132 human avian influenza H7N9 cases were identified in China resulting in 37 deaths. We developed a novel, simple and effective compartmental modeling framework for transmissions among (wild and domestic) birds as well as from birds to human, to infer important epidemiological quantifiers, such as basic reproduction number for bird epidemic, bird-to-human infection rate and turning points of the epidemics, for the epidemic via human H7N9 case onset data and to acquire useful information regarding the bird-to-human transmission dynamics. Estimated basic reproduction number for infections among birds is 4.10 and the mean daily number of human infections per infected bird is 3.16*10-5 [3.08*10-5, 3.23*10-5]. The turning point of 2013 H7N9 epidemic is pinpointed at April 16 for bird infections and at April 9 for bird-to-human transmissions. Our result reveals very low level of bird-to-human infections, thus indicating minimal risk of widespread bird-to-human infections of H7N9 virus during the outbreak. Moreover, the turning point of the human epidemic, pinpointed at shortly after the implementation of full-scale control and intervention measures initiated in early April, further highlights the impact of timely actions on ending the outbreak. This is the first study where both the bird and human components of an avian influenza epidemic can be quantified using only the human case data.

  20. Quantification of bird-to-bird and bird-to-human infections during 2013 novel H7N9 avian influenza outbreak in China.

    Directory of Open Access Journals (Sweden)

    Ying-Hen Hsieh

    Full Text Available From February to May, 2013, 132 human avian influenza H7N9 cases were identified in China resulting in 37 deaths. We developed a novel, simple and effective compartmental modeling framework for transmissions among (wild and domestic birds as well as from birds to human, to infer important epidemiological quantifiers, such as basic reproduction number for bird epidemic, bird-to-human infection rate and turning points of the epidemics, for the epidemic via human H7N9 case onset data and to acquire useful information regarding the bird-to-human transmission dynamics. Estimated basic reproduction number for infections among birds is 4.10 and the mean daily number of human infections per infected bird is 3.16*10-5 [3.08*10-5, 3.23*10-5]. The turning point of 2013 H7N9 epidemic is pinpointed at April 16 for bird infections and at April 9 for bird-to-human transmissions. Our result reveals very low level of bird-to-human infections, thus indicating minimal risk of widespread bird-to-human infections of H7N9 virus during the outbreak. Moreover, the turning point of the human epidemic, pinpointed at shortly after the implementation of full-scale control and intervention measures initiated in early April, further highlights the impact of timely actions on ending the outbreak. This is the first study where both the bird and human components of an avian influenza epidemic can be quantified using only the human case data.

  1. MOLECULAR AND EVOLUTIONARY INSIGHTS INTO YERSINIA PESTIS; HARBINGER OF PLAGUE

    Directory of Open Access Journals (Sweden)

    Stephen Anderson

    2013-10-01

    Full Text Available Plague has been the scourge of mankind for millennia; yet it was not until the late 18th Century that its causative agent was identified. Prokaryotic Y. pestis is responsible for plague; bacilli are consumed through arthropod feeding on infected rodential reservoirs. Arthropod uptake is essential for transmission as the bacilli proliferate within their gut before being refluxed into new mammalian hosts. Genomic analysis has elucidated the mechanisms facilitating this cycle along with the means by which bacilli acquire their characteristic virulence. Increasing our understanding of the evolution of Y. pestis provides putative avenues for future research. Whilst plague is considered a disease of the past by many, it interaction with humanity continues across various geographic foci. The rise of antibiotic resistant bacteria threatens to bring this ancient foe once again to the fore through the acquisition of drug resistance. This review will detail notable advances of the past decade enabling the elusive possibility of a universal vaccine for the three manifestations of plague. Development of suitable vaccines before drug resistant strains emerge is paramount. Researchers are pitted in an on-going race against bacterial evolution.

  2. Heptad repeat 2-based peptides inhibit avian sarcoma and leukosis virus subgroup a infection and identify a fusion intermediate.

    Science.gov (United States)

    Netter, Robert C; Amberg, Sean M; Balliet, John W; Biscone, Mark J; Vermeulen, Arwen; Earp, Laurie J; White, Judith M; Bates, Paul

    2004-12-01

    Fusion proteins of enveloped viruses categorized as class I are typified by two distinct heptad repeat domains within the transmembrane subunit. These repeats are important structural elements that assemble into the six-helix bundles characteristic of the fusion-activated envelope trimer. Peptides derived from these domains can be potent and specific inhibitors of membrane fusion and virus infection. To facilitate our understanding of retroviral entry, peptides corresponding to the two heptad repeat domains of the avian sarcoma and leukosis virus subgroup A (ASLV-A) TM subunit of the envelope protein were characterized. Two peptides corresponding to the C-terminal heptad repeat (HR2), offset from one another by three residues, were effective inhibitors of infection, while two overlapping peptides derived from the N-terminal heptad repeat (HR1) were not. Analysis of envelope mutants containing substitutions within the HR1 domain revealed that a single amino acid change, L62A, significantly reduced sensitivity to peptide inhibition. Virus bound to cells at 4 degrees C became sensitive to peptide within the first 5 min of elevating the temperature to 37 degrees C and lost sensitivity to peptide after 15 to 30 min, consistent with a transient intermediate in which the peptide binding site is exposed. In cell-cell fusion experiments, peptide inhibitor sensitivity occurred prior to a fusion-enhancing low-pH pulse. Soluble receptor for ASLV-A induces a lipophilic character in the envelope which can be measured by stable liposome binding, and this activation was found to be unaffected by inhibitory HR2 peptide. Finally, receptor-triggered conformational changes in the TM subunit were also found to be unaffected by inhibitory peptide. These changes are marked by a dramatic shift in mobility on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, from a subunit of 37 kDa to a complex of about 80 kDa. Biotinylated HR2 peptide bound specifically to the 80-kDa complex

  3. Cutaneous and diphtheritic avian poxvirus infection in a nestling Southern Giant Petrel (Macronectes giganteus) from Antarctica

    Science.gov (United States)

    Shearn-Bochsler, Valerie; Green, David Earl; Converse, K.A.; Docherty, D.E.; Thiel, T.; Geisz, H.N.; Fraser, William R.; Patterson-Fraser, Donna L.

    2008-01-01

    The Southern giant petrel (Macronectes giganteus) is declining over much of its range and currently is listed as vulnerable to extinction by the International Union for the Conservation of Nature (IUCN). Island-specific breeding colonies near Palmer Station, Antarctica, have been monitored for over 30 years, and because this population continues to increase, it is critically important to conservation. In austral summer 2004, six diseased giant petrel chicks were observed in four of these colonies. Diseased chicks were 6a??9 weeks old and had multiple proliferative nodules on their bills and skin. One severely affected chick was found dead on the nest and was salvaged for necropsy. Histopathological examination of nodules from the dead chick revealed epithelial cell hyperplasia and hypertrophy with numerous eosinophilic intracytoplasmic inclusions (B??llinger bodies). A poxvirus was isolated from multiple nodules. Poxviral infection has not been reported in this species, and the reason for its emergence and its potential impact on the population are not yet known.

  4. Climate-driven spatial dynamics of plague among prairie dog colonies.

    Science.gov (United States)

    Snäll, T; O'Hara, R B; Ray, C; Collinge, S K

    2008-02-01

    We present a Bayesian hierarchical model for the joint spatial dynamics of a host-parasite system. The model was fitted to long-term data on regional plague dynamics and metapopulation dynamics of the black-tailed prairie dog, a declining keystone species of North American prairies. The rate of plague transmission between colonies increases with increasing precipitation, while the rate of infection from unknown sources decreases in response to hot weather. The mean annual dispersal distance of plague is about 10 km, and topographic relief reduces the transmission rate. Larger colonies are more likely to become infected, but colony area does not affect the infectiousness of colonies. The results suggest that prairie dog movements do not drive the spread of plague through the landscape. Instead, prairie dogs are useful sentinels of plague epizootics. Simulations suggest that this model can be used for predicting long-term colony and plague dynamics as well as for identifying which colonies are most likely to become infected in a specific year.

  5. Differentially expressed genes in a flock of Chinese local-breed chickens infected with a subgroup J avian leukosis virus using suppression subtractive hybridization.

    Science.gov (United States)

    Zhao, Guiping; Zheng, Maiqing; Chen, Jilan; Wen, Jie; Wu, Chunmei; Li, Wenjuan; Liu, Libo; Zhang, Yuan

    2010-01-01

    Avian leukosis virus subgroup J (ALV-J) is a new type of virus that mainly induces myeloid leukosis (ML) in chickens. To further elucidate the pathogenesis of ALV-J infection and tumor development, expression profiles from the bone marrow tissue of 15 infected and 18 non-infected birds from a local-breed poultry-farm under naturally infected conditions, were analyzed by suppression-subtractive hybridization. The birds were diagnosed as ML+ (or ML-) by specific ALV-J detection methods, involving serological tests for antigens and antibodies, and RT-PCR to detect viral RNA. A total of 59 partial gene sequences were revealed by differential screening of 496 forward and 384 reverse subtracted cDNA clones. Of these, 22 identified genes, including 8 up-regulated and 14 down-regulated, were related to immune functions, these genes being, MHC B-G antigen, translationally-controlled tumor protein (TPT1/TPTC), transferrin and ferritin, hemoglobin and Carbonic anhydrase. Four of the down-regulated genes were selected for further analysis, in view of their predicted roles in infection and immunity by real-time qRT-PCR, using RNA collected from the same birds as those used for SSH. The four genes were expressed at significantly lower levels (p < 0.001) in ALV-J infected birds than in non-infected ones.

  6. Differentially expressed genes in a flock of Chinese local-breed chickens infected with a subgroup J avian leukosis virus using suppression subtractive hybridization

    Directory of Open Access Journals (Sweden)

    Guiping Zhao

    2010-01-01

    Full Text Available Avian leukosis virus subgroup J (ALV-J is a new type of virus that mainly induces myeloid leukosis (ML in chickens. To further elucidate the pathogenesis of ALV-J infection and tumor development, expression profiles from the bone marrow tissue of 15 infected and 18 non-infected birds from a local-breed poultry-farm under naturally infected conditions, were analyzed by suppression-subtractive hybridization. The birds were diagnosed as ML+ (or ML- by specific ALV-J detection methods, involving serological tests for antigens and antibodies, and RT-PCR to detect viral RNA. A total of 59 partial gene sequences were revealed by differential screening of 496 forward and 384 reverse subtracted cDNA clones. Of these, 22 identified genes, including 8 up-regulated and 14 down-regulated, were related to immune functions, these genes being, MHC B-G antigen, translationally-controlled tumor protein (TPT1/TPTC, transferrin and ferritin, hemoglobin and Carbonic anhydrase. Four of the down-regulated genes were selected for further analysis, in view of their predicted roles in infection and immunity by real-time qRT-PCR, using RNA collected from the same birds as those used for SSH. The four genes were expressed at significantly lower levels (p < 0.001 in ALV-J infected birds than in non-infected ones.

  7. The critical time of avian leukosis virus subgroup J-mediated immunosuppression during early stage infection in specific pathogen-free chickens.

    Science.gov (United States)

    Wang, Feng; Wang, Xiaowei; Chen, Hongbo; Liu, Jianzhu; Cheng, Ziqiang

    2011-09-01

    The critical time of avian leukosis virus subgroup J (ALV-J)-mediated immunosuppression was determined by body weight, relative immune organ weight, histopathology, and presence of group specific antigen and antibodies in specific pathogen-free (SPF) chickens. CD4(+) and CD8(+) cell activity in the spleen, total and differential leukocyte counts in blood, and viral RNA levels in spleen were measured. Significant growth suppression was observed in the two ALV-J-infected groups. A strong immune response by infected groups was present in spleen at 2-weeks-of-age, but after 4-weeks-of-age, the response decreased quickly. The thymus and bursa showed persistent immunosuppression until 4-weeks-of-age. Proliferation of fibroblasts and dendritic cells were observed in immune organs at 4- and 5-weeks-of-age. However, the granulocyte cell number was markedly lower in the infected groups than in the control group. In group 1 (day 1 infection) CD4(+) cells increased during the second week but significantly decreased during the fourth week, while group 2 (day 7 infection) showed the opposite effect. Viral RNA increased significantly by the fourth week. These data identify 3~4 weeks post-infection as the key time at which the ALV-J virus exerts its immunosuppressive effects on the host.

  8. Colorado animal-based plague surveillance systems: relationships between targeted animal species and prediction efficacy of areas at risk for humans.

    Science.gov (United States)

    Lowell, Jennifer L; Eisen, Rebecca J; Schotthoefer, Anna M; Xiaocheng, Liang; Montenieri, John A; Tanda, Dale; Pape, John; Schriefer, Martin E; Antolin, Michael F; Gage, Kenneth L

    2009-06-01

    Human plague risks (Yersinia pestis infection) are greatest when epizootics cause high mortality among this bacterium's natural rodent hosts. Therefore, health departments in plague-endemic areas commonly establish animal-based surveillance programs to monitor Y. pestis infection among plague hosts and vectors. The primary objectives of our study were to determine whether passive animal-based plague surveillance samples collected in Colorado from 1991 to 2005 were sampled from high human plague risk areas and whether these samples provided information useful for predicting human plague case locations. By comparing locations of plague-positive animal samples with a previously constructed GIS-based plague risk model, we determined that the majority of plague-positive Gunnison's prairie dogs (100%) and non-prairie dog sciurids (85.82%), and moderately high percentages of sigmodontine rodents (71.4%), domestic cats (69.3%), coyotes (62.9%), and domestic dogs (62.5%) were recovered within 1 km of the nearest area posing high peridomestic risk to humans. In contrast, the majority of white-tailed prairie dog (66.7%), leporid (cottontailed and jack rabbits) (71.4%), and black-tailed prairie dog (93.0%) samples originated more than 1 km from the nearest human risk habitat. Plague-positive animals or their fleas were rarely (one of 19 cases) collected within 2 km of a case exposure site during the 24 months preceding the dates of illness onset for these cases. Low spatial accuracy for identifying epizootic activity prior to human plague cases suggested that other mammalian species or their fleas are likely more important sources of human infection in high plague risk areas. To address this issue, epidemiological observations and multi-locus variable number tandem repeat analyses (MLVA) were used to preliminarily identify chipmunks as an under-sampled, but potentially important, species for human plague risk in Colorado.

  9. Flea abundance on black-tailed prairie dogs (Cynomys ludovicianus) increases during plague epizootics.

    Science.gov (United States)

    Tripp, Daniel W; Gage, Kenneth L; Montenieri, John A; Antolin, Michael F

    2009-06-01

    Black-tailed prairie dogs (Cynomys ludovicianus) on the Great Plains of the United States are highly susceptible to plague, caused by the bacterium Yersinia pestis, with mortality on towns during plague epizootics often approaching 100%. The ability of flea-borne transmission to sustain disease spread has been questioned because of inefficiency of flea vectors. However, even with low individual efficiency, overall transmission can be increased if flea abundance (the number of fleas on hosts) increases. Changes in flea abundance on hosts during plague outbreaks were recorded during a large-scale study of plague outbreaks in prairie dogs in north central Colorado during 3 years (2004-2007). Fleas were collected from live-trapped black-tailed prairie dogs before and during plague epizootics and tested by PCR for the presence of Y. pestis. The predominant fleas were two prairie dog specialists (Oropsylla hirsuta and Oropsylla tuberculata cynomuris), and a generalist flea species (Pulex simulans) was also recorded from numerous mammals in the area. The three species differ in seasonal abundance, with greatest abundance in spring (February and March) and fall (September and October). Flea abundance and infestation intensity increased during epizootics and were highest on prairie dogs with Y. pestis-infected fleas. Seasonal occurrence of epizootics among black-tailed prairie dogs was found to coincide with seasonal peaks in flea abundance. Concentration of infected fleas on surviving animals may account for rapid spread of plague during epizootics. In particular, the role of the generalist flea P. simulans was previously underappreciated.

  10. Previous infection with virulent strains of Newcastle disease virus reduces highly pathogenic avian influenza virus replication, disease, and mortality in chickens.

    Science.gov (United States)

    Costa-Hurtado, Mar; Afonso, Claudio L; Miller, Patti J; Shepherd, Eric; Cha, Ra Mi; Smith, Diane; Spackman, Erica; Kapczynski, Darrell R; Suarez, David L; Swayne, David E; Pantin-Jackwood, Mary J

    2015-09-23

    Highly pathogenic avian influenza virus (HPAIV) and Newcastle disease virus (NDV) are two of the most important viruses affecting poultry worldwide and produce co-infections especially in areas of the world where both viruses are endemic; but little is known about the interactions between these two viruses. The objective of this study was to determine if co-infection with NDV affects HPAIV replication in chickens. Only infections with virulent NDV strains (mesogenic Pigeon/1984 or velogenic CA/2002), and not a lentogenic NDV strain (LaSota), interfered with the replication of HPAIV A/chicken/Queretaro/14588-19/95 (H5N2) when the H5N2 was given at a high dose (10(6.9) EID50) two days after the NDV inoculation, but despite this interference, mortality was still observed. However, chickens infected with the less virulent mesogenic NDV Pigeon/1984 strain three days prior to being infected with a lower dose (10(5.3-5.5) EID50) of the same or a different HPAIV, A/chicken/Jalisco/CPA-12283-12/2012 (H7N3), had reduced HPAIV replication and increased survival rates. In conclusion, previous infection of chickens with virulent NDV strains can reduce HPAIV replication, and consequently disease and mortality. This interference depends on the titer of the viruses used, the virulence of the NDV, and the timing of the infections. The information obtained from these studies helps to understand the possible interactions and outcomes of infection (disease and virus shedding) when HPAIV and NDV co-infect chickens in the field.

  11. Plague dynamics are driven by climate variation

    DEFF Research Database (Denmark)

    Stenseth, Nils Chr.; Samia, Noelle I.; Viljugrein, Hildegunn

    2006-01-01

    The bacterium Yersinia pestis causes bubonic plague. In Central Asia, where human plague is still reported regularly, the bacterium is common in natural populations of great gerbils. By using field data from 1949-1995 and previously undescribed statistical techniques, we show that Y. pestis...... prevalence in gerbils increases with warmer springs and wetter summers: A 1°C increase in spring is predicted to lead to a >50% increase in prevalence. Climatic conditions favoring plague apparently existed in this region at the onset of the Black Death as well as when the most recent plague pandemic arose...... in the same region, and they are expected to  continue or become more favorable as a result of climate change.  Threats of outbreaks may thus be increasing where humans live in close contact with rodents and fleas (or other wildlife) harboring endemic plague....

  12. Distribution of avian influenza H5N1 viral RNA in tissues of AI-vaccinated and unvaccinated contact chickens after experimental infection.

    Science.gov (United States)

    Hassan, Mohamed K; Kilany, Walid H; Abdelwhab, E M; Arafa, Abdel-Satar; Selim, Abdullah; Samy, Ahmed; Samir, M; Le Brun, Yvon; Jobre, Yilma; Aly, Mona M

    2012-05-01

    Avian influenza due to highly pathogenic avian influenza (HPAIV) H5N1 virus is not a food-borne illness but a serious panzootic disease with the potential to be pandemic. In this study, broiler chickens were vaccinated with commercial H5N1 or H5N2 inactivated vaccines prior to being challenged with an HPAIV H5N1 (clade 2.2.1 classic) virus. Challenged and non-challenged vaccinated chickens were kept together, and unvaccinated chickens served as contact groups. Post-challenge samples from skin and edible internal organs were collected from dead and sacrificed (after a 14-day observation period) birds and tested using qRT-PCR for virus detection and quantification. H5N1 vaccine protected chickens against morbidity, mortality and transmission. Virus RNA was not detected in the meat or edible organs of chickens vaccinated with H5N1 vaccine. Conversely, H5N2 vaccine did not confer clinical protection, and a significant virus load was detected in the meat and internal organs. Phylogenetic analysis showed that the H5N1 virus vaccine and challenge virus strains are closely related. The results of the present study strongly suggest a need for proper selection of vaccines and their routine evaluation against newly emergent field viruses. These actions will help to reduce human exposure to HPAIV H5N1 virus from both infected live birds and slaughtered poultry. In addition, rigorous preventive measures should be put in place in order to minimize the public-health risks of avian influenza at the human-animal interface.

  13. Avian Wings

    Science.gov (United States)

    Liu, Tianshu; Kuykendoll, K.; Rhew, R.; Jones, S.

    2004-01-01

    This paper describes the avian wing geometry (Seagull, Merganser, Teal and Owl) extracted from non-contact surface measurements using a three-dimensional laser scanner. The geometric quantities, including the camber line and thickness distribution of airfoil, wing planform, chord distribution, and twist distribution, are given in convenient analytical expressions. Thus, the avian wing surfaces can be generated and the wing kinematics can be simulated. The aerodynamic characteristics of avian airfoils in steady inviscid flows are briefly discussed. The avian wing kinematics is recovered from videos of three level-flying birds (Crane, Seagull and Goose) based on a two-jointed arm model. A flapping seagull wing in the 3D physical space is re-constructed from the extracted wing geometry and kinematics.

  14. Avian influenza

    Science.gov (United States)

    ... of avian influenza A in Asia, Africa, Europe, Indonesia, Vietnam, the Pacific, and the near East. Hundreds ... to detect abnormal breath sounds) Chest x-ray Culture from the nose or throat A method or ...

  15. Avian Influenza

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a letter from a professor at Clemson University about waterfowl that had been tested for avian influenza at Santee National Wildlife Refuge

  16. Experimental infection of mandarin duck with highly pathogenic avian influenza A (H5N8 and H5N1) viruses.

    Science.gov (United States)

    Kang, Hyun-Mi; Lee, Eun-Kyoung; Song, Byung-Min; Heo, Gyeong-Beom; Jung, Joojin; Jang, Il; Bae, You-Chan; Jung, Suk Chan; Lee, Youn-Jeong

    2017-01-01

    A highly pathogenic avian influenza (HPAI) H5N8 virus was first detected in poultry and wild birds in South Korea in January 2014. Here, we determined the pathogenicity and transmissibility of three different clades of H5 viruses in mandarin ducks to examine the potential for wild bird infection. H5N8 (clade 2.3.4.4) replicated more efficiently in the upper and lower respiratory tract of mandarin ducks than two previously identified H5N1 virus clades (clades 2.2 and 2.3.2.1). However, none of the mandarin ducks infected with H5N8 and H5N1 viruses showed severe clinical signs or mortality, and gross lesions were only observed in a few tissues. Viral replication and shedding were greater in H5N8-infected ducks than in H5N1-infected ducks. Recovery of all viruses from control duck in contact with infected ducks indicated that the highly pathogenic H5 viruses spread horizontally through contact. Taken together, these results suggest that H5N8 viruses spread efficiently in mandarin ducks. Further studies of pathogenicity in wild birds are required to examine possible long-distance dissemination via migration routes.

  17. Role of gga-miR-221 and gga-miR-222 during Tumour Formation in Chickens Infected by Subgroup J Avian Leukosis Virus

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    Zhenkai Dai

    2015-12-01

    Full Text Available Subgroup J avian leukosis virus (ALV-J causes a neoplastic disease in infected chickens. Differential expression patterns of microRNAs (miRNAs are closely related to the formation and growth of tumors. (1 Background: This study was undertaken to understand how miRNAs might be related to tumor growth during ALV-J infection. We chose to characterize the effects of miR-221 and miR-222 on cell proliferation, migration, and apoptosis based on previous microarray data. (2 Methods: In vivo, the expression levels of miR-221 and miR-222 were significantly increased in the liver of ALV-J infected chickens (p < 0.01. Over-expression of gga-miR-221 and gga-miR-222 promoted the proliferation, migration, and growth of DF-1 cells, and decreased the expression of BCL-2 modifying factor (BMF making cells more resistant to apoptosis. (3 Results: Our results suggest that gga-miR-221 and gga-miR-222 may be tumour formation relevant gene in chicken that promote proliferation, migration, and growth of cancer cells, and inhibit apoptosis. BMF expression was significantly reduced in vivo 70 days after ALV-J infection. They may also play a pivotal role in tumorigenesis during ALV-J infection.

  18. Role of gga-miR-221 and gga-miR-222 during Tumour Formation in Chickens Infected by Subgroup J Avian Leukosis Virus.

    Science.gov (United States)

    Dai, Zhenkai; Ji, Jun; Yan, Yiming; Lin, Wencheng; Li, Hongxin; Chen, Feng; Liu, Yang; Chen, Weiguo; Bi, Yingzuo; Xie, Qingmei

    2015-12-11

    Subgroup J avian leukosis virus (ALV-J) causes a neoplastic disease in infected chickens. Differential expression patterns of microRNAs (miRNAs) are closely related to the formation and growth of tumors. (1) BACKGROUND: This study was undertaken to understand how miRNAs might be related to tumor growth during ALV-J infection. We chose to characterize the effects of miR-221 and miR-222 on cell proliferation, migration, and apoptosis based on previous microarray data. (2) METHODS: In vivo, the expression levels of miR-221 and miR-222 were significantly increased in the liver of ALV-J infected chickens (p < 0.01). Over-expression of gga-miR-221 and gga-miR-222 promoted the proliferation, migration, and growth of DF-1 cells, and decreased the expression of BCL-2 modifying factor (BMF) making cells more resistant to apoptosis. (3) RESULTS: Our results suggest that gga-miR-221 and gga-miR-222 may be tumour formation relevant gene in chicken that promote proliferation, migration, and growth of cancer cells, and inhibit apoptosis. BMF expression was significantly reduced in vivo 70 days after ALV-J infection. They may also play a pivotal role in tumorigenesis during ALV-J infection.

  19. Infection of chicken bone marrow mononuclear cells with subgroup J avian leukosis virus inhibits dendritic cell differentiation and alters cytokine expression.

    Science.gov (United States)

    Liu, Di; Qiu, Qianqian; Zhang, Xu; Dai, Manman; Qin, Jianru; Hao, Jianjong; Liao, Ming; Cao, Weisheng

    2016-10-01

    Subgroup J avian leukosis virus (ALV-J) is an oncogenic retrovirus known to induce tumor formation and immunosuppression in infected chickens. One of the organs susceptible to ALV-J is the bone marrow, from which specialized antigen-presenting cells named dendritic cells (BM-DCs) are derived. Notably, these cells possess the unique ability to induce primary immune responses. In the present study, a method of cultivating and purifying DCs from chicken bone marrow in vitro was established to investigate the effects of ALV-J infection on BM-DC differentiation or generation. The results indicated that ALV-J not only infects the chicken bone marrow mononuclear cells but also appears to inhibit the differentiation and maturation of BM-DCs and to trigger apoptosis. Moreover, substantial reductions in the mRNA expression of TLR1, TLR2, TLR3, MHCI, and MHCII and in cytokine production were detected in the surviving BM-DCs following ALV-J infection. These findings indicate that ALV-J infection disrupts the process of bone marrow mononuclear cell differentiation into BM-DCs likely via altered antigen presentation, resulting in a downstream immune response in affected chickens.

  20. Differences in the Epidemiology of Childhood Infections with Avian Influenza A H7N9 and H5N1 Viruses

    Science.gov (United States)

    Chen, Xiaowen; Zhao, Na; Luo, Mengyun; Dong, Yuanyuan

    2016-01-01

    The difference between childhood infections with avian influenza viruses A(H5N1) and A(H7N9) remains an unresolved but critically important question. We compared the epidemiological characteristics of 244 H5N1 and 41 H7N9 childhood cases (H7N9 childhood infections (31.1% vs. 6.4%, p = 0.000). However, the two groups did not differ significantly in age (median age: 5.0 vs. 5.5 y, p = 0.0651). The proportion of clustered cases was significantly greater among children infected with H5N1 than among children infected with H7N9 [46.7% (71/152) vs. 23.6% (13/55), p = 0.005], and most of the childhood cases were identified as secondary cases [46.4% (45/97) vs. 33.3% (10/30), p = 0.000]. Mild status accounted for 79.49% and 22.66%, severe status for 17.95% and 2.34%, and fatal cases for 2.56% and 75.00% of the H7N9 and H5N1 childhood infection cases (all pH7N9 childhood cluster cases were identified. In conclusion, lower severity and greater transmission were found in the H7N9 childhood cases than in the H5N1 childhood cases. PMID:27695069

  1. Avian hematology.

    Science.gov (United States)

    Jones, Michael P

    2015-01-01

    Avian veterinarians often rely heavily on the results of various diagnostic tests, including hematology results. As such, cellular identification and evaluation of the cellular response are invaluable tools that help veterinarians understand the health or condition of their patient, as well as to monitor severity and clinical progression of disease and response to treatment. Therefore, it is important to thoroughly understand how to identify and evaluate changes in the avian erythron and leukon, as well as to interpret normal and abnormal results.

  2. Avian Research

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    Aims and Scope Avian Research is an open access,peer-reviewed journal publishing high quality research and review articles on all aspects of ornithology from all over the world.It aims to report the latest and most significant progress in ornithology and to encourage exchange of ideas among international ornithologists.As an Open Access journal,Avian Research provides a unique opportunity to publish

  3. Avian Research

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    <正>Aims and Scope Avian Research is an open access,peer-reviewed journal publishing high quality research and review articles on all aspects of ornithology from all over the world.It aims to report the latest and most significant progress in ornithology and to encourage exchange of ideas among international ornithologists.As an Open Access journal,Avian Research provides a unique opportunity to publish high quality contents that will be internationally accessible to any reader at no cost.

  4. Avian Research

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Aims and Scope Avian Research is an open access,peer-reviewed journal publishing high quality research and review articles on all aspects of ornithology from all over the world.It aims to report the latest and most signi cant progress in ornithology and to encourage exchange of ideas among international ornithologists.As an Open Access journal,Avian Research provides a unique opportunity to publish

  5. Reduced experimental infectivity and transmissibility of intercontinental H5 (H5N8 and H5N2) compared to Eurasian H5N1 highly pathogenic avian influenza viruses for chickens, turkeys, and Japanese quail

    Science.gov (United States)

    H5N1 high pathogenicity avian influenza (HPAI) virus (HPAIV) emerged in 1996 in Guangdong China and has since spread to infect and cause deaths in wild birds, poultry and humans in over 63 countries in Asia, Europe and Africa; and more recently a reassortant H5N8 clade 2.3.4.4 HPAI virus has spread ...

  6. Gr1(+) Cells Control Growth of YopM-Negative Yersinia pestis during Systemic Plague

    NARCIS (Netherlands)

    Ye, Z.; Kerschen, E.J.; Cohen, D.; Kaplan, A.M.; Rooijen, van N.; Straley, S.C.

    2009-01-01

    YopM, a protein toxin of Yersinia pestis, is necessary for virulence in a mouse model of systemic plague. We previously reported YopM-dependent natural killer (NK) cell depletion from blood and spleen samples of infected mice. However, in this study we found that infection with Y. pestis KIM5 (YopM(

  7. Epidemiological analysis of the Eyam plague outbreak of 1665–1666

    Science.gov (United States)

    Whittles, Lilith K.

    2016-01-01

    Plague, caused by the bacterium Yersinia pestis, is one of the deadliest infectious diseases in human history, and still causes worrying outbreaks in Africa and South America. Despite the historical and current importance of plague, several questions remain unanswered concerning its transmission routes and infection risk factors. The plague outbreak that started in September 1665 in the Derbyshire village of Eyam claimed 257 lives over 14 months, wiping out entire families. Since previous attempts at modelling the Eyam plague, new data have been unearthed from parish records revealing a much more complete record of the disease. Using a stochastic compartmental model and Bayesian analytical methods, we found that both rodent-to-human and human-to-human transmission played an important role in spreading the infection, and that they accounted, respectively, for a quarter and three-quarters of all infections, with a statistically significant seasonality effect. We also found that the force of infection was stronger for infectious individuals living in the same household compared with the rest of the village. Poverty significantly increased the risk of disease, whereas adulthood decreased the risk. These results on the Eyam outbreak contribute to the current debate on the relative importance of plague transmission routes. PMID:27170724

  8. Prior infection of chickens with H1N1 or H1N2 avian influenza elicits partial heterologous protection against highly pathogenic H5N1.

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    Charles Nfon

    Full Text Available There is a critical need to have vaccines that can protect against emerging pandemic influenza viruses. Commonly used influenza vaccines are killed whole virus that protect against homologous and not heterologous virus. Using chickens we have explored the possibility of using live low pathogenic avian influenza (LPAI A/goose/AB/223/2005 H1N1 or A/WBS/MB/325/2006 H1N2 to induce immunity against heterologous highly pathogenic avian influenza (HPAI A/chicken/Vietnam/14/2005 H5N1. H1N1 and H1N2 replicated in chickens but did not cause clinical disease. Following infection, chickens developed nucleoprotein and H1 specific antibodies, and reduced H5N1 plaque size in vitro in the absence of H5 neutralizing antibodies at 21 days post infection (DPI. In addition, heterologous cell mediated immunity (CMI was demonstrated by antigen-specific proliferation and IFN-γ secretion in PBMCs re-stimulated with H5N1 antigen. Following H5N1 challenge of both pre-infected and naïve controls chickens housed together, all naïve chickens developed acute disease and died while H1N1 or H1N2 pre-infected chickens had reduced clinical disease and 70-80% survived. H1N1 or H1N2 pre-infected chickens were also challenged with H5N1 and naïve chickens placed in the same room one day later. All pre-infected birds were protected from H5N1 challenge but shed infectious virus to naïve contact chickens. However, disease onset, severity and mortality was reduced and delayed in the naïve contacts compared to directly inoculated naïve controls. These results indicate that prior infection with LPAI virus can generate heterologous protection against HPAI H5N1 in the absence of specific H5 antibody.

  9. Prior infection of chickens with H1N1 or H1N2 avian influenza elicits partial heterologous protection against highly pathogenic H5N1.

    Science.gov (United States)

    Nfon, Charles; Berhane, Yohannes; Pasick, John; Embury-Hyatt, Carissa; Kobinger, Gary; Kobasa, Darwyn; Babiuk, Shawn

    2012-01-01

    There is a critical need to have vaccines that can protect against emerging pandemic influenza viruses. Commonly used influenza vaccines are killed whole virus that protect against homologous and not heterologous virus. Using chickens we have explored the possibility of using live low pathogenic avian influenza (LPAI) A/goose/AB/223/2005 H1N1 or A/WBS/MB/325/2006 H1N2 to induce immunity against heterologous highly pathogenic avian influenza (HPAI) A/chicken/Vietnam/14/2005 H5N1. H1N1 and H1N2 replicated in chickens but did not cause clinical disease. Following infection, chickens developed nucleoprotein and H1 specific antibodies, and reduced H5N1 plaque size in vitro in the absence of H5 neutralizing antibodies at 21 days post infection (DPI). In addition, heterologous cell mediated immunity (CMI) was demonstrated by antigen-specific proliferation and IFN-γ secretion in PBMCs re-stimulated with H5N1 antigen. Following H5N1 challenge of both pre-infected and naïve controls chickens housed together, all naïve chickens developed acute disease and died while H1N1 or H1N2 pre-infected chickens had reduced clinical disease and 70-80% survived. H1N1 or H1N2 pre-infected chickens were also challenged with H5N1 and naïve chickens placed in the same room one day later. All pre-infected birds were protected from H5N1 challenge but shed infectious virus to naïve contact chickens. However, disease onset, severity and mortality was reduced and delayed in the naïve contacts compared to directly inoculated naïve controls. These results indicate that prior infection with LPAI virus can generate heterologous protection against HPAI H5N1 in the absence of specific H5 antibody.

  10. Viral proliferation and expression of tumor-related gene in different chicken embryo fibroblasts infected with different tumorigenic phenotypes of avian leukosis virus subgroup J.

    Science.gov (United States)

    Qu, Yajin; Liu, Litao; Niu, Yujuan; Qu, Yue; Li, Ning; Sun, Wei; Lv, Chuanwei; Wang, Pengfei; Zhang, Guihua; Liu, Sidang

    2016-10-01

    Subgroup J avian leukosis virus (ALV-J) causes a neoplastic disease in infected chickens. The ALV-J strain NX0101, which was isolated from broiler breeders in 2001, mainly induced formation of myeloid cell tumors. However, strain HN10PY01, which was recently isolated from laying hens, mainly induces formation of myeloid cell tumors and hemangioma. To identify the molecular pathological mechanism underlying changes in host susceptibility and tumor classification induced by these two types of ALV-J strains, chicken embryo fibroblasts derived from chickens with different genetic backgrounds (broiler breeders and laying hens) and an immortalized chicken embryo fibroblasts (DF-1) were prepared and infected with strain NX0101 or HN10PY01, respectively. The 50% tissue culture infective dose (TCID50) and levels of ALV group-specific antigen p27 and heat shock protein 70 in the supernatant collected from the ALV-J infected cells were detected. Moreover, mRNA expression levels of tumor-related genes p53, c-myc, and Bcl-2 in ALV-J-infected cells were quantified. The results indicated that the infection of ALV-J could significantly increase mRNA expression levels of p53, c-myc, and Bcl-2 Strain HN10PY01 exhibited a greater influence on the three tumor-related genes in each of the three types of cells when compared with strain NX0101, and the TCID50 and p27 levels in the supernatant collected from HN10PY01-infected cells were higher than those collected from NX0101-infected cells. These results indicate that the infection of the two ALV-J strains influenced the gene expression levels in the infected cells, while the newly isolated strain HN10PY01 showed higher replication ability in cells and induced higher expression levels of tumor-related genes in infected cells. Furthermore, virus titers and expression levels of tumor-related genes and cellular stress responses of cells with different genetic backgrounds when infected with each of the two ALV-J strain were different

  11. Multivalent HA DNA vaccination protects against highly pathogenic H5N1 avian influenza infection in chickens and mice.

    Directory of Open Access Journals (Sweden)

    Srinivas Rao

    Full Text Available BACKGROUND: Sustained outbreaks of highly pathogenic avian influenza (HPAI H5N1 in avian species increase the risk of reassortment and adaptation to humans. The ability to contain its spread in chickens would reduce this threat and help maintain the capacity for egg-based vaccine production. While vaccines offer the potential to control avian disease, a major concern of current vaccines is their potency and inability to protect against evolving avian influenza viruses. METHODOLOGY / PRINCIPAL FINDINGS: The ability of DNA vaccines encoding hemagglutinin (HA proteins from different HPAI H5N1 serotypes was evaluated for its ability to elicit neutralizing antibodies and to protect against homologous and heterologous HPAI H5N1 strain challenge in mice and chickens after DNA immunization by needle and syringe or with a pressure injection device. These vaccines elicited antibodies that neutralized multiple strains of HPAI H5N1 when given in combinations containing up to 10 HAs. The response was dose-dependent, and breadth was determined by the choice of the influenza virus HA in the vaccine. Monovalent and trivalent HA vaccines were tested first in mice and conferred protection against lethal H5N1 A/Vietnam/1203/2004 challenge 68 weeks after vaccination. In chickens, protection was observed against heterologous strains of HPAI H5N1 after vaccination with a trivalent H5 serotype DNA vaccine with doses as low as 5 microg DNA given twice either by intramuscular needle injection or with a needle-free device. CONCLUSIONS/SIGNIFICANCE: DNA vaccines offer a generic approach to influenza virus immunization applicable to multiple animal species. In addition, the ability to substitute plasmids encoding different strains enables rapid adaptation of the vaccine to newly evolving field isolates.

  12. Modeling the epidemiological history of plague in Central Asia: Palaeoclimatic forcing on a disease system over the past millennium

    Directory of Open Access Journals (Sweden)

    Kausrud Kyrre

    2010-08-01

    Full Text Available Abstract Background Human cases of plague (Yersinia pestis infection originate, ultimately, in the bacterium's wildlife host populations. The epidemiological dynamics of the wildlife reservoir therefore determine the abundance, distribution and evolution of the pathogen, which in turn shape the frequency, distribution and virulence of human cases. Earlier studies have shown clear evidence of climatic forcing on contemporary plague abundance in rodents and humans. Results We find that high-resolution palaeoclimatic indices correlate with plague prevalence and population density in a major plague host species, the great gerbil (Rhombomys opimus, over 1949-1995. Climate-driven models trained on these data predict independent data on human plague cases in early 20th-century Kazakhstan from 1904-1948, suggesting a consistent impact of climate on large-scale wildlife reservoir dynamics influencing human epidemics. Extending the models further back in time, we also find correspondence between their predictions and qualitative records of plague epidemics over the past 1500 years. Conclusions Central Asian climate fluctuations appear to have had significant influences on regional human plague frequency in the first part of the 20th century, and probably over the past 1500 years. This first attempt at ecoepidemiological reconstruction of historical disease activity may shed some light on how long-term plague epidemiology interacts with human activity. As plague activity in Central Asia seems to have followed climate fluctuations over the past centuries, we may expect global warming to have an impact upon future plague epidemiology, probably sustaining or increasing plague activity in the region, at least in the rodent reservoirs, in the coming decades. See commentary: http://www.biomedcentral.com/1741-7007/8/108

  13. 人感染高致病性禽流感的流行与预防%Epidemic and prevention of human infections with highly pathogenic avian influenza

    Institute of Scientific and Technical Information of China (English)

    李刚

    2010-01-01

    @@ 人感染高致病性禽流行性感冒(human infections with highly pathogenic avian influenza)简称人禽流感,是指人感染甲型禽流感病毒(avian influenza virus,AIV)某些亚型的毒株引起的急性呼吸道传染病.1997年5月,我国香港特别行政区1例3岁儿童死于不明原因的多脏器功能哀竭,同年8月经美国疾病预防和摔制中心以及世界卫牛组织(WHO)荷兰鹿特丹国家流感中心鉴定为禽甲型流感病毒H5N1引起的人类流感,这是世界上首次证实禽甲型流感病毒H5N1感染人类.

  14. Comprehensive mapping of common immunodominant epitopes in the West Nile virus nonstructural protein 1 recognized by avian antibody responses.

    Directory of Open Access Journals (Sweden)

    Encheng Sun

    Full Text Available West Nile virus (WNV is a mosquito-borne flavivirus that primarily infects birds but occasionally infects humans and horses. Certain species of birds, including crows, house sparrows, geese, blue jays and ravens, are considered highly susceptible hosts to WNV. The nonstructural protein 1 (NS1 of WNV can elicit protective immune responses, including NS1-reactive antibodies, during infection of animals. The antigenicity of NS1 suggests that NS1-reactive antibodies could provide a basis for serological diagnostic reagents. To further define serological reagents for diagnostic use, the antigenic sites in NS1 that are targeted by host immune responses need to be identified and the potential diagnostic value of individual antigenic sites also needs to be defined. The present study describes comprehensive mapping of common immunodominant linear B-cell epitopes in the WNV NS1 using avian WNV NS1 antisera. We screened antisera from chickens, ducks and geese immunized with purified NS1 for reactivity against 35 partially overlapping peptides covering the entire WNV NS1. This study identified twelve, nine and six peptide epitopes recognized by chicken, duck and goose antibody responses, respectively. Three epitopes (NS1-3, 14 and 24 were recognized by antibodies elicited by immunization in all three avian species tested. We also found that NS1-3 and 24 were WNV-specific epitopes, whereas the NS1-14 epitope was conserved among the Japanese encephalitis virus (JEV serocomplex viruses based on the reactivity of avian WNV NS1 antisera against polypeptides derived from the NS1 sequences of viruses of the JEV serocomplex. Further analysis showed that the three common polypeptide epitopes were not recognized by antibodies in Avian Influenza Virus (AIV, Newcastle Disease Virus (NDV, Duck Plague Virus (DPV and Goose Parvovirus (GPV antisera. The knowledge and reagents generated in this study have potential applications in differential diagnostic approaches and

  15. Experimental infection of a North American raptor, American Kestrel (Falco sparverius), with highly pathogenic avian influenza virus (H5N1).

    Science.gov (United States)

    Hall, Jeffrey S; Ip, Hon S; Franson, J Christian; Meteyer, Carol; Nashold, Sean; TeSlaa, Joshua L; French, John; Redig, Patrick; Brand, Christopher

    2009-10-22

    Several species of wild raptors have been found in Eurasia infected with highly pathogenic avian influenza virus (HPAIV) subtype H5N1. Should HPAIV (H5N1) reach North America in migratory birds, species of raptors are at risk not only from environmental exposure, but also from consuming infected birds and carcasses. In this study we used American kestrels as a representative species of a North American raptor to examine the effects of HPAIV (H5N1) infection in terms of dose response, viral shedding, pathology, and survival. Our data showed that kestrels are highly susceptible to HPAIV (H5N1). All birds typically died or were euthanized due to severe neurologic disease within 4-5 days of inoculation and shed significant amounts of virus both orally and cloacally, regardless of dose administered. The most consistent microscopic lesions were necrosis in the brain and pancreas. This is the first experimental study of HPAIV infection in a North American raptor and highlights the potential risks to birds of prey if HPAIV (H5N1) is introduced into North America.

  16. Mutations in and Expression of the Tumor Suppressor Gene p53 in Egg-Type Chickens Infected With Subgroup J Avian Leukosis Virus.

    Science.gov (United States)

    Yue, Q; Yulong, G; Liting, Q; Shuai, Y; Delong, L; Yubao, L; Lili, J; Sidang, L; Xiaomei, W

    2015-11-01

    To investigate the molecular mechanisms of the oncogenic effects of avian leukosis virus subgroup J (ALV-J), we examined mutations in and the expression of p53 in the myelocytomas distributed in the liver, spleen, trachea, and bone marrow, as well as in fibrosarcomas in the abdominal cavity and hemangiomas in skin from chickens that were naturally or experimentally infected with ALV-J. Two types of mutations in the p53 gene were detected in myelocytomas of both the experimentally infected and the naturally infected chickens and included point mutations and deletions. Two of the point mutations have not been reported previously. Partial complementary DNA clones with a 122-bp deletion in the p53 gene ORF and a 15-bp deletion in the C-terminus were identified in the myelocytomas. In addition, moderate expression of the mutant p53 protein was detected in the myelocytomas that were distributed in the liver, trachea, spleen, and bone marrow. Mutant p53 protein was not detected in the subcutaneous hemangiomas or in the abdominal fibrosarcomas associated with natural and experimental ALV-J infection, respectively. These results identify mutations associated with abnormal expression of p53 in ALV-J-associated myelocytomas, suggesting a role in tumorigenesis.

  17. Experimental infection of a North American raptor, American Kestrel (Falco sparverius, with highly pathogenic avian influenza virus (H5N1.

    Directory of Open Access Journals (Sweden)

    Jeffrey S Hall

    Full Text Available Several species of wild raptors have been found in Eurasia infected with highly pathogenic avian influenza virus (HPAIV subtype H5N1. Should HPAIV (H5N1 reach North America in migratory birds, species of raptors are at risk not only from environmental exposure, but also from consuming infected birds and carcasses. In this study we used American kestrels as a representative species of a North American raptor to examine the effects of HPAIV (H5N1 infection in terms of dose response, viral shedding, pathology, and survival. Our data showed that kestrels are highly susceptible to HPAIV (H5N1. All birds typically died or were euthanized due to severe neurologic disease within 4-5 days of inoculation and shed significant amounts of virus both orally and cloacally, regardless of dose administered. The most consistent microscopic lesions were necrosis in the brain and pancreas. This is the first experimental study of HPAIV infection in a North American raptor and highlights the potential risks to birds of prey if HPAIV (H5N1 is introduced into North America.

  18. Experimental infection of a North American raptor, American kestrel (Falco sparverius), with highly pathogenic avian influenza virus (H5N1)

    Science.gov (United States)

    Hall, J.S.; Ip, H.S.; Franson, J.C.; Meteyer, C.; Nashold, S.; Teslaa, J.L.; French, J.; Redig, P.; Brand, C.

    2009-01-01

    Several species of wild raptors have been found in Eurasia infected with highly pathogenic avian influenza virus (HPAIV) subtype H5N1. Should HPAIV (H5N1) reach North America in migratory birds, species of raptors are at risk not only from environmental exposure, but also from consuming infected birds and carcasses. In this study we used American kestrels as a representative species of a North American raptor to examine the effects of HPAIV (H5N1) infection in terms of dose response, viral shedding, pathology, and survival. Our data showed that kestrels are highly susceptible to HPAIV (H5N1). All birds typically died or were euthanized due to severe neurologic disease within 4-5 days of inoculation and shed significant amounts of virus both orally and cloacally, regardless of dose administered. The most consistent microscopic lesions were necrosis in the brain and pancreas. This is the first experimental study of HPAIV infection in a North American raptor and highlights the potential risks to birds of prey if HPAIV (H5N1) is introduced into North America.

  19. Cell killing by avian leukosis viruses.

    OpenAIRE

    Weller, S K; Temin, H M

    1981-01-01

    Infection of chicken cells with a cytopathic avian leukosis virus resulted in the detachment of killed cells from the culture dish. The detached, dead cells contained more unintegrated viral DNA than the attached cells. These results confirm the hypothesis that cell killing after infection with a cytopathic avian leukosis virus is associated with accumulation of large amounts of unintegrated viral DNA. No accumulation of large amounts of integrated viral DNA was found in cells infected with c...

  20. Evaluation of the risk of neighbourhood infection of H7N1 Highly Pathogenic Avian Influenza in Italy using Q statistic.

    Science.gov (United States)

    Mulatti, Paolo; Kitron, Uriel; Jacquez, Geoffrey M; Mannelli, Alessandro; Marangon, Stefano

    2010-07-01

    Exposure to the risk of neighbourhood infection was estimated for the H7N1 Highly Pathogenic Avian Influenza (HPAI) epidemic that affected Northern Italy between 1999 and 2000. The two most affected regions (Lombardy and Veneto) were analyzed and the epidemic was divided into three phases. Q statistics were used to evaluate exposure to the risk of neighbourhood infection using two measures. First, a local Q statistic (Qikt) assessed daily exposure for each farm as a function of the number of neighbouring infected farms that were in their infectious period, weighted by the distance between farms. This allowed us to identify the daily time course of risk for each farm and, at any given time, local groups of farms defined by high risk. Second, for each farm a summary statistic of exposure risk within each phase (Qiph) was obtained by summing Qikt over the duration of each phase. This allowed identification of farms defined by persistent, high exposure risk within each phase of the epidemic. Statistical significance was evaluated using conditional Monte Carlo simulation, and significant values of Qiph were mapped to assess the variation of the risk of neighbourhood infection through the phases. Qikt was larger for farms in Lombardy and the reduction of exposed farms was more marked for Veneto. Although the highest value of Qiph was observed in Veneto, in each phase most of the significant values were in Lombardy. In the last phase of the epidemic, a large reduction in the number of farms significantly exposed to the risk of neighbourhood infection was observed in the Veneto region, along with generally low values of Qiph. This may be explained by differences in control measures in the two regions, including pre-emptive slaughtering of farms considered at high risk of infection. The Q statistic allowed us to quantify geographic, time-dynamic variations in exposure to neighbourhood infection, and to generate hypotheses on the efficacy of control measures.

  1. Avian influenza : a review article

    Directory of Open Access Journals (Sweden)

    A. Yalda

    2006-07-01

    Full Text Available The purpose of this paper is to provides general information about avian influenza (bird flu and specific information about one type of bird flu, called avian influenza A (H5N1, that has caused infections in birds in Asia and Europe and in human in Asia. The main materials in this report are based on the World Health Organization (WHO , world organization for animal health (OIE , food and agriculture organization of the united nations (FAO information and recommendations and review of the published literature about avian influenza. Since December 2003, highly pathogenic H5N1 avian influenza viruses have swept through poultry populations across Asia and parts of Europe. The outbreaks are historically unprecedented in scale and geographical spread. Their economic impact on the agricultural sector of the affected countries has been large. Human cases, with an overall fatality rate around 50%, have also been reported and almost all human infections can be linked to contact with infected poultry. Influenza viruses are genetically unstable and their behaviour cannot be predicted so the risk of further human cases persists. The human health implications have now gained importance, both for illness and fatalities that have occurred following natural infection with avian viruses, and for the potential of generating a re-assortant virus that could give rise to the next human influenza pandemic.

  2. Host cytokine responses of pigeons infected with highly pathogenic Thai avian influenza viruses of subtype H5N1 isolated from wild birds.

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    Tsuyoshi Hayashi

    Full Text Available Highly pathogenic avian influenza virus (HPAIV of the H5N1 subtype has been reported to infect pigeons asymptomatically or induce mild symptoms. However, host immune responses of pigeons inoculated with HPAIVs have not been well documented. To assess host responses of pigeons against HPAIV infection, we compared lethality, viral distribution and mRNA expression of immune related genes of pigeons infected with two HPAIVs (A/Pigeon/Thailand/VSMU-7-NPT/2004; Pigeon04 and A/Tree sparrow/Ratchaburi/VSMU-16-RBR/2005; T.sparrow05 isolated from wild birds in Thailand. The survival experiment showed that 25% of pigeons died within 2 weeks after the inoculation of two HPAIVs or medium only, suggesting that these viruses did not cause lethal infection in pigeons. Pigeon04 replicated in the lungs more efficiently than T.sparrow05 and spread to multiple extrapulmonary organs such as the brain, spleen, liver, kidney and rectum on days 2, 5 and 9 post infection. No severe lesion was observed in the lungs infected with Pigeon04 as well as T.sparrow05 throughout the collection periods. Encephalitis was occasionally observed in Pigeon04- or T.sparrow05-infected brain, the severity, however was mostly mild. To analyze the expression of immune-related genes in the infected pigeons, we established a quantitative real-time PCR analysis for 14 genes of pigeons. On day 2 post infection, Pigeon04 induced mRNA expression of Mx1, PKR and OAS to a greater extent than T.sparrow05 in the lungs, however their expressions were not up-regulated concomitantly on day 5 post infection when the peak viral replication was observed. Expressions of TLR3, IFNα, IL6, IL8 and CCL5 in the lungs following infection with the two HPAIVs were low. In sum, Pigeon04 exhibited efficient replication in the lungs compared to T.sparrow05, but did not induce excessive host cytokine expressions. Our study has provided the first insight into host immune responses of pigeons against HPAIV infection.

  3. Plague circulation and population genetics of the reservoir Rattus rattus: the influence of topographic relief on the distribution of the disease within the Madagascan focus.

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    Carine Brouat

    Full Text Available BACKGROUND: Landscape may affect the distribution of infectious diseases by influencing the population density and dispersal of hosts and vectors. Plague (Yersinia pestis infection is a highly virulent, re-emerging disease, the ecology of which has been scarcely studied in Africa. Human seroprevalence data for the major plague focus of Madagascar suggest that plague spreads heterogeneously across the landscape as a function of the relief. Plague is primarily a disease of rodents. We therefore investigated the relationship between disease distribution and the population genetic structure of the black rat, Rattus rattus, the main reservoir of plague in Madagascar. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a comparative study of plague seroprevalence and genetic structure (15 microsatellite markers in rat populations from four geographic areas differing in topology, each covering about 150-200 km(2 within the Madagascan plague focus. The seroprevalence levels in the rat populations mimicked those previously reported for humans. As expected, rat populations clearly displayed a more marked genetic structure with increasing relief. However, the relationship between seroprevalence data and genetic structure differs between areas, suggesting that plague distribution is not related everywhere to the effective dispersal of rats. CONCLUSIONS/SIGNIFICANCE: Genetic diversity estimates suggested that plague epizootics had only a weak impact on rat population sizes. In the highlands of Madagascar, plague dissemination cannot be accounted for solely by the effective dispersal of the reservoir. Human social activities may also be involved in spreading the disease in rat and human populations.

  4. Outbreak of Plague in a High Malaria Endemic Region - Nyimba District, Zambia, March-May 2015.

    Science.gov (United States)

    Sinyange, Nyambe; Kumar, Ramya; Inambao, Akatama; Moonde, Loveness; Chama, Jonathan; Banda, Mapopa; Tembo, Elliot; Nsonga, Beron; Mwaba, John; Fwoloshi, Sombo; Musokotwane, Kebby; Chizema, Elizabeth; Kapin'a, Muzala; Hang'ombe, Benard Mudenda; Baggett, Henry C; Hachaambwa, Lottie

    2016-08-12

    Outbreaks of plague have been recognized in Zambia since 1917 (1). On April 10, 2015, Zambia's Ministry of Health was notified by the Eastern Provincial Medical Office of possible bubonic plague cases in Nyimba District. Eleven patients with acute fever and cervical lymphadenopathy had been evaluated at two rural health centers during March 28-April 9, 2015; three patients died. To confirm the outbreak and develop control measures, the Zambia Ministry of Health's Field Epidemiology Training Program (ZFETP) conducted epidemiologic and laboratory investigations in partnership with the University of Zambia's schools of Medicine and Veterinary Medicine and the provincial and district medical offices. Twenty-one patients with clinically compatible plague were identified, with symptom onset during March 26-May 5, 2015. The median age was 8 years, and all patients were from the same village. Blood specimens or lymph node aspirates from six (29%) patients tested positive for Yersinia pestis by polymerase chain reaction (PCR). There is an urgent need to improve early identification and treatment of plague cases. PCR is a potential complementary tool for identifying plague, especially in areas with limited microbiologic capacity. Twelve (57%) patients, including all six with PCR-positive plague and all three who died, also tested positive for malaria by rapid diagnostic test (RDT). Plague patients coinfected with malaria might be misdiagnosed as solely having malaria, and appropriate antibacterial treatment to combat plague might not be given, increasing risk for mortality. Because patients with malaria might be coinfected with other pathogens, broad spectrum antibiotic treatment to cover other pathogens is recommended for all children with severe malaria, until a bacterial infection is excluded.

  5. Development of rapid immunochromatographic test for hemagglutinin antigen of H7 subtype in patients infected with novel avian influenza A (H7N9 virus.

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    Keren Kang

    Full Text Available BACKGROUND: Since human infection with the novel H7N9 avian influenza virus was identified in China in March 2013, the relatively high mortality rate and possibility of human-to-human transmission have highlighted the urgent need for sensitive and specific assays for diagnosis of H7N9 infection. METHODOLOGY/PRINCIPAL FINDINGS: We developed a rapid diagnostic test for the novel avian influenza A (H7N9 virus using anti-hemagglutinin (HA monoclonal antibodies specifically targeting H7 in an immunochromatographic assay system. The assay limit of detection was 103.5 pfu/ml or 103TCID50 of H7N9 virus. The assay specifically detected H7N9 viral isolates and recombinant HA proteins of H7 subtypes including H7N7 and H7N9, but did not react with non-H7 subtypes including H1N1, H3N2, H5N1, H5N9, and H9N2. The detection sensitivity was 59.4% (19/32 for H7N9 patients confirmed by RT-PCR. Moreover, the highest sensitivity of 61.5% (16/26 was obtained when testing H7N9 positive sputum samples while 35.7% (5/14 of nasopharyngeal swabs and 20% (2/10 of fecal samples tested positive. No false positive detection was found when testing 180 H7N9 negative samples. CONCLUSIONS/SIGNIFICANCE: Our novel rapid assay can specifically detect H7 HA antigen, facilitating rapid diagnosis for prevention and control of the on-going H7N9 epidemic.

  6. Activation of type I and III interferon signalling pathways occurs in lung epithelial cells infected with low pathogenic avian influenza viruses.

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    Richard Sutejo

    Full Text Available The host response to the low pathogenic avian influenza (LPAI H5N2, H5N3 and H9N2 viruses were examined in A549, MDCK, and CEF cells using a systems-based approach. The H5N2 and H5N3 viruses replicated efficiently in A549 and MDCK cells, while the H9N2 virus replicated least efficiently in these cell types. However, all LPAI viruses exhibited similar and higher replication efficiencies in CEF cells. A comparison of the host responses of these viruses and the H1N1/WSN virus and low passage pH1N1 clinical isolates was performed in A549 cells. The H9N2 and H5N2 virus subtypes exhibited a robust induction of Type I and Type III interferon (IFN expression, sustained STAT1 activation from between 3 and 6 hpi, which correlated with large increases in IFN-stimulated gene (ISG expression by 10 hpi. In contrast, cells infected with the pH1N1 or H1N1/WSN virus showed only small increases in Type III IFN signalling, low levels of ISG expression, and down-regulated expression of the IFN type I receptor. JNK activation and increased expression of the pro-apoptotic XAF1 protein was observed in A549 cells infected with all viruses except the H1N1/WSN virus, while MAPK p38 activation was only observed in cells infected with the pH1N1 and the H5 virus subtypes. No IFN expression and low ISG expression levels were generally observed in CEF cells infected with either AIV, while increased IFN and ISG expression was observed in response to the H1N1/WSN infection. These data suggest differences in the replication characteristics and antivirus signalling responses both among the different LPAI viruses, and between these viruses and the H1N1 viruses examined. These virus-specific differences in host cell signalling highlight the importance of examining the host response to avian influenza viruses that have not been extensively adapted to mammalian tissue culture.

  7. Global alert to avian influenza virus infection: from H5N1 to H7N9.

    Science.gov (United States)

    Poovorawan, Yong; Pyungporn, Sunchai; Prachayangprecha, Slinporn; Makkoch, Jarika

    2013-07-01

    Outbreak of a novel influenza virus is usually triggered by mutational change due to the process known as 'antigenic shift' or re-assortment process that allows animal-to-human or avian-to-human transmission. Birds are a natural reservoir for the influenza virus, and subtypes H5, H7, and H9 have all caused outbreaks of avian influenza in human populations. An especially notorious strain is the HPAI influenza virus H5N1, which has a mortality rate of approximately 60% and which has resulted in numerous hospitalizations, deaths, and significant economic loss. In March 2013, in Eastern China, there was an outbreak of the novel H7N9 influenza virus, which although less pathogenic in avian species, resulted in 131 confirmed cases and 36 deaths in humans over a two-month span. The rapid outbreak of this virus caused global concern but resulted in international cooperation to control the outbreak. Furthermore, cooperation led to valuable research-sharing including genome sequencing of the virus, the development of rapid and specific diagnosis, specimen sharing for future studies, and vaccine development. Although a H7N9 pandemic in the human population is possible due to its rapid transmissibility and extensive surveillance, the closure of the live-bird market will help mitigate the possibility of another H7N9 outbreak. In addition, further research into the source of the outbreak, pathogenicity of the virus, and the development of specific and sensitive detection assays will be essential for controlling and preparing for future H7N9 outbreaks.

  8. Sylvatic plague vaccine: combating plague in prarie dogs and black-footed ferrets

    Science.gov (United States)

    Rocke, Tonie E.; Abbott, Rachel C.

    2012-01-01

    After achieving promising results in laboratory trials, researchers at the USGS National Wildlife Health Center (NWHC) and University of Wisconsin at Madison will soon begin field testing a new oral vaccine for sylvatic plague, a devastating disease affecting prairie dogs and other mammals, particularly the endangered black-footed ferret. Our team has developed and is currently registering a sylvatic plague vaccine (SPV) that uses raccoon poxvirus (RCN) to express two key antigens of the Yersinia pestis bacterium, the causative agent of plague.

  9. Complete Protection against Pneumonic and Bubonic Plague after a Single Oral Vaccination.

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    Anne Derbise

    Full Text Available No efficient vaccine against plague is currently available. We previously showed that a genetically attenuated Yersinia pseudotuberculosis producing the Yersinia pestis F1 antigen was an efficient live oral vaccine against pneumonic plague. This candidate vaccine however failed to confer full protection against bubonic plague and did not produce F1 stably.The caf operon encoding F1 was inserted into the chromosome of a genetically attenuated Y. pseudotuberculosis, yielding the VTnF1 strain, which stably produced the F1 capsule. Given orally to mice, VTnF1 persisted two weeks in the mouse gut and induced a high humoral response targeting both F1 and other Y. pestis antigens. The strong cellular response elicited was directed mostly against targets other than F1, but also against F1. It involved cells with a Th1-Th17 effector profile, producing IFNγ, IL-17, and IL-10. A single oral dose (108 CFU of VTnF1 conferred 100% protection against pneumonic plague using a high-dose challenge (3,300 LD50 caused by the fully virulent Y. pestis CO92. Moreover, vaccination protected 100% of mice from bubonic plague caused by a challenge with 100 LD50 Y. pestis and 93% against a high-dose infection (10,000 LD50. Protection involved fast-acting mechanisms controlling Y. pestis spread out of the injection site, and the protection provided was long-lasting, with 93% and 50% of mice surviving bubonic and pneumonic plague respectively, six months after vaccination. Vaccinated mice also survived bubonic and pneumonic plague caused by a high-dose of non-encapsulated (F1- Y. pestis.VTnF1 is an easy-to-produce, genetically stable plague vaccine candidate, providing a highly efficient and long-lasting protection against both bubonic and pneumonic plague caused by wild type or un-encapsulated (F1-negative Y. pestis. To our knowledge, VTnF1 is the only plague vaccine ever reported that could provide high and durable protection against the two forms of plague after a single

  10. BIRD FLU (AVIAN INFLUENZA

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    Ali ACAR

    2005-12-01

    Full Text Available Avian influenza (bird flu is a contagious disease of animals caused by influenza A viruses. These flu viruses occur naturally among birds. Actually, humans are not infected by bird flu viruses.. However, during an outbreak of bird flu among poultry, there is a possible risk to people who have contact infect birds or surface that have been contaminated with excreations from infected birds. Symptoms of bird flu in humans have ranged from typical flu-like symptoms to eye infections, pneumonia, severe respiratory diseases and other severe and life-threatening complications. In such situation, people should avoid contact with infected birds or contaminated surface, and should be careful when handling and cooking poultry. [TAF Prev Med Bull 2005; 4(6.000: 345-353

  11. Highly pathogenic Avian Influenza A(H5N1) virus infection among workers at live bird markets, Bangladesh, 2009-2010.

    Science.gov (United States)

    Nasreen, Sharifa; Khan, Salah Uddin; Luby, Stephen P; Gurley, Emily S; Abedin, Jaynal; Zaman, Rashid Uz; Sohel, Badrul Munir; Rahman, Mustafizur; Hancock, Kathy; Levine, Min Z; Veguilla, Vic; Wang, David; Holiday, Crystal; Gillis, Eric; Sturm-Ramirez, Katharine; Bresee, Joseph S; Rahman, Mahmudur; Uyeki, Timothy M; Katz, Jacqueline M; Azziz-Baumgartner, Eduardo

    2015-04-01

    The risk for influenza A(H5N1) virus infection is unclear among poultry workers in countries where the virus is endemic. To assess H5N1 seroprevalence and seroconversion among workers at live bird markets (LBMs) in Bangladesh, we followed a cohort of workers from 12 LBMs with existing avian influenza surveillance. Serum samples from workers were tested for H5N1 antibodies at the end of the study or when LBM samples first had H5N1 virus-positive test results. Of 404 workers, 9 (2%) were seropositive at baseline. Of 284 workers who completed the study and were seronegative at baseline, 6 (2%) seroconverted (7 cases/100 poultry worker-years). Workers who frequently fed poultry, cleaned feces from pens, cleaned food/water containers, and did not wash hands after touching sick poultry had a 7.6 times higher risk for infection compared with workers who infrequently performed these behaviors. Despite frequent exposure to H5N1 virus, LBM workers showed evidence of only sporadic infection.

  12. Human Plague Risk: Spatial-Temporal Models

    Science.gov (United States)

    Pinzon, Jorge E.

    2010-01-01

    This chpater reviews the use of spatial-temporal models in identifying potential risks of plague outbreaks into the human population. Using earth observations by satellites remote sensing there has been a systematic analysis and mapping of the close coupling between the vectors of the disease and climate variability. The overall result is that incidence of plague is correlated to positive El Nino/Southem Oscillation (ENSO).

  13. Pathology of natural highly pathogenic avian influenza H5N1 infection in wild tufted ducks (Aythya fuligula).

    Science.gov (United States)

    Bröjer, Caroline; Agren, Erik O; Uhlhorn, Henrik; Bernodt, Karin; Mörner, Torsten; Jansson, Désirée S; Mattsson, Roland; Zohari, Siamak; Thorén, Peter; Berg, Mikael; Gavier-Widén, Dolores

    2009-09-01

    Highly pathogenic avian influenza (HPAI) subtype H5N1 is an infectious systemic viral disease that results in high morbidity and mortality in poultry, and has been reported in a wide range of wild bird species during the last few years. An outbreak of HPAI H5N1 occurred in wild birds in Sweden in 2006 that affected several duck species, geese, swans, gulls, and raptors. Tufted ducks (Aythya fuligula) accounted for the largest number of positive cases and, therefore, were selected for more in-depth histologic and immunohistochemical evaluations. The main histologic lesions associated with the presence of avian influenza antigen were found in the brain, pancreas, and upper respiratory tract. Other tissues in which influenza antigen was variably found included liver, lung, adrenal glands, kidneys, and peripheral nerve ganglia. The current study describes the pathology and viral tissue targeting of H5N1 by using histology, polymerase chain reaction, and immunohistochemistry, and highlights the range and variation in the presentation of the natural disease in tufted ducks.

  14. Quantitative Estimation of the Number of Contaminated Hatching Eggs Released from an Infected, Undetected Turkey Breeder Hen Flock During a Highly Pathogenic Avian Influenza Outbreak.

    Science.gov (United States)

    Malladi, Sasidhar; Weaver, J Todd; Alexander, Catherine Y; Middleton, Jamie L; Goldsmith, Timothy J; Snider, Timothy; Tilley, Becky J; Gonder, Eric; Hermes, David R; Halvorson, David A

    2015-09-01

    The regulatory response to an outbreak of highly pathogenic avian influenza (HPAI) in the United States may involve quarantine and stop movement orders that have the potential to disrupt continuity of operations in the U.S. turkey industry--particularly in the event that an uninfected breeder flock is located within an HPAI Control Area. A group of government-academic-industry leaders developed an approach to minimize the unintended consequences associated with outbreak response, which incorporates HPAI control measures to be implemented prior to moving hatching eggs off of the farm. Quantitative simulation models were used to evaluate the movement of potentially contaminated hatching eggs from a breeder henhouse located in an HPAI Control Area, given that active surveillance testing, elevated biosecurity, and a 2-day on-farm holding period were employed. The risk analysis included scenarios of HPAI viruses differing in characteristics as well as scenarios in which infection resulted from artificial insemination. The mean model-predicted number of internally contaminated hatching eggs released per movement from an HPAI-infected turkey breeder henhouse ranged from 0 to 0.008 under the four scenarios evaluated. The results indicate a 95% chance of no internally contaminated eggs being present per movement from an infected house before detection. Sensitivity analysis indicates that these results are robust to variation in key transmission model parameters within the range of their estimates from available literature. Infectious birds at the time of egg collection are a potential pathway of external contamination for eggs stored and then moved off of the farm; the predicted number of such infectious birds was estimated to be low. To date, there has been no evidence of vertical transmission of HPAI virus or low pathogenic avian influenza virus to day-old poults from hatching eggs originating from infected breeders. The application of risk analysis methods was beneficial

  15. Contrasted patterns of selection on MHC-linked microsatellites in natural populations of the Malagasy plague reservoir.

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    Charlotte Tollenaere

    Full Text Available Plague (Yersinia pestis infection is a highly virulent rodent disease that persists in many natural ecosystems. The black rat (Rattus rattus is the main host involved in the plague focus of the central highlands of Madagascar. Black rat populations from this area are highly resistant to plague, whereas those from areas in which the disease is absent (low altitude zones of Madagascar are susceptible. Various lines of evidence suggest a role for the Major Histocompatibility Complex (MHC in plague resistance. We therefore used the MHC region as a candidate for detecting signatures of plague-mediated selection in Malagasy black rats, by comparing population genetic structures for five MHC-linked microsatellites and neutral markers in two sampling designs. We first compared four pairs of populations, each pair including one population from the plague focus and one from the disease-free zone. Plague-mediated selection was expected to result in greater genetic differentiation between the two zones than expected under neutrality and this was observed for one MHC-class I-linked locus (D20Img2. For this marker as well as for four other MHC-linked loci, a geographic pattern of genetic structure was found at local scale within the plague focus. This pattern would be expected if plague selection pressures were spatially variable. Finally, another MHC-class I-linked locus (D20Rat21 showed evidences of balancing selection, but it seems more likely that this selection would be related to unknown pathogens more widely distributed in Madagascar than plague.

  16. Contrasted patterns of selection on MHC-linked microsatellites in natural populations of the Malagasy plague reservoir.

    Science.gov (United States)

    Tollenaere, Charlotte; Ivanova, Svilena; Duplantier, Jean-Marc; Loiseau, Anne; Rahalison, Lila; Rahelinirina, Soanandrasana; Brouat, Carine

    2012-01-01

    Plague (Yersinia pestis infection) is a highly virulent rodent disease that persists in many natural ecosystems. The black rat (Rattus rattus) is the main host involved in the plague focus of the central highlands of Madagascar. Black rat populations from this area are highly resistant to plague, whereas those from areas in which the disease is absent (low altitude zones of Madagascar) are susceptible. Various lines of evidence suggest a role for the Major Histocompatibility Complex (MHC) in plague resistance. We therefore used the MHC region as a candidate for detecting signatures of plague-mediated selection in Malagasy black rats, by comparing population genetic structures for five MHC-linked microsatellites and neutral markers in two sampling designs. We first compared four pairs of populations, each pair including one population from the plague focus and one from the disease-free zone. Plague-mediated selection was expected to result in greater genetic differentiation between the two zones than expected under neutrality and this was observed for one MHC-class I-linked locus (D20Img2). For this marker as well as for four other MHC-linked loci, a geographic pattern of genetic structure was found at local scale within the plague focus. This pattern would be expected if plague selection pressures were spatially variable. Finally, another MHC-class I-linked locus (D20Rat21) showed evidences of balancing selection, but it seems more likely that this selection would be related to unknown pathogens more widely distributed in Madagascar than plague.

  17. Differences in the Epidemiology of Human Cases of Avian Influenza A(H7N9) and A(H5N1) Viruses Infection

    Science.gov (United States)

    Qin, Ying; Horby, Peter W.; Tsang, Tim K.; Chen, Enfu; Gao, Lidong; Ou, Jianming; Nguyen, Tran Hien; Duong, Tran Nhu; Gasimov, Viktor; Feng, Luzhao; Wu, Peng; Jiang, Hui; Ren, Xiang; Peng, Zhibin; Li, Sa; Li, Ming; Zheng, Jiandong; Liu, Shelan; Hu, Shixiong; Hong, Rongtao; Farrar, Jeremy J.; Leung, Gabriel M.; Gao, George F.; Cowling, Benjamin J.; Yu, Hongjie

    2015-01-01

    Background. The pandemic potential of avian influenza viruses A(H5N1) and A(H7N9) remains an unresolved but critically important question. Methods. We compared the characteristics of sporadic and clustered cases of human H5N1 and H7N9 infection, estimated the relative risk of infection in blood-related contacts, and the reproduction number (R). Results. We assembled and analyzed data on 720 H5N1 cases and 460 H7N9 cases up to 2 November 2014. The severity and average age of sporadic/index cases of H7N9 was greater than secondary cases (71% requiring intensive care unit admission vs 33%, P = .007; median age 59 years vs 31, P H7N9. A higher proportion of H5N1 infections occurred in clusters (20%) compared to H7N9 (8%). The relative risk of infection in blood-related contacts of cases compared to unrelated contacts was 8.96 for H5N1 (95% CI, 1.30, 61.86) and 0.80 for H7N9 (95% CI, .32, 1.97). Conclusions. The results are consistent with an ascertainment bias towards severe and older cases for sporadic H7N9 but not for H5N1. The lack of evidence for ascertainment bias in sporadic H5N1 cases, the more pronounced clustering of cases, and the higher risk of infection in blood-related contacts, support the hypothesis that susceptibility to H5N1 may be limited and familial. This analysis suggests the potential pandemic risk may be greater for H7N9 than H5N1. PMID:25940354

  18. Multimeric recombinant M2e protein-based ELISA: a significant improvement in differentiating avian influenza infected chickens from vaccinated ones.

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    Farshid Hadifar

    Full Text Available Killed avian influenza virus (AIV vaccines have been used to control H5N1 infections in countries where the virus is endemic. Distinguishing vaccinated from naturally infected birds (DIVA in such situations however, has become a major challenge. Recently, we introduced the recombinant ectodomain of the M2 protein (M2e of H5N1 subtype as a novel tool for an ELISA based DIVA test. Despite being antigenic in natural infection the monomer form of the M2e used in ELISA had limited antigenicity and consequently poor diagnostic capability. To address this shortcoming, we evaluated the use of four tandem copies of M2e (tM2e for increased efficiency of M2e antibody detection. The tM2e gene of H5N1 strain from Indonesia (A/Indonesia/CDC540/2006 was cloned into a pMAL- p4x expression vector and expressed in E.coli as a recombinant tM2e-MBP or M2e-MBP proteins. Both of these, M2e and tM2e antigens reacted with sera obtained from chickens following live H5N1 infection but not with sera from vaccinated birds. A significantly stronger M2e antibody reaction was observed with the tM2e compared to M2e antigen. Western blotting also supported the superiority of tM2e over M2e in detection of specific M2e antibodies against live H5N1 infection. Results from this study demonstrate that M2e tetramer is a better antigen than single M2e and could be more suitable for an ELISA based DIVA test.

  19. Yersinia pestis endowed with increased cytotoxicity is avirulent in a bubonic plague model and induces rapid protection against pneumonic plague.

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    Ayelet Zauberman

    Full Text Available An important virulence strategy evolved by bacterial pathogens to overcome host defenses is the modulation of host cell death. Previous observations have indicated that Yersinia pestis, the causative agent of plague disease, exhibits restricted capacity to induce cell death in macrophages due to ineffective translocation of the type III secretion effector YopJ, as opposed to the readily translocated YopP, the YopJ homologue of the enteropathogen Yersinia enterocolitica Oratio8. This led us to suggest that reduced cytotoxic potency may allow pathogen propagation within a shielded niche, leading to increased virulence. To test the relationship between cytotoxic potential and virulence, we replaced Y. pestis YopJ with YopP. The YopP-expressing Y. pestis strain exhibited high cytotoxic activity against macrophages in vitro. Following subcutaneous infection, this strain had reduced ability to colonize internal organs, was unable to induce septicemia and exhibited at least a 10(7-fold reduction in virulence. Yet, upon intravenous or intranasal infection, it was still as virulent as the wild-type strain. The subcutaneous administration of the cytotoxic Y. pestis strain appears to activate a rapid and potent systemic, CTL-independent, immunoprotective response, allowing the organism to overcome simultaneous coinfection with 10,000 LD(50 of virulent Y. pestis. Moreover, three days after subcutaneous administration of this strain, animals were also protected against septicemic or primary pneumonic plague. Our findings indicate that an inverse relationship exists between the cytotoxic potential of Y. pestis and its virulence following subcutaneous infection. This appears to be associated with the ability of the engineered cytotoxic Y. pestis strain to induce very rapid, effective and long-lasting protection against bubonic and pneumonic plague. These observations have novel implications for the development of vaccines/therapies against Y. pestis and shed

  20. Avian Research

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Aims and Scope Avian Research is an open access,peer-reviewed journal publishing high quality research and review articles on all aspects of ornithology from all over the world.It aims to report the latest and most significant progress in ornithology and to encourage exchange of ideas among international ornithologists.As an Open Access journal,

  1. Avian Research

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    Aims and Scope Avian Research is an open access,peer-reviewed journal publishing high quality research and review articles on all aspects of ornithology from all over the world.It aims to report the latest and most significant progress in ornithology and to encourage exchange of ideas among international ornithologists.As an Open Access journal,

  2. Avian Research

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    <正>Aims and Scope Avian Research is an open access,peer-reviewed journal publishing high quality research and review articles on all aspects of ornithology from all over the world.It aims to report the latest and most significant progress in ornithology and to encourage exchange of ideas among international ornithologists.As an Open Access journal,

  3. Avian Research

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    <正>Aims and Scope Avian Research is an open access,peer-reviewed journal publishing high quality research and review articles on all aspects of ornithology from all over the world.It aims to report the latest and most significant progress in ornithology and to encourage exchange of ideas among international ornithologists.As an Open Access journal,

  4. Primary case of human pneumonic plague occurring in a Himalayan marmot natural focus area Gansu Province, China

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    Pengfei Ge

    2015-04-01

    Full Text Available A case of primary pneumonic plague (PPP caused by Yersinia pestis is reported. This case occurred in the largest plague area in China. The patient died after contact with a dog that had captured an infected marmot. Three of 151 contacts were shown to be positive for antibody against F1 antigen by indirect hemagglutination assay, but none had clinical symptoms. There was no secondary case.

  5. Primary case of human pneumonic plague occurring in a Himalayan marmot natural focus area Gansu Province, China.

    Science.gov (United States)

    Ge, Pengfei; Xi, Jinxiao; Ding, Jun; Jin, Fachang; Zhang, Hong; Guo, Limin; Zhang, Jie; Li, Junlin; Gan, Zhiqiang; Wu, Bin; Liang, Junrong; Wang, Xin; Wang, Xinhua

    2015-04-01

    A case of primary pneumonic plague (PPP) caused by Yersinia pestis is reported. This case occurred in the largest plague area in China. The patient died after contact with a dog that had captured an infected marmot. Three of 151 contacts were shown to be positive for antibody against F1 antigen by indirect hemagglutination assay, but none had clinical symptoms. There was no secondary case.

  6. Co-infection of Avian Leukosis Virus and Salmonella pullorum with the Preliminary Eradication in Breeders of Chinese Local “ShouGuang” Chickens

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    Jian Qiang Huang, Jing Kai Xin, Cui Mao, Feng Zhong and Jia Qian Chai*

    2013-11-01

    Full Text Available The study was designed to investigate the infection status and to finish the preliminary eradication of avian leukosis virus (ALV and Salmonella pullorum (SP in breeders of Chinese local “ShouGuang” chickens. ALV antigen and antibody was tested via ELISA, and SP antibody was detected by serum plate agglutination test (SPAT. The etiology and pathology was also studied. The ALV-P27 antigen, ALV-A/B and SP antibody positive chickens were eliminated in turn, and then the negative were retained as the breeder flocks. The results showed that the positive rate of antigen to ALV-P27, antibody to ALV-A/B, ALV-J and SP was 57.8, 6.7, 0 and 17.8% in this breeder farm, respectively. The co-infection of ALV and SP was confirmed and the positive rate of both SP and ALV-P27 or ALV-A/B was 10 and 1%, respectively. There were obvious tumor nodules and lymphoid tumor cells in the comb, liver and spleen of the co-infected chickens. The degenerative and atrophic ovarian follicles, inflammatory cell infiltration in muscle biopsies were also found. The elimination rate of ALV-p27, ALV-A/B and SP positive chickens was 55.4, 13 and 6.1%, respectively. The final amount of the breeder conservation was 309 chickens. In conclusion, the co-infection of ALV-B and SP was found and more emphasis should be given on its prevention; the preliminary eradication of “ShouGuang” breeder chickens was finished.

  7. Immunohistochemistry for detection of avian infectious bronchitis virus strain M41 in the proventriculus and nervous system of experimentally infected chicken embryos

    Directory of Open Access Journals (Sweden)

    Keil Günther M

    2009-02-01

    Full Text Available Abstract Background Infectious bronchitis virus primarily induces a disease of the respiratory system, different IBV strains may show variable tissue tropisms and also affect the oviduct and the kidneys. Proventriculitis was also associated with some new IBV strains. Aim of this study was to investigate by immunohistochemistry (IHC the tissue tropism of avian infectious bronchitis virus (IBV strain M41 in experimentally infected chicken embryos. Results To this end chicken embryos were inoculated in the allantoic sac with 103 EID50 of IBV M41 at 10 days of age. At 48, 72, and 120 h postinoculation (PI, embryos and chorioallantoic membranes (CAM were sampled, fixed, and paraffin-wax embedded. Allantoic fluid was also collected and titrated in chicken embryo kidney cells (CEK. The sensitivity of IHC in detecting IBV antigens in the CAM of inoculated eggs matched the virus reisolation and detection in CEK. Using IHC, antigens of IBV were detected in nasal epithelium, trachea, lung, spleen, myocardial vasculature, liver, gastrointestinal tract, kidney, skin, sclera of the eye, spinal cord, as well as in brain neurons of the inoculated embryos. These results were consistent with virus isolation and denote the wide tissue tropism of IBV M41 in the chicken embryo. Most importantly, we found infection of vasculature and smooth muscle of the proventriculus which has not seen before with IBV strain M41. Conclusion IHC can be an additional useful tool for diagnosis of IBV infection in chickens and allows further studies to foster a deeper understanding of the pathogenesis of infections with IBV strains of different virulence. Moreover, these results underline that embryonic tissues in addition to CAM could be also used as possible source to generate IBV antigens for diagnostic purposes.

  8. Apoptosis induction and release of inflammatory cytokines in the oviduct of egg-laying hens experimentally infected with H9N2 avian influenza virus.

    Science.gov (United States)

    Wang, Jingyu; Tang, Chao; Wang, Qiuzhen; Li, Ruiqiao; Chen, Zhanli; Han, Xueying; Wang, Jing; Xu, Xingang

    2015-06-12

    The H9N2 subtype avian influenza virus (AIV) can cause serious damage to the reproductive tract of egg-laying hens, leading to severe egg-drop and poor egg shell quality. However, previous studies in relation to the oviductal-dysfunction resulted from this agent have not clearly been elucidated. In this study, apoptosis and pathologic changes in the oviducts of egg-laying hens caused by H9N2 AIV were evaluated. To understand the immune response in the pathogenic processes, 30-week old specific pathogen free (SPF) egg-laying hens inoculated with H9N2 subtype of AIV through combined intra-ocular and intra-nasal routes. H9N2 AIV infection resulted in oviductal lesions, triggered apoptosis and expression of immune related genes accompanied with infiltration of CD3(+)CD4(+) and CD3(+)CD8α(+) cells. Significant tissue damage and apoptosis were observed in the five oviductal parts (infundibulum, magnum, isthmus, uterus and vagina) at 5 days post-inoculation (dpi). Furthermore, immune-related genes, including chicken TLR3 (7, 21), MDA5, IL-2, IFN-β, CXCLi1, CXCLi2, XCL1, XCR1 and CCR5 showed variation in the egg-laying hens infected with H9N2 AIV. Notably, mRNA expression of IFN-α was suppressed during the infection. These results show distinct expression patterns of inflammatory cytokines and chemokines amongst segments of the oviduct. Differential gene expression of inflammatory cytokines and lymphocytes aggregation occurring in oviducts may initiate the infected tissue in response to virus replication which may eventually lead to excessive cellular apoptosis and tissue damage.

  9. Detection and characterization of two co-infection variant strains of avian orthoreovirus (ARV) in young layer chickens using next-generation sequencing (NGS).

    Science.gov (United States)

    Tang, Yi; Lin, Lin; Sebastian, Aswathy; Lu, Huaguang

    2016-04-19

    Using next-generation sequencing (NGS) for full genomic characterization studies of the newly emerging avian orthoreovirus (ARV) field strains isolated in Pennsylvania poultry, we identified two co-infection ARV variant strains from one ARV isolate obtained from ARV-affected young layer chickens. The de novo assembly of the ARV reads generated 19 contigs of two different ARV variant strains according to 10 genome segments of each ARV strain. The two variants had the same M2 segment. The complete genomes of each of the two variant strains were 23,493 bp in length, and 10 dsRNA segments ranged from 1192 bp (S4) to 3958 bp (L1), encoding 12 viral proteins. Sequence comparison of nucleotide (nt) and amino acid (aa) sequences of all 10 genome segments revealed 58.1-100% and 51.4-100% aa identity between the two variant strains, and 54.3-89.4% and 49.5-98.1% aa identity between the two variants and classic vaccine strains. Phylogenetic analysis revealed a moderate to significant nt sequence divergence between the two variant and ARV reference strains. These findings have demonstrated the first naturally occurring co-infection of two ARV variants in commercial young layer chickens, providing scientific evidence that multiple ARV strains can be simultaneously present in one host species of chickens.

  10. Avian Influenza in Birds

    Science.gov (United States)

    ... this? Submit Button Past Newsletters Avian Influenza in Birds Language: English Español Recommend on Facebook Tweet ... illness. Top of Page Avian Influenza in Wild Birds Avian influenza A viruses have been isolated from ...

  11. An overview on avian influenza

    Directory of Open Access Journals (Sweden)

    Nelson Rodrigo da Silva Martins

    2012-06-01

    Full Text Available Avian influenza (AI is considered an exotic disease in the Brazilian poultry industry, according to the National Avian Health Program (PNSA, with permanent monitoring of domestic, exotic and native avian species. Brazil presents privileged environmental conditions of reduced risk. In addition, all commercial poultry and conservation holdings are registered in state or national inventories and geographically located (GPS for health control. Poultry health standards are adopted for the conformity to the international market, mostly for the intensified poultry destined for exportation, but also for companion exotic and native conservation facilities. Guidelines for monitoring and the diagnosis of AI are published by the PNSA and follow the standards proposed by the international health code (World Organization for Animal Health, Organization International des Epizooties - OIE and insure the free of status for avian influenza virus (AIV of LPAIV-low pathogenicity AIV and HPAIV-high pathogenicity AIV. In addition, the infections by mesogenic and velogenic Newcastle disease virus, Mycoplasma gallisepticum, M. synoviae and M. meleagridis, Salmonella enteric subspecies enterica serovar Gallinarum biovars Gallinarum and Pullorum are eradicated from reproduction. Controlled infections by S.enterica subspecies enterica serovars Enteritidis and Typhimurium are monitored for breeders. The vaccination of chickens in ovo or at hatch against Marek's disease is mandatory. Broiler production is an indoor activity, confinement which insures biosecurity, with safe distances from the potential AIV reservoir avian species. Worldwide HPAIV H5N1 notifications to the OIE, in March 2011, included 51 countries.

  12. Remote sensing for landscape epidemiology : spatial analysis of plague hosts in Kazakhstan

    NARCIS (Netherlands)

    Wilschut, L.I.

    2015-01-01

    The spatial distribution of hosts is a crucial aspect for the understanding of infectious disease dynamics. In Kazakhstan, the great gerbil (Rhombomys opimus) is the main host for plague (Yersinia pestis infection) and poses a public health threat, yet their spatial distribution is unknown. Great ge

  13. The innate immune response may be important for surviving plague in wild Gunnison's prairie dogs.

    Science.gov (United States)

    Busch, Joseph D; Van Andel, Roger; Stone, Nathan E; Cobble, Kacy R; Nottingham, Roxanne; Lee, Judy; VerSteeg, Michael; Corcoran, Jeff; Cordova, Jennifer; Van Pelt, William; Shuey, Megan M; Foster, Jeffrey T; Schupp, James M; Beckstrom-Sternberg, Stephen; Beckstrom-Sternberg, James; Keim, Paul; Smith, Susan; Rodriguez-Ramos, Julia; Williamson, Judy L; Rocke, Tonie E; Wagner, David M

    2013-10-01

    Prairie dogs (Cynomys spp.) are highly susceptible to Yersinia pestis, with ≥99% mortality reported from multiple studies of plague epizootics. A colony of Gunnison's prairie dogs (Cynomys gunnisoni) in the Aubrey Valley (AV) of northern Arizona appears to have survived several regional epizootics of plague, whereas nearby colonies have been severely affected by Y. pestis. To examine potential mechanisms accounting for survival in the AV colony, we conducted a laboratory Y. pestis challenge experiment on 60 wild-caught prairie dogs from AV and from a nearby, large colony with frequent past outbreaks of plague, Espee (n = 30 per colony). Test animals were challenged subcutaneously with the fully virulent Y. pestis strain CO92 at three doses: 50, 5,000, and 50,000 colony-forming units (cfu); this range is lethal in black-tailed prairie dogs (Cynomys ludovicianus). Contrary to our expectations, only 40% of the animals died. Although mortality trended higher in the Espee colony (50%) compared with AV (30%), the differences among infectious doses were not statistically significant. Only 39% of the survivors developed moderate to high antibody levels to Y. pestis, indicating that mechanisms other than humoral immunity are important in resistance to plague. The ratio of neutrophils to lymphocytes was not correlated with plague survival in this study. However, several immune proteins with roles in innate immunity (VCAM-1, CXCL-1, and vWF) were upregulated during plague infection and warrant further inquiry into their role for protection against this disease. These results suggest plague resistance exists in wild populations of the Gunnison's prairie dog and provide important directions for future studies.

  14. The innate immune response may be important for surviving plague in wild Gunnison's prairie dogs

    Science.gov (United States)

    Busch, Joseph D.; Van Andel, Roger; Stone, Nathan E.; Cobble, Kacy R.; Nottingham, Roxanne; Lee, Judy; VerSteeg, Michael; Corcoran, Jeff; Cordova, Jennifer; Van Pelt, William E.; Shuey, Megan M.; Foster, Jeffrey T.; Schupp, James M.; Beckstrom-Sternberg, Stephen; Beckstrom-Sternberg, James; Keim, Paul; Smith, Susan; Rodriguez-Ramos, Julia; Williamson, Judy L.; Rocke, Tonie E.; Wagner, David M.

    2013-01-01

    Prairie dogs (Cynomys spp.) are highly susceptible to Yersinia pestis, with ≥99% mortality reported from multiple studies of plague epizootics. A colony of Gunnison's prairie dogs (Cynomys gunnisoni) in the Aubrey Valley (AV) of northern Arizona appears to have survived several regional epizootics of plague, whereas nearby colonies have been severely affected by Y. pestis. To examine potential mechanisms accounting for survival in the AV colony, we conducted a laboratory Y. pestis challenge experiment on 60 wild-caught prairie dogs from AV and from a nearby, large colony with frequent past outbreaks of plague, Espee (n = 30 per colony). Test animals were challenged subcutaneously with the fully virulent Y. pestis strain CO92 at three doses: 50, 5,000, and 50,000 colony-forming units (cfu); this range is lethal in black-tailed prairie dogs (Cynomys ludovicianus). Contrary to our expectations, only 40% of the animals died. Although mortality trended higher in the Espee colony (50%) compared with AV (30%), the differences among infectious doses were not statistically significant. Only 39% of the survivors developed moderate to high antibody levels to Y. pestis, indicating that mechanisms other than humoral immunity are important in resistance to plague. The ratio of neutrophils to lymphocytes was not correlated with plague survival in this study. However, several immune proteins with roles in innate immunity (VCAM-1, CXCL-1, and vWF) were upregulated during plague infection and warrant further inquiry into their role for protection against this disease. These results suggest plague resistance exists in wild populations of the Gunnison's prairie dog and provide important directions for future studies.

  15. Mountain plover responses to plague in Montana.

    Science.gov (United States)

    Dinsmore, Stephen J; Smith, Mark D

    2010-01-01

    Plague is a bacterial (Yersinia pestis) disease that causes epizootic die-offs in black-tailed prairie dog (Cynomys ludovicianus) populations in the North American Great Plains. Through their grazing and burrowing, prairie dogs modify vegetation and landscape structure on their colonies in ways that affect other grassland species. Plague epizootics on prairie dog colonies can have indirect effects on species associated with colonies. The mountain plover (Charadrius montanus) preferentially nests on black-tailed prairie dog colonies and is thus negatively impacted by the loss of prairie dogs. We studied the effects of plague and colony spatial characteristics on the occupancy of 81 prairie dog colonies by nesting plovers in Phillips County, Montana, during a 13-year period (1995-2007). We used a robust design patch occupancy model to investigate how colony occupancy and extinction and colonization rates were affected by plague history, colony size, and colony shape. Here extinction and colonization rates refer to the probability that a colony loses/gains plovers in a subsequent nesting season, given that it had/lacked plovers in that breeding season. Colony occupancy was best explained by a model with no annual variation or plague effects. Colony extinction rates were driven by a combination of a quadratic of colony area, a 3-year plague response, and a measure of colony shape. Conversely, colonization rates were best explained by a model with a 4-year plague response. The estimated annual proportion of colonies occupied by plovers was 0.75 (95% confidence interval = 0.57-0.87). Estimated extinction probability ranged from a low of 0.07 (standard error [SE] = 0.02) in 2002 to a high of 0.25 (SE = 0.03) in 1995; colonization probability ranged from 0.24 (SE = 0.05) in 2006 to 0.35 (SE = 0.05) in 2000. Our results highlight how a bird that depends on prairie dogs for nesting habitat responds to plague history and other spatial characteristics of the colony. Ultimately

  16. Experimental infection of highly and low pathogenic avian influenza viruses to chickens, ducks, tree sparrows, jungle crows, and black rats for the evaluation of their roles in virus transmission.

    Science.gov (United States)

    Hiono, Takahiro; Okamatsu, Masatoshi; Yamamoto, Naoki; Ogasawara, Kohei; Endo, Mayumi; Kuribayashi, Saya; Shichinohe, Shintaro; Motohashi, Yurie; Chu, Duc-Huy; Suzuki, Mizuho; Ichikawa, Takaya; Nishi, Tatsuya; Abe, Yuri; Matsuno, Keita; Tanaka, Kazuyuki; Tanigawa, Tsutomu; Kida, Hiroshi; Sakoda, Yoshihiro

    2016-01-01

    Highly pathogenic avian influenza viruses (HPAIVs) have spread in both poultry and wild birds. Determining transmission routes of these viruses during an outbreak is essential for the control of avian influenza. It has been widely postulated that migratory ducks play crucial roles in the widespread dissemination of HPAIVs in poultry by carrying viruses along with their migrations; however close contacts between wild migratory ducks and poultry are less likely in modern industrial poultry farming settings. Therefore, we conducted experimental infections of HPAIVs and low pathogenic avian influenza viruses (LPAIVs) to chickens, domestic ducks, tree sparrows, jungle crows, and black rats to evaluate their roles in virus transmission. The results showed that chickens, ducks, sparrows, and crows were highly susceptible to HPAIV infection. Significant titers of virus were recovered from the sparrows and crows infected with HPAIVs, which suggests that they potentially play roles of transmission of HPAIVs to poultry. In contrast, the growth of LPAIVs was limited in each of the animals tested compared with that of HPAIVs. The present results indicate that these common synanthropes play some roles in influenza virus transmission from wild birds to poultry.

  17. A modeling study of human infections with avian influenza A H7N9 virus in mainland China

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    Zhifei Liu

    2015-12-01

    Conclusions: Screening and culling infected poultry is a critical measure for preventing human H7N9 infections in the long term. This model may provide important insights for decision-making on a national intervention strategy for the long-term control of the H7N9 virus epidemic.

  18. Demographic and spatio-temporal variation in human plague at a persistent focus in Tanzania

    DEFF Research Database (Denmark)

    Davis, S; Makundi, R H; Machang'u, R S

    2006-01-01

    Human plague in the Western Usambara Mountains in Tanzania has been a public health problem since the first outbreak in 1980. The wildlife reservoir is unknown and eradication measures that have proved effective elsewhere in Tanzania appear to fail in this region. We use census data from 2002...... and hospital records kept since 1986 to describe the temporal, spatial and demographic variation in human plague. A seasonal peak in cases occurs from December to February with the numbers of cases during this peak varying between 0 and 1150. Variation in incidence, calculated for each village as the mean...... number of cases per thousand inhabitants per year, indicates that human plague is concentrated around a group of three neighbouring, relatively isolated, high-altitude villages; Nywelo, Madala and Gologolo. However, there was no evidence that these villages were acting as a source of infection...

  19. Seroprevalence of hantavirus and Yersinia pestis antibodies in professionals from the Plague Control Program

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    Erika de Cassia Vieira da Costa

    2013-07-01

    Full Text Available Introduction Professionals who handle rodents in the field and in the laboratory are at risk of infection by the microorganisms harbored by these animals. Methods Serum samples from professionals involved in rodent and Yersinia pestis handling in field or laboratory work were analyzed to determine hantavirus and plague seroprevalence and to establish a relationship between these activities and reports of illnesses. Results Two individuals had antibodies against hantavirus, and two harbored antibodies against the plague; none of the individuals had experienced an illness related to their duties. Conclusions These results confirm the risks of hantavirus- and plague-related field and laboratory activities and the importance of protective measures for such work.

  20. Sylvatic plague reduces genetic variability in black-tailed prairie dogs.

    Science.gov (United States)

    Trudeau, Kristie M; Britten, Hugh B; Restani, Marco

    2004-04-01

    Small, isolated populations are vulnerable to loss of genetic diversity through in-breeding and genetic drift. Sylvatic plague due to infection by the bacterium Yersinia pestis caused an epizootic in the early 1990s resullting in declines and extirpations of many black-tailed prairie dog (Cynomys ludovicianus) colonies in north-central Montana, USA. Plague-induced population bottlenecks may contribute to significant reductions in genetic variability. In contrast, gene flow maintains genetic variability within colonies. We investigated the impacts of the plague epizootic and distance to nearest colony on levels of genetic variability in six prairie dog colonies sampled between June 1999 and July 2001 using 24 variable randomly amplified polymorphic DNA (RAPD) markers. Number of effective alleles per locus (n(e)) and gene diversity (h) were significantly decreased in the three colonies affected by plague that were recovering from the resulting bottlenecks compared with the three colonies that did not experience plague. Genetic variability was not significantly affected by geographic distance between colonies. The majority of variance in gene fieqnencies was found within prairie clog colonies. Conservation of genetic variability in black-tailed prairie dogs will require the preservation of both large and small colony complexes and the gene flow amonog them.

  1. Current Perspectives on Plague Vector Control in Madagascar: Susceptibility Status of Xenopsylla cheopis to 12 Insecticides.

    Science.gov (United States)

    Miarinjara, Adélaïde; Boyer, Sébastien

    2016-02-01

    Plague is a rodent disease transmissible to humans by infected flea bites, and Madagascar is one of the countries with the highest plague incidence in the world. This study reports the susceptibility of the main plague vector Xenopsylla cheopis to 12 different insecticides belonging to 4 insecticide families (carbamates, organophosphates, pyrethroids and organochlorines). Eight populations from different geographical regions of Madagascar previously resistant to deltamethrin were tested with a World Health Organization standard bioassay. Insecticide susceptibility varied amongst populations, but all of them were resistant to six insecticides belonging to pyrethroid and carbamate insecticides (alphacypermethrin, lambdacyhalothrin, etofenprox, deltamethrin, bendiocarb and propoxur). Only one insecticide (dieldrin) was an efficient pulicide for all flea populations. Cross resistances were suspected. This study proposes at least three alternative insecticides (malathion, fenitrothion and cyfluthrin) to replace deltamethrin during plague epidemic responses, but the most efficient insecticide may be different for each population studied. We highlight the importance of continuous insecticide susceptibility surveillance in the areas of high plague risk in Madagascar.

  2. Current Perspectives on Plague Vector Control in Madagascar: Susceptibility Status of Xenopsylla cheopis to 12 Insecticides.

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    Adélaïde Miarinjara

    2016-02-01

    Full Text Available Plague is a rodent disease transmissible to humans by infected flea bites, and Madagascar is one of the countries with the highest plague incidence in the world. This study reports the susceptibility of the main plague vector Xenopsylla cheopis to 12 different insecticides belonging to 4 insecticide families (carbamates, organophosphates, pyrethroids and organochlorines. Eight populations from different geographical regions of Madagascar previously resistant to deltamethrin were tested with a World Health Organization standard bioassay. Insecticide susceptibility varied amongst populations, but all of them were resistant to six insecticides belonging to pyrethroid and carbamate insecticides (alphacypermethrin, lambdacyhalothrin, etofenprox, deltamethrin, bendiocarb and propoxur. Only one insecticide (dieldrin was an efficient pulicide for all flea populations. Cross resistances were suspected. This study proposes at least three alternative insecticides (malathion, fenitrothion and cyfluthrin to replace deltamethrin during plague epidemic responses, but the most efficient insecticide may be different for each population studied. We highlight the importance of continuous insecticide susceptibility surveillance in the areas of high plague risk in Madagascar.

  3. Current Perspectives on Plague Vector Control in Madagascar: Susceptibility Status of Xenopsylla cheopis to 12 Insecticides

    Science.gov (United States)

    Miarinjara, Adélaïde; Boyer, Sébastien

    2016-01-01

    Plague is a rodent disease transmissible to humans by infected flea bites, and Madagascar is one of the countries with the highest plague incidence in the world. This study reports the susceptibility of the main plague vector Xenopsylla cheopis to 12 different insecticides belonging to 4 insecticide families (carbamates, organophosphates, pyrethroids and organochlorines). Eight populations from different geographical regions of Madagascar previously resistant to deltamethrin were tested with a World Health Organization standard bioassay. Insecticide susceptibility varied amongst populations, but all of them were resistant to six insecticides belonging to pyrethroid and carbamate insecticides (alphacypermethrin, lambdacyhalothrin, etofenprox, deltamethrin, bendiocarb and propoxur). Only one insecticide (dieldrin) was an efficient pulicide for all flea populations. Cross resistances were suspected. This study proposes at least three alternative insecticides (malathion, fenitrothion and cyfluthrin) to replace deltamethrin during plague epidemic responses, but the most efficient insecticide may be different for each population studied. We highlight the importance of continuous insecticide susceptibility surveillance in the areas of high plague risk in Madagascar. PMID:26844772

  4. Evidence of Yersinia pestis DNA from fleas in an endemic plague area of Zambia

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    Hang'ombe Bernard M

    2012-01-01

    Full Text Available Abstract Background Yersinia pestis is a bacterium that causes plague which infects a variety of mammals throughout the world. The disease is usually transmitted among wild rodents through a flea vector. The sources and routes of transmission of plague are poorly researched in Africa, yet remains a concern in several sub-Saharan countries. In Zambia, the disease has been reported on annual basis with up to 20 cases per year, without investigating animal reservoirs or vectors that may be responsible in the maintenance and propagation of the bacterium. In this study, we undertook plague surveillance by using PCR amplification of the plasminogen activator gene in fleas. Findings Xenopsylla species of fleas were collected from 83 rodents trapped in a plague endemic area of Zambia. Of these rodents 5 had fleas positive (6.02% for Y. pestis plasminogen activator gene. All the Y. pestis positive rodents were gerbils. Conclusions We conclude that fleas may be responsible in the transmission of Y. pestis and that PCR may provide means of plague surveillance in the endemic areas of Zambia.

  5. Advances on study of plague indicator animals in the plague nature foci in China%鼠疫自然疫源地鼠疫指示动物研究进展

    Institute of Scientific and Technical Information of China (English)

    王治宇; 张志霞; 刘海翔; 杨建明; 王海峰; 杨顺林; 史献明; 杜国义

    2016-01-01

    鼠疫是一种以啮齿类动物为主要宿主的自然疫源性疾病。目前发现可自然感染鼠疫耶尔森菌(鼠疫菌)的动物有223种。鼠疫指示动物是指在自然界中可自然感染鼠疫菌,对其具有低敏感性、高抗性的动物,该类动物在鼠疫菌的保存和传播中有重要作用。通过对高抗动物的调查和研究,为早期发现和追踪疫情提供科学依据。%Plague is an enzootic infectious disease. The rodent animals are primary reservoir hosts of plague. There are 223 kinds of animal which have been found to be infected with plague in nature. Plague⁃tolerant animals which can be naturally infected with plague without symptoms serve as plague⁃indicators. These animals also play a very important role in the spread of the plague. The research of plague⁃indicating animals was reviewed in this paper which provides scientific basis for plague prevention and control in China.

  6. Epidemiological and clinical characteristics and risk factors for death of patients with avian influenza A H7N9 virus infection from Jiangsu Province, Eastern China.

    Directory of Open Access Journals (Sweden)

    Hong Ji

    Full Text Available BACKGROUND: A novel avian influenza A (H7N9 virus has caused great morbidity as well as mortality since its emergence in Eastern China in February 2013. However, the possible risk factors for death are not yet fully known. METHODS AND FINDINGS: Patients with H7N9 virus infection between March 1 and August 14, 2013 in Jiangsu province were enrolled. Data were collected with a standard form. Mean or percentage was used to describe the features, and Fisher's exact test or t-test test was used to compare the differences between fatal and nonfatal cases with H7N9 virus infection. A total of 28 patients with H7N9 virus infection were identified among whom, nine (32.1% died. The median age of fatal cases was significant higher than nonfatal cases (P<0.05. Patients with older age were more strongly associated with increased odds of death (OR = 30.0; 95% CI, 2.85-315.62. Co-morbidity with chronic lung disease and hypertension were risk factors for mortality (OR = 14.40; 95% CI, 1.30-159.52, OR = 6.67; 95% CI, 1.09-40.43, respectively. Moreover, the presence of either bilateral lung inflammation or pulmonary consolidation on chest imaging on admission was related with fatal outcome (OR = 7.00; 95%CI, 1.10-44.61. Finally, dynamic monitoring showed that lymphopenia was more significant in fatal group than in nonfatal group from day 11 to week five (P<0.05. The decrease in oxygenation indexes were observed in most cases and more significantly in fatal cases after week three (P<0.05, and the value of nearly all fatal cases were below 200 mmHg during our evaluation period. CONCLUSIONS: Among cases with H7N9 virus infection, increased age accompanied by co-morbidities was the risk of death. The severity of lung infection at admission, the persistence of lymphocytopenia, and the extended duration of lower oxygenation index all contributed to worsened outcomes of patients with H7N9 virus infection.

  7. Highly pathogenic avian influenza virus H5N1 infection in a long-distance migrant shorebird under migratory and non-migratory states.

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    Leslie A Reperant

    Full Text Available Corticosterone regulates physiological changes preparing wild birds for migration. It also modulates the immune system and may lead to increased susceptibility to infection, with implications for the spread of pathogens, including highly pathogenic avian influenza virus (HPAIV H5N1. The red knot (Calidris canutus islandica displays migratory changes in captivity and was used as a model to assess the effect of high plasma concentration of corticosterone on HPAIV H5N1 infection. We inoculated knots during pre-migration (N = 6, fueling (N = 5, migration (N = 9 and post-migration periods (N = 6. Knots from all groups shed similar viral titers for up to 5 days post-inoculation (dpi, peaking at 1 to 3 dpi. Lesions of acute encephalitis, associated with virus replication in neurons, were seen in 1 to 2 knots per group, leading to neurological disease and death at 5 to 11 dpi. Therefore, the risk of HPAIV H5N1 infection in wild birds and of potential transmission between wild birds and poultry may be similar at different times of the year, irrespective of wild birds' migratory status. However, in knots inoculated during the migration period, viral shedding levels positively correlated with pre-inoculation plasma concentration of corticosterone. Of these, knots that did not become productively infected had lower plasma concentration of corticosterone. Conversely, elevated plasma concentration of corticosterone did not result in an increased probability to develop clinical disease. These results suggest that birds with elevated plasma concentration of corticosterone at the time of migration (ready to migrate may be more susceptible to acquisition of infection and shed higher viral titers--before the onset of clinical disease--than birds with low concentration of corticosterone (not ready for take-off. Yet, they may not be more prone to the development of clinical disease. Therefore, assuming no effect of sub-clinical infection on the

  8. Highly pathogenic avian influenza virus H5N1 infection in a long-distance migrant shorebird under migratory and non-migratory states.

    Science.gov (United States)

    Reperant, Leslie A; van de Bildt, Marco W G; van Amerongen, Geert; Buehler, Debbie M; Osterhaus, Albert D M E; Jenni-Eiermann, Susi; Piersma, Theunis; Kuiken, Thijs

    2011-01-01

    Corticosterone regulates physiological changes preparing wild birds for migration. It also modulates the immune system and may lead to increased susceptibility to infection, with implications for the spread of pathogens, including highly pathogenic avian influenza virus (HPAIV) H5N1. The red knot (Calidris canutus islandica) displays migratory changes in captivity and was used as a model to assess the effect of high plasma concentration of corticosterone on HPAIV H5N1 infection. We inoculated knots during pre-migration (N = 6), fueling (N = 5), migration (N = 9) and post-migration periods (N = 6). Knots from all groups shed similar viral titers for up to 5 days post-inoculation (dpi), peaking at 1 to 3 dpi. Lesions of acute encephalitis, associated with virus replication in neurons, were seen in 1 to 2 knots per group, leading to neurological disease and death at 5 to 11 dpi. Therefore, the risk of HPAIV H5N1 infection in wild birds and of potential transmission between wild birds and poultry may be similar at different times of the year, irrespective of wild birds' migratory status. However, in knots inoculated during the migration period, viral shedding levels positively correlated with pre-inoculation plasma concentration of corticosterone. Of these, knots that did not become productively infected had lower plasma concentration of corticosterone. Conversely, elevated plasma concentration of corticosterone did not result in an increased probability to develop clinical disease. These results suggest that birds with elevated plasma concentration of corticosterone at the time of migration (ready to migrate) may be more susceptible to acquisition of infection and shed higher viral titers--before the onset of clinical disease--than birds with low concentration of corticosterone (not ready for take-off). Yet, they may not be more prone to the development of clinical disease. Therefore, assuming no effect of sub-clinical infection on the likelihood of

  9. No evidence of infection or exposure to Highly Pathogenic Avian Influenzas in peridomestic wildlife on an affected poultry facility

    Science.gov (United States)

    Grear, Daniel A.; Dusek, Robert J.; Walsh, Daniel P.; Hall, Jeffrey S.

    2017-01-01

    We evaluated the potential transmission of avian influenza viruses (AIV) in wildlife species in three settings in association with an outbreak at a poultry facility: 1) small birds and small mammals on a poultry facility that was affected with highly pathogenic AIV (HPAIV) in April 2015; 2) small birds and small mammals on a nearby poultry facility that was unaffected by HPAIV; and 3) small birds, small mammals, and waterfowl in a nearby natural area. We live-captured small birds and small mammals and collected samples from hunter-harvested waterfowl to test for active viral shedding and evidence of exposure (serum antibody) to AIV and the H5N2 HPAIV that affected the poultry facility. We detected no evidence of shedding or specific antibody to AIV in small mammals and small birds 5 mo after depopulation of the poultry. We detected viral shedding and exposure to AIV in waterfowl and estimated approximately 15% viral shedding and 60% antibody prevalence. In waterfowl, we did not detect shedding or exposure to the HPAIV that affected the poultry facility. We also conducted camera trapping around poultry carcass depopulation composting barns and found regular visitation by four species of medium-sized mammals. We provide preliminary data suggesting that peridomestic wildlife were not an important factor in the transmission of AIV during the poultry outbreak, nor did small birds and mammals in natural wetland settings show wide evidence of AIV shedding or exposure, despite the opportunity for exposure.

  10. Modeling plague transmission in Medieval European cities

    OpenAIRE

    Dean, Katharine Rose

    2015-01-01

    The Black Death pandemic swept through Europe during the Middle Ages leading to high mortality from plague, caused by the bacterium Yersinia pestis. How the disease was transmitted in Europe is not fully elucidated, and prior to the identification of the bacterium in medieval tooth samples, the nature of the pandemic led to speculation that the Black Death was not the same disease as current-day plague. In the classical mode of transmission to humans, black rats act as an intermediate host an...

  11. Impact of the plague in Ancient Greece.

    Science.gov (United States)

    Soupios, M A

    2004-03-01

    Disease as a pivotal factor in determining the course of human events may be one og the least considered historical variables. When assessing the critical junctures of history, historians seem more inclined to focus on the impact of conquering armies, economic revolutions, and technologic breakthroughs. This analysis attempts to illustrate the seminal effects of the great plague of Athens. By depleting Athenian military personnel, depriving Athens of its charismatic leadership, and dissolving the system of ideals and principles that distinguished Athens from the rest of antiquity, the plague materially altered the outcome of the Peloponnesian War, which in turn deflected the flow of all subsequent Hellenic history.

  12. Recombinant raccoon pox vaccine protects mice against lethal plague

    Science.gov (United States)

    Osorio, J.E.; Powell, T.D.; Frank, R.S.; Moss, K.; Haanes, E.J.; Smith, S.R.; Rocke, T.E.; Stinchcomb, D.T.

    2003-01-01

    Using a raccoon poxvirus (RCN) expression system, we have developed new recombinant vaccines that can protect mice against lethal plague infection. We tested the effects of a translation enhancer (EMCV-IRES) in combination with a secretory (tPA) signal or secretory (tPA) and membrane anchoring (CHV-gG) signals on in vitro antigen expression of F1 antigen in tissue culture and the induction of antibody responses and protection against Yersinia pestis challenge in mice. The RCN vector successfully expressed the F1 protein of Y. pestis in vitro. In addition, the level of expression was increased by the insertion of the EMCV-IRES and combinations of this and the secretory signal or secretory and anchoring signals. These recombinant viruses generated protective immune responses that resulted in survival of 80% of vaccinated mice upon challenge with Y. pestis. Of the RCN-based vaccines we tested, the RCN-IRES-tPA-YpF1 recombinant construct was the most efficacious. Mice vaccinated with this construct withstood challenge with as many as 1.5 million colony forming units of Y. pestis (7.7??104LD50). Interestingly, vaccination with F1 fused to the anchoring signal (RCN-IRES-tPA-YpF1-gG) elicited significant anti-F1 antibody titers, but failed to protect mice from plague challenge. Our studies demonstrate, in vitro and in vivo, the potential importance of the EMCV-IRES and secretory signals in vaccine design. These molecular tools provide a new approach for improving the efficacy of vaccines. In addition, these novel recombinant vaccines could have human, veterinary, and wildlife applications in the prevention of plague. ?? 2002 Elsevier Science Ltd. All rights reserved.

  13. Deteksi Antibodi Serum Terhadap Virus Avian influenza pada Ayam Buras

    Directory of Open Access Journals (Sweden)

    Darmawi Darmawi

    2012-04-01

    Full Text Available Detection on Serum Antibodies of Native Chickens to Avian influenza Virus ABSTRACT.  An important approach of controlling against Avian Influenza should be determined to detect the antibody titres of bird flu caused by Influenza virus H5N1 in Indonesia. The aim of the present study was to detect the antibodies to Avian Influenza in serum of native chickens. This study utilized 123 serum samples collected from the axilaris vein (left or right of native chickens. Antibody titres were examined using Hemaglutination Inhibition (HI. The result showed that indication of natural infection by Avian Influenza (H5N1 in native chickens, as shown that out of 123 serum samples, 16 (13,01% were tested positive by HI, while only 10 (8,13% were tested protective to Avian influenza infection. Based on the results we obtained, a conclusion that natural infection by Avian influenza virus stimulated variety level of formation antibody titres in native chickens.

  14. Immune Repertoire Diversity Correlated with Mortality in Avian Influenza A (H7N9) Virus Infected Patients

    Science.gov (United States)

    Hou, Dongni; Ying, Tianlei; Wang, Lili; Chen, Cuicui; Lu, Shuihua; Wang, Qin; Seeley, Eric; Xu, Jianqing; Xi, Xiuhong; Li, Tao; Liu, Jie; Tang, Xinjun; Zhang, Zhiyong; Zhou, Jian; Bai, Chunxue; Wang, Chunlin; Byrne-Steele, Miranda; Qu, Jieming; Han, Jian; Song, Yuanlin

    2016-01-01

    Specific changes in immune repertoires at genetic level responding to the lethal H7N9 virus are still poorly understood. We performed deep sequencing on the T and B cells from patients recently infected with H7N9 to explore the correlation between clinical outcomes and immune repertoire alterations. T and B cell repertoires display highly dynamic yet distinct clonotype alterations. During infection, T cell beta chain repertoire continues to contract while the diversity of immunoglobulin heavy chain repertoire recovers. Patient recovery is correlated to the diversity of T cell and B cell repertoires in different ways – higher B cell diversity and lower T cell diversity are found in survivors. The sequences clonally related to known antibodies with binding affinity to H7 hemagglutinin could be identified from survivors. These findings suggest that utilizing deep sequencing may improve prognostication during influenza infection and could help in development of antibody discovery methodologies for the treatment of virus infection. PMID:27669665

  15. 禽流感防制进展%Progress on Avian Influenza Prevention

    Institute of Scientific and Technical Information of China (English)

    赵婧; 邱小为

    2012-01-01

    Avian influenza(AI) is one of zoonoses caused by type A influenza viruse,which is also called Fowl Plague.Serious systemic symptoms of the respiratory system and other deadly infectious diseases can be caused.mortality of Infected poultry is very high,however,wild birds are not mostly dominant infected.Since 1997 Hong Kong avian influenza virus subtype H5N1 happened first breakthrough the species barrier to infect human beings and caused death,various human avian influenza cases were reported worldwide,degree of concern about human avian influenza has also reached an unprecedented level.In recent years,the global total of 19 countries on three continents and regions occurred avian influenza.The epidemic is spreading in some parts of the regions,and the emergence of human cases of avian influenza virus.Avian influenza not only causes significant damage to livestock breed industry,but also pose a serious threat to human health.Pathogens,epidemiology,clinical symptoms,pathological changes,diagnosis,prevention and treatment of Aenvian influza are discussed completely and briefly in this article.%禽流感(Avian influenza,AI)是由A型流感病毒所引起的禽类的一种传染病。能引起禽类呼吸系统到严重全身败血症等多种症状的烈性传染病。禽类感染后病死率很高,但对野生禽类多为不显性感染。自从1997年香港发生禽流感病毒H5N1亚型首次突破种属屏障感染人类并引起死亡以来,世界各国纷纷报道各种人禽流感病例的发生,人禽流感的关注程度也达到了前所未有的高度。近几年全球共有三大洲的19个国家和地区发生禽流感疫情。一些地区的疫情呈现蔓延的趋势,并且出现了人感染禽流感病毒的病例。禽流感不仅对养殖业造成重大损失,更对人类健康造成严重威胁。本文全面地介绍了禽流感的病原、流行病学、临床症状、病理变化、诊断和防制。

  16. Empirical assessment of a threshold model for sylvatic plague

    DEFF Research Database (Denmark)

    Davis, Stephen; Leirs, Herwig; Viljugrein, H.

    2007-01-01

    Plague surveillance programmes established in Kazakhstan, Central Asia, during the previous century, have generated large plague archives that have been used to parameterize an abundance threshold model for sylvatic plague in great gerbil (Rhombomys opimus) populations. Here, we assess the model...

  17. Avian influenza infection dynamics under variable climatic conditions, viral prevalence is rainfall driven in waterfowl from temperate, south-east Australia.

    Science.gov (United States)

    Ferenczi, Marta; Beckmann, Christa; Warner, Simone; Loyn, Richard; O'Riley, Kim; Wang, Xinlong; Klaassen, Marcel

    2016-02-06

    Understanding Avian Influenza Virus (AIV) infection dynamics in wildlife is crucial because of possible virus spill over to livestock and humans. Studies from the northern hemisphere have suggested several ecological and environmental drivers of AIV prevalence in wild birds. To determine if the same drivers apply in the southern hemisphere, where more irregular environmental conditions prevail, we investigated AIV prevalence in ducks in relation to biotic and abiotic factors in south-eastern Australia. We sampled duck faeces for AIV and tested for an effect of bird numbers, rainfall anomaly, temperature anomaly and long-term ENSO (El-Niño Southern Oscillation) patterns on AIV prevalence. We demonstrate a positive long term effect of ENSO-related rainfall on AIV prevalence. We also found a more immediate response to rainfall where AIV prevalence was positively related to rainfall in the preceding 3-7 months. Additionally, for one duck species we found a positive relationship between their numbers and AIV prevalence, while prevalence was negatively or not affected by duck numbers in the remaining four species studied. In Australia largely non-seasonal rainfall patterns determine breeding opportunities and thereby influence bird numbers. Based on our findings we suggest that rainfall influences age structures within populations, producing an influx of immunologically naïve juveniles within the population, which may subsequently affect AIV infection dynamics. Our study suggests that drivers of AIV dynamics in the northern hemisphere do not have the same influence at our south-east Australian field site in the southern hemisphere due to more erratic climatological conditions.

  18. Human microRNA-24 modulates highly pathogenic avian-origin H5N1 influenza A virus infection in A549 cells by targeting secretory pathway furin.

    Science.gov (United States)

    Loveday, Emma-Kate; Diederich, Sandra; Pasick, John; Jean, François

    2015-01-01

    A common critical cellular event that many human enveloped viruses share is the requirement for proteolytic cleavage of the viral glycoprotein by furin in the host secretory pathway. For example, the furin-dependent proteolytic activation of highly pathogenic (HP) influenza A (infA) H5 and H7 haemagglutinin precursor (HA0) subtypes is critical for yielding fusion-competent infectious virions. In this study, we hypothesized that viral hijacking of the furin pathway by HP infA viruses to permit cleavage of HA0 could represent a novel molecular mechanism controlling the dynamic production of fusion-competent infectious virus particles during the viral life cycle. We explored the biological role of a newly identified furin-directed human microRNA, miR-24, in this process as a potential post-transcriptional regulator of the furin-mediated activation of HA0 and production of fusion-competent virions in the host secretory pathway. We report that miR-24 and furin are differentially expressed in human A549 cells infected with HP avian-origin infA H5N1. Using miR-24 mimics, we demonstrated a robust decrease in both furin mRNA levels and intracellular furin activity in A549 cells. Importantly, pretreatment of A549 cells with miR-24 mimicked these results: a robust decrease of H5N1 infectious virions and a complete block of H5N1 virus spread that was not observed in A549 cells infected with low-pathogenicity swine-origin infA H1N1 virus. Our results suggest that viral-specific downregulation of furin-directed microRNAs such as miR-24 during the life cycle of HP infA viruses may represent a novel regulatory mechanism that governs furin-mediated proteolytic activation of HA0 glycoproteins and production of infectious virions.

  19. Saving Resources with Plagues in Genetic Algorithms

    Energy Technology Data Exchange (ETDEWEB)

    de Vega, F F; Cantu-Paz, E; Lopez, J I; Manzano, T

    2004-06-15

    The population size of genetic algorithms (GAs) affects the quality of the solutions and the time required to find them. While progress has been made in estimating the population sizes required to reach a desired solution quality for certain problems, in practice the sizing of populations is still usually performed by trial and error. These trials might lead to find a population that is large enough to reach a satisfactory solution, but there may still be opportunities to optimize the computational cost by reducing the size of the population. This paper presents a technique called plague that periodically removes a number of individuals from the population as the GA executes. Recently, the usefulness of the plague has been demonstrated for genetic programming. The objective of this paper is to extend the study of plagues to genetic algorithms. We experiment with deceptive trap functions, a tunable difficult problem for GAs, and the experiments show that plagues can save computational time while maintaining solution quality and reliability.

  20. Induction of inflammatory cytokines and toll-like receptors in chickens infected with avian H9N2 influenza virus

    Directory of Open Access Journals (Sweden)

    Nang Nguyen

    2011-05-01

    Full Text Available Abstract H9N2 influenza virus is endemic in many Asian countries and is regarded as a candidate for the next human pandemic. Knowledge of the induction of inflammatory responses and toll-like receptors (TLRs in chickens infected with H9N2 is limited. Here, we show that H9N2 induces pro-inflammatory cytokines such as transforming growth factor-beta 3; tumor necrosis factor-alpha; interferon-alpha, -beta, and gamma; and TLR 1, 2, 3, 4, 5, 7, and 15 in trachea, lung, and intestine of infected chickens. In the lung, TLR-15 was dominantly induced. Taken together, it seems that H9N2 infections efficiently induce inflammatory cytokines and TLRs in trachea, lung and intestine of chickens.

  1. Study on the Basic Plague Pattern of Jianchuan Plague Natural Focus, Yunnan Province, China

    Institute of Scientific and Technical Information of China (English)

    TIAN Jie

    2001-01-01

    Since the plague natural focus of Jianchuan was found in 1974, it had broken the disputation whether Yunnan has plague natural focus among Chinese and foreign scholars for long. Because the focus locates the middle part of transversal mountains with higher biological diversity and complex landscape, many problems raised at beginning in distinguishing the major hosts and vectors, modeling the structure of the focus, and resolving the contradiction between theory and excitation. In review of that, according to the principle of unified of biological structure and function, the basic plague pattern has been systematically studied on through the generalized information concept in this paper. It suggests that the focus takes the community of Apodemus chevrieri + Rattus norvegicus : Neopsylla specialis + Frontopsylla. spadix + Menopsyllus anisus + Loptopsylla segnis as maintenance subsystem, the community of E. miletus:Ctenophthalmus quadratus + Neopsylla specialis as epidematic (amplifying) subsystem, the communities of squirrel rodent-flea as alternate subsystem. The relationship between subsystems is nonlinear. No human plague case is determined by the systematicness of the plague ecosystem. The possibility of human plague will remain in systemic changing or coming into chaos. Although most researches try to analysis of plague as system by means of experiments with many quantitative criterion, these measures are difficult to comprehension the systemic essence without application of the concept of systemic theory. They are often direct, discursive and paradoxical description of appearance rather than the analysis and generalization of interaction relationship between elements, thus reversing the basic ecological concept of Y.pestis as a living thing and agent of plague.

  2. Distribution of sialic acid receptors and influenza A viruses of avian and swine origin and in experimentally infected pigs

    DEFF Research Database (Denmark)

    Trebbien, Ramona; Larsen, Lars Erik; Viuff, Birgitte M.

    2011-01-01

    antigen was widely distributed in bronchi, but was also present in epithelial cells of the nose, trachea, bronchioles, and alveolar type I and II epithelial cells in severely affected animals. AIV was found in the lower respiratory tract, especially in alveolar type II epithelial cells and occasionally...... amounts in bronchioles, and in alveoli reaching an average of 20-40% at the epithelial cells. Interestingly, the receptor expression of both SA-alpha-2,3 and 2,6 was markedly diminished in influenza infected areas compared to non-infected areas. Conclusions: A difference in predilection sites between SIV...

  3. New Insights into How Yersinia pestis Adapts to Its Mammalian Host during Bubonic Plague

    Science.gov (United States)

    Pradel, Elizabeth; Lemaître, Nadine; Merchez, Maud; Ricard, Isabelle; Reboul, Angéline; Dewitte, Amélie; Sebbane, Florent

    2014-01-01

    Bubonic plague (a fatal, flea-transmitted disease) remains an international public health concern. Although our understanding of the pathogenesis of bubonic plague has improved significantly over the last few decades, researchers have still not been able to define the complete set of Y. pestis genes needed for disease or to characterize the mechanisms that enable infection. Here, we generated a library of Y. pestis mutants, each lacking one or more of the genes previously identified as being up-regulated in vivo. We then screened the library for attenuated virulence in rodent models of bubonic plague. Importantly, we tested mutants both individually and using a novel, “per-pool” screening method that we have developed. Our data showed that in addition to genes involved in physiological adaption and resistance to the stress generated by the host, several previously uncharacterized genes are required for virulence. One of these genes (ympt1.66c, which encodes a putative helicase) has been acquired by horizontal gene transfer. Deletion of ympt1.66c reduced Y. pestis' ability to spread to the lymph nodes draining the dermal inoculation site – probably because loss of this gene decreased the bacteria's ability to survive inside macrophages. Our results suggest that (i) intracellular survival during the early stage of infection is important for plague and (ii) horizontal gene transfer was crucial in the acquisition of this ability. PMID:24675805

  4. New insights into how Yersinia pestis adapts to its mammalian host during bubonic plague.

    Directory of Open Access Journals (Sweden)

    Elizabeth Pradel

    2014-03-01

    Full Text Available Bubonic plague (a fatal, flea-transmitted disease remains an international public health concern. Although our understanding of the pathogenesis of bubonic plague has improved significantly over the last few decades, researchers have still not been able to define the complete set of Y. pestis genes needed for disease or to characterize the mechanisms that enable infection. Here, we generated a library of Y. pestis mutants, each lacking one or more of the genes previously identified as being up-regulated in vivo. We then screened the library for attenuated virulence in rodent models of bubonic plague. Importantly, we tested mutants both individually and using a novel, "per-pool" screening method that we have developed. Our data showed that in addition to genes involved in physiological adaptation and resistance to the stress generated by the host, several previously uncharacterized genes are required for virulence. One of these genes (ympt1.66c, which encodes a putative helicase has been acquired by horizontal gene transfer. Deletion of ympt1.66c reduced Y. pestis' ability to spread to the lymph nodes draining the dermal inoculation site--probably because loss of this gene decreased the bacteria's ability to survive inside macrophages. Our results suggest that (i intracellular survival during the early stage of infection is important for plague and (ii horizontal gene transfer was crucial in the acquisition of this ability.

  5. The PSAP motif within the ORF3 protein of an avian strain of the hepatitis E virus is not critical for viral infectivity in vivo but plays a role in virus release.

    Science.gov (United States)

    Kenney, Scott P; Pudupakam, R S; Huang, Yao-Wei; Pierson, F William; LeRoith, Tanya; Meng, Xiang-Jin

    2012-05-01

    The ORF3 protein of hepatitis E virus (HEV) is a multifunctional protein important for virus replication. The ORF3 proteins from human, swine, and avian strains of HEV contain a conserved PXXP amino acid motif, resembling either Src homology 3 (SH3) cell signaling interaction motifs or "late domains" involved in host cell interactions aiding in particle release. Using an avian strain of HEV, we determined the roles of the conserved prolines within the PREPSAPP motif in HEV replication and infectivity in Leghorn male hepatoma (LMH) chicken liver cells and in chickens. Each proline was changed to alanine to produce 8 avian HEV mutants containing single mutations (P64, P67, P70, and P71 to A), double mutations (P64/67A, P64/70A, and P67/70A), and triple mutations (P64/67/70A). The results showed that avian HEV mutants are replication competent in vitro, and none of the prolines in the PXXPXXPP motif are essential for infectivity in vivo; however, the second and third prolines appear to aid in fecal virus shedding, suggesting that the PSAP motif, but not the PREP motif, is involved in virus release. We also showed that the PSAP motif interacts with the host protein tumor suppressor gene 101 (TSG101) and that altering any proline within the PSAP motif disrupts this interaction. However, we showed that the ORF2 protein expressed in LMH cells is efficiently released from the cells in the absence of ORF3 and that coexpression of ORF2 and ORF3 did not act synergistically in this release, suggesting that another factor(s) such as ORF1 or viral genomic RNA may be necessary for proper particle release.

  6. Resistance to plague among black-tailed prairie dog populations.

    Science.gov (United States)

    Rocke, Tonie E; Williamson, Judy; Cobble, Kacy R; Busch, Joseph D; Antolin, Michael F; Wagner, David M

    2012-02-01

    In some rodent species frequently exposed to plague outbreaks caused by Yersinia pestis, resistance to the disease has evolved as a population trait. As a first step in determining if plague resistance has developed in black-tailed prairie dogs (Cynomys ludovicianus), animals captured from colonies in a plague-free region (South Dakota) and two plague-endemic regions (Colorado and Texas) were challenged with Y. pestis at one of three doses (2.5, 250, or 2500 mouse LD50s). South Dakota prairie dogs were far more susceptible to plague than Colorado and Texas prairie dogs (pplague resistance.

  7. Age at vaccination may influence response to sylvatic plague vaccine (SPV) in Gunnison’s prairie dogs (Cynomys gunnisoni)

    Science.gov (United States)

    Rocke, Tonie E.; Tripp, Daniel W.; Lorenzsonn, Faye; Falendysz, Elizabeth A.; Smith, Susan; Williamson, Judy L.; Abbott, Rachel C.

    2015-01-01

    Gunnison’s prairie dogs (Cynomys gunnisoni) have been considered at greater risk from Yersinia pestis (plague) infection in the montane portion of their range compared to populations at lower elevations, possibly due to factors related to flea transmission of the bacteria or greater host susceptibility. To test the latter hypothesis and determine whether vaccination against plague with an oral sylvatic plague vaccine (SPV) improved survival, we captured prairie dogs from a C. g. gunnisoni or “montane” population and a C. g. zuniensis or “prairie” population for vaccine efficacy and challenge studies. No differences (P = 0.63) were found in plague susceptibility in non-vaccinated animals between these two populations; however, vaccinates from the prairie population survived plague challenge at significantly higher rates (P dogs, and that SPV could be a useful plague management tool for this species, particularly if targeted at younger cohorts.

  8. Impact of the Pla protease substrate α2-antiplasmin on the progression of primary pneumonic plague.

    Science.gov (United States)

    Eddy, Justin L; Schroeder, Jay A; Zimbler, Daniel L; Bellows, Lauren E; Lathem, Wyndham W

    2015-12-01

    Many pathogens usurp the host hemostatic system during infection to promote pathogenesis. Yersinia pestis, the causative agent of plague, expresses the plasminogen activator protease Pla, which has been shown in vitro to target and cleave multiple proteins within the fibrinolytic pathway, including the plasmin inhibitor α2-antiplasmin (A2AP). It is not known, however, if Pla inactivates A2AP in vivo; the role of A2AP during respiratory Y. pestis infection is not known either. Here, we show that Y. pestis does not appreciably cleave A2AP in a Pla-dependent manner in the lungs during experimental pneumonic plague. Furthermore, following intranasal infection with Y. pestis, A2AP-deficient mice exhibit no difference in survival time, bacterial burden in the lungs, or dissemination from wild-type mice. Instead, we found that in the absence of Pla, A2AP contributes to the control of the pulmonary inflammatory response during infection by reducing neutrophil recruitment and cytokine production, resulting in altered immunopathology of the lungs compared to A2AP-deficient mice. Thus, our data demonstrate that A2AP is not significantly affected by the Pla protease during pneumonic plague, and although A2AP participates in immune modulation in the lungs, it has limited impact on the course or ultimate outcome of the infection.

  9. Thinking extreme social violence: the model of the literary plague.

    Science.gov (United States)

    Priel, Beatriz

    2007-12-01

    The author uses literary plagues as a model for thinking psychoanalytically about the basic anxieties activated among perpetrators of sanctioned massacres. The model of the plague allows abstracting an underlying primitive psychological organization characterized by syncretism and a powerful anxiety of de-differentiation and confusion, leading characteristically to imitative behavior within the in-group as well as to the disavowal of the out-group members similarities to oneself, i.e. the disavowal of the other's humanity. Recognizing the historical and social foundations of discrimination and genocide, the author analyzes the interaction between group and individual processes that allow ordinary people to join daily acts of immoral violence. She dramatizes the model of the plague through a psychoanalytic reading of three literary plagues: Thebes' plague according to Sophocles, Camus's chronicle of the plague in Oran, and Saramago's meditation on the plague of white blindness.

  10. Hypothesis on the source, transmission and characteristics of infection of avian influenza A (H7N9) virus--based on analysis of field epidemiological investigation and gene sequence analysis.

    Science.gov (United States)

    Ling, F; Chen, E; Liu, Q; Miao, Z; Gong, Z

    2015-02-01

    On 31 March 2013, the National Health and Family Planning Commission announced that human infections with influenza A (H7N9) virus had occurred in Shanghai and Anhui provinces, China. H7N9 cases were later detected in Jiangsu and Zhejiang provinces. It was estimated that the virus first spread northward along the route taken by migratory birds and then spread to neighbouring provinces with the sale of poultry. Epidemiological studies were carried out on samples from the external environment of infected cases, transmission routes, farmers markets and live poultry markets. Phylogenetic study of viral sequences from human and avian infections in Zhejiang showed that those from Shanghai and Jiangsu provinces along Taihu Lake were highly homologous with those from the external environment. This suggests that avian viruses carried by waterfowl combined with the virus carried by migratory birds, giving rise to avian influenza virus H7N9, which is highly pathogenic to humans. It is possible that the virus was transmitted by local wildfowl to domestic poultry and then to humans, or spread further by means of trading in wholesale poultry markets. As the weather has turned warm, and with measures adopted to terminate poultry trade and facilitate health communication, the epidemic in the first half of the year has been kept under control. However, the infection source in the triangular area around Taihu Lake still remains. The H7N9 epidemic will probably hit the area later in the year and next spring when the migratory birds return and may even spread to other areas. Great importance should therefore be attached to the wildfowl in Taihu Lake as the repository and disseminator of the virus: investigation and study of this population is essential.

  11. Depressed Hypoxic and Hypercapnic Ventilatory Responses at Early Stage of Lethal Avian Influenza A Virus Infection in Mice.

    Directory of Open Access Journals (Sweden)

    Jianguo Zhuang

    Full Text Available H5N1 virus infection results in ~60% mortality in patients primarily due to respiratory failure, but the underlying causes of mortality are unclear. The goal of this study is to reveal respiratory disorders occurring at the early stage of infection that may be responsible for subsequent respiratory failure and death. BALB/c mice were intranasally infected with one of two H5N1 virus strains: HK483 (lethal or HK486 (non-lethal virus. Pulmonary ventilation and the responses to hypoxia (HVR; 7% O2 for 3 min and hypercapnia (HCVR; 7% CO2 for 5 min were measured daily at 2 days prior and 1, 2, and 3 days postinfection (dpi and compared to mortality typically by 8 dpi. At 1, 2, and 3 dpi, immunoreactivities (IR of substance P (SP-IR in the nodose ganglion or tyrosine hydroxylase (TH-IR in the carotid body coupled with the nucleoprotein of influenza A (NP-IR was examined in some mice, while arterial blood was collected in others. Our results showed that at 2 and 3 dpi: 1 both viral infections failed to alter body temperature and weight, [Formula: see text], or induce viremia while producing similarly high lung viral titers; 2 HK483, but not HK486, virus induced tachypnea and depressed HVR and HCVR without changes in arterial blood pH and gases; and 3 only HK483 virus led to NP-IR in vagal SP-IR neurons, but not in the carotid body, and increased density of vagal SP-IR neurons. In addition, all HK483, rather than HK486, mice died at 6 to 8 dpi and the earlier death was correlated with more severe depression of HVR and HCVR. Our data suggest that tachypnea and depressed HVR/HCVR occur at the early stage of lethal H5N1 viral infection associated with viral replication and increased SP-IR density in vagal neurons, which may contribute to the respiratory failure and death.

  12. Ecology and conservation biology of avian malaria

    Science.gov (United States)

    LaPointe, Dennis A.; Atkinson, Carter T.; Samuel, Michael D.

    2012-01-01

    Avian malaria is a worldwide mosquito-borne disease caused by Plasmodium parasites. These parasites occur in many avian species but primarily affect passerine birds that have not evolved with the parasite. Host pathogenicity, fitness, and population impacts are poorly understood. In contrast to continental species, introduced avian malaria poses a substantial threat to naive birds on Hawaii, the Galapagos, and other archipelagoes. In Hawaii, transmission is maintained by susceptible native birds, competence and abundance of mosquitoes, and a disease reservoir of chronically infected native birds. Although vector habitat and avian communities determine the geographic distribution of disease, climate drives transmission patterns ranging from continuous high infection in warm lowland forests, seasonal infection in midelevation forests, and disease-free refugia in cool high-elevation forests. Global warming is expected to increase the occurrence, distribution, and intensity of avian malaria across this elevational gradient and threaten high-elevation refugia, which is the key to survival of many susceptible Hawaiian birds. Increased temperatures may have already increased global avian malaria prevalence and contributed to an emergence of disease in New Zealand.

  13. Avian malaria in New Zealand.

    Science.gov (United States)

    Schoener, E R; Banda, M; Howe, L; Castro, I C; Alley, M R

    2014-07-01

    Avian malaria parasites of the genus Plasmodium have the ability to cause morbidity and mortality in naïve hosts, and their impact on the native biodiversity is potentially serious. Over the last decade, avian malaria has aroused increasing interest as an emerging disease in New Zealand with some endemic avian species, such as the endangered mohua (Mohua ochrocephala), thought to be particularly susceptible. To date, avian malaria parasites have been found in 35 different bird species in New Zealand and have been diagnosed as causing death in threatened species such as dotterel (Charadrius obscurus), South Island saddleback (Philesturnus carunculatus carunculatus), mohua, hihi (Notiomystis cincta) and two species of kiwi (Apteryx spp.). Introduced blackbirds (Turdus merula) have been found to be carriers of at least three strains of Plasmodium spp. and because they are very commonly infected, they are likely sources of infection for many of New Zealand's endemic birds. The spread and abundance of introduced and endemic mosquitoes as the result of climate change is also likely to be an important factor in the high prevalence of infection in some regions and at certain times of the year. Although still limited, there is a growing understanding of the ecology and epidemiology of Plasmodium spp. in New Zealand. Molecular biology has played an important part in this process and has markedly improved our understanding of the taxonomy of the genus Plasmodium. This review presents our current state of knowledge, discusses the possible infection and disease outcomes, the implications for host behaviour and reproduction, methods of diagnosis of infection, and the possible vectors for transmission of the disease in New Zealand.

  14. Serum levels of mannan-binding lectin in chickens prior to and during experimental infection with avian infectious bronchitis virus

    DEFF Research Database (Denmark)

    Juul-Madsen, H.R.; Munch, M.; Handberg, Kurt;

    2003-01-01

    Mannan-binding lectin (MBL) is a glycoprotein and a member of the C-type lectin super family, the collectin family, and the acute phase protein family. The MBL exerts its function by directly binding to microbial surfaces through its carbohydrate recognition domains, followed by direct opsonization...... that the acute phase MBL response to infection with IBV was, to a degree (P ...%, whereas the acute phase response in chickens challenged after 12 h of rest peaked after 3.1 d with an increase of 51%. The specific antibody titer against IBV was also tested, and a difference (P

  15. Heterogeneity and Seroprevalence of a Newly Identified Avian Hepatitis E Virus from Chickens in the United States

    OpenAIRE

    Huang, F. F.; Haqshenas, G.; Shivaprasad, H L; Guenette, D. K.; Woolcock, P. R.; Larsen, C. T.; Pierson, F.W.; F Elvinger; Toth, T. E.; Meng, X. J.

    2002-01-01

    We recently identified and characterized a novel virus, designated avian hepatitis E virus (avian HEV), from chickens with hepatitis-splenomegaly syndrome (HS syndrome) in the United States. Avian HEV is genetically related to but distinct from human and swine HEVs. To determine the extent of genetic variation and the seroprevalence of avian HEV infection in chicken flocks, we genetically identified and characterized 11 additional avian HEV isolates from chickens with HS syndrome and assessed...

  16. Bubonic plague: a metapopulation model of a zoonosis.

    Science.gov (United States)

    Keeling, M J; Gilligan, C A

    2000-01-01

    Bubonic plague (Yersinia pestis) is generally thought of as a historical disease; however, it is still responsible for around 1000-3000 deaths each year worldwide. This paper expands the analysis of a model for bubonic plague that encompasses the disease dynamics in rat, flea and human populations. Some key variables of the deterministic model, including the force of infection to humans, are shown to be robust to changes in the basic parameters, although variation in the flea searching efficiency, and the movement rates of rats and fleas will be considered throughout the paper. The stochastic behaviour of the corresponding metapopulation model is discussed, with attention focused on the dynamics of rats and the force of infection at the local spatial scale. Short-lived local epidemics in rats govern the invasion of the disease and produce an irregular pattern of human cases similar to those observed. However, the endemic behaviour in a few rat subpopulations allows the disease to persist for many years. This spatial stochastic model is also used to identify the criteria for the spread to human populations in terms of the rat density. Finally, the full stochastic model is reduced to the form of a probabilistic cellular automaton, which allows the analysis of a large number of replicated epidemics in large populations. This simplified model enables us to analyse the spatial properties of rat epidemics and the effects of movement rates, and also to test whether the emergent metapopulation behaviour is a property of the local dynamics rather than the precise details of the model. PMID:11413636

  17. Exposure of small rodents to plague during epizootics in black-tailed prairie dogs.

    Science.gov (United States)

    Stapp, Paul; Salkeld, Daniel J; Eisen, Rebecca J; Pappert, Ryan; Young, John; Carter, Leon G; Gage, Kenneth L; Tripp, Daniel W; Antolin, Michael F

    2008-07-01

    Plague, caused by the bacterium Yersinia pestis, causes die-offs of colonies of prairie dogs (Cynomys ludovicianus). It has been argued that other small rodents are reservoirs for plague, spreading disease during epizootics and maintaining the pathogen in the absence of prairie dogs; yet there is little empirical support for distinct enzootic and epizootic cycles. Between 2004 and 2006, we collected blood from small rodents captured in colonies in northern Colorado before, during, and for up to 2 yr after prairie dog epizootics. We screened 1,603 blood samples for antibodies to Y. pestis, using passive hemagglutination and inhibition tests, and for a subset of samples we cultured blood for the bacterium itself. Of the four species of rodents that were common in colonies, the northern grasshopper mouse (Onychomys leucogaster) was the only species with consistent evidence of plague infection during epizootics, with 11.1-23.1% of mice seropositive for antibody to Y. pestis during these events. Seropositive grasshopper mice, thirteen-lined ground squirrels (Spermophilus tridecemlineatus), and deer mice (Peromyscus maniculatus) were captured the year following epizootics. The appearance of antibodies to Y. pestis in grasshopper mice coincided with periods of high prairie dog mortality; subsequently, antibody prevalence rates declined, with no seropositive individuals captured 2 yr after epizootics. We did not detect plague in any rodents off of colonies, or on colonies prior to epizootics, and found no evidence of persistent Y. pestis infection in blood cultures. Our results suggest that grasshopper mice could be involved in epizootic spread of Y. pestis, and possibly, serve as a short-term reservoir for plague, but provide no evidence that the grasshopper mouse or any small rodent acts as a long-term, enzootic host for Y. pestis in prairie dog colonies.

  18. First evidence of crayfish plague agent in populations of the marbled crayfish (Procambarus fallax forma virginalis

    Directory of Open Access Journals (Sweden)

    Keller N.S.

    2014-01-01

    Full Text Available The introduction of non-indigenous species and associated diseases can cause declines in indigenous flora and fauna and threaten local biodiversity. The crayfish plague pathogen (Aphanomyces astaci, carried and transmitted by latent infected North American crayfish, can lead to high mortalities in indigenous European crayfish populations. Although the parthenogenetic marbled crayfish (Procambarus fallax (Hagen, 1870  forma virginalis is common in the aquarium trade and has established wild populations in Europe, its carrier status is still unknown. This study investigated one captive and three established wild-living marbled crayfish populations for an infection with the crayfish plague pathogen applying real-time PCR. We demonstrate that captive, as well as two wild marbled crayfish populations were infected by A. astaci. Although infection status in laboratory kept specimens reached high levels, marbled crayfish showed no obviously plague-related mortality. Furthermore, sequence analysis revealed that captive crayfish carried the A. astaci genotype Pc, which has earlier been isolated from the North American red swamp crayfish (Procambarus clarkii. The results indicate that due to its positive carrier status marbled crayfish poses a greater threat to local biodiversity in Europe than considered until now.

  19. Flea diversity as an element for persistence of plague bacteria in an East African plague focus.

    Directory of Open Access Journals (Sweden)

    Rebecca J Eisen

    Full Text Available Plague is a flea-borne rodent-associated zoonotic disease that is caused by Yersinia pestis and characterized by long quiescent periods punctuated by rapidly spreading epidemics and epizootics. How plague bacteria persist during inter-epizootic periods is poorly understood, yet is important for predicting when and where epizootics are likely to occur and for designing interventions aimed at local elimination of the pathogen. Existing hypotheses of how Y. pestis is maintained within plague foci typically center on host abundance or diversity, but little attention has been paid to the importance of flea diversity in enzootic maintenance. Our study compares host and flea abundance and diversity along an elevation gradient that spans from low elevation sites outside of a plague focus in the West Nile region of Uganda (~725-1160 m to higher elevation sites within the focus (~1380-1630 m. Based on a year of sampling, we showed that host abundance and diversity, as well as total flea abundance on hosts was similar between sites inside compared with outside the plague focus. By contrast, flea diversity was significantly higher inside the focus than outside. Our study highlights the importance of considering flea diversity in models of Y. pestis persistence.

  20. War, plague and exploitation in DR Congo

    Directory of Open Access Journals (Sweden)

    Dimčevska Antoaneta K.

    2007-01-01

    Full Text Available Late in autumn 2006 one of the headlines in world media was the first democratic elections in DR Congo. They took place after 30 years of Mobutu Sese Seko’s dictatorship and bloody civil wars in the period 1996-2002. These conflicts, which took approximately 4 million human lives, are called "The First African World War". Elections were held but they did not guarantee the end of trouble for the divided and tormented people in the northeast of Congo, the real scene of bloodshed. The area is still turbulent because it abounds in mineral wealth - gold, diamonds and raw materials for nuclear technology. For a whole decade, unscrupulous actors of the African crisis were fighting there, for illegal profits (achievable in the chaos of bloodshed rather than for democracy, defense of tribal interests, security, etc. as they claimed. In the mines of Eastern Congo unprecedented exploitation of people is still going on, especially of children, victims of conflicts, who suffer in great numbers from violence, starvation and diseases. These slaves of the crisis make local "warlords" and their mentors rich. The looting of the mines has stabilized the crisis because it makes possible enormous accumulation of wealth among armed decision-makers - which also includes availability of countless slaves-miners who have lost everything except their bare lives. Eastern Congo is, however, one of world’s three old focuses of plague; wild exploitation of ores in the area of this endemic disease has activated a sleepy focus and added pneumonic plague to the burdens suffered by the population of the rich but ill-fated region. This was to be expected because endemic plague in the gold-bearing evil circumstances impedes safe mining - and this will be the crucial challenge in the future of Congo. This article is an anthropological outline of the area where gold, plague, weapons and incomparable suffering of people merge together just because of cynic greed producing abuse

  1. Recent results on the spatiotemporal modelling and comparative analysis of Black Death and bubonic plague epidemics

    Science.gov (United States)

    Christakos, G.; Olea, R.A.; Yu, H.-L.

    2007-01-01

    Background: This work demonstrates the importance of spatiotemporal stochastic modelling in constructing maps of major epidemics from fragmentary information, assessing population impacts, searching for possible etiologies, and performing comparative analysis of epidemics. Methods: Based on the theory previously published by the authors and incorporating new knowledge bases, informative maps of the composite space-time distributions were generated for important characteristics of two major epidemics: Black Death (14th century Western Europe) and bubonic plague (19th-20th century Indian subcontinent). Results: The comparative spatiotemporal analysis of the epidemics led to a number of interesting findings: (1) the two epidemics exhibited certain differences in their spatiotemporal characteristics (correlation structures, trends, occurrence patterns and propagation speeds) that need to be explained by means of an interdisciplinary effort; (2) geographical epidemic indicators confirmed in a rigorous quantitative manner the partial findings of isolated reports and time series that Black Death mortality was two orders of magnitude higher than that of bubonic plague; (3) modern bubonic plague is a rural disease hitting harder the small villages in the countryside whereas Black Death was a devastating epidemic that indiscriminately attacked large urban centres and the countryside, and while the epidemic in India lasted uninterruptedly for five decades, in Western Europe it lasted three and a half years; (4) the epidemics had reverse areal extension features in response to annual seasonal variations. Temperature increase at the end of winter led to an expansion of infected geographical area for Black Death and a reduction for bubonic plague, reaching a climax at the end of spring when the infected area in Western Europe was always larger than in India. Conversely, without exception, the infected area during winter was larger for the Indian bubonic plague; (5) during the

  2. [Detection and description of avian hepatitis E virus isolated in China--a review].

    Science.gov (United States)

    Zhao, Qin; Sun, Yani; Zhou, Enmin

    2012-03-04

    Avian hepatitis E virus (HEV), a member of Hepeviridae family, is genetically and antigenically related with human and swine HEV in the family. Since its discovery, avian HEV infection has been investigated in many countries from serology and molecular epidemiology studies. At present, five complete or near complete genomes of avian HEV isolates were reported in GenBank and were divided into three genotypes. The complete genome of avian HEV contains 3 ORFs of which ORF2 gene encodes capsid protein containing the primary epitopes of viral particles and is target gene for serodiagnostic antigen and vaccine candidate. Because avian HEV infection has significant impact on the poultry industry and potential zoonotic transmission, the researches on avian HEV have been given much attention. We here give a broad review of the research update on the aetiology, pathogenesis and the antigenicity of capsid protein of avian HEV based on identification of Chinese avian HEV isolate.

  3. Poultry-handling Practices during Avian Influenza Outbreak, Thailand

    OpenAIRE

    Sonja J Olsen; Laosiritaworn, Yongjua; Pattanasin, Sarika; Prapasiri, Prabda; Scott F Dowell

    2005-01-01

    With poultry outbreaks of avian influenza H5N1 continuing in Thailand, preventing human infection remains a priority. We surveyed residents of rural Thailand regarding avian influenza knowledge, attitudes, and practices. Results suggest that public education campaigns have been effective in reaching those at greatest risk, although some high-risk behavior continues.

  4. Avian polyomavirus infection of a fledgling budgerigar (Melopsittacus undulatus) and differential diagnoses of viral inclusions in psittacine birds--case report and mini-review.

    Science.gov (United States)

    Herder, Vanessa; König, Anett; Seehusen, Frauke; Wohlsein, Peter

    2011-01-01

    A two-week-old budgerigar (Melopsittacus undulatus) of an outdoor aviary died suddenly and was submitted for determination the cause of illness and death. Macroscopically, the sparsely feathered animal was in a poor body condition. Histopathological examination revealed in various mesenchymal and epithelial tissues, numerous up to 15 microm in diameter large intranuclear, amphophilic to basophilic inclusion bodies with a clearing of the centre. Additionally, a feather dysplasia and retention hyperkeratosis of feather follicles was found. Ultrastructurally, viral particles of approximately 35 nm in diameter were detected in the feather follicle epithelium. A PCR for Avian Polyomavirus on fresh skin samples was negative whereas on formalin-fixed kidney samples with a high amount of viral inclusion bodies yielded a positive result. In addition, viral inclusion body diseases, like Avian Poxvirus, Psittacine Beak and Feather disease virus, Avian Adenovirus, Psittacine Herpesvirus and papillomavirus of psittacines are summarized and compared in the present article.

  5. Scientific understanding of avian influenza A H7N9 virus to effectively prevent and control of its infection%科学认识H7N9,有效防控人感染禽流感病毒

    Institute of Scientific and Technical Information of China (English)

    毛青

    2013-01-01

    On March 31, 2013, the Centers for Disease Control and Prevention of China first reported 3 laboratory confirmed cases of human infection with influenza A subtype H7N9 virus, a new avian influenza virus (AIV) in the eastern China. Up to April 15, 2013, a total of 63 cases of laboratory confirmed infection have been reported. Most reported cases have severe respiratory illness, and 14 of them died since February. Scientists of China have found that the influenza A( H7N9) virus was derived from a reassortment of 3 strains of AIV, and substantial mutations have been detected. Compared to seasonal influenza, the susceptibility of human to influenza A(H7N9) virus is low, but some cases are likely to become virus carriers or recessive infection. No person-to-person transmission of the influenza A( H7N9) virus has been found, and the reported cases are not linked to each other. Currently, there is no vaccine or effective treatment available for H7N9 infection, thus, strengthening prevention strategy is critical to avoid being infected. The article aims at discussing the clinic features of the infection of the influenza A( H7N9) virus and recommending some precautionary measures to prevent the infection.

  6. 人感染高致病性禽流感A/H5N1研究现状%Current opinions in highly pathogenic avian influenza A/HSN1 infection in human being

    Institute of Scientific and Technical Information of China (English)

    李佳; 高占成

    2009-01-01

    The avian influenza virus A/HSN1, known to infect only birds previously, broke the species-interface to infect human beings in Hong Kong in 1997. In the 21st century,highly pathogenic avian influenza viruse A/H5N1 is unprecedently spreading to the continents of Asia, Middle East and Africa, involving 15 countries. The mortality is over 60% and this incidence raises universally,concerning about the possibility that such an influenza virus might become the next influenza pandemic strain. This review summarizes the current opinions of avian influenza A/H5N1 with emphasis on virology, epidemiology, pathology and pathogenesis.%1997年,在香港发生禽流感病毒A/HSNl首次突破种间屏障感染人类的病例.21世纪以来,A/HSN1亚型高致病性禽流感疫情的传播范围、规模以及蔓延速度达到了前所未有的程度.世界上许多国家受到冲击,世界范围内病死率超过60%.鉴于目前全球可能出现新一次流感大流行的严峻形势,加强人禽流感的研究迫在眉睫.本文就人禽流感的病毒研究、流行病学特征、病理改变、发病机制等方面进展进行简要综述.

  7. Disease limits populations: plague and black-tailed prairie dogs.

    Science.gov (United States)

    Cully, Jack F; Johnson, Tammi L; Collinge, Sharon K; Ray, Chris

    2010-01-01

    Plague is an exotic vector-borne disease caused by the bacterium Yersinia pestis that causes mortality rates approaching 100% in black-tailed prairie dogs (Cynomys ludovicianus). We mapped the perimeter of the active portions of black-tailed prairie dog colonies annually between 1999 and 2005 at four prairie dog colony complexes in areas with a history of plague, as well as at two complexes that were located outside the distribution of plague at the time of mapping and had therefore never been affected by the disease. We hypothesized that the presence of plague would significantly reduce overall black-tailed prairie dog colony area, reduce the sizes of colonies on these landscapes, and increase nearest-neighbor distances between colonies. Within the region historically affected by plague, individual colonies were smaller, nearest-neighbor distances were greater, and the proportion of potential habitat occupied by active prairie dog colonies was smaller than at plague-free sites. Populations that endured plague were composed of fewer large colonies (>100 ha) than populations that were historically plague free. We suggest that these differences among sites in colony size and isolation may slow recolonization after extirpation. At the same time, greater intercolony distances may also reduce intercolony transmission of pathogens. Reduced transmission among smaller and more distant colonies may ultimately enhance long-term prairie dog population persistence in areas where plague is present.

  8. Disease limits populations: plague and black-tailed prairie dogs

    Science.gov (United States)

    Cully, Jack F.; Johnson, T.; Collinge, S.K.; Ray, C.

    2010-01-01

    Plague is an exotic vector-borne disease caused by the bacterium Yersinia pestis that causes mortality rates approaching 100% in black-tailed prairie dogs (Cynomys ludovicianus). We mapped the perimeter of the active portions of black-tailed prairie dog colonies annually between 1999 and 2005 at four prairie dog colony complexes in areas with a history of plague, as well as at two complexes that were located outside the distribution of plague at the time of mapping and had therefore never been affected by the disease. We hypothesized that the presence of plague would significantly reduce overall black-tailed prairie dog colony area, reduce the sizes of colonies on these landscapes, and increase nearest-neighbor distances between colonies. Within the region historically affected by plague, individual colonies were smaller, nearest-neighbor distances were greater, and the proportion of potential habitat occupied by active prairie dog colonies was smaller than at plague-free sites. Populations that endured plague were composed of fewer large colonies (>100 ha) than populations that were historically plague free. We suggest that these differences among sites in colony size and isolation may slow recolonization after extirpation. At the same time, greater intercolony distances may also reduce intercolony transmission of pathogens. Reduced transmission among smaller and more distant colonies may ultimately enhance long-term prairie dog population persistence in areas where plague is present.

  9. A comprehensive study on the role of the Yersinia pestis virulence markers in an animal model of pneumonic plague

    NARCIS (Netherlands)

    Kaman, W.E.; Hawkey, S.; van der Kleij, D.; Broekhuijsen, M.P.; Silman, N.J.; Bikker, F.J.

    2011-01-01

    Yersinia pestis, the Gram-negative bacterial agent of plague, is a zoonotic pathogen that primarily infects wild rodents and is transmitted by fleas. Y. pestis is one of the most invasive and virulent bacterial pathogens and has caused devastating pandemics, including the Black Death of 14th century

  10. Validation of inverse seasonal peak mortality in medieval plagues, including the Black Death, in comparison to modern Yersinia pestis-variant diseases.

    Directory of Open Access Journals (Sweden)

    Mark R Welford

    Full Text Available BACKGROUND: Recent studies have noted myriad qualitative and quantitative inconsistencies between the medieval Black Death (and subsequent "plagues" and modern empirical Y. pestis plague data, most of which is derived from the Indian and Chinese plague outbreaks of A.D. 1900+/-15 years. Previous works have noted apparent differences in seasonal mortality peaks during Black Death outbreaks versus peaks of bubonic and pneumonic plagues attributed to Y. pestis infection, but have not provided spatiotemporal statistical support. Our objective here was to validate individual observations of this seasonal discrepancy in peak mortality between historical epidemics and modern empirical data. METHODOLOGY/PRINCIPAL FINDINGS: We compiled and aggregated multiple daily, weekly and monthly datasets of both Y. pestis plague epidemics and suspected Black Death epidemics to compare seasonal differences in mortality peaks at a monthly resolution. Statistical and time series analyses of the epidemic data indicate that a seasonal inversion in peak mortality does exist between known Y. pestis plague and suspected Black Death epidemics. We provide possible explanations for this seasonal inversion. CONCLUSIONS/SIGNIFICANCE: These results add further evidence of inconsistency between historical plagues, including the Black Death, and our current understanding of Y. pestis-variant disease. We expect that the line of inquiry into the disputed cause of the greatest recorded epidemic will continue to intensify. Given the rapid pace of environmental change in the modern world, it is crucial that we understand past lethal outbreaks as fully as possible in order to prepare for future deadly pandemics.

  11. A bibliography of literature pertaining to plague (Yersinia pestis)

    Science.gov (United States)

    Ellison, Laura E.; Frank, Megan K. Eberhardt

    2011-01-01

    Plague is an acute and often fatal zoonotic disease caused by the bacterium Yersinia pestis. Y. pestis mainly cycles between small mammals and their fleas; however, it has the potential to infect humans and frequently causes fatalities if left untreated. It is often considered a disease of the past; however, since the late 1800s, plagueis geographic range has expanded greatly, posing new threats in previously unaffected regions of the world, including the Western United States. A literature search was conducted using Internet resources and databases. The keywords chosen for the searches included plague, Yersinia pestis, management, control, wildlife, prairie dogs, fleas, North America, and mammals. Keywords were used alone or in combination with the other terms. Although this search pertains mostly to North America, citations were included from the international research community, as well. Databases and search engines used included Google (http://www.google.com), Google Scholar (http://scholar.google.com), SciVerse Scopus (http://www.scopus.com), ISI Web of Knowledge (http://apps.isiknowledge.com), and the USGS Library's Digital Desktop (http://library.usgs.gov). The literature-cited sections of manuscripts obtained from keyword searches were cross-referenced to identify additional citations or gray literature that was missed by the Internet search engines. This Open-File Report, published as an Internet-accessible bibliography, is intended to be periodically updated with new citations or older references that may have been missed during this compilation. Hence, the authors would be grateful to receive notice of any new or old papers that the audience (users) think need to be included.

  12. Chicken dendritic cells are susceptible to highly pathogenic avian influenza viruses which induce strong cytokine responses

    NARCIS (Netherlands)

    Vervelde, L.; Reemens, S.S.; Haarlem, van D.A.; Post, J.; Claassen, E.A.W.; Rebel, J.M.J.; Jansen, C.A.

    2013-01-01

    Infection with highly pathogenic avian influenza (HPAI) in birds and mammals is associated with severe pathology and increased mortality. We hypothesize that in contrast to low pathogenicity avian influenza (LPAI) infection, HPAI infection of chicken dendritic cells (DC) induces a cytokine deregulat

  13. Was Plague an Exclusively Urban Phenomenon? Plague Mortality in the Seventeenth-Century Low Countries

    NARCIS (Netherlands)

    Curtis, D.R.

    2016-01-01

    Current scholarship reinforces the notion that by the early modern period, plague had become largely an urban concern in northwestern Europe. However, a data set comprised of burial information from the seventeenth-century Low Countries suggests that plague’s impact on the countryside was far more s

  14. Systemic Virus distribution and host responses in brain and intestine of chickens infected with low pathogenic and high pathogenic avian influenza virus

    NARCIS (Netherlands)

    Post, J.; Burt, D.W.; Cornelissen, J.B.W.J.; Broks, V.C.M.; Zoelen, van D.; Peeters, B.P.H.; Rebel, J.M.J.

    2012-01-01

    Background: Avian influenza virus (AIV) is classified into two pathotypes, low pathogenic (LP) and high pathogenic ( HP), based on virulence in chickens. Differences in pathogenicity between HPAIV and LPAIV might eventually be related to specific characteristics of strains, tissue tropism and host r

  15. Intronic deletions of tva receptor gene decrease the susceptibility to infection by subgroup A avian sarcoma and leukosis virus subgroup A

    Science.gov (United States)

    The group of avian sarcoma and leukosis virus (ASLV) in chickens contains six highly related subgroups, A to E and J. Four genetic loci, tva, tvb, tvc and tvj, encode for corresponding receptors that determine the susceptibility to the ASLV subgroups. The prevalence of ASLV in hosts may have imposed...

  16. A computationally optimized broadly reactive H5 hemagglutinin vaccine provides protection against homologous and heterologous H5N1 highly pathogenic avian influenza virus infection in chickens

    Science.gov (United States)

    Since its emergence in 1996 in China, H5N1 highly pathogenic avian influenza (HPAI) virus has continuously evolved into different genetic clades that have created challenges to maintaining antigenically relevant H5N1 vaccine seeds. Therefore, a universal (multi-hemagglutinin [HA] subtype) or more c...

  17. Estimating the per-contact probability of infection by highly pathogenic avian influenza (H7N7) virus during the 2003 epidemic in the Netherlands.

    NARCIS (Netherlands)

    Ssematimba, A.; Elbers, A.R.W.; Hagenaars, T.H.J.; Jong, de M.C.M.

    2012-01-01

    Estimates of the per-contact probability of transmission between farms of Highly Pathogenic Avian Influenza virus of H7N7 subtype during the 2003 epidemic in the Netherlands are important for the design of better control and biosecurity strategies. We used standardized data collected during the epid

  18. Influenza at the animal-human interface: a review of the literature for virological evidence of human infection with swine or avian influenza viruses other than A(H5N1).

    Science.gov (United States)

    Freidl, G S; Meijer, A; de Bruin, E; de Nardi, M; Munoz, O; Capua, I; Breed, A C; Harris, K; Hill, A; Kosmider, R; Banks, J; von Dobschuetz, S; Stark, K; Wieland, B; Stevens, K; van der Werf, S; Enouf, V; van der Meulen, K; Van Reeth, K; Dauphin, G; Koopmans, M

    2014-05-08

    Factors that trigger human infection with animal influenza virus progressing into a pandemic are poorly understood. Within a project developing an evidence-based risk assessment framework for influenza viruses in animals, we conducted a review of the literature for evidence of human infection with animal influenza viruses by diagnostic methods used. The review covering Medline, Embase, SciSearch and CabAbstracts yielded 6,955 articles, of which we retained 89; for influenza A(H5N1) and A(H7N9), the official case counts of t he World Health Organization were used. An additional 30 studies were included by scanning the reference lists. Here, we present the findings for confirmed infections with virological evidence. We found reports of 1,419 naturally infected human cases, of which 648 were associated with avian influenza virus (AIV) A(H5N1), 375 with other AIV subtypes, and 396 with swine influenza virus (SIV). Human cases naturally infected with AIV spanned haemagglutinin subtypes H5, H6, H7, H9 and H10. SIV cases were associated with endemic SIV of H1 and H3 subtype descending from North American and Eurasian SIV lineages and various reassortants thereof. Direct exposure to birds or swine was the most likely source of infection for the cases with available information on exposure.

  19. Investigation of Avian Influenza A Virus Infection among Occupational Exposed Population of Ningxia%宁夏职业暴露人群和环境高致病性禽流感感染情况调查

    Institute of Scientific and Technical Information of China (English)

    杨炬; 王雯; 高洁; 马少宁; 宁天江

    2013-01-01

    Objective To investigate the infection changes and environmental distribution of the H5N1 subtype avian influenza virus among occupational exposed population in Ningxia. Methods A sampling survey was conducted in Ningxia. The antibody and nucleate of H5N1 subtype avian influenza virus was detected in samples. Results 98. 30% of the occupational exposure population did not contact with dead poultry during the last month. The antibody and nucleate of H5N1 subtype avian influenza virus in all samples showed negative. However, H9 subtype positive rate was 6.98% among environmental samples. Conclusions The H5N1 subtype avian influenza virus infection was not found in occupational exposure population of Ningxia.%目的 了解高致病性禽流感病毒在宁夏职业暴露人群中的感染状况和其在环境中的分布情况,为相关研究和防控工作提供依据.方法 对银川市兴庆区、石嘴山市平罗县、吴忠市利通区、中卫市沙坡头区和固原市原州区五个调查点的职业人群进行抽样调查,问卷调查的同时采集调查对象的血清和对应的环境标本.血清标本利用马血球血凝抑制实验(HI)进行H5N1抗体检测.对环境标本进行禽流感病毒核酸检测.结果 98.30%的职业暴露人群近一个月没有接触过病死禽.调查对象的411份血清标本H5N1禽流感病毒抗体均为阴性,258份环境标本H5N1禽流感病毒核酸均为阴性,但发现环境标本H9亚型禽流感病毒阳性率为6 98%.结论 宁夏地区禽流感职业暴露人群中尚未发现H5N1高致病性禽流感病毒感染.应做好禽间和人间的禽流感病毒监测和防护教育.

  20. Dissociation of Tissue Destruction and Bacterial Expansion during Bubonic Plague.

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    Françoise Guinet

    2015-10-01

    Full Text Available Activation and/or recruitment of the host plasmin, a fibrinolytic enzyme also active on extracellular matrix components, is a common invasive strategy of bacterial pathogens. Yersinia pestis, the bubonic plague agent, expresses the multifunctional surface protease Pla, which activates plasmin and inactivates fibrinolysis inhibitors. Pla is encoded by the pPla plasmid. Following intradermal inoculation, Y. pestis has the capacity to multiply in and cause destruction of the lymph node (LN draining the entry site. The closely related, pPla-negative, Y. pseudotuberculosis species lacks this capacity. We hypothesized that tissue damage and bacterial multiplication occurring in the LN during bubonic plague were linked and both driven by pPla. Using a set of pPla-positive and pPla-negative Y. pestis and Y. pseudotuberculosis strains in a mouse model of intradermal injection, we found that pPla is not required for bacterial translocation to the LN. We also observed that a pPla-cured Y. pestis caused the same extensive histological lesions as the wild type strain. Furthermore, the Y. pseudotuberculosis histological pattern, characterized by infectious foci limited by inflammatory cell infiltrates with normal tissue density and follicular organization, was unchanged after introduction of pPla. However, the presence of pPla enabled Y. pseudotuberculosis to increase its bacterial load up to that of Y. pestis. Similarly, lack of pPla strongly reduced Y. pestis titers in LNs of infected mice. This pPla-mediated enhancing effect on bacterial load was directly dependent on the proteolytic activity of Pla. Immunohistochemistry of Pla-negative Y. pestis-infected LNs revealed extensive bacterial lysis, unlike the numerous, apparently intact, microorganisms seen in wild type Y. pestis-infected preparations. Therefore, our study demonstrates that tissue destruction and bacterial survival/multiplication are dissociated in the bubo and that the primary action of Pla

  1. Avian Flu (H7N9) in China

    Science.gov (United States)

    ... Mobile Apps RSS Feeds Avian Flu (H7N9) in China Recommend on Facebook Tweet Share Compartir Warning - Level ... of H7N9 have been reported outside of mainland China but most of these infections have occurred among ...

  2. Prevention and Treatment of Avian Influenza A Viruses in People

    Science.gov (United States)

    ... their saliva, mucous and feces. Human infections with bird flu viruses can happen when enough virus gets into ... Virus (CVV) for a Highly Pathogenic Avian Influenza (Bird Flu) Virus ” for more information on this process. ...

  3. Immuno-PCR--a new tool for paleomicrobiology: the plague paradigm.

    Directory of Open Access Journals (Sweden)

    Nada Malou

    Full Text Available BACKGROUND: The cause of past plague pandemics was controversial but several research teams used PCR techniques and dental pulp as the primary material to reveal that they were caused by Yersinia pestis. However, the degradation of DNA limits the ability to detect ancient infections. METHODS: We used for the first time immuno-PCR to detect Yersinia pestis antigens; it can detect protein concentrations 70 times lower than the standard ELISA. After determining the cut-off value, we tested 34 teeth that were obtained from mass graves of plague, and compared previous PCR results with ELISA and immuno-PCR results. RESULTS: The immuno-PCR technique was the most sensitive (14 out of 34 followed by the PCR technique (10 out of 34 and ELISA (3 out of 34. The combination of these three methods identified 18 out of 34 (53% teeth as presumably being from people with the plague. CONCLUSION: Immuno-PCR is specific (no false-positive samples were found and more sensitive than the currently used method to detect antigens of ancient infections in dental pulp. The combination of three methods, ELISA, PCR and immuno-PCR, increased the capacity to identify ancient pathogens in dental pulp.

  4. Immuno-PCR - A New Tool for Paleomicrobiology: The Plague Paradigm

    Science.gov (United States)

    Nappez, Claude; Signoli, Michel; Le Forestier, Cyrille; Castex, Dominique; Drancourt, Michel; Raoult, Didier

    2012-01-01

    Background The cause of past plague pandemics was controversial but several research teams used PCR techniques and dental pulp as the primary material to reveal that they were caused by Yersinia pestis. However, the degradation of DNA limits the ability to detect ancient infections. Methods We used for the first time immuno-PCR to detect Yersinia pestis antigens; it can detect protein concentrations 70 times lower than the standard ELISA. After determining the cut-off value, we tested 34 teeth that were obtained from mass graves of plague, and compared previous PCR results with ELISA and immuno-PCR results. Results The immuno-PCR technique was the most sensitive (14 out of 34) followed by the PCR technique (10 out of 34) and ELISA (3 out of 34). The combination of these three methods identified 18 out of 34 (53%) teeth as presumably being from people with the plague. Conclusion Immuno-PCR is specific (no false-positive samples were found) and more sensitive than the currently used method to detect antigens of ancient infections in dental pulp. The combination of three methods, ELISA, PCR and immuno-PCR, increased the capacity to identify ancient pathogens in dental pulp. PMID:22347507

  5. Detecting emerging transmissibility of avian influenza virus in human households.

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    Michiel van Boven

    2007-07-01

    Full Text Available Accumulating infections of highly pathogenic H5N1 avian influenza in humans underlines the need to track the ability of these viruses to spread among humans. A human-transmissible avian influenza virus is expected to cause clusters of infections in humans living in close contact. Therefore, epidemiological analysis of infection clusters in human households is of key importance. Infection clusters may arise from transmission events from (i the animal reservoir, (ii humans who were infected by animals (primary human-to-human transmission, or (iii humans who were infected by humans (secondary human-to-human transmission. Here we propose a method of analysing household infection data to detect changes in the transmissibility of avian influenza viruses in humans at an early stage. The method is applied to an outbreak of H7N7 avian influenza virus in The Netherlands that was the cause of more than 30 human-to-human transmission events. The analyses indicate that secondary human-to-human transmission is plausible for the Dutch household infection data. Based on the estimates of the within-household transmission parameters, we evaluate the effectiveness of antiviral prophylaxis, and conclude that it is unlikely that all household infections can be prevented with current antiviral drugs. We discuss the applicability of our method for the detection of emerging human-to-human transmission of avian influenza viruses in particular, and for the analysis of within-household infection data in general.

  6. The effect and influence of closing live poultry markets to control and prevent human avian in fluenza infection%关闭活禽市场对防控人感染禽流感的成效与影响

    Institute of Scientific and Technical Information of China (English)

    谭兆营; 沈雅; 杨丹丹

    2013-01-01

    活禽市场是城市人群感染禽流感的关键场所.关闭活禽市场,可以减少公众暴露风险,但无法从根本上杜绝人群暴露机会,禽流感真正的风险源是野鸟的高带毒率和分散、混乱的养殖,源头环节才是控制禽流感的关键.因此,关闭活禽市场并不能彻底改变鸟禽间的病毒感染谱和流行态势,对禽流感传播流行链影响有限,关闭活禽市场不仅剥夺了消费者的选择权,长远看也不利于家禽养殖业的健康发展和市场多元化需求,进而影响社会和经济的发展.%Live poultry markets are a critical risk factor for urban populations infected with avian influenza.Closing the live poultry markets could reduce the risk of public exposure,but would not fundamentally eliminate the potential for exposure.The true source of risk is the high infection rate of wild birds as well as dispersed and disorganized poultry farming practices.Source is the key control point for avian influenza.Therefore,shutting down live poultry markets is not a complete solution to changing the spectrum of infection and limiting the spread of avian influenza.Shutting down live poultry markets will have a limited impact on the chain of infection,and will only serve to deprive consumers of their right to choose.Looking to the future,this approach is also likely to have negative consequences for the healthy development of the poultry industry,and with it further impacts to societal and economic development.

  7. Early host cell targets of Yersinia pestis during primary pneumonic plague.

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    Roger D Pechous

    Full Text Available Inhalation of Yersinia pestis causes primary pneumonic plague, a highly lethal syndrome with mortality rates approaching 100%. Pneumonic plague progression is biphasic, with an initial pre-inflammatory phase facilitating bacterial growth in the absence of host inflammation, followed by a pro-inflammatory phase marked by extensive neutrophil influx, an inflammatory cytokine storm, and severe tissue destruction. Using a FRET-based probe to quantitate injection of effector proteins by the Y. pestis type III secretion system, we show that these bacteria target alveolar macrophages early during infection of mice, followed by a switch in host cell preference to neutrophils. We also demonstrate that neutrophil influx is unable to limit bacterial growth in the lung and is ultimately responsible for the severe inflammation during the lethal pro-inflammatory phase.

  8. Duck plague: carrier state and gross pathology in black ducks

    Science.gov (United States)

    Ossa, Jorge E.

    1975-01-01

    Duck plague (UP) is a highly fatal disease of ducks, geese, and swans (family Anatidae), produced by a reticulo-endotheliotrophic virus classified as a member of the Herpesvirus group. The disease was recognized in Europe in 1949. On the American continent, the disease was first diagnosed in the United States in 1967. Very little is known of DP virus ecology, particularly of the mechanisms of interepizootic survival and movement. The tendency of the IIerpesviruses to enter into a quiescent state after an overt or inapparent infection is a proven characteristic for most of the members of this group. Herpes simplex, which is the model of the Herpesviruses, is said to be the classical example of a persistent recurrent viral infection. Burnet and Williams (4) were the first to recognize this kind of relationship between herpes simplex and its host in 1939. Later, it was found that the reactivation of the virus can be brought on by a variety of stimuli either physiological (menstruation), pathological (anaphylactic shock), chemical (pesticides) or physical (sunburn). This same latency property has been proved for every member of this group of viruses which has been studied adequately, DP is among the few Herpesviruses for which the carrier state has not been demonstrated, but there is circumstantial evidence suggesting it. The carrier state for DP seems to be a likely explanation for the persistence and the particular pattern of movement of this disease.

  9. Avian influenza A(H7N9) and (H5N1) infections among poultry and swine workers and the general population in Beijing, China, 2013–2015

    Science.gov (United States)

    Yang, Peng; Ma, Chunna; Cui, Shujuan; Zhang, Daitao; Shi, Weixian; Pan, Yang; Sun, Ying; Lu, Guilan; Peng, Xiaomin; Zhao, Jiachen; Liu, Yimeng; Wang, Quanyi

    2016-01-01

    Although several studies have reported seroprevalences of antibody against avian influenza A(H7N9) virus among poultry workers in southern China, results have varied and data in northern China are scarce. To understand risks of H7N9 and H5N1 virus infections in northern China, a serological cohort study was conducted. Poultry workers, swine workers and the general population in Beijing, China, were evaluated through three surveys in November 2013, April 2014 and April 2015. The highest seroprevalence to H7N9 virus among poultry workers was recorded in the April 2014 and April 2015 surveys (0.4%), while that to H5N1 clade 2.3.4 or clade 2.3.2.1 virus was noted in the April 2014 survey (1.6% and 0.2%, respectively). The incidence of H7N9 virus infections among poultry workers (1.6/1000 person-months) was significantly lower than that of H5N1 clade 2.3.4 infections (3.8/1000 person-months) but higher than that of H5N1 clade 2.3.2.1 infections (0.3/1000 person-months). Compared with the general population, poultry workers were at higher risk of contracting H7N9 virus (IRR: 34.90; p H7N9 and H5N1 virus infections remain low in Beijing, continued preventive measures are warranted for poultry workers. PMID:27670286

  10. Where does human plague still persist in Latin America?

    Directory of Open Access Journals (Sweden)

    Maria Cristina Schneider

    2014-02-01

    Full Text Available BACKGROUND: Plague is an epidemic-prone disease with a potential impact on public health, international trade, and tourism. It may emerge and re-emerge after decades of epidemiological silence. Today, in Latin America, human cases and foci are present in Bolivia, Brazil, Ecuador, and Peru. AIMS: The objective of this study is to identify where cases of human plague still persist in Latin America and map areas that may be at risk for emergence or re-emergence. This analysis will provide evidence-based information for countries to prioritize areas for intervention. METHODS: Evidence of the presence of plague was demonstrated using existing official information from WHO, PAHO, and Ministries of Health. A geo-referenced database was created to map the historical presence of plague by country between the first registered case in 1899 and 2012. Areas where plague still persists were mapped at the second level of the political/administrative divisions (counties. Selected demographic, socioeconomic, and environmental variables were described. RESULTS: Plague was found to be present for one or more years in 14 out of 25 countries in Latin America (1899-2012. Foci persisted in six countries, two of which have no report of current cases. There is evidence that human cases of plague still persist in 18 counties. Demographic and poverty patterns were observed in 11/18 counties. Four types of biomes are most commonly found. 12/18 have an average altitude higher than 1,300 meters above sea level. DISCUSSION: Even though human plague cases are very localized, the risk is present, and unexpected outbreaks could occur. Countries need to make the final push to eliminate plague as a public health problem for the Americas. A further disaggregated risk evaluation is recommended, including identification of foci and possible interactions among areas where plague could emerge or re-emerge. A closer geographical approach and environmental characterization are suggested.

  11. Avian influenza virus and Newcastle disease virus

    Science.gov (United States)

    Avian influenza virus (AIV) and Newcastle disease virus (NDV) severely impact poultry egg production. Decreased egg yield and hatchability, as well as misshapen eggs, are often observed during infection with AIV and NDV, even with low-virulence strains or in vaccinated flocks. Data suggest that in...

  12. Evaluation of two commercial lateral flow devices (LFDs) used for flockside testing of H5N1 highly-pathogenic avian influenza infections in backyard gallinaceous poultry in Egypt.

    Science.gov (United States)

    Soliman, Mohammed; Selim, Abdullah; Coward, Vivien J; Hassan, Mohammed K; Aly, Mona M; Banks, Jill; Slomka, Marek J

    2010-10-13

    Quickvue and Anigen lateral flow devices (LFDs) were evaluated for detection of H5N1 highly pathogenic avian influenza (HPAI) infections in Egyptian poultry. Sixty five chickens and two turkeys were sampled in eight flocks where H5N1 HPAI infection was suspected. Swabs (tracheal and cloacal) and feathers were collected from each bird for flockside testing by the two LFDs. The same clinical specimens were transported for laboratory testing by M gene RRT PCR where a positive result by this "gold standard" test for one or both swabs from a given bird indicated infection at the bird level, showing 57 birds (including 15 carcassess) to be truly AI infected. Among these 57, similar bird-level LFD testing of swabs showed 43 and 44 to be AI infected by Quickvue and Anigen LFDs, respectively. Nine birds were AI negative by M gene RRT PCR and both LFDs, and one was M gene RRT PCR negative but positive by both LFDs, suggesting one false positive LFD result. Sensitivities of the LFDs relative to M gene RRT PCR were 77.2% for Anigen and 75.4% for Quickvue tests, with 90.0% specificity for both. By including feathers with swabs for LFD testing, the number of LFD positives among 57 infected birds increased by four to 48 by Anigen and 47 by Quickvue, increasing the sensitivity of the LFDs to 84.2% and 82.5% for Anigen and Quickvue, respectively. Although LFD sensitivity cannot compare to the high sensitivity displayed by validated AI RRT PCRs, they may be utilised for flockside testing of birds infected with HPAI at the peak of viral shedding, when birds are displaying advanced clinical signs or sampled as fresh carcasses. Swabs are classic field specimens collected from outbreaks, but inclusion of feathers from birds infected with H5N1 HPAI increased LFD sensitivity. However, the LFD false positive observation emphasises the importance of returning samples for confirmatory laboratory testing.

  13. Avian zoonoses – a review

    Directory of Open Access Journals (Sweden)

    Kozdruń Wojciech

    2015-06-01

    Full Text Available Birds are one of the most interesting and most colourful groups of animals, but they can also be a source of zoonotic factors dangerous for humans. This paper describes the threats to human health from contact with birds. The most vulnerable occupational groups associated with birds are veterinarians, owners of poultry farms, breeders of ornamental birds, zoo personnel, and poultry slaughterhouse workers. Ornithosis is the most dangerous zoonosis of the avian bacterial diseases. Among other hazardous bacterial factors, Salmonella and Campylobacter are responsible for gastrointestinal diseases. Avian influenza is the most dangerous of the viral diseases. It should be noted, however, that avian influenza is a disease of birds, not humans. The recent threat which has appeared is infection with West Nile virus. The results of serological examinations of birds and humans indicate that the virus exists in our ecosystem. Allergic alveolitis connected with the pigeon tick and the Dermanyssus gallinae mite also merits mention. In any case, where people have contact with birds or their droppings and secretions, special precautions should be taken. This way the negative effects of birds on human health can be minimised or eliminated

  14. Plague and landscape resilience in premodern Iceland.

    Science.gov (United States)

    Streeter, Richard; Dugmore, Andrew J; Vésteinsson, Orri

    2012-03-01

    In debates on societal collapse, Iceland occupies a position of precarious survival, defined by not becoming extinct, like Norse Greenland, but having endured, sometimes by the narrowest of margins. Classic decline narratives for late medieval to early modern Iceland stress compounding adversities, where climate, trade, political domination, unsustainable practices, and environmental degradation conspire with epidemics and volcanism to depress the Icelanders and turn the once-proud Vikings and Saga writers into one of Europe's poorest nations. A mainstay of this narrative is the impact of incidental setbacks such as plague and volcanism, which are seen to have compounded and exacerbated underlying structural problems. This research shows that this view is not correct. We present a study of landscape change that uses 15 precisely dated tephra layers spanning the whole 1,200-y period of human settlement in Iceland. These tephras have provided 2,625 horizons of known age within 200 stratigraphic sections to form a high-resolution spatial and temporal record of change. This finding shows short-term (50 y) declines in geomorphological activity after two major plagues in A.D. 15th century, variations that probably mirrored variations in the population. In the longer term, the geomorphological impact of climate changes from the 14th century on is delayed, and landscapes (as well as Icelandic society) exhibit resilience over decade to century timescales. This finding is not a simple consequence of depopulation but a reflection of how Icelandic society responded with a scaling back of their economy, conservation of core functionality, and entrenchment of the established order.

  15. Use of a public telephone hotline to detect urban plague cases.

    Science.gov (United States)

    Malberg, J A; Pape, W J; Lezotte, D; Hill, A E

    2012-11-01

    Current methods for vector-borne disease surveillance are limited by time and cost. To avoid human infections from emerging zoonotic diseases, it is important that the United States develop cost-effective surveillance systems for these diseases. This study examines the methodology used in the surveillance of a plague epizootic involving tree squirrels (Sciurus niger) in Denver Colorado, during the summer of 2007. A call-in centre for the public to report dead squirrels was used to direct animal carcass sampling. Staff used these reports to collect squirrel carcasses for the analysis of Yersinia pestis infection. This sampling protocol was analysed at the census tract level using Poisson regression to determine the relationship between higher call volumes in a census tract and the risk of a carcass in that tract testing positive for plague. Over-sampling owing to call volume-directed collection was accounted for by including the number of animals collected as the denominator in the model. The risk of finding an additional plague-positive animal increased as the call volume per census tract increased. The risk in the census tracts with >3 calls a month was significantly higher than that with three or less calls in a month. For tracts with 4-5 calls, the relative risk (RR) of an additional plague-positive carcass was 10.08 (95% CI 5.46-18.61); for tracts with 6-8 calls, the RR = 5.20 (2.93-9.20); for tracts with 9-11 calls, the RR = 12.80 (5.85-28.03) and tracts with >11 calls had RR = 35.41 (18.60-67.40). Overall, the call-in centre directed sampling increased the probability of locating plague-infected carcasses in the known Denver epizootic. Further studies are needed to determine the effectiveness of this methodology at monitoring large-scale zoonotic disease occurrence in the absence of a recognized epizootic.

  16. Possible vector dissemination by swift foxes following a plague epizootic in black-tailed prairie dogs in northwestern Texas.

    Science.gov (United States)

    McGee, Brady K; Butler, Matthew J; Pence, Danny B; Alexander, James L; Nissen, Janet B; Ballard, Warren B; Nicholson, Kerry L

    2006-04-01

    To determine whether swift foxes (Vulpes velox) could facilitate transmission of Yersinia pestis to uninfected black-tailed prairie dog (Cynomys ludovicianus) colonies by acquiring infected fleas, ectoparasite and serologic samples were collected from swift foxes living adjacent to prairie dog towns during a 2004 plague epizootic in northwestern Texas, USA. A previous study (1999-2001) indicated that these swift foxes were infested almost exclusively with the flea Pulex irritans. Black-tailed prairie dogs examined from the study area harbored only Pulex simulans and Oropsylla hirsuta. Although P. irritans was most common, P. simulans and O. hirsuta were collected from six swift foxes and a single coyote (Canis latrans) following the plague epizootic. Thus, both of these canids could act as transport hosts (at least temporarily) of prairie dog fleas following the loss of their normal hosts during a plague die-off. All six adult swift foxes tested positive for antibodies to Y. pestis. All 107 fleas from swift foxes tested negative for Y. pestis by mouse inoculation. Although swift foxes could potentially carry Y. pestis to un-infected prairie dog colonies, we believe they play only a minor role in plague epidemiology, considering that they harbored just a few uninfected prairie dog fleas (P. simulans and O. hirsuta).

  17. Diffferential innate responses of chickens and ducks to low pathogenic avian influenza virus

    NARCIS (Netherlands)

    Cornelissen, J.B.W.J.; Post, J.; Peeters, B.P.H.; Vervelde, L.; Rebel, J.M.J.

    2012-01-01

    Ducks and chickens are hosts of avian influenza virus, each with distinctive responses to infection. To understand these differences, we characterized the innate immune response to low pathogenicity avian influenza virus H7N1 infection in chickens and ducks. Viral RNA was detected in the lungs of ch

  18. 人感染H7N9禽流感诊治概况%Current situation of the diagnosis and treatment of human infection with avian influenza A (H7N9) virus

    Institute of Scientific and Technical Information of China (English)

    朱翠云; 张永信

    2013-01-01

      The cases of human infection caused by avian influenza A (H7N9) virus are first reported in Shanghai in March 2013. It was caused by a novel reassortant avian-origin H7N9 virus which was first discovered by the key laboratory of Shanghai public health clinical center and finally confirmed by Chinese Center for Disease Control and Prevention. All three patients were died of severe and fatal respiratory disease. The situation raises many urgent questions and global public health concerns due to limited knowledge about it. We briefly reviewed the epidemiology, clinical feature, diagnosis and treatment of the disease. The source of infection is from birds and the mode of transmission is by respiratory transmission. The clinical features of human infection caused by avian influenza A (H7N9) virus include fulminant pneumonia, respiratory failure, acute respiratory distress syndrome (ARDS), multiorgan failure. The confirmed evidence is that isolation of H7N9 virus RNA from respiratory specimens by RT-PCR. The anti-influenza drugs known as neuraminidase inhibitors (oral oseltamivir and inhaled zanamivir) are the first choice and should be administered to patients with suspected or confirmed avian influenza A (H7N9) virus infection as soon as possible, best within 48 hours of onset.%  2013年3月中国上海首先报道了人感染H7N9禽流感病例,这是由上海市公共卫生临床中心应急实验室首先发现,经中国疾病预防控制中心确认的新型重配禽流感病毒H7N9亚型所引起的人感染病例,在患者呼吸道标本中检测到该病毒,该病毒可引起快速进展的重症肺炎及多脏器功能衰竭,3例病例均已死亡。由于这是一种新的病毒引起的禽源性呼吸道传染病,人类所知有限,引起全世界的关注。本文根据已获得的资料,从流行病学、临床表现、诊断与治疗等方面对该新发现的疾病做一介绍。该病在流行病学上有禽类接触史,经

  19. Disease Limits Populations: Plague and Black-Tailed Prairie Dogs

    OpenAIRE

    Cully, Jack F.; Johnson, Tammi L.; Collinge, Sharon K.; Ray, Chris

    2010-01-01

    Plague is an exotic vector-borne disease caused by the bacterium Yersinia pestis that causes mortality rates approaching 100% in black-tailed prairie dogs (Cynomys ludovicianus). We mapped the perimeter of the active portions of black-tailed prairie dog colonies annually between 1999 and 2005 at four prairie dog colony complexes in areas with a history of plague, as well as at two complexes that were located outside the distribution of plague at the time of mapping and had therefore never bee...

  20. Immunodominant epitopes mapped by synthetic peptides on the capsid protein of avian hepatitis E virus are non-protective.

    Science.gov (United States)

    Guo, Hailong; Zhou, E M; Sun, Z F; Meng, X J

    2008-03-01

    Avian hepatitis E virus (avian HEV) was recently discovered in chickens with hepatitis-splenomegaly syndrome in the United States. The open reading frame 2 (ORF2) protein of avian HEV has been shown to cross-react with human and swine HEV ORF2 proteins, and immunodominant antigenic epitopes on avian HEV ORF2 protein were identified in the predicted antigenic domains by synthetic peptides. However, whether these epitopes are protective against avian HEV infection has not been investigated. In this study, groups of chickens were immunized with keyhole limpet hemocyanin (KLH)-conjugated peptides and recombinant avian HEV ORF2 antigen followed by challenge with avian HEV virus to assess the protective capacity of these peptides containing the epitopes. While avian HEV ORF2 protein showed complete protection against infection, viremia and fecal virus shedding were found in all peptide-immunized chickens. Using purified IgY from normal, anti-peptide, and anti-avian HEV ORF2 chicken sera, an in-vitro neutralization and in-vivo monitoring assay was performed to further evaluate the neutralizing ability of anti-peptide IgY. Results showed that none of the anti-peptide IgY can neutralize avian HEV in vitro, as viremia, fecal virus shedding, and seroconversion appeared similarly in chickens inoculated with avian HEV mixed with anti-peptide IgY and chickens inoculated with avian HEV mixed with normal IgY. As expected, chickens inoculated with the avian HEV and anti-avian HEV ORF2 IgY mixture did not show detectable avian HEV infection. Taken together, the results of this study demonstrated that immunodominant epitopes on avian HEV ORF2 protein identified by synthetic peptides are non-protective, suggesting protective neutralizing epitope on avian HEV ORF2 may not be linear as is human HEV.

  1. Avian Chlamydiosis Zoonotic Disease.

    Science.gov (United States)

    Szymańska-Czerwińska, Monika; Niemczuk, Krzysztof

    2016-01-01

    This review presents recent data about avian chlamydiosis. Chlamydia psittaci has been considered to be the main causative agent of chlamydiosis in birds; however, two new Chlamydia species have been detected recently-C. gallinacea in breeding birds and C. avium in wild birds. We discuss the zoonotic potential of avian Chlamydia species.

  2. Correlation between reported human infection with avian influenza A H7N9 virus and cyber user awareness: what can we learn from digital epidemiology?

    Science.gov (United States)

    Xie, Tiansheng; Yang, Zongxing; Yang, Shigui; Wu, Nanping; Li, Lanjuan

    2014-05-01

    Data on the topic of novel avian influenza A (H7N9) were collected based on the web analysis tool 'Baidu Index', a major Chinese search engine. We found a positive correlation between the volume of H7N9-related 'cyber user awareness' and the epidemic situation during the H7N9 outbreak in China (r=0.98, pH7N9-related topics changed at different epidemic stages. This study may improve our understanding of the role of web-based media in infectious disease surveillance in China.

  3. 四川省鼠疫防治30年回顾%Review of Plague Control and Prevention in Sichuan Province, 1981 -2010

    Institute of Scientific and Technical Information of China (English)

    汪立茂; 吴朝学; 吴建林; 祝小平; 陈开华; 谢飞; 李光清; 罗志丹巴; 段勇军; 李帆; 祁腾

    2012-01-01

    Objective To provide strategy for plague prevention and control based on the analysis of plague prevention and control in Sichuan province during 1981 -2010. Methods The data of the plague surveillance in Sichuan province during 1981 - 2010 were collected,, arranged and analyzed. Experimental method was accordance with the " diagnostic criteria for plague". Results Totally 42 429 bacteriological materials were tested, 183 strains of yersinia pestis were isolated In indirect tests of blood, 29 980 suspected plague serum smples were tested, in which 251 were positive. Radioimmunoassay precipitation test showed that 79 in 7 611 samples were positive. Reverse suspected plague detection showed that 31 in 833 were positive. Seven species of infected animals and 3 infected medium were found. The Microtus fuscus and the Marmota himalayana plague bacteria were found. And plague occurred in 5 towns and 2 counties. Conclusion The existence of natural foci of plague in Sichuan was confirmed, and Microtus fuscus plague foci and natural foci of the himalayana marmota were found.%目的 分析四川省1981-2010年鼠疫防治的研究结果,为四川鼠疫防控工作提供对策与依据.方法 统计、整理、分析四川省1981-2010年鼠疫相关工作资料,实验方法按照“鼠疫诊断标准”进行.结果 通过调查,细菌学检测材料42 429份、分离鼠疫菌183株,鼠疫间接血疑试验血清29 980份、阳性251份,鼠疫放射免疫沉淀试验标本7 611份、阳性79份,鼠疫反向血疑试验检测标本833份、阳性31份,发现染疫动物7种,染疫媒介3种,发现青海田鼠型鼠疫菌和喜马拉雅旱獭型鼠疫菌,鼠疫发生在2县5个乡镇.结论 证实了四川鼠疫自然疫源地的存在,发现了青海田鼠疫源地和喜马拉雅旱獭鼠疫自然疫源地.

  4. Circumventing Y. pestis Virulence by Early Recruitment of Neutrophils to the Lungs during Pneumonic Plague.

    Directory of Open Access Journals (Sweden)

    Yaron Vagima

    2015-05-01

    Full Text Available Pneumonic plague is a fatal disease caused by Yersinia pestis that is associated with a delayed immune response in the lungs. Because neutrophils are the first immune cells recruited to sites of infection, we investigated the mechanisms responsible for their delayed homing to the lung. During the first 24 hr after pulmonary infection with a fully virulent Y. pestis strain, no significant changes were observed in the lungs in the levels of neutrophils infiltrate, expression of adhesion molecules, or the expression of the major neutrophil chemoattractants keratinocyte cell-derived chemokine (KC, macrophage inflammatory protein 2 (MIP-2 and granulocyte colony stimulating factor (G-CSF. In contrast, early induction of chemokines, rapid neutrophil infiltration and a reduced bacterial burden were observed in the lungs of mice infected with an avirulent Y. pestis strain. In vitro infection of lung-derived cell-lines with a YopJ mutant revealed the involvement of YopJ in the inhibition of chemoattractants expression. However, the recruitment of neutrophils to the lungs of mice infected with the mutant was still delayed and associated with rapid bacterial propagation and mortality. Interestingly, whereas KC, MIP-2 and G-CSF mRNA levels in the lungs were up-regulated early after infection with the mutant, their protein levels remained constant, suggesting that Y. pestis may employ additional mechanisms to suppress early chemoattractants induction in the lung. It therefore seems that prevention of the early influx of neutrophils to the lungs is of major importance for Y. pestis virulence. Indeed, pulmonary instillation of KC and MIP-2 to G-CSF-treated mice infected with Y. pestis led to rapid homing of neutrophils to the lung followed by a reduction in bacterial counts at 24 hr post-infection and improved survival rates. These observations shed new light on the virulence mechanisms of Y. pestis during pneumonic plague, and have implications for the

  5. Resistance to plague among black-tailed prairie dog populations

    Science.gov (United States)

    Rocke, Tonie E.; Williamson, Judy; Cobble, Kacy R.; Busch, Joseph D.; Antolin, Michael F.; Wagner, David M.

    2012-01-01

    In some rodent species frequently exposed to plague outbreaks caused by Yersinia pestis, resistance to the disease has evolved as a population trait. As a first step in determining if plague resistance has developed in black-tailed prairie dogs (Cynomys ludovicianus), animals captured from colonies in a plague-free region (South Dakota) and two plague-endemic regions (Colorado and Texas) were challenged with Y. pestis at one of three doses (2.5, 250, or 2500 mouse LD50s). South Dakota prairie dogs were far more susceptible to plague than Colorado and Texas prairie dogs (pdogs were quite similar in their response, with overall survival rates of 50% and 60%, respectively. Prairie dogs from these states were heterogenous in their response, with some animals dying at the lowest dose (37% and 20%, respectively) and some surviving even at the highest dose (29% and 40%, respectively). Microsatellite analysis revealed that all three groups were distinct genetically, but further studies are needed to establish a genetic basis for the observed differences in plague resistance.

  6. [Control and eradication strategies for classic fowl plague in Germany and the European Union].

    Science.gov (United States)

    Werner, Ortrud; Harder, Timm C

    2006-01-01

    The huge potential economic impact of highly pathogenic avian influenza (HPAI) substantiates specific and rigorous legal regulations worldwide. According to the O.I.E. Terrestrial Animal Health Code fowl plague is a notifiable disease. International trading activities concerning poultry and poultry products originating from countries with active HPAI are rigorously restricted. In EU member states directive 92/40/EEC subsumes measures against fowl plague and has been transferred into German legislation by the "Geflügelpest-Verordnung". These acts specify that vaccination against HPAI is principally prohibited. The aim of all sanctions is the extinction of disease and the eradication of the causative agent. However, HPAI viruses, exclusively belonging to subtypes H5 and H7, can re-emerge de novo from progenitor viruses of low pathogenicity which are perpetuated in the wild bird population. An outbreak of HPAI requires prompt action by a stamping out strategy. Fast and accurate diagnosis, a strict stand-still and the culling of affected flocks are at the basis of success. In areas with a high density of poultry holdings preemptive culling and creation of buffer zones, devoid of susceptible poultry, may be neccessary. In these cases emergency vaccinations can be considered as a supportive measure in order to limit mass culling. Vaccinations on merely prophylactic grounds, not being connected to acute outbreaks, should be avoided beware of selective pressures on the virus leading to antigenic drift and escape of vaccine-induced immunity. Instead, high standard biosecurity measures, particularly limiting direct and indirect contacts with wild birds, should be maintained.

  7. Intense circulation of A/H5N1 and other avian influenza viruses in Cambodian live-bird markets with serological evidence of sub-clinical human infections.

    Science.gov (United States)

    Horm, Srey Viseth; Tarantola, Arnaud; Rith, Sareth; Ly, Sowath; Gambaretti, Juliette; Duong, Veasna; Y, Phalla; Sorn, San; Holl, Davun; Allal, Lotfi; Kalpravidh, Wantanee; Dussart, Philippe; Horwood, Paul F; Buchy, Philippe

    2016-07-20

    Surveillance for avian influenza viruses (AIVs) in poultry and environmental samples was conducted in four live-bird markets in Cambodia from January through November 2013. Through real-time RT-PCR testing, AIVs were detected in 45% of 1048 samples collected throughout the year. Detection rates ranged from 32% and 18% in duck and chicken swabs, respectively, to 75% in carcass wash water samples. Influenza A/H5N1 virus was detected in 79% of samples positive for influenza A virus and 35% of all samples collected. Sequence analysis of full-length haemagglutinin (HA) and neuraminidase (NA) genes from A/H5N1 viruses, and full-genome analysis of six representative isolates, revealed that the clade 1.1.2 reassortant virus associated with Cambodian human cases during 2013 was the only A/H5N1 virus detected during the year. However, multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) analysis of HA and NA genes revealed co-circulation of at least nine low pathogenic AIVs from HA1, HA2, HA3, HA4, HA6, HA7, HA9, HA10 and HA11 subtypes. Four repeated serological surveys were conducted throughout the year in a cohort of 125 poultry workers. Serological testing found an overall prevalence of 4.5% and 1.8% for antibodies to A/H5N1 and A/H9N2, respectively. Seroconversion rates of 3.7 and 0.9 cases per 1000 person-months participation were detected for A/H5N1 and A/H9N2, respectively. Peak AIV circulation was associated with the Lunar New Year festival. Knowledge of periods of increased circulation of avian influenza in markets should inform intervention measures such as market cleaning and closures to reduce risk of human infections and emergence of novel AIVs.

  8. Diagnosis of Avian Leukosis Virus Subgroup J Infection in Luhua Chickens%芦花鸡J亚群白血病的综合诊断

    Institute of Scientific and Technical Information of China (English)

    李宏民; 刘蒙达; 孙洪磊; 肖一红; 刘思当

    2010-01-01

    @@ 1989年,Pavne[1]圾其同事首次从肉种鸡群中分离出禽J亚群白血病病毒(avian leukosis virus subtype J,ALV-J).最初ALV-J主要引起成年肉鸡以骨髓细胞瘤为主的白血病,感染鸡群发生肿瘤,生产性能降低,死亡率增高,药费增加,鸡群有很高的发病率和死亡率,死亡高峰时每月死亡率可达6%,严重影响肉鸡业的健康发展[2-3].

  9. Avian hepatitis E virus, vaccines and methods of protecting against avian hepatitis-splenomegaly syndrome and mammalian hepatitis E

    OpenAIRE

    2009-01-01

    The present invention relates to a novel isolated avian hepatitis E virus having a nucleotide sequence set forth in SEQ ID NO:1 or its complementary strand. The invention further concerns immunogenic compositions comprising this new virus or recombinant products such as the nucleic acid and vaccines that protect an avian or mammalian species from viral infection or hepatitis-splenomegaly syndrome caused by the hepatitis E virus. Also included in the scope of the invention is a method for prop...

  10. Identification of climate factors related to human infection with avian influenza A H7N9 and H5N1 viruses in China

    Science.gov (United States)

    Li, Jing; Rao, Yuhan; Sun, Qinglan; Wu, Xiaoxu; Jin, Jiao; Bi, Yuhai; Chen, Jin; Lei, Fumin; Liu, Qiyong; Duan, Ziyuan; Ma, Juncai; Gao, George F.; Liu, Di; Liu, Wenjun

    2015-01-01

    Human influenza infections display a strongly seasonal pattern. However, whether H7N9 and H5N1 infections correlate with climate factors has not been examined. Here, we analyzed 350 cases of H7N9 infection and 47 cases of H5N1 infection. The spatial characteristics of these cases revealed that H5N1 infections mainly occurred in the South, Middle, and Northwest of China, while the occurrence of H7N9 was concentrated in coastal areas of East and South of China. Aside from spatial-temporal characteristics, the most adaptive meteorological conditions for the occurrence of human infections by these two viral subtypes were different. We found that H7N9 infections correlate with climate factors, especially temperature (TEM) and relative humidity (RHU), while H5N1 infections correlate with TEM and atmospheric pressure (PRS). Hence, we propose a risky window (TEM 4–14 °C and RHU 65–95%) for H7N9 infection and (TEM 2–22 °C and PRS 980-1025 kPa) for H5N1 infection. Our results represent the first step in determining the effects of climate factors on two different virus infections in China and provide warning guidelines for the future when provinces fall into the risky windows. These findings revealed integrated predictive meteorological factors rooted in statistic data that enable the establishment of preventive actions and precautionary measures against future outbreaks. PMID:26656876

  11. Identification of climate factors related to human infection with avian influenza A H7N9 and H5N1 viruses in China.

    Science.gov (United States)

    Li, Jing; Rao, Yuhan; Sun, Qinglan; Wu, Xiaoxu; Jin, Jiao; Bi, Yuhai; Chen, Jin; Lei, Fumin; Liu, Qiyong; Duan, Ziyuan; Ma, Juncai; Gao, George F; Liu, Di; Liu, Wenjun

    2015-12-11

    Human influenza infections display a strongly seasonal pattern. However, whether H7N9 and H5N1 infections correlate with climate factors has not been examined. Here, we analyzed 350 cases of H7N9 infection and 47 cases of H5N1 infection. The spatial characteristics of these cases revealed that H5N1 infections mainly occurred in the South, Middle, and Northwest of China, while the occurrence of H7N9 was concentrated in coastal areas of East and South of China. Aside from spatial-temporal characteristics, the most adaptive meteorological conditions for the occurrence of human infections by these two viral subtypes were different. We found that H7N9 infections correlate with climate factors, especially temperature (TEM) and relative humidity (RHU), while H5N1 infections correlate with TEM and atmospheric pressure (PRS). Hence, we propose a risky window (TEM 4-14 °C and RHU 65-95%) for H7N9 infection and (TEM 2-22 °C and PRS 980-1025 kPa) for H5N1 infection. Our results represent the first step in determining the effects of climate factors on two different virus infections in China and provide warning guidelines for the future when provinces fall into the risky windows. These findings revealed integrated predictive meteorological factors rooted in statistic data that enable the establishment of preventive actions and precautionary measures against future outbreaks.

  12. Association of Mx1 Asn631 variant alleles with reductions in morbidity, early mortality, viral shedding, and cytokine responses in chickens infected with a highly pathogenic avian influenza virus.

    Science.gov (United States)

    Ewald, Sandra J; Kapczynski, Darrell R; Livant, Emily J; Suarez, David L; Ralph, John; McLeod, Scott; Miller, Carolyn

    2011-06-01

    Myxovirus-resistance (Mx) proteins are produced by host cells in response to type I interferons, and some members of the Mx gene family in mammals have been shown to limit replication of influenza and other viruses. According to an early report, chicken Mx1 variants encoding Asn at position 631 have antiviral activity, whereas variants with Ser at 631 lack activity in experiments evaluating Mx1 complementary DNA (cDNA) expressed ectopically in a cell line. We evaluated whether the Mx1 631 dimorphism influenced pathogenesis of highly pathogenic avian influenza virus (HPAIV) infection in chickens of two commercial broiler lines, each segregating for Asn631 and Ser631 variants. Following intranasal infection with HPAIV strain A/Chicken/Queretaro/14588-19/1995 H5N2, chickens homozygous for Asn631 allele were significantly more resistant to disease based on early mortality, morbidity, or virus shedding than Ser631 homozygotes. Higher amounts of splenic cytokine transcripts were observed in the Ser631 birds after infection, consistent with higher viral loads seen in this group and perhaps contributing to their higher morbidity. Nucleotide sequence determination of Mx1 cDNAs demonstrated that the Asn631 variants in the two chicken lines differed at several amino acid positions outside 631. In vitro experiments with a different influenza strain (low pathogenicity) failed to demonstrate an effect of Mx1 Asn631 on viral replication suggesting that in vivo responses may differ markedly from in vitro, or that choice of virus strain may be critical in demonstrating effects of chicken Mx1. Overall, these studies provide the first evidence that Mx1 has antiviral effects in chickens infected with influenza virus.

  13. Protection against H5N1 highly pathogenic avian and pandemic (H1N1) 2009 influenza virus infection in cynomolgus monkeys by an inactivated H5N1 whole particle vaccine.

    Science.gov (United States)

    Nakayama, Misako; Shichinohe, Shintaro; Itoh, Yasushi; Ishigaki, Hirohito; Kitano, Mitsutaka; Arikata, Masahiko; Pham, Van Loi; Ishida, Hideaki; Kitagawa, Naoko; Okamatsu, Masatoshi; Sakoda, Yoshihiro; Ichikawa, Takaya; Tsuchiya, Hideaki; Nakamura, Shinichiro; Le, Quynh Mai; Ito, Mutsumi; Kawaoka, Yoshihiro; Kida, Hiroshi; Ogasawara, Kazumasa

    2013-01-01

    H5N1 highly pathogenic avian influenza virus (HPAIV) infection has been reported in poultry and humans with expanding clade designations. Therefore, a vaccine that induces immunity against a broad spectrum of H5N1 viruses is preferable for pandemic preparedness. We established a second H5N1 vaccine candidate, A/duck/Hokkaido/Vac-3/2007 (Vac-3), in our virus library and examined the efficacy of inactivated whole particles of this strain against two clades of H5N1 HPAIV strains that caused severe morbidity in cynomolgus macaques. Virus propagation in vaccinated macaques infected with either of the H5N1 HPAIV strains was prevented compared with that in unvaccinated macaques. This vaccine also prevented propagation of a pandemic (H1N1) 2009 virus in macaques. In the vaccinated macaques, neutralization activity, which was mainly shown by anti-hemagglutinin antibody, against H5N1 HPAIVs in plasma was detected, but that against H1N1 virus was not detected. However, neuraminidase inhibition activity in plasma and T-lymphocyte responses in lymph nodes against H1N1 virus were detected. Therefore, cross-clade and heterosubtypic protective immunity in macaques consisted of humoral and cellular immunity induced by vaccination with Vac-3.

  14. Gambaran Sel Eosinofil, Monosit, dan Basofil Setelah Pemberian Spirulina pada Ayam yang Diinfeksi Virus Flu Burung (OBSERVATION OF EOSINOPHILS, MONOCYTES, AND BASOPHILS AFTER TREATED WITH SPIRULINA IN CHICKENS THAT INFECTED WITH AVIAN INFLUENZA VIRUS

    Directory of Open Access Journals (Sweden)

    Widya Paramita Lokapirnasari

    2015-05-01

    Full Text Available High Pathogenecity Avian Influenza (HPAI viruses have high virulence and can frequently causesudden death on birds. The aims of this research was to know the role of Spirulina to a number ofmonocytes and lymphocytes in the blood of chickens which infected with the H5N1 virus. This researchconsisted of three levels of treatment in which each level given Spirulina 0%, 10%, 20% in the fresh wateralgae as drinking water. Each treatment consisted of seven replicates, and the treatment was done sincethe chickens at age 19 until 44 days ( for 25 days. Artificial infection of the chickens with the virus waschallenged by using AI (H5N1 104 EID 50 (A/Ck/Indonesia/BL/03 with route to the respiratory tract (nosedrops 0,1 mL starting on day 19. The results showed that there were a significant difference (p<0.05 ontreatment that given Spirulina at doses of 0%, 10% and 20% for the number ofn monocytes, eosinophils,whereas no significant difference (p > 0.05 was observed in basophils.

  15. Editorial: Avian Research

    Institute of Scientific and Technical Information of China (English)

    Yong; Wang; Guangmei; Zheng

    2014-01-01

    <正>Welcome to Avian Research!This new journal is a continuation and enhancement of Chinese Birds,which has been and continues to be sponsored by the China Ornithological Society and Beijing Forestry University.In the four years since its inception,the original journal—the only one in China focusing on avian research—has published over 130 manuscripts,with authors from all continents across the world,garnering global respect in

  16. Microsatellite typing of Aspergillus flavus from clinical and environmental avian isolates

    OpenAIRE

    2013-01-01

    Aspergillosis is one of the most common causes of death in captive birds. Aspergillus fumigatus accounts for approximately 95 % of aspergillosis cases and Aspergillus flavus is the second most frequent organism associated with avian infections. In the present study, the fungi were grown from avian clinical samples (post-mortem lung material) and environmental samples (eggs, food and litter). Microsatellite markers were used to type seven clinical avian isolates and 22 environmental isolates o...

  17. Entomological study on transmission of avian malaria parasites in a zoological garden in Japan: bloodmeal identification and detection of avian malaria parasite DNA from blood-fed mosquitoes.

    Science.gov (United States)

    Ejiri, Hiroko; Sato, Yukita; Kim, Kyeong-Soon; Hara, Tatsuko; Tsuda, Yoshio; Imura, Takayuki; Murata, Koichi; Yukawa, Masayoshi

    2011-05-01

    Several species of captive and wild birds have been found to be infected with various avian blood protozoa in Japan. We investigated the prevalence and transmission of avian malaria parasite and determined the bloodmeal hosts of mosquitoes collected in a zoological garden in Tokyo, Japan, by using the polymerase chain reaction. In total, 310 unfed and 140 blood-fed mosquitoes of seven species were collected by using sweep nets and CDC traps. Bloodmeal identification indicated that mosquitoes had fed on 17 avian and five mammalian species, including captive animals. The results of avian malaria parasite detection from mosquitoes with avian bloodmeals indicated that Culex pipiens pallens Coquillet is a main vector of avian Plasmodium in the current study site and that some captive and wild birds could be infected with avian malaria parasites. Furthermore, the distances between the collection site of blood-fed mosquitoes and the locations of their blood-source captive animals were estimated. Most females with fresh bloodmeals were found within 40 m of caged animals, whereas half-gravid and gravid females were found between 10 and 350 m from caged host animals. We demonstrated that blood-fed mosquitoes can provide useful information regarding the mosquito vector species of avian malaria parasites and allows for noninvasive detection of the presence of avian malaria parasites in bird populations.

  18. The perfect burrow, but for what? Identifying local habitat conditions promoting the presence of the host and vector species in the Kazakh plague system

    NARCIS (Netherlands)

    Levick, Bethany; Laudisoit, Anne; Wilschut, Liesbeth; Addink, Elisabeth; Ageyev, Vladimir; Yeszhanov, Aidyn; Sapozhnikov, Valerij; Belayev, Alexander; Davydova, Tania; Eagle, Sally; Begon, Mike; Johnson, Christopher James

    2015-01-01

    Introduction: The wildlife plague system in the Pre-Balkhash desert of Kazakhstan has been a subject of study for many years. Much progress has been made in generating a method of predicting outbreaks of the disease (infection by the gram negative bacterium Yersinia pestis) but existing methods are

  19. Beyond an AFLP genome scan towards the identification of immune genes involved in plague resistance in Rattus rattus from Madagascar.

    Science.gov (United States)

    Tollenaere, C; Jacquet, S; Ivanova, S; Loiseau, A; Duplantier, J-M; Streiff, R; Brouat, C

    2013-01-01

    Genome scans using amplified fragment length polymorphism (AFLP) markers became popular in nonmodel species within the last 10 years, but few studies have tried to characterize the anonymous outliers identified. This study follows on from an AFLP genome scan in the black rat (Rattus rattus), the reservoir of plague (Yersinia pestis infection) in Madagascar. We successfully sequenced 17 of the 22 markers previously shown to be potentially affected by plague-mediated selection and associated with a plague resistance phenotype. Searching these sequences in the genome of the closely related species Rattus norvegicus assigned them to 14 genomic regions, revealing a random distribution of outliers in the genome (no clustering). We compared these results with those of an in silico AFLP study of the R. norvegicus genome, which showed that outlier sequences could not have been inferred by this method in R. rattus (only four of the 15 sequences were predicted). However, in silico analysis allowed the prediction of AFLP markers distribution and the estimation of homoplasy rates, confirming its potential utility for designing AFLP studies in nonmodel species. The 14 genomic regions surrounding AFLP outliers (less than 300 kb from the marker) contained 75 genes encoding proteins of known function, including nine involved in immune function and pathogen defence. We identified the two interleukin 1 genes (Il1a and Il1b) that share homology with an antigen of Y. pestis, as the best candidates for genes subject to plague-mediated natural selection. At least six other genes known to be involved in proinflammatory pathways may also be affected by plague-mediated selection.

  20. MiR-34b-5p Suppresses Melanoma Differentiation-Associated Gene 5 (MDA5) Signaling Pathway to Promote Avian Leukosis Virus Subgroup J (ALV-J)-Infected Cells Proliferaction and ALV-J Replication.

    Science.gov (United States)

    Li, Zhenhui; Luo, Qingbin; Xu, Haiping; Zheng, Ming; Abdalla, Bahareldin Ali; Feng, Min; Cai, Bolin; Zhang, Xiaocui; Nie, Qinghua; Zhang, Xiquan

    2017-01-01

    Avian leukosis virus subgroup J (ALV-J) is an oncogenic retrovirus that has a similar replication cycle to multiple viruses and therefore can be used as a model system for viral entry into host cells. However, there are few reports on the genes or microRNAs (miRNAs) that are responsible for the replication of ALV-J. Our previous miRNA and RNA sequencing data showed that the expression of miR-34b-5p was significantly upregulated in ALV-J-infected chicken spleens compared to non-infected chicken spleens, but melanoma differentiation-associated gene 5 (MDA5) had the opposite expression pattern. In this study, a dual-luciferase reporter assay showed that MDA5 is a direct target of miR-34b-5p. In vitro, overexpression of miR-34b-5p accelerated the proliferation of ALV-J-infected cells by inducing the progression from G2 to S phase and it promoted cell migration. Ectopic expression of MDA5 inhibited ALV-J-infected cell proliferation, the cell cycle and cell migration, and knockdown of MDA5 promoted proliferation, the cell cycle and migration. In addition, during ALV-J infections, MDA5 can detect virus invasion and it triggers the MDA5 signaling pathway. MDA5 overexpression can activate the MDA5 signaling pathway, and thus it can inhibit the mRNA and protein expression of the ALV-J env gene and it can suppress virion secretion. In contrast, in response to the knockdown of MDA5 by small interfering RNA (siRNA) or an miR-34b-5p mimic, genes in the MDA5 signaling pathway were significantly downregulated (P J env and the sample-to-positive ratio of virion in the supernatants were increased. This indicates that miR-34b-5p is able to trigger the MDA5 signaling pathway and affect ALV-J infections. Together, these results suggest that miR-34b-5p targets MDA5 to accelerate the proliferation and migration of ALV-J-infected cells, and it promotes ALV-J replication, via the MDA5 signaling pathway.

  1. Construction of an infectious cDNA clone of avian hepatitis E virus (avian HEV) recovered from a clinically healthy chicken in the United States and characterization of its pathogenicity in specific-pathogen-free chickens.

    Science.gov (United States)

    Kwon, Hyuk Moo; LeRoith, Tanya; Pudupakam, R S; Pierson, F William; Huang, Yao-Wei; Dryman, Barbara A; Meng, Xiang-Jin

    2011-01-27

    A genetically distinct strain of avian hepatitis E virus (avian HEV-VA strain) was isolated from a healthy chicken in Virginia, and thus it is important to characterize and compare its pathogenicity with the prototype strain (avian HEV-prototype) isolated from a diseased chicken. Here we first constructed an infectious clone of the avian HEV-VA strain. Capped RNA transcripts from the avian HEV-VA clone were replication-competent after transfection of LMH chicken liver cells. Chickens inoculated intrahepatically with RNA transcripts of avian HEV-VA clone developed active infection as evidenced by fecal virus shedding, viremia, and seroconversion. To characterize the pathogenicity, RNA transcripts of both avian HEV-VA and avian HEV-prototype clones were intrahepatically inoculated into the livers of chickens. Avian HEV RNA was detected in feces, serum and bile samples from 10/10 avian HEV-VA-inoculated and 9/9 avian HEV-prototype-inoculated chickens although seroconversion occurred only in some chickens during the experimental period. The histopathological lesion scores were lower for avian HEV-VA group than avian HEV-prototype group in the liver at 3 and 5 weeks post-inoculation (wpi) and in the spleen at 3 wpi, although the differences were not statistically significant. The liver/body weight ratio, indicative of liver enlargement, of both avian HEV-VA and avian HEV-prototype groups were significantly higher than that of the control group at 5 wpi. Overall, the avian HEV-VA strain still induces histological liver lesions even though it was isolated from a healthy chicken. The results also showed that intrahepatic inoculation of chickens with RNA transcripts of avian HEV infectious clone may serve as an alternative for live virus in animal pathogenicity studies.

  2. CCR5 polymorphism and plague resistance in natural populations of the black rat in Madagascar

    OpenAIRE

    Tollenaere, C., Pernechele, B., Mäkinen, H., Parratt, S., Nemeth, M., Kovacs, G., Levente, K. Tack, A.; Rahalison, L.; Ranjalahy, M.; Rahelinirina, S.; Duplantier, Jean-Marc; Brouat, Carine

    2008-01-01

    Madagascar remains one of the world's largest plague foci. The black rat, Rattus rattus, is the main reservoir of plague in rural areas. This species is highly susceptible to plague in plague-free areas (low-altitude regions), whereas rats from the plague focus areas (central highlands) have evolved a disease-resistance polymorphism. We used the candidate gene CCR5 to investigate the genetic basis of plague resistance in R. rattus. We found a unique non-synonymous substitution (H184R) in a fu...

  3. 禽流感病毒非结构蛋白NS1在感染和免疫中的作用%Roles of Avian Influenza Virus Non-structural 1 Protein in Infection and Immunity

    Institute of Scientific and Technical Information of China (English)

    路冰; 陈化兰; 包红梅; 王秀荣; 张秀英

    2011-01-01

    NS1蛋白(non-structural 1 protein)是目前发现的唯一的禽流感病毒非结构蛋白,它是一种多功能调节蛋白,对病毒的感染、复制和毒力具有重要的作用;该蛋白主要通过颉颃宿主干扰素及肿瘤坏死因子,抑制宿主蛋白的合成及调控感染细胞的凋亡来实现其作用.作者综述了NS1蛋白生物学特性及其在感染和免疫中作用的研究进展,为进一步研究NS1蛋白的特性及临床应用提供了参考.%NS1 (non-structural 1) protein is the unique non-structural protein found in avian influenza virus.It is a kind of multifunctional regulatory protein which plays a vital role in virus infection,replication and virulence.Its main function is antagonizing the host interferon and tumor necrosis factor,production inhibiting host protein synthesis as well as regulating apoptosis of infected cells.This paper reviews the latest research on the biological characteristics of NS1 protein and its role in infection and immunity which provide a reference for further research on NS1 protein's characteristics and clinical application.

  4. Prevalence and characteristics of hypoxic hepatitis in the largest single-centre cohort of avian influenza A(H7N9) virus-infected patients with severe liver impairment in the intensive care unit.

    Science.gov (United States)

    Zhang, YiMin; Liu, JiMin; Yu, Liang; Zhou, Ning; Ding, Wei; Zheng, ShuFa; Shi, Ding; Li, LanJuan

    2016-01-06

    Avian influenza A(H7N9) virus (A(H7N9)) emerged in February 2013. Liver impairment of unknown cause is present in 29% of patients with A(H7N9) infection, some of whom experience severe liver injury. Hypoxic hepatitis (HH) is a type of acute severe liver injury characterized by an abrupt, massive increase in serum aminotransferases resulting from anoxic centrilobular necrosis of liver cells. In the intensive care unit (ICU), the prevalence of HH is ∼1%-2%. Here, we report a 1.8% (2/112) incidence of HH in the largest single-centre cohort of ICU patients with A(H7N9) infection. Both HH patients presented with multiple organ failure (MOF) involving respiratory, cardiac, circulatory and renal failure and had a history of chronic heart disease. On admission, severe liver impairment was found. Peak alanine aminotransferase (ALT) and aspartate aminotransferase (AST) values were 937 and 1281 U/L, and 3117 and 3029 U/L, respectively, in the two patients. Unfortunately, both patients died due to deterioration of MOF. A post-mortem biopsy in case 1 confirmed the presence of centrilobular necrosis of the liver, and real-time reverse transcription polymerase chain reaction of A(H7N9)-specific genes was negative, which excluded A(H7N9)-related hepatitis. The incidence of HH in A(H7N9) patients is similar to that in ICU patients with other aetiologies. It seems that patients with A(H7N9) infection and a history of chronic heart disease with a low left ventricular ejection fraction on admission are susceptible to HH, which presents as a marked elevation in ALT at the time of admission.

  5. Lesions of the avian pancreas.

    Science.gov (United States)

    Schmidt, Robert E; Reavill, Drury R

    2014-01-01

    Although not well described, occasional reports of avian exocrine and endocrine pancreatic disease are available. This article describes the lesions associated with common diseases of the avian pancreas reported in the literature and/or seen by the authors.

  6. Discovery of a leptospirosis cluster amidst a pneumonic plague outbreak in a miners' camp in the Democratic Republic of the Congo.

    Science.gov (United States)

    Bertherat, Eric; Mueller, Melissa J; Shako, Jean-Christophe; Picardeau, Mathieu

    2014-02-07

    Conditions in the Democratic Republic of the Congo provide an ideal environment for leptospirosis and plague, both of which can cause severe pulmonary manifestations. In December 2004, an outbreak of lethal pneumonia occurred in a local mining camp, affecting 130 persons and killing 57 of them. Clinical signs, fast disease spread, and initial laboratory investigations suggested pneumonic plague. While leptospirosis had not recently been described in the region, it was considered as a differential diagnosis. Anti-Leptospira antibodies were detected by microscopic agglutination test (MAT). A confirmed case of leptospirosis was defined as having consistent clinical signs and any one of the following: seroconversion or four-fold increase in MAT titre for paired serum samples, or a MAT titre ≥ 1:400 for acute-phase serum samples. Twenty-nine of the 54 patients or convalescents tested for leptospirosis were seropositive. Two cases showed a confirmed infection for both plague and leptospirosis. While evidence supports the plague nature of this outbreak, the results suggest that some of the suspected plague cases might be due to leptospirosis. In any case, this diagnosis will have to be evoked in the future if a similar outbreak occurs in this region of Africa.

  7. CCR5 polymorphism and plague resistance in natural populations of the black rat in Madagascar.

    Science.gov (United States)

    Tollenaere, C; Rahalison, L; Ranjalahy, M; Rahelinirina, S; Duplantier, J-M; Brouat, C

    2008-12-01

    Madagascar remains one of the world's largest plague foci. The black rat, Rattus rattus, is the main reservoir of plague in rural areas. This species is highly susceptible to plague in plague-free areas (low-altitude regions), whereas rats from the plague focus areas (central highlands) have evolved a disease-resistance polymorphism. We used the candidate gene CCR5 to investigate the genetic basis of plague resistance in R. rattus. We found a unique non-synonymous substitution (H184R) in a functionally important region of the gene. We then compared (i) CCR5 genotypes of dying and surviving plague-challenged rats and (ii) CCR5 allelic frequencies in plague focus and plague-free populations. Our results suggested a higher prevalence of the substitution in resistant animals compared to susceptible individuals, and a tendency for higher frequencies in plague focus areas compared to plague-free areas. Therefore, the CCR5 polymorphism may be involved in Malagasy black rat plague resistance. CCR5 and other undetermined plague resistance markers may provide useful biological information about host evolution and disease dynamics.

  8. Genotyping, Orientalis-like Yersinia pestis, and plague pandemics.

    Science.gov (United States)

    Drancourt, Michel; Roux, Véronique; Dang, La Vu; Tran-Hung, Lam; Castex, Dominique; Chenal-Francisque, Viviane; Ogata, Hiroyuki; Fournier, Pierre-Edouard; Crubézy, Eric; Raoult, Didier

    2004-09-01

    Three pandemics have been attributed to plague in the last 1,500 years. Yersinia pestis caused the third, and its DNA was found in human remains from the second. The Antiqua biovar of Y. pestis may have caused the first pandemic; the other two biovars, Medievalis and Orientalis, may have caused the second and third pandemics, respectively. To test this hypothesis, we designed an original genotyping system based on intergenic spacer sequencing called multiple spacer typing (MST). We found that MST differentiated every biovar in a collection of 36 Y. pestis isolates representative of the three biovars. When MST was applied to dental pulp collected from remains of eight persons who likely died in the first and second pandemics, this system identified original sequences that matched those of Y. pestis Orientalis. These data indicate that Y. pestis caused cases of Justinian plague. The two historical plague pandemics were likely caused by Orientalis-like strains.

  9. [The spread of the plague: A sciento-historiographic review].

    Science.gov (United States)

    Cuadrada, Coral

    2015-01-01

    There is still uncertainty about the diagnosis and nature of the plague; some scholars have been forced to abandon certainties and be filled with doubts: from believing that the mediaeval Black Plague was, in reality, the bubonic plague (although with unusual characteristics) to stating that there is very little evidence to support a retro-diagnosis. This article looks at this in depth, not only reviewing the historiography but also giving new interpretations which question previous hypotheses through research on images of the time, comparing them to the most recent investigative data. Two primary sources are analysed: Renaissance treaties written by four Italian doctors: Michele Savonarola, Marsilio Ficino, Leonardo Fioravanti and Gioseffo Daciano; and iconography: an illustrated manuscript of the Decameron by Giovanni Boccaccio and a Hebrew Haggadah from the XIVth century. The results are compared to the most recent research on DNA and in micropaleontology.

  10. History of highly pathogenic avian influenza.

    Science.gov (United States)

    Alexander, D J; Brown, I H

    2009-04-01

    The most widely quoted date for the beginning of the recorded history of avian influenza (AI) is 1878, when researchers first differentiated a disease of poultry (initially known as fowl plague but later renamed highly pathogenic avian influenza) from other diseases with high mortality rates. Current evidence indicates that highly pathogenic AI (HPAI) viruses arise through mutation after low pathogenicity AI viruses of H5 or H7 subtype are introduced into poultry. Between 1877 and 1958, a number of epizootics of HPAI occurred in most parts of the world. From 1959 to 1995, the emergence of HPAI viruses was recorded on 15 occasions, but losses were minimal. In contrast, between 1996 and 2008, HPAI viruses emerged at least 11 times and four of these outbreaks involved many millions of birds. Events during this recent period are overshadowed by the current epizootic of HPAI due to an H5N1 virus that has spread throughout Asia and into Europe and Africa, affecting over 60 countries and causing the loss of hundreds of millions of birds. All sectors of the poultry population have been affected, but free-range commercial ducks, village poultry, live bird markets and fighting cocks seem especially significant in the spread of the virus. The role of wild birds has been extensively debated but it is likely that both wild birds and domestic poultry are responsible for its spread. Even without these H5N1 outbreaks, the period 1995 to 2008 will be considered significant in the history of HPAI because of the vast numbers of birds that died or were culled in three of the other ten epizootics during this time.

  11. Flying over an infected landscape: distribution of highly pathogenic avian influenza H5N1 risk in South Asia and satellite tracking of wild waterfowl

    Science.gov (United States)

    Gilbert, Marius; Newman, Scott H.; Takekawa, John Y.; Loth, Leo; Biradar, Chandrashekhar; Prosser, Diann J.; Balachandran, Sivananinthaperumal; Rao, Mandava Venkata Subba; Mundkur, Taej; Yan, Baoping; Xing, Zhi; Hou, Yuansheng; Batbayar, Nyambayar; Tseveenmayadag, Natsagdorj; Hogerwerf, Lenny; Slingenbergh, Jan; Xiao, Xiangming

    2010-01-01

    Highly pathogenic avian influenza (HPAI) H5N1 virus persists in Asia, posing a threat to poultry, wild birds, and humans. Previous work in Southeast Asia demonstrated that HPAI H5N1 risk is related to domestic ducks and people. Other studies discussed the role of migratory birds in the long distance spread of HPAI H5N1. However, the interplay between local persistence and long-distance dispersal has never been studied. We expand previous geospatial risk analysis to include South and Southeast Asia, and integrate the analysis with migration data of satellite-tracked wild waterfowl along the Central Asia flyway. We find that the population of domestic duck is the main factor delineating areas at risk of HPAI H5N1 spread in domestic poultry in South Asia, and that other risk factors, such as human population and chicken density, are associated with HPAI H5N1 risk within those areas. We also find that satellite tracked birds (Ruddy Shelduck and two Bar-headed Geese) reveal a direct spatio-temporal link between the HPAI H5N1 hot-spots identified in India and Bangladesh through our risk model, and the wild bird outbreaks in May,June,July 2009 in China(Qinghai Lake), Mongolia, and Russia. This suggests that the continental-scale dynamics of HPAI H5N1 are structured as a number of persistence areas delineated by domestic ducks, connected by rare transmission through migratory waterfowl.

  12. Protecting poultry workers from exposure to avian influenza viruses.

    Science.gov (United States)

    MacMahon, Kathleen L; Delaney, Lisa J; Kullman, Greg; Gibbins, John D; Decker, John; Kiefer, Max J

    2008-01-01

    Emerging zoonotic diseases are of increasing regional and global importance. Preventing occupational exposure to zoonotic diseases protects workers as well as their families, communities, and the public health. Workers can be protected from zoonotic diseases most effectively by preventing and controlling diseases in animals, reducing workplace exposures, and educating workers. Certain avian influenza viruses are potential zoonotic disease agents that may be transmitted from infected birds to humans. Poultry workers are at risk of becoming infected with these viruses if they are exposed to infected birds or virus-contaminated materials or environments. Critical components of worker protection include educating employers and training poultry workers about occupational exposure to avian influenza viruses. Other recommendations for protecting poultry workers include the use of good hygiene and work practices, personal protective clothing and equipment, vaccination for seasonal influenza viruses, antiviral medication, and medical surveillance. Current recommendations for protecting poultry workers from exposure to avian influenza viruses are summarized in this article.

  13. Rational design of avian metapneumovirus live attenuated vaccines by inhibiting viral messenger RNA cap methyltransferase

    Science.gov (United States)

    Avian metapneumovirus (aMPV), also known as avian pneumovirus or turkey rhinotracheitis, is a non-segmented negative-sense RNA virus belonging to the family of Paramyxoviridae, the subfamily Pneumovirinae, and the genus Metapneumovirus. aMPV is the causative agent of respiratory tract infection and ...

  14. Modelling the Innate Immune Response against Avian Influenza Virus in Chicken

    NARCIS (Netherlands)

    Hagenaars, T J; Fischer, E A J; Jansen, C A; Rebel, J M J; Spekreijse, D; Vervelde, L; Backer, J A; de Jong, M C M; Koets, A P

    2016-01-01

    At present there is limited understanding of the host immune response to (low pathogenic) avian influenza virus infections in poultry. Here we develop a mathematical model for the innate immune response to avian influenza virus in chicken lung, describing the dynamics of viral load, interferon-α, -β

  15. Modelling the innate immune response against avian influenza virus in chicken

    NARCIS (Netherlands)

    Hagenaars, T.J.; Fischer, E.A.J.; Jansen, C.A.; Rebel, J.M.J.; Spekreijse, D.; Vervelde, L.; Backer, J.A.; Jong, de M.C.M.; Koets, A.P.

    2016-01-01

    At present there is limited understanding of the host immune response to (low pathogenic) avian influenza virus infections in poultry. Here we develop a mathematical model for the innate immune response to avian influenza virus in chicken lung, describing the dynamics of viral load, interferon-α,

  16. Susceptibility of swine to H5 and H7 low pathogenic avian influenza viruses

    Science.gov (United States)

    The ability of pigs to become infected with low pathogenic avian influenza (LPAI) viruses from an avian reservoir, and then generate mammalian adaptable influenza A viruses (IAVs) is difficult to determine. Yet, it is an important link to understanding any relationship between LPAI virus ecology and...

  17. Comparative susceptibility of waterfowl and gulls to highly pathogenic avian influenza H5N1 virus

    Science.gov (United States)

    Wild avian species in the Orders Anseriformes (ducks, geese, swans) and Charadriiformes (gulls, terns, shorebirds) have traditionally been considered the natural reservoirs for avian influenza viruses (AIV) and morbidity or mortality is rarely associated with AIV infection in these hosts. However, ...

  18. Pathogenesis of avian influenza A (H5N1) viruses in pigs

    Science.gov (United States)

    Background. Genetic reassortment of avian influenza H5N1 viruses with currently circulating human influenza A strains is one possibility that could lead to efficient human-to-human transmissibility. Domestic pigs which are susceptible to infection with both human and avian influenza A viruses are o...

  19. Personal Protective Equipment and Risk for Avian Influenza (H7N3)

    OpenAIRE

    Morgan, Oliver; Kuhne, Mirjam; Nair, Pat; Verlander, Neville Q.; Preece, Richard; McDougal, Marianne; Zambon, Maria; Reacher, Mark

    2009-01-01

    An outbreak of avian influenza (H7N3) among poultry resulted in laboratory-confirmed disease in 1 of 103 exposed persons. Incomplete use of personal protective equipment (PPE) was associated with conjunctivitis and influenza-like symptoms. Rigorous use of PPE by persons managing avian influenza outbreaks may reduce exposure to potentially hazardous infected poultry materials.

  20. Transmission efficiency of two flea species (Oropsylla tuberculata cynomuris and Oropsylla hirsuta) involved in plague epizootics among prairie dogs.

    Science.gov (United States)

    Wilder, Aryn P; Eisen, Rebecca J; Bearden, Scott W; Montenieri, John A; Tripp, Daniel W; Brinkerhoff, R Jory; Gage, Kenneth L; Antolin, Michael F

    2008-06-01

    Plague, caused by Yersinia pestis, is an exotic disease in North America circulating predominantly in wild populations of rodents and their fleas. Black-tailed prairie dogs (Cynomys ludovicianus) are highly susceptible to infection, often experiencing mortality of nearly all individuals in a town as a result of plague. The fleas of black-tailed prairie dogs are Oropsylla tuberculata cynomuris and Oropsylla hirsuta. We tested the efficiency of O. tuberculata cynomuris to transmit Y. pestis daily from 24 to 96 h postinfection and compared it to previously collected data for O. hirsuta. We found that O. tuberculata cynomuris has over threefold greater transmission efficiency (0.18 infected fleas transmit Y. pestis at 24 h postinfection) than O. hirsuta (0.05 fleas transmit). Using a simple model of flea-borne transmission, we combine these laboratory measurements with field data on monthly flea loads to compare the seasonal vectorial capacity of these two flea species. Coinciding with seasonal patterns of flea abundance, we find a peak in potential for flea-borne transmission in March, during high O. tuberculata cynomuris abundance, and in September-October when O. hirsuta is common. Our findings may be useful in determining the timing of insecticidal dusting to slow plague transmission in black-tailed prairie dogs.

  1. Identification of B-cell epitopes in the capsid protein of avian hepatitis E virus (avian HEV) that are common to human and swine HEVs or unique to avian HEV.

    Science.gov (United States)

    Guo, H; Zhou, E-M; Sun, Z F; Meng, X-J; Halbur, P G

    2006-01-01

    Avian hepatitis E virus (avian HEV) was recently discovered in chickens from the USA that had hepatitis-splenomegaly (HS) syndrome. The complete genomic sequence of avian HEV shares about 50 % nucleotide sequence identity with those of human and swine HEVs. The open reading frame 2 (ORF2) protein of avian HEV has been shown to cross-react with human and swine HEV ORF2 proteins, but the B-cell epitopes in the avian HEV ORF2 protein have not been identified. Nine synthetic peptides from the predicted four antigenic domains of the avian HEV ORF2 protein were synthesized and corresponding rabbit anti-peptide antisera were generated. Using recombinant ORF2 proteins, convalescent pig and chicken antisera, peptides and anti-peptide rabbit sera, at least one epitope at the C terminus of domain II (possibly between aa 477-492) that is unique to avian HEV, one epitope in domain I (aa 389-410) that is common to avian, human and swine HEVs, and one or more epitopes in domain IV (aa 583-600) that are shared between avian and human HEVs were identified. Despite the sequence difference in ORF2 proteins between avian and mammalian HEVs and similar ORF2 sequence between human and swine HEV ORF2 proteins, rabbit antiserum against peptide 6 (aa 389-399) recognized only human HEV ORF2 protein, suggesting complexity of the ORF2 antigenicity. The identification of these B-cell epitopes in avian HEV ORF2 protein may be useful for vaccine design and may lead to future development of immunoassays for differential diagnosis of avian, swine and human HEV infections.

  2. Phage therapy of the white plague-like disease of Favia favus in the Red Sea

    Science.gov (United States)

    Atad, I.; Zvuloni, A.; Loya, Y.; Rosenberg, E.

    2012-09-01

    Coral disease is a major factor in the global decline of coral reefs. At present, there are no known procedures for preventing or treating infectious diseases of corals. Immunization is not possible because corals have a restricted adaptive immune system and antibiotics are neither ecologically safe nor practical in an open system. Thus, we tested phage therapy as an alternative therapeutic method for treating diseased corals. Phage BA3, specific to the coral pathogen Thalassomonas loyana, inhibited the progression of the white plague-like disease and transmission to healthy corals in the Gulf of Aqaba, Red Sea. Only one out of 19 (5 %) of the healthy corals became infected when placed near phage-treated diseased corals, whereas 11 out of 18 (61 %) healthy corals were infected in the no-phage control. This is the first successful treatment for a coral disease in the sea. We posit that phage therapy of certain coral diseases is achievable in situ.

  3. Avian Influenza A(H5N1) Virus in Egypt.

    Science.gov (United States)

    Kayali, Ghazi; Kandeil, Ahmed; El-Shesheny, Rabeh; Kayed, Ahmed S; Maatouq, Asmaa M; Cai, Zhipeng; McKenzie, Pamela P; Webby, Richard J; El Refaey, Samir; Kandeel, Amr; Ali, Mohamed A

    2016-03-01

    In Egypt, avian influenza A subtype H5N1 and H9N2 viruses are enzootic in poultry. The control plan devised by veterinary authorities in Egypt to prevent infections in poultry focused mainly on vaccination and ultimately failed. Recently, widespread H5N1 infections in poultry and a substantial increase in the number of human cases of H5N1 infection were observed. We summarize surveillance data from 2009 through 2014 and show that avian influenza viruses are established in poultry in Egypt and are continuously evolving genetically and antigenically. We also discuss the epidemiology of human infection with avian influenza in Egypt and describe how the true burden of disease is underestimated. We discuss the failures of relying on vaccinating poultry as the sole intervention tool. We conclude by highlighting the key components that need to be included in a new strategy to control avian influenza infections in poultry and humans in Egypt.

  4. The NlpD lipoprotein is a novel Yersinia pestis virulence factor essential for the development of plague.

    Directory of Open Access Journals (Sweden)

    Avital Tidhar

    Full Text Available Yersinia pestis is the causative agent of plague. Previously we have isolated an attenuated Y. pestis transposon insertion mutant in which the pcm gene was disrupted. In the present study, we investigated the expression and the role of pcm locus genes in Y. pestis pathogenesis using a set of isogenic surE, pcm, nlpD and rpoS mutants of the fully virulent Kimberley53 strain. We show that in Y. pestis, nlpD expression is controlled from elements residing within the upstream genes surE and pcm. The NlpD lipoprotein is the only factor encoded from the pcm locus that is essential for Y. pestis virulence. A chromosomal deletion of the nlpD gene sequence resulted in a drastic reduction in virulence to an LD(50 of at least 10(7 cfu for subcutaneous and airway routes of infection. The mutant was unable to colonize mouse organs following infection. The filamented morphology of the nlpD mutant indicates that NlpD is involved in cell separation; however, deletion of nlpD did not affect in vitro growth rate. Trans-complementation experiments with the Y. pestis nlpD gene restored virulence and all other phenotypic defects. Finally, we demonstrated that subcutaneous administration of the nlpD mutant could protect animals against bubonic and primary pneumonic plague. Taken together, these results demonstrate that Y. pestis NlpD is a novel virulence factor essential for the development of bubonic and pneumonic plague. Further, the nlpD mutant is superior to the EV76 prototype live vaccine strain in immunogenicity and in conferring effective protective immunity. Thus it could serve as a basis for a very potent live vaccine against bubonic and pneumonic plague.

  5. The clinico-pathological effects of chicken infected with highly pathogenic avian influenza in some farms located in East Java and West Java

    Directory of Open Access Journals (Sweden)

    R Damayanti

    2004-06-01

    Full Text Available The study was conducted to investigate the clinico-pathological features of highly contagious disease occurred in chicken located in East and West Java during the outbreak in September-October 2003. Six farms located in Districts of Surabaya, Malang and Blitar of East Java had been visited. They were mainly commercial layer, breeder layer and breeder broiler, which the population was between 14.000, 80.000, and aged 17-70 weeks. Where as five farms in West Java (Districts of Bogor, Bekasi and their surrounding areas were visited and consisted of commercial layer and breeder broiler, having population of 3000-16.000 and aged 11-53 weeks. Observation was made according to clinical, gross pathological and histopathological changes. Clinically, most of them had cyanotic wattle and comb and subcutaneous petechiation of non-feathered part of the legs. These were also seen in necropsy, accompanied by general circulatory disturbances in most organs: namely pectoral and thigh muscle, trachea, lungs, epicard, myocard, proventriculus, liver, kidney and ovary. In addition, the liver was congested, friable and necrotic in some parts. Histologically, hemorrhage and non suppurative inflammatory reaction were observed in the brain, skin (comb, wattle and non feathered leg, skeletal muscle, trachea, lung, heart, proventriculus, liver, kidney and ovary whereas vasculitis was found especially in the skin of the wattle and comb, brain and kidney. It is concluded that based on the clinicopathological findings the outbreak of poultry disease in East and West Java were attributed to highly pathogenic avian influenza.

  6. [Advance to the research of the climate factor effect on the distribution of plague].

    Science.gov (United States)

    Zhang, A P; Wei, R J; Xiong, H M; Wang, Z Y

    2016-05-01

    Plague is an anthropozoonotic disease caused by the Yersinia pestis ,which developed by many factors including local climate factors. In recent years, more and more studies on the effects of climate on plague were conducted. According to the researches, climate factors (mainly the rainfall and temperature) affected the development and distribution of plague by influencing the abundance of plague host animals and fleas index. The climate also affected the epidemic dynamics and the scope of plague. There were significant differences existing in the influence of climate on the palgue developed in the north and south China. In the two different plague epidemic systems, the solitary Daurian ground squirrel-flea-plague and the social Mongolian gerbil-flea-plague, the obvious population differences existed among the responses of the host animal to the climate changes. Although the internal relationship between the rainfall, the flea index, the density of rodents and the plague supported the nutritional cascade hypothesis, it can not prove that there is a clear causality between the occurrence of plague and rainfall. So the influence of climate factors on plague distribution can only be used for early forecasting and warning of the plague.

  7. Comparison of virulence factors and expression of specific genes between uropathogenic Escherichia coli and avian pathogenic E. coli in a murine urinary tract infection model and a chicken challenge model.

    Science.gov (United States)

    Zhao, Lixiang; Gao, Song; Huan, Haixia; Xu, Xiaojing; Zhu, Xiaoping; Yang, Weixia; Gao, Qingqing; Liu, Xiufan

    2009-05-01

    Avian pathogenic Escherichia coli (APEC) and uropathogenic E. coli (UPEC) establish infections in extraintestinal habitats of different hosts. As the diversity, epidemiological sources and evolutionary origins of extraintestinal pathogenic E. coli (ExPEC) are so far only partially defined, in the present study,100 APEC isolates and 202 UPEC isolates were compared by their content of virulence genes and phylogenetic groups. The two groups showed substantial overlap in terms of their serogroups, phylogenetic groups and virulence genotypes, including their possession of certain genes associated with large transmissible plasmids of APEC. In a chicken challenge model, both UPEC U17 and APEC E058 had similar LD(50), demonstrating that UPEC U17 had the potential to cause significant disease in poultry. To gain further information about the similarities between UPEC and APEC, the in vivo expression of 152 specific genes of UPEC U17 and APEC E058 in both a murine urinary tract infection (UTI) model and a chicken challenge model was compared with that of these strains grown statically to exponential phase in rich medium. It was found that in the same model (murine UTI or chicken challenge), various genes of UPEC U17 and APEC E058 showed a similar tendency of expression. Several iron-related genes were upregulated in the UTI model and/or chicken challenge model, indicating that iron acquisition is important for E. coli to survive in blood or the urinary tract. Based on these results, the potential for APEC to act as human UPEC or as a reservoir of virulence genes for UPEC should be considered. Further, this study compared the transcriptional profile of virulence genes among APEC and UPEC in vivo.

  8. Planning and executing a vaccination campaign against avian influenza.

    Science.gov (United States)

    Marangon, S; Cristalli, A; Busani, L

    2007-01-01

    Vaccination against avian influenza infection caused by H5 or H7 virus subtypes has been used on several occasions in recent years to control and in some cases eradicate the disease. In order to contain avian influenza infection effectively, immunization should be combined with a coordinated set of control and monitoring measures. The outcome of an immunization campaign depends on the territorial strategy; whereas the capacity of the veterinary services in developed countries permits enforcement of strategies aimed at eradicating avian influenza, many countries currently affected by highly pathogenic avian influenza (HPAI) H5N1 viruses have a limited veterinary infrastructure and a limited capacity to respond to such epidemics. In these countries, resources are still insufficient to conduct adequate surveillance for identification and reaction to avian influenza outbreaks when they occur. When properly applied in this scenario, immunization can reduce mortality and production losses. In the long term, immunization might also decrease the prevalence of infection to levels at which stamping-out and surveillance can be applied. Countries should adapt their immunization programmes to local conditions in order to guarantee their efficacy and sustainability. In the initial emergency phase, human resources can be mobilized, with reliance on personal responsibility and motivation, thus compensating for potential shortcomings in organization. A more appropriate allocation of resources must be pursued in the long term, remembering that biosecurity is the main component of an exit strategy and must always be improved.

  9. The Helper Activities of Different Avian Viruses for Propagation of Recombinant Avian Adeno-Associated Virus

    Institute of Scientific and Technical Information of China (English)

    WANG An-ping; SUN Huai-chang; WANG Jian-ye; WANG Yong-juan; YUAN Wei-feng

    2007-01-01

    To compare the helper activities of different avian viruses for propagation of recombinant avian adeno-associated virus (rAAAV), AAV-293 cells were cotransfected with the AAAV vector pAITR-GFP containing green fluorescent protein (GFP) gene, the AAAV helper vector pcDNA-ARC expressing the rep and cap genes, and the adenovirus helper vector pHelper expressing Ad5 E2A, E4, and VA-RNA genes. Chicken embryonic fibroblast (CEF) or chicken embryonic liver (CEL) cells were cotransfected with the AAAV vector and the AAAV helper vector, followed by infection with Marek's disease virus (MDV), avian adenovirus, chicken embryo lethal orphan (CELO) virus or infectious bursal disease virus (IBDV). Infectious rAAAV particles generated by the two strategies were harvested and titrated on CEF and CEL cells. A significantly higher viral titer was obtained with the helper activity provided by the pHelper vector than by MDV or CELO virus. Further experiments showed that rAAAV-mediated green fluorescent protein (gfp) expression was overtly enhanced by MDV or CELO virus super infection or treatment with sodium butyric acid, but not by IBDV super infection. These data demonstrated that MDV and CELO viruses could provide weak helper activity for propagation of rAAAV, and rAAAV-mediated transgene expression could be enhanced by super infection with the helper viruses.

  10. 阿拉善黄鼠疫源地鼠疫疫情动态分析%The epidemic process and dynamic analysis of plague in the natural plague focus of Alashan Citellus mongolicus umbratus

    Institute of Scientific and Technical Information of China (English)

    李兵; 王升文

    2011-01-01

    Objective To analyze the epidemic status of the natural plague focus of Alashan Citellus mongolicus umbratus, and to provide the basis for formulating the strategies of plague prevention and control. Methods According to the surveillance data of rodent, flea, Y. Pestis from 1999 to 2008, relationship between the constituent elements and the epidemic status quo in the plague foci of Alashan Citellus mongolicus umbratus was analyzed. Results There was no outbreaks of human plague epidemic in the Alashan Citellus mongolicus umbratus natural plague focus from 1999 to 2008. The number of host positive serums was 34, the maximum titer attain to 1: 2 560, the Alashan Citellus mongolicus umbratus density was 1. 50, the infected flea rate of body flea was 62.99% , the body flea index was 1. 96, the holes flea index was 0. 33 , the nest flea index was 5.1. Conclusions Animals plague had occurred in the part of plague focus of Alashan Citellus mongolicus umbratus from 1999 to 2004. From 2004 until now, the epidemic tendency of animals plague was inactively state, but Citellus mongolicus umbratus density and its flea index is much higher than the standards of plague control, it should be still attached great importance.%目的 探讨分析阿拉善黄鼠疫源地鼠疫流行现状,为今后制定防控对策提供依据.方法 通过归纳1999~ 2008年宿主、媒介、病原等监测数据,分析疫源地构成因素之间的相互关系与现状.结果 1999~2008年阿拉善黄鼠疫源地未发生人间鼠疫疫情;检出动物阳性血清34份,最高滴度1∶2560;阿拉善黄鼠密度1.50只/hm2,体蚤染蚤率为62.99%,体蚤指数为1.96,洞干蚤指数为0.33,巢蚤指数5.1.结论 1999~ 2004年阿拉善黄鼠鼠疫疫源地局部有动物鼠疫流行.从2004年截止目前,鼠疫动物流行病处于静息状态,但黄鼠密度和其蚤指数远高于鼠疫控制标准,仍然要高度重视鼠疫防控工作.

  11. Variations in virulence of avian pathogenic Escherichia coli demonstrated by the use of a new in vivo infection model

    DEFF Research Database (Denmark)

    Pors, Susanne Elisabeth; Olsen, Rikke Heidemann; Christensen, Jens Peter

    2014-01-01

    Salpingitis and peritonitis are common pathological manifestations observed in egg-laying hens. To improve methods to study these conditions, a surgical model was developed. Initially, eighteen white layers underwent laparotomy with subsequent inoculation of ink, bacteria or sterile broth directly...... into the oviduct. Eight birds inoculated with 0.1 ml blue ink were euthanized immediately after inoculation and the specific site of inoculation was assessed. In all birds, ink was injected into the oviduct between five and seven cm cranial to the isthmus. To demonstrate the use of this approach to cause infection...... of the oviduct, five birds were inoculated with 8.6 × 10(6)CFU of a clinical Escherichia coli isolate. Five control birds received broth with no bacteria. Both infected and control birds were euthanized after 48 h followed by a post mortem examination. Infected birds showed diffuse fibrino-purulent peritonitis...

  12. Second Language Teacher Education: The Problems That Plague Us.

    Science.gov (United States)

    Tedick, Diane J.; Walker, Constance L.

    1994-01-01

    A discussion of why change is needed in second-language teacher education considers five problems that plague the profession: lack of consideration of first- and second-language interdependence; fragmentation/isolation of language arts fields; view of language as "object;" focus on methodology; and failure to connect language and culture. (80…

  13. Plague Epidemic s in Syria b etween XIII - XV. Centuries

    Directory of Open Access Journals (Sweden)

    Esra ATMACA

    2015-07-01

    Full Text Available Epidemic diseases that cause mass death has been one of the greatest fears of the society in the past century Usually due to poor living conditions, poverty, the inadequate treatment. Plague is one of them. Plague word is sometimes used synonymously with t he word tâûn, sometimes considered to be a greater sense of the Word plague. These outbreaks occured repeatedly in human society and many times occured between XIII - XV. centuries. Our research aims to examine the plague occured in Syria in the Mamluk state domination discussed period. One of the outbreaks have occured in the period between the years 1347 - 1351. Epidemic was looming at the same time with the European named the black death or large extinction. Many people have been killed in Syria as in other places where the epidemic has spread. Rumors about them are given in the source is situated in the form of the issuance of the number of people who died in one day and sometimes the total number of deaths took place at a given date range. In this study, we aimed to determine which is more severe than the others in the outbreak, to assess the rumor about the number of deaths from this cause, to reveal the difficulties of the funeral of the dead, to uncover practices that people do to get rid of this disease.

  14. A curve of thresholds governs plague epizootics in Central Asia

    DEFF Research Database (Denmark)

    Reijniers, Jonas; Davis, Stephen; Begon, Mike

    2012-01-01

    , it is common to assume a threshold defined by the ratio of vector and host abundances. Here, we show in contrast, both from field data and model simulations, that for plague (Yersinia pestis) in Kazakhstan, the invasion threshold quantity is based on the product of its host (Rhombomys opimus) and vector...

  15. Infections

    Science.gov (United States)

    ... Infections Adenovirus Bronchiolitis Campylobacter Infections Cat Scratch Disease Cellulitis Chickenpox Chlamydia Cold Sores Common Cold Coxsackievirus Infections Croup Cytomegalovirus (CMV) Dengue Fever Diphtheria E. Coli ...

  16. 规模化肉鸡场常见呼吸道病原体感染状况调查%Epidemic Investigation for the Infection Avian Respiratory Disease Pathogens from a Large-scale Chicken Farm

    Institute of Scientific and Technical Information of China (English)

    朱明霞; 牛玉娟; 马海营; 吕传位; 张清林; 刘思当

    2015-01-01

    呼吸道疾病尤其是常见的禽流感、新城疫、传染性支气管炎是危害养鸡业最严重的疾病之一。为了解肉鸡初期呼吸道病病原体的感染状况,从2万孵化的鸡胚中采集了210枚弱、死胚样品及5日龄有呼吸道症状的48只病死鸡。用 RT-PCR 方法对这两批样品进行了 H9N2亚型禽流感病毒(H9N2AIV)、新城疫病毒(NDV)、传染性支气管炎病毒(IBV)感染状况的检测,又将5日龄的雏鸡进行了大肠杆菌(Escherichia coli)及沙门氏菌(Salmonella spp.)分离鉴定,分析检出率。结果表明,在210枚鸡胚样品中 H9N2 AIV、NDV 和 IBV 的检出率分别为3.81%,21.9%和23.8%,弱、死胚样品常见呼吸道病病毒感染率高达49.51%。5日龄雏鸡样品中 H9N2AIV、NDV、IBV、E. coli 和 S. spp.的检出率分别为45.8%,37.5%、10.4%、54.2%和8.3%,未发现3种病毒共感染的现象,但是病毒与细菌的共感染率达58.3%,主要是大肠杆菌与病毒的双重感染。呼吸道病毒一般能将鸡胚在孵化过程中致死,但若含病毒的鸡胚没能死亡,雏鸡出壳后发育到一定时期(母源抗体衰竭后)所含病毒会大量复制,进而发生相应的呼吸道疾病,在鸡群中迅速传播,并继发其他细菌性疾病,造成鸡群大批死亡,这是肉鸡中后期呼吸道疾病日益严重的重要原因。%Avian respiratory infection plays a prominent role in damaging the poultry industry, especially the Avian flu, Newcastle disease and chicken infectious bronchitis. 210 lung samples of dead or weak broiler embryo and 48 lung and liver samples of broilers with respiratory symptoms were collected from a large-scale broiler farm, and then RT-PCR was used to detect H9N2 subtype of Avian influenza virus (H9N2 AIV), Newcastle disease virus (NDV) and infectious bronchitis virus (IBV), Escherichia coli and Salmonella spp. were separated from 48 chicks. The results show that the detection rates

  17. 江西省2004~2005年禽流感(H5N1)高危暴露人群感染状况调查%INVESTIGATION ON AVIAN INFLUENZA (H5N1) INFECTION OF HIGH-RISK EXPOSURE GROUPS IN JIANGXI PROVINCE FROM 2004-2005

    Institute of Scientific and Technical Information of China (English)

    程慧健; 袁辉; 宗俊; 王健; 潘欢弘

    2011-01-01

    [Objective] To know avian influenza HSN1 infection of close contacts. [Methods] We found 204 close contacts with animal and human avian influenza from 2004-2005, surveyed their exposure ways, and collected 5ml venous blood from every close contact to test avian influenza H5N1 antibody through horse blood hemagglutination inhibition test and the micro-neutralization test [Results] In close contacts, there were 66.2% fanners, 13.2% students and 1.9% medical staffs. 73% of persons contacted with live poultry of the place that occurred animal avian influenza, 54.4% of persons contacted sick and dead poultry, 12.7% had history of exposure to human avian influenza. During contact process, these close contacts were up to only 16.2% of person taking some protective measures, and the protection was not standardized. Through testing their serum specimens, all these close contacts' H5N1 antibodies were negative. [Conclusion] All close contacts with animal and human avian influenza are not been infected with H5N1 in Jiangxi province from 2004-2005.%[目的]了解江西省H5N1禽流感密切接触者感染状况.[方法]调查2004~2005年禽流感和人禽流感疫情的密切接触者204人的暴露方式,采集静脉血5ml,进行马血球血凝抑制试验和微量中和试验,检测禽流感H5N1抗体水平.[结果]被调查的密切接触者农民占66.2%,学生占13.2%,医护人员占1.9%.73%的人接触过疫点内活禽,54.4%的人接触过病死禽,12.7%的人有禽流感患者接触史,接触过程中,最多只有16.2%的人采取了一些防护措施,且防护不规范.经检测,所有密切接触者血清标本禽流感H5N1抗体阴性.[结论]该省2004~2005年间禽流感和人间禽流感疫情的密切接触者均未感染H5N1.

  18. Practical disinfection chemicals for fishing and crayfishing gear against crayfish plague transfer

    Directory of Open Access Journals (Sweden)

    Jussila J.

    2014-01-01

    Full Text Available We tested four commercial disinfectants against crayfish plague (Aphanomyces astaci spores in both aquatic solutions and with material mimicking fishing and crayfishing gear, e.g. traps, ropes, mesh, etc. The tested disinfectants were Proxitane®5:14, Proxitane®12:20, Wofasteril®E400, Virkon®S and hydrogen peroxide. The effects of the chemicals were initially tested in liquid zoospore cultures and the effective concentrations were then further tested using clean and dirty model materials (PP sheet, nylon rope, cotton fabric contaminated with A. astaci spore solutions. The disinfectants effective against infective crayfish plague spores with both clean and dirty model materials were Proxinate®5:14 (effective concentration was 30 mg·L-1 of PAA and Virkon®S (3 g·L-1, while Proxinate®12:20 (10 mg·L-1 of PAA and Wofasteril®E400 (30 mg·L-1 of PAA worked only with clean model materials. Hydrogen peroxide was not effective in the tested concentrations and conditions. Based on the results, the disinfectants most suitable for the fishing and crayfishing gear disinfection would be Proxitane®5:14 and Virkon®S, with the condition that all the gear should be thoroughly cleaned of organic matter to ensure inactivation of A. astaci spores.

  19. Levofloxacin cures experimental pneumonic plague in African green monkeys.

    Directory of Open Access Journals (Sweden)

    Robert Colby Layton

    Full Text Available BACKGROUND: Yersinia pestis, the agent of plague, is considered a potential bioweapon due to rapid lethality when delivered as an aerosol. Levofloxacin was tested for primary pneumonic plague treatment in a nonhuman primate model mimicking human disease. METHODS AND RESULTS: Twenty-four African Green monkeys (AGMs, Chlorocebus aethiops were challenged via head-only aerosol inhalation with 3-145 (mean = 65 50% lethal (LD(50 doses of Y. pestis strain CO92. Telemetered body temperature >39 °C initiated intravenous infusions to seven 5% dextrose controls or 17 levofloxacin treated animals. Levofloxacin was administered as a "humanized" dose regimen of alternating 8 mg/kg and 2 mg/kg 30-min infusions every 24-h, continuing until animal death or 20 total infusions, followed by 14 days of observation. Fever appeared at 53-165 h and radiographs found multilobar pneumonia in all exposed animals. All control animals died of severe pneumonic plague within five days of aerosol exposure. All 16 animals infused with levofloxacin for 10 days survived. Levofloxacin treatment abolished bacteremia within 24 h in animals with confirmed pre-infusion bacteremia, and reduced tachypnea and leukocytosis but not fever during the first 2 days of infusions. CONCLUSION: Levofloxacin cures established pneumonic plague when treatment is initiated after the onset of fever in the lethal aerosol-challenged AGM nonhuman primate model, and can be considered for treatment of other forms of plague. Levofloxacin may also be considered for primary presumptive-use, multi-agent antibiotic in bioterrorism events prior to identification of the pathogen.

  20. Genetic diversity of avian influenza A (H10N8) virus in live poultry markets and its association with human infections in China.

    Science.gov (United States)

    Liu, Mingbin; Li, Xiaodan; Yuan, Hui; Zhou, Jianfang; Wu, Jingwen; Bo, Hong; Xia, Wen; Xiong, Ying; Yang, Lei; Gao, Rongbao; Guo, Junfeng; Huang, Weijuan; Zhang, Ye; Zhao, Xiang; Zou, Xiaohui; Chen, Tao; Wang, Dayan; Li, Qun; Wang, ShiWen; Chen, Shengen; Hu, Maohong; Ni, Xiansheng; Gong, Tian; Shi, Yong; Li, Jianxiong; Zhou, Jun; Cai, Jun; Xiao, Zuke; Zhang, Wei; Sun, Jian; Li, Dexin; Wu, Guizhen; Feng, Zijian; Wang, Yu; Chen, Haiying; Shu, Yuelong

    2015-01-15

    Following the first human infection with the influenza A (H10N8) virus in Nanchang, China in December 2013, we identified two additional patients on January 19 and February 9, 2014. The epidemiologic, clinical, and virological data from the patients and the environmental specimen collected from 23 local live poultry markets (LPMs) were analyzed. The three H10N8 cases had a history of poultry exposure and presented with high fever (>38°C), rapidly progressive pneumonia and lymphopenia. Substantial high levels of cytokines and chemokines were observed. The sequences from an isolate (A/Environment/Jiangxi/03489/2013 [H10N8]) in an epidemiologically linked LPM showed highly identity with human H10N8 virus, evidencing LPM as the source of human infection. The HA and NA of human and environmental H10N8 isolates showed high identity (99.1-99.9%) while six genotypes with internal genes derived from H9N2, H7N3 and H7N9 subtype viruses were detected in environmental H10N8 isolates. The genotype of the virus causing human infection, Jiangxi/346, possessed a whole internal gene set of the A/Environment/Jiangxi/10618/2014(H9N2)-like virus. Thus, our findings support the notion that LPMs can act as both a gene pool for the generation of novel reassortants and a source for human infection, and intensive surveillance and management should therefore be conducted.

  1. Avian influenza H5N1: an update on molecular pathogenesis

    Institute of Scientific and Technical Information of China (English)

    WANG HongLiang; JIANG ChengYu

    2009-01-01

    Avian influenza A virus constitutes a large threat to human health. Recent outbreaks of highly patho-genic avian influenza H5N1 virus in poultry and in humans have raised concerns that an influenza pandemic will occur in the near future. Transmission from avian species to humans remains sporadic, but the mortality associated with human infection is very high (about 62%). To date, there are no effec-tive therapeutic drugs or a prophylactic vaccines available, which means that there is still a long way to go before we can eradicate or cure avian influenza. This review focuses on the molecular pathogenesis of avian influenza H5N1 virus infection. An understanding of the viral pathogenesis may facilitate the development of novel treatments or effective eradication of this fatal disease.

  2. Avian influenza H5N1: an update on molecular pathogenesis

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Avian influenza A virus constitutes a large threat to human health. Recent outbreaks of highly pathogenic avian influenza H5N1 virus in poultry and in humans have raised concerns that an influenza pandemic will occur in the near future. Transmission from avian species to humans remains sporadic, but the mortality associated with human infection is very high (about 62%). To date, there are no effective therapeutic drugs or a prophylactic vaccines available, which means that there is still a long way to go before we can eradicate or cure avian influenza. This review focuses on the molecular pathogenesis of avian influenza H5N1 virus infection. An understanding of the viral pathogenesis may facilitate the development of novel treatments or effective eradication of this fatal disease.

  3. Avian influenza control strategies

    Science.gov (United States)

    Control strategies for avian influenza in poultry vary depending on whether the goal is prevention, management, or eradication. Components used in control programs include: 1) education which includes communication, public awareness, and behavioral change, 2) changes to production and marketing sys...

  4. Global Dynamics of Avian Influenza Epidemic Models with Psychological Effect

    Directory of Open Access Journals (Sweden)

    Sanhong Liu

    2015-01-01

    Full Text Available Cross-sectional surveys conducted in Thailand and China after the outbreaks of the avian influenza A H5N1 and H7N9 viruses show a high degree of awareness of human avian influenza in both urban and rural populations, a higher level of proper hygienic practice among urban residents, and in particular a dramatically reduced number of visits to live markets in urban population after the influenza A H7N9 outbreak in China in 2013. In this paper, taking into account the psychological effect toward avian influenza in the human population, a bird-to-human transmission model in which the avian population exhibits saturation effect is constructed. The dynamical behavior of the model is studied by using the basic reproduction number. The results demonstrate that the saturation effect within avian population and the psychological effect in human population cannot change the stability of equilibria but can affect the number of infected humans if the disease is prevalent. Numerical simulations are given to support the theoretical results and sensitivity analyses of the basic reproduction number in terms of model parameters that are performed to seek for effective control measures for avian influenza.

  5. The challenges of avian influenza virus:mechanism,epidemiology and control

    Institute of Scientific and Technical Information of China (English)

    George; F.GAO; Pang-Chui; SHAW

    2009-01-01

    Early 2009, eight human infection cases of H5N1 highly pathogenic avian influenza (HPAI) virus, with 5 death cases, were reported in China. This again made the world alert on a possible pandemic worldwide, probably caused by

  6. Avian Influenza Surveillance and Disease Contingency Plan for Prime Hook National Wildlife Refuge 2006

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — With Avian Influenza, a nonclinical viral infection, becoming a growing concern for wild bird populations in North America and the United States, it has become...

  7. [A(H5N1) and A(H7N9) avian influenza: the H7N9 avian influenza outbreak of 2013].

    Science.gov (United States)

    Wang, Quan; Yao, Kai-Hu

    2013-06-01

    influenza virus can infect humans and cause disease. The clinical presentation of human infection is usually mild, but the infection caused by A(H5N1) avian influenza virus occurring initially in Hongkong in 1997 or the A(H7N9) virus isolated first at the beginning of this year in China is severe and characterized by high mortality. The mortality rate of adolescents and children caused by H5N1 avian influenza is lower than that of adults and the younger the child the lower the mortality rate. A few pediatric H7N9 avian influenza cases recovered soon after treatment. A child was determined to be a H7N9 avian influenza virus carrier. These findings suggested that the pediatric H7N9 avian influenza infection was mild. It is very important to start anti-virus treatment with oseltamivir as early as possible in cases of avian influenza infection is considered. Combined therapy, including respiratory and circulatory support and inhibiting immunological reaction, is emphasized in the treatment of severe cases.

  8. A diarrheic chicken simultaneously co-infected with multiple picornaviruses: Complete genome analysis of avian picornaviruses representing up to six genera.

    Science.gov (United States)

    Boros, Ákos; Pankovics, Péter; Adonyi, Ádám; Fenyvesi, Hajnalka; Day, J Michael; Phan, Tung Gia; Delwart, Eric; Reuter, Gábor

    2016-02-01

    In this study all currently known chicken picornaviruses including a novel one (chicken phacovirus 1, KT880670) were identified by viral metagenomic and RT-PCR methods from a single specimen of a diarrheic chicken suffering from a total of eight picornavirus co-infections, in Hungary. The complete genomes of six picornaviruses were determined and their genomic and phylogenetic characteristics and UTR RNA structural models analyzed in details. Picornaviruses belonged to genera Sicinivirus (the first complete genome), Gallivirus, Tremovirus, Avisivirus and "Orivirus" (two potential genotypes). In addition, the unassigned phacoviruses were also detected in multiple samples of chickens in the USA. Multiple co-infections promote and facilitate the recombination and evolution of picornaviruses and eventually could contribute to the severity of the diarrhea in chicken, in one of the most important food sources of humans.

  9. 新型H7N9禽流感中医证候特点分析%Specialties of traditional Chinese medicine syndrome of novel H7N9 avian influenza infection

    Institute of Scientific and Technical Information of China (English)

    陈晓蓉; 陆云飞; 杨宗国; 王强; 徐庆年; 汤伯宗

    2013-01-01

    Objective:This study aims to analyze the specialties of traditional Chinese medicine (TCM) syndromes of novel H7N9 avian influenza infection.Methods:According to the analysis of TCM syndromes,tongue pictures and pulse,we try to conclude the clinical TCM syndromes of novel H7N9 infection.Results:①More than half of the 18 H7N9-infected patients suffered from fever (88.9%),cough (77.8%),expectoration (55.6%),fatigue (50.0%),poor appetite (83.3%),dry throat (72.2%),thirst (72.2%),breathlessness (66.7%),chest tightness (66.7%) and month bitter (61.1%).②Most of the 18 H7N9-infected patients had red tongue proper or deep red tongue proper.The distribution of tongue coats were thick and yellow (44.4%),thin and yellow (55.6%),yellow greasy fur (22.2%),dry and yellow (33.3%),with little fluid on tongue surface (55.6%),even dry tongue surface (33.3%).Tready and rapid were the main features of the pulse in H7N9-infected patients.Conclusion:Most of the H7N9-infected patients suffered from red or deep red tongue picture with yellow tongue coats,and tready pulse and rapid pulse.The TCM pathogens of H7N9 infection were mainly qi system syndrome and ying system syndrome,or wei-qi system syndrome,rarely with Wei system syndrome.%目的:分析新型H7N9禽流感的中医临床证候特点.方法:通过对18例H7N9感染者的中医证候、舌象、脉象的分析,总结新型H7N9禽流感可能存在的中医临床症候群.结果:①18例H7N9患者中50%以上患者发病时存在发热(88.9%)、咳嗽(77.8%)、咳痰(55.6%)、乏力(50.0%)、纳差(83.3%)、咽干(72.2%)、口渴(72.2%)、喘促(66.7%)、胸闷(66.7%)及口苦(61.1%)等证候.②18例H7N9患者中舌质多为红(77.8%)、绛(16.7%),舌苔多黄,其中厚苔、薄苔、腻苔与焦苔分别占44.4%,55.6%,22.2%,33.3%.舌面津液以少津(55.6%)、干燥(33.3%)表现为主.脉象以细(61.1%)、数脉(55.6%)为主.结论:H7N9禽流感

  10. Predicting Potential Risk Areas of Human Plague for the Western Usambara Mountains, Lushoto District, Tanzania

    DEFF Research Database (Denmark)

    Neerinckx, Simon; Peterson, A Townsend; Gulinck, Hubert

    2010-01-01

    A natural focus of plague exists in the Western Usambara Mountains of Tanzania. Despite intense research, questions remain as to why and how plague emerges repeatedly in the same suite of villages. We used human plague incidence data for 1986-2003 in an ecological-niche modeling framework...... to explore the geographic distribution and ecology of human plague. Our analyses indicate that plague occurrence is related directly to landscape-scale environmental features, yielding a predictive understanding of one set of environmental factors affecting plague transmission in East Africa. Although many...... environmental variables contribute significantly to these models, the most important are elevation and Enhanced Vegetation Index derivatives. Projections of these models across broader regions predict only 15.5% (under a majority-rule threshold) or 31,997 km2 of East Africa as suitable for plague transmission...

  11. Geographic distribution and ecological niche of plague in sub-Saharan Africa

    DEFF Research Database (Denmark)

    Neerinckx, Simon B; Peterson, Andrew T; Gulinck, Hubert

    2008-01-01

    Background Plague is a rapidly progressing, serious illness in humans that is likely to be fatal if not treated. It remains a public health threat, especially in sub-Saharan Africa. In spite of plague's highly focal nature, a thorough ecological understanding of the general distribution pattern...... of plague across sub-Saharan Africa has not been established to date. In this study, we used human plague data from sub-Saharan Africa for 1970-2007 in an ecological niche modeling framework to explore the potential geographic distribution of plague and its ecological requirements across Africa. Results We...... predict a broad potential distributional area of plague occurrences across sub-Saharan Africa. General tests of model's transferability suggest that our model can anticipate the potential distribution of plague occurrences in Madagascar and northern Africa. However, generality and predictive ability tests...

  12. Antigenic characterization of avian influenza H9 subtype isolated from desi and zoo birds

    Directory of Open Access Journals (Sweden)

    Farrukh Saleem

    2011-08-01

    Full Text Available Avian influenza is a viral infection which affects mainly the respiratory system of birds. The H9N2 considered as low pathogenic avian influenza (LPAI virus and continuously circulating in poultry flocks causing enormous economic losses to poultry industry of Pakistan. As these viruses have RNA genome and their RNA polymerase enzyme lacks proof reading activity which resulted in spontaneous mutation in surface glycoproteins (HA and NA and reassortment of their genomic segments results in escape from host immune response produced by the vaccine. Efforts made for the isolation and identification of avian influenza virus from live desi and zoo birds of Lahore and performed antigenic characterization. The local vaccines although gives a little bit less titer when we raise the antisera against these vaccines but their antisera have more interaction with the local H9 subtype antigen so it gives better protective immune response. Infected chicken antisera are more reactive as compare to rabbit antisera. This shows that our isolates have highest similarity with the currently circulating viruses. These results guided us to devise a new control strategy against avian influenza viral infections. The antigenic characterization of these avian influenza isolates helped us to see the antigenic differences between the isolates of this study and H9 subtype avian influenza viruses used in vaccines. Therefore, this study clearly suggests that a new local H9 subtype avian influenza virus should be used as vaccinal candidate every year for the effective control of influenza viral infections of poultry.

  13. A chaotic model for the plague epidemic that has occurred in Bombay at the end of the 19th century

    Science.gov (United States)

    Mangiarotti, Sylvain

    2015-04-01

    The plague epidemic that has occurred in Bombay at the end of the 19th century was detected in 1896. One year before, an Advisory Committee had been appointed by the Secretary of State for India, the Royal Society, and the Lister Institute. This Committee made numerous investigations and gathered a large panel of data including the number of people attacked and died from the plague, records of rat and flea populations, as well as meteorological records of temperature and humidity [1]. The global modeling technique [2] aims to obtain low dimensional models able to simulate the observed cycles from time series. As far as we know, this technique has been tried only to one case of epidemiological analysis (the whooping cough infection) based on a discrete formulation [3]. In the present work, the continuous time formulation of this technique is used to analyze the time evolution of the plague epidemic from this data set. One low dimensional model (three variables) is obtained exhibiting a limit cycle of period-5. A chaotic behavior could be derived from this model by tuning the model parameters. It provides a strong argument for a dynamical behavior that can be approximated by low dimensional deterministic equations. This model also provides an empirical argument for chaos in epidemics. [1] Verjbitski D. T., Bannerman W. B. & Kápadiâ R. T., 1908. Reports on Plague Investigations in India (May,1908), The Journal of Hygiene, 8(2), 161 -308. [2] Mangiarotti S., Coudret R., Drapeau L. & Jarlan L., 2012. Polynomial search and Global modelling: two algorithms for modeling chaos. Physical Review E, 86(4), 046205. [3] Boudjema G. & Cazelles B., 2003. Extraction of nonlinear dynamics from short and noisy time series. Chaos, Solitons and Fractals, 12, 2051-2069.

  14. Access to health information may improve behavior in preventing Avian influenza among women

    Directory of Open Access Journals (Sweden)

    Ajeng T. Endarti

    2011-02-01

    Full Text Available Background: Improving human behavior toward Avian influenza may lessen the chance to be infected by Avian influenza. This study aimed to identify several factors influencing behavior in the community.Method: A cross-sectional study was conducted in July 2008. Behavior regarding Avian influenza was measured by scoring the variables of knowledge, attitude, and practice. Subjects were obtained from the sub district of Limo, in Depok, West Java, which was considered a high risk area for Avian influenza. The heads of household as the sample unit were chosen by multi-stage sampling.Results: Among 387 subjects, 29.5% of them was had good behavior toward Avian influenza. The final model revealed that gender and access to health information were two dominant factors for good behavior in preventing Avian influenza. Compared with men, women had 67% higher risk to have good behavior [adjusted relative risk (RRa = 1.67; 95% confidence interval (CI = 0.92-3.04; P = 0.092]. Compared to those with no access to health information, subjects with access to health information had 3.4 fold increase to good behavior (RRa = 3.40; 95% CI =  0.84-13.76; P = 0.087.Conclusion: Acces to health information concerning Avian influenza was more effective among women in promoting good behavior toward preventing Avian influenza. (Med J Indones 2011; 20:56-61Keywords: avian influenza, behavior, gender, health promotion

  15. Avian Influenza A (H7N9) Virus

    Science.gov (United States)

    ... this? Submit Button Past Newsletters Avian Influenza A (H7N9) Virus Language: English Español Recommend on Facebook ... Fourth Epidemic — China, September 2015–August 2016." H7N9 Outbreak Characterization H7N9 infections in people and poultry ...

  16. Indirect transmission of highly pathogenic avian influenza in chickens

    NARCIS (Netherlands)

    Spekreijse, D.

    2013-01-01

    Highly Pathogenic Avian Influenza (HPAI), also known bird flu, is a serious infectious disease of chickens causing high mortality in flocks and economic damage for farmers. The control strategy to control an outbreak of HPAI in the Netherlands will include culling of infected flocks and depopulation

  17. Histopathologic study of avian influenza H5N1 infection in humans%人感染高致病性禽流感病毒H5N1的病理学观察

    Institute of Scientific and Technical Information of China (English)

    陆敏; 谢志刚; 高占成; 王辰; 李宁; 李敏; 邵宏权; 王玉萍; 高子芬

    2008-01-01

    目的 观察人感染高致病性禽流感病毒H5N1后各主要脏器的病理改变.方法 按传染病尸体解剖要求对2例死亡病例系统解剖,并获得心、肝、脾、肺和肾等主要脏器,对1例重症患者行肺大泡切除术,组织常规HE和免疫组织化学染色,光学显微镜下观察.结果 2例肺组织主要呈弥漫性肺泡损伤改变.早期呈渗出性改变,肺泡上皮坏死脱落,肺泡腔内见大量均匀粉染渗出液伴广泛透明膜形成.中晚期主要呈增生性和纤维化性改变,肺泡上皮和支气管上皮增生,肺泡腔内渗出物和肺间质纤维化.1例在慢性支气管扩张症基础上伴弥漫性肺泡损伤和肺间质纤维化.免疫器官改变:全身淋巴组织萎缩伴活跃的噬血现象.其他脏器病变:1例心脏有间质性心肌炎;1例肾脏有急性肾小管坏死;1例有脑水肿伴脑实质内神经细胞嗜酸性变,轴突肿胀,粗细不均.脑室旁见灶状坏死.1例孕妇胎盘内多灶状滋养叶细胞坏死伴营养不良性钙化,有急性坏死性蜕膜炎.胚胎肺脏有肺水肿和肺炎改变.结论 人感染高致病性禽流感病毒H5N1后首先出现呼吸系统症状,广泛弥漫性肺泡损伤致低氧血症是病理学基础,患者最终因多器官功能衰竭致呼吸、循环衰竭死亡.%Objective To identify histopathologic changes of major organs and to correlate clinical symptoms in patients