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.

Avian Influenza A Viruses: Evolution and Zoonotic Infection.

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Kim, Se Mi; Kim, Young-Il; Pascua, Philippe Noriel Q; Choi, Young Ki

2016-08-01

Although efficient human-to-human transmission of avian influenza virus has yet to be seen, in the past two decades avian-to-human transmission of influenza A viruses has been reported. Influenza A/H5N1, in particular, has repeatedly caused human infections associated with high mortality, and since 1998 the virus has evolved into many clades of variants with significant antigenic diversity. In 2013, three (A/H7N9, A/H6N1, and A/H10N8) novel avian influenza viruses (AIVs) breached the animal-human host species barrier in Asia. In humans, roughly 35% of A/H7N9-infected patients succumbed to the zoonotic infection, and two of three A/H10N8 human infections were also lethal; however, neither of these viruses cause influenza-like symptoms in poultry. While most of these cases were associated with direct contact with infected poultry, some involved sustained human-to-human transmission. Thus, these events elicited concern regarding potential AIV pandemics. This article reviews the human incursions associated with AIV variants and the potential role of pigs as an intermediate host that may hasten AIV evolution. In addition, we discuss the known influenza A virus virulence and transmission factors and their evaluation in animal models. With the growing number of human AIV infections, constant vigilance for the emergence of novel viruses is of utmost importance. In addition, careful characterization and pathobiological assessment of these novel variants will help to identify strains of particular concern for future pandemics. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

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

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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.

Diagnosing avian influenza infection in vaccinated populations by systems for differentiating infected from vaccinated animals (DIVA).

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Capua, I; Cattoli, G

2007-01-01

Vaccination against avian influenza is recommended as a tool to support control measures in countries affected by avian influenza. Vaccination is known to increase the resistance of susceptible birds to infection and also to reduce shedding; however, it does not always prevent infection. Vaccinated infected flocks can therefore be a source of infection and thus be responsible for the perpetuation of infection. To avoid the spread of infection in a vaccinated population, immunization strategies must allow differentiation of infected from vaccinated animals (DIVA), combined with an appropriate monitoring system. Vaccinated exposed flocks must be identified and managed by restriction policies that include controlled marketing and stamping-out. Several vaccines and diagnostic tests to detect infection in vaccinated populations are available, the tests having various properties and characteristics. In order to achieve eradication, the most appropriate DIVA vaccination strategy must be identified and an appropriate monitoring programme be designed, taking into account risk factors, the epidemiological situation and the socioeconomic implications of the policy.

Pathobiology of avian influenza virus infection in minor gallinaceous species: a review.

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Bertran, Kateri; Dolz, Roser; Majó, Natàlia

2014-01-01

Susceptibility to avian influenza viruses (AIVs) can vary greatly among bird species. Chickens and turkeys are major avian species that, like ducks, have been extensively studied for avian influenza. To a lesser extent, minor avian species such as quail, partridges, and pheasants have also been investigated for avian influenza. Usually, such game fowl species are highly susceptible to highly pathogenic AIVs and may consistently spread both highly pathogenic AIVs and low-pathogenic AIVs. These findings, together with the fact that game birds are considered bridge species in the poultry-wildlife interface, highlight their interest from the transmission and biosecurity points of view. Here, the general pathobiological features of low-pathogenic AIV and highly pathogenic AIV infections in this group of avian species have been covered.

Evidence for subclinical avian influenza virus infections among rural Thai villagers.

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Khuntirat, Benjawan P; Yoon, In-Kyu; Blair, Patrick J; Krueger, Whitney S; Chittaganpitch, Malinee; Putnam, Shannon D; Supawat, Krongkaew; Gibbons, Robert V; Pattamadilok, Sirima; Sawanpanyalert, Pathom; Heil, Gary L; Friary, John A; Capuano, Ana W; Gray, Gregory C

2011-10-01

Regions of Thailand reported sporadic outbreaks of A/H5N1 highly pathogenic avian influenza (HPAI) among poultry between 2004 and 2008. Kamphaeng Phet Province, in north-central Thailand had over 50 HPAI poultry outbreaks in 2004 alone, and 1 confirmed and 2 likely other human HPAI infections between 2004 and 2006. In 2008, we enrolled a cohort of 800 rural Thai adults living in 8 sites within Kamphaeng Phet Province in a prospective study of zoonotic influenza transmission. We studied participants' sera with serologic assays against 16 avian, 2 swine, and 8 human influenza viruses. Among participants (mean age 49.6 years and 58% female) 65% reported lifetime poultry exposure of at least 30 consecutive minutes. Enrollees had elevated antibodies by microneutralization assay against 3 avian viruses: A/Hong Kong/1073/1999(H9N2), A/Thailand/676/2005(H5N1), and A/Thailand/384/2006(H5N1). Bivariate risk factor modeling demonstrated that male gender, lack of an indoor water source, and tobacco use were associated with elevated titers against avian H9N2 virus. Multivariate modeling suggested that increasing age, lack of an indoor water source, and chronic breathing problems were associated with infection with 1 or both HPAI H5N1 strains. Poultry exposure was not associated with positive serologic findings. These data suggest that people in rural central Thailand may have experienced subclinical avian influenza infections as a result of yet unidentified environmental exposures. Lack of an indoor water source may play a role in transmission.

Virus-neutralizing antibody response of mice to consecutive infection with human and avian influenza A viruses.

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Janulíková, J; Stropkovská, A; Bobišová, Z; Košík, I; Mucha, V; Kostolanský, F; Varečková, E

2015-06-01

In this work we simulated in a mouse model a naturally occurring situation of humans, who overcame an infection with epidemic strains of influenza A, and were subsequently exposed to avian influenza A viruses (IAV). The antibody response to avian IAV in mice previously infected with human IAV was analyzed. We used two avian IAV (A/Duck/Czechoslovakia/1956 (H4N6) and the attenuated virus rA/Viet Nam/1203-2004 (H5N1)) as well as two human IAV isolates (virus A/Mississippi/1/1985 (H3N2) of medium virulence and A/Puerto Rico/8/1934 (H1N1) of high virulence). Two repeated doses of IAV of H4 or of H5 virus elicited virus-specific neutralizing antibodies in mice. Exposure of animals previously infected with human IAV (of H3 or H1 subtype) to IAV of H4 subtype led to the production of antibodies neutralizing H4 virus in a level comparable with the level of antibodies against the human IAV used for primary infection. In contrast, no measurable levels of virus-neutralizing (VN) antibodies specific to H5 virus were detected in mice infected with H5 virus following a previous infection with human IAV. In both cases the secondary infection with avian IAV led to a significant increase of the titer of VN antibodies specific to the corresponding human virus used for primary infection. Moreover, cross-reactive HA2-specific antibodies were also induced by sequential infection. By virtue of these results we suggest that the differences in the ability of avian IAV to induce specific antibodies inhibiting virus replication after previous infection of mice with human viruses can have an impact on the interspecies transmission and spread of avian IAV in the human population.

Serological Evidence of Human Infection with Avian Influenza A H7virus in Egyptian Poultry Growers.

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Gomaa, Mokhtar R; Kandeil, Ahmed; Kayed, Ahmed S; Elabd, Mona A; Zaki, Shaimaa A; Abu Zeid, Dina; El Rifay, Amira S; Mousa, Adel A; Farag, Mohamed M; McKenzie, Pamela P; Webby, Richard J; Ali, Mohamed A; Kayali, Ghazi

2016-01-01

Avian influenza viruses circulate widely in birds, with occasional human infections. Poultry-exposed individuals are considered to be at high risk of infection with avian influenza viruses due to frequent exposure to poultry. Some avian H7 viruses have occasionally been found to infect humans. Seroprevalence of neutralizing antibodies against influenza A/H7N7 virus among poultry-exposed and unexposed individuals in Egypt were assessed during a three-years prospective cohort study. The seroprevalence of antibodies (titer, ≥80) among exposed individuals was 0%, 1.9%, and 2.1% annually while the seroprevalence among the control group remained 0% as measured by virus microneutralization assay. We then confirmed our results using western blot and immunofluorescence assays. Although human infection with H7 in Egypt has not been reported yet, our results suggested that Egyptian poultry growers are exposed to avian H7 viruses. These findings highlight the need for surveillance in the people exposed to poultry to monitor the risk of zoonotic transmission of avian influenza viruses.

Serological Evidence of Human Infection with Avian Influenza A H7virus in Egyptian Poultry Growers.

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Mokhtar R Gomaa

Full Text Available Avian influenza viruses circulate widely in birds, with occasional human infections. Poultry-exposed individuals are considered to be at high risk of infection with avian influenza viruses due to frequent exposure to poultry. Some avian H7 viruses have occasionally been found to infect humans. Seroprevalence of neutralizing antibodies against influenza A/H7N7 virus among poultry-exposed and unexposed individuals in Egypt were assessed during a three-years prospective cohort study. The seroprevalence of antibodies (titer, ≥80 among exposed individuals was 0%, 1.9%, and 2.1% annually while the seroprevalence among the control group remained 0% as measured by virus microneutralization assay. We then confirmed our results using western blot and immunofluorescence assays. Although human infection with H7 in Egypt has not been reported yet, our results suggested that Egyptian poultry growers are exposed to avian H7 viruses. These findings highlight the need for surveillance in the people exposed to poultry to monitor the risk of zoonotic transmission of avian influenza viruses.

Differential lung NK cell responses in avian influenza virus infected chickens correlate with pathogenicity

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Jansen, C.A.; de Geus, E.D.; van Haarlem, D.A.; van de Haar, P.M.; Löndt, B.Z; Graham, S.P.; Göbel, T.W.; van Eden, W.; Brookes, S.M.; Vervelde, L.

2013-01-01

Infection of chickens with low pathogenicity avian influenza (LPAI) virus results in mild clinical signs while infection with highly pathogenic avian influenza (HPAI) viruses causes death of the birds within 36–48 hours. Since natural killer (NK) cells have been shown to play an important role in influenza-specific immunity, we hypothesise that NK cells are involved in this difference in pathogenicity. To investigate this, the role of chicken NK-cells in LPAI virus infection was studied. Next...

Evidence for avian H9N2 influenza virus infections among rural villagers in Cambodia

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Patrick J. Blair

2013-04-01

Full Text Available Summary: Background: Southeast Asia remains a critical region for the emergence of novel and/or zoonotic influenza, underscoring the importance of extensive sampling in rural areas where early transmission is most likely to occur. Methods: In 2008, 800 adult participants from eight sites were enrolled in a prospective population-based study of avian influenza (AI virus transmission where highly pathogenic avian influenza (HPAI H5N1 virus had been reported in humans and poultry from 2006 to 2008. From their enrollment sera and questionnaires, we report risk factor findings for serologic evidence of previous infection with 18 AI virus strains. Results: Serologic assays revealed no evidence of previous infection with 13 different low-pathogenic AI viruses or with HPAI avian-like A/Cambodia/R0404050/2007(H5N1. However, 21 participants had elevated antibodies against avian-like A/Hong Kong/1073/1999(H9N2, validated with a monoclonal antibody blocking ELISA assay specific for avian H9. Conclusions: Although cross-reaction from antibodies against human influenza viruses cannot be completely excluded, the study data suggest that a number of participants were previously infected with the avian-like A/Hong Kong/1073/1999(H9N2 virus, likely due to as yet unidentified environmental exposures. Prospective data from this cohort will help us better understand the serology of zoonotic influenza infection in a rural cohort in SE Asia. Keywords: Influenza A virus, Avian, Zoonoses, Occupational exposure, Communicable diseases, Emerging, Cohort studies

Evidence for avian H9N2 influenza virus infections among rural villagers in Cambodia.

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Blair, Patrick J; Putnam, Shannon D; Krueger, Whitney S; Chum, Channimol; Wierzba, Thomas F; Heil, Gary L; Yasuda, Chadwick Y; Williams, Maya; Kasper, Matthew R; Friary, John A; Capuano, Ana W; Saphonn, Vonthanak; Peiris, Malik; Shao, Hongxia; Perez, Daniel R; Gray, Gregory C

2013-04-01

Southeast Asia remains a critical region for the emergence of novel and/or zoonotic influenza, underscoring the importance of extensive sampling in rural areas where early transmission is most likely to occur. In 2008, 800 adult participants from eight sites were enrolled in a prospective population-based study of avian influenza (AI) virus transmission where highly pathogenic avian influenza (HPAI) H5N1 virus had been reported in humans and poultry from 2006 to 2008. From their enrollment sera and questionnaires, we report risk factor findings for serologic evidence of previous infection with 18 AI virus strains. Serologic assays revealed no evidence of previous infection with 13 different low-pathogenic AI viruses or with HPAI avian-like A/Cambodia/R0404050/2007(H5N1). However, 21 participants had elevated antibodies against avian-like A/Hong Kong/1073/1999(H9N2), validated with a monoclonal antibody blocking ELISA assay specific for avian H9. Although cross-reaction from antibodies against human influenza viruses cannot be completely excluded, the study data suggest that a number of participants were previously infected with the avian-like A/Hong Kong/1073/1999(H9N2) virus, likely due to as yet unidentified environmental exposures. Prospective data from this cohort will help us better understand the serology of zoonotic influenza infection in a rural cohort in SE Asia. Copyright © 2013 King Saud Bin Abdulaziz University for Health Sciences. All rights reserved.

Highly pathogenic avian influenza virus (H5N1) in experimentally infected adult mute swans.

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Kalthoff, Donata; Breithaupt, Angele; Teifke, Jens P; Globig, Anja; Harder, Timm; Mettenleiter, Thomas C; Beer, Martin

2008-08-01

Adult, healthy mute swans were experimentally infected with highly pathogenic avian influenza virus A/Cygnus cygnus/Germany/R65/2006 subtype H5N1. Immunologically naive birds died, whereas animals with preexisting, naturally acquired avian influenza virus-specific antibodies became infected asymptomatically and shed virus. Adult mute swans are highly susceptible, excrete virus, and can be clinically protected by preexposure immunity.

Expression patterns of endogenous avian retrovirus ALVE1 and its response to infection with exogenous avian tumour viruses.

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Hu, Xuming; Zhu, Wenqi; Chen, Shihao; Liu, Yangyang; Sun, Zhen; Geng, Tuoyu; Song, Chengyi; Gao, Bo; Wang, Xiaoyan; Qin, Aijian; Cui, Hengmi

2017-01-01

Endogenous retroviruses (ERVs) are genomic elements that are present in a wide range of vertebrates and have been implicated in a variety of human diseases, including cancer. However, the characteristic expression patterns of ERVs, particularly in virus-induced tumours, is not fully clear. DNA methylation was analysed by bisulfite pyrosequencing, and gene expression was analysed by RT-qPCR. In this study, we first found that the endogenous avian retrovirus ALVE1 was highly expressed in some chicken tissues (including the heart, bursa, thymus, and spleen) at 2 days of age, but its expression was markedly decreased at 35 days of age. In contrast, the CpG methylation level of ALVE1 was significantly lower in heart and bursa at 2 days than at 35 days of age. Moreover, we found that the expression of ALVE1 was significantly inhibited in chicken embryo fibroblast cells (CEFs) and MSB1 cells infected with avian leukosis virus subgroup J (ALVJ) and reticuloendotheliosis virus (REV) at the early stages of infection. In contrast, the expression of the ALVE1 env gene was significantly induced in CEFs and MSB1 cells infected with Marek's disease virus (MDV). However, the methylation and expression levels of the ALVE1 long terminal repeat (LTR) did not show obvious alterations in response to viral infection. The present study revealed the expression patterns of ALVE1 in a variety of chicken organs and tissues and in chicken cells in response to avian tumour virus infection. These findings may be of significance for understanding the role and function of ERVs that are present in the host genome.

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

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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...

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

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Whitney S Krueger

Full Text Available 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.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.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.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 accurately detect subclinical AIV infections in

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

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Krueger, Whitney S; Khuntirat, Benjawan; Yoon, In-Kyu; Blair, Patrick J; Chittagarnpitch, Malinee; Putnam, Shannon D; Supawat, Krongkaew; Gibbons, Robert V; Bhuddari, Darunee; Pattamadilok, Sirima; Sawanpanyalert, Pathom; Heil, Gary L; Gray, Gregory C

2013-01-01

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. 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. 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. 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 accurately detect subclinical AIV infections in humans.

Serological evidence for avian H9N2 influenza virus infections among Romanian agriculture workers.

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Coman, Alexandru; Maftei, Daniel N; Krueger, Whitney S; Heil, Gary L; Friary, John A; Chereches, Razvan M; Sirlincan, Emanuela; Bria, Paul; Dragnea, Claudiu; Kasler, Iosif; Gray, Gregory C

2013-12-01

In recent years, wild birds have introduced multiple highly pathogenic avian influenza (HPAI) H5N1 virus infections in Romanian poultry. In 2005 HPAI infections were widespread among domestic poultry and anecdotal reports suggested domestic pigs may also have been exposed. We sought to examine evidence for zoonotic influenza infections among Romanian agriculture workers. Between 2009 and 2010, 363 adult participants were enrolled in a cross-sectional, seroepidemiological study. Confined animal feeding operation (CAFO) swine workers in Tulcea and small, traditional backyard farmers in Cluj-Napoca were enrolled, as well as a non-animal exposed control group from Cluj-Napoca. Enrollment sera were examined for serological evidence of previous infection with 9 avian and 3 human influenza virus strains. Serologic assays showed no evidence of previous infection with 7 low pathogenic avian influenza viruses or with HPAI H5N1. However, 33 participants (9.1%) had elevated microneutralization antibody titers against avian-like A/Hong Kong/1073/1999(H9N2), 5 with titers ≥ 1:80 whom all reported exposure to poultry. Moderate poultry exposure was significantly associated with elevated titers after controlling for the subjects' age (adjusted OR = 3.6; 95% CI, 1.1-12.1). There was no evidence that previous infection with human H3N2 or H2N2 viruses were confounding the H9N2 seroreactivity. These data suggest that H9N2 virus may have circulated in Romanian poultry and occasionally infected man. Copyright © 2013 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

Sparse evidence for equine or avian influenza virus infections among Mongolian adults with animal exposures

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Khurelbaatar, Nyamdavaa; Krueger, Whitney S.; Heil, Gary L.; Darmaa, Badarchiin; Ulziimaa, Daramragchaa; Tserennorov, Damdindorj; Baterdene, Ariungerel; Anderson, Benjamin D.; Gray, Gregory C.

2013-01-01

In recent years, Mongolia has experienced recurrent epizootics of equine influenza virus (EIV) among its 2?1 million horses and multiple incursions of highly pathogenic avian influenza (HPAI) virus via migrating birds. No human EIV or HPAI infections have been reported. In 2009, 439 adults in Mongolia were enrolled in a population?based study of zoonotic influenza transmission. Enrollment sera were examined for serological evidence of infection with nine avian, three human, and one equine inf...

The onset of virus shedding and clinical signs in chickens infected with high-pathogenicity and low-pathogenicity avian influenza viruses.

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Spickler, Anna R; Trampel, Darrell W; Roth, James A

2008-12-01

Some avian influenza viruses may be transmissible to mammals by ingestion. Cats and dogs have been infected by H5N1 avian influenza viruses when they ate raw poultry, and two human H5N1 infections were linked to the ingestion of uncooked duck blood. The possibility of zoonotic influenza from exposure to raw poultry products raises concerns about flocks with unrecognized infections. The present review examines the onset of virus shedding and the development of clinical signs for a variety of avian influenza viruses in chickens. In experimentally infected birds, some high-pathogenicity avian influenza (HPAI) and low-pathogenicity avian influenza (LPAI) viruses can occur in faeces and respiratory secretions as early as 1 to 2 days after inoculation. Some HPAI viruses have also been found in meat 1 day after inoculation and in eggs after 3 days. There is no evidence that LPAI viruses can be found in meat, and the risk of their occurrence in eggs is poorly understood. Studies in experimentally infected birds suggest that clinical signs usually develop within a few days of virus shedding; however, some models and outbreak descriptions suggest that clinical signs may not become evident for a week or more in some H5 or H7 HPAI-infected flocks. During this time, avian influenza viruses might be found in poultry products. LPAI viruses can be shed in asymptomatically infected or minimally affected flocks, but these viruses are unlikely to cause significant human disease.

Sparse evidence for equine or avian influenza virus infections among Mongolian adults with animal exposures.

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Khurelbaatar, Nyamdavaa; Krueger, Whitney S; Heil, Gary L; Darmaa, Badarchiin; Ulziimaa, Daramragchaa; Tserennorov, Damdindorj; Baterdene, Ariungerel; Anderson, Benjamin D; Gray, Gregory C

2013-11-01

In recent years, Mongolia has experienced recurrent epizootics of equine influenza virus (EIV) among its 2·1 million horses and multiple incursions of highly pathogenic avian influenza (HPAI) virus via migrating birds. No human EIV or HPAI infections have been reported. In 2009, 439 adults in Mongolia were enrolled in a population-based study of zoonotic influenza transmission. Enrollment sera were examined for serological evidence of infection with nine avian, three human, and one equine influenza virus strains. Seroreactivity was sparse among participants suggesting little human risk of zoonotic influenza infection. © 2013 John Wiley & Sons Ltd.

Evidence of infection with avian, human, and swine influenza viruses in pigs in Cairo, Egypt.

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Gomaa, Mokhtar R; Kandeil, Ahmed; El-Shesheny, Rabeh; Shehata, Mahmoud M; McKenzie, Pamela P; Webby, Richard J; Ali, Mohamed A; Kayali, Ghazi

2018-02-01

The majority of the Egyptian swine population was culled in the aftermath of the 2009 H1N1 pandemic, but small-scale growing remains. We sampled pigs from piggeries and an abattoir in Cairo. We found virological evidence of infection with avian H9N2 and H5N1 viruses as well as human pandemic H1N1 influenza virus. Serological evidence suggested previous exposure to avian H5N1 and H9N2, human pandemic H1N1, and swine avian-like and human-like viruses. This raises concern about potential reassortment of influenza viruses in pigs and highlights the need for better control and prevention of influenza virus infection in pigs.

Avian Metapneumoviruses

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Avian metapneumovirus (aMPV) is an economically important virus that is the primary causal agent of turkey rhinotracheitis (TRT), also known as avian rhinotracheitis (ART). The virus causes an acute highly contagious infection of the upper respiratory tract in turkeys and was first isolated from tur...

Highly (H5N1 and low (H7N2 pathogenic avian influenza virus infection in falcons via nasochoanal route and ingestion of experimentally infected prey.

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Kateri Bertran

Full Text Available An experimental infection with highly pathogenic avian influenza (HPAI and low pathogenic avian influenza (LPAI viruses was carried out on falcons in order to examine the effects of these viruses in terms of pathogenesis, viral distribution in tissues and viral shedding. The distribution pattern of influenza virus receptors was also assessed. Captive-reared gyr-saker (Falco rusticolus x Falco cherrug hybrid falcons were challenged with a HPAI H5N1 virus (A/Great crested grebe/Basque Country/06.03249/2006 or a LPAI H7N2 virus (A/Anas plathyrhynchos/Spain/1877/2009, both via the nasochoanal route and by ingestion of previously infected specific pathogen free chicks. Infected falcons exhibited similar infection dynamics despite the different routes of exposure, demonstrating the effectiveness of in vivo feeding route. H5N1 infected falcons died, or were euthanized, between 5-7 days post-infection (dpi after showing acute severe neurological signs. Presence of viral antigen in several tissues was confirmed by immunohistochemistry and real time RT-PCR (RRT-PCR, which were generally associated with significant microscopical lesions, mostly in the brain. Neither clinical signs, nor histopathological findings were observed in any of the H7N2 LPAI infected falcons, although all of them had seroconverted by 11 dpi. Avian receptors were strongly present in the upper respiratory tract of the falcons, in accordance with the consistent oral viral shedding detected by RRT-PCR in both H5N1 HPAI and H7N2 LPAI infected falcons. The present study demonstrates that gyr-saker hybrid falcons are highly susceptible to H5N1 HPAI virus infection, as previously observed, and that they may play a major role in the spreading of both HPAI and LPAI viruses. For the first time in raptors, natural infection by feeding on infected prey was successfully reproduced. The use of avian prey species in falconry husbandry and wildlife rehabilitation facilities could put valuable birds

Highly (H5N1) and low (H7N2) pathogenic avian influenza virus infection in falcons via nasochoanal route and ingestion of experimentally infected prey.

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Bertran, Kateri; Busquets, Núria; Abad, Francesc Xavier; García de la Fuente, Jorge; Solanes, David; Cordón, Iván; Costa, Taiana; Dolz, Roser; Majó, Natàlia

2012-01-01

An experimental infection with highly pathogenic avian influenza (HPAI) and low pathogenic avian influenza (LPAI) viruses was carried out on falcons in order to examine the effects of these viruses in terms of pathogenesis, viral distribution in tissues and viral shedding. The distribution pattern of influenza virus receptors was also assessed. Captive-reared gyr-saker (Falco rusticolus x Falco cherrug) hybrid falcons were challenged with a HPAI H5N1 virus (A/Great crested grebe/Basque Country/06.03249/2006) or a LPAI H7N2 virus (A/Anas plathyrhynchos/Spain/1877/2009), both via the nasochoanal route and by ingestion of previously infected specific pathogen free chicks. Infected falcons exhibited similar infection dynamics despite the different routes of exposure, demonstrating the effectiveness of in vivo feeding route. H5N1 infected falcons died, or were euthanized, between 5-7 days post-infection (dpi) after showing acute severe neurological signs. Presence of viral antigen in several tissues was confirmed by immunohistochemistry and real time RT-PCR (RRT-PCR), which were generally associated with significant microscopical lesions, mostly in the brain. Neither clinical signs, nor histopathological findings were observed in any of the H7N2 LPAI infected falcons, although all of them had seroconverted by 11 dpi. Avian receptors were strongly present in the upper respiratory tract of the falcons, in accordance with the consistent oral viral shedding detected by RRT-PCR in both H5N1 HPAI and H7N2 LPAI infected falcons. The present study demonstrates that gyr-saker hybrid falcons are highly susceptible to H5N1 HPAI virus infection, as previously observed, and that they may play a major role in the spreading of both HPAI and LPAI viruses. For the first time in raptors, natural infection by feeding on infected prey was successfully reproduced. The use of avian prey species in falconry husbandry and wildlife rehabilitation facilities could put valuable birds of prey and

Pathobiology of highly pathogenic avian influenza virus (H5N1) infection in mute swans (Cygnus olor).

Science.gov (United States)

Pálmai, Nimród; Erdélyi, Károly; Bálint, Adám; Márton, Lázár; Dán, Adám; Deim, Zoltán; Ursu, Krisztina; Löndt, Brandon Z; Brown, Ian H; Glávits, Róbert

2007-06-01

The results of pathological, virological and polymerase chain reaction examinations carried out on 35 mute swans (Cygnus olor) that succumbed to a highly pathogenic avian influenza virus (H5N1) infection during an outbreak in Southern Hungary are reported. The most frequently observed macroscopic lesions included: haemorrhages under the epicardium, in the proventricular and duodenal mucosa and pancreas; focal necrosis in the pancreas; myocardial degeneration; acute mucous enteritis; congestion of the spleen and lung, and the accumulation of sero-mucinous exudate in the body cavity. Histopathological lesions comprised: lymphocytic meningo-encephalomyelitis accompanied by gliosis and occasional perivascular haemorrhages; multi-focal myocardial necrosis with lympho-histiocytic infiltration; pancreatitis with focal necrosis; acute desquamative mucous enteritis; lung congestion and oedema; oedema of the tracheal mucosa and, in young birds, the atrophy of the bursa of Fabricius as a result of lymphocyte depletion and apoptosis. The observed lesions and the moderate to good body conditions were compatible with findings in acute highly pathogenic avian influenza infections of other bird species reported in the literature. Skin lesions and lesions typical for infections caused by strains of lower pathogenicity (low pathogenic avian influenza virus) such as emaciation or fibrinous changes in the reproductive and respiratory organs, sinuses and airsacs were not observed. The H5N1 subtype avian influenza virus was isolated in embryonated fowl eggs from all cases and it was identified by classical and molecular virological methods.

Infectivity, transmission and pathogenicity of avian influenza viruses for domestic and wild birds

Science.gov (United States)

Individual avian influenza (AI) virus strains vary in their ability to infect, transmit and cause disease and death in different bird species. Low pathogenicity AI (LPAI) viruses are maintained in wild birds, and must be adapted to pass to domestic poultry, where they replicate in respiratory and in...

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

OpenAIRE

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

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...

Precision-cut intestinal slices as a culture system to analyze the infection of differentiated intestinal epithelial cells by avian influenza viruses.

Science.gov (United States)

Punyadarsaniya, Darsaniya; Winter, Christine; Mork, Ann-Kathrin; Amiri, Mahdi; Naim, Hassan Y; Rautenschlein, Silke; Herrler, Georg

2015-02-01

Many viruses infect and replicate in their host via the intestinal tract, e.g. many picornaviruses, several coronaviruses and avian influenza viruses of waterfowl. To analyze infection of enterocytes is a challenging task as culture systems for differentiated intestinal epithelial cells are not readily available and often have a life span that is too short for infection studies. Precision-cut intestinal slices (PCIS) from chicken embryos were prepared and shown that the epithelial cells lining the lumen of the intestine are viable for up to 4 days. Using lectin staining, it was demonstrated that α2,3-linked sialic acids, the preferred receptor determinants of avian influenza viruses, are present on the apical side of the epithelial cells. Furthermore, the epithelial cells (at the tips) of the villi were shown to be susceptible to infection by an avian influenza virus of the H9N2 subtype. This culture system will be useful to analyze virus infection of intestinal epithelial cells and it should be applicable also to the intestine of other species. Copyright © 2014 Elsevier B.V. All rights reserved.

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.

Bird Flu (Avian Influenza)

Science.gov (United States)

Bird flu (avian influenza) Overview Bird flu is caused by a type of influenza virus that rarely infects humans. More than a ... for Disease Control and Prevention estimates that seasonal influenza is responsible for ... heat destroys avian viruses, cooked poultry isn't a health threat. ...

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

NARCIS (Netherlands)

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.

2013-01-01

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

Preliminary Epidemiology of Human Infections with Highly Pathogenic Avian Influenza A(H7N9) Virus, China, 2017.

Science.gov (United States)

Zhou, Lei; Tan, Yi; Kang, Min; Liu, Fuqiang; Ren, Ruiqi; Wang, Yali; Chen, Tao; Yang, Yiping; Li, Chao; Wu, Jie; Zhang, Hengjiao; Li, Dan; Greene, Carolyn M; Zhou, Suizan; Iuliano, A Danielle; Havers, Fiona; Ni, Daxin; Wang, Dayan; Feng, Zijian; Uyeki, Timothy M; Li, Qun

2017-08-01

We compared the characteristics of cases of highly pathogenic avian influenza (HPAI) and low pathogenic avian influenza (LPAI) A(H7N9) virus infections in China. HPAI A(H7N9) case-patients were more likely to have had exposure to sick and dead poultry in rural areas and were hospitalized earlier than were LPAI A(H7N9) case-patients.

Avian Flu

International Nuclear Information System (INIS)

Eckburg, Paul

2006-01-01

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.

Baicalin is an inhibitor of subgroup J avian leukosis virus infection.

Science.gov (United States)

Qian, Kun; Kong, Zheng-Ru; Zhang, Jie; Cheng, Xiao-Wei; Wu, Zong-Yi; Gu, Cheng-Xi; Shao, Hong-Xia; Qin, Ai-Jian

2018-03-15

Avian leukosis virus subgroup J (ALV-J) can cause great economic losses to the poultry industry worldwide. Baicalin, one of the flavonoids present in S.baicalensis Georgi, has been shown to have antiviral activities. To investigate whether baicalin has antiviral effects on the infection of ALV-J in DF-1 cells, the cells were treated with baicalin at different time points. We found that baicalin could inhibit viral mRNA, protein levels and overall virus infection in a dose- and time-dependent manner using a variety of assays. Baicalin specifically targeted virus internalization and reduced the infectivity of ALV-J particles, but had no effect on the levels of major ALV-J receptor and virus binding to DF-1 cells. Collectively, these results suggest that baicalin might have potential to be developed as a novel antiviral agent for ALV-J infection. Copyright © 2018 Elsevier B.V. All rights reserved.

Effects of Cyclosporin A induced T-lymphocyte depletion on the course of avian Metapneumovirus (aMPV) infection in turkeys

DEFF Research Database (Denmark)

Rubbenstroth, Dennis; Dalgaard, Tina S; Kothlow, Sonja

2010-01-01

The avian Metapneumovirus (aMPV) causes an economically important acute respiratory disease in turkeys (turkey rhinotracheitis, TRT).While antibodies were shownto be insufficient for protection against a MPV-infection, the role of T-lymphocytes in the control of aMPV-infection is not clear...... to untreated controls (P infection...

Experimental infection of highly pathogenic avian influenza virus H5N1 in black-headed gulls (Chroicocephalus ridibundus)

NARCIS (Netherlands)

A. Ramis (Antonio); G. van Amerongen (Geert); M.W.G. van de Bildt (Marco); L.M.E. Leijten (Lonneke); R. Vanderstichel (R.); A.D.M.E. Osterhaus (Albert); T. Kuiken (Thijs)

2014-01-01

textabstractHistorically, highly pathogenic avian influenza viruses (HPAIV) rarely resulted in infection or clinical disease in wild birds. However, since 2002, disease and mortality from natural HPAIV H5N1 infection have been observed in wild birds including gulls. We performed an experimental

Efficacy of gamithromycin against Ornithobacterium rhinotracheale in turkey poults pre-infected with avian metapneumovirus.

Science.gov (United States)

Watteyn, Anneleen; Devreese, Mathias; Plessers, Elke; Wyns, Heidi; Garmyn, An; Reddy, Vishwanatha R A P; Pasmans, Frank; Martel, An; Haesebrouck, Freddy; De Backer, Patrick; Croubels, Siska

2016-10-01

Ornithobacterium rhinotracheale is an avian respiratory pathogen that affects turkeys. The objective of this study was to evaluate the clinical efficacy of gamithromycin (GAM) against O. rhinotracheale in turkeys. The birds were inoculated oculonasally with 10(8) colony-forming units (cfu) of O. rhinotracheale, preceded by infection with avian metapneumovirus. In addition to a negative (CONTR-) and a positive control group (CONTR+) there were two treated groups administered GAM (6 mg/kg) either subcutaneously (GAM SC) or orally (GAM PO) by administration as a single bolus at one-day post-bacterial infection (p.b.i.). From the start of the avian metapneumovirus infection until the end of the experiment, the turkeys were examined clinically and scored daily. In addition, tracheal swabs were collected at several days p.b.i. Necropsy was performed at 4, 8 and 12 days p.b.i. to evaluate the presence of gross lesions, and to collect trachea and lung tissue samples and air sac swabs for O. rhinotracheale quantification. The clinical score of the GAM SC group showed slightly lower values and birds recovered earlier than those in the GAM PO and CONTR+ groups. O. rhinotracheale cfus were significantly reduced in tracheal swabs of the SC group between 2 and 4 days p.b.i. At necropsy, CONTR+ showed higher O. rhinotracheale cfu in lung tissues compared to the treated groups. Moreover, at 8 days p.b.i. only the lung samples of CONTR+ were positive. In conclusion, the efficacy of GAM against O. rhinotracheale was demonstrated, especially in the lung tissue. However, the PO bolus administration of the commercially available product was not as efficacious as the SC bolus.

Little evidence of avian or equine influenza virus infection among a cohort of Mongolian adults with animal exposures, 2010-2011.

Science.gov (United States)

Khurelbaatar, Nyamdavaa; Krueger, Whitney S; Heil, Gary L; Darmaa, Badarchiin; Ulziimaa, Daramragchaa; Tserennorov, Damdindorj; Baterdene, Ariungerel; Anderson, Benjamin D; Gray, Gregory C

2014-01-01

Avian (AIV) and equine influenza virus (EIV) have been repeatedly shown to circulate among Mongolia's migrating birds or domestic horses. In 2009, 439 Mongolian adults, many with occupational exposure to animals, were enrolled in a prospective cohort study of zoonotic influenza transmission. Sera were drawn upon enrollment and again at 12 and 24 months. Participants were contacted monthly for 24 months and queried regarding episodes of acute influenza-like illnesses (ILI). Cohort members confirmed to have acute influenza A infections, permitted respiratory swab collections which were studied with rRT-PCR for influenza A. Serologic assays were performed against equine, avian, and human influenza viruses. Over the 2 yrs of follow-up, 100 ILI investigations in the cohort were conducted. Thirty-six ILI cases (36%) were identified as influenza A infections by rRT-PCR; none yielded evidence for AIV or EIV. Serological examination of 12 mo and 24 mo annual sera revealed 37 participants had detectable antibody titers (≥1∶10) against studied viruses during the course of study follow-up: 21 against A/Equine/Mongolia/01/2008(H3N8); 4 against an avian A/Teal/Hong Kong/w3129(H6N1), 11 against an avian-like A/Hong Kong/1073/1999(H9N2), and 1 against an avian A/Migrating duck/Hong Kong/MPD268/2007(H10N4) virus. However, all such titers were avian or horse exposures. A number of subjects had evidence of seroconversion to zoonotic viruses, but the 4-fold titer changes were again not associated with avian or horse exposures. As elevated antibodies against seasonal influenza viruses were high during the study period, it seems likely that cross-reacting antibodies against seasonal human influenza viruses were a cause of the low-level seroreactivity against AIV or EIV. Despite the presence of AIV and EIV circulating among wild birds and horses in Mongolia, there was little evidence of AIV or EIV infection in this prospective study of Mongolians with animal exposures.

Avian Influenza (H7N9) Virus Infection in Chinese Tourist in Malaysia, 2014

OpenAIRE

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.

Fatal H5N6 Avian Influenza Virus Infection in a Domestic Cat and Wild Birds in China.

Science.gov (United States)

Yu, Zhijun; Gao, Xiaolong; Wang, Tiecheng; Li, Yanbing; Li, Yongcheng; Xu, Yu; Chu, Dong; Sun, Heting; Wu, Changjiang; Li, Shengnan; Wang, Haijun; Li, Yuanguo; Xia, Zhiping; Lin, Weishi; Qian, Jun; Chen, Hualan; Xia, Xianzhu; Gao, Yuwei

2015-06-02

H5N6 avian influenza viruses (AIVs) may pose a potential human risk as suggested by the first documented naturally-acquired human H5N6 virus infection in 2014. Here, we report the first cases of fatal H5N6 avian influenza virus (AIV) infection in a domestic cat and wild birds. These cases followed human H5N6 infections in China and preceded an H5N6 outbreak in chickens. The extensive migration routes of wild birds may contribute to the geographic spread of H5N6 AIVs and pose a risk to humans and susceptible domesticated animals, and the H5N6 AIVs may spread from southern China to northern China by wild birds. Additional surveillance is required to better understand the threat of zoonotic transmission of AIVs.

Avian influenza surveillance and diagnosis

Science.gov (United States)

Rapid detection and accurate identification of low (LPAI) and high pathogenicity avian influenza (HPAI) is critical to controlling infections and disease in poultry. Test selection and algorithms for the detection and diagnosis of avian influenza virus (AIV) in poultry may vary somewhat among differ...

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.

Avian influenza: a review.

Science.gov (United States)

Thomas, Jennifer K; Noppenberger, Jennifer

2007-01-15

A review of the avian influenza A/H5N1 virus, including human cases, viral transmission, clinical features, vaccines and antivirals, surveillance plans, infection control, and emergency response plans, is presented. The World Health Organization (WHO) considers the avian influenza A/H5N1 virus a public health risk with pandemic potential. The next human influenza pandemic, if caused by the avian influenza A/H5N1 virus, is estimated to have a potential mortality rate of more than a hundred million. Outbreaks in poultry have been associated with human transmission. WHO has documented 258 confirmed human infections with a mortality rate greater than 50%. Bird-to-human transmission of the avian influenza virus is likely by the oral-fecal route. The most effective defense against an influenza pandemic would be a directed vaccine to elicit a specific immune response toward the strain or strains of the influenza virus. However, until there is an influenza pandemic, there is no evidence that vaccines or antivirals used in the treatment or prevention of such an outbreak would decrease morbidity or mortality. Surveillance of the bird and human populations for the highly pathogenic H5N1 is being conducted. Infection-control measures and an emergency response plan are discussed. Avian influenza virus A/H5N1 is a public health threat that has the potential to cause serious illness and death in humans. Understanding its pathology, transmission, clinical features, and pharmacologic treatments and preparing for the prevention and management of its outbreak will help avoid its potentially devastating consequences.

Experimental infection of highly pathogenic avian influenza virus H5N1 in black-headed gulls (Chroicocephalus ridibundus)

OpenAIRE

Ramis , Antonio; van Amerongen , Geert; van de Bildt , Marco; Leijten , Loneke; Vanderstichel , Raphael; Osterhaus , Albert; Kuiken , Thijs

2014-01-01

Historically, highly pathogenic avian influenza viruses (HPAIV) rarely resulted in infection or clinical disease in wild birds. However, since 2002, disease and mortality from natural HPAIV H5N1 infection have been observed in wild birds including gulls. We performed an experimental HPAIV H5N1 infection of black-headed gulls (Chroicocephalus ridibundus) to determine their susceptibility to infection and disease from this virus, pattern of viral shedding, clinical signs, pathological changes a...

Little Evidence of Avian or Equine Influenza Virus Infection among a Cohort of Mongolian Adults with Animal Exposures, 2010–2011

Science.gov (United States)

Khurelbaatar, Nyamdavaa; Krueger, Whitney S.; Heil, Gary L.; Darmaa, Badarchiin; Ulziimaa, Daramragchaa; Tserennorov, Damdindorj; Baterdene, Ariungerel; Anderson, Benjamin D.; Gray, Gregory C.

2014-01-01

Avian (AIV) and equine influenza virus (EIV) have been repeatedly shown to circulate among Mongolia’s migrating birds or domestic horses. In 2009, 439 Mongolian adults, many with occupational exposure to animals, were enrolled in a prospective cohort study of zoonotic influenza transmission. Sera were drawn upon enrollment and again at 12 and 24 months. Participants were contacted monthly for 24 months and queried regarding episodes of acute influenza-like illnesses (ILI). Cohort members confirmed to have acute influenza A infections, permitted respiratory swab collections which were studied with rRT-PCR for influenza A. Serologic assays were performed against equine, avian, and human influenza viruses. Over the 2 yrs of follow-up, 100 ILI investigations in the cohort were conducted. Thirty-six ILI cases (36%) were identified as influenza A infections by rRT-PCR; none yielded evidence for AIV or EIV. Serological examination of 12 mo and 24 mo annual sera revealed 37 participants had detectable antibody titers (≥1∶10) against studied viruses during the course of study follow-up: 21 against A/Equine/Mongolia/01/2008(H3N8); 4 against an avian A/Teal/Hong Kong/w3129(H6N1), 11 against an avian-like A/Hong Kong/1073/1999(H9N2), and 1 against an avian A/Migrating duck/Hong Kong/MPD268/2007(H10N4) virus. However, all such titers were avian or horse exposures. A number of subjects had evidence of seroconversion to zoonotic viruses, but the 4-fold titer changes were again not associated with avian or horse exposures. As elevated antibodies against seasonal influenza viruses were high during the study period, it seems likely that cross-reacting antibodies against seasonal human influenza viruses were a cause of the low-level seroreactivity against AIV or EIV. Despite the presence of AIV and EIV circulating among wild birds and horses in Mongolia, there was little evidence of AIV or EIV infection in this prospective study of Mongolians with animal exposures. PMID

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.

The infection of chicken tracheal epithelial cells with a H6N1 avian influenza virus.

Directory of Open Access Journals (Sweden)

Ching-I Shen

Full Text Available Sialic acids (SAs linked to galactose (Gal in α2,3- and α2,6-configurations are the receptors for avian and human influenza viruses, respectively. We demonstrate that chicken tracheal ciliated cells express α2,3-linked SA, while goblet cells mainly express α2,6-linked SA. In addition, the plant lectin MAL-II, but not MAA/MAL-I, is bound to the surface of goblet cells, suggesting that SA2,3-linked oligosaccharides with Galβ1-3GalNAc subterminal residues are specifically present on the goblet cells. Moreover, both α2,3- and α2,6-linked SAs are detected on single tracheal basal cells. At a low multiplicity of infection (MOI avian influenza virus H6N1 is exclusively detected in the ciliated cells, suggesting that the ciliated cell is the major target cell of the H6N1 virus. At a MOI of 1, ciliated, goblet and basal cells are all permissive to the AIV infection. This result clearly elucidates the receptor distribution for the avian influenza virus among chicken tracheal epithelial cells and illustrates a primary cell model for evaluating the cell tropisms of respiratory viruses in poultry.

Avian influenza viruses in humans.

Science.gov (United States)

Malik Peiris, J S

2009-04-01

Past pandemics arose from low pathogenic avian influenza (LPAI) viruses. In more recent times, highly pathogenic avian influenza (HPAI) H5N1, LPAI H9N2 and both HPAI and LPAI H7 viruses have repeatedly caused zoonotic disease in humans. Such infections did not lead to sustained human-to-human transmission. Experimental infection of human volunteers and seroepidemiological studies suggest that avian influenza viruses of other subtypes may also infect humans. Viruses of the H7 subtype appear to have a predilection to cause conjunctivitis and influenza-like illness (ILI), although HPAI H7N7 virus has also caused fatal respiratory disease. Low pathogenic H9N2 viruses have caused mild ILI and its occurrence may be under-recognised for this reason. In contrast, contemporary HPAI H5N1 viruses are exceptional in their virulence for humans and differ from human seasonal influenza viruses in their pathogenesis. Patients have a primary viral pneumonia progressing to acute respiratory distress syndrome (ARDS) and multiple organ dysfunction syndrome. Over 380 human cases have been confirmed to date, with an overall case fatality of 63%. The zoonotic transmission of avian influenza is a rare occurrence, butthe greater public health concern is the adaptation of such viruses to efficient human transmission, which could lead to a pandemic. A better understanding of the ecology of avian influenza viruses and the biological determinants of transmissibility and pathogenicity in humans is important for pandemic preparedness.

Pathogenesis of avian pneumovirus infection in turkeys.

Science.gov (United States)

Jirjis, F F; Noll, S L; Halvorson, D A; Nagaraja, K V; Shaw, D P

2002-05-01

Avian pneumovirus (APV) is the cause of a respiratory disease of turkeys characterized by coughing, ocular and nasal discharge, and swelling of the infraorbital sinuses. Sixty turkey poults were reared in isolation conditions. At 3 weeks of age, serum samples were collected and determined to be free of antibodies against APV, avian influenza, hemorrhagic enteritis, Newcastle disease, Mycoplasma gallisepticum, Mycoplasma synoviae, Mycoplasma meleagridis, Ornithobacterium rhinotracheale, and Bordetella avium. When the poults were 4 weeks old, they were inoculated with cell culture-propagated APV (APV/Minnesota/turkey/2a/97) via the conjunctival spaces and nostrils. After inoculation, four poults were euthanatized every 2 days for 14 days, and blood, swabs, and tissues were collected. Clinical signs consisting of nasal discharge, swelling of the infraorbital sinuses, and frothy ocular discharge were evident by 2 days postinoculation (PI) and persisted until day 12 PI. Mild inflammation of the mucosa of the nasal turbinates and infraorbital sinuses was present between days 2 and 10 PI. Mild inflammatory changes were seen in tracheas of poults euthanatized between days 4 and 10 PI. Antibody to APV was detected by day 7 PI. The virus was detected in tissue preparations and swabs of nasal turbinates and infraorbital sinuses by reverse transcription polymerase chain reaction, virus isolation, and immunohistochemical staining methods between days 2 and 10 PI. Virus was detected in tracheal tissue and swabs between days 2 and 6 PI using the same methods. In this experiment, turkey poults inoculated with tissue culture-propagated APV developed clinical signs similar to those seen in field cases associated with infection with this virus.

Detection, prevalence, and transmission of avian hematozoa in waterfowl at the Arctic/sub-Arctic interface: co-infections, viral interactions, and sources of variation.

Science.gov (United States)

Meixell, Brandt; Arnold, Todd W.; Lindberg, Mark S.; Smith, Matthew M.; Runstadler, Jonathan A.; Ramey, Andy M.

2016-01-01

Background: The epidemiology of avian hematozoa at high latitudes is still not well understood, particularly in sub-Arctic and Arctic habitats, where information is limited regarding seasonality and range of transmission, co-infection dynamics with parasitic and viral agents, and possible fitness consequences of infection. Such information is important as climate warming may lead to northward expansion of hematozoa with unknown consequences to northern-breeding avian taxa, particularly populations that may be previously unexposed to blood parasites.

Little evidence of avian or equine influenza virus infection among a cohort of Mongolian adults with animal exposures, 2010-2011.

Directory of Open Access Journals (Sweden)

Nyamdavaa Khurelbaatar

Full Text Available Avian (AIV and equine influenza virus (EIV have been repeatedly shown to circulate among Mongolia's migrating birds or domestic horses. In 2009, 439 Mongolian adults, many with occupational exposure to animals, were enrolled in a prospective cohort study of zoonotic influenza transmission. Sera were drawn upon enrollment and again at 12 and 24 months. Participants were contacted monthly for 24 months and queried regarding episodes of acute influenza-like illnesses (ILI. Cohort members confirmed to have acute influenza A infections, permitted respiratory swab collections which were studied with rRT-PCR for influenza A. Serologic assays were performed against equine, avian, and human influenza viruses. Over the 2 yrs of follow-up, 100 ILI investigations in the cohort were conducted. Thirty-six ILI cases (36% were identified as influenza A infections by rRT-PCR; none yielded evidence for AIV or EIV. Serological examination of 12 mo and 24 mo annual sera revealed 37 participants had detectable antibody titers (≥1∶10 against studied viruses during the course of study follow-up: 21 against A/Equine/Mongolia/01/2008(H3N8; 4 against an avian A/Teal/Hong Kong/w3129(H6N1, 11 against an avian-like A/Hong Kong/1073/1999(H9N2, and 1 against an avian A/Migrating duck/Hong Kong/MPD268/2007(H10N4 virus. However, all such titers were <1∶80 and none were statistically associated with avian or horse exposures. A number of subjects had evidence of seroconversion to zoonotic viruses, but the 4-fold titer changes were again not associated with avian or horse exposures. As elevated antibodies against seasonal influenza viruses were high during the study period, it seems likely that cross-reacting antibodies against seasonal human influenza viruses were a cause of the low-level seroreactivity against AIV or EIV. Despite the presence of AIV and EIV circulating among wild birds and horses in Mongolia, there was little evidence of AIV or EIV infection in this

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.

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.

Unexpected infection outcomes of China-origin H7N9 low pathogenicity avian influenza virus in turkeys.

Science.gov (United States)

Slomka, Marek J; Seekings, Amanda H; Mahmood, Sahar; Thomas, Saumya; Puranik, Anita; Watson, Samantha; Byrne, Alexander M P; Hicks, Daniel; Nunez, Alejandro; Brown, Ian H; Brookes, Sharon M

2018-05-09

The China-origin H7N9 low pathogenicity avian influenza virus (LPAIV) emerged as a zoonotic threat in 2013 where it continues to circulate in live poultry markets. Absence of overt clinical signs in poultry is a typical LPAIV infection outcome, and has contributed to its insidious maintenance in China. This study is the first description of H7N9 LPAIV (A/Anhui/1/13) infection in turkeys, with efficient transmission to two additional rounds of introduced contact turkeys which all became infected during cohousing. Surprisingly, mortality was observed in six of eight (75%) second-round contact turkeys which is unusual for LPAIV infection, with unexpected systemic dissemination to many organs beyond the respiratory and enteric tracts, but interestingly no accompanying mutation to highly pathogenic AIV. The intravenous pathogenicity index score for a turkey-derived isolate (0.39) affirmed the LPAIV phenotype. However, the amino acid change L235Q in the haemagglutinin gene occurred in directly-infected turkeys and transmitted to the contacts, including those that died and the two which resolved infection to survive to the end of the study. This polymorphism was indicative of a reversion from mammalian to avian adaptation for the H7N9 virus. This study underlined a new risk to poultry in the event of H7N9 spread beyond China.

Avian pox

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Hansen, W.

1999-01-01

Avian pox is the common name for a mild-to-severe, slowdeveloping disease of birds that is caused by a large virus belonging to the avipoxvirus group, a subgroup of poxviruses. This group contains several similar virus strains; some strains have the ability to infect several groups or species of birds but others appear to be species-specific. Mosquitoes are common mechanical vectors or transmitters of this disease. Avian pox is transmitted when a mosquito feeds on an infected bird that has viremia or pox virus circulating in its blood, or when a mosquito feeds on virus-laden secretions seeping from a pox lesion and then feeds on another bird that is susceptible to that strain of virus. Contact with surfaces or exposure to air-borne particles contaminated with poxvirus can also result in infections when virus enters the body through abraded skin or the conjunctiva or the mucous membrane lining that covers the front part of the eyeball and inner surfaces of the eyelids of the eye.

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

Distribution of sialic acid receptors and influenza A virus of avian and swine origin in experimentally infected pigs

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Viuff Birgitte M

2011-09-01

Full Text Available Abstract 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 (SA-alpha-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 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 in bronchiolar epithelial cells. SA-alpha-2,6 was the predominant receptor in all areas of the respiratory tract with an average of 80-100% lining at the epithelial cells. On the contrary, the SA-alpha-2,3 was not present (0% at epithelial cells of nose, trachea, and most bronchi, but was found in small 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 and AIV virus was found, and this difference was in accordance with the distribution of the SA-alpha-2,6 and SA-alpha-2,3 receptor, respectively. The results indicated

High probability of avian influenza virus (H7N7) transmission from poultry to humans active in disease control on infected farms

NARCIS (Netherlands)

M.E.H. Bos (Marian); D.E. te Beest (Dennis); M. van Boven (Michiel); M.R.D.R.B. van Holle; A. Meijer (Adam); A. Bosman (Arnold); Y.M. Mulder (Yonne); M.P.G. Koopmans D.V.M. (Marion); A. Stegeman (Arjan)

2010-01-01

textabstractAn epizootic of avian influenza (H7N7) caused a large number of human infections in The Netherlands in 2003. We used data from this epizootic to estimate infection probabilities for persons involved in disease control on infected farms. Analyses were based on databases containing

Avian influenza in birds and mammals.

Science.gov (United States)

Cardona, Carol J; Xing, Zheng; Sandrock, Christian E; Davis, Cristina E

2009-07-01

The disease syndromes caused by avian influenza viruses are highly variable depending on the host species infected, its susceptibility and response to infection and the virulence of the infecting viral strain. Although avian influenza viruses have a broad host range in general, it is rare for an individual strain or subtype to infect more than one species. The H5N1 highly pathogenic avian influenza virus (HPAIV) lineages of viruses that descended from A/goose/Guandong/96 (H5N1 HPAIV) are unusual in the diversity of species they have infected worldwide. Although the species affected by H5N1 HPAI in the field and those that have been experimentally studied are diverse, their associated disease syndromes are remarkably similar across species. In some species, multi-organ failure and death are rapid and no signs of the disease are observed. Most prominently in this category are chickens and other avian species of the order Galliformes. In other species, neurologic signs develop resulting in the death of the host. This is what has been reported in domestic cats (Carnivora), geese (Anseriformes), ratites (Struthioniformes), pigeons inoculated with high doses (Columbiformes) and ducks infected with H5N1 HPAIV isolated since 2002 (Anseriformes). In some other species, the disease is more prolonged and although multi-organ failure and death are the eventual outcomes, the signs of disease are more extensive. Predominantly, these species include humans (Primates) and the laboratory models of human disease, the ferret (Carnivora), mouse (Rodentia) and cynamologous macaques (Primates). Finally, some species are more resistant to infection with H5N1 HPAIV and show few or no signs of disease. These species include pigeons in some studies (Columbiformes), ducks inoculated with pre-2002 isolates (Anseriformes), and pigs (Artiodactyla).

Disclosing respiratory co-infections: a broad-range panel assay for avian respiratory pathogens on a nanofluidic PCR platform.

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Croville, Guillaume; Foret, Charlotte; Heuillard, Pauline; Senet, Alexis; Delpont, Mattias; Mouahid, Mohammed; Ducatez, Mariette F; Kichou, Faouzi; Guerin, Jean-Luc

2018-06-01

Respiratory syndromes (RS) are among the most significant pathological conditions in edible birds and are caused by complex coactions of pathogens and environmental factors. In poultry, low pathogenic avian influenza A viruses, metapneumoviruses, infectious bronchitis virus, infectious laryngotracheitis virus, Mycoplasma spp. Escherichia coli and/or Ornithobacterium rhinotracheale in turkeys are considered as key co-infectious agents of RS. Aspergillus sp., Pasteurella multocida, Avibacterium paragallinarum or Chlamydia psittaci may also be involved in respiratory outbreaks. An innovative quantitative PCR method, based on a nanofluidic technology, has the ability to screen up to 96 samples with 96 pathogen-specific PCR primers, at the same time, in one run of real-time quantitative PCR. This platform was used for the screening of avian respiratory pathogens: 15 respiratory agents, including viruses, bacteria and fungi potentially associated with respiratory infections of poultry, were targeted. Primers were designed and validated for SYBR green real-time quantitative PCR and subsequently validated on the Biomark high throughput PCR nanofluidic platform (Fluidigm©, San Francisco, CA, USA). As a clinical assessment, tracheal swabs were sampled from turkeys showing RS and submitted to this panel assay. Beside systematic detection of E. coli, avian metapneumovirus, Mycoplasma gallisepticum and Mycoplasma synoviae were frequently detected, with distinctive co-infection patterns between French and Moroccan flocks. This proof-of-concept study illustrates the potential of such panel assays for unveiling respiratory co-infection profiles in poultry.

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.

Detecting emerging transmissibility of avian influenza virus in human households

NARCIS (Netherlands)

Boven, M. van; Koopmans, M.; Du Ry van Beest Holle, M.; Meijer, Adam; Klinkenberg, D.; Donnelly, C.A.; Heesterbeek, J.A.P.

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,

Detecting emerging transmissibility of avian influenza virus in human households

NARCIS (Netherlands)

Boven, van R.M.; Koopmans, M.; Du Ry Beest Holle, van M.; Meijer, A.; Klinkenberg, D.; Donnelly, C.; Heesterbeek, J.A.P.

2007-01-01

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,

The public health impact of avian influenza viruses.

Science.gov (United States)

Katz, J M; Veguilla, V; Belser, J A; Maines, T R; Van Hoeven, N; Pappas, C; Hancock, K; Tumpey, T M

2009-04-01

Influenza viruses with novel hemagglutinin and 1 or more accompanying genes derived from avian influenza viruses sporadically emerge in humans and have the potential to result in a pandemic if the virus causes disease and spreads efficiently in a population that lacks immunity to the novel hemagglutinin. Since 1997, multiple avian influenza virus subtypes have been transmitted directly from domestic poultry to humans and have caused a spectrum of human disease, from asymptomatic to severe and fatal. To assess the pandemic risk that avian influenza viruses pose, we have used multiple strategies to better understand the capacity of avian viruses to infect, cause disease, and transmit among mammals, including humans. Seroepidemiologic studies that evaluate the frequency and risk of human infection with avian influenza viruses in populations with exposure to domestic or wild birds can provide a better understanding of the pandemic potential of avian influenza subtypes. Investigations conducted in Hong Kong following the first H5N1 outbreak in humans in 1997 determined that exposure to poultry in live bird markets was a key risk factor for human disease. Among poultry workers, butchering and exposure to sick poultry were risk factors for antibody to H5 virus, which provided evidence for infection. A second risk assessment tool, the ferret, can be used to evaluate the level of virulence and potential for host-to-host transmission of avian influenza viruses in this naturally susceptible host. Avian viruses isolated from humans exhibit a level of virulence and transmissibility in ferrets that generally reflects that seen in humans. The ferret model thus provides a means to monitor emerging avian influenza viruses for pandemic risk, as well as to evaluate laboratory-generated reassortants and mutants to better understand the molecular basis of influenza virus transmissibility. Taken together, such studies provide valuable information with which we can assess the public

Low pathogenicity avian influenza viruses infect chicken layers by different routes of inoculation.

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Pantin-Jackwood, Mary J; Smith, Diane M; Wasilenko, Jamie L; Spackman, Erica

2012-06-01

In order to develop better control measures against avian influenza, it is necessary to understand how the virus transmits in poultry. In a previous study in which the infectivity and transmissibility of the pandemic H1N1 influenza virus was examined in different poultry species, we found that no or minimal infection occurred in chicken and turkeys intranasally (IN) inoculated with the virus. However, we demonstrated that the virus can infect laying turkey hens by the intracloacal (IC) and intraoviduct (IO) routes, possibly explaining the drops in egg production observed in turkey breeder farms affected by the virus. Such novel routes of exposure have not been previously examined in chickens and could also explain outbreaks of low pathogenicity avian influenza (LPAI) that cause a decrease in egg production in chicken layers and breeders. In the present study, 46-wk-old specific-pathogen-free chicken layers were infected by the IN, IC, or IO routes with one of two LPAI viruses: a poultry origin virus, A/chicken/CA/1255/02 (H6N2), and a live bird market isolate, A/chicken/NJ/12220/97 (H9N2). Only hens IN inoculated with the H6N2 virus presented mild clinical signs consisting of depression and anorexia. However, a decrease in number of eggs laid was observed in all virus-inoculated groups when compared to control hens. Evidence of infection was found in all chickens inoculated with the H6N2 virus by any of the three routes and the virus transmitted to contact hens. On the other hand, only one or two hens from each of the groups inoculated with the H9N2 virus shed detectable levels of virus, or seroconverted and did not transmit the virus to contacts, regardless of the route of inoculation. In conclusion, LPAI viruses can also infect chickens through other routes besides the IN route, which is considered the natural route of exposure. However, as seen with the H9N2 virus, the infectivity of the virus did not increase when given by these alternate routes.

Serologic evidence of avian metapneumovirus infection among adults occupationally exposed to Turkeys.

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Kayali, Ghazi; Ortiz, Ernesto J; Chorazy, Margaret L; Nagaraja, Kakambi V; DeBeauchamp, Jennifer; Webby, Richard J; Gray, Gregory C

2011-11-01

Genetically similar, the avian metapneumovirus (aMPV) and the human MPV (hMPV) are the only viruses in the Metapneumovirus genus. Previous research demonstrated the ability of hMPV to cause clinical disease in turkeys. In this controlled, cross-sectional, seroepidemiological study, we examined the hypothesis that aMPV might infect humans. We enrolled 95 adults occupationally exposed to turkeys and 82 nonexposed controls. Sera from study participants were examined for antibodies against aMPV and hMPV. Both in bivariate (OR=3.2; 95% CI: 1.1-9.2) and in multivariate modelling adjusting for antibody to hMPV (OR=4.1; 95% CI: 1.3-13.1), meat-processing workers were found to have an increased odds of previous infection with aMPV compared to controls. While hMPV antibody cross-reactivity is evident, these data suggest that occupational exposure to turkeys is a risk factor for human infection with aMPV. More studies are needed to validate these findings, to identify modes of aMPV transmission, and to determine risk factors associated with infection.

Draft Genome Sequences of Four Salmonella enterica subsp. enterica Serovar Enteritidis Strains Implicated in Infections of Avian and Human Hosts

KAUST Repository

An, Ran; Lin, Pengpeng; Bougouffa, Salim; Essack, Magbubah; Boxrud, David; Bajic, Vladimir B.; Vidovic, Sinisa

2018-01-01

Salmonella enterica subsp. enterica serovar Enteritidis is a wide-host-range pathogen. Occasionally, it is involved in invasive infections, leading to a high mortality rate. Here, we present the draft genome sequences of four S Enteritidis strains obtained from human and avian hosts that had been involved in bacteremia, gastroenteritis, and primary infections.

Draft Genome Sequences of Four Salmonella enterica subsp. enterica Serovar Enteritidis Strains Implicated in Infections of Avian and Human Hosts

KAUST Repository

An, Ran

2018-01-24

Salmonella enterica subsp. enterica serovar Enteritidis is a wide-host-range pathogen. Occasionally, it is involved in invasive infections, leading to a high mortality rate. Here, we present the draft genome sequences of four S Enteritidis strains obtained from human and avian hosts that had been involved in bacteremia, gastroenteritis, and primary infections.

Highly pathogenic avian influenza.

Science.gov (United States)

Swayne, D E; Suarez, D L

2000-08-01

Highly pathogenic (HP) avian influenza (AI) (HPAI) is an extremely contagious, multi-organ systemic disease of poultry leading to high mortality, and caused by some H5 and H7 subtypes of type A influenza virus, family Orthomyxoviridae. However, most AI virus strains are mildly pathogenic (MP) and produce either subclinical infections or respiratory and/or reproductive diseases in a variety of domestic and wild bird species. Highly pathogenic avian influenza is a List A disease of the Office International des Epizooties, while MPAI is neither a List A nor List B disease. Eighteen outbreaks of HPAI have been documented since the identification of AI virus as the cause of fowl plague in 1955. Mildly pathogenic avian influenza viruses are maintained in wild aquatic bird reservoirs, occasionally crossing over to domestic poultry and causing outbreaks of mild disease. Highly pathogenic avian influenza viruses do not have a recognised wild bird reservoir, but can occasionally be isolated from wild birds during outbreaks in domestic poultry. Highly pathogenic avian influenza viruses have been documented to arise from MPAI viruses through mutations in the haemagglutinin surface protein. Prevention of exposure to the virus and eradication are the accepted methods for dealing with HPAI. Control programmes, which imply allowing a low incidence of infection, are not an acceptable method for managing HPAI, but have been used during some outbreaks of MPAI. The components of a strategy to deal with MPAI or HPAI include surveillance and diagnosis, biosecurity, education, quarantine and depopulation. Vaccination has been used in some control and eradication programmes for AI.

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

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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.

A human-infecting H10N8 influenza virus retains a strong preference for avian-type receptors

NARCIS (Netherlands)

Zhang, Heng; de Vries, Robert P; Tzarum, Netanel; Zhu, Xueyong; Yu, Wenli; McBride, Ryan; Paulson, James C; Wilson, Ian A

2015-01-01

Recent avian-origin H10N8 influenza A viruses that have infected humans pose a potential pandemic threat. Alterations in the viral surface glycoprotein, hemagglutinin (HA), typically are required for influenza A viruses to cross the species barrier for adaptation to a new host, but whether H10N8

An overview on avian influenza

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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.

Draft genome sequences of three Escherichia coli strains with different In Vivo pathogenicities in an avian (Ascending) infection model of the oviduct

DEFF Research Database (Denmark)

Olsen, Rikke Heidemann; Thøfner, Ida; Pors, Susanne Elisabeth

2015-01-01

Here, we present three draft genome sequences of Escherichia coli strains that experimentally were proven to possess low (strain D2-2), intermediate (Chronic_salp), or high virulence (Cp6salp3) in an avian (ascending) infection model of the oviduct.......Here, we present three draft genome sequences of Escherichia coli strains that experimentally were proven to possess low (strain D2-2), intermediate (Chronic_salp), or high virulence (Cp6salp3) in an avian (ascending) infection model of the oviduct....

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

OpenAIRE

Bertran, Kateri; Pérez-Ramírez, Elisa; Busquets, Núria; Dolz, Roser; Ramis, Antoni; Abad, Francesc Xavier; Chaves, Aida; Vergara-Alert, Júlia; Barral, Marta; Höfle, Ursula; Majó, Natàlia

2011-01-01

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 bot...

Avian Schistosomes and Outbreaks of Cercarial Dermatitis

Science.gov (United States)

Mikeš, Libor; Lichtenbergová, Lucie; Skála, Vladimír; Soldánová, Miroslava; Brant, Sara Vanessa

2015-01-01

SUMMARY Cercarial dermatitis (swimmer's itch) is a condition caused by infective larvae (cercariae) of a species-rich group of mammalian and avian schistosomes. Over the last decade, it has been reported in areas that previously had few or no cases of dermatitis and is thus considered an emerging disease. It is obvious that avian schistosomes are responsible for the majority of reported dermatitis outbreaks around the world, and thus they are the primary focus of this review. Although they infect humans, they do not mature and usually die in the skin. Experimental infections of avian schistosomes in mice show that in previously exposed hosts, there is a strong skin immune reaction that kills the schistosome. However, penetration of larvae into naive mice can result in temporary migration from the skin. This is of particular interest because the worms are able to migrate to different organs, for example, the lungs in the case of visceral schistosomes and the central nervous system in the case of nasal schistosomes. The risk of such migration and accompanying disorders needs to be clarified for humans and animals of interest (e.g., dogs). Herein we compiled the most comprehensive review of the diversity, immunology, and epidemiology of avian schistosomes causing cercarial dermatitis. PMID:25567226

Troop education and avian influenza surveillance in military barracks in Ghana, 2011

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Odoom John

2012-11-01

Full Text Available Abstract Background Influenza A viruses that cause highly pathogenic avian influenza (HPAI also infect humans. In many developing countries such as Ghana, poultry and humans live in close proximity in both the general and military populations, increasing risk for the spread of HPAI from birds to humans. Respiratory infections such as influenza are especially prone to rapid spread among military populations living in close quarters such as barracks making this a key population for targeted avian influenza surveillance and public health education. Method Twelve military barracks situated in the coastal, tropical rain forest and northern savannah belts of the country were visited and the troops and their families educated on pandemic avian influenza. Attendants at each site was obtained from the attendance sheet provided for registration. The seminars focused on zoonotic diseases, influenza surveillance, pathogenesis of avian influenza, prevention of emerging infections and biosecurity. To help direct public health policies, a questionnaire was used to collect information on animal populations and handling practices from 102 households in the military barracks. Cloacal and tracheal samples were taken from 680 domestic and domesticated wild birds and analysed for influenza A using molecular methods for virus detection. Results Of the 1028 participants that took part in the seminars, 668 (65% showed good knowledge of pandemic avian influenza and the risks associated with its infection. Even though no evidence of the presence of avian influenza (AI infection was found in the 680 domestic and wild birds sampled, biosecurity in the households surveyed was very poor. Conclusion Active surveillance revealed that there was no AI circulation in the military barracks in April 2011. Though participants demonstrated good knowledge of pandemic avian influenza, biosecurity practices were minimal. Sustained educational programs are needed to further strengthen

Avian influenza A virus and Newcastle disease virus mono- and co-infections in birds

Directory of Open Access Journals (Sweden)

Iv. Zarkov

2017-06-01

Full Text Available The main features of avian influenza viruses (AIV and Newcastle disease virus (APMV-1, the possibilities for isolation and identification in laboratory conditions, methods of diagnostics, main hosts, clinical signs and virus shedding are reviewed in chronological order. The other part of the review explains the mechanisms and interactions in cases of co-infection of AIV and APMV-1, either between them or with other pathogens in various indicator systems – cell cultures, chick embryos or birds. The emphasis is placed on quantitative data on the virus present mainly in the first ten days following experimental infection of birds, the periods of virus carrier ship and shedding, clinical signs, pathological changes, diagnostic challenges

(Highly pathogenic) avian influenza as a zoonotic agent.

Science.gov (United States)

Kalthoff, Donata; Globig, Anja; Beer, Martin

2010-01-27

Zoonotic agents challenging the world every year afresh are influenza A viruses. In the past, human pandemics caused by influenza A viruses had been occurring periodically. Wild aquatic birds are carriers of the full variety of influenza virus A subtypes, and thus, most probably constitute the natural reservoir of all influenza A viruses. Whereas avian influenza viruses in their natural avian reservoir are generally of low pathogenicity (LPAIV), some have gained virulence by mutation after transmission and adaptation to susceptible gallinaceous poultry. Those so-called highly pathogenic avian influenza viruses (HPAIV) then cause mass die-offs in susceptible birds and lead to tremendous economical losses when poultry is affected. Besides a number of avian influenza virus subtypes that have sporadically infected mammals, the HPAIV H5N1 Asia shows strong zoonotic characteristics and it was transmitted from birds to different mammalian species including humans. Theoretically, pandemic viruses might derive directly from avian influenza viruses or arise after genetic reassortment between viruses of avian and mammalian origin. So far, HPAIV H5N1 already meets two conditions for a pandemic virus: as a new subtype it has been hitherto unseen in the human population and it has infected at least 438 people, and caused severe illness and high lethality in 262 humans to date (August 2009). The acquisition of efficient human-to-human transmission would complete the emergence of a new pandemic virus. Therefore, fighting H5N1 at its source is the prerequisite to reduce pandemic risks posed by this virus. Other influenza viruses regarded as pandemic candidates derive from subtypes H2, H7, and H9 all of which have infected humans in the past. Here, we will give a comprehensive overview on avian influenza viruses in concern to their zoonotic potential. Copyright 2009 Elsevier B.V. All rights reserved.

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....

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...... and AIV virus was found, and this difference was in accordance with the distribution of the SA-alpha-2,6 and SA-alpha-2,3 receptor, respectively. The results indicated that the distribution of influenza A virus receptors in pigs are similar to that of humans and therefore challenge the theory that the pig...

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 AIV virus was found, and this difference was in accordance with the distribution of the SA-alpha-2,6 and SA-alpha-2,3 receptor, respectively. The results indicated that the distribution of influenza A virus receptors in pigs are similar to that of humans and therefore challenge the theory that the pig...

On avian influenza epidemic models with time delay.

Science.gov (United States)

Liu, Sanhong; Ruan, Shigui; Zhang, Xinan

2015-12-01

After the outbreak of the first avian influenza A virus (H5N1) in Hong Kong in 1997, another avian influenza A virus (H7N9) crossed the species barrier in mainland China in 2013 and 2014 and caused more than 400 human cases with a death rate of nearly 40%. In this paper, we take account of the incubation periods of avian influenza A virus and construct a bird-to-human transmission model with different time delays in the avian and human populations combining the survival probability of the infective avian and human populations at the latent time. By analyzing the dynamical behavior of the model, we obtain a threshold value for the prevalence of avian influenza and investigate local and global asymptotical stability of equilibria of the system.

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

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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. Copyright © 2014 Elsevier B.V. All rights reserved.

Avian cholera

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Friend, Milton

1999-01-01

Avian cholera is a contagious disease resulting from infection by the bacterium Pasteurella multocida. Several subspecies of bacteria have been proposed for P. multocida, and at least 16 different P. multocida serotypes or characteristics of antigens in bacterial cells that differentiate bacterial variants from each other have been recognized. The serotypes are further differentiated by other methods, including DNA fingerprinting. These evaluations are useful for studying the ecology of avian cholera (Fig. 7.1), because different serotypes are generally found in poultry and free-ranging migratory birds. These evaluations also show that different P. multocida serotypes are found in wild birds in the eastern United States than those that are found in the birds in the rest of the Nation (Fig. 7.2).

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

OpenAIRE

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

2015-01-01

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-Oc...

Avian metapneumovirus subtype B experimental infection and tissue distribution in chickens, sparrows, and pigeons.

Science.gov (United States)

Gharaibeh, S; Shamoun, M

2012-07-01

Avian metapneumovirus (aMPV) is a respiratory virus that infects a range of avian hosts, including chickens and turkeys. Migratory and local wild birds are implicated in aMPV spread among farms, countries, and seasonal outbreaks of the disease. A subtype B aMPV isolate from commercial chicken flocks suffering from respiratory disease was experimentally inoculated oculonasally into 7-week old chickens, young pigeons, and sparrows. Chickens showed minimal tracheal rales, whereas pigeons and sparrows were asymptomatic. Shedding of aMPV was detected by reverse transcription polymerase chain reaction on homogenates from nasal turbinates. At 5 days postinfection, 5 of 5 chickens, 2 of 5 pigeons, and 1 of 5 sparrows were positive; at 10 or 15 days, none were positive. At 2 and 5 days, aMPV antigens were localized at the ciliated boarder of respiratory epithelium in nasal cavity and trachea of chickens, as well as to the conjunctival epithelium. Pigeons had detectable viral antigens in only the trachea at 2 and 5 days; sparrow tissues did not show any positive staining. At the end of the experiment, at 21 days postinfection, 14 of 15 inoculated chickens seroconverted against aMPV, but none of the inoculated pigeons or sparrows did. The authors believe that pigeons and sparrows have the ability to transmit the virus between chicken farms, although they do not consider pigeons and sparrows as natural hosts for aMPV, given that they failed to seroconvert. In conclusion, pigeons and sparrows are partially susceptible to aMPV infection, probably acting more as mechanical vectors because infection is only temporary and short-lived.

Avian Influenza virus glycoproteins restrict virus replication and spread through human airway epithelium at temperatures of the proximal airways.

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Margaret A Scull

2009-05-01

Full Text Available Transmission of avian influenza viruses from bird to human is a rare event even though avian influenza viruses infect the ciliated epithelium of human airways in vitro and ex vivo. Using an in vitro model of human ciliated airway epithelium (HAE, we demonstrate that while human and avian influenza viruses efficiently infect at temperatures of the human distal airways (37 degrees C, avian, but not human, influenza viruses are restricted for infection at the cooler temperatures of the human proximal airways (32 degrees C. These data support the hypothesis that avian influenza viruses, ordinarily adapted to the temperature of the avian enteric tract (40 degrees C, rarely infect humans, in part due to differences in host airway regional temperatures. Previously, a critical residue at position 627 in the avian influenza virus polymerase subunit, PB2, was identified as conferring temperature-dependency in mammalian cells. Here, we use reverse genetics to show that avianization of residue 627 attenuates a human virus, but does not account for the different infection between 32 degrees C and 37 degrees C. To determine the mechanism of temperature restriction of avian influenza viruses in HAE at 32 degrees C, we generated recombinant human influenza viruses in either the A/Victoria/3/75 (H3N2 or A/PR/8/34 (H1N1 genetic background that contained avian or avian-like glycoproteins. Two of these viruses, A/Victoria/3/75 with L226Q and S228G mutations in hemagglutinin (HA and neuraminidase (NA from A/Chick/Italy/1347/99 and A/PR/8/34 containing the H7 and N1 from A/Chick/Italy/1347/99, exhibited temperature restriction approaching that of wholly avian influenza viruses. These data suggest that influenza viruses bearing avian or avian-like surface glycoproteins have a reduced capacity to establish productive infection at the temperature of the human proximal airways. This temperature restriction may limit zoonotic transmission of avian influenza viruses and

Different intracellular distribution of avian reovirus core protein sigmaA in cells of avian and mammalian origin

International Nuclear Information System (INIS)

Vázquez-Iglesias, Lorena; Lostalé-Seijo, Irene; Martínez-Costas, José; Benavente, Javier

2012-01-01

A comparative analysis of the intracellular distribution of avian reovirus (ARV) core protein sigmaA in cells of avian and mammalian origin revealed that, whereas the viral protein accumulates in the cytoplasm and nucleolus of avian cells, most sigmaA concentrates in the nucleoplasm of mammalian cells in tight association with the insoluble nuclear matrix fraction. Our results further showed that sigmaA becomes arrested in the nucleoplasm of mammalian cells via association with mammalian cell-specific factors and that this association prevents nucleolar targeting. Inhibition of RNA polymerase II activity, but not of RNA polymerase I activity, in infected mammalian cells induces nucleus-to-cytoplasm sigmaA translocation through a CRM1- and RanGTP-dependent mechanism, yet a heterokaryon assay suggests that sigmaA does not shuttle between the nucleus and cytoplasm. The scarcity of sigmaA in cytoplasmic viral factories of infected mammalian cells could be one of the factors contributing to limited ARV replication in mammalian cells.

Different intracellular distribution of avian reovirus core protein sigmaA in cells of avian and mammalian origin

Energy Technology Data Exchange (ETDEWEB)

Vazquez-Iglesias, Lorena; Lostale-Seijo, Irene; Martinez-Costas, Jose [Departamento de Bioquimica y Biologia Molecular, Facultad de Farmacia, y Centro Singular de Investigacion en Quimica Biologica y Materiales Moleculares (CIQUS), Universidad de Santiago de Compostela, 15782-Santiago de Compostela (Spain); Benavente, Javier, E-mail: franciscojavier.benavente@usc.es [Departamento de Bioquimica y Biologia Molecular, Facultad de Farmacia, y Centro Singular de Investigacion en Quimica Biologica y Materiales Moleculares (CIQUS), Universidad de Santiago de Compostela, 15782-Santiago de Compostela (Spain)

2012-10-25

A comparative analysis of the intracellular distribution of avian reovirus (ARV) core protein sigmaA in cells of avian and mammalian origin revealed that, whereas the viral protein accumulates in the cytoplasm and nucleolus of avian cells, most sigmaA concentrates in the nucleoplasm of mammalian cells in tight association with the insoluble nuclear matrix fraction. Our results further showed that sigmaA becomes arrested in the nucleoplasm of mammalian cells via association with mammalian cell-specific factors and that this association prevents nucleolar targeting. Inhibition of RNA polymerase II activity, but not of RNA polymerase I activity, in infected mammalian cells induces nucleus-to-cytoplasm sigmaA translocation through a CRM1- and RanGTP-dependent mechanism, yet a heterokaryon assay suggests that sigmaA does not shuttle between the nucleus and cytoplasm. The scarcity of sigmaA in cytoplasmic viral factories of infected mammalian cells could be one of the factors contributing to limited ARV replication in mammalian cells.

Tropism and Infectivity of Influenza Virus, Including Highly Pathogenic Avian H5N1 Virus, in Ferret Tracheal Differentiated Primary Epithelial Cell Cultures

Science.gov (United States)

Zeng, Hui; Goldsmith, Cynthia S.; Maines, Taronna R.; Belser, Jessica A.; Gustin, Kortney M.; Pekosz, Andrew; Zaki, Sherif R.; Katz, Jacqueline M.

2013-01-01

Tropism and adaptation of influenza viruses to new hosts is partly dependent on the distribution of the sialic acid (SA) receptors to which the viral hemagglutinin (HA) binds. Ferrets have been established as a valuable in vivo model of influenza virus pathogenesis and transmission because of similarities to humans in the distribution of HA receptors and in clinical signs of infection. In this study, we developed a ferret tracheal differentiated primary epithelial cell culture model that consisted of a layered epithelium structure with ciliated and nonciliated cells on its apical surface. We found that human-like (α2,6-linked) receptors predominated on ciliated cells, whereas avian-like (α2,3-linked) receptors, which were less abundant, were presented on nonciliated cells. When we compared the tropism and infectivity of three human (H1 and H3) and two avian (H1 and H5) influenza viruses, we observed that the human influenza viruses primarily infected ciliated cells and replicated efficiently, whereas a highly pathogenic avian H5N1 virus (A/Vietnam/1203/2004) replicated efficiently within nonciliated cells despite a low initial infection rate. Furthermore, compared to other influenza viruses tested, VN/1203 virus replicated more efficiently in cells isolated from the lower trachea and at a higher temperature (37°C) compared to a lower temperature (33°C). VN/1203 virus infection also induced higher levels of immune mediator genes and cell death, and virus was recovered from the basolateral side of the cell monolayer. This ferret tracheal differentiated primary epithelial cell culture system provides a valuable in vitro model for studying cellular tropism, infectivity, and the pathogenesis of influenza viruses. PMID:23255802

Exo-erythrocytic development of avian malaria and related haemosporidian parasites.

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Valkiūnas, Gediminas; Iezhova, Tatjana A

2017-03-03

Avian malaria parasites (Plasmodium spp.) and related haemosporidians (Haemosporida) are responsible for diseases which can be severe and even lethal in avian hosts. These parasites cause not only blood pathology, but also damage various organs due to extensive exo-erythrocytic development all over the body, which is not the case during Plasmodium infections in mammals. However, exo-erythrocytic development (tissue merogony or schizogony) remains the most poorly investigated part of life cycle in all groups of wildlife haemosporidian parasites. In spite of remarkable progress in studies of genetic diversity, ecology and evolutionary biology of avian haemosporidians during the past 20 years, there is not much progress in understanding patterns of exo-erythrocytic development in these parasites. The purpose of this review is to overview the main information on exo-erythrocytic development of avian Plasmodium species and related haemosporidian parasites as a baseline for assisting academic and veterinary medicine researchers in morphological identification of these parasites using tissue stages, and to define future research priorities in this field of avian malariology. The data were considered from peer-reviewed articles and histological material that was accessed in zoological collections in museums of Australia, Europe and the USA. Articles describing tissue stages of avian haemosporidians were included from 1908 to the present. Histological preparations of various organs infected with the exo-erythrocytic stages of different haemosporidian parasites were examined. In all, 229 published articles were included in this review. Exo-erythrocytic stages of avian Plasmodium, Fallisia, Haemoproteus, Leucocytozoon, and Akiba species were analysed, compared and illustrated. Morphological characters of tissue stages that can be used for diagnostic purposes were specified. Recent molecular studies combined with histological research show that avian haemosporidians are more

PCR diagnostics underestimate the prevalence of avian malaria (Plasmodium relictum) in experimentally-infected passerines

Science.gov (United States)

Jarvi, Susan I.; Schultz, Jeffrey J.; Atkinson, Carter T.

2002-01-01

Several polymerase chain reaction (PCR)-based methods have recently been developed for diagnosing malarial infections in both birds and reptiles, but a critical evaluation of their sensitivity in experimentally-infected hosts has not been done. This study compares the sensitivity of several PCR-based methods for diagnosing avian malaria (Plasmodium relictum) in captive Hawaiian honeycreepers using microscopy and a recently developed immunoblotting technique. Sequential blood samples were collected over periods of up to 4.4 yr after experimental infection and rechallenge to determine both the duration and detectability of chronic infections. Two new nested PCR approaches for detecting circulating parasites based on P. relictum 18S rRNA genes and the thrombospondin-related anonymous protein (TRAP) gene are described. The blood smear and the PCR tests were less sensitive than serological methods for detecting chronic malarial infections. Individually, none of the diagnostic methods was 100% accurate in detecting subpatent infections, although serological methods were significantly more sensitive (97%) than either nested PCR (61–84%) or microscopy (27%). Circulating parasites in chronically infected birds either disappear completely from circulation or to drop to intensities below detectability by nested PCR. Thus, the use of PCR as a sole means of detection of circulating parasites may significantly underestimate true prevalence.

Detection of Avian coronavirus infectious bronchitis virus type QX infection in Switzerland.

Science.gov (United States)

Sigrist, Brigitte; Tobler, Kurt; Schybli, Martina; Konrad, Leonie; Stöckli, René; Cattoli, Giovanni; Lüschow, Dörte; Hafez, Hafez M; Britton, Paul; Hoop, Richard K; Vögtlin, Andrea

2012-11-01

Infectious bronchitis, a disease of chickens caused by Avian coronavirus infectious bronchitis virus (IBV), leads to severe economic losses for the poultry industry worldwide. Various attempts to control the virus based on vaccination strategies are performed. However, due to the emergence of novel genotypes, an effective control of the virus is hindered. In 1996, a novel viral genotype named IBV-QX was reported for the first time in Qingdao, Shandong province, China. The first appearance of an IBV-QX isolate in Europe was reported between 2003 and 2004 in The Netherlands. Subsequently, infections with this genotype were found in several other European countries such as France, Italy, Germany, United Kingdom, Slovenia, and Sweden. The present report describes the use of a new set of degenerate primers that amplify a 636-bp fragment within the S1 gene by reverse transcription polymerase chain reaction to detect the occurrence of IBV-QX infection in Switzerland.

Explaining variance of avian malaria infection in the wild: the importance of host density, habitat, individual life-history and oxidative stress.

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Isaksson, Caroline; Sepil, Irem; Baramidze, Vladimer; Sheldon, Ben C

2013-04-08

Avian malaria (Plasmodium sp.) is globally widespread, but considerable variation exists in infection (presence/absence) patterns at small spatial scales. This variation can be driven by variation in ecology, demography, and phenotypic characters, in particular those that influence the host's resistance. Generation of reactive oxygen species (ROS) is one of the host's initial immune responses to combat parasitic invasion. However, long-term ROS exposure can harm the host and the redox response therefore needs to be adjusted according to infection stage and host phenotype. Here we use experimental and correlational approaches to assess the relative importance of host density, habitat composition, individual level variation and redox physiology for Plasmodium infection in a wild population of great tits, Parus major. We found that 36% of the great tit population was infected with Plasmodium (22% P. relictum and 15% P. circumflexum prevalence) and that patterns of infection were Plasmodium species-specific. First, the infection of P. circumflexum was significantly higher in areas with experimental increased host density, whereas variation in P. relictum infection was mainly attributed to age, sex and reproduction. Second, great tit antioxidant responses - total and oxidizied glutathione - showed age- , sex- and Plasmodium species-specific patterns between infected and uninfected individuals, but reactive oxygen metabolites (ROM) showed only a weak explanatory power for patterns of P. relictum infection. Instead ROM significantly increased with Plasmodium parasitaemia. These results identify some key factors that influence Plasmodium infection in wild birds, and provide a potential explanation for the underlying physiological basis of recently documented negative effects of chronic avian malaria on survival and reproductive success.

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.

Human Infection with Highly Pathogenic Avian Influenza A(H7N9) Virus, China.

Science.gov (United States)

Ke, Changwen; Mok, Chris Ka Pun; Zhu, Wenfei; Zhou, Haibo; He, Jianfeng; Guan, Wenda; Wu, Jie; Song, Wenjun; Wang, Dayan; Liu, Jiexiong; Lin, Qinhan; Chu, Daniel Ka Wing; Yang, Lei; Zhong, Nanshan; Yang, Zifeng; Shu, Yuelong; Peiris, Joseph Sriyal Malik

2017-07-01

The recent increase in zoonotic avian influenza A(H7N9) disease in China is a cause of public health concern. Most of the A(H7N9) viruses previously reported have been of low pathogenicity. We report the fatal case of a patient in China who was infected with an A(H7N9) virus having a polybasic amino acid sequence at its hemagglutinin cleavage site (PEVPKRKRTAR/GL), a sequence suggestive of high pathogenicity in birds. Its neuraminidase also had R292K, an amino acid change known to be associated with neuraminidase inhibitor resistance. Both of these molecular features might have contributed to the patient's adverse clinical outcome. The patient had a history of exposure to sick and dying poultry, and his close contacts had no evidence of A(H7N9) disease, suggesting human-to-human transmission did not occur. Enhanced surveillance is needed to determine whether this highly pathogenic avian influenza A(H7N9) virus will continue to spread.

Replication of avian influenza A viruses in mammals.

OpenAIRE

Hinshaw, V S; Webster, R G; Easterday, B C; Bean, W J

1981-01-01

The recent appearance of an avian influenza A virus in seals suggests that viruses are transmitted from birds to mammals in nature. To examine this possibility, avian viruses of different antigenic subtypes were evaluated for their ability to replicate in three mammals-pigs, ferrets, and cats. In each of these mammals, avian strains replicated to high titers in the respiratory tract (10(5) to 10(7) 50% egg infective doses per ml of nasal wash), with peak titers at 2 to 4 days post-inoculation...

Investigation of avian influenza infections in wild birds, poultry and humans in Eastern Dongting Lake, China.

Science.gov (United States)

Shi, Jinghong; Gao, Lidong; Zhu, Yun; Chen, Tao; Liu, Yunzhi; Dong, Libo; Liu, Fuqiang; Yang, Hao; Cai, Yahui; Yu, Mingdong; Yao, Yi; Xu, Cuilin; Xiao, Xiangming; Shu, Yuelong

2014-01-01

We investigated avian influenza infections in wild birds, poultry, and humans at Eastern Dongting Lake, China. We analyzed 6,621 environmental samples, including fresh fecal and water samples, from wild birds and domestic ducks that were collected from the Eastern Dongting Lake area from November 2011 to April 2012. We also conducted two cross-sectional serological studies in November 2011 and April 2012, with 1,050 serum samples collected from people exposed to wild birds and/or domestic ducks. Environmental samples were tested for the presence of avian influenza virus (AIV) using quantitative PCR assays and virus isolation techniques. Hemagglutination inhibition assays were used to detect antibodies against AIV H5N1, and microneutralization assays were used to confirm these results. Among the environmental samples from wild birds and domestic ducks, AIV prevalence was 5.19 and 5.32%, respectively. We isolated 39 and 5 AIVs from the fecal samples of wild birds and domestic ducks, respectively. Our analysis indicated 12 subtypes of AIV were present, suggesting that wild birds in the Eastern Dongting Lake area carried a diverse array of AIVs with low pathogenicity. We were unable to detect any antibodies against AIV H5N1 in humans, suggesting that human infection with H5N1 was rare in this region.

Avian Influenza Virus Glycoproteins Restrict Virus Replication and Spread through Human Airway Epithelium at Temperatures of the Proximal Airways

OpenAIRE

Scull, Margaret A.; Gillim-Ross, Laura; Santos, Celia; Roberts, Kim L.; Bordonali, Elena; Subbarao, Kanta; Barclay, Wendy S.; Pickles, Raymond J.

2009-01-01

Transmission of avian influenza viruses from bird to human is a rare event even though avian influenza viruses infect the ciliated epithelium of human airways in vitro and ex vivo. Using an in vitro model of human ciliated airway epithelium (HAE), we demonstrate that while human and avian influenza viruses efficiently infect at temperatures of the human distal airways (37 degrees C), avian, but not human, influenza viruses are restricted for infection at the cooler temperatures of the human p...

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 ducks seroconverted in a range of serological tests by 15 days post inoculation. Virus was efficiently transmitted during acute infection (5 inoculation-infected to all 5 contact ducks). However, no evidence for transmission, as determined by seroconversion and viral shedding, was found between an inoculation-infected group (n = 10) and contact ducks (n = 9) when the two groups only had contact after 10 days post inoculation. Clinical disease was more frequent and more severe in contact-infected (2 of 5) than inoculation-infected ducks (1 of 15). We conclude that Indonesian clade 2.1 H5N1 highly pathogenic avian influenza virus does not persist in individual ducks after acute infection.

Nonlinear dynamics of avian influenza epidemic models.

Science.gov (United States)

Liu, Sanhong; Ruan, Shigui; Zhang, Xinan

2017-01-01

Avian influenza is a zoonotic disease caused by the transmission of the avian influenza A virus, such as H5N1 and H7N9, from birds to humans. The avian influenza A H5N1 virus has caused more than 500 human infections worldwide with nearly a 60% death rate since it was first reported in Hong Kong in 1997. The four outbreaks of the avian influenza A H7N9 in China from March 2013 to June 2016 have resulted in 580 human cases including 202 deaths with a death rate of nearly 35%. In this paper, we construct two avian influenza bird-to-human transmission models with different growth laws of the avian population, one with logistic growth and the other with Allee effect, and analyze their dynamical behavior. We obtain a threshold value for the prevalence of avian influenza and investigate the local or global asymptotical stability of each equilibrium of these systems by using linear analysis technique or combining Liapunov function method and LaSalle's invariance principle, respectively. Moreover, we give necessary and sufficient conditions for the occurrence of periodic solutions in the avian influenza system with Allee effect of the avian population. Numerical simulations are also presented to illustrate the theoretical results. Copyright © 2016 Elsevier Inc. All rights reserved.

Occurrence of avian Plasmodium and West Nile virus in culex species in Wisconsin

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Hughes, T.; Irwin, P.; Hofmeister, E.; Paskewitz, S.M.

2010-01-01

The occurrence of multiple pathogens in mosquitoes and birds could affect the dynamics of disease transmission. We collected adult Culex pipiens and Cx. restuans (Cx. pipiens/restuans hereafter) from sites in Wisconsin and tested them for West Nile virus (WNV) and for avian malaria (Plasmodium). Gravid Cx. pipiens/restuans were tested for WNV using a commercial immunoassay, the RAMP?? WNV test, and positive results were verified by reverse transcriptasepolymerase chain reaction. There were 2 WNV-positive pools of Cx. pipiens/restuans in 2006 and 1 in 2007. Using a bias-corrected maximum likelihood estimation, the WNV infection rate for Cx. pipiens/restuans was 5.48/1,000 mosquitoes in 2006 and 1.08/1,000 mosquitoes in 2007. Gravid Cx. pipiens or Cx. restuans were tested individually for avian Plasmodium by a restriction enzymebased assay. Twelve mosquitoes were positive for avian Plasmodium (10.0), 2 were positive for Haemoproteus, and 3 were positive for Leucocytozoon. There were 4 mixed infections, with mosquitoes positive for >1 of the hemosporidian parasites. This work documents a high rate of hemosporidian infection in Culex spp. and illustrates the potential for co-infections with other arboviruses in bird-feeding mosquitoes and their avian hosts. In addition, hemosporidian infection rates may be a useful tool for investigating the ecological dynamics of Culex/avian interactions. ?? 2010 by The American Mosquito Control Association, Inc.

The chest X-ray manifestations of children with highly pathogenic H5N1 avian influenza virus infection (a report of 1 final diagnosis case and 1 borderline case)

International Nuclear Information System (INIS)

Jin Ke; Chen Hua; Tan Lihua; Yuan Youhong; Xiao Enhua; Luo Ruping; Li Wanging; Xu Heping

2006-01-01

Objective: To describe the chest X-ray manifestations of children with highly pathogenic H5N1 avian influenza virus infection. Methods: The pulmonary X-ray findings in 1 patient was confirmed by the World Health Organization infected H5N1 avian influenza vires and 1 borderline patient was retrospectively analyzed. Results: Both sides of lung field showed the cloudy and massive infiltration in chest X-ray film. The lesions of lung distributed extensively and symmetrically. Radiological dynamic changes showed the variation of the lesions of lung was quick in a short time. It had a characteristic of roving around. The lesions of lung appeared fibrosis at the period of the end. Conclusion: There are some radiographic characteristics in children with H5N1 avian influenza vires infection. It will be helpful for its diagnosis when getting familiar with its X-ray manifestations, but the final diagnosis is dependent on the epidemiology history and laboratory results. (authors)

Thymus transcriptome reveals novel pathways in response to avian pathogenic Escherichia coli infection.

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Sun, H; Liu, P; Nolan, L K; Lamont, S J

2016-12-01

Avian pathogenic Escherichia coli (APEC) can cause significant morbidity in chickens. The thymus provides the essential environment for T cell development; however, the thymus transcriptome has not been examined for gene expression in response to APEC infection. An improved understanding of the host genomic response to APEC infection could inform future breeding programs for disease resistance and APEC control. We therefore analyzed the transcriptome of the thymus of birds challenged with APEC, contrasting susceptible and resistant phenotypes. Thousands of genes were differentially expressed in birds of the 5-day post infection (dpi) challenged-susceptible group vs. 5 dpi non-challenged, in 5 dpi challenged-susceptible vs. 5 dpi challenged-resistant birds, as well as in 5 dpi vs. one dpi challenged-susceptible birds. The Toll-like receptor signaling pathway was the major innate immune response for birds to respond to APEC infection. Moreover, lysosome and cell adhesion molecules pathways were common mechanisms for chicken response to APEC infection. The T-cell receptor signaling pathway, cell cycle, and p53 signaling pathways were significantly activated in resistant birds to resist APEC infection. These results provide a comprehensive assessment of global gene networks and biological functionalities of differentially expressed genes in the thymus under APEC infection. These findings provide novel insights into key molecular genetic mechanisms that differentiate host resistance from susceptibility in this primary lymphoid tissue, the thymus. © The Author 2016. Published by Oxford University Press on behalf of Poultry Science Association.

Epidemiology of human infections with highly pathogenic avian influenza A(H7N9) virus in Guangdong, 2016 to 2017.

Science.gov (United States)

Kang, Min; Lau, Eric H Y; Guan, Wenda; Yang, Yuwei; Song, Tie; Cowling, Benjamin J; Wu, Jie; Peiris, Malik; He, Jianfeng; Mok, Chris Ka Pun

2017-07-06

We describe the epidemiology of highly pathogenic avian influenza (HPAI) A(H7N9) based on poultry market environmental surveillance and laboratory-confirmed human cases (n = 9) in Guangdong, China. We also compare the epidemiology between human cases of high- and low-pathogenic avian influenza A(H7N9) (n = 51) in Guangdong. Case fatality and severity were similar. Touching sick or dead poultry was the most important risk factor for HPAI A(H7N9) infections and should be highlighted for the control of future influenza A(H7N9) epidemics. This article is copyright of The Authors, 2017.

Avian cholera in waterfowl: the role of lesser snow and Ross's geese as carriers of avian cholera in the Playa Lakes region

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Samuel, M.D.; Shadduck, D.J.; Goldberg, Diana R.; Johnson, W.P.

2005-01-01

We collected samples from apparently healthy geese in the Playa Lakes Region (USA) during the winters of 2000a??01 and 2001a??02 to determine whether carriers of Pasteurella multocida, the bacterium that causes avian cholera, were present in wild populations. With the use of methods developed in laboratory challenge trials (Samuel et al., 2003a) and a serotype-specific polymerase chain reaction method for identification of P. multocida serotype 1, we found that a small proportion of 322 wild birds (cholera infection. Our results confirm the hypothesis that wild waterfowl are carriers of avian cholera and add support for the hypothesis that wild birds are a reservoir for this disease. In concert with other research, this work indicates that enzootic infection with avian cholera occurs in lesser snow goose (Chen caerulescens caerulescens) populations throughout their annual cycle. Although fewer Rossa??s geese (Chen rossii) were sampled, we also found these birds were carriers of P. multocida. Even in the absence of disease outbreaks, serologic evidence indicates that chronic disease transmission and recent infection are apparently occurring year-round in these highly gregarious birds and that a small portion of these populations are potential carriers with active infection.

The Pathology of Avian Influenza in Birds and Animals: An Analytical Review

International Nuclear Information System (INIS)

Ryabchikova, E. I.; Getmanova, T. N.

2007-01-01

Influenza virus remains enigmatic despite of long extensive studies. Avian influenza virus (H5N1) is able to infect a large spectrum of animal and bird species. Highly pathogenic avian influenza virus represents a serious problem both for a human and birds, particularly for chicks. Many studies have been performed in order to show differences between highly and low pathogenic avian influenza H5N1 viruses, and examine their biological properties. Many separate pathological and microscopic descriptions are interspersed in numerous published articles. The aim of our study was to analyze data published in international scientific journals, and to attempt a generalized view of avian influenza pathology in various animal and bird hosts. We summarized and systematized data describing pathological changes caused by both highly and low pathogenic types of avian influenza virus (H5N1) in animals and birds, and developed generalized descriptions with accent at the type of virus. We also tried to show up species specific features of pathological changes in birds and animals infected with avian influenza virus (H5N1). The results of this analytical work may be useful for pathological studies of a new avian influenza virus isolates, and for understanding of avian influenza pathogenesis in birds and animals. (author)

Avian Influenza.

Science.gov (United States)

Zeitlin, Gary Adam; Maslow, Melanie Jane

2005-05-01

The current epidemic of H5N1 highly pathogenic avian influenza in Southeast Asia raises serious concerns that genetic reassortment will result in the next influenza pandemic. There have been 164 confirmed cases of human infection with avian influenza since 1996. In 2004, there were 45 cases of human H5N1 in Vietnam and Thailand, with a mortality rate more than 70%. In addition to the potential public health hazard, the current zoonotic epidemic has caused severe economic losses. Efforts must be concentrated on early detection of bird outbreaks with aggressive culling, quarantining, and disinfection. To prepare for and prevent an increase in human cases, it is essential to improve detection methods and stockpile effective antivirals. Novel therapeutic modalities, including short-interfering RNAs and new vaccine strategies that use plasmid-based genetic systems, offer promise should a pandemic occur.

Ecology and diagnosis of introduced avian malaria in Hawaiian forest birds

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Atkinson, Carter T.

2005-01-01

Avian malaria is a disease caused by species of protozoan parasites (Plasmodium) that infect birds. Related species commonly infect reptiles, birds and mammals in tropical and temperate regions of the world. Transmitted by mosquitoes, the parasites spend part of their lives in the red blood cells of birds (Figure 1). Avian malaria is common in continental areas, but is absent from the most isolated island archipelagos where mosquitoes do not naturally occur. More than 40 different species of avian Plasmodium have been described, but only one, P. relictum, has been introduced to the Hawaiian Islands. Because they evolved without natural exposure to avian malaria, native Hawaiian honeycreepers are extremely susceptible to this disease. Malaria currently limits the geographic distribution of native species, has population level impacts on survivorship, and is limiting the recovery of threatened and endangered species of forest birds.

Emergence of a Novel Avian Pox Disease in British Tit Species

OpenAIRE

Lawson, Becki; Lachish, Shelly; Colvile, Katie M.; Durrant, Chris; Peck, Kirsi M.; Toms, Mike P.; Sheldon, Ben C.; Cunningham, Andrew A.

2012-01-01

Avian pox is a viral disease with a wide host range. In Great Britain, avian pox in birds of the Paridae family was first diagnosed in a great tit (Parus major) from south-east England in 2006. An increasing number of avian pox incidents in Paridae have been reported each year since, indicative of an emergent infection. Here, we utilise a database of opportunistic reports of garden bird mortality and morbidity to analyse spatial and temporal patterns of suspected avian pox throughout Great Br...

Chromosomal features of Escherichia coli serotype O2:K2, an avian pathogenic E. coli

DEFF Research Database (Denmark)

Jørgensen, Steffen L; Kudirkiene, Egle; Li, Lili

2017-01-01

Escherichia coli causing infection outside the gastrointestinal system are referred to as extra-intestinal pathogenic E. coli. Avian pathogenic E. coli is a subgroup of extra-intestinal pathogenic E. coli and infections due to avian pathogenic E. coli have major impact on poultry production econo...

Host behaviour and physiology underpin individual variation in avian influenza virus infection in migratory Bewick's swans.

Science.gov (United States)

Hoye, Bethany J; Fouchier, Ron A M; Klaassen, Marcel

2012-02-07

Individual variation in infection modulates both the dynamics of pathogens and their impact on host populations. It is therefore crucial to identify differential patterns of infection and understand the mechanisms responsible. Yet our understanding of infection heterogeneity in wildlife is limited, even for important zoonotic host-pathogen systems, owing to the intractability of host status prior to infection. Using novel applications of stable isotope ecology and eco-immunology, we distinguish antecedent behavioural and physiological traits associated with avian influenza virus (AIV) infection in free-living Bewick's swans (Cygnus columbianus bewickii). Swans infected with AIV exhibited higher serum δ13C (-25.3±0.4) than their non-infected counterparts (-26.3±0.2). Thus, individuals preferentially foraging in aquatic rather than terrestrial habitats experienced a higher risk of infection, suggesting that the abiotic requirements of AIV give rise to heterogeneity in pathogen exposure. Juveniles were more likely to be infected (30.8% compared with 11.3% for adults), shed approximately 15-fold higher quantity of virus and exhibited a lower specific immune response than adults. Together, these results demonstrate the potential for heterogeneity in infection to have a profound influence on the dynamics of pathogens, with concomitant impacts on host habitat selection and fitness.

The threshold of a stochastic avian-human influenza epidemic model with psychological effect

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Zhang, Fengrong; Zhang, Xinhong

2018-02-01

In this paper, a stochastic avian-human influenza epidemic model with psychological effect in human population and saturation effect within avian population is investigated. This model describes the transmission of avian influenza among avian population and human population in random environments. For stochastic avian-only system, persistence in the mean and extinction of the infected avian population are studied. For the avian-human influenza epidemic system, sufficient conditions for the existence of an ergodic stationary distribution are obtained. Furthermore, a threshold of this stochastic model which determines the outcome of the disease is obtained. Finally, numerical simulations are given to support the theoretical results.

Viremia associated with fatal outcomes in ferrets infected with avian H5N1 influenza virus.

Directory of Open Access Journals (Sweden)

Xue Wang

Full Text Available Avian H5N1 influenza viruses cause severe disease and high mortality in infected humans. However, tissue tropism and underlying pathogenesis of H5N1 virus infection in humans needs further investigation. The objective of this work was to study viremia, tissue tropism and disease pathogenesis of H5N1 virus infection in the susceptible ferret animal model. To evaluate the relationship of morbidity and mortality with virus loads, we performed studies in ferrets infected with the H5N1 strain A/VN/1203/04 to assess clinical signs after infection and virus load in lung, brain, ileum, nasal turbinate, nasal wash, and blood. We observed that H5N1 infection in ferrets is characterized by high virus load in the brain and and low levels in the ileum using real-time PCR. In addition, viral RNA was frequently detected in blood one or two days before death and associated with symptoms of diarrhea. Our observations further substantiate pathogenicity of H5N1 and further indicate that viremia may be a bio-marker for fatal outcomes in H5N1 infection.

Effects of closing and reopening live poultry markets on the epidemic of human infection with avian influenza A virus

OpenAIRE

Lu, Jian; Liu, Wendong; Xia, Rui; Dai, Qigang; Bao, Changjun; Tang, Fenyang; Zhu, yefei; Wang, Qiao

2015-01-01

Abstract Live poultry markets (LPMs) are crucial places for human infection of influenza A (H7N9 virus). In Yangtze River Delta, LPMs were closed after the outbreak of human infection with avian influenza A (H7N9) virus, and then reopened when no case was found. Our purpose was to quantify the effect of LPMs? operations in this region on the transmission of influenza A (H7N9) virus. We obtained information about dates of symptom onset and locations for all human influenza A (H7N9) cases repor...

The innate immunity of guinea pigs against highly pathogenic avian influenza virus infection.

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Zhang, Kun; Xu, Wei Wei; Zhang, Zhaowei; Liu, Jing; Li, Jing; Sun, Lijuan; Sun, Weiyang; Jiao, Peirong; Sang, Xiaoyu; Ren, Zhiguang; Yu, Zhijun; Li, Yuanguo; Feng, Na; Wang, Tiecheng; Wang, Hualei; Yang, Songtao; Zhao, Yongkun; Zhang, Xuemei; Wilker, Peter R; Liu, WenJun; Liao, Ming; Chen, Hualan; Gao, Yuwei; Xia, Xianzhu

2017-05-02

H5N1 avian influenza viruses are a major pandemic concern. In contrast to the highly virulent phenotype of H5N1 in humans and many animal models, guinea pigs do not typically display signs of severe disease in response to H5N1 virus infection. Here, proteomic and transcriptional profiling were applied to identify host factors that account for the observed attenuation of A/Tiger/Harbin/01/2002 (H5N1) virulence in guinea pigs. RIG-I and numerous interferon stimulated genes were among host proteins with altered expression in guinea pig lungs during H5N1 infection. Overexpression of RIG-I or the RIG-I adaptor protein MAVS in guinea pig cell lines inhibited H5N1 replication. Endogenous GBP-1 expression was required for RIG-I mediated inhibition of viral replication upstream of the activity of MAVS. Furthermore, we show that guinea pig complement is involved in viral clearance, the regulation of inflammation, and cellular apoptosis during influenza virus infection of guinea pigs. This work uncovers features of the guinea pig innate immune response to influenza that may render guinea pigs resistant to highly pathogenic influenza viruses.

Pleomorphic Malignant Mesothelioma in a Broiler Breeder Infected with Avian Leucosis Virus Subgroup J.

Science.gov (United States)

Murakami, T; Sassa, Y

2018-04-01

Avian leucosis virus (ALV) is an oncogenic retrovirus that induces tumours including lymphoid leucosis and myeloid leucosis. Pleomorphic malignant mesothelioma and myelocytoma, which were thought to be induced by ALV subgroup J (ALV-J) infection, were identified in a 432-day-old broiler breeder. The bird showed no clinical signs; however, at necropsy examination there were multiple nodules in the alimentary tract. Microscopical analysis showed that these consisted of pleomorphic cells and myelocyte-like cells. Immunohistochemistry revealed that the pleomorphic cells were atypical and expressed cytokeratin, vimentin, c-kit, calretinin and ALV. The myelocyte-like cells were also positive for ALV. Retroviral type C particles were observed by electron microscopy. ALV-E and ALV-J nucleotide sequences were detected in DNA extracted from formalin-fixed and paraffin wax-embedded small intestinal tissue. Based on these results, the tumours were diagnosed as pleomorphic malignant mesothelioma and myelocytoma and were thought to have been induced by ALV-J infection. This is the first report of malignant mesothelioma associated with naturally acquired ALV-J infection. Copyright © 2018 Elsevier Ltd. All rights reserved.

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,

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

Avian metapneumovirus in the USA

Science.gov (United States)

In the United States of America (USA), avian metapneumovirus (aMPV) causes an upper respiratory tract infection in turkeys; no outbreaks have been reported in commercial chicken flocks. Typical clinical signs of the disease in turkey poults include coughing, sneezing, nasal discharge, tracheal rale...

Vertical transmission of avian leukosis virus subgroup J (ALV-J) from hens infected through artificial insemination with ALV-J infected semen.

Science.gov (United States)

Li, Yang; Cui, Shuai; Li, Weihua; Wang, Yixin; Cui, Zhizhong; Zhao, Peng; Chang, Shuang

2017-06-29

Avian leukosis virus (ALV) is one of the main causes of tumour development within the poultry industry in China. The subgroup J avian leukosis viruses (ALV-J), which induce erythroblastosis and myelocytomatosis, have the greatest pathogenicity and transmission ability within this class of viruses. ALV can be transmitted both horizontally and vertically; however, the effects of ALV infection in chickens-especially roosters-during the propagation, on future generations is not clear. Knowing the role of the cock in the transmission of ALV from generation to generation might contribute to the eradication programs for ALV. The results showed that two hens inseminated with ALV-J-positive semen developed temporary antibody responses to ALV-J at 4-5 weeks post insemination. The p27 antigen was detected in cloacal swabs of six hens, and in 3 of 26 egg albumens at 1-6 weeks after insemination. Moreover, no viremia was detected at 6 weeks after insemination even when virus isolation had been conducted six times at weekly intervals for each of the 12 females. However, ALV-J was isolated from 1 of their 34 progeny chicks at 1 week of age, and its gp85 had 98.4%-99.2% sequence identity with the gp85 of ALV-J isolated from semen samples of the six cocks. Our findings indicated that females that were late horizontally infected with ALV-J by artificial insemination might transmit the virus to progeny through eggs, which amounts to vertical transmission.

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

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.

Isolation of avian influenza virus in Texas.

Science.gov (United States)

Glass, S E; Naqi, S A; Grumbles, L C

1981-01-01

An avian influenza virus with surface antigens similar to those of fowl plague virus (Hav 1 Nav 2) was isolated in 1979 from 2 commercial turkey flocks in Central Texas. Two flocks in contact with these infected flocks developed clinical signs, gross lesions, and seroconversion but yielded no virus. This was the first recorded incidence of clinical avian influenza in Texas turkeys and only the second time that an agent with these surface antigens was isolated from turkeys in U.S.

Draft Genome Sequences of Three Escherichia coli Strains with Different In Vivo Pathogenicities in an Avian (Ascending) Infection Model of the Oviduct.

Science.gov (United States)

Olsen, Rikke Heidemann; Thøfner, Ida Cecilie Naundrup; Pors, Susanne Elisabeth; Christensen, Henrik; Bisgaard, Magne; Christensen, Jens Peter

2015-05-07

Here, we present three draft genome sequences of Escherichia coli strains that experimentally were proven to possess low (strain D2-2), intermediate (Chronic_salp), or high virulence (Cp6salp3) in an avian (ascending) infection model of the oviduct. Copyright © 2015 Olsen et al.

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. © 2013 Blackwell Publishing Ltd.

Orchitis in roosters with reduced fertility associated with avian infectious bronchitis virus and avian metapneumovirus infections.

Science.gov (United States)

Villarreal, L Y B; Brandão, P E; Chacón, J L; Assayag, M S; Maiorka, P C; Raffi, P; Saidenberg, A B S; Jones, R C; Ferreira, A J P

2007-12-01

The pathogenesis of infection involving both infectious bronchitis virus (IBV) and avian metapneumovirus (aMPV) causes reproductive damage in hens after viral replication in the epithelium of the oviduct, resulting in loss of cilia and degeneration and necrosis of the epithelial and glandular cells. Although IBV has been indicated as a possible cause of the formation of calcium stones in the epididymus of roosters, a definitive association has not been confirmed. This report describes the detection of IBV and aMPV in the testes of roosters from a Brazilian poultry broiler breeder's flock with epididymal stones and low fertility. Samples of testis, trachea, and lungs from breeder males aged 57 wk were positive for IBV by reverse transcriptase-polymerase chain reaction (RT-PCR), and virus isolation and testis samples were also positive for aMPV by RT-PCR. The inoculation of testis samples into embryonated chicken eggs via the allantoic cavity resulted in curled, hemorrhagic, and stunted embryos typical of IBV infection. The allantoic fluid was positive by RT-PCR aimed to amplify the region coding for the S1 subunit of the IBV S gene, but it was not positive for aMPV. Sequence analysis of the amplified fragment revealed a close relationship with European IBV genotype D274, previously unreported in Brazil. These results indicate that IBV and perhaps aMPV are likely to have played a role in the pathogenesis of the testicular disease described and should be regarded as factors that can influence male fertility disease in chickens.

No evidence that migratory geese disperse avian influenza viruses from breeding to wintering ground.

Directory of Open Access Journals (Sweden)

Shenglai Yin

Full Text Available Low pathogenic avian influenza virus can mutate to a highly pathogenic strain that causes severe clinical signs in birds and humans. Migratory waterfowl, especially ducks, are considered the main hosts of low pathogenic avian influenza virus, but the role of geese in dispersing the virus over long-distances is still unclear. We collected throat and cloaca samples from three goose species, Bean goose (Anser fabalis, Barnacle goose (Branta leucopsis and Greater white-fronted goose (Anser albifrons, from their breeding grounds, spring stopover sites, and wintering grounds. We tested if the geese were infected with low pathogenic avian influenza virus outside of their wintering grounds, and analysed the spatial and temporal patterns of infection prevalence on their wintering grounds. Our results show that geese were not infected before their arrival on wintering grounds. Barnacle geese and Greater white-fronted geese had low prevalence of infection just after their arrival on wintering grounds in the Netherlands, but the prevalence increased in successive months, and peaked after December. This suggests that migratory geese are exposed to the virus after their arrival on wintering grounds, indicating that migratory geese might not disperse low pathogenic avian influenza virus during autumn migration.

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

Memory T cells established by seasonal human influenza A infection cross-react with avian influenza A (H5N1) in healthy individuals

NARCIS (Netherlands)

Lee, Laurel Yong-Hwa; Anh, Ha Do Lien; Simmons, Cameron; de Jong, Menno D.; Chau, Nguyen Van Vinh; Schumacher, Reto; Peng, Yan Chun; McMichael, Andrew J.; Farrar, Jeremy J.; Smith, Geoffrey L.; Townsend, Alain R. M.; Askonas, Brigitte A.; Rowland-Jones, Sarah; Dong, Tao

2008-01-01

The threat of avian influenza A (H5N1) infection in humans remains a global health concern. Current influenza vaccines stimulate antibody responses against the surface glycoproteins but are ineffective against strains that have undergone significant antigenic variation. An alternative approach is to

Detection of H5N1 high-pathogenicity avian influenza virus in meat and tracheal samples from experimentally infected chickens.

Science.gov (United States)

Das, Amaresh; Spackman, Erica; Thomas, Colleen; Swayne, David E; Suarez, David L

2008-03-01

The Asian H5N1 highly pathogenic avian influenza (HPAI) virus causes a systemic disease with high mortality of poultry and is potentially zoonotic. In both chickens and ducks, the virus has been demonstrated to replicate in both cardiac and skeletal muscle cells. Experimentally, H5N1 HPAI virus has been transmitted to chickens through the consumption of raw infected meat. In this study, we investigated virus replication in cardiac and skeletal muscle and in the trachea of chickens after experimental intranasal inoculation with the H5N1 HPAI virus. The virus was detected in tissues by real-time reverse transcription-polymerase chain reaction (RRT-PCR) and virus isolation, and in the trachea by RRT-PCR and a commercial avian influenza (AI) viral antigen detection test. A modified RNA extraction protocol was developed for rapid detection of the virus in tissues by RRT-PCR. The H5N1 HPAI virus was sporadically detected in meat and the tracheas of infected birds without any clinical sign of disease as early as 6 hr postinfection (PI), and was detected in all samples tested at 24 hr PI and later. No differences in sensitivity were seen between virus isolation and RRT-PCR in meat samples. The AI viral antigen detection test on tracheal swabs was a useful method for identifying infected chickens when they were sick or dead, but was less sensitive in detecting infected birds when they were preclinical. This study provides data indicating that preslaughter tracheal swab testing can identify birds infected with HPAI among the daily mortality and prevent infected flocks from being sent to processing plants. In addition, the modified RNA extraction and RRT-PCR test on meat samples provide a rapid and sensitive method of identifying HPAI virus in illegal contraband or domestic meat samples.

Avian influenza virus (H5N1): a threat to human health

NARCIS (Netherlands)

Peiris, J. S. Malik; de Jong, Menno D.; Guan, Yi

2007-01-01

Pandemic influenza virus has its origins in avian influenza viruses. The highly pathogenic avian influenza virus subtype H5N1 is already panzootic in poultry, with attendant economic consequences. It continues to cross species barriers to infect humans and other mammals, often with fatal outcomes.

Reverse genetics of avian metapneumoviruses

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An overview of avian metapneumovirus (aMPV) infection in turkeys and development of a reverse genetics system for aMPV subgroup C (aMPV-C) virus will be presented. By using reverse genetics technology, we generated recombinant aMPV-C viruses containing a different length of glycoprotein (G) gene or...

Isolation strategy of a two-strain avian influenza model using optimal control

Science.gov (United States)

Mardlijah, Ariani, Tika Desi; Asfihani, Tahiyatul

2017-08-01

Avian influenza has killed many victims of both birds and humans. Most cases of avian influenza infection in humans have resulted transmission from poultry to humans. To prevent or minimize the patients of avian influenza can be done by pharmaceutical and non-pharmaceutical measures such as the use of masks, isolation, etc. We will be analyzed two strains of avian influenza models that focus on treatment of symptoms with insulation, then investigate the stability of the equilibrium point by using Routh-Hurwitz criteria. We also used optimal control to reduce the number of humans infected by making the isolation level as the control then proceeds optimal control will be simulated. The completion of optimal control used in this study is the Pontryagin Minimum Principle and for simulation we are using Runge Kutta method. The results obtained showed that the application of two control is more optimal compared to apply one control only.

Avian and human influenza virus compatible sialic acid receptors in little brown bats.

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Chothe, Shubhada K; Bhushan, Gitanjali; Nissly, Ruth H; Yeh, Yin-Ting; Brown, Justin; Turner, Gregory; Fisher, Jenny; Sewall, Brent J; Reeder, DeeAnn M; Terrones, Mauricio; Jayarao, Bhushan M; Kuchipudi, Suresh V

2017-04-06

Influenza A viruses (IAVs) continue to threaten animal and human health globally. Bats are asymptomatic reservoirs for many zoonotic viruses. Recent reports of two novel IAVs in fruit bats and serological evidence of avian influenza virus (AIV) H9 infection in frugivorous bats raise questions about the role of bats in IAV epidemiology. IAVs bind to sialic acid (SA) receptors on host cells, and it is widely believed that hosts expressing both SA α2,3-Gal and SA α2,6-Gal receptors could facilitate genetic reassortment of avian and human IAVs. We found abundant co-expression of both avian (SA α2,3-Gal) and human (SA α2,6-Gal) type SA receptors in little brown bats (LBBs) that were compatible with avian and human IAV binding. This first ever study of IAV receptors in a bat species suggest that LBBs, a widely-distributed bat species in North America, could potentially be co-infected with avian and human IAVs, facilitating the emergence of zoonotic strains.

[Clinical aspects of human infection by the avian influenza virus].

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Goubau, P

2009-01-01

The species barrier is not perfect for Influenza A and numerous transmissions of the virus from pigs or poultry to humans have been described these years. Appearing in 1997 and becoming epidemic in 2003, influenza A/H5N1 provoked many deadly enzootics in poultry batteries (highly pathogenic avian influenza of HPAI). Starting in Asia, many countries throughout Africa and Europe were affected. Sporadic human cases were described in direct contact with diseased chicken or other poultry. Half of the cases are lethal, but human to human transmission occurs with difficulty. From January 2003 to August 11th 2009, 438 cases were declared worldwide with 262 deaths. Many countries declared cases, but recently most cases occurred in Egypt. Measures in hospital were taken which were copied from the measures for SARS (Severe Acute Respiratory Syndrome), but these were probably excessive in this case, considering the low rate of secondary cases with A/H5N1. In many human infections, signs of severe respiratory distress develop and multi organ failure. It was feared that this deadly virus could become easily transmitted between humans, leading to a new pandemic. This was not the case up to now. The strong pathogenicity of the virus is still not completely explained, but the deep location of infection in the lungs and the deregulation of cytokine production by the target cells, particularly macrophages, may be part of the explanation.

Transmission and immunopathology of the avian influenza virus A/Anhui/1/2013 (H7N9) human isolate in three commonly commercialized avian species.

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Vidaña, B; Dolz, R; Busquets, N; Ramis, A; Sánchez, R; Rivas, R; Valle, R; Cordón, I; Solanes, D; Martínez, J; Majó, N

2018-05-01

H7N9 virus infection is a global concern, given that it can cause severe infection and mortality in humans. However, the understanding of H7N9 epidemiology, animal reservoir species and zoonotic risk remains limited. This work evaluates the pathogenicity, transmissibility and local innate immune response of three avian species harbouring different respiratory distribution of α2,6 and α2,3 SA receptors. Muscovy ducks, European quails and SPF chickens were intranasally inoculated with 10 5 embryo infectious dose (EID) 50 of the human H7N9 (A/Anhui/1/2013) influenza isolate. None of the avian species showed clinical signs or macroscopic lesions, and only mild microscopic lesions were observed in the upper respiratory tract of quail and chickens. Quail presented more severe histopathologic lesions and avian influenza virus (AIV) positivity by immunohistochemistry (IHC), which correlated with higher IL-6 responses. In contrast, Muscovy ducks were resistant to disease and presented higher IFNα and TLR7 response. In all species, viral shedding was higher in the respiratory than in the digestive tract. Higher viral shedding was observed in quail, followed by chicken and ducks, which presented similar viral titres. Efficient transmission was observed in all contact quail and half of the Muscovy ducks, while no transmission was observed between chicken. All avian species showed viral shedding in drinking water throughout infection. © 2017 Blackwell Verlag GmbH.

Emergence of the virulence-associated PB2 E627K substitution in a fatal human case of highly pathogenic avian influenza virus A(H7N7) infection as determined by Illumina ultra-deep sequencing

NARCIS (Netherlands)

Jonges, Marcel; Welkers, Matthijs R. A.; Jeeninga, Rienk E.; Meijer, Adam; Schneeberger, Peter; Fouchier, Ron A. M.; de Jong, Menno D.; Koopmans, Marion

2014-01-01

Avian influenza viruses are capable of crossing the species barrier and infecting humans. Although evidence of human-to-human transmission of avian influenza viruses to date is limited, evolution of variants toward more-efficient human-to-human transmission could result in a new influenza virus

Human infection with a highly pathogenic avian influenza A (H5N6) virus in Yunnan province, China.

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Xu, Wen; Li, Hong; Jiang, Li

2016-01-01

Highly pathogenic avian influenza A H5N6 virus has caused four human infections in China. This study reports the preliminary findings of the first known human case of H5N6 in Yunnan province. The patient initially developed symptoms of sore throat and coughing on 27 January 2015. The disease rapidly progressed to severe pneumonia, multiple organ dysfunctions and acute respiratory distress syndrome and the patient died on 6 February. Virological analysis determined that the virus belonged to H5 clade 2.3.4.4 and it has obtained partial ability for mammalian adaptation and amantadine resistance. Environmental investigation found H5 in 63% of the samples including poultry faeces, tissues, cage surface swabs and sewage from local live poultry markets by real-time RT-PCR. These findings suggest that the expanding and enhancing of surveillance in both avian and humans are necessary to monitor the evolution of H5 influenza virus and to facilitate early detection of suspected cases.

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

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Sandford, Erin E; Orr, Megan; Balfanz, Emma; Bowerman, Nate; Li, Xianyao; Zhou, Huaijun; Johnson, Timothy J; Kariyawasam, Subhashinie; Liu, Peng; Nolan, Lisa K; Lamont, Susan J

2011-09-27

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. 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. 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, but also the degree of pathology associated with that

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

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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

Investigation of avian influenza infection in wild birds in Ismailia and Damietta cities, Egypt

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Fadel, Hanaa Mohamed; Afifi, Rabab

2017-01-01

Aim: This study was carried out to monitor avian influenza (AI) infection in wild birds in Egypt. Materials and Methods: A total of 135 wild birds were examined for the presence of H5, H7, and H9 hemagglutination inhibition antibodies. Organs and swab samples of 75 birds were screened by multiplex real-time reverse transcriptase-polymerase chain reaction (RRT-PCR) to detect AI subtypes H5, H7, and H9 matrix genes. Results: The highest seropositive result was recorded in cattle egrets (90.9%) followed by crows (88.6%), semi-captive pigeons (44.8%), and moorhens (39.1%). In cattle egrets, semi-captive pigeons and moorhens, H5 antibodies predominated. In crows, H9 antibodies predominated. Multiple infections with two or three virus subtypes were highest in crows (6/39, 15.4%) followed by cattle egrets (3/30, 10%) and moorhens’ (1/9, 11.1%) positive samples. Multiplex RRT-PCR results revealed two positive samples in cattle egrets and moorhens. Conclusion: The results indicated high seropositive rates against AI virus subtypes H5 and H9 in the examined wild birds. Multiple infections with more than one AI virus (AIV) subtypes were detected in some birds. This requires a collaboration of efforts to monitor AIV infection in wild birds and implement suitable early intervention measures. PMID:28717324

[Exposure to avian influenza virus and the infection status of virus among people breeding or butchering ducks in the suburb of Beijing].

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Ma, Chun-na; Yang, Peng; Zhang, Yi; Li, Hai-yue; Zhang, Li; Li, Li-li; Li, Chao; Yang, Yu-song; Chen, He; Zhang, Song-jian; Liu, Xiu-jun; Wang, Quan-yi

2012-04-01

To understand the exposure and the infection status of virus among people engaging in breeding or butchering ducks in the suburb of Beijing. People from six districts (Daxing, Fangshan, Huairou, Miyun, Shunyi, Tongzhou) who engaged in breeding or butchering ducks were studied and the status of infecting avian influenza virus was obtained by testing antibody level in serum. Information on demographic characteristics, status of regular exposure and exposure to sick or dead poultry were collected through a self-designed questionnaire. 1741 people were involved in this study in which 313 (18.0%) were workers in duck-breeding enterprise, 562 (32.3%) were workers in duck slaughterhouse, 261 (15.0%) farmers were in individual small-scale duck farms, 605 (34.7%) were farmers raising duck in backyard. Among farmers raising duck in backyard, the percentage of people whose ducks ever contacted with wild birds was higher than the other three groups (66.8%) (Ppoultry, higher proportion was found among those who had ever closely contacted sick or dead poultry commercial duck raisers (36.1%) and individuals who raise large amount of ducks (36.0%). 70.8% of the individual duck raisers had never taken any protective measures when closely contacting the sick or dead poultry. Among 1741 samples, 0 were positive to avian influenza virus H5 and H7 subtypes. 12 were positive to H9 subtype (positive rate was 0.7%), in which 10 were farmers raising ducks in backyard (the positive rate of 1.7%). Differences between H9 subtype antibody positive rates difference in 4 population groups were statistically significant (χ2=13.699, Ppoultry. Our findings suggested that some intervention measures should be taken to reduce the risk of avian influenza infection.

Virus interference between H7N2 low pathogenic avian influenza virus and lentogenic Newcastle disease virus in experimental co-infections in chickens and turkeys

OpenAIRE

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

2014-01-01

International audience; Low pathogenicity avian influenza virus (LPAIV) and lentogenic Newcastle disease virus (l NDV) are commonly reported causes of respiratory disease in poultry worldwide with similar clinical and pathobiological presentation. Co-infections do occur but are not easily detected, and the impact of co-infections on pathobiology is unknown. In this study chickens and turkeys were infected with a l NDV vaccine strain (LaSota) and a H7N2 LPAIV (A/turkey/VA/SEP-67/2002) simultan...

Diversity, abundance, and host relationships of avian malaria and related haemosporidians in New Mexico pine forests

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Rosario A. Marroquin-Flores

2017-08-01

Full Text Available Avian malaria and related haemosporidian parasites (genera Haemoproteus, Plasmodium, and Leucocytozoon affect bird demography, species range limits, and community structure, yet they remain unsurveyed in most bird communities and populations. We conducted a community-level survey of these vector-transmitted parasites in New Mexico, USA, to describe their diversity, abundance, and host associations. We focused on the breeding-bird community in the transition zone between piñon-juniper woodland and ponderosa pine forests (elevational range: 2,150–2,460 m. We screened 186 birds representing 49 species using both standard PCR and microscopy techniques to detect infections of all three avian haemosporidian genera. We detected infections in 68 out of 186 birds (36.6%, the highest proportion of which were infected with Haemoproteus (20.9%, followed by Leucocytozoon (13.4%, then Plasmodium (8.0%. We sequenced mtDNA for 77 infections representing 43 haplotypes (25 Haemoproteus, 12 Leucocytozoon, 6 Plasmodium. When compared to all previously known haplotypes in the MalAvi and GenBank databases, 63% (27 of the haplotypes we recovered were novel. We found evidence for host specificity at the avian clade and species level, but this specificity was variable among parasite genera, in that Haemoproteus and Leucocytozoon were each restricted to three avian groups (out of six, while Plasmodium occurred in all groups except non-passerines. We found striking variation in infection rate among host species, with nearly universal infection among vireos and no infection among nuthatches. Using rarefaction and extrapolation, we estimated the total avian haemosporidian diversity to be 70 haplotypes (95% CI [43–98]; thus, we may have already sampled ∼60% of the diversity of avian haemosporidians in New Mexico pine forests. It is possible that future studies will find higher diversity in microhabitats or host species that are under-sampled or unsampled in the

Cross-Species Infectivity of H3N8 Influenza Virus in an Experimental Infection in Swine.

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Solórzano, Alicia; Foni, Emanuela; Córdoba, Lorena; Baratelli, Massimiliano; Razzuoli, Elisabetta; Bilato, Dania; Martín del Burgo, María Ángeles; Perlin, David S; Martínez, Jorge; Martínez-Orellana, Pamela; Fraile, Lorenzo; Chiapponi, Chiara; Amadori, Massimo; del Real, Gustavo; Montoya, María

2015-11-01

Avian influenza A viruses have gained increasing attention due to their ability to cross the species barrier and cause severe disease in humans and other mammal species as pigs. H3 and particularly H3N8 viruses, are highly adaptive since they are found in multiple avian and mammal hosts. H3N8 viruses have not been isolated yet from humans; however, a recent report showed that equine influenza A viruses (IAVs) can be isolated from pigs, although an established infection has not been observed thus far in this host. To gain insight into the possibility of H3N8 avian IAVs to cross the species barrier into pigs, in vitro experiments and an experimental infection in pigs with four H3N8 viruses from different origins (equine, canine, avian, and seal) were performed. As a positive control, an H3N2 swine influenza virus A was used. Although equine and canine viruses hardly replicated in the respiratory systems of pigs, avian and seal viruses replicated substantially and caused detectable lesions in inoculated pigs without previous adaptation. Interestingly, antibodies against hemagglutinin could not be detected after infection by hemagglutination inhibition (HAI) test with avian and seal viruses. This phenomenon was observed not only in pigs but also in mice immunized with the same virus strains. Our data indicated that H3N8 IAVs from wild aquatic birds have the potential to cross the species barrier and establish successful infections in pigs that might spread unnoticed using the HAI test as diagnostic tool. Although natural infection of humans with an avian H3N8 influenza A virus has not yet been reported, this influenza A virus subtype has already crossed the species barrier. Therefore, we have examined the potential of H3N8 from canine, equine, avian, and seal origin to productively infect pigs. Our results demonstrated that avian and seal viruses replicated substantially and caused detectable lesions in inoculated pigs without previous adaptation. Surprisingly, we

Knock-Down of Endogenous Bornavirus-Like Nucleoprotein 1 Inhibits Cell Growth and Induces Apoptosis in Human Oligodendroglia Cells

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Peng He

2016-03-01

Full Text Available Endogenous bornavirus-like nucleoprotein elements (EBLNs have been discovered in the genomes of various animals including humans, whose functions have been seldom studied. To explore the biological functions of human EBLNs, we constructed a lentiviral vector expressing a short-hairpin RNA against human EBLN1, which successfully inhibited EBLN1 expression by above 80% in infected human oligodendroglia cells (OL cells. We found that EBLN1 silencing suppressed cell proliferation, induced G2/M phase arrest, and promoted apoptosis in OL cells. Gene expression profiling demonstrated that 1067 genes were up-regulated, and 2004 were down-regulated after EBLN1 silencing. The top 10 most upregulated genes were PI3, RND3, BLZF1, SOD2, EPGN, SBSN, INSIG1, OSMR, CREB3L2, and MSMO1, and the top 10 most-downregulated genes were KRTAP2-4, FLRT2, DIDO1, FAT4, ESCO2, ZNF804A, SUV420H1, ZC3H4, YAE1D1, and NCOA5. Pathway analysis revealed that these differentially expressed genes were mainly involved in pathways related to the cell cycle, the mitogen-activated protein kinase pathway, p53 signaling, and apoptosis. The gene expression profiles were validated by using quantitative reverse transcription polymerase chain reaction (RT-PCR for detecting these 20 most-changed genes. Three genes closely related to glioma, RND3, OSMR, and CREB3L2, were significantly upregulated and might be the key factors in EBLN1 regulating the proliferation and apoptosis of OL cells. This study provides evidence that EBLN1 plays a key role in regulating cell life and death, thereby opening several avenues of investigation regarding EBLN1 in the future.

Experimental infection of clade 1.1.2 (H5N1), clade 2.3.2.1c (H5N1) and clade 2.3.4.4 (H5N6) highly pathogenic avian influenza viruses in dogs.

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Lyoo, K S; Na, W; Phan, L V; Yoon, S W; Yeom, M; Song, D; Jeong, D G

2017-12-01

Since the emergence of highly pathogenic avian influenza (HPAI) H5N1 in Asia, the haemagglutinin (HA) gene of this virus lineage has continued to evolve in avian populations, and H5N1 lineage viruses now circulate concurrently worldwide. Dogs may act as an intermediate host, increasing the potential for zoonotic transmission of influenza viruses. Virus transmission and pathologic changes in HPAI clade 1.1.2 (H5N1)-, 2.3.2.1c (H5N1)- and 2.3.4.4 (H5N6)-infected dogs were investigated. Mild respiratory signs and antibody response were shown in dogs intranasally infected with the viruses. Lung histopathology showed lesions that were associated with moderate interstitial pneumonia in the infected dogs. In this study, HPAI H5N6 virus replication in dogs was demonstrated for the first time. Dogs have been suspected as a "mixing vessel" for reassortments between avian and human influenza viruses to occur. The replication of these three subtypes of the H5 lineage of HPAI viruses in dogs suggests that dogs could serve as intermediate hosts for avian-human influenza virus reassortment if they are also co-infected with human influenza viruses. © 2017 Blackwell Verlag GmbH.

A comparative evaluation of feathers, oropharyngeal swabs, and cloacal swabs for the detection of H5N1 highly pathogenic avian influenza virus infection in experimentally infected chickens and ducks.

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Nuradji, Harimurti; Bingham, John; Lowther, Sue; Wibawa, Hendra; Colling, Axel; Long, Ngo Thanh; Meers, Joanne

2015-11-01

Oropharyngeal and cloacal swabs have been widely used for the detection of H5N1 highly pathogenic avian Influenza A virus (HPAI virus) in birds. Previous studies have shown that the feather calamus is a site of H5N1 virus replication and therefore has potential for diagnosis of avian influenza. However, studies characterizing the value of feathers for this purpose are not available, to our knowledge; herein we present a study investigating feathers for detection of H5N1 virus. Ducks and chickens were experimentally infected with H5N1 HPAI virus belonging to 1 of 3 clades (Indonesian clades 2.1.1 and 2.1.3, Vietnamese clade 1). Different types of feathers and oropharyngeal and cloacal swab samples were compared by virus isolation. In chickens, virus was detected from all sample types: oral and cloacal swabs, and immature pectorosternal, flight, and tail feathers. During clinical disease, the viral titers were higher in feathers than swabs. In ducks, the proportion of virus-positive samples was variable depending on viral strain and time from challenge; cloacal swabs and mature pectorosternal feathers were clearly inferior to oral swabs and immature pectorosternal, tail, and flight feathers. In ducks infected with Indonesian strains, in which most birds did not develop clinical signs, all sampling methods gave intermittent positive results; 3-23% of immature pectorosternal feathers were positive during the acute infection period; oropharyngeal swabs had slightly higher positivity during early infection, while feathers performed better during late infection. Our results indicate that immature feathers are an alternative sample for the diagnosis of HPAI in chickens and ducks. © 2015 The Author(s).

Studies on avian malaria in vectors and hosts of encephalitis in Kern County, California. I. Infections in avian hosts

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Herman, C.M.; Reeves, W.C.; McClure, H.E.; French, E.M.; Hammon, W.M.

1954-01-01

ranged from 64 to 100 per cent in the house finch and 17 to 68 per cent in the English sparrow in different areas and years. Marked differences were found in the prevalence rates in different summer months, years and areas. It is believed these differences reflect variation in a number of environmental factors. This study indicates the extensive distribution of Plasmodium infection in a wide range of wild avian hosts. The observations are of possible importance in epidemiological studies of other arthropod-borne diseases such as the viral encephalitides for which these birds serve as hosts.

Characterisation and Identification of Avian Influenza Virus (AI

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Dyah Ayu Hewajuli

2008-06-01

Full Text Available Avian Influenza is caused by Influenza A virus which is a member of Orthomyxoviridae family. Influenza A virus is enveloped single stranded RNA with eight-segmented, negative polarity and filament or oval form, 50 – 120 by 200 – 300 nm diameters. Influenza A viruses have been found to infect birds, human, pig, horse and sometimes in the other mammalian such as seal and whale. The viruses are divided into different subtypes based on the antigenic protein which covers the virus surface i.e. Haemaglutinin (HA and Neuraminidase (NA. In addition, the nomenclature of subtype virus is based on HA and NA i.e HxNx, for example H5N1, H9N2 and the others. According to pathogenic, it could be divided into two distinct groups, they are Highly Pathogenic Avian Influenza (HPAI and Low Pathogenic Avian Influenza (LPAI. The Avian Influenza viruses have been continuously occurred and spread out in some continents such us America, Europe, Africa and Asian countries. The outbreak of Avian Influenza caused high mortality on birds and it has been reported that in human case Avian Influenza subtype H5N1 virus has caused several deaths. To anticipate this condition, an effort to prevent the transmission of Avian Influenza is needed. These strategic attempts include biosecurity, depopulation, vaccination, control of virus movement, monitoring and evaluation. Laboratory diagnostic plays an important role for successful prevention, control and eradication programs of Avian Influenza. Recently, there are two diagnostic methods for Avian Influenza. They are conventional (virological diagnosis and molecular methods. The conventional method is usually used for initial diagnostic of Avian Influenza. The conventional method takes more time and more costly, whereas the molecular method is more effective than conventional method. Based on the available diagnostic technique, basically diagnostic of Avian Influenza is done by serology test, isolation and identification as well

Public Health and Epidemiological Considerations For Avian Influenza Risk Mapping and Risk Assessment

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Joseph P. Dudley

2008-12-01

Full Text Available Avian influenza viruses are now widely recognized as important threats to agricultural biosecurity and public health, and as the potential source for pandemic human influenza viruses. Human infections with avian influenza viruses have been reported from Asia (H5N1, H5N2, H9N2, Africa (H5N1, H10N7, Europe (H7N7, H7N3, H7N2, and North America (H7N3, H7N2, H11N9. Direct and indirect public health risks from avian influenzas are not restricted to the highly pathogenic H5N1 "bird flu" virus, and include low pathogenic as well as high pathogenic strains of other avian influenza virus subtypes, e.g., H1N1, H7N2, H7N3, H7N7, and H9N2. Research has shown that the 1918 Spanish Flu pandemic was caused by an H1N1 influenza virus of avian origins, and during the past decade, fatal human disease and human-to-human transmission has been confirmed among persons infected with H5N1 and H7N7 avian influenza viruses. Our ability to accurately assess and map the potential economic and public health risks associated with avian influenza outbreaks is currently constrained by uncertainties regarding key aspects of the ecology and epidemiology of avian influenza viruses in birds and humans, and the mechanisms by which highly pathogenic avian influenza viruses are transmitted between and among wild birds, domestic poultry, mammals, and humans. Key factors needing further investigation from a risk management perspective include identification of the driving forces behind the emergence and persistence of highly pathogenic avian influenza viruses within poultry populations, and a comprehensive understanding of the mechanisms regulating transmission of highly pathogenic avian influenza viruses between industrial poultry farms and backyard poultry flocks. More information is needed regarding the extent to which migratory bird populations to contribute to the transnational and transcontinental spread of highly pathogenic avian influenza viruses, and the potential for wild bird

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.

A cross-sectional study of avian influenza in one district of Guangzhou, 2013.

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Haiming Zhang

Full Text Available Since Feb, 2013, more than 100 human beings had been infected with novel H7N9 avian influenza virus. As of May 2013, several H7N9 viruses had been found in retail live bird markets (LBMs in Guangdong province of southern China where several human cases were confirmed later. However, the real avian influenza virus infection status especially H7N9 in Guangzhou remains unclear. Therefore, a cross-sectional study of avian influenza in commercial poultry farms, the wholesale LBM and retail LBMs in one district of Guangzhou was conducted from October to November, 2013. A total of 1505 cloacal and environmental samples from 52 commercial poultry farms, 1 wholesale LBM and 18 retail LBMs were collected and detected using real-time RT-PCR for type A, H7, H7N9 and H9 subtype avian influenza virus, respectively. Of all the flocks randomly sampled, 6 farms, 12 vendors of the wholesale LBM and 18 retail LBMs were type A avian influenza virus positive with 0, 3 and 11 positive for H9, respectively. The pooled prevalence and individual prevalence of type A avian influenza virus were 33.9% and 7.9% which for H9 subtype was 7.6% and 1.6%, respectively. None was H7 and H7N9 subtype virus positive. Different prevalence and prevalence ratio were found in different poultry species with partridges having the highest prevalence for both type A and H9 subtype avian influenza virus. Our results suggest that LBM may have a higher risk for sustaining and transmission of avian influenza virus than commercial poultry farms. The present study also indicates that different species may play different roles in the evolution and transmission of avian influenza virus. Therefore, risk-based surveillance and management measures should be conducted in future in this area.

Experimental infection of macaques with a wild water bird-derived highly pathogenic avian influenza virus (H5N1.

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Tomoko Fujiyuki

Full Text Available Highly pathogenic avian influenza virus (HPAIV continues to threaten human health. Non-human primate infection models of human influenza are desired. To establish an animal infection model with more natural transmission and to determine the pathogenicity of HPAIV isolated from a wild water bird in primates, we administered a Japanese isolate of HPAIV (A/whooper swan/Hokkaido/1/2008, H5N1 clade 2.3.2.1 to rhesus and cynomolgus monkeys, in droplet form, via the intratracheal route. Infection of the lower and upper respiratory tracts and viral shedding were observed in both macaques. Inoculation of rhesus monkeys with higher doses of the isolate resulted in stronger clinical symptoms of influenza. Our results demonstrate that HPAIV isolated from a water bird in Japan is pathogenic in monkeys by experimental inoculation, and provide a new method for HPAIV infection of non-human primate hosts, a good animal model for investigation of HPAIV pathogenicity.

Transmission of Avian Influenza Virus (H3N2) to Dogs

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Song, Daesub; Kang, Bokyu; Lee, Chulseung; Jung, Kwonil; Ha, Gunwoo; Kang, Dongseok; Park, Seongjun; Park, Bongkyun; Oh, Jinsik

2008-01-01

In South Korea, where avian influenza virus subtypes H3N2, H5N1, H6N1, and H9N2 circulate or have been detected, 3 genetically similar canine influenza virus (H3N2) strains of avian origin (A/canine/Korea/01/2007, A/canine/Korea/02/2007, and A/canine/Korea/03/2007) were isolated from dogs exhibiting severe respiratory disease. To determine whether the novel canine influenza virus of avian origin was transmitted among dogs, we experimentally infected beagles with this influenza virus (H3N2) is...

USGS highly pathogenic avian influenza research strategy

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Harris, M. Camille; Miles, A. Keith; Pearce, John M.; Prosser, Diann J.; Sleeman, Jonathan M.; Whalen, Mary E.

2015-09-09

Avian influenza viruses are naturally occurring in wild birds such as ducks, geese, swans, and gulls. These viruses generally do not cause illness in wild birds, however, when spread to poultry they can be highly pathogenic and cause illness and death in backyard and commercial farms. Outbreaks may cause devastating agricultural economic losses and some viral strains have the potential to infect people directly. Furthermore, the combination of avian influenza viruses with mammalian viruses can result in strains with the ability to transmit from person to person, possibly leading to viruses with pandemic potential. All known pandemic influenza viruses have had some genetic material of avian origin. Since 1996, a strain of highly pathogenic avian influenza (HPAI) virus, H5N1, has caused infection in wild birds, losses to poultry farms in Eurasia and North Africa, and led to the deaths of several hundred people. Spread of the H5N1 virus and other influenza strains from China was likely facilitated by migratory birds. In December 2014, HPAI was detected in poultry in Canada and migratory birds in the United States. Since then, HPAI viruses have spread to large parts of the United States and will likely continue to spread through migratory bird flyways and other mechanisms throughout North America. In the United States, HPAI viruses have severely affected the poultry industry with millions of domestic birds dead or culled. These strains of HPAI are not known to cause disease in humans; however, the Centers for Disease Control and Prevention (CDC) advise caution when in close contact with infected birds. Experts agree that HPAI strains currently circulating in wild birds of North America will likely persist for the next few years. This unprecedented situation presents risks to the poultry industry, natural resource management, and potentially human health. Scientific knowledge and decision support tools are urgently needed to understand factors affecting the persistence

Influenza A virus infections in marine mammals and terrestrial carnivores.

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Harder, Timm C; Siebert, Ursula; Wohlsein, Peter; Vahlenkamp, Thomas

2013-01-01

Influenza A viruses (IAV), members of the Orthomyxoviridae, cover a wide host spectrum comprising a plethora of avian and, in comparison, a few mammalian species. The viral reservoir and gene pool are kept in metapopulations of aquatic wild birds. The mammalian-adapted IAVs originally arose by transspecies transmission from avian sources. In swine, horse and man, species-adapted IAV lineages circulate independently of the avian reservoir and cause predominantly respiratory disease of highly variable severity. Sporadic outbreaks of IAV infections associated with pneumonic clinical signs have repeatedly occurred in marine mammals (harbour seals [Phoca vitulina]) off the New England coast of the U.S.A. due to episodic transmission of avian IAV. However, no indigenous marine mammal IAV lineages are described. In contrast to marine mammals, avian- and equine-derived IAVs have formed stable circulating lineages in terrestrial carnivores: IAVs of subtype H3N2 and H3N8 are found in canine populations in South Korea, China, and the U.S.A. Experimental infections revealed that dogs and cats can be infected with an even wider range of avian IAVs. Cats, in particular, also proved susceptible to native infection with human pandemic H1N1 viruses and, according to serological data, may be vulnerable to infection with further human-adapted IAVs. Ferrets are susceptible to a variety of avian and mammalian IAVs and are an established animal model of human IAV infection. Thus, a potential role of pet cats, dogs and ferrets as mediators of avian-derived viruses to the human population does exist. A closer observation for influenza virus infections and transmissions at this animal-human interface is indicated.

Clostridium difficile Infection in Production Animals and Avian Species: A Review.

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Moono, Peter; Foster, Niki F; Hampson, David J; Knight, Daniel R; Bloomfield, Lauren E; Riley, Thomas V

2016-12-01

Clostridium difficile is the leading cause of antibiotic-associated diarrhea and colitis in hospitalized humans. Recently, C. difficile infection (CDI) has been increasingly recognized as a cause of neonatal enteritis in food animals such as pigs, resulting in stunted growth, delays in weaning, and mortality, as well as colitis in large birds such as ostriches. C. difficile is a strictly anaerobic spore-forming bacterium, which produces two toxins A (TcdA) and B (TcdB) as its main virulence factors. The majority of strains isolated from animals produce an additional binary toxin (C. difficile transferase) that is associated with increased virulence. C. difficile is ubiquitous in the environment and has a wide host range. This review summarizes the epidemiology, clinical presentations, risk factors, and laboratory diagnosis of CDI in animals. Increased awareness by veterinarians and animal owners of the significance of clinical disease caused by C. difficile in livestock and avians is needed. Finally, this review provides an overview on methods for controlling environmental contamination and potential therapeutics available.

Avian and human metapneumovirus.

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Broor, Shobha; Bharaj, Preeti

2007-04-01

Pneumovirus infection remains a significant problem for both human and veterinary medicine. Both avian pneumovirus (aMPV, Turkey rhinotracheitis virus) and human metapneumovirus (hMPV) are pathogens of birds and humans, which are associated with respiratory tract infections. Based on their different genomic organization and low level of nucleotide (nt) and amino acid (aa) identity with paramyxoviruses in the genus Pneumovirus, aMPV and hMPV have been classified into a new genus referred to as Metapneumovirus. The advancement of our understanding of pneumovirus biology and pathogenesis of pneumovirus disease in specific natural hosts can provide us with strategies for vaccine formulations and combined antiviral and immunomodulatory therapies.

Global Dynamics of Avian Influenza Epidemic Models with Psychological Effect

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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.

Global dynamics of avian influenza epidemic models with psychological effect.

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Liu, Sanhong; Pang, Liuyong; Ruan, Shigui; Zhang, Xinan

2015-01-01

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.

Demographic and spatiotemporal patterns of avian influenza infection at the continental scale, and in relation to annual life cycle of a migratory host

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Nallar, Rodolfo; Papp, Zsuzsanna; Epp, Tasha; Leighton, Frederick A.; Swafford, Seth R.; DeLiberto, Thomas J.; Dusek, Robert J.; Ip, Hon S.; Hall, Jeffrey S.; Berhane, Yohannes; Gibbs, Samantha E.J.; Soos, Catherine

2015-01-01

Since the spread of highly pathogenic avian influenza (HPAI) H5N1 in the eastern hemisphere, numerous surveillance programs and studies have been undertaken to detect the occurrence, distribution, or spread of avian influenza viruses (AIV) in wild bird populations worldwide. To identify demographic determinants and spatiotemporal patterns of AIV infection in long distance migratory waterfowl in North America, we fitted generalized linear models with binominal distribution to analyze results from 13,574 blue-winged teal (Anas discors, BWTE) sampled in 2007 to 2010 year round during AIV surveillance programs in Canada and the United States. Our analyses revealed that during late summer staging (July-August) and fall migration (September-October), hatch year (HY) birds were more likely to be infected than after hatch year (AHY) birds, however there was no difference between age categories for the remainder of the year (winter, spring migration, and breeding period), likely due to maturing immune systems and newly acquired immunity of HY birds. Probability of infection increased non-linearly with latitude, and was highest in late summer prior to fall migration when densities of birds and the proportion of susceptible HY birds in the population are highest. Birds in the Central and Mississippi flyways were more likely to be infected compared to those in the Atlantic flyway. Seasonal cycles and spatial variation of AIV infection were largely driven by the dynamics of AIV infection in HY birds, which had more prominent cycles and spatial variation in infection compared to AHY birds. Our results demonstrate demographic as well as seasonal, latitudinal and flyway trends across Canada and the US, while illustrating the importance of migratory host life cycle and age in driving cyclical patterns of prevalence.

An overview of the recent outbreaks of the avian-origin influenza A (H7N9 virus in the human

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Ren-Bin Tang

2013-05-01

Full Text Available Since the first human infection with influenza A (H7N9 viruses have been identified in Shanghai on March 31, 2013, the latest variant of the avian flu virus has spread across four Chinese provinces recently. Human infections with avian influenza are rare and this is the first time that human infection with a low pathogenic avian influenza A virus has been associated with fatal outcome. To date (May 5th, 2013, China had reported 128 confirmed H7N9 infections in human, among 27 died. Most reported cases have severe respiratory illness resulting in severe pneumonia and in some cases have died. No evidence of sustained human-to -humans at this time, however, there is one family cluster with two confirmed cases for which human-to-human transmission cannot be ruled out. Recent evidence showed that the gene sequences of this novel H7N9 virus is primarily zoonotic and may be better adapted than other avian influenza viruses to infect human. Effective global infection control is urgently needed, and further surveillance and analyses should be undertaken to identify the source and mode of transmission of these viruses.

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

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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.

Corneal Opacity in Domestic Ducks Experimentally Infected With H5N1 Highly Pathogenic Avian Influenza Virus.

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Yamamoto, Y; Nakamura, K; Yamada, M; Mase, M

2016-01-01

Domestic ducks can be a key factor in the regional spread of H5N1 highly pathogenic avian influenza (HPAI) virus in Asia. The authors performed experimental infections to examine the relationship between corneal opacity and H5N1 HPAI virus infection in domestic ducks (Anas platyrhyncha var domestica). A total of 99 domestic ducks, including 3 control birds, were used in the study. In experiment 1, when domestic ducks were inoculated intranasally with 2 H5N1 HPAI viruses, corneal opacity appeared more frequently than neurologic signs and mortality. Corneal ulceration and exophthalmos were rare findings. Histopathologic examinations of the eyes of domestic ducks in experiment 2 revealed that corneal opacity was due to the loss of corneal endothelial cells and subsequent keratitis with edema. Influenza viral antigen was detected in corneal endothelial cells and some other ocular cells by immunohistochemistry. Results suggest that corneal opacity is a characteristic and frequent finding in domestic ducks infected with the H5N1 HPAI virus. Confirming this ocular change may improve the detection rate of infected domestic ducks in the field. © The Author(s) 2015.

Avian influenza A (H5N1)

NARCIS (Netherlands)

de Jong, Menno D.; Hien, Tran Tinh

2006-01-01

Since their reemergence in 2003, highly pathogenic avian influenza A (H5N1) viruses have reached endemic levels among poultry in several southeast Asian countries and have caused a still increasing number of more than 100 reported human infections with high mortality. These developments have ignited

Avian Influenza: a global threat needing a global solution

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Koh GCH

2008-11-01

Full Text Available Abstract There have been three influenza pandemics since the 1900s, of which the 1919–1919 flu pandemic had the highest mortality rates. The influenza virus infects both humans and birds, and mutates using two mechanisms: antigenic drift and antigenic shift. Currently, the H5N1 avian flu virus is limited to outbreaks among poultry and persons in direct contact to infected poultry, but the mortality rate among infected humans is high. Avian influenza (AI is endemic in Asia as a result of unregulated poultry rearing in rural areas. Such birds often live in close proximity to humans and this increases the chance of genetic re-assortment between avian and human influenza viruses which may produce a mutant strain that is easily transmitted between humans. Once this happens, a global pandemic is likely. Unlike SARS, a person with influenza infection is contagious before the onset of case-defining symptoms which limits the effectiveness of case isolation as a control strategy. Researchers have shown that carefully orchestrated of public health measures could potentially limit the spread of an AI pandemic if implemented soon after the first cases appear. To successfully contain and control an AI pandemic, both national and global strategies are needed. National strategies include source surveillance and control, adequate stockpiles of anti-viral agents, timely production of flu vaccines and healthcare system readiness. Global strategies such as early integrated response, curbing the disease outbreak at source, utilization of global resources, continuing research and open communication are also critical.

Rational design of avian metapneumovirus live attenuated vaccines by inhibiting viral messenger RNA cap methyltransferase

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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 ...

Avian Flu (H7N9) in China

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... 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 ...

Avian Influenza A (H7N9) Virus

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... August 7, 2017 Increase in Human Infections with Avian Influenza A(H7N9) Virus During the Fifth Epidemic — China, October 2016–February 2017 Antigenic and genetic characteristics of zoonotic influenza viruses and candidate vaccine viruses developed for ...

Viral and Host Factors Required for Avian H5N1 Influenza A Virus Replication in Mammalian Cells

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Hong Zhang

2013-06-01

Full Text Available Following the initial and sporadic emergence into humans of highly pathogenic avian H5N1 influenza A viruses in Hong Kong in 1997, we have come to realize the potential for avian influenza A viruses to be transmitted directly from birds to humans. Understanding the basic viral and cellular mechanisms that contribute to infection of mammalian species with avian influenza viruses is essential for developing prevention and control measures against possible future human pandemics. Multiple physical and functional cellular barriers can restrict influenza A virus infection in a new host species, including the cell membrane, the nuclear envelope, the nuclear environment, and innate antiviral responses. In this review, we summarize current knowledge on viral and host factors required for avian H5N1 influenza A viruses to successfully establish infections in mammalian cells. We focus on the molecular mechanisms underpinning mammalian host restrictions, as well as the adaptive mutations that are necessary for an avian influenza virus to overcome them. It is likely that many more viral and host determinants remain to be discovered, and future research in this area should provide novel and translational insights into the biology of influenza virus-host interactions.

Avian metapneumovirus infection of chicken and turkey tracheal organ cultures: comparison of virus-host interactions.

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Hartmann, Sandra; Sid, Hicham; Rautenschlein, Silke

2015-01-01

Avian metapneumovirus (aMPV) is a pathogen with worldwide distribution, which can cause high economic losses in infected poultry. aMPV mainly causes infection of the upper respiratory tract in both chickens and turkeys, although turkeys seem to be more susceptible. Little is known about virus-host interactions at epithelial surfaces after aMPV infection. Tracheal organ cultures (TOC) are a suitable model to investigate virus-host interaction in the respiratory epithelium. Therefore, we investigated virus replication rates and lesion development in chicken and turkey TOC after infection with a virulent aMPV subtype A strain. Aspects of the innate immune response, such as interferon-α and inducible nitric oxide synthase mRNA expression, as well as virus-induced apoptosis were determined. The aMPV-replication rate was higher in turkey (TTOC) compared to chicken TOC (CTOC) (P < 0.05), providing circumstantial evidence that indeed turkeys may be more susceptible. The interferon-α response was down-regulated from 2 to 144 hours post infection in both species compared to virus-free controls (P < 0.05); this was more significant for CTOC than TTOC. Inducible nitric oxide synthase expression was significantly up-regulated in aMPV-A-infected TTOC and CTOC compared to virus-free controls (P < 0.05). However, the results suggest that NO may play a different role in aMPV pathogenesis between turkeys and chickens as indicated by differences in apoptosis rate and lesion development between species. Overall, our study reveals differences in innate immune response regulation and therefore may explain differences in aMPV - A replication rates between infected TTOC and CTOC, which subsequently lead to more severe clinical signs and a higher rate of secondary infections in turkeys.

Bat lung epithelial cells show greater host species-specific innate resistance than MDCK cells to human and avian influenza viruses.

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Slater, Tessa; Eckerle, Isabella; Chang, Kin-Chow

2018-04-10

With the recent discovery of novel H17N10 and H18N11 influenza viral RNA in bats and report on high frequency of avian H9 seroconversion in a species of free ranging bats, an important issue to address is the extent bats are susceptible to conventional avian and human influenza A viruses. To this end, three bat species (Eidolon helvum, Carollia perspicillata and Tadarida brasiliensis) of lung epithelial cells were separately infected with two avian and two human influenza viruses to determine their relative host innate immune resistance to infection. All three species of bat cells were more resistant than positive control Madin-Darby canine kidney (MDCK) cells to all four influenza viruses. TB1-Lu cells lacked sialic acid α2,6-Gal receptors and were most resistant among the three bat species. Interestingly, avian viruses were relatively more replication permissive in all three bat species of cells than with the use of human viruses which suggest that bats could potentially play a role in the ecology of avian influenza viruses. Chemical inhibition of the JAK-STAT pathway in bat cells had no effect on virus production suggesting that type I interferon signalling is not a major factor in resisting influenza virus infection. Although all three species of bat cells are relatively more resistant to influenza virus infection than control MDCK cells, they are more permissive to avian than human viruses which suggest that bats could have a contributory role in the ecology of avian influenza viruses.

Avian zoonoses – a review

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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

Genetic and biological characterisation of an avian-like H1N2 swine influenza virus generated by reassortment of circulating avian-like H1N1 and H3N2 subtypes in Denmark.

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Trebbien, Ramona; Bragstad, Karoline; Larsen, Lars Erik; Nielsen, Jens; Bøtner, Anette; Heegaard, Peter M H; Fomsgaard, Anders; Viuff, Birgitte; Hjulsager, Charlotte Kristiane

2013-09-18

The influenza A virus subtypes H1N1, H1N2 and H3N2 are the most prevalent subtypes in swine. In 2003, a reassorted H1N2 swine influenza virus (SIV) subtype appeared and became prevalent in Denmark. In the present study, the reassortant H1N2 subtype was characterised genetically and the infection dynamics compared to an "avian-like" H1N1 virus by an experimental infection study. Sequence analyses were performed of the H1N2 virus. Two groups of pigs were inoculated with the reassortant H1N2 virus and an "avian-like" H1N1 virus, respectively, followed by inoculation with the opposite subtype four weeks later. Measurements of HI antibodies and acute phase proteins were performed. Nasal virus excretion and virus load in lungs were determined by real-time RT-PCR. The phylogenetic analysis revealed that the reassorted H1N2 virus contained a European "avian-like" H1-gene and a European "swine-like" N2-gene, thus being genetically distinct from most H1N2 viruses circulating in Europe, but similar to viruses reported in 2009/2010 in Sweden and Italy. Sequence analyses of the internal genes revealed that the reassortment probably arose between circulating Danish "avian-like" H1N1 and H3N2 SIVs. Infected pigs developed cross-reactive antibodies, and increased levels of acute phase proteins after inoculations. Pigs inoculated with H1N2 exhibited nasal virus excretion for seven days, peaking day 1 after inoculation two days earlier than H1N1 infected pigs and at a six times higher level. The difference, however, was not statistically significant. Pigs euthanized on day 4 after inoculation, had a high virus load in all lung lobes. After the second inoculation, the nasal virus excretion was minimal. There were no clinical sign except elevated body temperature under the experimental conditions. The "avian-like" H1N2 subtype, which has been established in the Danish pig population at least since 2003, is a reassortant between circulating swine "avian-like" H1N1 and H3N2. The Danish

The comparison of pathology in ferrets infected by H9N2 avian influenza viruses with different genomic features.

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Gao, Rongbao; Bai, Tian; Li, Xiaodan; Xiong, Ying; Huang, Yiwei; Pan, Ming; Zhang, Ye; Bo, Hong; Zou, Shumei; Shu, Yuelong

2016-01-15

H9N2 avian influenza virus circulates widely in poultry and has been responsible for sporadic human infections in several regions. Few studies have been conducted on the pathogenicity of H9N2 AIV isolates that have different genomic features. We compared the pathology induced by a novel reassortant H9N2 virus and two currently circulating H9N2 viruses that have different genomic features in ferrets. The results showed that the three viruses can induce infections with various amounts of viral shedding in ferrets. The novel H9N2 induced respiratory infection, but no pathological lesions were observed in lung tissues. The other two viruses induced mild to intermediate pathological lesions in lung tissues, although the clinical signs presented mildly in ferrets. The pathological lesions presented a diversity consistent with viral replication in ferrets. Copyright © 2015 Elsevier Inc. All rights reserved.

Pathogenesis of Riemerella anatipestifer in turkeys after experimental mono-infection via respiratory routes or dual infection together with the avian metapneumovirus.

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Rubbenstroth, Dennis; Ryll, Martin; Behr, Klaus-Peter; Rautenschlein, Silke

2009-12-01

Riemerella anatipestifer (RA) is the causative agent of septicaemic and exudative diseases in a variety of bird species. Despite numerous outbreaks, little is known about the pathogenicity of RA for turkeys. We investigated the development of RA-induced disease in commercial turkey poults following RA inoculation via different respiratory routes. Inoculation by aerosol or injection into the abdominal air sac led to systemic infection and mild gross lesions, including pericarditis, epicarditis and airsacculitis, which were less pronounced compared with field outbreaks. It was speculated, that viral pathogens, such as the avian metapneumovirus (aMPV), may exacerbate RA pathogenesis under field conditions. We inoculated turkey poults with virulent aMPV. Subsequently, aMPV-infected and virus-free birds were exposed 3 to 5 days later to a high dose of RA by aerosol (>10(10) colony-forming units/ml in 8 ml aerosol per 11 or 12 birds) or were inoculated 4 days later with a low RA dose (10(4.9) colony-forming units per bird) via the intranasal route. Intranasal RA inoculation with the low bacterial dose led to a respiratory and systemic RA infection in aMPV-infected birds, while virus-free birds remained RA-negative. Following exposure to a high RA dose by aerosol, aMPV-infected groups showed slightly enhanced incidences of gross lesions and RA re-isolation. The present study clearly confirms that RA is pathogenic for turkeys after experimental inoculation via respiratory routes, which are speculated to be the natural route of infection. However, experimental models in this study did not reproduce the severity of RA-related disease as observed under field conditions, which emphasizes the importance of other contributing factors. aMPV-induced respiratory lesions may serve as a predisposing factor for the establishment of RA infection, since they favour colonization of the bacterium.

Pathology of whooper swans (Cygnus cygnus) infected with H5N1 avian influenza virus in Akita, Japan, in 2008.

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Ogawa, Shuji; Yamamoto, Yu; Yamada, Manabu; Mase, Masaji; Nakamura, Kikuyasu

2009-10-01

Two (1 adult and 1 young bird) of 4 H5N1-highly-pathogenic-avian-influenza (HPAI)-virus-infected whooper swans in Akita, Japan, in 2008 were investigated pathologically. Macroscopically, white spots with hemorrhages were scattered in the pancreas in the adult bird. Histologically, the adult bird had severe necrotizing pancreatitis and mild nonpurulent encephalitis. The young bird had severe nonpurulent encephalitis and nonpurulent enteric ganglionitis, and intestinal venous wall thickening. Virus antigens were detected in the lesions of pancreatitis in the adult bird and of encephalitis in adult and young birds. These findings suggest that the swans died or became moribund due to neurological disorders and necrotizing pancreatitis caused by H5N1 HPAI virus infection.

An overview of the recent outbreaks of the avian-origin influenza A (H7N9) virus in the human.

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Tang, Ren-Bin; Chen, Hui-Lan

2013-05-01

Since the first human infection with influenza A (H7N9) viruses have been identified in Shanghai on March 31, 2013, the latest variant of the avian flu virus has spread across four Chinese provinces recently. Human infections with avian influenza are rare and this is the first time that human infection with a low pathogenic avian influenza A virus has been associated with fatal outcome. To date (May 5(th), 2013), China had reported 128 confirmed H7N9 infections in human, among 27 died. Most reported cases have severe respiratory illness resulting in severe pneumonia and in some cases have died. No evidence of sustained human-to -humans at this time, however, there is one family cluster with two confirmed cases for which human-to-human transmission cannot be ruled out. Recent evidence showed that the gene sequences of this novel H7N9 virus is primarily zoonotic and may be better adapted than other avian influenza viruses to infect human. Effective global infection control is urgently needed, and further surveillance and analyses should be undertaken to identify the source and mode of transmission of these viruses. Copyright © 2013. Published by Elsevier B.V.

Avian trichomonosis in spotted owls (Strix occidentalis: Indication of opportunistic spillover from prey

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Krysta H. Rogers

2016-12-01

Full Text Available Avian trichomonosis, caused by the flagellated protozoan parasite Trichomonas gallinae, has variable pathogenicity among bird species ranging from asymptomatic infections to severe disease periodically manifesting in epidemic mortality. Traditionally, columbids are identified as highly susceptible to infection with occasional spillover into raptors that prey on infected birds. We identified avian trichomonosis in two dead California spotted owls (Strix occidentalis occidentalis and three dead northern spotted owls (S. o. caurina in California during 2011–2015; infection was confirmed in four owls by PCR. Pathologic lesions associated with trichomonosis in the owls included caseonecrotic lesions of the upper palate accompanied by oropharyngitis, cellulitis, myositis, and/or sinusitis. Spotted owls are known to mainly feed on small mammals; therefore, the source of infection as well as the significance of the disease in spotted owls is unclear. These owl trichomonosis cases coincided temporally and spatially with three trichomonosis epidemics in band-tailed pigeons (Patagioenas fasciata monilis. The same parasite, T. gallinae subtype A2, was isolated from the spotted owls and band-tailed pigeons, suggesting the owls became infected when opportunistically feeding on pigeons during mortality events. Avian trichomonosis is an important factor in the decline of the Pacific Coast band-tailed pigeon population with near-annual mortality events during the last 10 years and could have conservation implications for raptor species at risk, particularly those that are facing multiple threats.

Surveillance for early detection of low pathogenicity avian influenza in poultry

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Comin, A.

2012-01-01

Infection with low pathogenicity avian influenza (LPAI) virus is widespread and has led to outbreaks in domestic birds in many countries. Although infection does not pose a serious concern for animal heath, LPAI virus subtypes H5 and H7 can mutate into the highly pathogenic form (HPAI), which can

Experimental infection of swans and geese with highly pathogenic avian influenza virus (H5N1) of Asian lineage.

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Brown, Justin D; Stallknecht, David E; Swayne, David E

2008-01-01

The role of wild birds in the epidemiology of the Asian lineage highly pathogenic avian influenza (HPAI) virus subtype H5N1 epizootic and their contribution to the spread of the responsible viruses in Eurasia and Africa are unclear. To better understand the potential role of swans and geese in the epidemiology of this virus, we infected 4 species of swans and 2 species of geese with an HPAI virus of Asian lineage recovered from a whooper swan in Mongolia in 2005, A/whooper swan/Mongolia/244/2005 (H5N1). The highest mortality rates were observed in swans, and species-related differences in clinical illness and viral shedding were evident. These results suggest that the potential for HPAI (H5N1) viral shedding and the movement of infected birds may be species-dependent and can help explain observed deaths associated with HPAI (H5N1) infection in anseriforms in Eurasia.

Comparative analysis of chest radiological findings between avian human influenza and SARS

International Nuclear Information System (INIS)

Cai Mingjin; Mai Weiwen; Xian Jianxing; Zhang Jiayun; Lin Wenjian; Wei Liping; Chen Jincheng

2008-01-01

Objective: To study the chest radiological findings of a mortal avian human influenza case. Methods: One patient in our hospital was proved to be infected avian human influenza in Guangdong province on March 1, 2006. The Clinical appearances and chest radiological findings of this case were retrospectively analyzed and compared with that of 3 mortal SARS cases out of 16 cases in 2003. Results: Large consolidated areas in left lower lobe was showed in pulmonary radiological findings of this patient and soon developed into ARDS (adult respiratory distress syndrome). However, the pulmonary radiological findings had no characteristic. Characteristics of soaring size and number during short term appeared in SARS instead of avian human influenza. Final diagnosis was up to the etiology and serology examination. Conclusion: Bronchial dissemination was not observed in this avian human influenza case. Pay attention to the avian human influenza in spite of no history of contract with sick or dead poultry in large city. (authors)

Expression of avian β-defensins and Toll-like receptor genes in the rooster epididymis during growth and Salmonella infection.

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Anastasiadou, M; Avdi, M; Michailidis, G

2013-08-01

The epididymis is an organ involved in the maturation, transport, and storage of sperm prior to ejaculation. As epididymis is exposed to a constant risk of inflammatory conditions that may lead to transient or permanent sterility, protection of this organ from pathogens is an essential aspect of reproductive physiology. The families of antimicrobial peptides β-defensins and the pattern-recognition receptors Toll-like (TLR) mediate innate immunity in various vertebrates including avian species. As rooster infertility is a major concern in the poultry industry, the objectives of this study were to determine the expression profile of the entire family of the avian β-defensins (AvBD) and TLR genes in the rooster epididymis, to investigate whether sexual maturation affects their epididymidal mRNA abundance and to determine the changes in their expression levels in response to Salmonella enteritidis (SE) infection in the epididymis of sexually mature roosters. RNA was extracted from the epididymis of healthy pubertal, sexually mature and aged birds, and from sexually mature SE infected birds. RT-PCR analysis revealed that 10 members of the AvBD and nine members of the TLR gene families were expressed in the epididymis. Quantitative real-time PCR analysis revealed that the epididymidal mRNA abundance of certain AvBD and TLR genes was developmentally regulated with respect to sexual maturation. SE infection resulted in a significant induction of AvBD 1, 9, 10, 12 and 14, as well as TLR 1-2, 2-1, 2-2, 4, 5 and 7 genes, in the epididymis of sexually mature roosters, compared to healthy birds of the same age. These findings provide strong evidence to suggest that the rooster epididymis is capable of initiating an inflammatory response to Salmonella, through activation of certain members of the AvBD and TLR gene families. Copyright © 2013 Elsevier B.V. All rights reserved.

Avian and human influenza A virus receptors in trachea and lung of animals.

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Thongratsakul, Sukanya; Suzuki, Yasuo; Hiramatsu, Hiroaki; Sakpuaram, Thavajchai; Sirinarumitr, Theerapol; Poolkhet, Chaithep; Moonjit, Pattra; Yodsheewan, Rungrueang; Songserm, Thaweesak

2010-12-01

Influenza A viruses are capable of crossing the specific barrier between human beings and animals resulting in interspecies transmission. The important factor of potential infectivity of influenza A viruses is the suitability of the receptor binding site of the host and viruses. The affinities of avian and human influenza virus to bind with the receptors and the distributions of receptors in animals are different. This study aims to investigate the anatomical distribution of avian and human influenza virus receptors using the double staining lectin histochemistry method. Double staining of lectin histochemistry was performed to identify both SA alpha2,3 Gal and SA alpha2,6 Gal receptors in trachea and lung tissue of dogs, cats, tigers, ferret, pigs, ducks and chickens. We have demonstrated that avian and human influenza virus receptors were abundantly present in trachea, bronchus and bronchiole, but in alveoli of dogs, cats and tigers showed SA alpha2,6 Gal only. Furthermore, endothelial cells in lung tissues showed presence of SA alpha2,3 Gal. The positive sites of both receptors in respiratory tract, especially in the trachea, suggest that all mammalian species studied can be infected with avian influenza virus. These findings suggested that dogs and cats in close contact with humans should be of greater concern as an intermediate host for avian influenza A in which there is the potential for viral adaptation and reassortment.

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.

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; Pérez-Ramírez, Elisa; Busquets, Núria; Dolz, Roser; Ramis, Antonio; Darji, Ayub; Abad, Francesc Xavier; Valle, Rosa; Chaves, Aida; Vergara-Alert, Júlia; Barral, Marta; Höfle, Ursula; Majó, Natàlia

2011-02-07

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.

Avian influenza

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Bird flu; H5N1; H5N2; H5N8; H7N9; Avian influenza A (HPAI) H5 ... The first avian influenza in humans was reported in Hong Kong in 1997. It was called avian influenza (H5N1). The outbreak was linked ...

Molecular detection of avian pox virus from nodular skin and mucosal fibrinonecrotic lesions of Iranian backyard poultry.

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Gholami-Ahangaran, Majid; Zia-Jahromi, Noosha; Namjoo, Abdolrasul

2014-02-01

In recent years, some outbreaks of skin lesions suspected to be avian pox were observed in the backyard poultry in different parts of western areas in Iran. Consequently, 328 backyard poultries with suspected signs of avian pox virus infection were sampled. All birds showed nodular lesions on unfeathered head skin and/or fibronecrotic lesions on mucus membrane of the oral cavity and upper respiratory tract. For histopathological analysis, the sections of tissue samples from cutaneous lesions of examined birds were stained with H&E method. For PCR, after DNA extraction a 578-bp fragment of avian pox virus from 4b core protein gene was amplified. Results showed 217 and 265 out of 328 (66.1 and 80.7%, respectively) samples were positive for avian pox virus on histopathological and PCR examination, respectively. In this study, the samples that had intracytoplasmic inclusion bodies on pathologic examination were PCR positive. This study revealed that PCR is a valuable tool for identification of an avian pox virus and that the frequency of pox infection in backyard poultry in western areas of Iran is high.

Inhibition of Avian Influenza A Virus Replication in Human Cells by Host Restriction Factor TUFM Is Correlated with Autophagy.

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Kuo, Shu-Ming; Chen, Chi-Jene; Chang, Shih-Cheng; Liu, Tzu-Jou; Chen, Yi-Hsiang; Huang, Sheng-Yu; Shih, Shin-Ru

2017-06-13

Avian influenza A viruses generally do not replicate efficiently in human cells, but substitution of glutamic acid (Glu, E) for lysine (Lys, K) at residue 627 of avian influenza virus polymerase basic protein 2 (PB2) can serve to overcome host restriction and facilitate human infectivity. Although PB2 residue 627 is regarded as a species-specific signature of influenza A viruses, host restriction factors associated with PB2 627 E have yet to be fully investigated. We conducted immunoprecipitation, followed by differential proteomic analysis, to identify proteins associating with PB2 627 K (human signature) and PB2 627 E (avian signature) of influenza A/WSN/1933(H1N1) virus, and the results indicated that Tu elongation factor, mitochondrial (TUFM), had a higher binding affinity for PB2 627 E than PB2 627 K in transfected human cells. Stronger binding of TUFM to avian-signature PB2 590 G/ 591 Q and PB2 627 E in the 2009 swine-origin pandemic H1N1 and 2013 avian-origin H7N9 influenza A viruses was similarly observed. Viruses carrying avian-signature PB2 627 E demonstrated increased replication in TUFM-deficient cells, but viral replication decreased in cells overexpressing TUFM. Interestingly, the presence of TUFM specifically inhibited the replication of PB2 627 E viruses, but not PB2 627 K viruses. In addition, enhanced levels of interaction between TUFM and PB2 627 E were noted in the mitochondrial fraction of infected cells. Furthermore, TUFM-dependent autophagy was reduced in TUFM-deficient cells infected with PB2 627 E virus; however, autophagy remained consistent in PB2 627 K virus-infected cells. The results suggest that TUFM acts as a host restriction factor that impedes avian-signature influenza A virus replication in human cells in a manner that correlates with autophagy. IMPORTANCE An understanding of the mechanisms that influenza A viruses utilize to shift host tropism and the identification of host restriction factors that can limit infection are both

Proteomics analysis of the DF-1 chicken fibroblasts infected with avian reovirus strain S1133.

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Wen-Ting Chen

Full Text Available BACKGROUND: Avian reovirus (ARV is a member of the Orthoreovirus genus in the Reoviridae family. It is the etiological agent of several diseases, among which viral arthritis and malabsorption syndrome are the most commercially important, causing considerable economic losses in the poultry industry. Although a small but increasing number of reports have characterized some aspects of ARV infection, global changes in protein expression in ARV-infected host cells have not been examined. The current study used a proteomics approach to obtain a comprehensive view of changes in protein levels in host cells upon infection by ARV. METHODOLOGY AND PRINCIPAL FINDINGS: The proteomics profiles of DF-1 chicken fibroblast cells infected with ARV strain S1133 were analyzed by two-dimensional differential-image gel electrophoresis. The majority of protein expression changes (≥ 1.5 fold, p<0.05 occurred at 72 h post-infection. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry identified 51 proteins with differential expression levels, including 25 that were upregulated during ARV infection and 26 that were downregulated. These proteins were divided into eight groups according to biological function: signal transduction, stress response, RNA processing, the ubiquitin-proteasome pathway, lipid metabolism, carbohydrate metabolism, energy metabolism, and cytoskeleton organization. They were further examined by immunoblotting to validate the observed alterations in protein expression. CONCLUSION/SIGNIFICANCE: This is the first report of a time-course proteomic analysis of ARV-infected host cells. Notably, all identified proteins involved in signal transduction, RNA processing, and the ubiquitin-proteasome pathway were downregulated in infected cells, whereas proteins involved in DNA synthesis, apoptosis, and energy production pathways were upregulated. In addition, other differentially expressed proteins were linked with the cytoskeleton

Avian Biotechnology.

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Nakamura, Yoshiaki

2017-01-01

Primordial germ cells (PGCs) generate new individuals through differentiation, maturation and fertilization. This means that the manipulation of PGCs is directly linked to the manipulation of individuals, making PGCs attractive target cells in the animal biotechnology field. A unique biological property of avian PGCs is that they circulate temporarily in the vasculature during early development, and this allows us to access and manipulate avian germ lines. Following the development of a technique for transplantation, PGCs have become central to avian biotechnology, in contrast to the use of embryo manipulation and subsequent transfer to foster mothers, as in mammalian biotechnology. Today, avian PGC transplantation combined with recent advanced manipulation techniques, including cell purification, cryopreservation, depletion, and long-term culture in vitro, have enabled the establishment of genetically modified poultry lines and ex-situ conservation of poultry genetic resources. This chapter introduces the principles, history, and procedures of producing avian germline chimeras by transplantation of PGCs, and the current status of avian germline modification as well as germplasm cryopreservation. Other fundamental avian reproductive technologies are described, including artificial insemination and embryo culture, and perspectives of industrial applications in agriculture and pharmacy are considered, including poultry productivity improvement, egg modification, disease resistance impairment and poultry gene "pharming" as well as gene banking.

[Epidemiological perspectives on SARS and avian influenza].

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del Rey Calero, Juan

2004-01-01

SARS is a respiratory infection caused by Coronavirus (Nidoviruses, RNA) from which 3 groups are known. Group 1 affects dogs, cats, pigs, and the human agent is 229 E. Group 2 affects bovines or rodents, and the human agent is OC43. And group 3 corresponds to the avian pathology.... The epidemics emerged on February 2003 in Guangdong, South China, due to consumption of exotic animals (Civeta, etc.), and it spread through interperson contagion to other regions in Asia, America and Europe. Incubation period is about 2-7 days. Transmission Of the virus is person-to person, but also by excretions and residual water. Basic reproductive rate is 2 to 4, and it is considered that 2.7 persons are infected from the initial case. In June 2003, SARS affected over 8,000 people and 774 were killed. Mortality approaches to 10%, and it is higher among older people rising up to 50% in those aged over 65 years. It is important to quickly establish action protocols regarding clinical, epidemiological and prevention aspects. Avian influenza is an infection caused by type A Influenza Orthomixovirus, in which migration birds and wild ducks are the main reservoir. Avian viruses correspond to H5, H7, H9. In 1997 it was observed that type AH5N1 jumped interspecies barrier and affected 18 humans, and 6 of them died. At the end of 2003 and in 2004 this type of poultry flu was described in Asia. FAO has emphasized that sacrifice of chicken in affected farms is the most effective measure to fight against the disease. It has also been established suppression of imports from these countries. There is no evidence on interperson contagion from chicken contagion, nor on food-borne contagion to humans.

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

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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

2014-01-01

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. PMID:24937647

Effect of housing arrangement on fecal-oral transmission of avian hepatitis E virus in chicken flocks.

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Liu, Baoyuan; Sun, Yani; Chen, Yiyang; Du, Taofeng; Nan, Yuchen; Wang, Xinjie; Li, Huixia; Huang, Baicheng; Zhang, Gaiping; Zhou, En-Min; Zhao, Qin

2017-09-07

Avian hepatitis E virus (HEV) infection is common in chicken flocks in China, as currently no measures exist to prevent the spread of the disease. In this study, we analyzed the effect of caged versus cage-free housing arrangements on avian HEV transmission. First, 127 serum and 110 clinical fecal samples were collected from 4 chicken flocks including the two arrangements in Shaanxi Province, China and tested for HEV antibodies and/or virus. Concurrently, 36 specific-pathogen-free chickens were divided equally into four experimental living arrangement groups, designated cage-free (Inoculated), caged (Inoculated), cage-free (Negative) and caged (Negative) groups. In caged groups, three cages contained 3 chickens each. Three chickens each from cage-free (Inoculated) and caged (Inoculated) groups (one chicken of each cage) were inoculated by cutaneous ulnar vein with the same dose of avian HEV, respectively. The cage-free (Negative) and caged (Negative) groups served as negative control. Serum and fecal samples were collected at 1 to 7 weeks post-inoculation (wpi) and liver lesions were scored at 7 wpi. The results of serology showed that the avian HEV infection rate (54.10%) of the cage-free chickens was significantly higher than the one (12.12%) for caged chickens (P chickens (6) was significantly higher than the one for the uninoculated caged birds (2), as evidenced by seroconversion, fecal virus shedding, viremia and gross and microscopic liver lesions. These results suggest that reduction of contact with feces as seen in the caged arrangement of housing chickens can reduce avian HEV transmission. This study provides insights for prevention and control of avian HEV infection in chicken flocks.

Access to health information may improve behavior in preventing Avian influenza among women

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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

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

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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.

Avian keratin disorder of Alaska black-capped chickadees is associated with Poecivirus infection

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Zylberberg, Maxine; Van Hemert, Caroline R.; Handel, Colleen M.; DeRisi, Joseph L.

2018-01-01

BackgroundAvian keratin disorder (AKD) is an epizootic of debilitating beak deformities, first documented in black-capped chickadees (Poecile atricapillus) in Alaska during the late 1990s. Similar deformities have now been recorded in dozens of species of birds across multiple continents. Despite this, the etiology of AKD has remained elusive, making it difficult to assess the impacts of this disease on wild populations. We previously identified an association between infection with a novel picornavirus, Poecivirus, and AKD in a small cohort of black-capped chickadees.MethodsTo test if the association between Poecivirus and AKD holds in a larger study population, we used targeted PCR followed by Sanger sequencing to screen 124 symptomatic and asymptomatic black-capped chickadees for Poecivirus infection. We further compared the efficacy of multiple non-terminal field sampling methods (buccal swabs, cloacal swabs, fecal samples, and blood samples) for Poecivirus screening. Finally, we used both in situ hybridization and a strand-specific expression assay to localize Poecivirus to beak tissue of AKD-positive individuals and to determine if virus is actively replicating in beak tissue.ResultsPoecivirus was detected in 28/28 (100%) individuals with AKD, but only 9/96 (9.4%) asymptomatic individuals with apparently normal beaks (p capped chickadee. Poecivirus continues to warrant further investigation as a candidate agent of AKD.

DC-SIGN mediates avian H5N1 influenza virus infection in cis and in trans

International Nuclear Information System (INIS)

Wang, S.-F.; Huang, Jason C.; Lee, Y.-M.; Liu, S.-J.; Chan, Yu-Jiun; Chau, Y.-P.; Chong, P.; Chen, Y.-M.A.

2008-01-01

DC-SIGN, a C-type lectin receptor expressed in dendritic cells (DCs), has been identified as a receptor for human immunodeficiency virus type 1, hepatitis C virus, Ebola virus, cytomegalovirus, dengue virus, and the SARS coronavirus. We used H5N1 pseudotyped and reverse-genetics (RG) virus particles to study their ability to bind with DC-SIGN. Electronic microscopy and functional assay results indicate that pseudotyped viruses containing both HA and NA proteins express hemagglutination and are capable of infecting cells expressing α-2,3-linked sialic acid receptors. Results from a capture assay show that DC-SIGN-expressing cells (including B-THP-1/DC-SIGN and T-THP-1/DC-SIGN) and peripheral blood dendritic cells are capable of transferring H5N1 pseudotyped and RG virus particles to target cells; this action can be blocked by anti-DC-SIGN monoclonal antibodies. In summary, (a) DC-SIGN acts as a capture or attachment molecule for avian H5N1 virus, and (b) DC-SIGN mediates infections in cis and in trans

Avian Plasmodium in Eastern Austrian mosquitoes.

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Schoener, Ellen; Uebleis, Sarah Susanne; Butter, Julia; Nawratil, Michaela; Cuk, Claudia; Flechl, Eva; Kothmayer, Michael; Obwaller, Adelheid G; Zechmeister, Thomas; Rubel, Franz; Lebl, Karin; Zittra, Carina; Fuehrer, Hans-Peter

2017-09-29

Insect vectors, namely mosquitoes (Diptera: Culicidae), are compulsory for malaria parasites (Plasmodium spp.) to complete their life cycle. Despite this, little is known about vector competence of different mosquito species for the transmission of avian malaria parasites. In this study, nested PCR was used to determine Plasmodium spp. occurrence in pools of whole individuals, as well as the diversity of mitochondrial cytochrome b gene sequences in wild-caught mosquitoes sampled across Eastern Austria in 2013-2015. A total of 45,749 mosquitoes in 2628 pools were collected, of which 169 pools (6.43%) comprising 9 mosquito species were positive for avian Plasmodium, with the majority of positives in mosquitoes of Culex pipiens s.l./Culex torrentium. Six different avian Plasmodium lineages were found, the most common were Plasmodium vaughani SYAT05, Plasmodium sp. Linn1 and Plasmodium relictum SGS1. In 2014, mosquitoes of the Culex pipiens complex were genetically identified and Culex pipiens f. pipiens presented with the highest number of avian Plasmodium positives (n = 37; 16.74%). Despite this, the minimum infection rate (MIR) was highest in Culex torrentium (5.36%) and Culex pipiens f. pipiens/f. molestus hybrids (5.26%). During 2014 and 2015, seasonal and annual changes in Plasmodium lineage distribution were also observed. In both years P. vaughani SYAT05 dominated at the beginning of the sampling period to be replaced later in the year by P. relictum SGS1 (2014) and Plasmodium sp. Linn1 (2015). This is the first large-scale study of avian Plasmodium parasites in Austrian mosquitoes. These results are of special interest, because molecular identification of the taxa of the Cx. pipiens complex and Cx. torrentium enabled the determination of Plasmodium prevalence in the different mosquito taxa and hybrids of this complex. Since pools of whole insects were used, it is not possible to assert any vector competence in any of the examined mosquitoes, but the results

Human influenza is more effective than avian influenza at antiviral suppression in airway cells.

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Hsu, Alan Chen-Yu; Barr, Ian; Hansbro, Philip M; Wark, Peter A

2011-06-01

Airway epithelial cells are the initial site of infection with influenza viruses. The innate immune responses of airway epithelial cells to infection are important in limiting virus replication and spread. However, relatively little is known about the importance of this innate antiviral response to infection. Avian influenza viruses are a potential source of future pandemics; therefore, it is critical to examine the effectiveness of the host antiviral system to different influenza viruses. We used a human influenza (H3N2) and a low-pathogenic avian influenza (H11N9) to assess and compare the antiviral responses of Calu-3 cells. After infection, H3N2 replicated more effectively than the H11N9 in Calu-3 cells. This was not due to differential expression of sialic acid residues on Calu-3 cells, but was attributed to the interference of host antiviral responses by H3N2. H3N2 induced a delayed antiviral signaling and impaired type I and type III IFN induction compared with the H11N9. The gene encoding for nonstructural (NS) 1 protein was transfected into the bronchial epithelial cells (BECs), and the H3N2 NS1 induced a greater inhibition of antiviral responses compared with the H11N9 NS1. Although the low-pathogenic avian influenza virus was capable of infecting BECs, the human influenza virus replicated more effectively than avian influenza virus in BECs, and this was due to a differential ability of the two NS1 proteins to inhibit antiviral responses. This suggests that the subversion of human antiviral responses may be an important requirement for influenza viruses to adapt to the human host and cause disease.

Seroprevalence survey of H9N2 avian influenza virus in backyard chickens around the Caspian Sea in Iran

OpenAIRE

Hadipour,MM

2010-01-01

Since 1998, an epidemic of avian influenza occurred in the Iranian poultry industry. The identified agent presented low pathogenicity, and was subtyped as an H9N2 avian influenza virus. Backyard chickens can play an important role in the epidemiology of H9N2 avian influenza virus infection. Close contact of backyard chickens with migratory birds, especially with aquatic birds, as well as neighboring poultry farms, may pose the risk of transmitting avian influenza virus, but little is known ab...

Global dynamic analysis of a H7N9 avian-human influenza model in an outbreak region.

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Chen, Yongxue; Wen, Yongxian

2015-02-21

In 2013 in China a new type of avian influenza virus, H7N9, began to infect humans and had aroused severe fatality in the infected humans. We know that the spread is from poultry to humans, and the H7N9 avian influenza is low pathogenic in the poultry world but highly pathogenic in the human world, but the transmission mechanism is unclear. Since it has no signs of human-to-human transmission and outbreaks are isolated in some cities in China, in order to investigate the transmission mechanism of human infection with H7N9 avian influenza, an eco-epidemiological model in an outbreak region is proposed and analyzed dynamically. Researches and reports show that gene mutation makes the new virus be capable of infecting humans, therefore the mutation factor is taken into account in the model. The global dynamic analysis is conducted, different thresholds are identified, persistence and global qualitative behaviors are obtained. The impact of H7N9 avian influenza on the people population is concerned. Finally, the numerical simulations are carried out to support the theoretical analysis and to investigate the disease control measures. It seems that we may take people׳s hygiene and prevention awareness factor as a significant policy to achieve the aim of both the disease control and the economic returns. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Influence of Ecological Factors on the Transmission and Stability of Avian Influenza Virus in the Environment

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Dyah Ayu Hewajuli

2014-09-01

Full Text Available Ecology is a science studying the correlation among organisms and some environmental factors. Ecological factors play an important role to transmit Avian Influenza (AI virus and influence its stability in the environment. Avian Influenza virus is classified as type A virus and belong to Orthomyxoviridae family. The virus can infect various vertebrates, mainly birds and mammals, including human. Avian Influenza virus transmission can occur through bird migration. The bird migration patterns usually occur in the large continent covers a long distance area within a certain periode hence transmit the virus from infected birds to other birds and spread to the environment. The biotic (normal flora microbes and abiotic (physical and chemical factors play important role in transmitting the virus to susceptible avian species and influence its stability in the environment. Disinfectant can inactivate the AI virus in the environment but its effectivity is influenced by the concentration, contact time, pH, temperature and organic matter.

Avian influenza A virus PB2 promotes interferon type I inducing properties of a swine strain in porcine dendritic cells

International Nuclear Information System (INIS)

Ocaña-Macchi, Manuela; Ricklin, Meret E.; Python, Sylvie; Monika, Gsell-Albert; Stech, Jürgen; Stech, Olga; Summerfield, Artur

2012-01-01

The 2009 influenza A virus (IAV) pandemic resulted from reassortment of avian, human and swine strains probably in pigs. To elucidate the role of viral genes in host adaptation regarding innate immune responses, we focussed on the effect of genes from an avian H5N1 and a porcine H1N1 IAV on infectivity and activation of porcine GM-CSF-induced dendritic cells (DC). The highest interferon type I responses were achieved by the porcine virus reassortant containing the avian polymerase gene PB2. This finding was not due to differential tropism since all viruses infected DC equally. All viruses equally induced MHC class II, but porcine H1N1 expressing the avian viral PB2 induced more prominent nuclear NF-κB translocation compared to its parent IAV. The enhanced activation of DC may be detrimental or beneficial. An over-stimulation of innate responses could result in either pronounced tissue damage or increased resistance against IAV reassortants carrying avian PB2.

Avian influenza A virus PB2 promotes interferon type I inducing properties of a swine strain in porcine dendritic cells

Energy Technology Data Exchange (ETDEWEB)

Ocana-Macchi, Manuela; Ricklin, Meret E.; Python, Sylvie; Monika, Gsell-Albert [Institute of Virology and Immunoprophylaxis, Mittelhaeusern (Switzerland); Stech, Juergen; Stech, Olga [Friedrich-Loeffler Institut, Greifswald-Insel Riems (Germany); Summerfield, Artur, E-mail: artur.summerfield@ivi.admin.ch [Institute of Virology and Immunoprophylaxis, Mittelhaeusern (Switzerland)

2012-05-25

The 2009 influenza A virus (IAV) pandemic resulted from reassortment of avian, human and swine strains probably in pigs. To elucidate the role of viral genes in host adaptation regarding innate immune responses, we focussed on the effect of genes from an avian H5N1 and a porcine H1N1 IAV on infectivity and activation of porcine GM-CSF-induced dendritic cells (DC). The highest interferon type I responses were achieved by the porcine virus reassortant containing the avian polymerase gene PB2. This finding was not due to differential tropism since all viruses infected DC equally. All viruses equally induced MHC class II, but porcine H1N1 expressing the avian viral PB2 induced more prominent nuclear NF-{kappa}B translocation compared to its parent IAV. The enhanced activation of DC may be detrimental or beneficial. An over-stimulation of innate responses could result in either pronounced tissue damage or increased resistance against IAV reassortants carrying avian PB2.

USGS role and response to highly pathogenic avian influenza

Science.gov (United States)

Harris, M. Camille; Miles, A. Keith; Pearce, John M.; Prosser, Diann J.; Sleeman, Jonathan M.; Whalen, Mary E.

2015-09-09

Avian influenza viruses are naturally occurring in wild birds such as ducks, geese, swans, and gulls. These viruses generally do not cause illness in wild birds, however, when spread to poultry they can be highly pathogenic and cause illness and death in backyard and commercial farms. Outbreaks may cause devastating agricultural economic losses and some viral strains have the potential to infect people directly. Furthermore, the combination of avian influenza viruses with mammalian viruses can result in strains with the ability to transmit from person to person, possibly leading to viruses with pandemic potential. All known pandemic influenza viruses have had some genetic material of avian origin. Since 1996, a strain of highly pathogenic avian influenza (HPAI) virus, H5N1, has caused infection in wild birds, losses to poultry farms in Eurasia and North Africa, and led to the deaths of several hundred people. Spread of the H5N1 virus and other influenza strains from China was likely facilitated by migratory birds. In December 2014, HPAI was detected in poultry in Canada and migratory birds in the United States. Since then, HPAI viruses have spread to large parts of the United States and will likely continue to spread through migratory bird flyways and other mechanisms throughout North America. In the United States, HPAI viruses have severely affected the poultry industry with millions of domestic birds dead or culled. These strains of HPAI are not known to cause disease in humans; however, the Centers for Disease Control and Prevention (CDC) advise caution when in close contact with infected birds. Experts agree that HPAI strains currently circulating in wild birds of North America will likely persist for the next few years. This unprecedented situation presents risks to the poultry industry, natural resource management, and potentially human health. Scientific knowledge and decision support tools are urgently needed to understand factors affecting the persistence

Avian malaria in a boreal resident species: long-term temporal variability, and increased prevalence in birds with avian keratin disorder

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Wilkinson, Laura C.; Handel, Colleen M.; Van Hemert, Caroline R.; Loiseau, Claire; Sehgal, Ravinder N. M.

2016-01-01

The prevalence of vector-borne parasitic diseases is widely influenced by biological and ecological factors. Environmental conditions such as temperature and precipitation can have a marked effect on haemosporidian parasites (Plasmodium spp.) that cause malaria and those that cause other malaria-like diseases in birds. However, there have been few long-term studies monitoring haemosporidian infections in birds in northern latitudes, where weather conditions can be highly variable and the effects of climate change are becoming more pronounced. We used molecular methods to screen more than 2,000 blood samples collected from black-capped chickadees (Poecile atricapillus), a resident passerine bird. Samples were collected over a 10 year period, mostly during the non-breeding season, at seven sites in Alaska, USA. We tested for associations between Plasmodium prevalence and local environmental conditions including temperature, precipitation, site, year and season. We also evaluated the relationship between parasite prevalence and individual host factors of age, sex and presence or absence of avian keratin disorder. This disease, which causes accelerated keratin growth in the beak, provided a natural study system in which to test the interaction between disease state and malaria prevalence. Prevalence of Plasmodium infection varied by year, site, age and individual disease status but there was no support for an effect of sex or seasonal period. Significantly, birds with avian keratin disorder were 2.6 times more likely to be infected by Plasmodium than birds without the disorder. Interannual variation in the prevalence of Plasmodium infection at different sites was positively correlated with summer temperatures at the local but not statewide scale. Sequence analysis of the parasite cytochrome b gene revealed a single Plasmodiumspp. lineage, P43. Our results demonstrate associations between prevalence of avian malaria and a variety of biological and

Immune Responses of Chickens Infected with Wild Bird-Origin H5N6 Avian Influenza Virus

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Shimin Gao

2017-06-01

Full Text Available Since April 2014, new infections of H5N6 avian influenza virus (AIV in humans and domestic poultry have caused considerable economic losses in the poultry industry and posed an enormous threat to human health worldwide. In previous research using gene sequence and phylogenetic analysis, we reported that H5N6 AIV isolated in February 2015 (ZH283 in Pallas’s sandgrouse was highly similar to that isolated in a human in December 2015 (A/Guangdong/ZQ874/2015, whereas a virus (i.e., SW8 isolated in oriental magpie-robin in 2014 was highly similar to that of A/chicken/Dongguan/2690/2013 (H5N6. However, the pathogenicity, transmissibility, and host immune-related response of chickens infected by those wild bird-origin H5N6 AIVs remain unknown. In response, we examined the viral distribution and mRNA expression profiles of immune-related genes in chickens infected with both viruses. Results showed that the H5N6 AIVs were highly pathogenic to chickens and caused not only systemic infection in multiple tissues, but also 100% mortality within 3–5 days post-infection. Additionally, ZH283 efficiently replicated in all tested tissues and transmitted among chickens more rapidly than SW8. Moreover, quantitative real-time polymerase chain reaction analysis showed that following infection with H5N6, AIVs immune-related genes remained active in a tissue-dependent manner, as well as that ZH283 induced mRNA expression profiles such as TLR3, TLR7, IL-6, TNF-α, IL-1β, IL-10, IL-8, and MHC-II to a greater extent than SW8 in the tested tissues of infected chickens. Altogether, our findings help to illuminate the pathogenesis and immunologic mechanisms of H5N6 AIVs in chickens.

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.

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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. Copyright © 2010 Elsevier B.V. All rights reserved.

Co-infection of turkeys with Escherichia coli (O78) and H6N1 avian influenza virus.

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Umar, Sajid; Delverdier, Maxence; Delpont, Mattias; Belkasmi, Sakhia F Z; Teillaud, Angélique; Bleuart, Céline; Pardo, Isabelle; El Houadfi, Mohammed; Guérin, Jean-Luc; Ducatez, Mariette F

2018-03-28

Respiratory diseases are responsible for major economic losses in poultry farms. While in most cases a single pathogen is not alone responsible for the clinical outcome, the impact of co-infections is not well known, especially in turkeys. The purpose of this study was to assess the possible synergism between Escherichia coli (O78) and low pathogenic avian influenza virus (LPAIV, H6N1), in the turkey model. Four-week-old commercial turkeys were inoculated with either H6N1, O78 or both agents simultaneously or three days apart. We have established an experimental infection model of turkeys using aerosolization that better mimics field infections. Birds were observed clinically and swabbed on a daily basis. Necropsies were performed at 4 and 14 days post single or dual inoculation and followed by histological and immunohistochemical analyses. Combined LPAIV/E. coli infections resulted in more severe clinical signs, were associated with higher mortality and respiratory organ lesions (mucous or fibrinous exudative material in lungs and air sacs), in comparison with the groups given single infections (P  0.05) respiratory signs were observed in turkeys of the E. coli followed by H6N1 inoculated group. Microscopic lesions and immunohistochemical staining supported clinical and macroscopic findings. Efficient virus and bacteria replication was observed in all inoculated groups. E. coli and H6N1 thus exercise an additive or synergistic pathogenic effect in the reproduction of respiratory disease.

Experimental co-infections of domestic ducks with a virulent Newcastle disease virus and low or highly pathogenic avian influenza viruses.

Science.gov (United States)

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

2015-05-15

Infections with avian influenza viruses (AIV) of low and high pathogenicity (LP and HP) and Newcastle disease virus (NDV) are commonly reported in domestic ducks in many parts of the world. However, it is not clear if co-infections with these viruses affect the severity of the diseases they produce, the amount of virus shed, and transmission of the viruses. In this study we infected domestic ducks with a virulent NDV virus (vNDV) and either a LPAIV or a HPAIV by giving the viruses individually, simultaneously, or sequentially two days apart. No clinical signs were observed in ducks infected or co-infected with vNDV and LPAIV, but co-infection decreased the number of ducks shedding vNDV and the amount of virus shed (Pducks inoculated with only LPAIV compared to ducks co-infected with vNDV. Ducks that received the HPAIV with the vNDV simultaneously survived fewer days (Pducks that received the vNDV two days before the HPAIV. Co-infection also reduced transmission of vNDV to naïve contact ducks housed with the inoculated ducks. In conclusion, domestic ducks can become co-infected with vNDV and LPAIV with no effect on clinical signs but with reduction of virus shedding and transmission. These findings indicate that infection with one virus can interfere with replication of another, modifying the pathogenesis and transmission of the viruses. Published by Elsevier B.V.

Feral Swine in the United States Have Been Exposed to both Avian and Swine Influenza A Viruses.

Science.gov (United States)

Martin, Brigitte E; Sun, Hailiang; Carrel, Margaret; Cunningham, Fred L; Baroch, John A; Hanson-Dorr, Katie C; Young, Sean G; Schmit, Brandon; Nolting, Jacqueline M; Yoon, Kyoung-Jin; Lutman, Mark W; Pedersen, Kerri; Lager, Kelly; Bowman, Andrew S; Slemons, Richard D; Smith, David R; DeLiberto, Thomas; Wan, Xiu-Feng

2017-10-01

Influenza A viruses (IAVs) in swine can cause sporadic infections and pandemic outbreaks among humans, but how avian IAV emerges in swine is still unclear. Unlike domestic swine, feral swine are free ranging and have many opportunities for IAV exposure through contacts with various habitats and animals, including migratory waterfowl, a natural reservoir for IAVs. During the period from 2010 to 2013, 8,239 serum samples were collected from feral swine across 35 U.S. states and tested against 45 contemporary antigenic variants of avian, swine, and human IAVs; of these, 406 (4.9%) samples were IAV antibody positive. Among 294 serum samples selected for antigenic characterization, 271 cross-reacted with ≥1 tested virus, whereas the other 23 did not cross-react with any tested virus. Of the 271 IAV-positive samples, 236 cross-reacted with swine IAVs, 1 with avian IAVs, and 16 with avian and swine IAVs, indicating that feral swine had been exposed to both swine and avian IAVs but predominantly to swine IAVs. Our findings suggest that feral swine could potentially be infected with both avian and swine IAVs, generating novel IAVs by hosting and reassorting IAVs from wild birds and domestic swine and facilitating adaptation of avian IAVs to other hosts, including humans, before their spillover. Continued surveillance to monitor the distribution and antigenic diversities of IAVs in feral swine is necessary to increase our understanding of the natural history of IAVs. IMPORTANCE There are more than 5 million feral swine distributed across at least 35 states in the United States. In contrast to domestic swine, feral swine are free ranging and have unique opportunities for contact with wildlife, livestock, and their habitats. Our serological results indicate that feral swine in the United States have been exposed to influenza A viruses (IAVs) consistent with those found in both domestic swine and wild birds, with the predominant infections consisting of swine-adapted IAVs

Captive-bred neotropical birds diagnosed with Cryptosporidium Avian genotype III.

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Silva Novaes, Ricardo; Pires, Marcus Sandes; Sudré, Adriana Pittella; Bergamo do Bomfim, Teresa Cristina

2018-02-01

Currently, there are only three valid species of Cryptosporidium infecting avian hosts, namely, Cryptosporidium meleagridis, Cryptosporidium baileyi, Cryptosporidium galli and Cryptosporidium avium in addition to 12 genotypes of unknown species status. The objectives of this study were to microscopically diagnose the presence of Cryptosporidium in birds from a commercial aviary located in Rio de Janeiro, Brazil; genotypically characterize species and/or genotypes of genus Cryptosporidum; and conduct sequencing and phylogenetic analyses to compare the obtained DNA sequences with those deposited in GenBank. A total of 85 fecal samples were collected from wild captive-bred birds: 48 of family Psittacidae and 37 of family Ramphastidae. Initially, a search for the presence of Cryptosporidium sp. oocysts was conducted using the centrifugal-flotation in saturated sugar solution technique, after that, the collected samples were analyzed microscopically. Cryptosporidium infections were only detected in 24.32% of samples belonging to the family Ramphastidae. DNA was extracted from positive samples and molecular diagnostics was applied targeting the 18S rRNA gene, followed by sequencing and phylogenetic analysis. The Cryptosporidium Avian genotype III was diagnosed in this study more closely related to the gastric species. This is the first record of Cryptosporidium Avian genotype III in order Piciformes and family Ramphastidae, where three host species (Ramphastus toco, Ramphastus tucanus, and Pteroglossus bailloni) were positive for the etiologic agent. Based on the molecular data obtained, these wild birds raised in captivity do not represent a source of human cryptosporidiosis, considering that Cryptosporidium Avian genotype III does not constitute a zoonosis. Copyright © 2017. Published by Elsevier B.V.

Transmission and reassortment of avian influenza viruses at the Asian-North American interface.

Science.gov (United States)

Ramey, Andrew M; Pearce, John M; Ely, Craig R; Guy, Lisa M Sheffield; Irons, David B; Derksen, Dirk V; Ip, Hon S

2010-10-25

Twenty avian influenza viruses were isolated from seven wild migratory bird species sampled at St. Lawrence Island, Alaska. We tested predictions based on previous phylogenetic analyses of avian influenza viruses that support spatially dependent trans-hemispheric gene flow and frequent interspecies transmission at a location situated at the Asian-North American interface. Through the application of phylogenetic and genotypic approaches, our data support functional dilution by distance of trans-hemispheric reassortants and interspecific virus transmission. Our study confirms infection of divergent avian taxa with nearly identical avian influenza strains in the wild. Findings also suggest that H16N3 viruses may contain gene segments with unique phylogenetic positions and that further investigation of how host specificity may impact transmission of H13 and H16 viruses is warranted. Copyright © 2010. Published by Elsevier Inc.

A polyclonal antibody against extracellular loops 1 of chNHE1 blocks avian leukosis virus subgroup J infection.

Science.gov (United States)

Meng, Wei; Zhou, Defang; Li, Chengui; Wang, Guihua; Huang, Libo; Cheng, Ziqiang

2018-05-02

Avian leukosis virus subgroup J (ALV-J), an oncogenic retrovirus, induces myelocytomas and other various tumors, leading to great economical losses in poultry industry. It is a great challenge to develop effective preventive methods for ALV-J control due to its antigenic variations in the variable regions of envelope. In present study, we generated a mouse polyclonal antibody targeting the first extracellular loop (ECL1) of chicken Na + /H + exchanger isoform 1 (chNHE1), the receptor of ALV-J, to block ALV-J infection in vitro and in vivo. In ALV-J infected DF-1 cells, chNHE1 expression and the intracellular pH (pHi) were up-regulated with "wave" pattern, indicating that the disequilibrium of ALV-J infected cells associated with chNHE1. Next, we validated that ALV-J infection was significantly blocked with time dependent after treating with anti-ECL1 antibody and accordingly the pHi value were recovered, indicating the blockage of ALV-J infection did not affect Na + /H + exchange. Furthermore, in anti-ECL1 antibody treatment chickens that infected by ALV-J, weight gain and immune organs were recovered, and viral loads were significantly decreased, and the tissue injury and inflammation were reduced significantly from 21 to 35 days of age. The study demonstrated that anti-ECL1 antibody effectively blocks ALV-J infection without affecting Na + /H + exchange, and sheds light on a novel strategy for retroviruses control. Copyright © 2018 Elsevier Ltd. All rights reserved.

Avian Influenza Virus (H5N1): a Threat to Human Health

OpenAIRE

Peiris, J. S. Malik; de Jong, Menno D.; Guan, Yi

2007-01-01

Pandemic influenza virus has its origins in avian influenza viruses. The highly pathogenic avian influenza virus subtype H5N1 is already panzootic in poultry, with attendant economic consequences. It continues to cross species barriers to infect humans and other mammals, often with fatal outcomes. Therefore, H5N1 virus has rightly received attention as a potential pandemic threat. However, it is noted that the pandemics of 1957 and 1968 did not arise from highly pathogenic influenza viruses, ...

Avian influenza virus

Science.gov (United States)

Avian influenza virus (AIV) is type A influenza that is adapted to avian host species. Although the virus can be isolated from numerous avian species, the natural host reservoir species are dabbling ducks, shorebirds and gulls. Domestic poultry species (poultry being defined as birds that are rais...

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.

Signal Immune Reactions of Macrophages Differentiated from THP-1 Monocytes to Infection with Pandemic H1N1PDM09 Virus and H5N2 and H9N2 Avian Influenza A Virus.

Science.gov (United States)

Sokolova, T M; Poloskov, V V; Shuvalov, A N; Rudneva, I A; Timofeeva, T A

2018-03-01

In culture of THP-1 cells differentiated into macrophages with PMA (THP-PMA macrophages) infected with influenza viruses of subtypes H1, H5 and H9, we measured the expression of TLR7 and RIG1 receptor genes, sensors of viral RNA and ribonucleoprotein, and the levels of production of inflammatory cytokines IL-1β, TNFα, IL-10, and IFNα. The sensitivity and inflammatory response of THP-PMA macrophages to pandemic influenza A virus H1N1pdm09 and avian influenza H5N2 and H9N2 viruses correlate with the intracellular level of their viral RNA and activation of the RIG1 gene. Abortive infection is accompanied by intensive macrophage secretion of TNFα, IL-1β, and toxic factors inducing cell death. Activity of endosomal TLR7 receptor gene changed insignificantly in 24 h after infection and significantly decreased in 48 and 72 h under the action of H5N2 and H9N2, which correlated with manifestation of the cytopathogenic effect of these viruses. H5N2 and H9N2 avian viruses in THP-PMA macrophages are strong activators of the expression of the gene of the cytoplasmic RIG1 receptor 24 and 48 h after infection, and the pandemic virus H1N1pdm09 is a weak stimulator of RIG1 gene. Avian influenza H5N2 and H9N2 viruses are released by rapid induction of the inflammatory response in macrophages. At the late stages of infection, we observed a minor increase in IL-10 secretion in macrophages and, probably, the polarization of a part of the population in type M2. The studied influenza A viruses are weak inductors of IFN in THP-PMA macrophages. In the culture medium of THP-PMA macrophages infected with H9N2 and H5N2 viruses, MTT test revealed high levels of toxic factors causing the death of Caco-2 cells. In contrast to avian viruses, pandemic virus H1N1pdm09 did not induce production of toxic factors.

Pathology of natural infections by H5N1 highly pathogenic avian influenza virus in mute (Cygnus olor) and whooper (Cygnus cygnus) swans.

Science.gov (United States)

Teifke, J P; Klopfleisch, R; Globig, A; Starick, E; Hoffmann, B; Wolf, P U; Beer, M; Mettenleiter, T C; Harder, T C

2007-03-01

Mortality in wild aquatic birds due to infection with highly pathogenic avian influenza viruses (HPAIV) is a rare event. During the recent outbreak of highly pathogenic avian influenza in Germany, mortality due to H5N1 HPAIV was observed among mute and whooper swans as part of a rapid spread of this virus. In contrast to earlier reports, swans appeared to be highly susceptible and represented the mainly affected species. We report gross and histopathology and distribution of influenza virus antigen in mute and whooper swans that died after natural infection with H5N1 HPAIV. At necropsy, the most reliable lesions were multifocal hemorrhagic necrosis in the pancreas, pulmonary congestion and edema, and subepicardial hemorrhages. Major histologic lesions were acute pancreatic necrosis, multifocal necrotizing hepatitis, and lymphoplasmacytic encephalitis with neuronal necrosis. Adrenals displayed consistently scattered cortical and medullary necrosis. In spleen and Peyer's patches, mild lymphocyte necrosis was present. Immunohistochemical demonstration of HPAIV nucleoprotein in pancreas, adrenals, liver, and brain was strongly consistent with histologic lesions. In the brain, a large number of neurons and glial cells, especially Purkinje cells, showed immunostaining. Occasionally, ependymal cells of the spinal cord were also positive. In the lungs, influenza virus antigen was identified in a few endothelial cells but not within pneumocytes. The infection of the central nervous system supports the view that the neurotropism of H5N1 HPAIV leads to nervous disturbances with loss of orientation. More investigations are necessary to clarify the mechanisms of the final circulatory failure, lung edema, and rapid death of the swans.

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.C.; Meteyer, C.; Nashold, Sean W.; Teslaa, Joshua 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.

Novel Polymerase Gene Mutations for Human Adaptation in Clinical Isolates of Avian H5N1 Influenza Viruses.

Directory of Open Access Journals (Sweden)

Yasuha Arai

2016-04-01

Full Text Available A major determinant in the change of the avian influenza virus host range to humans is the E627K substitution in the PB2 polymerase protein. However, the polymerase activity of avian influenza viruses with a single PB2-E627K mutation is still lower than that of seasonal human influenza viruses, implying that avian viruses require polymerase mutations in addition to PB2-627K for human adaptation. Here, we used a database search of H5N1 clade 2.2.1 virus sequences with the PB2-627K mutation to identify other polymerase adaptation mutations that have been selected in infected patients. Several of the mutations identified acted cooperatively with PB2-627K to increase viral growth in human airway epithelial cells and mouse lungs. These mutations were in multiple domains of the polymerase complex other than the PB2-627 domain, highlighting a complicated avian-to-human adaptation pathway of avian influenza viruses. Thus, H5N1 viruses could rapidly acquire multiple polymerase mutations that function cooperatively with PB2-627K in infected patients for optimal human adaptation.

Planning for avian flu disruptions on global operations: a DMAIC case study.

Science.gov (United States)

Kumar, Sameer

2012-01-01

The author aims to assess the spread of avian flu, its impact on businesses operating in the USA and overseas, and the measures required for corporate preparedness. Six Sigma DMAIC process is used to analyze avian flu's impact and how an epidemic could affect large US business operations worldwide. Wal-Mart and Dell Computers were chosen as one specializes in retail and the other manufacturing. The study identifies avian flu pandemic risks including failure modes on Wal-Mart and Dell Computers global operations. It reveals the factors that reinforce avian-flu pandemic's negative impact on company global supply chains. It also uncovers factors that balance avian-flu pandemic's impact on their global supply chains. Avian flu and its irregularity affect the research outcomes because its spread could fluctuate based on so many factors that could come into play. Further, the potential cost to manufacturers and other supply chain partners is relatively unknown. As a relatively new phenomenon, quantitative data were not available to determine immediate costs. In this decade, the avian influenza H5N1 virus has killed millions of poultry in Asia, Europe and Africa. This flu strain can infect and kill humans who come into contact with this virus. An avian influenza H5N1 outbreak could lead to a devastating effect on global food supply, business services and business operations. The study provides guidance on what global business operation managers can do to prepare for such events, as well as how avian flu progression to a pandemic can disrupt such operations. This study raises awareness about avian flu's impact on businesses and humans and also highlights the need to create contingency plans for corporate preparedness to avoid incurring losses.

Avian Influenza Virus Infection of Immortalized Human Respiratory Epithelial Cells Depends upon a Delicate Balance between Hemagglutinin Acid Stability and Endosomal pH.

Science.gov (United States)

Daidoji, Tomo; Watanabe, Yohei; Ibrahim, Madiha S; Yasugi, Mayo; Maruyama, Hisataka; Masuda, Taisuke; Arai, Fumihito; Ohba, Tomoyuki; Honda, Ayae; Ikuta, Kazuyoshi; Nakaya, Takaaki

2015-04-24

The highly pathogenic avian influenza (AI) virus, H5N1, is a serious threat to public health worldwide. Both the currently circulating H5N1 and previously circulating AI viruses recognize avian-type receptors; however, only the H5N1 is highly infectious and virulent in humans. The mechanism(s) underlying this difference in infectivity remains unclear. The aim of this study was to clarify the mechanisms responsible for the difference in infectivity between the current and previously circulating strains. Primary human small airway epithelial cells (SAECs) were transformed with the SV40 large T-antigen to establish a series of clones (SAEC-Ts). These clones were then used to test the infectivity of AI strains. Human SAEC-Ts could be broadly categorized into two different types based on their susceptibility (high or low) to the viruses. SAEC-T clones were poorly susceptible to previously circulating AI but were completely susceptible to the currently circulating H5N1. The hemagglutinin (HA) of the current H5N1 virus showed greater membrane fusion activity at higher pH levels than that of previous AI viruses, resulting in broader cell tropism. Moreover, the endosomal pH was lower in high susceptibility SAEC-T clones than that in low susceptibility SAEC-T clones. Taken together, the results of this study suggest that the infectivity of AI viruses, including H5N1, depends upon a delicate balance between the acid sensitivity of the viral HA and the pH within the endosomes of the target cell. Thus, one of the mechanisms underlying H5N1 pathogenesis in humans relies on its ability to fuse efficiently with the endosomes in human airway epithelial cells. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Complete avian malaria parasite genomes reveal features associated with lineage-specific evolution in birds and mammals

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Böhme, Ulrike; Otto, Thomas D.; Cotton, James A.; Steinbiss, Sascha; Sanders, Mandy; Oyola, Samuel O.; Nicot, Antoine; Gandon, Sylvain; Patra, Kailash P.; Herd, Colin; Bushell, Ellen; Modrzynska, Katarzyna K.; Billker, Oliver; Vinetz, Joseph M.; Rivero, Ana; Newbold, Chris I.; Berriman, Matthew

2018-01-01

Avian malaria parasites are prevalent around the world and infect a wide diversity of bird species. Here, we report the sequencing and analysis of high-quality draft genome sequences for two avian malaria species, Plasmodium relictum and Plasmodium gallinaceum. We identify 50 genes that are specific to avian malaria, located in an otherwise conserved core of the genome that shares gene synteny with all other sequenced malaria genomes. Phylogenetic analysis suggests that the avian malaria species form an outgroup to the mammalian Plasmodium species, and using amino acid divergence between species, we estimate the avian- and mammalian-infective lineages diverged in the order of 10 million years ago. Consistent with their phylogenetic position, we identify orthologs of genes that had previously appeared to be restricted to the clades of parasites containing Plasmodium falciparum and Plasmodium vivax, the species with the greatest impact on human health. From these orthologs, we explore differential diversifying selection across the genus and show that the avian lineage is remarkable in the extent to which invasion-related genes are evolving. The subtelomeres of the P. relictum and P. gallinaceum genomes contain several novel gene families, including an expanded surf multigene family. We also identify an expansion of reticulocyte binding protein homologs in P. relictum, and within these proteins, we detect distinct regions that are specific to nonhuman primate, humans, rodent, and avian hosts. For the first time in the Plasmodium lineage, we find evidence of transposable elements, including several hundred fragments of LTR-retrotransposons in both species and an apparently complete LTR-retrotransposon in the genome of P. gallinaceum. PMID:29500236

[Epidemiology of human infection with avian influenza A(H7N9) virus in China, 2013-2017].

Science.gov (United States)

Han, D D; Han, C X; Li, L Y; Wang, M; Yang, J H; Li, M

2018-01-10

Objective: To understand the epidemiological characteristics of human infection with avian influenza A (H7N9) virus in China, and provide evidence for the prevention and control of human infection with H7N9 virus. Methods: The published incidence data of human infection with H7N9 virus in China from March 2013 to April 2017 were collected. Excel 2007 software was used to perform the analysis. The characteristics of distribution of the disease, exposure history, cluster of the disease were described. Results: By the end of April 2017, a total of 1 416 cases of human infection with H7N9 virus were confirmed in China, including 559 deaths, the case fatality rate was 39.5%. In 2016, the case number was lowest (127 cases), with the highest fatality rate (57.5%). The first three provinces with high case numbers were Zhejiang, Guangdong and Jiangsu. The median age of the cases was 55 years and the male to female ratio was 2.3∶1. Up to 66% of cases had clear live poultry exposure history before illness onset, 31% of cases had unknown exposure history and only 3% of the cases had no live poultry exposure history. There were 35 household clusters (5 in 2013, 9 in 2014, 6 in 2015, 5 in 2016, 10 in 2017), which involved 72 cases, accounting for 5% of the total cases. Conclusions: The epidemic of human infection with H7N9 virus in China during 2013-2017 had obvious seasonality and spatial distribution. There was limited family clustering. Infection cases were mostly related to poultry contact.

Economic epidemiology of avian influenza on smallholder poultry farms☆

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Boni, Maciej F.; Galvani, Alison P.; Wickelgren, Abraham L.; Malani, Anup

2013-01-01

Highly pathogenic avian influenza (HPAI) is often controlled through culling of poultry. Compensating farmers for culled chickens or ducks facilitates effective culling and control of HPAI. However, ensuing price shifts can create incentives that alter the disease dynamics of HPAI. Farmers control certain aspects of the dynamics by setting a farm size, implementing infection control measures, and determining the age at which poultry are sent to market. Their decisions can be influenced by the market price of poultry which can, in turn, be set by policy makers during an HPAI outbreak. Here, we integrate these economic considerations into an epidemiological model in which epidemiological parameters are determined by an outside agent (the farmer) to maximize profit from poultry sales. Our model exhibits a diversity of behaviors which are sensitive to (i) the ability to identify infected poultry, (ii) the average price of infected poultry, (iii) the basic reproductive number of avian influenza, (iv) the effect of culling on the market price of poultry, (v) the effect of market price on farm size, and (vi) the effect of poultry density on disease transmission. We find that under certain market and epidemiological conditions, culling can increase farm size and the total number of HPAI infections. Our model helps to inform the optimization of public health outcomes that best weigh the balance between public health risk and beneficial economic outcomes for farmers. PMID:24161559

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.

Swine influenza virus: zoonotic potential and vaccination strategies for the control of avian and swine influenzas.

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Thacker, Eileen; Janke, Bruce

2008-02-15

Influenza viruses are able to infect humans, swine, and avian species, and swine have long been considered a potential source of new influenza viruses that can infect humans. Swine have receptors to which both avian and mammalian influenza viruses bind, which increases the potential for viruses to exchange genetic sequences and produce new reassortant viruses in swine. A number of genetically diverse viruses are circulating in swine herds throughout the world and are a major cause of concern to the swine industry. Control of swine influenza is primarily through the vaccination of sows, to protect young pigs through maternally derived antibodies. However, influenza viruses continue to circulate in pigs after the decay of maternal antibodies, providing a continuing source of virus on a herd basis. Measures to control avian influenza in commercial poultry operations are dictated by the virulence of the virus. Detection of a highly pathogenic avian influenza (HPAI) virus results in immediate elimination of the flock. Low-pathogenic avian influenza viruses are controlled through vaccination, which is done primarily in turkey flocks. Maintenance of the current HPAI virus-free status of poultry in the United States is through constant surveillance of poultry flocks. Although current influenza vaccines for poultry and swine are inactivated and adjuvanted, ongoing research into the development of newer vaccines, such as DNA, live-virus, or vectored vaccines, is being done. Control of influenza virus infection in poultry and swine is critical to the reduction of potential cross-species adaptation and spread of influenza viruses, which will minimize the risk of animals being the source of the next pandemic.

[Summary of Guangdong provincial seminar on avian influenza and influenza].

Science.gov (United States)

Yu, Shou-yi; Chen, Qing; Hu, Gui-fang

2005-12-01

On 8th November 2005, an academic seminar on avian influenza and influenza in Guangdong Province was held by Guangdong Society of Tropical Medicine and the Epidemiology Committee of the Guangdong Preventive Medicine Society in Southern Medical University, addressing the current problems in epidemics of avian influenza. The specialists attending the conference arrived at the common consideration that at present, the avian influenza virus H5N1 has not the capacity to trigger an pandemic in human population, but scattered cases had been reported to increase the suspicions of H5N1 virus transmission between humans. Due attention should be paid to the tendency of expansion of the host range and epidemic area, and the possibility of disastrous influenza pandemic among human populations persists, for which rational consideration is called for, and the role of specialists should be fully recognized who are endeavoring to examine the possible scale of influenza occurrence and devise strategy to deal with the epidemic in Guangdong province according to the practical situation in China. Increased funds and investment in scientific research on avian influenza is urged for influenza prediction and surveillance, rapid and early diagnostic assays, understanding of virus variation, mechanism of H5N1 virus adaptation to human hosts, effective medicines and vaccines for prevention and therapy of avian influenza. Laboratory bio-safety control should be enforced to prevent infections originated from laboratories. The specialists appeal that the media report the news objectively and issue the public warnings against avian influenza after consulting specialists, so as to avoid unnecessary social panic.

First evidence of avian metapneumovirus subtype A infection in turkeys in Egypt.

Science.gov (United States)

Abdel-Azeem, Abdel-Azeem Sayed; Franzo, Giovanni; Dalle Zotte, Antonella; Drigo, Michele; Catelli, Elena; Lupini, Caterina; Martini, Marco; Cecchinato, Mattia

2014-08-01

Although avian metapneumovirus (aMPV) infection has been reported in most regions of the world, to date, only subtype B has been detected in Egypt. At the end of November 2013, dry oropharyngeal swabs were collected during an outbreak of respiratory diseases in a free-range, multi-age turkey dealer farm in Northern Upper Egypt. The clinical signs that appeared when turkeys were 3 weeks-old were characterized by ocular and nasal discharge and swelling of sinuses. aMPV of subtype A was detected by real-time reverse transcription-polymerase chain reaction. In order to confirm the results and obtain more information on the molecular characteristics of the virus, F and G protein genes were partially sequenced and compared with previously published sequences deposited in GenBank by using BLAST. Subtype of the strain was confirmed by sequencing of partial F and G protein genes. The highest percentages of identity were observed when G sequence of the Egyptian strain was compared with the sequence of an aMPV-A isolated in Nigeria (96.4 %) and when the F sequence was compared with strains isolated respectively in Italy and in UK (97.1 %). Moreover, the alignment of the sequences with commercial subtype A vaccine or vaccine-derived strains showed differences in the Egyptian strain that indicate its probable field origin. The detection of aMPV in the investigated turkey flock highlights some relevant epidemiological issues regarding the role that multi-age farms and dealers may play in perpetuating aMPV infection within and among farms. To our knowledge, this is the first report of aMPV subtype A in Egypt.

Avian influenza virus infection in apparently healthy domestic birds in Sokoto, Nigeria

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Innocent Okwundu Nwankwo

2012-09-01

Full Text Available The study was conducted among apparently healthy birds brought from different local government areas, neighbouring states and across international boundaries to the Sokoto central live bird market between October 2008 and March 2009. Tracheal and cloacal swabs were collected from 221 apparently healthy birds comprising 182 chickens, 3 turkeys, 11 guineafowl, 17 ducks and 8 pigeons. These samples were analysed using nested polymerase chain reaction (nPCR to check for the presence of avian influenza virus. An overall prevalence of 1.4% (3 positive cases was detected with two cases observed in chickens and one in a pigeon. The findings indicate the circulation of avian influenza in the study area. This raises concern for human and animal health due to zoonotic and economic implications of this virus.

The effect of age on the pathogenesis of a highly pathogenic avian influenza (HPAI) H5N1 virus in Pekin ducks (Anas platyrhynchos) infected experimentally

OpenAIRE

L?ndt, Brandon Z.; N??ez, Alejandro.; Banks, Jill; Alexander, Dennis J.; Russell, Christine; Richard? L?ndt, Angela C.; Brown, Ian H.

2009-01-01

Background? Highly pathogenic avian influenza (HPAI) H5N1 viruses have recently displayed increased virulence for wild waterfowl. Objectives? To study the effect of host age on the shedding and tissue dissemination of a HPAI H5N1 virus in infected Pekin ducks. Methods? Pekin ducks in two age?matched groups (n?=?18), 8 and 12?weeks old (wo) were each infected with 106 EID50/0?1?ml of HPAI A/turkey/Turkey/1/05 (H5N1, clade 2?2). Each day for 5?days, birds were monitored clinically, and cloacal ...

Avian influenza A virus subtype H5N2 in a red-lored Amazon parrot.

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Hawkins, Michelle G; Crossley, Beate M; Osofsky, Anna; Webby, Richard J; Lee, Chang-Won; Suarez, David L; Hietala, Sharon K

2006-01-15

A 3-month-old red-lored Amazon parrot (Amazona autumnalis autumnalis) was evaluated for severe lethargy. Avian influenza virus hemagglutinin subtype H5N2 with low pathogenicity was characterized by virus isolation, real-time reverse transcriptase PCR assay, chicken intravenous pathogenicity index, and reference sera. The virus was also determined to be closely related to a virus lineage that had been reported only in Mexico and Central America. The chick was admitted to the hospital and placed in quarantine. Supportive care treatment was administered. Although detection of H5 avian influenza virus in birds in the United States typically results in euthanasia of infected birds, an alternative strategy with strict quarantine measures and repeated diagnostic testing was used. The chick recovered from the initial clinical signs after 4 days and was released from quarantine 9 weeks after initial evaluation after 2 consecutive negative virus isolation and real-time reverse transcriptase PCR assay results. To the authors' knowledge, this is the first report of H5N2 avian influenza A virus isolated from a psittacine bird and represents the first introduction of this virus into the United States, most likely by illegal importation of psittacine birds. Avian influenza A virus should be considered as a differential diagnosis for clinical signs of gastrointestinal tract disease in psittacine birds, especially in birds with an unknown history of origin. Although infection with avian influenza virus subtype H5 is reportable, destruction of birds is not always required.

Infectious bronchitis corona virus establishes productive infection in avian macrophages interfering with selected antimicrobial functions.

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Aruna Amarasinghe

Full Text Available Infectious bronchitis virus (IBV causes respiratory disease leading to loss of egg and meat production in chickens. Although it is known that macrophage numbers are elevated in the respiratory tract of IBV infected chickens, the role played by macrophages in IBV infection, particularly as a target cell for viral replication, is unknown. In this study, first, we investigated the ability of IBV to establish productive replication in macrophages in lungs and trachea in vivo and in macrophage cell cultures in vitro using two pathogenic IBV strains. Using a double immunofluorescent technique, we observed that both IBV Massachusetts-type 41 (M41 and Connecticut A5968 (Conn A5968 strains replicate in avian macrophages at a low level in vivo. This in vivo observation was substantiated by demonstrating IBV antigens in macrophages following in vitro IBV infection. Further, IBV productive infection in macrophages was confirmed by demonstrating corona viral particles in macrophages and IBV ribonucleic acid (RNA in culture supernatants. Evaluation of the functions of macrophages following infection of macrophages with IBV M41 and Conn A5968 strains revealed that the production of antimicrobial molecule, nitric oxide (NO is inhibited. It was also noted that replication of IBV M41 and Conn A5968 strains in macrophages does not interfere with the induction of type 1 IFN activity by macrophages. In conclusion, both M41 and Con A5968 IBV strains infect macrophages in vivo and in vitro resulting productive replications. During the replication of IBV in macrophages, their ability to produce NO can be affected without affecting the ability to induce type 1 IFN activity. Further studies are warranted to uncover the significance of macrophage infection of IBV in the pathogenesis of IBV infection in chickens.

Influence of Novel Highly Pathogenic Avian Influenza A (H5N1 Virus Infection on Migrating Whooper Swans Fecal Microbiota

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Na Zhao

2018-02-01

Full Text Available The migration of wild birds plays an important role in the transmission and spread of H5 highly pathogenic avian influenza (HPAI virus, posing a severe risk to animal and human health. Substantial evidence suggests that altered gut microbial community is implicated in the infection of respiratory influenza virus. However, the influence of H5N1 infection in gut microbiota of migratory birds remains unknown. In January 2015, a novel recombinant H5N1 virus emerged and killed about 100 migratory birds, mainly including whooper swans in Sanmenxia Reservoir Area of China. Here, we describe the first fecal microbiome diversity study of H5N1-infected migratory birds. By investigating the influence of H5N1 infection on fecal bacterial communities in infected and uninfected individuals, we found that H5N1 infection shaped the gut microbiota composition by a difference in the dominance of some genera, such as Aeromonas and Lactobacillus. We also found a decreased α diversity and increased β diversity in infectious individuals. Our results highlight that increases in changes in pathogen-containing gut communities occur when individuals become infected with H5N1. Our study may provide the first evidence that there are statistical association among H5N1 presence and fecal microbiota compositional shifts, and properties of the fecal microbiota may serve as the risk of gut-linked disease in migrates with H5N1 and further aggravate the disease transmission.

Influence of Novel Highly Pathogenic Avian Influenza A (H5N1) Virus Infection on Migrating Whooper Swans Fecal Microbiota.

Science.gov (United States)

Zhao, Na; Wang, Supen; Li, Hongyi; Liu, Shelan; Li, Meng; Luo, Jing; Su, Wen; He, Hongxuan

2018-01-01

The migration of wild birds plays an important role in the transmission and spread of H5 highly pathogenic avian influenza (HPAI) virus, posing a severe risk to animal and human health. Substantial evidence suggests that altered gut microbial community is implicated in the infection of respiratory influenza virus. However, the influence of H5N1 infection in gut microbiota of migratory birds remains unknown. In January 2015, a novel recombinant H5N1 virus emerged and killed about 100 migratory birds, mainly including whooper swans in Sanmenxia Reservoir Area of China. Here, we describe the first fecal microbiome diversity study of H5N1-infected migratory birds. By investigating the influence of H5N1 infection on fecal bacterial communities in infected and uninfected individuals, we found that H5N1 infection shaped the gut microbiota composition by a difference in the dominance of some genera, such as Aeromonas and Lactobacillus . We also found a decreased α diversity and increased β diversity in infectious individuals. Our results highlight that increases in changes in pathogen-containing gut communities occur when individuals become infected with H5N1. Our study may provide the first evidence that there are statistical association among H5N1 presence and fecal microbiota compositional shifts, and properties of the fecal microbiota may serve as the risk of gut-linked disease in migrates with H5N1 and further aggravate the disease transmission.

Outbreak of avian malaria associated to multiple species of Plasmodium in magellanic penguins undergoing rehabilitation in southern Brazil.

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Ralph Eric Thijl Vanstreels

Full Text Available Avian malaria is a mosquito-borne disease caused by Plasmodium spp. Avian plasmodia are recognized conservation-threatening pathogens due to their potential to cause severe epizootics when introduced to bird populations with which they did not co-evolve. Penguins are considered particularly susceptible, as outbreaks in captive populations will often lead to high morbidity and rapid mortality. We used a multidisciplinary approach to investigate an outbreak of avian malaria in 28 Magellanic penguins (Spheniscus magellanicus at a rehabilitation center during summer 2009 in Florianópolis, Brazil. Hemosporidian infections were identified by microscopic and molecular characterization in 64% (18/28 of the penguins, including Plasmodium (Haemamoeba tejerai, Plasmodium (Huffia elongatum, a Plasmodium (Haemamoeba sp. lineage closely related to Plasmodium cathemerium, and a Haemoproteus (Parahaemoproteus sp. lineage closely related to Haemoproteus syrnii. P. tejerai played a predominant role in the studied outbreak and was identified in 72% (13/18 of the hemosporidian-infected penguins, and in 89% (8/9 of the penguins that died, suggesting that this is a highly pathogenic parasite for penguins; a detailed description of tissue meronts and lesions is provided. Mixed infections were identified in three penguins, and involved P. elongatum and either P. tejerai or P. (Haemamoeba sp. that were compatible with P. tejerai but could not be confirmed. In total, 32% (9/28 penguins died over the course of 16 days despite oral treatment with chloroquine followed by sulfadiazine-trimethoprim. Hemosporidian infections were considered likely to have occurred during rehabilitation, probably from mosquitoes infected while feeding on local native birds, whereas penguin-mosquito-penguin transmission may have played a role in later stages of the outbreak. Considering the seasonality of the infection, rehabilitation centers would benefit from narrowing their efforts to

Effect of receptor binding domain mutations on receptor binding and transmissibility of avian influenza H5N1 viruses

DEFF Research Database (Denmark)

Maines, Taronna R; Chen, Li-Mei; Van Hoeven, Neal

2011-01-01

Although H5N1 influenza viruses have been responsible for hundreds of human infections, these avian influenza viruses have not fully adapted to the human host. The lack of sustained transmission in humans may be due, in part, to their avian-like receptor preference. Here, we have introduced recep...

Emergence of fatal avian influenza in New England harbor seals

Science.gov (United States)

Anthony, S.J.; St. Leger, J. A.; Pugliares, K.; Ip, Hon S.; Chan, J.M.; Carpenter, Z.W.; Navarrete-Macias, I.; Sanchez-Leon, M.; Saliki, J.T.; Pedersen, J.; Karesh, W.; Daszak, P.; Rabadan, R.; Rowles, T.; Lipkin, W.I.

2012-01-01

From September to December 2011, 162 New England harbor seals died in an outbreak of pneumonia. Sequence analysis of postmortem samples revealed the presence of an avian H3N8 influenza A virus, similar to a virus circulating in North American waterfowl since at least 2002 but with mutations that indicate recent adaption to mammalian hosts. These include a D701N mutation in the viral PB2 protein, previously reported in highly pathogenic H5N1 avian influenza viruses infecting people. Lectin staining and agglutination assays indicated the presence of the avian-preferred SAα-2,3 and mammalian SAα-2,6 receptors in seal respiratory tract, and the ability of the virus to agglutinate erythrocytes bearing either the SAα-2,3 or the SAα-2,6 receptor. The emergence of this A/harbor seal/Massachusetts/1/2011 virus may herald the appearance of an H3N8 influenza clade with potential for persistence and cross-species transmission.

Avian influenza virus risk assessment in falconry

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Lüschow Dörte

2011-04-01

Full Text Available Abstract Background There is a continuing threat of human infections with avian influenza viruses (AIV. In this regard falconers might be a potential risk group because they have close contact to their hunting birds (raptors such as falcons and hawks as well as their avian prey such as gulls and ducks. Both (hunting birds and prey birds seem to be highly susceptible to some AIV strains, especially H5N1. We therefore conducted a field study to investigate AIV infections in falconers, their falconry birds as well as prey birds. Findings During 2 hunting seasons (2006/2007 and 2007/2008 falconers took tracheal and cloacal swabs from 1080 prey birds that were captured by their falconry birds (n = 54 in Germany. AIV-RNA of subtypes H6, H9, or H13 was detected in swabs of 4.1% of gulls (n = 74 and 3.8% of ducks (n = 53 using RT-PCR. The remaining 953 sampled prey birds and all falconry birds were negative. Blood samples of the falconry birds tested negative for AIV specific antibodies. Serum samples from all 43 falconers reacted positive in influenza A virus-specific ELISA, but remained negative using microneutralisation test against subtypes H5 and H7 and haemagglutination inhibition test against subtypes H6, H9 and H13. Conclusion Although we were able to detect AIV-RNA in samples from prey birds, the corresponding falconry birds and falconers did not become infected. Currently falconers do not seem to carry a high risk for getting infected with AIV through handling their falconry birds and their prey.

Case-control study of risk factors for human infection with avian influenza A(H7N9) virus in Shanghai, China, 2013.

Science.gov (United States)

Li, J; Chen, J; Yang, G; Zheng, Y X; Mao, S H; Zhu, W P; Yu, X L; Gao, Y; Pan, Q C; Yuan, Z A

2015-07-01

The first human infection with avian influenza A(H7N9) virus was reported in Shanghai, China in March 2013. An additional 32 cases of human H7N9 infection were identified in the following months from March to April 2013 in Shanghai. Here we conducted a case-control study of the patients with H7N9 infection (n = 25) using controls matched by age, sex, and residence to determine risk factors for H7N9 infection. Our findings suggest that chronic disease and frequency of visiting a live poultry market (>10 times, or 1-9 times during the 2 weeks before illness onset) were likely to be significantly associated with H7N9 infection, with the odds ratios being 4.07 [95% confidence interval (CI) 1.32-12.56], 10.61 (95% CI 1.85-60.74), and 3.76 (95% CI 1.31-10.79), respectively. Effective strategies for live poultry market control should be reinforced and ongoing education of the public is warranted to promote behavioural changes that can help to eliminate direct or indirect contact with influenza A(H7N9) virus.

Avian colibacillosis: still many black holes.

Science.gov (United States)

Guabiraba, Rodrigo; Schouler, Catherine

2015-08-01

Avian pathogenic Escherichia coli (APEC) strains cause severe respiratory and systemic diseases, threatening food security and avian welfare worldwide. Intensification of poultry production and the quick expansion of free-range production systems will increase the incidence of colibacillosis through greater exposure of birds to pathogens and stress. Therapy is mainly based on antibiotherapy and current vaccines have poor efficacy. Serotyping remains the most frequently used diagnostic method, only allowing the identification of a limited number of APEC strains. Several studies have demonstrated that the most common virulence factors studied in APEC are all rarely present in the same isolate, showing that APEC strains constitute a heterogeneous group. Different isolates may harbor different associations of virulence factors, each one able to induce colibacillosis. Despite its economical relevance, pathogenesis of colibacillosis is poorly understood. Our knowledge on the host response to APEC is based on very descriptive studies, mostly restricted to bacteriological and histopathological analysis of infected organs such as lungs. Furthermore, only a small number of APEC isolates have been used in experimental studies. In the present review, we discuss current knowledge on APEC diversity and virulence, including host response to infection and the associated inflammatory response with a focus on pulmonary colibacillosis. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Prevalence of Antibodies to H9N2 Avian Influenza Virus in Backyard Chickens around Maharlou Lake in Iran

OpenAIRE

Mohammad Mehdi Hadipour*, Gholamhossein Habibi and Amir Vosoughi

2011-01-01

Backyard chickens play an important role in the epidemiology of H9N2 avian influenza virus infection. Close contact of backyard chickens with migratory birds, especially with aquatic birds, as well as neighboring poultry farms, may pose the risk of transmitting avian influenza virus, but little is known about the disease status of backyard poultry. A H9N2 avian influenza virus seroprevalence survey was carried out in 500 backyard chickens from villages around Maharlou lake in Iran, using the ...

Evaluation of Nobuto filter paper strips for the detection of avian influenza virus antibody in waterfowl

Science.gov (United States)

Dusek, Robert J.; Hall, Jeffrey S.; Nashold, Sean W.; Teslaa, Joshua L.; Ip, Hon S.

2011-01-01

The utility of using Nobuto paper strips for the detection of avian influenza antibodies was examined in mallards (Anas platyrhynchos) experimentally infected with low pathogenic avian influenza viruses. Blood was collected 2 wk after infection and was preserved either as serum or whole blood absorbed onto Nobuto strips. Analysis of samples using a commercially available blocking enzyme-linked immunosorbent assay revealed comparable results (???96% sensitivity for all methods) between sera stored at -30 C and the Nobuto strip preservation method even when the Nobuto strips were stored up to 3 mo at room temperature (RT). Significant differences were detected in the ratio of sample absorbance to negative control absorbance for Nobuto strips stored at RT compared with sera stored at -30 C, although these differences did not affect the ability of the test to reliably detect positive and negative samples. Nobuto strips are a convenient and sensitive alternative to the collection of serum samples when maintaining appropriate storage temperatures is difficult. ?? 2011 American Association of Avian Pathologists.

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

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Jeffrey S Hall

2009-10-01

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.

Contemporary avian influenza A virus subtype H1, H6, H7, H10, and H15 hemagglutinin genes encode a mammalian virulence factor similar to the 1918 pandemic virus H1 hemagglutinin.

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Qi, Li; Pujanauski, Lindsey M; Davis, A Sally; Schwartzman, Louis M; Chertow, Daniel S; Baxter, David; Scherler, Kelsey; Hartshorn, Kevan L; Slemons, Richard D; Walters, Kathie-Anne; Kash, John C; Taubenberger, Jeffery K

2014-11-18

Zoonotic avian influenza virus infections may lead to epidemics or pandemics. The 1918 pandemic influenza virus has an avian influenza virus-like genome, and its H1 hemagglutinin was identified as a key mammalian virulence factor. A chimeric 1918 virus expressing a contemporary avian H1 hemagglutinin, however, displayed murine pathogenicity indistinguishable from that of the 1918 virus. Here, isogenic chimeric avian influenza viruses were constructed on an avian influenza virus backbone, differing only by hemagglutinin subtype expressed. Viruses expressing the avian H1, H6, H7, H10, and H15 subtypes were pathogenic in mice and cytopathic in normal human bronchial epithelial cells, in contrast to H2-, H3-, H5-, H9-, H11-, H13-, H14-, and H16-expressing viruses. Mouse pathogenicity was associated with pulmonary macrophage and neutrophil recruitment. These data suggest that avian influenza virus hemagglutinins H1, H6, H7, H10, and H15 contain inherent mammalian virulence factors and likely share a key virulence property of the 1918 virus. Consequently, zoonotic infections with avian influenza viruses bearing one of these hemagglutinins may cause enhanced disease in mammals. Influenza viruses from birds can cause outbreaks in humans and may contribute to the development of pandemics. The 1918 pandemic influenza virus has an avian influenza virus-like genome, and its main surface protein, an H1 subtype hemagglutinin, was identified as a key mammalian virulence factor. In a previous study, a 1918 virus expressing an avian H1 gene was as virulent in mice as the reconstructed 1918 virus. Here, a set of avian influenza viruses was constructed, differing only by hemagglutinin subtype. Viruses with the avian H1, H6, H7, H10, and H15 subtypes caused severe disease in mice and damaged human lung cells. Consequently, infections with avian influenza viruses bearing one of these hemagglutinins may cause enhanced disease in mammals, and therefore surveillance for human infections

Production of monoclonal antibodies for Avian Metapneumovirus (SHS-BR-121 isolated in Brazil

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LT Coswig

2007-12-01

Full Text Available Avian Metapneumovirus (aMPV, also called Turkey Rhinotracheitis Virus (TRTV, is an upper respiratory tract infection of turkeys, chickens and other avian species. Five monoclonal antibodies (MAbs were created against the Brazilian isolate (SHS-BR-121 of aMPV, MAbs 1A5B8; 1C1C4; 2C2E9 and 2A4C3 of IgG1 and MAb 1C1F8 of IgG2a. Four Mabs (1A5B8; 1C1C4; 2C2E9 and 2A4C3 showed neutralizing activity and three (1A5B8; 1C1C4 and 2A4C3 inhibited cellular fusion in vitro. These MAbs were used to investigate antigenic relationship among three strains (SHS-BR-121, STG 854/88 and TRT 1439/91 of aMPV subtypes A and B using cross-neutralization test. The results confirm that the monoclonal antibodies described can be used as a valuable tool in the epizootiological and serological studies, and also for the specific diagnosis of the subtypes in the infection for Avian Metapneumovirus.

Persistence of highly pathogenic avian influenza virus (H7N1) in infected chickens: feather as a suitable sample for diagnosis.

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Busquets, Núria; Abad, F Xavier; Alba, Anna; Dolz, Roser; Allepuz, Alberto; Rivas, Raquel; Ramis, Antonio; Darji, Ayub; Majó, Natàlia

2010-09-01

Selection of an ideal sample is a vital element in early detection of influenza infection. Rapid identification of infectious individuals or animals is crucial not only for avian influenza virus (AIV) surveillance programmes, but also for treatment and containment strategies. This study used a combination of quantitative real-time RT-PCR with an internal positive control and a cell-titration system to examine the presence of virus in different samples during active experimental AIV infection and its persistence in the infected carcasses. Oropharyngeal/cloacal swabs as well as feather pulp and blood samples were collected from 15-day-old chicks infected with H7N1 highly pathogenic AIV (HPAIV) and the kinetics of virus shedding during active infection were evaluated. Additionally, several samples (muscle, skin, brain, feather pulp and oropharyngeal and cloacal swabs) were examined to assess the persistence of virus in the HPAIV-infected carcasses. Based on the results, feather pulp was found to be the best sample to detect and isolate HPAIV from infected chicks from 24 h after inoculation onwards. Kinetic studies on the persistence of virus in infected carcasses revealed that tissues such as muscle could potentially transmit infectious virus for 3 days post-mortem (p.m.), whilst other tissues such as skin, feather pulp and brain retained their infectivity for as long as 5-6 days p.m. at environmental temperature (22-23 degrees C). These results strongly favour feather as a useful sample for HPAIV diagnosis in infected chickens as well as in carcasses.

Contact variables for exposure to avian influenza H5N1 virus at the human-animal interface.

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Rabinowitz, P; Perdue, M; Mumford, E

2010-06-01

Although the highly pathogenic avian influenza H5N1 virus continues to cause infections in both avian and human populations, the specific zoonotic risk factors remain poorly understood. This review summarizes available evidence regarding types of contact associated with transmission of H5N1 virus at the human-animal interface. A systematic search of the published literature revealed five analytical studies and 15 case reports describing avian influenza transmission from animals to humans for further review. Risk factors identified in analytical studies were compared, and World Health Organization-confirmed cases, identified in case reports, were classified according to type of contact reported using a standardized algorithm. Although cases were primarily associated with direct contact with sick/unexpectedly dead birds, some cases reported only indirect contact with birds or contaminated environments or contact with apparently healthy birds. Specific types of contacts or activities leading to exposure could not be determined from data available in the publications reviewed. These results support previous reports that direct contact with sick birds is not the only means of human exposure to avian influenza H5N1 virus. To target public health measures and disease awareness messaging for reducing the risk of zoonotic infection with avian influenza H5N1 virus, the specific types of contacts and activities leading to transmission need to be further understood. The role of environmental virus persistence, shedding of virus by asymptomatic poultry and disease pathophysiology in different avian species relative to human zoonotic risk, as well as specific modes of zoonotic transmission, should be determined.

Genetic and biological characterisation of an avian-like H1N2 swine influenza virus generated by reassortment of circulating avian-like H1N1 and H3N2 subtypes in Denmark

DEFF Research Database (Denmark)

Trebbien, Ramona; Bragstad, Karoline; Larsen, Lars Erik

2013-01-01

BACKGROUND: The influenza A virus subtypes H1N1, H1N2 and H3N2 are the most prevalent subtypes in swine. In 2003, a reassorted H1N2 swine influenza virus (SIV) subtype appeared and became prevalent in Denmark. In the present study, the reassortant H1N2 subtype was characterised genetically...... and the infection dynamics compared to an “avian-like” H1N1 virus by an experimental infection study. METHODS: Sequence analyses were performed of the H1N2 virus. Two groups of pigs were inoculated with the reassortant H1N2 virus and an “avian-like” H1N1 virus, respectively, followed by inoculation...... with the opposite subtype four weeks later. Measurements of HI antibodies and acute phase proteins were performed. Nasal virus excretion and virus load in lungs were determined by real-time RT-PCR. RESULTS: The phylogenetic analysis revealed that the reassorted H1N2 virus contained a European “avian-like” H1-gene...

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

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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.

Avian mycoplasmosis update

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ER Nascimento

2005-03-01

Full Text Available Avian mycoplasmas occur in a variety of bird species. The most important mycoplasmas for chickens and turkeys are Mycoplasma gallisepticum (MG, M. synoviae (MS, and M. meleagridis. Besides, M. iowe (MI is an emerging pathogen in turkeys, but of little concern for chickens. Mycoplasmas are bacteria that lack cell wall and belong to the class Mollicutes. Although they have been considered extracellular agents, scientists admit nowadays that some of them are obligatory intracellular microorganisms, whereas all other mycoplasmas are considered facultative intracellular organisms. Their pathogenic mechanism for disease include adherence to host target cells, mediation of apoptosis, innocent bystander damage to host cell due to intimate membrane contact, molecular (antigen mimicry that may lead to tolerance, and mitotic effect for B and/or T lymphocytes, which could lead to suppressed T-cell function and/or production of cytotoxic T cell, besides mycoplasma by-products, such as hydrogen peroxide and superoxide radicals. Moreover, mycoplasma ability to stimulate macrophages, monocytes, T-helper cells and NK cells, results in the production of substances, such as tumor necrosing factor (TNF-alpha, interleukin (IL-1, 2, 6 and interferon (a, b, g. The major clinical signs seen in avian mycoplasmosis are coughing, sneezing, snicks, respiratory rales, ocular and nasal discharge, decreased feed intake and egg production, increased mortality, poor hatchability, and, primarily in turkeys, swelling of the infraorbital sinus(es. Nevertheless, chronic and unapparent infections are most common and more threatening. Mycoplasmas are transmitted horizontally, from bird to bird, and vertically, from dam to offspring through the eggs. Losses attributed to mycoplasmosis, mainly MG and MS infections, result from decreased egg production and egg quality, poor hatchability (high rate of embryonic mortality and culling of day-old birds, poor feed efficiency, increase in

Distinct Pathogenesis of Hong Kong-Origin H5N1 Viruses in Mice Compared to That of Other Highly Pathogenic H5 Avian Influenza Viruses

OpenAIRE

Dybing, Jody K.; Schultz-Cherry, Stacey; Swayne, David E.; Suarez, David L.; Perdue, Michael L.

2000-01-01

In 1997, an outbreak of virulent H5N1 avian influenza virus occurred in poultry in Hong Kong (HK) and was linked to a direct transmission to humans. The factors associated with transmission of avian influenza virus to mammals are not fully understood, and the potential risk of other highly virulent avian influenza A viruses infecting and causing disease in mammals is not known. In this study, two avian and one human HK-origin H5N1 virus along with four additional highly pathogenic H5 avian in...

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

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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.

Molecular Markers for Interspecies Transmission of Avian Influenza Viruses in Mammalian Hosts

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Lee, Taehyung

2017-01-01

In the last decade, a wide range of avian influenza viruses (AIVs) have infected various mammalian hosts and continuously threaten both human and animal health. It is a result of overcoming the inter-species barrier which is mostly associated with gene reassortment and accumulation of mutations in their gene segments. Several recent studies have shed insights into the phenotypic and genetic changes that are involved in the interspecies transmission of AIVs. These studies have a major focus on transmission from avian to mammalian species due to the high zoonotic potential of the viruses. As more mammalian species have been infected with these viruses, there is higher risk of genetic evolution of these viruses that may lead to the next human pandemic which represents and raises public health concern. Thus, understanding the mechanism of interspecies transmission and molecular determinants through which the emerging AIVs can acquire the ability to transmit to humans and other mammals is an important key in evaluating the potential risk caused by AIVs among humans. Here, we summarize previous and recent studies on molecular markers that are specifically involved in the transmission of avian-derived influenza viruses to various mammalian hosts including humans, pigs, horses, dogs, and marine mammals. PMID:29236050

Avian And Other Zoonotic Influenza

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... of Avian Influenza A(H5N1) Avian influenza: guidelines. recommendations, descriptions Global Influenza and Surveillance Response System (GISRS) Food safety authorities network OIE Avian Influenza ...

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

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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.

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.

Metapneumovirus aviar: diagnóstico y control (Avian Metapneumovirus: diagnosis and control)

OpenAIRE

Acevedo Beiras, Ana María.

2011-01-01

ResumenEl Metapneumovirus aviar (aMPV) causa una infección aguda, altamente contagiosa del tracto respiratorio superior principalmente en pavos y pollos.SummaryAvian metapneumovirus (aMPV) causes an acute highly contagious upper respiratory tract infection primarily of turkeys and chickens.

Live poultry market workers are susceptible to both avian and swine influenza viruses, Guangdong Province, China.

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Chen, Jidang; Ma, Jun; White, Sarah K; Cao, Zhenpeng; Zhen, Yun; He, Shuyi; Zhu, Wanjun; Ke, Changwen; Zhang, Yongbiao; Su, Shuo; Zhang, Guihong

2015-12-31

Guangdong Province is recognized for dense populations of humans, pigs, poultry and pets. In order to evaluate the threat of viral infection faced by those working with animals, a cross-sectional, sero-epidemiological study was conducted in Guangdong between December 2013 and January 2014. Individuals working with swine, at poultry farms, or live poultry markets (LPM), and veterinarians, and controls not exposed to animals were enrolled in this study and 11 (4 human, 3 swine, 3 avian, and 1 canine) influenza A viruses were used in hemagglutination inhibition (HI) assays (7 strains) and the cross-reactivity test (9 strains) in which 5 strains were used in both tests. Univariate analysis was performed to identify which variables were significantly associated with seropositivity. Odds ratios (OR) revealed that swine workers had a significantly higher risk of elevated antibodies against A/swine/Guangdong/L6/2009(H1N1), a classical swine virus, and A/swine/Guangdong/SS1/2012(H1N1), a Eurasian avian-like swine virus than non-exposed controls. Poultry farm workers were at a higher risk of infection with avian influenza H7N9 and H9N2. LPM workers were at a higher risk of infection with 3 subtypes of avian influenza, H5N1, H7N9, and H9N2. Interestingly, the OR also indicated that LPM workers were at risk of H1N1 swine influenza virus infection, perhaps due to the presence of pigs in the LPM. While partial confounding by cross-reactive antibodies against human viruses or vaccines cannot be ruled out, our data suggests that animal exposed people as are more likely to have antibodies against animal influenza viruses. Copyright © 2015 Elsevier B.V. All rights reserved.

The scientific rationale for the World Organisation for Animal Health standards and recommendations on avian influenza.

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Pasick, J; Kahn, S

2014-12-01

The World Organisation for Animal Health (OIE) prescribes standards for the diagnosis and control of avian influenza, as well as health measures for safe trade in birds and avian products, which are based on up-to-date scientific information and risk management principles, consistent with the role of the OIE as a reference standard-setting body for the World Trade Organization (WTO). These standards and recommendations continue to evolve, reflecting advances in technology and scientific understanding of this important zoonotic disease. The avian influenza viruses form part of the natural ecosystem by virtue of their ubiquitous presence in wild aquatic birds, a fact that human intervention cannot change. For the purposes of the Terrestrial Animal Health Code (Terrestrial Code), avian influenza is defined as an infection of poultry. However, the scope of the OIE standards and recommendations is not restricted to poultry, covering the diagnosis, early detection and management of avian influenza, including sanitary measures for trade in birds and avian products. The best way to manage avian influenza-associated risks to human and animal health is for countries to conduct surveillance using recommended methods, to report results in a consistent and transparent manner, and to applythe sanitary measures described in the Terrestrial Code. Surveillance for and timely reporting of avian influenza in accordance with OIE standards enable the distribution of relevant, up-to-date information to the global community.

Can lowland dry forests represent a refuge from avian malaria for native Hawaiian birds?

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Tucker-Mohl, Katherine; Hart, Patrick; Atkinson, Carter T.

2010-01-01

Hawaii's native birds have become increasingly threatened over the past century. Introduced mosquito borne diseases such as avian malaria may be responsible for the near absence of endemic Hawaiian forest birds in low-elevation habitats. The recent recognition that some native Hawaiian forest birds may be repopulating moist lowland habitats as a result of evolved resistance to this disease has increased the conservation value of these areas. Here, we investigate whether remnant low elevation dry forests on Hawaii Island provide natural 'refuges' from mosquito-transmitted malaria by nature of their low rainfall and absence of suitable natural sources of water for mosquito breeding. Unlike lowland wet forests where high rates of disease transmission may be selecting for disease resistance, lowland dry forests may provide some refuge for native forest birds without natural resistance to malaria. We mistnetted forest birds in two lowland dry forests and tested all native birds by microscopy and serology for avian malaria caused by the Plasmodium relictum parasite. We also conducted surveys for standing water and mosquito larvae. Overall prevalence of infections with Plasmodium relictum in the Hawaii Amakihi Hemignathus virens virens was 15%. Most infected birds had lowlevel parasitemias, suggesting chronic infections. Although avian malaria is present in these lowland dry forest Amakihi populations, infection rates are significantly lower than in wet forest populations at similar elevations. Sources of breeding mosquitoes in these forests appeared to be largely anthropogenic; thus, there is potential to manage dry forests as mosquito-free habitat for Hawaii Amakihi and other Hawaiian forest birds.

Update: Increase in Human Infections with Novel Asian Lineage Avian Influenza A(H7N9) Viruses During the Fifth Epidemic - China, October 1, 2016-August 7, 2017.

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Kile, James C; Ren, Ruiqi; Liu, Liqi; Greene, Carolyn M; Roguski, Katherine; Iuliano, A Danielle; Jang, Yunho; Jones, Joyce; Thor, Sharmi; Song, Ying; Zhou, Suizan; Trock, Susan C; Dugan, Vivien; Wentworth, David E; Levine, Min Z; Uyeki, Timothy M; Katz, Jacqueline M; Jernigan, Daniel B; Olsen, Sonja J; Fry, Alicia M; Azziz-Baumgartner, Eduardo; Davis, C Todd

2017-09-08

Among all influenza viruses assessed using CDC's Influenza Risk Assessment Tool (IRAT), the Asian lineage avian influenza A(H7N9) virus (Asian H7N9), first reported in China in March 2013,* is ranked as the influenza virus with the highest potential pandemic risk (1). During October 1, 2016-August 7, 2017, the National Health and Family Planning Commission of China; CDC, Taiwan; the Hong Kong Centre for Health Protection; and the Macao CDC reported 759 human infections with Asian H7N9 viruses, including 281 deaths, to the World Health Organization (WHO), making this the largest of the five epidemics of Asian H7N9 infections that have occurred since 2013 (Figure 1). This report summarizes new viral and epidemiologic features identified during the fifth epidemic of Asian H7N9 in China and summarizes ongoing measures to enhance pandemic preparedness. Infections in humans and poultry were reported from most areas of China, including provinces bordering other countries, indicating extensive, ongoing geographic spread. The risk to the general public is very low and most human infections were, and continue to be, associated with poultry exposure, especially at live bird markets in mainland China. Throughout the first four epidemics of Asian H7N9 infections, only low pathogenic avian influenza (LPAI) viruses were detected among human, poultry, and environmental specimens and samples. During the fifth epidemic, mutations were detected among some Asian H7N9 viruses, identifying the emergence of high pathogenic avian influenza (HPAI) viruses as well as viruses with reduced susceptibility to influenza antiviral medications recommended for treatment. Furthermore, the fifth-epidemic viruses diverged genetically into two separate lineages (Pearl River Delta lineage and Yangtze River Delta lineage), with Yangtze River Delta lineage viruses emerging as antigenically different compared with those from earlier epidemics. Because of its pandemic potential, candidate vaccine viruses

No evidence of transmission of H5N1 highly pathogenic avian influenza to humans after unprotected contact with infected wild swans.

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Wallensten, A; Salter, M; Bennett, S; Brown, I; Hoschler, K; Oliver, I

2010-02-01

Highly pathogenic avian influenza (HPAI) subtype H5N1 remains a public health threat as long as it circulates in wild and domestic birds. Information on the transmissibility of H5N1 HPAI from wild birds is needed for evidence-based public health advice. We investigated if transmission of H5N1 HPAI had taken place in people that had unprotected contact with infected wild mute swans during an incident at the Abbotsbury Swannery in Dorset, England. Thirteen people who had been exposed to infected swans were contacted and actively followed up for symptoms. Serology was taken after 30 days. We did not find evidence of transmission of H5N1 HPAI to humans during the incident. The incident provided a rare opportunity to study the transmissibility of the virus from wild birds to humans.

Published sequences do not support transfer of oseltamivir resistance mutations from avian to human influenza A virus strains.

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Norberg, Peter; Lindh, Magnus; Olofsson, Sigvard

2015-03-28

Tamiflu (oseltamivir phosphate ester, OE) is a widely used antiviral active against influenza A virus. Its active metabolite, oseltamivir carboxylate (OC), is chemically stable and secreted into wastewater treatment plants. OC contamination of natural habitats of waterfowl might induce OC resistance in influenza viruses persistently infecting waterfowl, and lead to transfer of OC-resistance from avian to human influenza. The aim of this study was to evaluate whether such has occurred. A genomics approach including phylogenetic analysis and probability calculations for homologous recombination was applied on altogether 19,755 neuraminidase (N1 and N2) genes from virus sampled in humans and birds, with and without resistance mutations. No evidence for transfer of OE resistance mutations from avian to human N genes was obtained, and events suggesting recombination between human and avian influenza virus variants could not be traced in the sequence material studied. The results indicate that resistance in influenza viruses infecting humans is due to the selection pressure posed by the global OE administration in humans rather than transfer from avian influenza A virus strains carrying mutations induced by environmental exposure to OC.

Description of the first cryptic avian malaria parasite, Plasmodium homocircumflexum n. sp., with experimental data on its virulence and development in avian hosts and mosquitoes.

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Palinauskas, Vaidas; Žiegytė, Rita; Ilgūnas, Mikas; Iezhova, Tatjana A; Bernotienė, Rasa; Bolshakov, Casimir; Valkiūnas, Gediminas

2015-01-01

For over 100 years studies on avian haemosporidian parasite species have relied on similarities in their morphology to establish a species concept. Some exceptional cases have also included information about the life cycle and sporogonic development. More than 50 avian Plasmodium spp. have now been described. However, PCR-based studies show a much broader diversity of haemosporidian parasites, indicating the possible existence of a diverse group of cryptic species. In the present study, using both similarity and phylogenetic species definition concepts, we believe that we report the first characterised cryptic speciation case of an avian Plasmodium parasite. We used sequence information on the mitochondrial cytochrome b gene and constructed phylogenies of identified Plasmodium spp. to define their position in the phylogenetic tree. After analysis of blood stages, the morphology of the parasite was shown to be identical to Plasmodium circumflexum. However, the geographic distribution of the new parasite, the phylogenetic information, as well as patterns of development of infection, indicate that this parasite differs from P. circumflexum. Plasmodium homocircumflexum n. sp. was described based on information about genetic differences from described lineages, phylogenetic position and biological characters. This parasite develops parasitemia in experimentally infected birds - the domestic canary Serinus canaria domestica, siskin Carduelis spinus and crossbill Loxia curvirostra. Anaemia caused by high parasitemia, as well as cerebral paralysis caused by exoerythrocytic stages in the brain, are the main reasons for mortality. Exoerythrocytic stages also form in other organs (heart, kidneys, liver, lungs, spleen, intestines and pectoral muscles). DNA amplification was unsuccessful from faecal samples of heavily infected birds. The sporogonic development initiates, but is abortive, at the oocyst stage in two common European mosquito species, Culex pipiens pipiens (forms

Discordant detection of avian influenza virus subtypes in time and space between poultry and wild birds; Towards improvement of surveillance programs

NARCIS (Netherlands)

Verhagen, Josanne H.; Lexmond, Pascal; Vuong, Oanh; Schutten, Martin; Guldemeester, Judith; Osterhaus, Albert D.M.E.; Elbers, Armin R.W.; Slaterus, Roy; Hornman, Menno; Koch, Guus; Fouchier, Ron A.M.; Lierz, Michael

2017-01-01

Avian influenza viruses from wild birds can cause outbreaks in poultry, and occasionally infect humans upon exposure to infected poultry. Identification and characterization of viral reservoirs and transmission routes is important to develop strategies that prevent infection of poultry, and

Experimental infection of highly pathogenic avian influenza virus H5N1 in black-headed gulls (Chroicocephalus ridibundus).

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Ramis, Antonio; van Amerongen, Geert; van de Bildt, Marco; Leijten, Loneke; Vanderstichel, Raphael; Osterhaus, Albert; Kuiken, Thijs

2014-08-19

Historically, highly pathogenic avian influenza viruses (HPAIV) rarely resulted in infection or clinical disease in wild birds. However, since 2002, disease and mortality from natural HPAIV H5N1 infection have been observed in wild birds including gulls. We performed an experimental HPAIV H5N1 infection of black-headed gulls (Chroicocephalus ridibundus) to determine their susceptibility to infection and disease from this virus, pattern of viral shedding, clinical signs, pathological changes and viral tissue distribution. We inoculated sixteen black-headed gulls with 1 × 10(4) median tissue culture infectious dose HPAIV H5N1 (A/turkey/Turkey/1/2005) intratracheally and intraesophageally. Birds were monitored daily until 12 days post inoculation (dpi). Oropharyngeal and cloacal swabs were collected daily to detect viral shedding. Necropsies from birds were performed at 2, 4, 5, 6, 7, and 12 dpi. Sampling from selected tissues was done for histopathology, immunohistochemical detection of viral antigen, PCR, and viral isolation. Our study shows that all inoculated birds were productively infected, developed systemic disease, and had a high morbidity and mortality rate. Virus was detected mainly in the respiratory tract on the first days after inoculation, and then concentrated more in pancreas and central nervous system from 4 dpi onwards. Birds shed infectious virus until 7 dpi from the pharynx and 6 dpi from the cloaca. We conclude that black-headed gulls are highly susceptible to disease with a high mortality rate and are thus more likely to act as sentinel species for the presence of the virus than as long-distance carriers of the virus to new geographical areas.

Avian influenza virus transmission to mammals.

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Herfst, S; Imai, M; Kawaoka, Y; Fouchier, R A M

2014-01-01

Influenza A viruses cause yearly epidemics and occasional pandemics. In addition, zoonotic influenza A viruses sporadically infect humans and may cause severe respiratory disease and fatalities. Fortunately, most of these viruses do not have the ability to be efficiently spread among humans via aerosols or respiratory droplets (airborne transmission) and to subsequently cause a pandemic. However, adaptation of these zoonotic viruses to humans by mutation or reassortment with human influenza A viruses may result in airborne transmissible viruses with pandemic potential. Although our knowledge of factors that affect mammalian adaptation and transmissibility of influenza viruses is still limited, we are beginning to understand some of the biological traits that drive airborne transmission of influenza viruses among mammals. Increased understanding of the determinants and mechanisms of airborne transmission may aid in assessing the risks posed by avian influenza viruses to human health, and preparedness for such risks. This chapter summarizes recent discoveries on the genetic and phenotypic traits required for avian influenza viruses to become airborne transmissible between mammals.

Risk maps for the spread of highly pathogenic avian influenza in poultry.

Directory of Open Access Journals (Sweden)

Gert Jan Boender

2007-04-01

Full Text Available Devastating epidemics of highly contagious animal diseases such as avian influenza, classical swine fever, and foot-and-mouth disease underline the need for improved understanding of the factors promoting the spread of these pathogens. Here the authors present a spatial analysis of the between-farm transmission of a highly pathogenic H7N7 avian influenza virus that caused a large epidemic in The Netherlands in 2003. The authors developed a method to estimate key parameters determining the spread of highly transmissible animal diseases between farms based on outbreak data. The method allows for the identification of high-risk areas for propagating spread in an epidemiologically underpinned manner. A central concept is the transmission kernel, which determines the probability of pathogen transmission from infected to uninfected farms as a function of interfarm distance. The authors show how an estimate of the transmission kernel naturally provides estimates of the critical farm density and local reproduction numbers, which allows one to evaluate the effectiveness of control strategies. For avian influenza, the analyses show that there are two poultry-dense areas in The Netherlands where epidemic spread is possible, and in which local control measures are unlikely to be able to halt an unfolding epidemic. In these regions an epidemic can only be brought to an end by the depletion of susceptible farms by infection or massive culling. The analyses provide an estimate of the spatial range over which highly pathogenic avian influenza viruses spread between farms, and emphasize that control measures aimed at controlling such outbreaks need to take into account the local density of farms.

Antigenic Characterization of H3 Subtypes of Avian Influenza A Viruses from North America.

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Bailey, Elizabeth; Long, Li-Ping; Zhao, Nan; Hall, Jeffrey S; Baroch, John A; Nolting, Jacqueline; Senter, Lucy; Cunningham, Frederick L; Pharr, G Todd; Hanson, Larry; Slemons, Richard; DeLiberto, Thomas J; Wan, Xiu-Feng

2016-05-01

Besides humans, H3 subtypes of influenza A viruses (IAVs) can infect various animal hosts, including avian, swine, equine, canine, and sea mammal species. These H3 viruses are both antigenically and genetically diverse. Here, we characterized the antigenic diversity of contemporary H3 avian IAVs recovered from migratory birds in North America. Hemagglutination inhibition (HI) assays were performed on 37 H3 isolates of avian IAVs recovered from 2007 to 2011 using generated reference chicken sera. These isolates were recovered from samples taken in the Atlantic, Mississippi, Central, and Pacific waterfowl migration flyways. Antisera to all the tested H3 isolates cross-reacted with each other and, to a lesser extent, with those to H3 canine and H3 equine IAVs. Antigenic cartography showed that the largest antigenic distance among the 37 avian IAVs is about four units, and each unit corresponds to a 2 log 2 difference in the HI titer. However, none of the tested H3 IAVs cross-reacted with ferret sera derived from contemporary swine and human IAVs. Our results showed that the H3 avian IAVs we tested lacked significant antigenic diversity, and these viruses were antigenically different from those circulating in swine and human populations. This suggests that H3 avian IAVs in North American waterfowl are antigenically relatively stable.

Vaccinating chickens against avian influenza with fowlpox recombinants expressing the H7 haemagglutinin.

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Boyle, D B; Selleck, P; Heine, H G

2000-01-01

To evaluate the vaccine efficacy of a fowlpox virus recombinant expressing the H7 haemagglutinin of avian influenza virus in poultry. Specific-pathogen-free poultry were vaccinated with fowlpox recombinants expressing H7 or H1 haemagglutinins of influenza virus. Chickens were vaccinated at 2 or 7 days of age and challenged with virulent Australian avian influenza virus at 10 and 21 days later, respectively. Morbidity and mortality, body weight change and the development of immune responses to influenza haemagglutinin and nucleoprotein were recorded. Vaccination of poultry with fowlpox H7 avian influenza virus recombinants induced protective immune responses. All chickens vaccinated at 7 days of age and challenged 21 days later were protected from death. Few clinical signs of infection developed. In contrast, unvaccinated or chickens vaccinated with a non-recombinant fowlpox or a fowlpox expressing the H1 haemagglutinin of human influenza were highly susceptible to avian influenza. All those chickens died within 72 h of challenge. In younger chickens, vaccinated at 2 days of age and challenged 10 days later the protection was lower with 80% of chickens protected from death. Chickens surviving vaccination and challenge had high antibody responses to haemagglutinin and primary antibody responses to nucleoprotein suggesting that although vaccination protected substantially against disease it failed to completely prevent replication of the challenge avian influenza virus. Vaccination of chickens with fowlpox virus expressing the avian influenza H7 haemagglutinin provided good protection against experimental challenge with virulent avian influenza of H7 type. Although eradication will remain the method of first choice for control of avian influenza, in the circumstances of a continuing and widespread outbreak the availability of vaccines based upon fowlpox recombinants provides an additional method for disease control.

Physician's knowledge, attitudes, and practices regarding seasonal influenza, pandemic influenza, and highly pathogenic avian influenza A (H5N1) virus infections of humans in Indonesia

OpenAIRE

Mangiri, Amalya; Iuliano, A. Danielle; Wahyuningrum, Yunita; Praptiningsih, Catharina Y.; Lafond, Kathryn E.; Storms, Aaron D.; Samaan, Gina; Ariawan, Iwan; Soeharno, Nugroho; Kreslake, Jennifer M.; Storey, J. Douglas; Uyeki, Timothy M.

2016-01-01

Indonesia has reported highest number of fatal human cases of highly pathogenic avian influenza (HPAI) A (H5N1) virus infection worldwide since 2005. There are limited data available on seasonal and pandemic influenza in Indonesia. During 2012, we conducted a survey of clinicians in two districts in western Java, Indonesia, to assess knowledge, attitudes, and practices (KAP) of clinical diagnosis, testing, and treatment of patients with seasonal influenza, pandemic influenza, or HPAI H5N1 vir...

Low pathogenic avian influenza isolates from wild birds replicate and transmit via contact in ferrets without prior adaptation.

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Driskell, Elizabeth A; Pickens, Jennifer A; Humberd-Smith, Jennifer; Gordy, James T; Bradley, Konrad C; Steinhauer, David A; Berghaus, Roy D; Stallknecht, David E; Howerth, Elizabeth W; Tompkins, Stephen Mark

2012-01-01

Direct transmission of avian influenza viruses to mammals has become an increasingly investigated topic during the past decade; however, isolates that have been primarily investigated are typically ones originating from human or poultry outbreaks. Currently there is minimal comparative information on the behavior of the innumerable viruses that exist in the natural wild bird host. We have previously demonstrated the capacity of numerous North American avian influenza viruses isolated from wild birds to infect and induce lesions in the respiratory tract of mice. In this study, two isolates from shorebirds that were previously examined in mice (H1N9 and H6N1 subtypes) are further examined through experimental inoculations in the ferret with analysis of viral shedding, histopathology, and antigen localization via immunohistochemistry to elucidate pathogenicity and transmission of these viruses. Using sequence analysis and glycan binding analysis, we show that these avian viruses have the typical avian influenza binding pattern, with affinity for cell glycoproteins/glycolipids having terminal sialic acid (SA) residues with α 2,3 linkage [Neu5Ac(α2,3)Gal]. Despite the lack of α2,6 linked SA binding, these AIVs productively infected both the upper and lower respiratory tract of ferrets, resulting in nasal viral shedding and pulmonary lesions with minimal morbidity. Moreover, we show that one of the viruses is able to transmit to ferrets via direct contact, despite its binding affinity for α 2,3 linked SA residues. These results demonstrate that avian influenza viruses, which are endemic in aquatic birds, can potentially infect humans and other mammals without adaptation. Finally this work highlights the need for additional study of the wild bird subset of influenza viruses in regard to surveillance, transmission, and potential for reassortment, as they have zoonotic potential.

Characterizing wild bird contact and seropositivity to highly pathogenic avian influenza A (H5N1) virus in Alaskan residents.

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Reed, Carrie; Bruden, Dana; Byrd, Kathy K; Veguilla, Vic; Bruce, Michael; Hurlburt, Debby; Wang, David; Holiday, Crystal; Hancock, Kathy; Ortiz, Justin R; Klejka, Joe; Katz, Jacqueline M; Uyeki, Timothy M

2014-09-01

Highly pathogenic avian influenza A (HPAI) H5N1 viruses have infected poultry and wild birds on three continents with more than 600 reported human cases (59% mortality) since 2003. Wild aquatic birds are the natural reservoir for avian influenza A viruses, and migratory birds have been documented with HPAI H5N1 virus infection. Since 2005, clade 2.2 HPAI H5N1 viruses have spread from Asia to many countries. We conducted a cross-sectional seroepidemiological survey in Anchorage and western Alaska to identify possible behaviors associated with migratory bird exposure and measure seropositivity to HPAI H5N1. We enrolled rural subsistence bird hunters and their families, urban sport hunters, wildlife biologists, and a comparison group without bird contact. We interviewed participants regarding their exposures to wild birds and collected blood to perform serologic testing for antibodies against a clade 2.2 HPAI H5N1 virus strain. Hunters and wildlife biologists reported exposures to wild migratory birds that may confer risk of infection with avian influenza A viruses, although none of the 916 participants had evidence of seropositivity to HPAI H5N1. We characterized wild bird contact among Alaskans and behaviors that may influence risk of infection with avian influenza A viruses. Such knowledge can inform surveillance and risk communication surrounding HPAI H5N1 and other influenza viruses in a population with exposure to wild birds at a crossroads of intercontinental migratory flyways. © 2014 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

Naturally Occurring Frameshift Mutations in the tvb Receptor Gene Are Responsible for Decreased Susceptibility of Chicken to Infection with Avian Leukosis Virus Subgroups B, D, and E.

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Li, Xinjian; Chen, Weiguo; Zhang, Huanmin; Li, Aijun; Shu, Dingming; Li, Hongxing; Dai, Zhenkai; Yan, Yiming; Zhang, Xinheng; Lin, Wencheng; Ma, Jingyun; Xie, Qingmei

2018-04-15

The group of highly related avian leukosis viruses (ALVs) in chickens are thought to have evolved from a common retroviral ancestor into six subgroups, A to E and J. These ALV subgroups use diverse cellular proteins encoded by four genetic loci in chickens as receptors to gain entry into host cells. Hosts exposed to ALVs might be under selective pressure to develop resistance to ALV infection. Indeed, resistance alleles have previously been identified in all four receptor loci in chickens. The tvb gene encodes a receptor, which determines the susceptibility of host cells to ALV subgroup B (ALV-B), ALV-D, and ALV-E. Here we describe the identification of two novel alleles of the tvb receptor gene, which possess independent insertions each within exon 4. The insertions resulted in frameshift mutations that reveal a premature stop codon that causes nonsense-mediated decay of the mutant mRNA and the production of truncated Tvb protein. As a result, we observed that the frameshift mutations in the tvb gene significantly lower the binding affinity of the truncated Tvb receptors for the ALV-B, ALV-D, and ALV-E envelope glycoproteins and significantly reduce susceptibility to infection by ALV-B, ALV-D and ALV-E in vitro and in vivo Taken together, these findings suggest that frameshift mutation can be a molecular mechanism of reducing susceptibility to ALV and enhance our understanding of virus-host coevolution. IMPORTANCE Avian leukosis virus (ALV) once caused devastating economic loss to the U.S. poultry industry prior the current eradication schemes in place, and it continues to cause severe calamity to the poultry industry in China and Southeast Asia, where deployment of a complete eradication scheme remains a challenge. The tvb gene encodes the cellular receptor necessary for subgroup B, D, and E ALV infection. Two tvb allelic variants that resulted from frameshift mutations have been identified in this study, which have been shown to have significantly reduced

Investigations on the protective role of passively transferred antibodies against avian metapneumovirus infection in turkeys.

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Rubbenstroth, Dennis; Rautenschlein, Silke

2009-12-01

The avian metapneumovirus (aMPV) is the causative agent of an acute respiratory disease in turkeys, which causes considerable economic losses to the poultry industry. Currently attenuated live and inactivated vaccines are widely used to control the disease, but vaccine breaks are frequently observed. For improvement of current vaccination strategies it is necessary to gain enhanced knowledge of the immune mechanisms against aMPV infection. Field observations suggest that vaccine-induced aMPV-specific antibodies are not indicative for protection. In the present study we investigated the role of antibodies in protection of turkeys against aMPV. In two experiments, commercial turkey poults received aMPV-specific antibodies by intravenous injection. The antibody transfer resulted in increased antibody levels in the sera. Virus-specific antibodies were also detected on mucosal surfaces such as the trachea, conjunctivae and gall bladder. Turkeys were subsequently challenged with a virulent aMPV subtype A strain. Development of clinical signs, virus detection by polymerase chain reaction and histopathological changes of tracheal mucosa in challenged turkeys with and without passively transferred antibodies were comparable with each other. Our results suggest that humoral immunity does not provide sufficient protection against aMPV infection. Thus, the measurement of vaccine-induced aMPV antibody response may not be considered as an adequate indicator of vaccine efficacy. Further research on the protective role of cell-mediated immune mechanisms is necessary to improve current vaccine strategies.

Mannose-binding lectin contributes to deleterious inflammatory response in pandemic H1N1 and avian H9N2 infection.

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Ling, Man To; Tu, Wenwei; Han, Yan; Mao, Huawei; Chong, Wai Po; Guan, Jing; Liu, Ming; Lam, Kwok Tai; Law, Helen K W; Peiris, J S Malik; Takahashi, K; Lau, Yu Lung

2012-01-01

Mannose-binding lectin (MBL) is a pattern-recognition molecule, which functions as a first line of host defense. Pandemic H1N1 (pdmH1N1) influenza A virus caused massive infection in 2009 and currently circulates worldwide. Avian influenza A H9N2 (H9N2/G1) virus has infected humans and has the potential to be the next pandemic virus. Antiviral function and immunomodulatory role of MBL in pdmH1N1 and H9N2/G1 virus infection have not been investigated. In this study, MBL wild-type (WT) and MBL knockout (KO) murine models were used to examine the role of MBL in pdmH1N1 and H9N2/G1 virus infection. Our study demonstrated that in vitro, MBL binds to pdmH1N1 and H9N2/G1 viruses, likely via the carbohydrate recognition domain of MBL. Wild-type mice developed more severe disease, as evidenced by a greater weight loss than MBL KO mice during influenza virus infection. Furthermore, MBL WT mice had enhanced production of proinflammatory cytokines and chemokines compared with MBL KO mice, suggesting that MBL could upregulate inflammatory responses that may potentially worsen pdmH1N1 and H9N2/G1 virus infections. Our study provided the first in vivo evidence that MBL may be a risk factor during pdmH1N1 and H9N2/G1 infection by upregulating proinflammatory response.

Thromboelastography in Selected Avian Species

DEFF Research Database (Denmark)

Andersen, Sophie Susanna Strindberg; Nielsen, Tenna W; Ribeiro, Ângela M

2015-01-01

Currently available assay methods and reagents are not optimized for evaluating avian hemostasis; therefore, assessing avian coagulopathies is challenging. Recently, thromboelastography (TEG), which measures the viscoelastic properties of blood, has been used clinically in mammalian species...... to diagnose and characterize hemostatic disorders. To evaluate TEG in healthy individuals of 6 avian species, we modified existing mammalian TEG protocols to allow analysis of citrated, avian whole-blood samples collected from scarlet ibis (Eudocimus ruber) (n = 13), American flamingos ( Phoenicopterus ruber...

Vaccination against H9N2 avian influenza virus reduces bronchus-associated lymphoid tissue formation in cynomolgus macaques after intranasal virus challenge infection.

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Nakayama, Misako; Ozaki, Hiroichi; Itoh, Yasushi; Soda, Kosuke; Ishigaki, Hirohito; Okamatsu, Masatoshi; Sakoda, Yoshihiro; Park, Chun-Ho; Tsuchiya, Hideaki; Kida, Hiroshi; Ogasawara, Kazumasa

2016-12-01

H9N2 avian influenza virus causes sporadic human infection. Since humans do not possess acquired immunity specific to this virus, we examined the pathogenicity of an H9N2 virus isolated from a human and then analyzed protective effects of a vaccine in cynomolgus macaques. After intranasal challenge with A/Hong Kong/1073/1999 (H9N2) (HK1073) isolated from a human patient, viruses were isolated from nasal and tracheal swabs in unvaccinated macaques with mild fever and body weight loss. A formalin-inactivated H9N2 whole particle vaccine derived from our virus library was subcutaneously inoculated to macaques. Vaccination induced viral antigen-specific IgG and neutralization activity in sera. After intranasal challenge with H9N2, the virus was detected only the day after inoculation in the vaccinated macaques. Without vaccination, many bronchus-associated lymphoid tissues (BALTs) were formed in the lungs after infection, whereas the numbers of BALTs were smaller and the cytokine responses were weaker in the vaccinated macaques than those in the unvaccinated macaques. These findings indicate that the H9N2 avian influenza virus HK1073 is pathogenic in primates but seems to cause milder symptoms than does H7N9 influenza virus as found in our previous studies and that a formalin-inactivated H9N2 whole particle vaccine induces protective immunity against H9N2 virus. © 2016 Japanese Society of Pathology and John Wiley & Sons Australia, Ltd.

Investigation of avian influenza virus in poultry and wild birds due to novel avian-origin influenza A(H10N8) in Nanchang City, China.

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Ni, Xiansheng; He, Fenglan; Hu, Maohong; Zhou, Xianfeng; Wang, Bin; Feng, Changhua; Wu, Yumei; Li, Youxing; Tu, Junling; Li, Hui; Liu, Mingbin; Chen, Haiying; Chen, Shengen

2015-01-01

Multiple reassortment events within poultry and wild birds had resulted in the establishment of another novel avian influenza A(H10N8) virus, and finally resulted in human death in Nanchang, China. However, there was a paucity of information on the prevalence of avian influenza virus in poultry and wild birds in Nanchang area. We investigated avian influenza virus in poultry and wild birds from live poultry markets, poultry countyards, delivery vehicles, and wild-bird habitats in Nanchang. We analyzed 1036 samples from wild birds and domestic poultry collected from December 2013 to February 2014. Original biological samples were tested for the presence of avian influenza virus using specific primer and probe sets of H5, H7, H9, H10 and N8 subtypes by real-time RT-PCR. In our analysis, the majority (97.98%) of positive samples were from live poultry markets. Among the poultry samples from chickens and ducks, AIV prevalence was 26.05 and 30.81%, respectively. Mixed infection of different HA subtypes was very common. Additionally, H10 subtypes coexistence with N8 was the most prevalent agent during the emergence of H10N8. This event illustrated a long-term surveillance was so helpful for pandemic preparedness and response. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Seroprevalence of avian influenza A (H5N1 virus among poultry workers in Jiangsu Province, China: an observational study

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Huo Xiang

2012-04-01

Full Text Available Abstract Background Since 2003 to 06 Jan 2012, the number of laboratory confirmed human cases of infection with avian influenza in China was 41 and 27 were fatal. However, the official estimate of the H5N1 case-fatality rate has been described by some as an over estimation since there may be numerous undetected asymptomatic/mild cases of H5N1 infection. This study was conducted to better understand the real infection rate and evaluate the potential risk factors for the zoonotic spread of H5N1 viruses to humans. Methods A seroepidemiological survey was conducted in poultry workers, a group expected to have the highest level of exposure to H5N1-infected birds, from 3 counties with habitat lakes of wildfowl in Jiangsu province, China. Serum specimens were collected from 306 participants for H5N1 serological test. All participants were interviewed to collect information about poultry exposures. Results The overall seropositive rate was 2.61% for H5N1 antibodies. The poultry number was found associated with a 2.39-fold significantly increased subclinical infection risk after adjusted with age and gender. Conclusions Avian-to -human transmission of avian H5N1 virus remained low. Workers associated with raising larger poultry flocks have a higher risk on seroconversion.

Pathological alterations in respiratory system during co-infection with low pathogenic avian influenza virus (H9N2 and Escherichia coli in broiler chickens

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Jaleel Shahid

2017-09-01

Full Text Available Introduction: Despite the advancements in the field, there is a lack of data when it comes to co-infections in poultry. Therefore, this study was designed to address this issue. Material and Methods: Broiler birds were experimentally infected with E. coli (O78 and low pathogenic avian influenza (LPAI strain, alone or in combination. The experimental groups were negative control. Results: The infected birds showed most severe clinical signs in E. coli+LPAI group along with a significant decrease in weight and enhanced macroscopic and microscopic pathological lesions. The survival rate was 60%, 84%, and 100% in birds inoculated with E. coli+LPAI, E. coli, and LPAI virus alone, respectively. The results showed that experimental co-infection with E. coli and H9N2 strain of LPAI virus increased the severity of clinical signs, mortality rate, and gross lesions. The HI titre against LPAI virus infection in the co-infected group was significantly higher than the HI titre of LPAI group, which may indicate that E. coli may promote propagation of H9N2 LPAI virus by alteration of immune response. Conclusion: The present study revealed that co-infection with E. coli and H9N2 LPAI virus caused more serious synergistic pathogenic effects and indicates the role of both pathogens as complicating factors in poultry infections.

Serological evidence of avian encephalomyelitis virus and Pasteurella multocida infections in free-range indigenous chickens in Southern Mozambique.

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Taunde, Paula; Timbe, Palmira; Lucas, Ana Felicidade; Tchamo, Cesaltina; Chilundo, Abel; Dos Anjos, Filomena; Costa, Rosa; Bila, Custodio Gabriel

2017-06-01

A total of 398 serum samples from free-range indigenous chickens originating from four villages in Southern Mozambique were tested for the presence of avian encephalomyelitis virus (AEV) and Pasteurella multocida (PM) antibodies through commercial enzyme-linked immunosorbent assay (ELISA) kits. AEV and PM antibodies were detected in all villages surveyed. The proportion of positive samples was very high: 59.5% (95% confidence interval (CI) 51.7-67.7%) for AEV and 71.5% (95% CI 67.7-77.3%) for PM. Our findings revealed that these pathogens are widespread among free-range indigenous chickens in the studied villages and may represent a threat in the transmission of AEV and PM to wild, broiler or layer chickens in the region. Further research is warranted on epidemiology of circulating strains and impact of infection on the poultry industry.

RT-PCR-ELISA as a tool for diagnosis of low-pathogenicity avian influenza

DEFF Research Database (Denmark)

Dybkaer, Karen; Munch, Mette; Handberg, Kurt Jensen

2003-01-01

A one-tube reverse transcriptase/polymerase chain reaction coupled with an enzyme-linked immunosorbent assay (RT-PCR-ELISA) was developed for the rapid detection of avian influenza virus (AIV) in clinical specimens. A total of 419 swab pools were analyzed from chickens experimentally infected...

Wind-mediated spread of low-pathogenic avian influenza virus into the environment during outabreaks at commercial poultry farms

NARCIS (Netherlands)

Jonges, Marcel; Leuken, Van Jeroen; Wouters, Inge; Koch, Guus; Meijer, Adam; Koopmans, Marion

2015-01-01

Avian influenza virus-infected poultry can release a large amount of virus-contaminated droppings that serve as sources of infection for susceptible birds. Much research so far has focused on virus spread within flocks. However, as fecal material or manure is a major constituent of airborne

Contemporary Avian Influenza A Virus Subtype H1, H6, H7, H10, and H15 Hemagglutinin Genes Encode a Mammalian Virulence Factor Similar to the 1918 Pandemic Virus H1 Hemagglutinin

OpenAIRE

Qi, Li; Pujanauski, Lindsey M.; Davis, A. Sally; Schwartzman, Louis M.; Chertow, Daniel S.; Baxter, David; Scherler, Kelsey; Hartshorn, Kevan L.; Slemons, Richard D.; Walters, Kathie-Anne; Kash, John C.; Taubenberger, Jeffery K.

2014-01-01

ABSTRACT Zoonotic avian influenza virus infections may lead to epidemics or pandemics. The 1918 pandemic influenza virus has an avian influenza virus-like genome, and its H1 hemagglutinin was identified as a key mammalian virulence factor. A chimeric 1918 virus expressing a contemporary avian H1 hemagglutinin, however, displayed murine pathogenicity indistinguishable from that of the 1918 virus. Here, isogenic chimeric avian influenza viruses were constructed on an avian influenza virus backb...

Chromosomal features of Escherichia coli serotype O2:K2, an avian pathogenic E. coli.

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Jørgensen, Steffen L; Kudirkiene, Egle; Li, Lili; Christensen, Jens P; Olsen, John E; Nolan, Lisa; Olsen, Rikke H

2017-01-01

Escherichia coli causing infection outside the gastrointestinal system are referred to as extra-intestinal pathogenic E. coli. Avian pathogenic E. coli is a subgroup of extra-intestinal pathogenic E. coli and infections due to avian pathogenic E. coli have major impact on poultry production economy and welfare worldwide. An almost defining characteristic of avian pathogenic E. coli is the carriage of plasmids, which may encode virulence factors and antibiotic resistance determinates. For the same reason, plasmids of avian pathogenic E. coli have been intensively studied. However, genes encoded by the chromosome may also be important for disease manifestation and antimicrobial resistance. For the E. coli strain APEC_O2 the plasmids have been sequenced and analyzed in several studies, and E. coli APEC_O2 may therefore serve as a reference strain in future studies. Here we describe the chromosomal features of E. coli APEC_O2. E. coli APEC_O2 is a sequence type ST135, has a chromosome of 4,908,820 bp (plasmid removed), comprising 4672 protein-coding genes, 110 RNA genes, and 156 pseudogenes, with an average G + C content of 50.69%. We identified 82 insertion sequences as well as 4672 protein coding sequences, 12 predicated genomic islands, three prophage-related sequences, and two clustered regularly interspaced short palindromic repeats regions on the chromosome, suggesting the possible occurrence of horizontal gene transfer in this strain. The wildtype strain of E. coli APEC_O2 is resistant towards multiple antimicrobials, however, no (complete) antibiotic resistance genes were present on the chromosome, but a number of genes associated with extra-intestinal disease were identified. Together, the information provided here on E. coli APEC_O2 will assist in future studies of avian pathogenic E. coli strains, in particular regarding strain of E. coli APEC_O2, and aid in the general understanding of the pathogenesis of avian pathogenic E. coli .

Awareness regarding preventive measures of avian influenza among the adult people of Thimi Municipality, Nepal.

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Manandhar, K; Chataut, J; Khanal, K; Shrestha, A; Shrestha, S; Shrestha, S

2013-01-01

Avian influenza is considered as a threat to global public health. Prevention and control depends on the awareness of the general population as well as high risk-groups. The avian influenza should be viewed more seriously because it may lead to pandemic influenza when the virus mutates its strain with the common human influenza. Thus, this study aims to explore the awareness regarding preventive measures of avian influenza among the adult population of Thimi Municipality. The objective of this study was to explore awareness regarding preventive measures of avian influenza among the adult population of Thimi Municipality. It is a cross-sectional, population based study. It was carried out in Thimi Municipality from May 15 to June 15, 2012. Pre tested structured questionnaire was used for face to face interview with randomly selected 250 subjects. Out of 250 subjects, 123 (49.2 %) were males. The mean age of subjects was 36 ± 11.8 year. Among total subjects, 94.4 percent had heard about avian influenza. The main source of information was television (94.1%). Majority of subjects (84.9 %) thought that keeping infected birds and poultry as the mode of transmission followed by eating not well cooked poultry meat (82.8 %). Out of total study subjects, 165 (66.0 percent) mentioned fever and 138 (55.2 percent) thought fatigue as the signs and symptoms. As for knowledge about preventive measures, majority (85.6%) stated that cleaning the surfaces that had come in contact with the poultry could prevent the disease and 83.2 % had knowledge that the infection could be prevented by washing hands with soap and water after poultry handling. Awareness regarding preventive measures was found significantly low in females, middle adults, illiterates, and house wives. The awareness regarding avian influenza was quite satisfactory among the adult people of Thimi Municipality. However level of awareness was seen lower in female, illiterate and middle adult. So that along with large

Detection of Evolutionarily Distinct Avian Influenza A Viruses in Antarctica

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Vijaykrishna, Dhanasekaran; Butler, Jeffrey; Baas, Chantal; Maurer-Stroh, Sebastian; Silva-de-la-Fuente, M. Carolina; Medina-Vogel, Gonzalo; Olsen, Bjorn; Kelso, Anne; Barr, Ian G.; González-Acuña, Daniel

2014-01-01

ABSTRACT Distinct lineages of avian influenza viruses (AIVs) are harbored by spatially segregated birds, yet significant surveillance gaps exist around the globe. Virtually nothing is known from the Antarctic. Using virus culture, molecular analysis, full genome sequencing, and serology of samples from Adélie penguins in Antarctica, we confirmed infection by H11N2 subtype AIVs. Their genetic segments were distinct from all known contemporary influenza viruses, including South American AIVs, suggesting spatial separation from other lineages. Only in the matrix and polymerase acidic gene phylogenies did the Antarctic sequences form a sister relationship to South American AIVs, whereas distant phylogenetic relationships were evident in all other gene segments. Interestingly, their neuraminidase genes formed a distant relationship to all avian and human influenza lineages, and the polymerase basic 1 and polymerase acidic formed a sister relationship to the equine H3N8 influenza virus lineage that emerged during 1963 and whose avian origins were previously unknown. We also estimated that each gene segment had diverged for 49 to 80 years from its most closely related sequences, highlighting a significant gap in our AIV knowledge in the region. We also show that the receptor binding properties of the H11N2 viruses are predominantly avian and that they were unable to replicate efficiently in experimentally inoculated ferrets, suggesting their continuous evolution in avian hosts. These findings add substantially to our understanding of both the ecology and the intra- and intercontinental movement of Antarctic AIVs and highlight the potential risk of an incursion of highly pathogenic AIVs into this fragile environment. PMID:24803521

Avian Influenza (Bird Flu)

Science.gov (United States)

... type="submit" value="Submit" /> Archived Flu Emails Influenza Types Seasonal Avian Swine Variant Pandemic Other Information on Avian Influenza Language: English (US) Español Recommend on Facebook Tweet ...

Emergence of a novel avian pox disease in British tit species.

Science.gov (United States)

Lawson, Becki; Lachish, Shelly; Colvile, Katie M; Durrant, Chris; Peck, Kirsi M; Toms, Mike P; Sheldon, Ben C; Cunningham, Andrew A

2012-01-01

Avian pox is a viral disease with a wide host range. In Great Britain, avian pox in birds of the Paridae family was first diagnosed in a great tit (Parus major) from south-east England in 2006. An increasing number of avian pox incidents in Paridae have been reported each year since, indicative of an emergent infection. Here, we utilise a database of opportunistic reports of garden bird mortality and morbidity to analyse spatial and temporal patterns of suspected avian pox throughout Great Britain, 2006-2010. Reports of affected Paridae (211 incidents) outnumbered reports in non-Paridae (91 incidents). The majority (90%) of Paridae incidents involved great tits. Paridae pox incidents were more likely to involve multiple individuals (77.3%) than were incidents in non-Paridae hosts (31.9%). Unlike the small wart-like lesions usually seen in non-Paridae with avian pox in Great Britain, lesions in Paridae were frequently large, often with an ulcerated surface and caseous core. Spatial analyses revealed strong clustering of suspected avian pox incidents involving Paridae hosts, but only weak, inconsistent clustering of incidents involving non-Paridae hosts. There was no spatial association between Paridae and non-Paridae incidents. We documented significant spatial spread of Paridae pox from an origin in south-east England; no spatial spread was evident for non-Paridae pox. For both host clades, there was an annual peak of reports in August/September. Sequencing of the avian poxvirus 4b core protein produced an identical viral sequence from each of 20 great tits tested from Great Britain. This sequence was identical to that from great tits from central Europe and Scandinavia. In contrast, sequence variation was evident amongst virus tested from 17 non-Paridae hosts of 5 species. Our findings show Paridae pox to be an emerging infectious disease in wild birds in Great Britain, apparently originating from viral incursion from central Europe or Scandinavia.

Emergence of a novel avian pox disease in British tit species.

Directory of Open Access Journals (Sweden)

Becki Lawson

Full Text Available Avian pox is a viral disease with a wide host range. In Great Britain, avian pox in birds of the Paridae family was first diagnosed in a great tit (Parus major from south-east England in 2006. An increasing number of avian pox incidents in Paridae have been reported each year since, indicative of an emergent infection. Here, we utilise a database of opportunistic reports of garden bird mortality and morbidity to analyse spatial and temporal patterns of suspected avian pox throughout Great Britain, 2006-2010. Reports of affected Paridae (211 incidents outnumbered reports in non-Paridae (91 incidents. The majority (90% of Paridae incidents involved great tits. Paridae pox incidents were more likely to involve multiple individuals (77.3% than were incidents in non-Paridae hosts (31.9%. Unlike the small wart-like lesions usually seen in non-Paridae with avian pox in Great Britain, lesions in Paridae were frequently large, often with an ulcerated surface and caseous core. Spatial analyses revealed strong clustering of suspected avian pox incidents involving Paridae hosts, but only weak, inconsistent clustering of incidents involving non-Paridae hosts. There was no spatial association between Paridae and non-Paridae incidents. We documented significant spatial spread of Paridae pox from an origin in south-east England; no spatial spread was evident for non-Paridae pox. For both host clades, there was an annual peak of reports in August/September. Sequencing of the avian poxvirus 4b core protein produced an identical viral sequence from each of 20 great tits tested from Great Britain. This sequence was identical to that from great tits from central Europe and Scandinavia. In contrast, sequence variation was evident amongst virus tested from 17 non-Paridae hosts of 5 species. Our findings show Paridae pox to be an emerging infectious disease in wild birds in Great Britain, apparently originating from viral incursion from central Europe or Scandinavia.

Avian disease at the Salton Sea

Science.gov (United States)

Friend, M.

2002-01-01

A review of existing records and the scientific literature was conducted for occurrences of avian diseases affecting free-ranging avifauna within the Salton Sea ecosystem. The period for evaluation was 1907 through 1999. Records of the U.S. Department of Agriculture, Bureau of Biological Survey and the scientific literature were the data sources for the period of 1907a??1939. The narrative reports of the U.S. Fish and Wildlife Service's Sonny Bono National Wildlife Refuge Complex and the epizootic database of the U.S. Geological Survey's National Wildlife Health Center were the primary data sources for the remainder of the evaluation. The pattern of avian disease at the Salton Sea has changed greatly over time. Relative to past decades, there was a greater frequency of major outbreaks of avian disease at the Salton Sea during the 1990s than in previous decades, a greater variety of disease agents causing epizootics, and apparent chronic increases in the attrition of birds from disease. Avian mortality was high for about a decade beginning during the mid-1920s, diminished substantially by the 1940s and was at low to moderate levels until the 1990s when it reached the highest levels reported. Avian botulism (Clostridium botulinum type C) was the only major cause of avian disease until 1979 when the first major epizootic of avian cholera (Pasteurella multocidia) was documented. Waterfowl and shorebirds were the primary species affected by avian botulism. A broader spectrum of species have been killed by avian cholera but waterfowl have suffered the greatest losses. Avian cholera reappeared in 1983 and has joined avian botulism as a recurring cause of avian mortality. In 1989, avian salmonellosis (Salmonella typhimurium) was first diagnosed as a major cause of avian disease within the Salton Sea ecosystem and has since reappeared several times, primarily among cattle egrets (Bubulcus ibis). The largest loss from a single epizootic occurred in 1992, when an estimated

Engineering of avian influenza virus detection system in a patient's body

International Nuclear Information System (INIS)

Budi Santoso; Romadhon; Sukandar, Istofa

2010-01-01

The avian influenza virus detection equipment in a patient's body has been made. Currently, detection of avian influenza virus carried out by expensive laboratory equipment's, so only certain hospitals can perform this detection. This developing equipment is expected to be cheaper than existing equipment and the diagnosis can be known immediately. The sensing device is made using the principle of nuclear radiation detection. Radiation comes from a drunk labelled tamiflu (oseltamivir) which is drunk to the patient. Tamiflu is a drug to catch H5N1 viruses in a patient's body. A labelled tamiflu is tamiflu which is labelled by 1-131 radioisotopes. The presence of virus in the body is proportional to the amount of radiation captured by the detector. The equipment is composed of a Geiger-Mueller (GM) pancake detector type, a signal processor, a counter, and a data processor (computer). The GM detector converts the radiation that comes into electrical signals. Electrical signal is then converted into TTL level pulses by the signal processor. Pulse counting results are processed by data processor. The total count is proportional to the amount of virus captured by labelled tamiflu. The measurement threshold can be set by medical officer through software. At a certain threshold can be inferred identified patients infected with avian influenza virus. If the measurement below the threshold means that the patient is still within safe limits. This equipment is expected to create avian influenza virus detection system that cheaply and quickly so that more and more hospitals are using to detect the avian influenza virus. (author)

Effects of cyclosporin A induced T-lymphocyte depletion on the course of avian Metapneumovirus (aMPV) infection in turkeys.

Science.gov (United States)

Rubbenstroth, Dennis; Dalgaard, Tina S; Kothlow, Sonja; Juul-Madsen, Helle R; Rautenschlein, Silke

2010-05-01

The avian Metapneumovirus (aMPV) causes an economically important acute respiratory disease in turkeys (turkey rhinotracheitis, TRT). While antibodies were shown to be insufficient for protection against aMPV-infection, the role of T-lymphocytes in the control of aMPV-infection is not clear. In this study we investigated the role of T-lymphocytes in aMPV-pathogenesis in a T-cell-suppression model in turkeys. T-cell-intact turkeys and turkeys partly depleted of functional CD4(+) and CD8(+) T-lymphocytes by Cyclosporin A (CsA) treatment were inoculated with the virulent aMPV subtype A strain BUT 8544. CsA-treatment resulted in a significant reduction of absolute numbers of circulating CD4(+) and CD8alpha(+) T-lymphocytes by up to 82 and 65%, respectively (P<0.05). Proportions of proliferating T-cells within mitogen-stimulated peripheral blood mononuclear cells were reduced by similar levels in CsA-treated birds compared to untreated controls (P<0.05). CsA-treated turkeys showed delayed recovery from aMPV-induced clinical signs and histopathological lesions and a prolonged detection of aMPV in choanal swabs. The results of this study show that T-lymphocytes play an important role in the control of primary aMPV-infection in turkeys. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Tenacity of low-pathogenic avian influenza viruses in different types of poultry litter.

Science.gov (United States)

Reis, A; Stallknecht, D; Ritz, C; García, M

2012-08-01

To determine the risk of infection associated with exposure to low-pathogenic avian influenza (AI) virus-contaminated poultry litter, the tenacity of low pathogenic A/Ck/CA/431/00(H6N2), A/Mallard/MN/355779/00(H5N2), and A/turkey/Ohio/313053/04(H3N2) was evaluated. Viral stocks were incubated with poultry litter from commercial flocks at 25°C. Three types of poultry litter, wood shavings, shavings plus gypsum, and shavings plus peanut hulls, from commercial broiler flocks were used. The 3 low-pathogenic avian influenza viruses retained infectivity for one day in wood shavings and shavings plus peanut hulls litter types, whereas in wood shavings plus gypsum, litter viruses remained infective for up to 3 d. In contrast to the survivability in litter, all the viruses maintained infectivity in water for 4 d at titers of log(10)4.5. The infectivity of A/Ck/CA/431/00(H6N2) shed by experimentally infected layers, broilers, and turkeys was retained for one day, independently of the type of litter. In commercial production where a high density of birds are housed, the viral load shed by an infected flock will be significantly higher than the viral load shed 3 d postinfection obtained under the experimental conditions used in this study. Therefore proper management and disposal of poultry by products, such as windrow composting of litter and the composting of carcasses during an AI outbreak should be implemented.

Structure and receptor binding preferences of recombinant hemagglutinins from avian and human H6 and H10 influenza A virus subtypes.

Science.gov (United States)

Yang, Hua; Carney, Paul J; Chang, Jessie C; Villanueva, Julie M; Stevens, James

2015-04-01

During 2013, three new avian influenza A virus subtypes, A(H7N9), A(H6N1), and A(H10N8), resulted in human infections. While the A(H7N9) virus resulted in a significant epidemic in China across 19 provinces and municipalities, both A(H6N1) and A(H10N8) viruses resulted in only a few human infections. This study focuses on the major surface glycoprotein hemagglutinins from both of these novel human viruses. The detailed structural and glycan microarray analyses presented here highlight the idea that both A(H6N1) and A(H10N8) virus hemagglutinins retain a strong avian receptor binding preference and thus currently pose a low risk for sustained human infections. Human infections with zoonotic influenza virus subtypes continue to be a great public health concern. We report detailed structural analysis and glycan microarray data for recombinant hemagglutinins from A(H6N1) and A(H10N8) viruses, isolated from human infections in 2013, and compare them with hemagglutinins of avian origin. This is the first structural report of an H6 hemagglutinin, and our results should further the understanding of these viruses and provide useful information to aid in the continuous surveillance of these zoonotic influenza viruses. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Pathogenesis of Highly Pathogenic Avian Influenza (HPAI) A/turkey/Turkey/1/2005 H5N1 in Pekin ducks (Anas platyrhynchos) infected experimentally

OpenAIRE

Löndt , Brandon Z.; Nunez , Alejandro; Banks , Jill; Nili , Hassan; Johnson , Linda K; Alexander , Dennis

2008-01-01

Abstract Asian H5N1 (hereafter referred to as panzootic H5N1) highly pathogenic avian influenza (HPAI) virus has caused large numbers of deaths in both poultry and wild bird populations. Recent isolates of this virus have been reported to cause disease and death in commercial ducks, which has not been seen with other HPAI viruses. However, little is known about the dissemination of this H5N1 within the organs and the cause of death in infected ducks. Nineteen 4-week-old Pekin ducks...

Seroprevalence survey of avian influenza A (H5) in wild migratory birds in Yunnan Province, Southwestern China.

Science.gov (United States)

Chang, Hua; Dai, Feiyan; Liu, Zili; Yuan, Feizhou; Zhao, Siyue; Xiang, Xun; Zou, Fengcai; Zeng, Bangquan; Fan, Yating; Duan, Gang

2014-02-03

Highly pathogenic avian influenza virus (HPAIV) is a highly contagious disease which is a zoonotic pathogen of significant economic and public health concern. The outbreaks caused by HPAIV H5N1 of Asian origin have caused animal and human disease and mortality in several countries of Southeast Asia, such as Bangladesh, Cambodia, China, India, Indonesia, Laos, Myanmar, Thailand and Viet Nam. For the first time since 1961, this HPAIV has also caused extensive mortality in wild birds and has sparked debate of the role wild birds have played in the spread of this virus. Other than confirmed mortality events, little is known of this virus in wild birds. There is no report on the seroprevalence of avian influenza H5 infection in wild migratory birds in Yunnan Province. In this study we examined live wild birds in Yunnan Province for H5 specific antibody to better understand the occurrence of this disease in free living birds. Sera from 440 wild birds were collected from in Kunming and Northern Ailaoshan of Yunnan Province, Southwestern China, and assayed for H5 antibodies using the hemagglutination inhibition (HI) assays. The investigation revealed that the seroprevalence of avian influenza H5 was as following: Ciconiiformes 2.6%, Strigiformes 13.04%, Passeriformes 20%, Cuculiformes 21.74%, Gruiformes 0%, Columbiformes 0%, Charadriiformes 0% and Coraciiformes 0%. Statistical analyses showed that there was a significant difference of prevalence between the orders (P avian influenza H5 antibodies were detected in 23 of 440 (5.23%) sera. Mean HI titer 23 positive sera against H5 were 5.4 log₂. The results of the present survey indicated that the proportion of wild birds had previously infected AIV H5 at other times of the year. To our knowledge, this is the first seroprevalence report of avian influenza H5 infection in wild migratory birds in China' s southwestern Yunnan Province. The results of the present survey have significant public health concerns.

AN EPIZOOTIC OF EMERGING NOVEL AVIAN POX IN CARRION CROWS (CORVUS CORONE) AND LARGE-BILLED CROWS (CORVUS MACRORHYNCHOS) IN JAPAN.

Science.gov (United States)

Fukui, Daisuke; Nakamura, Makiko; Yamaguchi, Tsuyoshi; Takenaka, Makiko; Murakami, Mami; Yanai, Tokuma; Fukushi, Hideto; Yanagida, Kazumi; Bando, Gen; Matsuno, Keita; Nagano, Masashi; Tsubota, Toshio

2016-04-28

In 2006-10, an epizootic of emerging avian pox occurred in Carrion Crows ( Corvus corone ) and Large-billed Crows ( Corvus macrorhynchos ), leading to mortality of juvenile crows in Hokkaido, the northernmost island of Japan. We diagnosed 27 crows with proliferative skin lesions (19 carcasses and eight biopsied cases [one in zoo captivity]) as avian pox clinically, histopathologically by detection of Avipoxvirus-specific 4b core protein (P4b) gene, and epidemiologically. The fatal cases demonstrated intensively severe infection and aggressive lesions with secondary bacterial infection. Since the first identification of avian pox in Sapporo, Japan, in 2006, the frequency of mortality events has increased, peaking in 2007-08. Mortalities have subsequently occurred in other areas, suggesting disease expansion. In Sapporo, prevalence of avian pox evaluated by field censuses during 2007-12 was 17.6% (6.6-27.2%), peaked during 2007-08 and 2008-09, and then decreased. All diseased crows were juveniles, except for one adult. The number of crows assembling in the winter roosts had been stable for >10 yr; however, it declined in 2007-08, decreased by about 50% in 2008-09, and recovered to the previous level in 2009-10, correlated with the avian pox outbreak. Thus, avian pox probably contributed to the unusual crow population decline. All P4b sequences detected in six specimens in Sapporo were identical and different from any previously reported sequences. The sequence detected in the zoo-kept crow was distinct from any reported clades, and interspecies transmission was suspected. This report demonstrates an emerging novel avian pox in the Japanese avifauna and in global populations of Carrion Crows and Large-billed Crows. Longitudinal monitoring is needed to evaluate its impact on the crow population.

H9N2 low pathogenic avian influenza in Pakistan (2012-2015)

Science.gov (United States)

Significant economic losses from deaths and decreased egg production have resulted from H9N2 low pathogenic avian influenza virus (LPAIV) infections in poultry across North Africa, the Middle East and Asia. The H9N2 LPAIVs have been endemic in Pakistani poultry since 1996, but no new viruses have be...

Avian respiratory system disorders

Science.gov (United States)

Olsen, Glenn H.

1989-01-01

Diagnosing and treating respiratory diseases in avian species requires a basic knowledge about the anatomy and physiology of this system in birds. Differences between mammalian and avian respiratory system function, diagnosis, and treatment are highlighted.

Hepatozoon ellisgreineri n. sp. (Hepatozoidae): description of the first avian apicomplexan blood parasite inhabiting granulocytes.

Science.gov (United States)

Valkiūnas, Gediminas; Mobley, Kristin; Iezhova, Tatjana A

2016-02-01

Blood parasites of the genus Hepatozoon (Apicomplexa, Hepatozoidae) infect all groups of terrestrial vertebrates, and particularly high prevalence and species diversity have been reported in reptiles and mammals. A few morphologically similar species, in which gamonts inhabit mononuclear leukocytes and red blood cells, have been described in birds. Here, we report a new Hepatozoon species, which was found in wild-caught secretary birds Sagittarius serpentarius, from Tanzania. Hepatozoon ellisgreineri n. sp. can be readily distinguished from all described species of avian Hepatozoon because its gamonts develop only in granulocytes, predominantly in heterophils, a unique characteristic among bird parasites of this genus. Additionally, this is the first reported avian apicomplexan blood parasite, which inhabits and matures in granulocytes. We describe H. ellisgreineri based on morphological characteristics of blood stages and their host cells. This finding broadens knowledge about host cells of avian Hepatozoon spp. and other avian apicomplexan blood parasites, contributing to the better understanding of the diversity of haematozoa. This is the first report of hepatozoonosis in endangered African birds of the Sagittariidae.

Avian Pox Discovered in the Critically Endangered Waved Albatross (Phoebastria irrorata) from the Galápagos Islands, Ecuador.

Science.gov (United States)

Tompkins, Emily M; Anderson, David J; Pabilonia, Kristy L; Huyvaert, Kathryn P

2017-10-01

The Waved Albatross (Phoebastria irrorata) is a critically endangered seabird in a rapidly shrinking population in the Galápagos Islands, Ecuador. The introduction of novel pathogens and parasites poses a threat to population persistence. Monitoring disease prevalence and guarding against the spread of such agents in endemic taxa are conservation priorities for the Galápagos, where recent increases in the prevalence of avian pox may have contributed to population declines and range contractions in other bird species. During November 2013-January 2014, we identified 14 Waved Albatross nestlings at our study site on Española Island with avian pox-like lesions and clinical signs. Other seabirds, landbirds, and adult Waved Albatrosses were apparently unaffected. Histopathology of tissue samples from five infected nestlings revealed inclusion bodies in all samples, consistent with avipoxvirus infection. We documented higher mortality (6 of 14 nestlings) in affected nestlings than in unaffected young in this small outbreak of avian pox, the first report of its kind in the world's only tropical albatross.

Avian influenza H7N9/13 and H7N7/13: a comparative virulence study in chickens, pigeons, and ferrets.

Science.gov (United States)

Kalthoff, Donata; Bogs, Jessica; Grund, Christian; Tauscher, Kerstin; Teifke, Jens P; Starick, Elke; Harder, Timm; Beer, Martin

2014-08-01

Human influenza cases caused by a novel avian H7N9 virus in China emphasize the zoonotic potential of that subtype. We compared the infectivity and pathogenicity of the novel H7N9 virus with those of a recent European avian H7N7 strain in chickens, pigeons, and ferrets. Neither virus induced signs of disease despite substantial replication in inoculated chickens and rapid transmission to contact chickens. Evidence of the replication of both viruses in pigeons, albeit at lower levels of RNA excretion, was also detected. No clear-cut differences between the two H7 isolates emerged regarding replication and antibody development in avian hosts. In ferrets, in contrast, greater replication of the avian H7N9 virus than of the H7N7 strain was observed with significant differences in viral presence, e.g., in nasal wash, lung, and cerebellum samples. Importantly, both viruses showed the potential to spread to the mammal brain. We conclude that efficient asymptomatic viral replication and shedding, as shown in chickens, facilitate the spread of H7 viruses that may harbor zoonotic potential. Biosafety measures are required for the handling of poultry infected with avian influenza viruses of the H7 subtype, independently of their pathogenicity for gallinaceous poultry. This study is important to the field since it provides data about the behavior of the novel H7N9 avian influenza virus in chickens, pigeons, and ferrets in comparison with that of a recent low-pathogenicity H7N7 strain isolated from poultry. We clearly show that chickens, but not pigeons, are highly permissive hosts of both H7 viruses, allowing high-titer replication and virus shedding without any relevant clinical signs. In the ferret model, the potential of both viruses to infect mammals could be demonstrated, including infection of the brain. However, the replication efficiency of the H7N9 virus in ferrets was higher than that of the H7N7 strain. In conclusion, valuable data for the risk analysis of low

Respiratory immune responses in the chicken; Towards development of mucosal avian influenza virus vaccines

NARCIS (Netherlands)

de Geus, E.D.

2012-01-01

Several important poultry pathogens, including avian influenza virus (AIV), enter the host through the mucosae of the respiratory tract (RT) and subsequently disseminate towards other organs in the body. Therefore, animal health significantly depends on the control of infection in the lung tissue by

76 FR 24793 - Highly Pathogenic Avian Influenza

Science.gov (United States)

2011-05-03

.... APHIS-2006-0074] RIN 0579-AC36 Highly Pathogenic Avian Influenza AGENCY: Animal and Plant Health... any subtype of highly pathogenic avian influenza is considered to exist. The interim rule also imposed... avian influenza, or that have moved through regions where any subtype of highly pathogenic avian...

Metapneumovirus infections

Science.gov (United States)

Avian metapneumovirus (aMPV) causes turkey rhinotracheitis (TRT), an acute upper respiratory tract infection of turkeys, and is also associated with swollen head syndrome (SHS) in chickens and egg production losses in layers. Since the first TRT reported in the late 1970s in South Africa, the virus...

Standardization of an inactivated H17N1 avian influenza vaccine and efficacy against A/Chicken/Italy/13474/99 high-pathogenicity virus infection.

Science.gov (United States)

Di Trani, L; Cordioli, P; Falcone, E; Lombardi, G; Moreno, A; Sala, G; Tollis, M

2003-01-01

The minimum requirements for assessing the immunogenicity of an experimental avian influenza (AI) vaccine prepared from inactivated A/Turkey/Italy/2676/99 (H7N1) low-pathogenicity (LP) AI (LPAI) virus were determined in chickens of different ages. A correlation between the amount of hemagglutinin (HA) per dose of vaccine and the protection against clinical signs of disease and infection by A/Chicken/Italy/13474/99 highly pathogenic (HP) AI (HPAI) virus was established. Depending on the vaccination schedule, one or two administrations of 0.5 microg of hemagglutinin protected chickens against clinical signs and death and completely prevented virus shedding from birds challenged at different times after vaccination.

A review of highly pathogenic avian influenza in birds, with an emphasis on Asian H5N1 and recommendations for prevention and control.

Science.gov (United States)

Kelly, Terra R; Hawkins, Michelle G; Sandrock, Christian E; Boyce, Walter M

2008-03-01

Avian influenza is a disease of both veterinary and public health importance. Influenza A viruses infect a range of hosts, including humans, and can cause significant morbidity and mortality. These viruses have high genetic variability, and new strains develop through both mutation and reassortment. Modes of transmission as well as the location of viral shedding may differ both by host species and by viral strain. Clinical signs of influenza A virus infection in birds vary considerably depending on the viral subtype, environmental factors, and age, health status, and species of the bird and range from decreased egg production and gastrointestinal manifestations to nervous system disorders and respiratory signs. Most commonly, peracute death with minimal clinical disease is observed in poultry infected with a highly pathogenic avian influenza virus. There are various prevention and control strategies for avian influenza, including education, biosecurity, surveillance, culling of infected animals, and vaccination. These strategies will differ by institution and current federal regulations. Each institution should have an established biosecurity protocol that can be properly instituted. Lastly, human health precautions, such as proper hand hygiene, personal protective equipment, and employee health monitoring, are imperative for at-risk individuals.

Experimental infection with highly pathogenic H5N8 avian influenza viruses in the Mandarin duck (Aix galericulata) and domestic pigeon (Columba livia domestica).

Science.gov (United States)

Kwon, Jung-Hoon; Noh, Yun Kyung; Lee, Dong-Hun; Yuk, Seong-Su; Erdene-Ochir, Tseren-Ochir; Noh, Jin-Yong; Hong, Woo-Tack; Jeong, Jei-Hyun; Jeong, Sol; Gwon, Gyeong-Bin; Song, Chang-Seon; Nahm, Sang-Soep

2017-05-01

Wild birds play a major role in the evolution, maintenance, and dissemination of highly pathogenic avian influenza viruses (HPAIV). Sub-clinical infection with HPAI in resident wild birds could be a source of dissemination of HPAIV and continuous outbreaks. In this study, the pathogenicity and infectivity of two strains of H5N8 clade 2.3.4.4 virus were evaluated in the Mandarin duck (Aix galericulata) and domestic pigeon (Columba livia domestica). None of the birds experimentally infected with H5N8 viruses showed clinical signs or mortality. The H5N8 viruses efficiently replicated in the virus-inoculated Mandarin ducks and transmitted to co-housed Mandarin ducks. Although relatively high levels of viral shedding were noted in pigeons, viral shedding was not detected in some of the pigeons and the shedding period was relatively short. Furthermore, the infection was not transmitted to co-housed pigeons. Immunohistochemical examination revealed the presence of HPAIV in multiple organs of the infected birds. Histopathological evaluation showed the presence of inflammatory responses primarily in HPAIV-positive organs. Our results indicate that Mandarin ducks and pigeons can be infected with H5N8 HPAIV without exhibiting clinical signs; thus, they may be potential healthy reservoirs of the H5N8 HPAIV. Copyright © 2017 Elsevier B.V. All rights reserved.

In vitro antiviral activity of chestnut and quebracho woods extracts against avian reovirus and metapneumovirus.

Science.gov (United States)

Lupini, C; Cecchinato, M; Scagliarini, A; Graziani, R; Catelli, E

2009-12-01

Field evidences have suggested that a natural extract, containing tannins, could be effective against poultry enteric viral infections. Moreover previous studies have shown that vegetable tannins can have antiviral activity against human viruses. Based on this knowledge three different Chestnut (Castanea spp.) wood extracts and one Quebracho (Schinopsis spp.) wood extract, all containing tannins and currently used in the animal feed industry, were tested for in vitro antiviral activity against avian reovirus (ARV) and avian metapneumovirus (AMPV). The MTT assay was used to evaluate the 50% cytotoxic compounds concentration (CC(50)) on Vero cells. The antiviral properties were tested before and after the adsorption of the viruses to Vero cells. Antiviral activities were expressed as IC(50) (concentration required to inhibit 50% of viral cytopathic effect). CC(50)s of tested compounds were > 200 microg/ml. All compounds had an extracellular antiviral effect against both ARV and AMPV with IC(50) values ranging from 25 to 66 microg/ml. Quebracho extract had also evident intracellular anti-ARV activity (IC(50) 24 microg/ml). These preliminary results suggest that the examined vegetable extracts might be good candidates in the control of some avian virus infections. Nevertheless further in vivo experiments are required to confirm these findings.

IL-17A regulates Eimeria tenella schizont maturation and migration in avian coccidiosis

Science.gov (United States)

Although IL17A is associated with the immunological control of various infectious diseases, its role in host response to Eimeria infections is not well understood. In an effort to better dissect the role of IL17A in host-pathogen interactions in avian coccidiosis, a neutralizing antibody (Ab) to chi...

Mitigation strategies to reduce the generation and transmission of airborne highly pathogenic avian influenza virus particles during processing of infected poultry.

Science.gov (United States)

Bertran, Kateri; Clark, Andrew; Swayne, David E

2018-06-08

Airborne transmission of H5N1 highly pathogenic avian influenza (HPAI) viruses has occurred among poultry and from poultry to humans during home or live-poultry market slaughter of infected poultry, and such transmission has been experimentally reproduced. In this study, we investigated simple, practical changes in the processing of H5N1 virus-infected chickens to reduce infectious airborne particles and their transmission. Our findings suggest that containing the birds during the killing and bleeding first step by using a disposable plastic bag, a commonly available cooking pot widely used in Egypt (halla), or a bucket significantly reduces generation of infectious airborne particles and transmission to ferrets. Similarly, lack of infectious airborne particles was observed when processing vaccinated chickens that had been challenged with HPAI virus. Moreover, the use of a mechanical defeatherer significantly increased total number of particles in the air compared to manual defeathering. This study confirms that simple changes in poultry processing can efficiently mitigate generation of infectious airborne particles and their transmission to humans. Published by Elsevier GmbH.

Population Dynamics and Rates of Molecular Evolution of a Recently Emerged Paramyxovirus, Avian Metapneumovirus Subtype C▿ †

OpenAIRE

Padhi, Abinash; Poss, Mary

2008-01-01

We report the existence of two distinct sublineages of avian metapneumovirus (MPV) subtype C, a virus which has caused serious economic loss in commercial turkey farms in the United States. This subtype is closely related to human MPV, infects multiple avian species, and is globally distributed. The evolutionary rates of this virus are estimated to be 1.3 × 10−3 to 7 × 10−3 substitutions per site per year, and coalescent estimates place its emergence between 1991 and 1996. The four genes exam...

Mapping the risk of avian influenza in wild birds in the US

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Trevon L. Fuller; Sassan S. Saatchi; Emily E. Curd; Erin Toffelmier; Henri A. Thomassen; Wolfgang Buermann; David F. DeSante; Mark P. Nott; James F. Saracco; C. J. Ralph; John D. Alexander; John P. Pollinger; Thomas B. Smith.

2010-01-01

Avian influenza virus (AIV) is an important public health issue because pandemic influenza viruses in people have contained genes from viruses that infect birds. The H5 and H7 AIV subtypes have periodically mutated from low pathogenicity to high pathogenicity form. Analysis of the geographic distribution of AIV can identify areas where reassortment events might occur...

CLINICAL EFFECT OF HEMOPARASITE INFECTIONS IN SNOWY OWLS ( BUBO SCANDIACUS).

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Baker, Kendra C; Rettenmund, Christy L; Sander, Samantha J; Rivas, Anne E; Green, Kaitlin C; Mangus, Lisa; Bronson, Ellen

2018-03-01

Vector-borne hemoparasites are commonly found in avian species. Plasmodium spp., the causative agent of avian malaria, are intraerythrocytic parasites that can cause signs ranging from subclinical infection to severe acute disease. In raptor species, most hemoparasites are associated with subclinical infection and are generally not treated when seen on blood evaluation. This case series reviews five cases of hemoparasite infection in snowy owls ( Bubo scandiacus). These animals were infected with a variety of hemoparasites, including Plasmodium, Haemoproteus, and Leukocytozoon spp. Death of one of these birds due to hemoparasite burden led to a change in the monitoring for and treatment of subclinical hemoparasitic infections in this species. Three subsequently infected snowy owls have been treated with primaquine and chloroquine. The birds that were treated survived infection, and parasite burdens in peripheral blood diminished. Postulated reasons for increased morbidity and mortality associated with hemoparasitic infections in captive snowy owls, as opposed to other raptor species, include stress, concurrent disease, novel pathogen exposure, and elevated environmental temperatures.

Oxyspirura petrowi infection leads to pathological consequences in Northern bobwhite (Colinus virginianus

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Nicholas R. Dunham

2016-12-01

Full Text Available Debilitating ocular diseases are often reported in avian species. By and large, helminth parasites have been overlooked in avian diseases and regarded as inconsequential. The decline of Northern bobwhite quail (Colinus virginianus in the Rolling Plains ecoregion of Texas has prompted an investigation of the factors influencing their disappearance. Infection by the eyeworm (Oxyspirura petrowi has been documented in many avian species; however, the effect it has on its host is not well understood. Heavy eyeworm infection has been documented in Northern bobwhites throughout this ecoregion, leading to eye pathology in this host species. The present study further documents and supports the pathological changes associated with O. petrowi in bobwhites.

Integrin αvβ1 Modulation Affects Subtype B Avian Metapneumovirus Fusion Protein-mediated Cell-Cell Fusion and Virus Infection.

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Yun, Bing-Ling; Guan, Xiao-Lu; Liu, Yong-Zhen; Zhang, Yao; Wang, Yong-Qiang; Qi, Xiao-Le; Cui, Hong-Yu; Liu, Chang-Jun; Zhang, Yan-Ping; Gao, Hong-Lei; Gao, Li; Li, Kai; Gao, Yu-Long; Wang, Xiao-Mei

2016-07-08

Avian metapneumovirus (aMPV) fusion (F) protein mediates virus-cell membrane fusion to initiate viral infection, which requires F protein binding to its receptor(s) on the host cell surface. However, the receptor(s) for aMPV F protein is still not identified. All known subtype B aMPV (aMPV/B) F proteins contain a conserved Arg-Asp-Asp (RDD) motif, suggesting that the aMPV/B F protein may mediate membrane fusion via the binding of RDD to integrin. When blocked with integrin-specific peptides, aMPV/B F protein fusogenicity and viral replication were significantly reduced. Specifically we identified integrin αv and/or β1-mediated F protein fusogenicity and viral replication using antibody blocking, small interfering RNAs (siRNAs) knockdown, and overexpression. Additionally, overexpression of integrin αv and β1 in aMPV/B non-permissive cells conferred aMPV/B F protein binding and aMPV/B infection. When RDD was altered to RAE (Arg-Ala-Glu), aMPV/B F protein binding and fusogenic activity were profoundly impaired. These results suggest that integrin αvβ1 is a functional receptor for aMPV/B F protein-mediated membrane fusion and virus infection, which will provide new insights on the fusogenic mechanism and pathogenesis of aMPV. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Integrin αvβ1 Modulation Affects Subtype B Avian Metapneumovirus Fusion Protein-mediated Cell-Cell Fusion and Virus Infection*

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Yun, Bing-Ling; Guan, Xiao-Lu; Liu, Yong-Zhen; Zhang, Yao; Wang, Yong-Qiang; Qi, Xiao-Le; Cui, Hong-Yu; Liu, Chang-Jun; Zhang, Yan-Ping; Gao, Hong-Lei; Gao, Li; Li, Kai; Gao, Yu-Long; Wang, Xiao-Mei

2016-01-01

Avian metapneumovirus (aMPV) fusion (F) protein mediates virus-cell membrane fusion to initiate viral infection, which requires F protein binding to its receptor(s) on the host cell surface. However, the receptor(s) for aMPV F protein is still not identified. All known subtype B aMPV (aMPV/B) F proteins contain a conserved Arg-Asp-Asp (RDD) motif, suggesting that the aMPV/B F protein may mediate membrane fusion via the binding of RDD to integrin. When blocked with integrin-specific peptides, aMPV/B F protein fusogenicity and viral replication were significantly reduced. Specifically we identified integrin αv and/or β1-mediated F protein fusogenicity and viral replication using antibody blocking, small interfering RNAs (siRNAs) knockdown, and overexpression. Additionally, overexpression of integrin αv and β1 in aMPV/B non-permissive cells conferred aMPV/B F protein binding and aMPV/B infection. When RDD was altered to RAE (Arg-Ala-Glu), aMPV/B F protein binding and fusogenic activity were profoundly impaired. These results suggest that integrin αvβ1 is a functional receptor for aMPV/B F protein-mediated membrane fusion and virus infection, which will provide new insights on the fusogenic mechanism and pathogenesis of aMPV. PMID:27226547

A novel recombinant retrovirus in the genomes of modern birds combines features of avian and mammalian retroviruses.

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Henzy, Jamie E; Gifford, Robert J; Johnson, Welkin E; Coffin, John M

2014-03-01

Endogenous retroviruses (ERVs) represent ancestral sequences of modern retroviruses or their extinct relatives. The majority of ERVs cluster alongside exogenous retroviruses into two main groups based on phylogenetic analyses of the reverse transcriptase (RT) enzyme. Class I includes gammaretroviruses, and class II includes lentiviruses and alpha-, beta-, and deltaretroviruses. However, analyses of the transmembrane subunit (TM) of the envelope glycoprotein (env) gene result in a different topology for some retroviruses, suggesting recombination events in which heterologous env sequences have been acquired. We previously demonstrated that the TM sequences of five of the six genera of orthoretroviruses can be divided into three types, each of which infects a distinct set of vertebrate classes. Moreover, these classes do not always overlap the host range of the associated RT classes. Thus, recombination resulting in acquisition of a heterologous env gene could in theory facilitate cross-species transmissions across vertebrate classes, for example, from mammals to reptiles. Here we characterized a family of class II avian ERVs, "TgERV-F," that acquired a mammalian gammaretroviral env sequence. Although TgERV-F clusters near a sister clade to alpharetroviruses, its genome also has some features of betaretroviruses. We offer evidence that this unusual recombinant has circulated among several avian orders and may still have infectious members. In addition to documenting the infection of a nongalliform avian species by a mammalian retrovirus, TgERV-F also underscores the importance of env sequences in reconstructing phylogenies and supports a possible role for env swapping in allowing cross-species transmissions across wide taxonomic distances. Retroviruses can sometimes acquire an envelope gene (env) from a distantly related retrovirus. Since env is a key determinant of host range, such an event affects the host range of the recombinant virus and can lead to the creation

Unique Determinants of Neuraminidase Inhibitor Resistance among N3, N7, and N9 Avian Influenza Viruses.

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Song, Min-Suk; Marathe, Bindumadhav M; Kumar, Gyanendra; Wong, Sook-San; Rubrum, Adam; Zanin, Mark; Choi, Young-Ki; Webster, Robert G; Govorkova, Elena A; Webby, Richard J

2015-11-01

Human infections with avian influenza viruses are a serious public health concern. The neuraminidase (NA) inhibitors (NAIs) are the frontline anti-influenza drugs and are the major option for treatment of newly emerging influenza. Therefore, it is essential to identify the molecular markers of NAI resistance among specific NA subtypes of avian influenza viruses to help guide clinical management. NAI-resistant substitutions in NA subtypes other than N1 and N2 have been poorly studied. Here, we identified NA amino acid substitutions associated with NAI resistance among influenza viruses of N3, N7, and N9 subtypes which have been associated with zoonotic transmission. We applied random mutagenesis and generated recombinant influenza viruses carrying single or double NA substitution(s) with seven internal genes from A/Puerto Rico/8/1934 (H1N1) virus. In a fluorescence-based NA inhibition assay, we identified three categories of NA substitutions associated with reduced inhibition by NAIs (oseltamivir, zanamivir, and peramivir): (i) novel subtype-specific substitutions in or near the enzyme catalytic site (R152W, A246T, and D293N, N2 numbering), (ii) subtype-independent substitutions (E119G/V and/or D and R292K), and (iii) substitutions previously reported in other subtypes (Q136K, I222M, and E276D). Our data show that although some markers of resistance are present across NA subtypes, other subtype-specific markers can only be determined empirically. The number of humans infected with avian influenza viruses is increasing, raising concerns of the emergence of avian influenza viruses resistant to neuraminidase (NA) inhibitors (NAIs). Since most studies have focused on NAI-resistance in human influenza viruses, we investigated the molecular changes in NA that could confer NAI resistance in avian viruses grown in immortalized monolayer cells, especially those of the N3, N7, and N9 subtypes, which have caused human infections. We identified not only numerous NAI

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.

Local and systemic immune responses following infection of broiler-type chickens with avian Metapneumovirus subtypes A and B.

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Rautenschlein, Silke; Aung, Ye Htut; Haase, Christine

2011-03-15

Infections with avian Metapneumovirus (aMPV) are often associated with swollen head syndrome in meat type chickens. Previous studies in turkeys have demonstrated that local humoral and cell-mediated immunity plays a role in aMPV-infection. Previous experimental and field observations indicated that the susceptibility of broilers and their immune reactions to aMPV may differ from turkeys. In the presented study local and systemic immune reactions of broilers were investigated after experimental infections with subtypes A and B aMPV of turkey origin. Both virus subtypes induced a mild respiratory disease. The recovery from respiratory signs correlated with the induction of local and systemic aMPV virus-neutralizing antibodies, which began to rise at 6 days post infection (dpi), when the peak of clinical signs was observed. In a different manner to the virus neutralizing (VN) and IgG-ELISA serum antibody titres, which showed high levels until the end of the experiments between 24 and 28 dpi, the specific IgA-ELISA and VN-antibody levels in tracheal washes decreased by 10 and 14 dpi, respectively, which may explain the recurring aMPV-infections in the field. Ex vivo cultured spleen cells from aMPV-infected broilers released at 3 and 6 dpi higher levels of IFN-γ after stimulation with Concanavalin A as compared to virus-free birds. In agreement with studies in turkeys, aMPV-infected broilers showed a clear CD4+ T cell accumulation in the Harderian gland (HG) at 6 dpi (P<0.05). In contrast to other investigations in turkeys aMPV-infected broilers showed an increase in the number of CD8alpha+ cells at 6 dpi compared to virus-free birds (P<0.05). The numbers of local B cells in the Harderian gland were not affected by the infection. Both aMPV A and B induced up-regulation of interferon (IFN)-γ mRNA-expression in the nasal turbinates, while in the Harderian gland only aMPV-A induced enhanced IFN-γ expression at 3 dpi. The differences in systemic and local T cell and

Avian dark cells

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Hara, J.; Plymale, D. R.; Shepard, D. L.; Hara, H.; Garry, Robert F.; Yoshihara, T.; Zenner, Hans-Peter; Bolton, M.; Kalkeri, R.; Fermin, Cesar D.

2002-01-01

Dark cells (DCs) of mammalian and non-mammalian species help to maintain the homeostasis of the inner ear fluids in vivo. Although the avian cochlea is straight and the mammalian cochlea is coiled, no significant difference in the morphology and/or function of mammalian and avian DCs has been reported. The mammalian equivalent of avian DCs are marginal cells and are located in the stria vascularis along a bony sheet. Avian DCs hang free from the tegmentum vasculosum (TV) of the avian lagena between the perilymph and endolymph. Frame averaging was used to image the fluorescence emitted by several fluorochromes applied to freshly isolated dark cells (iDCs) from chickens (Gallus domesticus) inner ears. The viability of iDCs was monitored via trypan blue exclusion at each isolation step. Sodium Green, BCECF-AM, Rhodamine 123 and 9-anthroyl ouabain molecules were used to test iDC function. These fluorochromes label iDCs ionic transmembrane trafficking function, membrane electrogenic potentials and Na+/K+ ATPase pump's activity. Na+/K+ ATPase pump sites, were also evaluated by the p-nitrophenyl phosphatase reaction. These results suggest that iDCs remain viable for several hours after isolation without special culturing requirements and that the number and functional activity of Na+/K+ ATPase pumps in the iDCs were indistinguishable from in vivo DCs. Primary cultures of freshly iDCs were successfully maintained for 28 days in plastic dishes with RPMI 1640 culture medium. The preparation of iDCs overcomes the difficulty of DCs accessability in vivo and the unavoidable contamination that rupturing the inner ear microenvironments induces.

Influenza A viruses of avian origin circulating in pigs and other mammals.

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Urbaniak, Kinga; Kowalczyk, Andrzej; Markowska-Daniel, Iwona

2014-01-01

Influenza A viruses (IAVs) are zoonotic agents, capable of crossing the species barriers. Nowadays, they still constitute a great challenge worldwide. The natural reservoir of all influenza A viruses are wild aquatic birds, despite the fact they have been isolated from a number of avian and mammalian species, including humans. Even when influenza A viruses are able to get into another than waterfowl population, they are often unable to efficiently adapt and transmit between individuals. Only in rare cases, these viruses are capable of establishing a new lineage. To succeed a complete adaptation and further transmission between species, influenza A virus must overcome a species barrier, including adaptation to the receptors of a new host, which would allow the virus-cell binding, virus replication and, then, animal-to-animal transmission. For many years, pigs were thought to be intermediate host for adaptation of avian influenza viruses to humans, because of their susceptibility to infection with both, avian and human influenza viruses, which supported hypothesis of pigs as a 'mixing vessel'. In this review, the molecular factors necessary for interspecies transmission are described, with special emphasis on adaptation of avian influenza viruses to the pig population. In addition, this review gives the information about swine influenza viruses circulating around the world with special emphasis on Polish strains.

Borna disease virus and its role in the pathology of animals and humans

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A. O. Mikheev

2017-12-01

Full Text Available Infectious diseases that are caused by numerous pathogenic microorganisms – bacteria, viruses, protozoa or fungi – can be transmitted from patients or carriers to healthy people or animals. A large group of infectious disease is caused by pathogens of animal infections – zoonoses. The issue of zoonoses is of great significance in human pathology and requires comprehensive study. This is of particular relevance to Ukraine, as the question of prevalence, level within the population and threats to human life and health from zoonoses, though highly important, has remained insufficiently studied. Information about many of these pathogens is absent in the existing scientific literature accessible in Ukraine – both veterinary and medical. This applies, in particular, to a causative agent of viral zoonoses the Borna disease virus or Bornavirus. For this purpose, an analysis of the literature concerning the role of the Bornavirus in the pathology of animals and humans was conducted. It is well known that a large number of pathogens of animal infections (zoonoses, including viral, pose a potential threat to human health. Among these potential threats is the Borna disease virus belonging to the family of Bornaviridae, order Mononegavirales. This order includes representatives of deadly human diseases like rabies (family Rhabdoviridae, Ebola virus (family Filoviridae and Nipah virus (family Paramyxoviridae. Borna virus disease affects mainly mammals, but can infect birds and even reptiles (Aspid bornavirus. It is established that Bornaviruses have a wide range of natural hosts (horses, sheeps, cats, bats and various birds, including domestic animals, which poses a potential threat to human health. This is evidenced by numerous, although contradictory, research into the role of the Borna disease virus in human pathologies such as schizophrenia, depression, prolonged fatigue syndrome, multiple sclerosis and others. Analysis of the literature clearly

Outbreaks of avian influenza A (H5N2), (H5N8), and (H5N1) among birds--United States, December 2014-January 2015.

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Jhung, Michael A; Nelson, Deborah I

2015-02-06

During December 15, 2014-January 16, 2015, the U.S. Department of Agriculture received 14 reports of birds infected with Asian-origin, highly pathogenic avian influenza A (HPAI) (H5N2), (H5N8), and (H5N1) viruses. These reports represent the first reported infections with these viruses in U.S. wild or domestic birds. Although these viruses are not known to have caused disease in humans, their appearance in North America might increase the likelihood of human infection in the United States. Human infection with other avian influenza viruses, such as HPAI (H5N1) and (H5N6) viruses and (H7N9) virus, has been associated with severe, sometimes fatal, disease, usually following contact with poultry.

Genetic and pathogenic characteristics of H1 avian and swine influenza A viruses.

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Kang, Hyun-Mi; Lee, Eun-Kyoung; Song, Byung-Min; Jeong, Jipseol; Kim, Hye-Ryoung; Choi, Eun-Jin; Shin, Yeun-Kyung; Lee, Hee-Soo; Lee, Youn-Jeong

2014-10-01

This study examined the potential for cross-species transmission of influenza viruses by comparing the genetic and pathogenic characteristics of H1 avian influenza viruses (AIVs) with different host origins in Korea. Antigenic and phylogenetic analyses of H1 AIVs circulating in Korea provided evidence of genetic similarity between viruses that infect domestic ducks and those that infect wild birds, although there was no relationship between avian and swine viruses. However, there were some relationships between swine and human viral genes. The replication and pathogenicity of the H1 viruses was assessed in chickens, domestic ducks and mice. Viral shedding in chickens was relatively high. Virus was recovered from both oropharyngeal and cloacal swabs up to 5-10 days post-inoculation. The titres of domestic duck viruses in chickens were much higher than those of wild-bird viruses. Both domestic duck and wild-bird viruses replicated poorly in domestic ducks. None of the swine viruses replicated in chickens or domestic ducks; however, six viruses showed relatively high titres in mice, regardless of host origin, and induced clinical signs such as ruffled fur, squatting and weight loss. Thus, although the phylogenetic and antigenic analyses showed no evidence of interspecies transmission between birds and swine, the results suggest that Korean H1 viruses have the potential to cause disease in mammals. Therefore, we should intensify continuous monitoring of avian H1 viruses in mammals and seek to prevent interspecies transmission. © 2014 The Authors.

Construction of an infectious cDNA clone of genotype 1 avian hepatitis E virus: characterization of its pathogenicity in broiler breeders and demonstration of its utility in studying the role of the hypervariable region in virus replication.

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Park, Soo-Jeong; Lee, Byung-Woo; Moon, Hyun-Woo; Sung, Haan Woo; Yoon, Byung-Il; Meng, Xiang-Jin; Kwon, Hyuk Moo

2015-05-01

A full-length infectious cDNA clone of the genotype 1 Korean avian hepatitis E virus (avian HEV) (pT11-aHEV-K) was constructed and its infectivity and pathogenicity were investigated in leghorn male hepatoma (LMH) chicken cells and broiler breeders. We demonstrated that capped RNA transcripts from the pT11-aHEV-K clone were translation competent when transfected into LMH cells and infectious when injected intrahepatically into the livers of chickens. Gross and microscopic pathological lesions underpinned the avian HEV infection and helped characterize its pathogenicity in broiler breeder chickens. The avian HEV genome contains a hypervariable region (HVR) in ORF1. To demonstrate the utility of the avian HEV infectious clone, several mutants with various deletions in and beyond the known HVR were derived from the pT11-aHEV-K clone. The HVR-deletion mutants were replication competent in LMH cells, although the deletion mutants extending beyond the known HVR were non-viable. By using the pT11-aHEV-K infectious clone as the backbone, an avian HEV luciferase reporter replicon and HVR-deletion mutant replicons were also generated. The luciferase assay results of the reporter replicon and its mutants support the data obtained from the infectious clone and its derived mutants. To further determine the effect of HVR deletion on virus replication, the capped RNA transcripts from the wild-type pT11-aHEV-K clone and its mutants were injected intrahepatically into chickens. The HVR-deletion mutants that were translation competent in LMH cells displayed in chickens an attenuation phenotype of avian HEV infectivity, suggesting that the avian HEV HVR is important in modulating the virus infectivity and pathogenicity. © 2015 The Authors.

Unique Infectious Strategy of H5N1 Avian Influenza Virus Is Governed by the Acid-Destabilized Property of Hemagglutinin.

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Daidoji, Tomo; Watanabe, Yohei; Arai, Yasuha; Kajikawa, Junichi; Hirose, Ryohei; Nakaya, Takaaki

Highly pathogenic avian influenza (HPAI) H5N1 virus emerged in 1997 as a zoonotic disease in Hong Kong. It has since spread to Asia and Europe and is a serious threat to both the poultry industry and human health. For effective surveillance and possible prevention/control of HPAI H5N1 viruses, it is necessary to understand the molecular mechanism underlying HPAI H5N1 pathogenesis. The hemagglutinin (HA) protein of influenza A viruses (IAVs) is one of the major determinants of host adaptation, transmissibility, and viral virulence. The main function of the HA protein is to facilitate viral entry and viral genome release within host cells before infection. To achieve viral infection, IAVs belonging to different subtypes or strains induce viral-cell membrane fusion at different endosomal pH levels after internalization through endocytosis. However, host-specific endosomal pH also affects induction of membrane fusion followed by infection. The HA protein of HPAI H5N1 has a higher pH threshold for membrane fusion than the HA protein of classical avian influenza viruses. Although this particular property of HA (which governs viral infection) is prone to deactivation in the avian intestine or in an ambient environment, it facilitates efficient infection of host cells, resulting in a broad host tropism, regardless of the pH in the host endosome. Accumulated knowledge, together with further research, about the HA-governed mechanism underlying HPAI H5N1 virulence (i.e., receptor tropism and pH-dependent viral-cell membrane fusion) will be helpful for developing effective surveillance strategies and for prevention/control of HPAI H5N1 infection.

Airborne Transmission of Highly Pathogenic Influenza Virus during Processing of Infected Poultry.

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Bertran, Kateri; Balzli, Charles; Kwon, Yong-Kuk; Tumpey, Terrence M; Clark, Andrew; Swayne, David E

2017-11-01

Exposure to infected poultry is a suspected cause of avian influenza (H5N1) virus infections in humans. We detected infectious droplets and aerosols during laboratory-simulated processing of asymptomatic chickens infected with human- (clades 1 and 2.2.1) and avian- (clades 1.1, 2.2, and 2.1) origin H5N1 viruses. We detected fewer airborne infectious particles in simulated processing of infected ducks. Influenza virus-naive chickens and ferrets exposed to the air space in which virus-infected chickens were processed became infected and died, suggesting that the slaughter of infected chickens is an efficient source of airborne virus that can infect birds and mammals. We did not detect consistent infections in ducks and ferrets exposed to the air space in which virus-infected ducks were processed. Our results support the hypothesis that airborne transmission of HPAI viruses can occur among poultry and from poultry to humans during home or live-poultry market slaughter of infected poultry.

Evaluating surveillance strategies for the early detection of low pathogenicity avian influenza infections.

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Comin, Arianna; Stegeman, Arjan; Marangon, Stefano; Klinkenberg, Don

2012-01-01

In recent years, the early detection of low pathogenicity avian influenza (LPAI) viruses in poultry has become increasingly important, given their potential to mutate into highly pathogenic viruses. However, evaluations of LPAI surveillance have mainly focused on prevalence and not on the ability to act as an early warning system. We used a simulation model based on data from Italian LPAI epidemics in turkeys to evaluate different surveillance strategies in terms of their performance as early warning systems. The strategies differed in terms of sample size, sampling frequency, diagnostic tests, and whether or not active surveillance (i.e., routine laboratory testing of farms) was performed, and were also tested under different epidemiological scenarios. We compared surveillance strategies by simulating within-farm outbreaks. The output measures were the proportion of infected farms that are detected and the farm reproduction number (R(h)). The first one provides an indication of the sensitivity of the surveillance system to detect within-farm infections, whereas R(h) reflects the effectiveness of outbreak detection (i.e., if detection occurs soon enough to bring an epidemic under control). Increasing the sampling frequency was the most effective means of improving the timeliness of detection (i.e., it occurs earlier), whereas increasing the sample size increased the likelihood of detection. Surveillance was only effective in preventing an epidemic if actions were taken within two days of sampling. The strategies were not affected by the quality of the diagnostic test, although performing both serological and virological assays increased the sensitivity of active surveillance. Early detection of LPAI outbreaks in turkeys can be achieved by increasing the sampling frequency for active surveillance, though very frequent sampling may not be sustainable in the long term. We suggest that, when no LPAI virus is circulating yet and there is a low risk of virus introduction

Evaluating surveillance strategies for the early detection of low pathogenicity avian influenza infections.

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Arianna Comin

Full Text Available In recent years, the early detection of low pathogenicity avian influenza (LPAI viruses in poultry has become increasingly important, given their potential to mutate into highly pathogenic viruses. However, evaluations of LPAI surveillance have mainly focused on prevalence and not on the ability to act as an early warning system. We used a simulation model based on data from Italian LPAI epidemics in turkeys to evaluate different surveillance strategies in terms of their performance as early warning systems. The strategies differed in terms of sample size, sampling frequency, diagnostic tests, and whether or not active surveillance (i.e., routine laboratory testing of farms was performed, and were also tested under different epidemiological scenarios. We compared surveillance strategies by simulating within-farm outbreaks. The output measures were the proportion of infected farms that are detected and the farm reproduction number (R(h. The first one provides an indication of the sensitivity of the surveillance system to detect within-farm infections, whereas R(h reflects the effectiveness of outbreak detection (i.e., if detection occurs soon enough to bring an epidemic under control. Increasing the sampling frequency was the most effective means of improving the timeliness of detection (i.e., it occurs earlier, whereas increasing the sample size increased the likelihood of detection. Surveillance was only effective in preventing an epidemic if actions were taken within two days of sampling. The strategies were not affected by the quality of the diagnostic test, although performing both serological and virological assays increased the sensitivity of active surveillance. Early detection of LPAI outbreaks in turkeys can be achieved by increasing the sampling frequency for active surveillance, though very frequent sampling may not be sustainable in the long term. We suggest that, when no LPAI virus is circulating yet and there is a low risk of virus

Mesenchymal stromal cell treatment prevents H9N2 avian influenza virus-induced acute lung injury in mice

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Yan Li

2016-10-01

Full Text Available Abstract Background The avian influenza virus (AIV can cross species barriers and expand its host range from birds to mammals, even humans. Avian influenza is characterized by pronounced activation of the proinflammatory cytokine cascade, which perpetuates the inflammatory response, leading to persistent systemic inflammatory response syndrome and pulmonary infection in animals and humans. There are currently no specific treatment strategies for avian influenza. Methods We hypothesized that mesenchymal stromal cells (MSCs would have beneficial effects in the treatment of H9N2 AIV-induced acute lung injury in mice. Six- to 8-week-old C57BL/6 mice were infected intranasally with 1 × 104 MID50 of A/HONG KONG/2108/2003 [H9N2 (HK] H9N2 virus to induce acute lung injury. After 30 min, syngeneic MSCs were delivered through the caudal vein. Three days after infection, we measured the survival rate, lung weight, arterial blood gas, and cytokines in both bronchoalveolar lavage fluid (BALF and serum, and assessed pathological changes to the lungs. Results MSC administration significantly palliated H9N2 AIV-induced pulmonary inflammation by reducing chemokines and proinflammatory cytokines levels, as well as reducing inflammatory cell recruit into the lungs. Thus, H9N2 AIV-induced lung injury was markedly alleviated in mice treated with MSCs. Lung histopathology and arterial blood gas analysis were improved in mice with H9N2 AIV-induced lung injury following MSC treatment. Conclusions MSC treatment significantly reduces H9N2 AIV-induced acute lung injury in mice and is associated with reduced pulmonary inflammation. These results indicate a potential role for MSC therapy in the treatment of clinical avian influenza.

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

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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.

Evidence-Based Advances in Avian Medicine.

Science.gov (United States)

Summa, Noémie M; Guzman, David Sanchez-Migallon

2017-09-01

This article presents relevant advances in avian medicine and surgery over the past 5 years. New information has been published to improve clinical diagnosis in avian diseases. This article also describes new pharmacokinetic studies. Advances in the understanding and treatment of common avian disorders are presented in this article, as well. Although important progress has been made over the past years, there is still much research that needs to be done regarding the etiology, pathophysiology, diagnosis, and treatment of avian diseases and evidence-based information is still sparse in the literature. Copyright © 2017 Elsevier Inc. All rights reserved.

The stability of human, bovine and avian tuberculin purified protein derivative (PPD).

Science.gov (United States)

Maes, Mailis; Giménez, José Francisco; D'Alessandro, Adriana; De Waard, Jacobus H

2011-11-15

Guidelines recommend storing tuberculin purified protein derivative (PPD) refrigerated. However, especially in developing countries, maintaining the product refrigerated under field conditions can be difficult, limiting its use. Here we determine the effect of prolonged exposure to high temperatures on the potency of human, bovine and avian tuberculin PPD. Human, bovine and avian tuberculin PPD were stored for several weeks exposed to temperatures ranging from 37º to 100ºC. The potency was evaluated in vivo, in sensitized or naturally infected animals. Most test situations didn't affect the biological activity of the tuberculin PPDs and only very long and extreme incubations (several days at 100 °C) compromised the potency. Tuberculin PPD is very stable and can be stored or transported for long periods without refrigeration. 

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.

Prevalence of Antibodies to H9N2 Avian Influenza Virus in Backyard Chickens around Maharlou Lake in Iran

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Mohammad Mehdi Hadipour*, Gholamhossein Habibi and Amir Vosoughi

2011-06-01

Full Text Available Backyard chickens play an important role in the epidemiology of H9N2 avian influenza virus infection. Close contact of backyard chickens with migratory birds, especially with aquatic birds, as well as neighboring poultry farms, may pose the risk of transmitting avian influenza virus, but little is known about the disease status of backyard poultry. A H9N2 avian influenza virus seroprevalence survey was carried out in 500 backyard chickens from villages around Maharlou lake in Iran, using the hemagglutination-inhibition (HI test. The studied backyard chickens had not been previously vaccinated and showed no clinical signs of disease. The overall HI titer and seroprevalence against H9N2 were 7.73 and 81.6%, respectively.

Development of a reverse transcription loop-mediated isothermal amplification method for the rapid detection of avian influenza virus subtype H7.

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Bao, Hongmei; Wang, Xiurong; Zhao, Yuhui; Sun, Xiaodong; Li, Yanbing; Xiong, Yongzhong; Chen, Hualan

2012-01-01

A rapid and sensitive reverse transcription loop-mediated isothermal amplification (RT-LAMP) method for the detection of the H7 avian influenza virus (H7 AIV) isotype was developed. The minimum detection limit of the RT-LAMP assay was 0.1-0.01 PFU per reaction for H7 AIV RNA, making this assay 100-fold more sensitive than the conventional RT-PCR method. This RT-LAMP assay also has the capacity to detect both high- and low-pathogenic H7 AIV strains. Using a pool of RNAs extracted from influenza viruses corresponding to all 15 HA subtypes (in addition to other avian pathogenic viruses), the RT-LAMP system was confirmed to amplify only H7 AIV RNA. Furthermore, specific pathogen free (SPF) chickens were infected artificially with H7 AIV, throat and cloacal swabs were collected, and viral shedding was examined using viral isolation, RT-PCR and RT-LAMP. Shedding was detected following viral isolation and RT-LAMP one day after infection, whereas viral detection using RT-PCR was effective only on day 3 post-infection. These results indicate that the RT-LAMP method could facilitate epidemiological surveillance and the rapid diagnosis of the avian influenza subtype H7. Copyright © 2011 Elsevier B.V. All rights reserved.

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

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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 ...

Markov Chain Estimation of Avian Seasonal Fecundity

Science.gov (United States)

To explore the consequences of modeling decisions on inference about avian seasonal fecundity we generalize previous Markov chain (MC) models of avian nest success to formulate two different MC models of avian seasonal fecundity that represent two different ways to model renestin...

Avian Influenza: Potential Impact on Sub-Saharan Military Populations with High Rates of Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome

National Research Council Canada - National Science Library

Feldman, Robert L; Nickell, Kent

2007-01-01

...)/acquired immunodeficiency syndrome. With the arrival of avian influenza in Africa, the potential exists that some of those soldiers might also become infected with H5N1, the virus responsible for the disease...

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

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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.

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.

Virus interference between H7N2 low pathogenic avian influenza virus and lentogenic Newcastle disease virus in experimental co-infections in chickens and turkeys.

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

2014-01-06

Low pathogenicity avian influenza virus (LPAIV) and lentogenic Newcastle disease virus (lNDV) are commonly reported causes of respiratory disease in poultry worldwide with similar clinical and pathobiological presentation. Co-infections do occur but are not easily detected, and the impact of co-infections on pathobiology is unknown. In this study chickens and turkeys were infected with a lNDV vaccine strain (LaSota) and a H7N2 LPAIV (A/turkey/VA/SEP-67/2002) simultaneously or sequentially three days apart. No clinical signs were observed in chickens co-infected with the lNDV and LPAIV or in chickens infected with the viruses individually. However, the pattern of virus shed was different with co-infected chickens, which excreted lower titers of lNDV and LPAIV at 2 and 3 days post inoculation (dpi) and higher titers at subsequent time points. All turkeys inoculated with the LPAIV, whether or not they were exposed to lNDV, presented mild clinical signs. Co-infection effects were more pronounced in turkeys than in chickens with reduction in the number of birds shedding virus and in virus titers, especially when LPAIV was followed by lNDV. In conclusion, co-infection of chickens or turkeys with lNDV and LPAIV affected the replication dynamics of these viruses but did not affect clinical signs. The effect on virus replication was different depending on the species and on the time of infection. These results suggest that infection with a heterologous virus may result in temporary competition for cell receptors or competent cells for replication, most likely interferon-mediated, which decreases with time.

Current situation on highly pathogenic avian influenza

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Avian influenza is one of the most important diseases affecting the poultry industry worldwide. Avian influenza viruses can cause a range of clinical disease in poultry. Viruses that cause severe disease and mortality are referred to as highly pathogenic avian influenza (HPAI) viruses. The Asian ...

Mosquito blood-meal analysis for avian malaria study in wild bird communities: laboratory verification and application to Culex sasai (Diptera: Culicidae) collected in Tokyo, Japan.

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Kim, Kyeong Soon; Tsuda, Yoshio; Sasaki, Toshinori; Kobayashi, Mutsuo; Hirota, Yoshikazu

2009-10-01

We conducted laboratory experiments to verify molecular techniques of avian malaria parasite detection distinguishing between an infected mosquito (oocysts on midgut wall) and infective mosquito (sporozoites in salivary glands) in parallel with blood-meal identification from individual blood-fed mosquitoes prior to application to field survey for avian malaria. Domestic fowl infected with Plasmodium gallinaceum was exposed to a vector and non-vector mosquito species, Aedes aegypti and Culex pipiens pallens, respectively, to compare the time course of polymerase chain reaction (PCR) detection for parasite between competent and refractory mosquitoes. DNA of the domestic fowl was detectable for at least 3 days after blood feeding. The PCR-based detection of P. gallinaceum from the abdomen and thorax of A. aegypti corresponded to the microscopic observation of oocysts and sporozoites. Therefore, this PCR-based method was considered useful as one of the criteria to assess developmental stages of Plasmodium spp. in mosquito species collected in the field. We applied the same PCR-based method to 21 blood-fed C. sasai mosquitoes collected in Rinshi-no-mori Park in urban Tokyo, Japan. Of 15 blood meals of C. sasai successfully identified, 86.7% were avian-derived, 13.3% were bovine-derived. Plasmodium DNA was amplified from the abdomen of three C. sasai specimens having an avian blood meal from the Great Tit (Parus major), Pale Thrush (Turdus pallidus), and Jungle Crow (Corvus macrorhynchos). This is the first field study on host-feeding habits of C. sasai in relation to the potential role as a vector for avian malaria parasites transmitted in the Japanese wild bird community.

Seroprevalence survey of H9N2 avian influenza virus in backyard chickens around the Caspian Sea in Iran

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MM Hadipour

2010-03-01

Full Text Available Since 1998, an epidemic of avian influenza occurred in the Iranian poultry industry. The identified agent presented low pathogenicity, and was subtyped as an H9N2 avian influenza virus. Backyard chickens can play an important role in the epidemiology of H9N2 avian influenza virus infection. Close contact of backyard chickens with migratory birds, especially with aquatic birds, as well as neighboring poultry farms, may pose the risk of transmitting avian influenza virus, but little is known about the disease status of backyard poultry. A H9N2 avian influenza virus seroprevalence survey was carried out in 700 backyard chickens from villages around the Caspian Sea, Northern Iran, using the hemagglutination-inhibition (HI test. The studied backyard chickens had not been previously vaccinated and showed no clinical signs of disease. The mean antibody titers found were 6.8, 7.5, 5.9, 7.2, 5.7, 6.4, 6.2 and the seroprevalence was 76.2%, 79.5%, 68.18%, 78.27%, 65%, 72.31% and 71.4% as found in seven villages. Overall HI titer and seroprevalence against H9N2 were 6.52 and 72.98%, respectively.

Dual function of the hemagglutinin H5 fused to chicken CD154 in a potential strategy of DIVA against avian influenza disease: preliminary study

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A.G. Pose

2015-09-01

Full Text Available In this study we demonstrated that the vaccine candidate against avian influenza virus H5N1 based on the hemagglutinin H5 (HA fused to the chicken CD154 (HACD can also be used for differentiating infected from vaccinated animals (DIVA. As the strategy of DIVA requires at least two proteins, we obtained a variant of the nucleoprotein (NP49-375 in E. coli. After its purification by IMAC, the competence of the proteins NP49-375 and HACD as coating antigens in indirect ELISA assays were tested by using the sera of chickens immunized with the proteins HA and HACD and the reference sera from several avian influenza subtypes. Together with these sera, the sera from different species of birds and the sera of chickens infected with other avian viral diseases were analyzed by competition ELISA assays coated with the proteins NP49-375 and HACD. The results showed that the segment CD154 in the chimeric protein HACD did not interfere with the recognition of the molecule HA by its specific antibodies. Also, we observed variable detection levels when the reference sera were analyzed in the ELISA plates coated with the protein NP49-375. Moreover, only the antibodies of the reference serum subtype H5 were detected in the ELISA plates coated with the protein HACD. The competition ELISA assays showed percentages of inhibition of 88-91% for the positives sera and less than 20% for the negative sera. We fixed the cut-off value of these assays at 25%. No antibody detection was observed in the sera from different species of birds or the sera of chickens infected with other avian viral diseases. This study supported the fact that the ELISA assays using the proteins NP49-375 and HACD could be valuable tools for avian influenza surveillance and as a strategy of DIVA for counteracting the highly pathogenic avian influenza virus H5N1 outbreaks.

Dual function of the hemagglutinin H5 fused to chicken CD154 in a potential strategy of DIVA against avian influenza disease: preliminary study.

Science.gov (United States)

Pose, A G; Rodríguez, E S; Méndez, A C; Gómez, J N; Redondo, A V; Rodríguez, E R; Ramos, E M G; Gutiérrez, A Á; Moltó, M P R; Roche, D G; Ugalde, Y S; López, A M

2015-01-01

In this study we demonstrated that the vaccine candidate against avian influenza virus H5N1 based on the hemagglutinin H5 (HA) fused to the chicken CD154 (HACD) can also be used for differentiating infected from vaccinated animals (DIVA). As the strategy of DIVA requires at least two proteins, we obtained a variant of the nucleoprotein (NP49-375) in E. coli. After its purification by IMAC, the competence of the proteins NP49-375 and HACD as coating antigens in indirect ELISA assays were tested by using the sera of chickens immunized with the proteins HA and HACD and the reference sera from several avian influenza subtypes. Together with these sera, the sera from different species of birds and the sera of chickens infected with other avian viral diseases were analyzed by competition ELISA assays coated with the proteins NP49-375 and HACD. The results showed that the segment CD154 in the chimeric protein HACD did not interfere with the recognition of the molecule HA by its specific antibodies. Also, we observed variable detection levels when the reference sera were analyzed in the ELISA plates coated with the protein NP49-375. Moreover, only the antibodies of the reference serum subtype H5 were detected in the ELISA plates coated with the protein HACD. The competition ELISA assays showed percentages of inhibition of 88-91% for the positives sera and less than 20% for the negative sera. We fixed the cut-off value of these assays at 25%. No antibody detection was observed in the sera from different species of birds or the sera of chickens infected with other avian viral diseases. This study supported the fact that the ELISA assays using the proteins NP49-375 and HACD could be valuable tools for avian influenza surveillance and as a strategy of DIVA for counteracting the highly pathogenic avian influenza virus H5N1 outbreaks.

Experimental Challenge of a Peridomestic Avian Species, European Starlings ( Sturnus vulgaris ), with Novel Influenza A H7N9 Virus from China.

Science.gov (United States)

Hall, Jeffrey S; Ip, Hon S; TeSlaa, Joshua L; Nashold, Sean W; Dusek, Robert J

2016-07-01

In 2013 a novel avian influenza H7N9 virus was isolated from several critically ill patients in China, and infection with this virus has since caused more than 200 human deaths. Live poultry markets are the likely locations of virus exposure to humans. Peridomestic avian species also may play important roles in the transmission and maintenance of H7N9 at live poultry markets. We experimentally challenged wild European Starlings ( Sturnus vulgaris ) with the novel H7N9 virus and measured virus excretion, clinical signs, and infectious dose. We found that European Starlings can be infected with this virus when inoculated with relatively high doses, and we predict that infected birds excrete sufficient amounts of virus to transmit to other birds, including domestic chickens. Infected European Starlings showed no clinical signs or mortality after infection with H7N9. This abundant peridomestic bird may be a source of the novel H7N9 virus in live poultry markets and may have roles in virus transmission to poultry and humans.

Experimental challenge of a peridomestic avian species, European Starlings (Sturnus vulgaris), with novel Influenza A H7N9 virus from China

Science.gov (United States)

Hall, Jeffrey S.; Ip, Hon S.; Teslaa, Joshua L.; Nashold, Sean W.; Dusek, Robert

2016-01-01

In 2013 a novel avian influenza H7N9 virus was isolated from several critically ill patients in China, and infection with this virus has since caused more than 200 human deaths. Live poultry markets are the likely locations of virus exposure to humans. Peridomestic avian species also may play important roles in the transmission and maintenance of H7N9 at live poultry markets. We experimentally challenged wild European Starlings (Sturnus vulgaris) with the novel H7N9 virus and measured virus excretion, clinical signs, and infectious dose. We found that European Starlings can be infected with this virus when inoculated with relatively high doses, and we predict that infected birds excrete sufficient amounts of virus to transmit to other birds, including domestic chickens. Infected European Starlings showed no clinical signs or mortality after infection with H7N9. This abundant peridomestic bird may be a source of the novel H7N9 virus in live poultry markets and may have roles in virus transmission to poultry and humans.

H9N2 avian influenza virus antibody titers in human population in fars province, Iran

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MM Hadipour

2010-09-01

Full Text Available Among the avian influenza A virus subtypes, H5N1 and H9N2 viruses have the potential to cause an influenza pandemic because they are widely prevalent in avian species in Asia and have demonstrated the ability to infect humans. This study was carried out to determined the seroprevalence of H9N2 avian influenza virus in different human populations in Fars province, which is situated in the south of Iran. Antibodies against H9N2 avian influenza virus were measured using hemagglutination-inhibition (HI test in sera from 300 individuals in five different population in Fars province, including poultry-farm workers, slaughter-house workers, veterinarians, patients with clinical signs of respiratory disease, and clinically normal individuals, who were not or rarely in contact with poultry. Mean antibody titers of 7.3, 6.8, 6.1, 4.5, and 2.9 and seroprevalences of 87%, 76.2%, 72.5%, 35.6%, and 23% were determined in those groups, respectively. Higher prevalences were detected in poultry-farm workers, slaughter-house workers, and veterinarians, possibly due to their close and frequent contact with poultry.

The avian-origin H3N2 canine influenza virus has limited replication in swine

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A genetically and antigenically distinct H3N2 canine influenza of avian-origin was detected in March of 2015 in Chicago, Illinois. A subsequent outbreak was reported with over 1,000 dogs in the Midwest affected. The potential for canine-to-swine transmission was unknown. Experimental infection in pi...

Avian Influenza surveillance: on the usability of FTA cards to solve biosafety and transport issues

NARCIS (Netherlands)

Kraus, R.H.; Hooft, van W.F.; Waldenstrom, J.; Latorre-Margalef, N.; Ydenberg, R.C.; Prins, H.H.T.

2011-01-01

Avian Influenza Viruses (AIVs) infect many mammals, including humans1. These AIVs are diverse in their natural hosts, harboring almost all possible viral subtypes2. Human pandemics of flu originally stem from AIVs3. Many fatal human cases during the H5N1 outbreaks in recent years were reported.

GADD45ß, an anti-tumor gene, inhibits avian leukosis virus subgroup J replication in chickens

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Avian leukosis virus subgroup J (ALV-J) is a retrovirus that induces neoplasia, hepatomegaly, immunosuppression and poor performance in chickens. The tumorigenic and pathogenic mechanisms of ALV-J remain a hot topic. To explore anti-tumor genes that confer genetic resistance to ALV-J infection in ch...

Induction of local and systemic immune reactions following infection of turkeys with avian Metapneumovirus (aMPV) subtypes A and B.

Science.gov (United States)

Liman, Martin; Rautenschlein, Silke

2007-02-15

Most of the studies regarding the immunopathogenesis of avian Metapneumovirus (aMPV) have been done with subtype C of aMPV. Not much is known about the immunopathogenesis of aMPV subtypes A and B in turkeys. Specifically, local immune reactions have not been investigated yet. We conducted two experiments in commercial turkeys. We investigated local and systemic humoral and cell mediated immune reactions following infection with an attenuated vaccine strain of aMPV subtype B (Experiment I) and virulent strains of aMPV subtypes A and B (Experiment II). Turkeys infected with virulent aMPV strains developed mild respiratory signs while birds inoculated with the attenuated aMPV did not show any clinical signs. Virus neutralizing antibodies were detected locally in tracheal washes and systemically in serum as soon as 5-7 days post aMPV infection (PI) independent of the strain used. Virus neutralizing antibody titres peaked at 7 days PI and then antibody levels declined. The peak of serum ELISA antibody production varied between infected groups and ranged from 14 and 28 days PI. All aMPV strains induced an increase in the percentage of CD4+ T cell populations in spleen and Harderian gland at days 7 or 14 PI. Furthermore, as shown in Experiment I, infection with the attenuated aMPV-B strain stimulated spleen leukocytes to release significantly higher levels of interferons (IFNs), interleukin-6 and nitric oxide in ex vivo culture in comparison to virus-free controls up to 7 days PI (P<0.05). As detected by quantitative real time RT-PCR in Experiment II, infection with virulent aMPV induced an increased IFNgamma expression in the Harderian gland in comparison to virus-free controls. IFNgamma expression in the spleen varied between aMPV strains and days PI. Overall, our study demonstrates that aMPV subtypes A and B infection induced humoral and cell mediated immune reactions comparable to subtype C infections. We observed only temporary stimulation of serum virus neutralizing

Population dynamics and rates of molecular evolution of a recently emerged paramyxovirus, avian metapneumovirus subtype C.

Science.gov (United States)

Padhi, Abinash; Poss, Mary

2009-02-01

We report the existence of two distinct sublineages of avian metapneumovirus (MPV) subtype C, a virus which has caused serious economic loss in commercial turkey farms in the United States. This subtype is closely related to human MPV, infects multiple avian species, and is globally distributed. The evolutionary rates of this virus are estimated to be 1.3 x 10(-3) to 7 x 10(-3) substitutions per site per year, and coalescent estimates place its emergence between 1991 and 1996. The four genes examined show a concordant demographic pattern which is characterized by a rapid increase in population size followed by stable population grown until the present.

Detection of Borna Disease Virus (BDV in Patients with First Episode of Schizophrenia

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Hasan Soltani

2016-12-01

Full Text Available Objective: Schizophrenia is a complex widespread neuropsychiatric disorder. This illness encompasses a complex debilitating mental disorder causing illusion, delusion, disturbed relationship, low motivation and decline of emotion. Viral infection of the brain including Borna Disease Virus (BDV may play a role in transient or permanent neurological and behavioral abnormalities. This role of Borna virus has not been resolved outright yet, and based on published papers investigation examining the role of this virus in schizophrenia is in progress worldwide.Method: In this study, Nested Reverse Transcription–Polymerase Chain Reaction (Nested RT-PCR was used for detection of BDV Ribonucleic Acid (RNA in Peripheral Blood Mononuclear Cells (PBMCs of a group of patients experiencing the first episode of schizophrenia. The results were compared with a normal group.Results: In our study, no BDV-positive was found in PBMCs of the case group. Out of 40 participants of control group one was positive for P24 gene of BDV. This result are similar to several published papers about this topic.Conclusion: An etiological relationship between Bornavirus and schizophrenia was not found in this study. More investigations are warranted to illustrate the probable relationship between bornavirus infection and schizophrenia.

Potential for Low-Pathogenic Avian H7 Influenza A Viruses To Replicate and Cause Disease in a Mammalian Model

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Zanin, Mark; Koçer, Zeynep A.; Poulson, Rebecca L.; Gabbard, Jon D.; Howerth, Elizabeth W.; Jones, Cheryl A.; Friedman, Kimberly; Seiler, Jon; Danner, Angela; Kercher, Lisa; McBride, Ryan; Paulson, James C.; Wentworth, David E.; Krauss, Scott; Tompkins, Stephen M.; Stallknecht, David E.

2016-01-01

ABSTRACT H7 subtype influenza A viruses are widely distributed and have been responsible for human infections and numerous outbreaks in poultry with significant impact. Despite this, the disease-causing potential of the precursor low-pathogenic (LP) H7 viruses from the wild bird reservoir has not been investigated. Our objective was to assess the disease-causing potential of 30 LP H7 viruses isolated from wild avian species in the United States and Canada using the DBA/2J mouse model. Without prior mammalian adaptation, the majority of viruses, 27 (90%), caused mortality in mice. Of these, 17 (56.7%) caused 100% mortality and 24 were of pathogenicity similar to that of A/Anhui/1/2013 (H7N9), which is highly pathogenic in mice. Viruses of duck origin were more pathogenic than those of shorebird origin, as 13 of 18 (72.2%) duck origin viruses caused 100% mortality while 4 of 12 (33.3%) shorebird origin viruses caused 100% mortality, despite there being no difference in mean lung viral titers between the groups. Replication beyond the respiratory tract was also evident, particularly in the heart and brain. Of the 16 viruses studied for fecal shedding, 11 were detected in fecal samples. These viruses exhibited a strong preference for avian-type α2,3-linked sialic acids; however, binding to mammalian-type α2,6-linked sialic acids was also detected. These findings indicate that LP avian H7 influenza A viruses are able to infect and cause disease in mammals without prior adaptation and therefore pose a potential public health risk. IMPORTANCE Low-pathogenic (LP) avian H7 influenza A viruses are widely distributed in the avian reservoir and are the precursors of numerous outbreaks of highly pathogenic avian influenza viruses in commercial poultry farms. However, unlike highly pathogenic H7 viruses, the disease-causing potential of LP H7 viruses from the wild bird reservoir has not been investigated. To address this, we studied 30 LP avian H7 viruses isolated from wild

77 FR 34783 - Highly Pathogenic Avian Influenza

Science.gov (United States)

2012-06-12

... [Docket No. APHIS-2006-0074] RIN 0579-AC36 Highly Pathogenic Avian Influenza AGENCY: Animal and Plant... regions where any subtype of highly pathogenic avian influenza (HPAI) is considered to exist. The interim... avian influenza (HPAI). On January 24, 2011, we published in the Federal Register (76 FR 4046-4056...

Detection and subtyping avian metapneumovirus from turkeys in Iran.

Science.gov (United States)

Mayahi, Mansour; Momtaz, Hassan; Jafari, Ramezan Ali; Zamani, Pejman

2017-01-01

Avian metapneumovirus (aMPV) causes diseases like rhinotracheitis in turkeys, swollen head syndrome in chickens and avian rhinotracheitis in other birds. Causing respiratory problems, aMPV adversely affects production and inflicts immense economic losses and mortalities, especially in turkey flocks. In recent years, several serological and molecular studies have been conducted on this virus, especially in poultry in Asia and Iran. The purpose of the present study was detecting and subtyping aMPV by reverse transcriptase polymerase chain reaction (RT-PCR) from non-vaccinated, commercial turkey flocks in Iran for the first time. Sixty three meat-type unvaccinated turkey flocks from several provinces of Iran were sampled in major turkey abattoirs. Samples were tested by RT-PCR for detecting and subtyping aMPV. The results showed that 26 samples from three flocks (4.10%) were positive for viral RNA and all of the viruses were found to be subtype B of aMPV. As a result, vaccination especially against subtype B of aMPV should be considered in turkey flocks in Iran to control aMPV infections.

The Relationship of Avian Influenza and Waterbirds in Creating Genetic Diversity and the Role of Waterbirds as Reservoir for Avian Influenza

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Dyah Ayu Hewajuli

2012-03-01

Full Text Available Outbreaks of Avian Influenza (AI has enormous implications for poultry and human health.These outbreaks are caused by influenza A virus that belongS to the family of Orthomyxoviridae. These viruses are RNA viruses, negative polarity, and the envelope has segmented genom. Generally, Avian Influenza is a disease which originally occurred in birds with complex ecology including reassortment and transmission among different species of birds and mammals. The gene of AI virus can be transmitted among human and avian species as shown by the virus reasortantment that caused pandemic human influenza in 1957 and 1968. Pandemi in 1957 and 1968 were different from previously human viruses because the substitution of several genes are derived from avian viruses. Wild waterfowls especially Anseriformes (duck, muscovy duck and geese and Charadriiformes (gulls, seabirds, wild birds are the natural reservoirs for influenza type A viruses and play important role on the ecology and propagation of the virus. From this reservoir, influenza type A virus usually can be transmitted to other birds, mammals (including human and caused outbreak of lethal diseases. Waterfowl that is infected with influenza A virus usually does not show any clinical symptoms. However, several reports stated that HPAI viruses can cause severe disease with neurogical disorders led to death in waterfowl. Migration of birds including waterfowls have active role in transmitting and spreading the disease. Movement of wild birds and inappropriate poultry trade transportation play a greater role as vector in spreading HPAI to humans. Ecological change of environment has also a great effect in spreading AI viruses. The spreading pattern of AI viruses is usually influenced by seasons, where the prevalence of AI was reported to be in the fall, winter and rainy seasons. Finally, the effective control strategies against the spreading of AI viruses is required. Programs of monitoring, surveilence and

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

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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.

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

Science.gov (United States)

Chaves, Aida J; Busquets, Núria; Valle, Rosa; Rivas, Raquel; Vergara-Alert, Júlia; Dolz, Roser; Ramis, Antonio; Darji, Ayub; Majó, Natàlia

2011-10-07

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.

Production of monoclonal antibodies for Avian Metapneumovirus (SHS-BR-121) isolated in Brazil

OpenAIRE

Coswig,LT; Stach-Machado,DR; Arns,CW

2007-01-01

Avian Metapneumovirus (aMPV), also called Turkey Rhinotracheitis Virus (TRTV), is an upper respiratory tract infection of turkeys, chickens and other avian species. Five monoclonal antibodies (MAbs) were created against the Brazilian isolate (SHS-BR-121) of aMPV, MAbs 1A5B8; 1C1C4; 2C2E9 and 2A4C3 of IgG1 and MAb 1C1F8 of IgG2a. Four Mabs (1A5B8; 1C1C4; 2C2E9 and 2A4C3) showed neutralizing activity and three (1A5B8; 1C1C4 and 2A4C3) inhibited cellular fusion in vitro. These MAbs were used to ...

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. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Silent spread of highly pathogenic Avian Influenza H5N1 virus amongst vaccinated commercial layers

NARCIS (Netherlands)

Poetri, O.N.; Boven, M.; Claassen, I.J.T.M.; Koch, G.; Wibawan, I.W.; Stegeman, A.; Broek, van den J.; Bouma, A.

2014-01-01

The aim of this study was to determine whether a single vaccination of commercial layer type chickens with an inactivated vaccine containing highly pathogenic avian influenza virus strain H5N1 A/chicken/Legok/2003, carried out on the farm, was sufficient to protect against infection with the

Seroprevalence of Antibodies to Avian Influenza A (H5) and A (H9) Viruses among Market Poultry Workers, Hanoi, Vietnam, 2001

OpenAIRE

Uyeki, Timothy M.; Nguyen, Doan C.; Rowe, Thomas; Lu, Xiuhua; Hu-Primmer, Jean; Huynh, Lien P.; Hang, Nguyen L. K.; Katz, Jacqueline M.

2012-01-01

BACKGROUND: The frequency of avian influenza A virus infections among poultry workers is not well understood. METHODS: A seroprevalence study of market poultry workers and persons without occupational poultry exposure was conducted during 2001 in Hanoi, Vietnam. Sera were tested for avian influenza H5 and H9 antibodies by microneutralization and Western blot assays. RESULTS: Seroprevalence of H5 and H9 antibodies was 4% and 3% in poultry workers and 1% and 3.5% in non-poultry workers, respect...

Selective Bottlenecks Shape Evolutionary Pathways Taken during Mammalian Adaptation of a 1918-like Avian Influenza Virus.

Science.gov (United States)

Moncla, Louise H; Zhong, Gongxun; Nelson, Chase W; Dinis, Jorge M; Mutschler, James; Hughes, Austin L; Watanabe, Tokiko; Kawaoka, Yoshihiro; Friedrich, Thomas C

2016-02-10

Avian influenza virus reassortants resembling the 1918 human pandemic virus can become transmissible among mammals by acquiring mutations in hemagglutinin (HA) and polymerase. Using the ferret model, we trace the evolutionary pathway by which an avian-like virus evolves the capacity for mammalian replication and airborne transmission. During initial infection, within-host HA diversity increased drastically. Then, airborne transmission fixed two polymerase mutations that do not confer a detectable replication advantage. In later transmissions, selection fixed advantageous HA1 variants. Transmission initially involved a "loose" bottleneck, which became strongly selective after additional HA mutations emerged. The stringency and evolutionary forces governing between-host bottlenecks may therefore change throughout host adaptation. Mutations occurred in multiple combinations in transmitted viruses, suggesting that mammalian transmissibility can evolve through multiple genetic pathways despite phenotypic constraints. Our data provide a glimpse into avian influenza virus adaptation in mammals, with broad implications for surveillance on potentially zoonotic viruses. Copyright © 2016 Elsevier Inc. All rights reserved.

Protective measures and human antibody response during an avian influenza H7N3 outbreak in poultry in British Columbia, Canada.

Science.gov (United States)

Skowronski, Danuta M; Li, Yan; Tweed, S Aleina; Tam, Theresa W S; Petric, Martin; David, Samara T; Marra, Fawziah; Bastien, Nathalie; Lee, Sandra W; Krajden, Mel; Brunham, Robert C

2007-01-02

In 2004 an outbreak of avian influenza of the H7N3 subtype occurred among poultry in British Columbia, Canada. We report compliance with recommended protective measures and associated human infections during this outbreak. We sought voluntary participation by anyone (cullers, farmers and their families) involved in efforts to control the poultry outbreak. Recruitment was by advertisements at the worker deployment site, in local media and through newsletters sent directly to farmers. Sera were tested for antibody to H7N3 by microneutralization assay. A subset of 16 sera (including convalescent sera from 2 unprotected workers with conjunctivitis from whom virus had been isolated) was further tested by Western blot and routine and modified hemagglutination inhibition assays. A total of 167 people (20% to 25% of all workers) participated between May 7 and July 26, 2004. Of these, 19 had experienced influenza-like illness and 21 had experienced red or watery eyes. There was no significant association between illness reports and exposure to infected birds. Among 65 people who entered barns with infected birds, 55 (85%) had received influenza vaccine, 48 (74%) had received oseltamivir, and 55 (85%), 54 (83%) and 36 (55%) reported always wearing gloves, mask or goggles, respectively. Antibody to the H7 subtype was not detected in any sera. During the BC outbreak, compliance with recommended protective measures, especially goggles, was incomplete. Multiple back-up precautions, including oseltamivir prophylaxis, may prevent human infections and should be readily accessible and consistently used by those involved in the control of future outbreaks of avian influenza in poultry. Localized human avian influenza infections may not result in serologic response despite confirmed viral detection and culture.

Increased pathogenicity and shedding in chickens of a wild bird-origin low pathogenicity avian influenza virus of the H7N3 subtype following multiple in vivo passages in quail and turkey.

Science.gov (United States)

Cilloni, Filippo; Toffan, Anna; Giannecchini, Simone; Clausi, Valeria; Azzi, Alberta; Capua, Ilaria; Terregino, Calogero

2010-03-01

In order to investigate viral adaptation mechanisms to poultry, we performed serial in vivo passages of a wild bird low pathogenicity avian influenza isolate of the H7N3 subtype (A/mallard/Italy/33/01) in three different domestic species (chicken, turkey, and Japanese quail). The virus under study was administered via natural routes at the dose of 10(6) egg infective dose50/ 0.1 ml to chickens, turkeys, and quails in order to investigate the clinical susceptibility and the shedding levels after infection. Multiple in vivo passages of the virus were performed by serially infecting groups of five naive birds of each species, with samples collected from a previously infected group. Quails and turkeys were susceptible to infection for 10 serial passages, whereas chickens were susceptible to two cycles of infection only. Infection of chicken with the quail- and turkey-adapted viruses showed an increased pathogenicity and/or shedding, causing more severe clinical signs and/or higher levels of viral excretion compared to the original strain. The data obtained herein suggest that infection of selected avian species may facilitate the adaptation of avian influenza viruses originating from the wild bird reservoir to chicken. This is the first time turkey has been shown to act as a species in which a virus from the wild reservoir can increase its replication activity in other domestic species.

Mixed species flock, nest height, and elevation partially explain avian haemoparasite prevalence in Colombia.

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Angie D González

Full Text Available The high avian biodiversity present in the Neotropical region offers a great opportunity to explore the ecology of host-parasite relationships. We present a survey of avian haemoparasites in a megadiverse country and explore how parasite prevalences are related to physical and ecological host characteristics. Using light microscopy, we documented the presence of haemoparasites in over 2000 individuals belonging to 246 species of wild birds, from nine localities and several ecosystems of Colombia. We analysed the prevalence of six avian haemoparasite taxa in relation to elevation and the following host traits: nest height, nest type, foraging strata, primary diet, sociality, migratory behaviour, and participation in mixed species flocks. Our analyses indicate significant associations between both mixed species flocks and nest height and Haemoproteus and Leucocytozoon prevalence. The prevalence of Leucocytozoon increased with elevation, whereas the prevalence of Trypanosoma and microfilariae decreased. Plasmodium and Haemoproteus prevalence did not vary significantly with elevation; in fact, both parasites were found up to 3300 m above sea level. The distribution of parasite prevalence across the phylogeny of bird species included in this study showed little host phylogenetic signal indicating that infection rates in this system are evolutionarily labile. Vector distribution as well as the biology of transmission and the maintenance of populations of avian haemoparasites deserve more detailed study in this system.

Unusually High Mortality in Waterfowl Caused by Highly Pathogenic Avian Influenza A(H5N1) in Bangladesh

DEFF Research Database (Denmark)

Haider, Najmul; Sturm-Ramirez, K.; Khan, S. U.

2017-01-01

a survey in three of these villages to identify suspected human influenza-like illness cases and collected nasopharyngeal and throat swabs. We tested all swabs by real-time RT-PCR, sequenced cultured viruses, and examined tissue samples by histopathology and immunohistochemistry to detect and characterize...... and immunohistochemistry staining of avian influenza viral antigens were recognized in the brain, pancreas and intestines of ducks and chickens. We identified ten human cases showing signs compatible with influenza-like illness; four were positive for influenza A/H3; however, none were positive for influenza A/H5......Mortality in ducks and geese caused by highly pathogenic avian influenza A(H5N1) infection had not been previously identified in Bangladesh. In June-July 2011, we investigated mortality in ducks, geese and chickens with suspected H5N1 infection in a north-eastern district of the country to identify...

Radiological and clinical course of pneumonia in patients with avian influenza H5N1

International Nuclear Information System (INIS)

Bay, Ali; Etlik, Omer; Oner, A. Faik; Unal, Ozkan; Arslan, Halil; Bora, Aydin; Davran, Ramazan; Yuca, Sevil Ari; Dogan, Murat

2007-01-01

Introduction: We evaluated chest X-ray and clinical findings of patients with lower respiratory tract infection due to influenza H5N1 and presented the radiological findings and clinical course of the infection. Materials and methods: Between December 2005 and February 2006, eight hospitalized patients (median age 10, 5-15 years) with avian-flu were evaluated in this study. All patients were evaluated with chest X-ray and four of them with CT scan. Post mortem pathological characterization were also available for three of the patients. Results: A rapidly progressive pneumonia with high mortality rate was observed especially for cases with late admission. The major radiologic abnormalities were extensive pneumonic infiltration with segmental and multifocal distribution, mostly located in lower zones of the lung. No pleural effusion and hilar lymphadenopathy was noted. Conclusion: Avian flu may be presented as rapidly progressive pneumonia. The chest radiography has an important role in diagnosis and should be obtained daily because of rapid change of the findings that may necessitate prompt action

Radiological and clinical course of pneumonia in patients with avian influenza H5N1

Energy Technology Data Exchange (ETDEWEB)

Bay, Ali [Yuzuncu Yil University, Faculty of Medicine, Department of Pediatrics, Van (Turkey)]. E-mail: bayalibay@yahoo.com; Etlik, Omer [Yuzuncu Yil University, Faculty of Medicine, Department of Radiology, Van (Turkey); Oner, A. Faik [Yuzuncu Yil University, Faculty of Medicine, Department of Pediatrics, Van (Turkey); Unal, Ozkan [Yuzuncu Yil University, Faculty of Medicine, Department of Radiology, Van (Turkey); Arslan, Halil [Yuzuncu Yil University, Faculty of Medicine, Department of Radiology, Van (Turkey); Bora, Aydin [Yuzuncu Yil University, Faculty of Medicine, Department of Radiology, Van (Turkey); Davran, Ramazan [Yuzuncu Yil University, Faculty of Medicine, Department of Radiology, Van (Turkey); Yuca, Sevil Ari [Yuzuncu Yil University, Faculty of Medicine, Department of Pediatrics, Van (Turkey); Dogan, Murat [Yuzuncu Yil University, Faculty of Medicine, Department of Pediatrics, Van (Turkey)

2007-02-15

Introduction: We evaluated chest X-ray and clinical findings of patients with lower respiratory tract infection due to influenza H5N1 and presented the radiological findings and clinical course of the infection. Materials and methods: Between December 2005 and February 2006, eight hospitalized patients (median age 10, 5-15 years) with avian-flu were evaluated in this study. All patients were evaluated with chest X-ray and four of them with CT scan. Post mortem pathological characterization were also available for three of the patients. Results: A rapidly progressive pneumonia with high mortality rate was observed especially for cases with late admission. The major radiologic abnormalities were extensive pneumonic infiltration with segmental and multifocal distribution, mostly located in lower zones of the lung. No pleural effusion and hilar lymphadenopathy was noted. Conclusion: Avian flu may be presented as rapidly progressive pneumonia. The chest radiography has an important role in diagnosis and should be obtained daily because of rapid change of the findings that may necessitate prompt action.

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

Directory of Open Access Journals (Sweden)

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

Experimental challenge and pathology of highly pathogenic avian influenza virus H5N1 in dunlin (Calidris alpina), an intercontinental migrant shorebird species

Science.gov (United States)

Hall, Jeffrey S.; Franson, J. Christian; Gill, Robert E.; Meteyer, Carol U.; TeSlaa, Joshua L.; Nashold, Sean W.; Dusek, Robert J.; Ip, Hon S.

2011-01-01

Background Shorebirds (Charadriiformes) are considered one of the primary reservoirs of avian influenza. Because these species are highly migratory, there is concern that infected shorebirds may be a mechanism by which highly pathogenic avian influenza virus (HPAIV) H5N1 could be introduced into North America from Asia. Large numbers of dunlin (Calidris alpina) migrate from wintering areas in central and eastern Asia, where HPAIV H5N1 is endemic, across the Bering Sea to breeding areas in Alaska. Low pathogenic avian influenza virus has been previously detected in dunlin, and thus, dunlin represent a potential risk to transport HPAIV to North America. To date no experimental challenge studies have been performed in shorebirds.

Avian Influenza Virus A (H5N1), Detected through Routine Surveillance, in Child, Bangladesh

Science.gov (United States)

Alamgir, A.S.M.; Sultana, Rebecca; Islam, M. Saiful; Rahman, Mustafizur; Fry, Alicia M.; Shu, Bo; Lindstrom, Stephen; Nahar, Kamrun; Goswami, Doli; Haider, M. Sabbir; Nahar, Sharifun; Butler, Ebonee; Hancock, Kathy; Donis, Ruben O.; Davis, Charles T.; Zaman, Rashid Uz; Luby, Stephen P.; Uyeki, Timothy M.; Rahman, Mahmudur

2009-01-01

We identified avian influenza virus A (H5N1) infection in a child in Bangladesh in 2008 by routine influenza surveillance. The virus was of the same clade and phylogenetic subgroup as that circulating among poultry during the period. This case illustrates the value of routine surveillance for detection of novel influenza virus. PMID:19751601

Carcass Management During Avian Influenza Outbreaks

Science.gov (United States)

This page on Avian Influenza (AI) describes carcass management during Avian Flu outbreaks, including who oversees carcass management, how they're managed, environmental concerns from carcass management, and disinfection. The page also describes what AI is.

Avian-like breathing mechanics in maniraptoran dinosaurs

Science.gov (United States)

Codd, Jonathan R; Manning, Phillip L; Norell, Mark A; Perry, Steven F

2007-01-01

In 1868 Thomas Huxley first proposed that dinosaurs were the direct ancestors of birds and subsequent analyses have identified a suite of ‘avian’ characteristics in theropod dinosaurs. Ossified uncinate processes are found in most species of extant birds and also occur in extinct non-avian maniraptoran dinosaurs. Their presence in these dinosaurs represents another morphological character linking them to Aves, and further supports the presence of an avian-like air-sac respiratory system in theropod dinosaurs, prior to the evolution of flight. Here we report a phylogenetic analysis of the presence of uncinate processes in Aves and non-avian maniraptoran dinosaurs indicating that these were homologous structures. Furthermore, recent work on Canada geese has demonstrated that uncinate processes are integral to the mechanics of avian ventilation, facilitating both inspiration and expiration. In extant birds, uncinate processes function to increase the mechanical advantage for movements of the ribs and sternum during respiration. Our study presents a mechanism whereby uncinate processes, in conjunction with lateral and ventral movements of the sternum and gastral basket, affected avian-like breathing mechanics in extinct non-avian maniraptoran dinosaurs. PMID:17986432

Highly pathogenic avian influenza A (H5N1) virus in wildlife: diagnostics, epidemiology and molecular characteristics

NARCIS (Netherlands)

Keawcharoen, J.

2010-01-01

Since 2003, highly pathogenic avian influenza virus subtype H5N1 outbreaks have been reported in Southeast Asia causing high mortality in poultry and have also been found to cross the species barrier infecting human and other mammalian species. Thailand is one of the countries severely affected by

Engineering development of avian influenza virus detection system in a patient's body

International Nuclear Information System (INIS)

Budi Santoso; Romadhon; Sukandar; Istofa

2010-01-01

The avian influenza virus detection equipment in a patient's body has been made. Currently, detection of avian influenza virus carried out by expensive laboratory equipment's, so only certain hospitals can perform this detection. This developing equipment is expected to be cheaper than existing equipment and the diagnosis can be known immediately. The sensing device is made using the principle of nuclear radiation detection. Radiation comes from a drunk labelled tamiflu (oseltamivir) which is drunk to the patient. Tamiflu is a drug to catch, H5N1 viruses in a patient's body. A labelled tamiflu is tamiflu which is labelled by I-131 radioisotopes. The presence of virus in the body is proportional to the amount of radiation captured by the detector. The equipment is composed of a Geiger-Mueller (GM) pancake detector type, a signal processor, a counter, and a data processor (computer). The GM detector converts the radiation that comes into electrical signals. Electrical signal is then converted into TTL level pulses by the signal processor. Pulse counting results are processed by data processor. The total count is proportional to the amount of virus captured by labelled tamiflu. The measurement threshold can be set by medical officer through software. At a certain threshold can be inferred identified patients infected with avian influenza virus. If the measurement below the threshold means that the patient is still within safe limits. This equipment is expected to create avian influenza virus detection system that cheaply and quickly so that more and more hospitals are using to detect the avian influenza virus. (author)

Descriptive results of a prospective cohort study of avian influenza in the Mekong River Delta of Viet Nam.

Science.gov (United States)

Nguyen, Long V; Stevenson, M; Schauer, B; Nguyen, D T; Tran, Q D; Tien, T N; Tran, P T T; Jones, G; Prattley, D; Morris, R

2014-12-01

A prospective cohort study of avian influenza infection in poultry flocks was carried out in the Mekong River Delta of Viet Nam between December 2008 and April 2010. Our objectives were to (i) estimate the prevalence and incidence of avian influenza virus infection and (ii) assess the efficacy of H5N1 vaccination programmes as indicated by the presence of H5 antibody in vaccinated and unvaccinated poultry. Real-time PCR and H5 multiplex assays were used to detect the antigen of avian influenza viruses from swab samples. The haemagglutination inhibition test was used to detect H5 antibody. A total of 17 968 swab and 14 878 blood samples were collected from 5476 birds over the study period. The overall incidence rate of influenza type A virus infection was 5 (95% CI 4-7) positive birds per 100 bird-months at risk. The overall incidence rate of H5 virus infection was 0.2 (95% CI 0.1-0.5) positive birds per 100 bird-months at risk. Fifty (95% CI 48-52) birds per 100 tested birds were H5 HI positive in the unvaccinated group compared with 71 (95% CI 69-73) birds per 100 in the vaccinated group. Influenza type A and H5 viruses were circulating in village poultry throughout the study period with no recorded signs of clinical disease. This implies that interventions need to be carried out continuously throughout the year rather than only focusing on the established high-risk periods. Broiler ducks had an incidence rate of influenza H5 virus infection approximately four times greater than that of layer ducks and in-contact species. We conclude that broiler ducks are likely to be the main entry route for H5 virus into poultry flocks in the MRD. Control efforts would benefit from understanding why there is a difference between villages in H5 incidence and developing strategies to provide greater protection to broiler ducks. © 2013 Blackwell Verlag GmbH.

Avian malaria Plasmodium relictum in native Hawaiian forest birds: epizootiology and demographic impacts on ‵apapane Himatione sanguinea

Science.gov (United States)

Atkinson, Carter T.; Samuel, Michael D.

2010-01-01

The role of introduced avian malaria Plasmodium relictum in the decline and extinction of native Hawaiian forest birds has become a classic example of the potential effect of invasive diseases on biological diversity of naïve populations. However, empirical evidence describing the impact of avian malaria on fitness of Hawai‵i's endemic forest birds is limited, making it difficult to determine the importance of disease among the suite of potential limiting factors affecting the distribution and abundance of this threatened avifauna. We combined epidemiological force-of-infection with multistate capture––recapture models to evaluate a 7-year longitudinal study of avian malaria in ‵apapane, a relatively common native honeycreeper within mid-elevation Hawaiian forests. We found that malaria transmission was seasonal in this mid-elevation forest; transmission peaked during fall and during some years produced epizootic mortality events. Estimated annual mortality of hatch-year birds typically exceeded 50% and mortality of adults exceeded 25% during epizootics. The substantial impact of avian malaria on this relatively common native species demonstrates the key role this disease has played in the decline and extinction of Hawaiian forest birds.

Human and avian influenza viruses target different cells in the lower respiratory tract of humans and other mammals

NARCIS (Netherlands)

D.A.J. van Riel (Debby); V.J. Munster (Vincent); E. de Wit (Emmie); G.F. Rimmelzwaan (Guus); R.A.M. Fouchier (Ron); A.D.M.E. Osterhaus (Albert); T. Kuiken (Thijs)

2007-01-01

textabstractViral attachment to the host cell is critical for tissue and species specificity of virus infections. Recently, pattern of viral attachment (PVA) in human respiratory tract was determined for highly pathogenic avian influenza virus of subtype H5N1. However, PVA of human influenza viruses

Multi-state analysis of the impacts of avian pox on a population of Serins (Serinus serinus): The importance of estimating recapture rates

Science.gov (United States)

Senar, J.C.; Conroy, M.J.

2004-01-01

Disease is one of the evolutionary forces shaping populations. Recent studies have shown that epidemics like avian pox, malaria, or mycoplasmosis have affected passerine population dynamics, being responsible for the decline of some populations or disproportionately killing males and larger individuals and thus selecting for specific morphotypes. However, few studies have estimated the effects of an epidemic by following individual birds using the capture-recapture approach. Because avian pox can be diagnosed by direct examination of the birds, we are here able to analyze, using multistate models, the development and consequences of an avian pox epidemic affecting in 1996, a population of Serins (Serinus serinus) in northeastern Spain. The epidemics lasted from June to the end of November of 1996, with a maximum apparent prevalence rate > 30% in October. However, recapture rate of sick birds was very high (0.81, range 0.37-0.93) compared to that of healthy birds (0.21, range 0.020-32), which highly inflated apparent prevalence rate. This was additionally supported by the low predicted transition from the state of being uninfected to the state of being infected (0.03, SE 0.03). Once infected, Serin avian pox was very virulent with (15-day) survival rate of infected birds being of only 0.46 (SE 0.17) compared to that of healthy ones (0.87, SE 0.03). Probability of recovery from disease, provided that the bird survived the first two weeks, however, was very high (0.65, SE 0.25). The use of these estimates together with a simple model, allowed us to predict an asymptotic increase to prevalence of about 4% by the end of the outbreak period, followed by a sharp decline, with the only remaining infestations being infected birds that had not yet recovered. This is in contrast to the apparent prevalence of pox and stresses the need to estimate recapture rates when estimating population dynamics parameters. ?? 2004 Museu de Cie??ncies Naturals.

Inactivated H9N2 avian influenza virus vaccine with gel-primed and mineral oil-boosted regimen could produce improved immune response in broiler breeders.

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Lee, D-H; Kwon, J-S; Lee, H-J; Lee, Y-N; Hur, W; Hong, Y-H; Lee, J-B; Park, S-Y; Choi, I-S; Song, C-S

2011-05-01

The frequent economic losses incurred with H9N2 low pathogenic avian influenza viruses (LPAI) infection have raised serious concerns for the poultry industry. A 1-dose regimen with inactivated H9N2 LPAI vaccine could not prevent vaccinated poultry from becoming infected and from shedding wild viruses. A study was conducted to determine whether a 2-dose regimen of inactivated H9N2 LPAI vaccine could enhance the immunologic response in chickens. Such gel-primed and mineral oil-boosted regimen has produced encouraging results associated with improved immune responses to an H9N2 LPAI. This strategy could be cost effective and helpful for preventing avian influenza virus in the poultry industry.

Experimental challenge and pathology of highly pathogenic avian influenza virus H5N1 in dunlin (Calidris alpina), an intercontinental migrant shorebird species.

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Hall, Jeffrey S; Franson, J Christian; Gill, Robert E; Meteyer, Carol U; TeSlaa, Joshua L; Nashold, Sean; Dusek, Robert J; Ip, Hon S

2011-09-01

Shorebirds (Charadriiformes) are considered one of the primary reservoirs of avian influenza. Because these species are highly migratory, there is concern that infected shorebirds may be a mechanism by which highly pathogenic avian influenza virus (HPAIV) H5N1 could be introduced into North America from Asia. Large numbers of dunlin (Calidris alpina) migrate from wintering areas in central and eastern Asia, where HPAIV H5N1 is endemic, across the Bering Sea to breeding areas in Alaska. Low pathogenic avian influenza virus has been previously detected in dunlin, and thus, dunlin represent a potential risk to transport HPAIV to North America. To date no experimental challenge studies have been performed in shorebirds. Wild dunlin were inoculated intranasally and intrachoanally various doses of HPAIV H5N1. The birds were monitored daily for virus excretion, disease signs, morbidity, and mortality. The infectious dose of HPAIV H5N1 in dunlin was determined to be 10(1.7) EID(50)/100 μl and that the lethal dose was 10(1.83) EID(50)/100 μl. Clinical signs were consistent with neurotropic disease, and histochemical analyses revealed that infection was systemic with viral antigen and RNA most consistently found in brain tissues. Infected birds excreted relatively large amounts of virus orally (10(4) EID(50)) and smaller amounts cloacally. Dunlin are highly susceptible to infection with HPAIV H5N1. They become infected after exposure to relatively small doses of the virus and if they become infected, they are most likely to suffer mortality within 3-5 days. These results have important implications regarding the risks of transport and transmission of HPAIV H5N1 to North America by this species and raises questions for further investigation. Published 2011. This article is a US Government work and is in the public domain in the USA.

Genomic and Phylogenetic Characterization of Novel, Recombinant H5N2 Avian Influenza Virus Strains Isolated from Vaccinated Chickens with Clinical Symptoms in China

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Huaiying Xu

2015-02-01

Full Text Available Infection of poultry with diverse lineages of H5N2 avian influenza viruses has been documented for over three decades in different parts of the world, with limited outbreaks caused by this highly pathogenic avian influenza virus. In the present study, three avian H5N2 influenza viruses, A/chicken/Shijiazhuang/1209/2013, A/chicken/Chiping/0321/2014, and A/chicken/Laiwu/0313/2014, were isolated from chickens with clinical symptoms of avian influenza. Complete genomic and phylogenetic analyses demonstrated that all three isolates are novel recombinant viruses with hemagglutinin (HA and matrix (M genes derived from H5N1, and remaining genes derived from H9N2-like viruses. The HA cleavage motif in all three strains (PQIEGRRRKR/GL is characteristic of a highly pathogenic avian influenza virus strain. These results indicate the occurrence of H5N2 recombination and highlight the importance of continued surveillance of the H5N2 subtype virus and reformulation of vaccine strains.

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

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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

Transcriptional profiling avian beta-defensins in chicken oviduct epithelial cells before and after infection with Salmonella enterica serovar Enteritidis

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Bailey R Hartford

2009-07-01

Full Text Available Abstract Background Salmonella enterica serovar Enteritidis (SE colonizes the ovary and oviduct of chickens without causing overt clinical signs which can lead to SE-contamination of the content and membrane of shell-eggs as well as hatchery eggs. The organism utilizes the Salmonella Pathogenicity Island-2 encoded type III secretion system (T3SS-2 to promote persistence in the oviduct of laying hens. In this study, reverse transcriptase-polymerase chain reaction (RT-PCR was carried out to determine the expression profiles of 14 known avian beta defensins (AvBDs in primary chicken oviduct epithelial cells (COEC before and after infections with a wild type SE strain and T3SS mutant SE strains carrying an inactivated sipA or pipB gene. Results Based on the expression levels in uninfected COEC, AvBDs can be loosely grouped into three categories with AvBD4-5 and AvBD9-12 being constitutively expressed at high levels; AvBD1, AvBD3, and AvBD13-14 at moderate levels; and AvBD2 and AvBD6-8 at minimal levels. Infection with the wild type SE strain temporarily repressed certain highly expressed AvBDs and induced the expression of minimally expressed AvBDs. The pipB mutant, compared to the wild type strain, had reduced suppressive effect on the expression of highly expressed AvBDs. Moreover, the pipB mutant elicited significantly higher levels of the minimally expressed AvBDs than the wild type SE or the sipA mutant did. Conclusion Chicken oviduct epithelial cells express most of the known AvBD genes in response to SE infection. PipB, a T3SS-2 effector protein, plays a role in dampening the β-defensin arm of innate immunity during SE invasion of chicken oviduct epithelium.

Transcriptional profiling avian beta-defensins in chicken oviduct epithelial cells before and after infection with Salmonella enterica serovar Enteritidis.

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Ebers, Katie L; Zhang, C Yan; Zhang, M Zhenyu; Bailey, R Hartford; Zhang, Shuping

2009-07-30

Salmonella enterica serovar Enteritidis (SE) colonizes the ovary and oviduct of chickens without causing overt clinical signs which can lead to SE-contamination of the content and membrane of shell-eggs as well as hatchery eggs. The organism utilizes the Salmonella Pathogenicity Island-2 encoded type III secretion system (T3SS-2) to promote persistence in the oviduct of laying hens. In this study, reverse transcriptase-polymerase chain reaction (RT-PCR) was carried out to determine the expression profiles of 14 known avian beta defensins (AvBDs) in primary chicken oviduct epithelial cells (COEC) before and after infections with a wild type SE strain and T3SS mutant SE strains carrying an inactivated sipA or pipB gene. Based on the expression levels in uninfected COEC, AvBDs can be loosely grouped into three categories with AvBD4-5 and AvBD9-12 being constitutively expressed at high levels; AvBD1, AvBD3, and AvBD13-14 at moderate levels; and AvBD2 and AvBD6-8 at minimal levels. Infection with the wild type SE strain temporarily repressed certain highly expressed AvBDs and induced the expression of minimally expressed AvBDs. The pipB mutant, compared to the wild type strain, had reduced suppressive effect on the expression of highly expressed AvBDs. Moreover, the pipB mutant elicited significantly higher levels of the minimally expressed AvBDs than the wild type SE or the sipA mutant did. Chicken oviduct epithelial cells express most of the known AvBD genes in response to SE infection. PipB, a T3SS-2 effector protein, plays a role in dampening the beta-defensin arm of innate immunity during SE invasion of chicken oviduct epithelium.

Population Dynamics and Rates of Molecular Evolution of a Recently Emerged Paramyxovirus, Avian Metapneumovirus Subtype C▿ †

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Padhi, Abinash; Poss, Mary

2009-01-01

We report the existence of two distinct sublineages of avian metapneumovirus (MPV) subtype C, a virus which has caused serious economic loss in commercial turkey farms in the United States. This subtype is closely related to human MPV, infects multiple avian species, and is globally distributed. The evolutionary rates of this virus are estimated to be 1.3 × 10−3 to 7 × 10−3 substitutions per site per year, and coalescent estimates place its emergence between 1991 and 1996. The four genes examined show a concordant demographic pattern which is characterized by a rapid increase in population size followed by stable population grown until the present. PMID:19052092

Respiratory transmission of an avian H3N8 influenza virus isolated from a harbour seal

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Karlsson, Erik A.; Ip, Hon S.; Hall, Jeffrey S.; Yoon, Sun W.; Johnson, Jordan; Beck, Melinda A.; Webby, Richard J.; Schultz-Cherry, Stacey

2014-01-01

The ongoing human H7N9 influenza infections highlight the threat of emerging avian influenza viruses. In 2011, an avian H3N8 influenza virus isolated from moribund New England harbour seals was shown to have naturally acquired mutations known to increase the transmissibility of highly pathogenic H5N1 influenza viruses. To elucidate the potential human health threat, here we evaluate a panel of avian H3N8 viruses and find that the harbour seal virus displays increased affinity for mammalian receptors, transmits via respiratory droplets in ferrets and replicates in human lung cells. Analysis of a panel of human sera for H3N8 neutralizing antibodies suggests that there is no population-wide immunity to these viruses. The prevalence of H3N8 viruses in birds and multiple mammalian species including recent isolations from pigs and evidence that it was a past human pandemic virus make the need for surveillance and risk analysis of these viruses of public health importance.

Outdoor ranging of poultry: a major risk factor for the introduction and development of high pathogenicity Avian Influenza

NARCIS (Netherlands)

Koch, G.; Elbers, A.R.W.

2006-01-01

High-Pathogenicity Avian Influenza (HPAI) is an extremely infectious viral disease of poultry. Public health concerns were raised when six persons died in Hong Kong in 1997 after exposure to HPAI-infected poultry. Its danger became imminent in the recent HPAI epidemic in South-East Asia when the

Adenovirus-Vectored Vaccine as a Rapid-Response Tool Against Avian Influenza Pandemic

International Nuclear Information System (INIS)

Van Kampen, K. R.; Tang, D. C.

2007-01-01

Influenza viruses in nature undergo genetic mutation and reassortment. Three pandemics of avian influenza in man were recorded in the twentieth century. Highly pathogenic avian influenza (HPAI) viruses currently in circulation pose a threat for another world-wide pandemic, if they become transmissible from man to man. Manufacturing protective vaccines using current egg-based technology is often difficult due to the virulence of the virus and its adverse effects on the embryonating egg substrate. New technologies allow the creation of safe and protective pandemic influenza vaccines without the need for egg based substrates. These technologies allow new vaccines to be created in less than one month. Manufacturing is in tissue culture, not eggs. Vaccine can be administered to man non-invasively, without adjuvants, eliciting a rapid and protective immune response. Protective immunity against avian influenza (AI) virus was elicited in chickens by single-dose in ovo vaccination with a replication-competent adenovirus (RCA)-free human adenovirus serotype 5 (Ad5)-derived vector encoding an H5N9 avian influenza virus hemagglutinin. Vaccinated chickens were protected against both H5N1 and H5N2 HPAI virus challenges. Mass-administration of this bird flu vaccine can be streamlined with available robotic in ovo injectors. Vaccination using this vaccine could protect the the largest host reservoir (chickens) and greatly reduce the exposure of man to avian influenza. In addition, Ad5-vectored vaccines can be produced rapidly and the safety margin of a non-replicating vector is superior to that of a replicating counterpart. Furthermore, this mode of vaccination is compatible with epidemiological surveys of natural AI virus infections. In addition to mass immunization of poultry, both animals and humans have been effectively immunized by intranasal administration of Ad5-vectored influenza vaccines without any appreciable side effects, even in mice and human volunteers with

Novel Eurasian highly pathogenic avian influenza A H5 viruses in wild birds, Washington, USA, 2014.

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Ip, Hon S; Torchetti, Mia Kim; Crespo, Rocio; Kohrs, Paul; DeBruyn, Paul; Mansfield, Kristin G; Baszler, Timothy; Badcoe, Lyndon; Bodenstein, Barbara; Shearn-Bochsler, Valerie; Killian, Mary Lea; Pedersen, Janice C; Hines, Nichole; Gidlewski, Thomas; DeLiberto, Thomas; Sleeman, Jonathan M

2015-05-01

Novel Eurasian lineage avian influenza A(H5N8) virus has spread rapidly and globally since January 2014. In December 2014, H5N8 and reassortant H5N2 viruses were detected in wild birds in Washington, USA, and subsequently in backyard birds. When they infect commercial poultry, these highly pathogenic viruses pose substantial trade issues.

Species-specific escape of Plasmodium sporozoites from oocysts of avian, rodent, and human malarial parasites.

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Orfano, Alessandra S; Nacif-Pimenta, Rafael; Duarte, Ana P M; Villegas, Luis M; Rodrigues, Nilton B; Pinto, Luciana C; Campos, Keillen M M; Pinilla, Yudi T; Chaves, Bárbara; Barbosa Guerra, Maria G V; Monteiro, Wuelton M; Smith, Ryan C; Molina-Cruz, Alvaro; Lacerda, Marcus V G; Secundino, Nágila F C; Jacobs-Lorena, Marcelo; Barillas-Mury, Carolina; Pimenta, Paulo F P

2016-08-02

Malaria is transmitted when an infected mosquito delivers Plasmodium sporozoites into a vertebrate host. There are many species of Plasmodium and, in general, the infection is host-specific. For example, Plasmodium gallinaceum is an avian parasite, while Plasmodium berghei infects mice. These two parasites have been extensively used as experimental models of malaria transmission. Plasmodium falciparum and Plasmodium vivax are the most important agents of human malaria, a life-threatening disease of global importance. To complete their life cycle, Plasmodium parasites must traverse the mosquito midgut and form an oocyst that will divide continuously. Mature oocysts release thousands of sporozoites into the mosquito haemolymph that must reach the salivary gland to infect a new vertebrate host. The current understanding of the biology of oocyst formation and sporozoite release is mostly based on experimental infections with P. berghei, and the conclusions are generalized to other Plasmodium species that infect humans without further morphological analyses. Here, it is described the microanatomy of sporozoite escape from oocysts of four Plasmodium species: the two laboratory models, P. gallinaceum and P. berghei, and the two main species that cause malaria in humans, P. vivax and P. falciparum. It was found that sporozoites have species-specific mechanisms of escape from the oocyst. The two model species of Plasmodium had a common mechanism, in which the oocyst wall breaks down before sporozoites emerge. In contrast, P. vivax and P. falciparum sporozoites show a dynamic escape mechanism from the oocyst via polarized propulsion. This study demonstrated that Plasmodium species do not share a common mechanism of sporozoite escape, as previously thought, but show complex and species-specific mechanisms. In addition, the knowledge of this phenomenon in human Plasmodium can facilitate transmission-blocking studies and not those ones only based on the murine and avian models.

Current situation of H9N2 subtype avian influenza in China.

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Gu, Min; Xu, Lijun; Wang, Xiaoquan; Liu, Xiufan

2017-09-15

In China, H9N2 subtype avian influenza outbreak is firstly reported in Guangdong province in 1992. Subsequently, the disease spreads into vast majority regions nationwide and has currently become endemic there. Over vicennial genetic evolution, the viral pathogenicity and transmissibility have showed an increasing trend as year goes by, posing serious threat to poultry industry. In addition, H9N2 has demonstrated significance to public health as it could not only directly infect mankind, but also donate partial or even whole cassette of internal genes to generate novel human-lethal reassortants like H5N1, H7N9, H10N8 and H5N6 viruses. In this review, we mainly focused on the epidemiological dynamics, biological characteristics, molecular phylogeny and vaccine strategy of H9N2 subtype avian influenza virus in China to present an overview of the situation of H9N2 in China.

Avian models in teratology and developmental toxicology.

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Smith, Susan M; Flentke, George R; Garic, Ana

2012-01-01

The avian embryo is a long-standing model for developmental biology research. It also has proven utility for toxicology research both in ovo and in explant culture. Like mammals, avian embryos have an allantois and their developmental pathways are highly conserved with those of mammals, thus avian models have biomedical relevance. Fertile eggs are inexpensive and the embryo develops rapidly, allowing for high-throughput. The chick genome is sequenced and significant molecular resources are available for study, including the ability for genetic manipulation. The absence of a placenta permits the direct study of an agent's embryotoxic effects. Here, we present protocols for using avian embryos in toxicology research, including egg husbandry and hatch, toxicant delivery, and assessment of proliferation, apoptosis, and cardiac structure and function.

Shedding of a low pathogenic avian influenza virus in a common synanthropic mammal--the cottontail rabbit.

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J Jeffrey Root

Full Text Available BACKGROUND: Cottontails (Sylvilagus spp. are common mammals throughout much of the U.S. and are often found in peridomestic settings, potentially interacting with livestock and poultry operations. If these animals are susceptible to avian influenza virus (AIV infections and shed the virus in sufficient quantities they may pose a risk for movement of avian influenza viruses between wildlife and domestic animals in certain situations. METHODOLOGY/PRINCIPAL FINDINGS: To assess the viral shedding potential of AIV in cottontails, we nasally inoculated fourteen cottontails with a low pathogenic AIV (H4N6. All inoculated cottontails shed relatively large quantities of viral RNA both nasally (≤ 10(6.94 PCR EID50 equivalents/mL and orally (≤ 10(5.09 PCR EID50 equivalents/mL. However, oral shedding tended to decline more quickly than did nasal shedding. No animals showed any obvious signs of disease throughout the study. Evidence of a serological response was found in all infected rabbits at 22 days post infection in convalescent sera. CONCLUSIONS/SIGNIFICANCE: To our knowledge, cottontails have not been previously assessed for AIV shedding. However, it was obvious that they shed AIV RNA extensively via the nasal and oral routes. This is significant, as cottontails are widely distributed throughout the U.S. and elsewhere. These mammals are often found in highly peridomestic situations, such as farms, parks, and suburban neighborhoods, often becoming habituated to human activities. Thus, if infected these mammals could easily transport AIVs short distances.

Fowl plague virus replication in mammalian cell-avian erythrocyte heterokaryons: studies concerning the actinomycin D and ultra-violet lig sensitive phase in influenza virus replication

International Nuclear Information System (INIS)

Kelly, D.C.; Dimmock, N.J.

1974-01-01

The replication of fowl plague virus in BHK and L cells specifically blocked prior to infection with inhibitors of influenza virus replication (actinomycin D and ultraviolet light irradiation) has been studied by the introduction of a metabolically dormant avian erythrocyte nucleus. This permits the synthesis of just the influenza virus nucleoprotein in actinomycin D (but not ultraviolet light) blocked cells. The NP antigen is first detected in the avian erythrocyte nucleus and subsequently in the heterokaryon cytoplasm

Genetic data provide evidence for wind-mediated transmission of highly pathogenic avian influenza.

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Ypma, Rolf J F; Jonges, Marcel; Bataille, Arnaud; Stegeman, Arjan; Koch, Guus; van Boven, Michiel; Koopmans, Marion; van Ballegooijen, W Marijn; Wallinga, Jacco

2013-03-01

Outbreaks of highly pathogenic avian influenza in poultry can cause severe economic damage and represent a public health threat. Development of efficient containment measures requires an understanding of how these influenza viruses are transmitted between farms. However, the actual mechanisms of interfarm transmission are largely unknown. Dispersal of infectious material by wind has been suggested, but never demonstrated, as a possible cause of transmission between farms. Here we provide statistical evidence that the direction of spread of avian influenza A(H7N7) is correlated with the direction of wind at date of infection. Using detailed genetic and epidemiological data, we found the direction of spread by reconstructing the transmission tree for a large outbreak in the Netherlands in 2003. We conservatively estimate the contribution of a possible wind-mediated mechanism to the total amount of spread during this outbreak to be around 18%.

Avian malaria: a new lease of life for an old experimental model to study the evolutionary ecology of Plasmodium.

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