1
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Wolters WJ, Vernooij JCM, Spliethof TM, Wiegel J, Elbers ARW, Spierenburg MAH, Stegeman JA, Velkers FC. Comparison of the Clinical Manifestation of HPAI H5Nx in Different Poultry Types in the Netherlands, 2014-2022. Pathogens 2024; 13:280. [PMID: 38668235 PMCID: PMC11055007 DOI: 10.3390/pathogens13040280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 03/04/2024] [Accepted: 03/21/2024] [Indexed: 04/29/2024] Open
Abstract
This study describes clinical manifestations of highly pathogenic avian influenza (HPAI) H5N1, H5N8 and H5N6 outbreaks between 2014 and 2018 and 2020 and 2022 in the Netherlands for different poultry types and age groups. Adult duck (breeder) farms and juvenile chicken (broiler and laying pullet) farms were not diagnosed before 2020. Outbreaks in ducks decreased in 2020-2022 vs. 2014-2018, but increased for meat-type poultry. Neurological, locomotor and reproductive tract signs were often observed in ducks, whereas laying- and meat-type poultry more often showed mucosal membrane and skin signs, including cyanosis and hemorrhagic conjunctiva. Juveniles (chickens and ducks) showed neurological and locomotor signs more often than adults. Diarrhea occurred more often in adult chickens and juvenile ducks. Mortality increased exponentially within four days before notification in chickens and ducks, with a more fluctuating trend in ducks and meat-type poultry than in layers. For ducks, a mortality ratio (MR) > 3, compared to the average mortality of the previous week, was reached less often than in chickens. A lower percentage of laying flocks with MR > 3 was found for 2020-2022 vs. 2014-2018, but without significant differences in clinical signs. This study provides a basis for improvements in mortality- and clinical-sign-based early warning criteria, especially for juvenile chickens and ducks.
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Affiliation(s)
- Wendy J. Wolters
- Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, The Netherlands; (W.J.W.); (J.C.M.V.)
| | - J. C. M. Vernooij
- Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, The Netherlands; (W.J.W.); (J.C.M.V.)
| | - Thomas M. Spliethof
- Division of Pathology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CS Utrecht, The Netherlands;
| | | | - Armin R. W. Elbers
- Department of Epidemiology, Bioinformatics, Animal Studies and Vaccine Development, Wageningen Bioveterinary Research, 8200 AB Lelystad, The Netherlands;
| | | | - J. Arjan Stegeman
- Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, The Netherlands; (W.J.W.); (J.C.M.V.)
| | - Francisca C. Velkers
- Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, The Netherlands; (W.J.W.); (J.C.M.V.)
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2
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Dolinski AC, Homola JJ, Jankowski MD, Robinson JD, Owen JC. Differential gene expression reveals host factors for viral shedding variation in mallards ( Anas platyrhynchos) infected with low-pathogenic avian influenza virus. J Gen Virol 2022; 103:10.1099/jgv.0.001724. [PMID: 35353676 PMCID: PMC10519146 DOI: 10.1099/jgv.0.001724] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Intraspecific variation in pathogen shedding impacts disease transmission dynamics; therefore, understanding the host factors associated with individual variation in pathogen shedding is key to controlling and preventing outbreaks. In this study, ileum and bursa of Fabricius tissues of wild-bred mallards (Anas platyrhynchos) infected with low-pathogenic avian influenza (LPAIV) were evaluated at various post-infection time points to determine genetic host factors associated with intraspecific variation in viral shedding. By analysing transcriptome sequencing data (RNA-seq), we found that LPAIV-infected wild-bred mallards do not exhibit differential gene expression compared to uninfected birds, but that gene expression was associated with cloacal viral shedding quantity early in the infection. In both tissues, immune gene expression was higher in high/moderate shedding birds compared to low shedding birds, and significant positive relationships with viral shedding were observed. In the ileum, expression for host genes involved in viral cell entry was lower in low shedders compared to moderate shedders at 1 day post-infection (DPI), and expression for host genes promoting viral replication was higher in high shedders compared to low shedders at 2 DPI. Our findings indicate that viral shedding is a key factor for gene expression differences in LPAIV-infected wild-bred mallards, and the genes identified in this study could be important for understanding the molecular mechanisms driving intraspecific variation in pathogen shedding.
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Affiliation(s)
- Amanda C. Dolinski
- Department of Fisheries and Wildlife, Michigan State
University, East Lansing, MI
| | - Jared J. Homola
- Department of Fisheries and Wildlife, Michigan State
University, East Lansing, MI
| | - Mark D. Jankowski
- Department of Fisheries and Wildlife, Michigan State
University, East Lansing, MI
- U.S. Environmental Protection Agency, Region 10, Seattle,
WA 98101
| | - John D. Robinson
- Department of Fisheries and Wildlife, Michigan State
University, East Lansing, MI
| | - Jennifer C. Owen
- Department of Fisheries and Wildlife, Michigan State
University, East Lansing, MI
- Department of Large Animal Clinical Sciences, Michigan
State University, East Lansing, MI, USA
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3
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Falendysz EA, Calhoun DM, Smith CA, Sleeman JM. Outside the Box: Working With Wildlife in Biocontainment. ILAR J 2021; 61:72-85. [PMID: 34428796 DOI: 10.1093/ilar/ilab025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Accepted: 06/02/2021] [Indexed: 12/11/2022] Open
Abstract
Research with captive wildlife in Animal Biosafety Level 2 (ABSL2) and 3 (ABSL3) facilities is becoming increasingly necessary as emerging and re-emerging diseases involving wildlife have increasing impacts on human, animal, and environmental health. Utilizing wildlife species in a research facility often requires outside the box thinking with specialized knowledge, practices, facilities, and equipment. The USGS National Wildlife Health Center (NWHC) houses an ABSL3 facility dedicated to understanding wildlife diseases and developing tools to mitigate their impacts on animal and human health. This review presents considerations for utilizing captive wildlife for infectious disease studies, including, husbandry, animal welfare, veterinary care, and biosafety. Examples are drawn from primary literature review and collective 40-year experience of the NWHC. Working with wildlife in ABSL2 and ABSL3 facilities differs from laboratory animals in that typical laboratory housing systems, husbandry practices, and biosafety practices are not designed for work with wildlife. This requires thoughtful adaptation of standard equipment and practices, invention of customized solutions and development of appropriate enrichment plans using the natural history of the species and the microbiological characteristics of introduced and native pathogens. Ultimately, this task requires critical risk assessment, understanding of the physical and psychological needs of diverse species, creativity, innovation, and flexibility. Finally, continual reassessment and improvement are imperative in this constantly changing specialty area of infectious disease and environmental hazard research.
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Affiliation(s)
- Elizabeth A Falendysz
- US Geological Survey, National Wildlife Health Center in Madison, Madison, Wisconsin, USA
| | - Dana M Calhoun
- Department of EBIO, University of Colorado Boulder, Boulder, Colorado, USA
| | - Carrie A Smith
- US Geological Survey, National Wildlife Health Center in Madison, Madison, Wisconsin, USA
| | - Jonathan M Sleeman
- US Geological Survey, National Wildlife Health Center in Madison, Madison, Wisconsin, USA
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4
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Jerry C, Stallknecht DE, Leyson C, Berghaus R, Jordan B, Pantin-Jackwood M, França MS. Age-Associated Changes in Recombinant H5 Highly Pathogenic and Low Pathogenic Avian Influenza Hemagglutinin Tissue Binding in Domestic Poultry Species. Animals (Basel) 2021; 11:ani11082223. [PMID: 34438681 PMCID: PMC8388419 DOI: 10.3390/ani11082223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 07/11/2021] [Accepted: 07/18/2021] [Indexed: 11/16/2022] Open
Abstract
The 2014 outbreak of clade 2.3.4.4A highly pathogenic avian influenza (HPAI) led to the culling of millions of commercial chickens and turkeys and death of various wild bird species. In this outbreak, older chickens and turkeys were commonly infected, and succumbed to clinical disease compared to younger aged birds such chicken broilers. Some experimental studies using waterfowl species have shown age-related differences in susceptibility to clinical disease with HPAI viruses. Here, we evaluate differences in H5 Hemagglutinin (HA) tissue binding across age groups, using recombinant H5 HA (rHA) proteins generated using gene sequences from low pathogenic (A/mallard/MN/410/2000(H5N2 (LPAIV)) and a HPAIV (A/Northern pintail/Washington/40964/2014(H5N2)) influenza A virus (IAV). Respiratory and intestinal tracts from chickens, ducks (Mallard, Pekin, Muscovy) and turkeys of different age groups were used to detect rHA binding with protein histochemistry, which was quantified as the median area of binding (MAB) used for statistical analysis. There were species and tissue specific differences in the rHA binding among the age groups; however, turkeys had significant differences in the HPAIV rHA binding in the respiratory tract, with younger turkeys having higher levels of binding in the lung compared to the older group. In addition, in the intestinal tract, younger turkeys had higher levels of binding compared to the older birds. Using LPAIV, similar species and tissues, specific differences were seen among the age groups; however, only turkeys had overall significant differences in the respiratory tract MAB, with the older birds having higher levels of binding compared to the younger group. No age-related differences were seen in the overall intestinal tract rHA binding. Age-related differences in rHA binding of the LPAIV and HPAIV demonstrated in this study may partially, but not completely, explain differences in host susceptibility to infection observed during avian influenza outbreaks and in experimental infection studies.
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Affiliation(s)
- Carmen Jerry
- California Animal Health and Food Safety Laboratory System, University of California, Davis, 1550 N. Soderquist Road, Turlock, CA 95380, USA
- Correspondence:
| | - David E. Stallknecht
- Southeastern Cooperative Wildlife Disease Study, 589 D.W. Brooks Drive, Athens, GA 30602, USA;
| | - Christina Leyson
- Southeast Poultry Research Laboratory, U.S. National Poultry Research Center, Agricultural Research Service, U.S. Department of Agriculture, 934 College Station Road, Athens, GA 30602, USA; (C.L.); (M.P.-J.)
| | - Roy Berghaus
- Veterinary Medical Center, Department of Population Health, 2200 College Station Road, Athens, GA 30602, USA;
| | - Brian Jordan
- Poultry Diagnostic and Research Center, University of Georgia Athens, 953 College Station Road, Athens, GA 30602, USA; (B.J.); (M.S.F.)
| | - Mary Pantin-Jackwood
- Southeast Poultry Research Laboratory, U.S. National Poultry Research Center, Agricultural Research Service, U.S. Department of Agriculture, 934 College Station Road, Athens, GA 30602, USA; (C.L.); (M.P.-J.)
| | - Monique S. França
- Poultry Diagnostic and Research Center, University of Georgia Athens, 953 College Station Road, Athens, GA 30602, USA; (B.J.); (M.S.F.)
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5
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Gorsich EE, Webb CT, Merton AA, Hoeting JA, Miller RS, Farnsworth ML, Swafford SR, DeLiberto TJ, Pedersen K, Franklin AB, McLean RG, Wilson KR, Doherty PF. Continental-scale dynamics of avian influenza in U.S. waterfowl are driven by demography, migration, and temperature. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2021; 31:e2245. [PMID: 33098602 PMCID: PMC7988533 DOI: 10.1002/eap.2245] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 06/20/2020] [Accepted: 08/16/2020] [Indexed: 06/11/2023]
Abstract
Emerging diseases of wildlife origin are increasingly spilling over into humans and domestic animals. Surveillance and risk assessments for transmission between these populations are informed by a mechanistic understanding of the pathogens in wildlife reservoirs. For avian influenza viruses (AIV), much observational and experimental work in wildlife has been conducted at local scales, yet fully understanding their spread and distribution requires assessing the mechanisms acting at both local, (e.g., intrinsic epidemic dynamics), and continental scales, (e.g., long-distance migration). Here, we combined a large, continental-scale data set on low pathogenic, Type A AIV in the United States with a novel network-based application of bird banding/recovery data to investigate the migration-based drivers of AIV and their relative importance compared to well-characterized local drivers (e.g., demography, environmental persistence). We compared among regression models reflecting hypothesized ecological processes and evaluated their ability to predict AIV in space and time using within and out-of-sample validation. We found that predictors of AIV were associated with multiple mechanisms at local and continental scales. Hypotheses characterizing local epidemic dynamics were strongly supported, with age, the age-specific aggregation of migratory birds in an area and temperature being the best predictors of infection. Hypotheses defining larger, network-based features of the migration processes, such as clustering or between-cluster mixing explained less variation but were also supported. Therefore, our results support a role for local processes in driving the continental distribution of AIV.
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Affiliation(s)
- Erin E. Gorsich
- School of Life SciencesUniversity of WarwickCoventryCV4 7ALUnited Kingdom
- The Zeeman Institute: Systems Biology and Infectious Disease Epidemiology Research (SBIDER)University of WarwickCoventryCV4 7ALUnited Kingdom
- Department of BiologyColorado State UniversityFort CollinsColorado80521USA
- Graduate Degree Program in EcologyColorado State UniversityFort CollinsColorado80521USA
| | - Colleen T. Webb
- Department of BiologyColorado State UniversityFort CollinsColorado80521USA
- Graduate Degree Program in EcologyColorado State UniversityFort CollinsColorado80521USA
| | - Andrew A. Merton
- Department of StatisticsColorado State UniversityFort CollinsColorado80521USA
| | - Jennifer A. Hoeting
- Department of StatisticsColorado State UniversityFort CollinsColorado80521USA
| | - Ryan S. Miller
- Centers for Epidemiology and Animal HealthUSDA APHIS Veterinary ServicesFort CollinsColorado80526USA
| | - Matthew L. Farnsworth
- Centers for Epidemiology and Animal HealthUSDA APHIS Veterinary ServicesFort CollinsColorado80526USA
| | - Seth R. Swafford
- National Wildlife Disease ProgramUSDA APHIS Wildlife ServicesFort CollinsColorado80521USA
- National Wildlife Refuge SystemUS Fish and Wildlife ServiceYazoo CityMississippi39194USA
| | - Thomas J. DeLiberto
- National Wildlife Disease ProgramUSDA APHIS Wildlife ServicesFort CollinsColorado80521USA
| | - Kerri Pedersen
- National Wildlife Disease ProgramUSDA APHIS Wildlife ServicesFort CollinsColorado80521USA
- USDA APHIS Wildlife ServicesRaleighNorth Carolina27606USA
| | - Alan B. Franklin
- National Wildlife Research CenterUSDA APHIS Wildlife ServicesFort CollinsColorado80521USA
| | - Robert G. McLean
- National Wildlife Research CenterUSDA APHIS Wildlife ServicesFort CollinsColorado80521USA
| | - Kenneth R. Wilson
- Department of Fish, Wildlife, and Conservation BiologyColorado State UniversityFort CollinsColorado80521USA
| | - Paul F. Doherty
- Department of Fish, Wildlife, and Conservation BiologyColorado State UniversityFort CollinsColorado80521USA
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6
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Jang Y, Seo SH. Age-Dependent Lethality in Ducks Caused by Highly Pathogenic H5N6 Avian Influenza Virus. Viruses 2020; 12:v12060591. [PMID: 32485904 PMCID: PMC7354466 DOI: 10.3390/v12060591] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 05/16/2020] [Accepted: 05/26/2020] [Indexed: 01/02/2023] Open
Abstract
Ducks show notably higher resistance to highly pathogenic avian influenza viruses as compared to chickens. Here, we studied the age-dependent susceptibility in ducks to the infections caused by highly pathogenic avian influenza viruses. We intranasally infected ducks aged 1, 2, 4, and 8 weeks with highly pathogenic H5N6 avian influenza viruses isolated in South Korea in 2016. All the 1-and 2-week-old ducks died after infection, 20% of 3-week-old ducks died, and from the ducks aged 4 and 8 weeks, all of them survived. We performed microarray analysis and quantitative real-time PCR using total RNA isolated from the lungs of infected 2- and 4-week-old ducks to determine the mechanism underlying the age-dependent susceptibility to highly pathogenic avian influenza virus. Limited genes were found to be differentially expressed between the lungs of 2- and 4-week-old ducks. Cell damage-related genes, such as CIDEA and ND2, and the immune response-related gene NR4A3 were notably induced in the lungs of infected 2-week-old ducks compared to those in the lungs of infected 4-week-old ducks.
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Affiliation(s)
- Yunyueng Jang
- Laboratory of Influenza Research and College of Veterinary Medicine, Chungnam National University, Daejeon 34134, Korea;
- Institute of Influenza Virus, Chungnam National University, Daejeon 34134, Korea
| | - Sang Heui Seo
- Laboratory of Influenza Research and College of Veterinary Medicine, Chungnam National University, Daejeon 34134, Korea;
- Institute of Influenza Virus, Chungnam National University, Daejeon 34134, Korea
- Correspondence: ; Tel.: +82-42-821-7819; Fax: +82-42-821-6762
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7
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Nolting JM, Lauterbach SE, Slemons RD, Bowman AS. Identifying Gaps in Wild Waterfowl Influenza A Surveillance in Ohio, United States. Avian Dis 2020; 63:145-148. [PMID: 31131571 DOI: 10.1637/11852-042018-reg.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 09/14/2018] [Indexed: 11/05/2022]
Abstract
The Mississippi Flyway is of utmost importance in monitoring influenza A viral diversity in the natural reservoir, as it is used by approximately 40% of North American migratory waterfowl. In 2008, influenza A virus (IAV) surveillance was initiated in eight states within the flyway during annual southern migration, to gain better insight into the natural history of influenza A viruses in the natural reservoir. More than 45,000 samples have been collected and tested, resulting in hundreds of diverse influenza A viral isolates, but seasonal sampling may not be the best strategy to gain insight into the natural history of IAV. To investigate the progress of this sampling strategy toward understanding the ecology of IAV in wild waterfowl, data from mallard ducks (Anas platyrhynchos) sampled nearly year-round in Ohio were examined. Overall, 3,645 samples were collected from mallards in Ohio from 2008 to 2016, with IAV being recovered from 13.6% of all samples collected. However, when data from each month are examined individually, it becomes apparent that the aggregated summary may be providing a misleading view of IAV in Ohio mallards. For instance, in August the frequency of viral recovery is 29.8%, with isolates representing at least 47 hemagglutinin/ neuraminidase (HA/NA) combinations. In November, during the height of southern migration, IAV isolation drops to 6.2%, with only 25 HA/NA combinations being represented. Our biased sampling towards convenience and high IAV recovery has created gaps in the data set, which prohibit a full understanding of the IAV ecology in this waterfowl population.
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Affiliation(s)
- Jacqueline M Nolting
- Department of Veterinary Preventive Medicine, The Ohio State University, Columbus, Ohio 43210,
| | - Sarah E Lauterbach
- Department of Veterinary Preventive Medicine, The Ohio State University, Columbus, Ohio 43210
| | - Richard D Slemons
- Department of Veterinary Preventive Medicine, The Ohio State University, Columbus, Ohio 43210
| | - Andrew S Bowman
- Department of Veterinary Preventive Medicine, The Ohio State University, Columbus, Ohio 43210
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8
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Germeraad EA, Sanders P, Hagenaars TJ, Jong MCMD, Beerens N, Gonzales JL. Virus Shedding of Avian Influenza in Poultry: A Systematic Review and Meta-Analysis. Viruses 2019; 11:v11090812. [PMID: 31480744 PMCID: PMC6784017 DOI: 10.3390/v11090812] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 08/14/2019] [Accepted: 08/21/2019] [Indexed: 11/19/2022] Open
Abstract
Understanding virus shedding patterns of avian influenza virus (AIV) in poultry is important for understanding host-pathogen interactions and developing effective control strategies. Many AIV strains were studied in challenge experiments in poultry, but no study has combined data from those studies to identify general AIV shedding patterns. These systematic review and meta-analysis were performed to summarize qualitative and quantitative information on virus shedding levels and duration for different AIV strains in experimentally infected poultry species. Methods were designed based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Four electronic databases were used to collect literature. A total of 1155 abstract were screened, with 117 studies selected for the qualitative analysis and 71 studies for the meta-analysis. A large heterogeneity in experimental methods was observed and the quantitative analysis showed that experimental variables such as species, virus origin, age, inoculation route and dose, affect virus shedding (mean, peak and duration) for highly pathogenic AIV (HPAIV), low pathogenic AIV (LPAIV) or both. In conclusion, this study highlights the need to standardize experimental procedures, it provides a comprehensive summary of the shedding patterns of AIV strains by infected poultry and identifies the variables that influence the level and duration of AIV shedding.
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Affiliation(s)
- Evelien A Germeraad
- Department of Virology, Wageningen Bioveterinary Research (WBVR), P.O. Box 65, 8200 AB Lelystad, The Netherlands.
| | - Pim Sanders
- Department of Bacteriology and Epidemiology, WBVR, P.O. Box 65, 8200 AB Lelystad, The Netherlands
- Quantitative Veterinary Epidemiology, Wageningen UR, P.O. Box 338, 6700AH Wageningen, The Netherlands
| | - Thomas J Hagenaars
- Department of Bacteriology and Epidemiology, WBVR, P.O. Box 65, 8200 AB Lelystad, The Netherlands
| | - Mart C M de Jong
- Quantitative Veterinary Epidemiology, Wageningen UR, P.O. Box 338, 6700AH Wageningen, The Netherlands
| | - Nancy Beerens
- Department of Virology, Wageningen Bioveterinary Research (WBVR), P.O. Box 65, 8200 AB Lelystad, The Netherlands
| | - Jose L Gonzales
- Department of Bacteriology and Epidemiology, WBVR, P.O. Box 65, 8200 AB Lelystad, The Netherlands
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9
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Hird SM, Ganz H, Eisen JA, Boyce WM. The Cloacal Microbiome of Five Wild Duck Species Varies by Species and Influenza A Virus Infection Status. mSphere 2018; 3:e00382-18. [PMID: 30355662 PMCID: PMC6200988 DOI: 10.1128/msphere.00382-18] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 09/26/2018] [Indexed: 02/08/2023] Open
Abstract
Waterfowl, especially ducks of the genus Anas, are natural reservoir species for influenza A virus (IAV). Duck populations contain nearly all the known diversity of IAVs, and the birds are asymptomatic to infection. Previous work established that IAV infection status is correlated with changes in the cloacal microbiome in juvenile mallards. Here, we analyze five Anas species to determine whether these duck species have similar IAV+ and IAV- cloacal microbiomes, or if the relationships among a host, influenza virus, and the microbiome are species specific. We assessed taxonomic composition of the microbiome, alpha diversity, and beta diversity and found very few patterns related to microbiome and infection status across species, while detecting strong differences within species. A host species-specific signal was stronger in IAV- ducks than IAV+ ducks, and the effect size of host species on the microbiome was three times higher in IAV- birds than IAV+ birds. The mallards and the northern shovelers, the species with highest sample sizes but also with differing feeding ecology, showed especially contrasting patterns in microbiome composition, alpha diversity, and beta diversity. Our results indicate that the microbiome may have a unique relationship with influenza virus infection at the species level.IMPORTANCE Waterfowl are natural reservoir species for influenza A virus (IAV). Thus, they maintain high levels of pathogen diversity, are asymptomatic to the infection, and also contribute to the risk of a global influenza pandemic. An individual's microbiome is a critical part in how a vertebrate manages pathogens and illness. Here, we describe the cloacal microbiome of 300 wild ducks, from five species (four with previously undescribed microbiomes), including both IAV-negative and IAV-positive individuals. We demonstrate that there is not one consistent "flu-like" microbiome or response to flu across species. Individual duck species appear to have unique relationships between their microbiomes and IAV, and IAV-negative birds have a stronger tie to host species than the IAV-positive birds. In a broad context, understanding the role of the microbiome in IAV reservoir species may have future implications for avian disease management.
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Affiliation(s)
- Sarah M Hird
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Holly Ganz
- AnimalBiome, Oakland, California, USA
- Genome Center, University of California, Davis, Davis, California, USA
| | - Jonathan A Eisen
- Genome Center, University of California, Davis, Davis, California, USA
| | - Walter M Boyce
- Pathology, Microbiology and Immunology, University of California, Davis, Davis, California, USA
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10
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Heterosubtypic immunity increases infectious dose required to infect Mallard ducks with Influenza A virus. PLoS One 2018; 13:e0196394. [PMID: 29698449 PMCID: PMC5919434 DOI: 10.1371/journal.pone.0196394] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Accepted: 04/12/2018] [Indexed: 11/19/2022] Open
Abstract
Previous field and experimental studies have demonstrated that heterosubtypic immunity (HSI) is a potential driver of Influenza A virus (IAV) prevalence and subtype diversity in mallards. Prior infection with IAV can reduce viral shedding during subsequent reinfection with IAV that have genetically related hemagglutinins (HA). In this experiment, we evaluated the effect of HSI conferred by an H3N8 IAV infection against increasing challenge doses of closely (H4N6) and distantly (H6N2) related IAV subtypes in mallards. Two groups of thirty 1-month-old mallards each, were inoculated with 105.9 50% embryo infectious doses (EID50) of an H3N8 virus or a mock-inoculum. One month later, groups of five birds each were challenged with increasing doses of H4N6 or H6N2 virus; age-matched, single infection control ducks were included for all challenges. Results demonstrate that naïve birds were infected after inoculation with 103 and 104 EID50 doses of the H4N6 or H6N2 virus, but not with 102 EID50 doses of either IAV. In contrast, with birds previously infected with H3N8 IAV, only one duck challenged with 104 EID50 of H4N6 IAV was shedding viral RNA at 2 days post-inoculation, and with H6N2 IAV, only birds challenged with the 104 EID50 dose were positive to virus isolation. Viral shedding in ducks infected with H6N2 IAV was reduced on days 2 and 3 post-inoculation compared to control birds. To explain the differences in the dose necessary to produce infection among H3-primed ducks challenged with H4N6 or H6N2 IAV, we mapped the amino acid sequence changes between H3 and H4 or H6 HA on predicted three-dimensional structures. Most of the sequence differences occurred between H3 and H6 at antigenic sites A, B, and D of the HA1 region. These findings demonstrate that the infectious dose necessary to infect mallards with IAV can increase as a result of HSI and that this effect is most pronounced when the HA of the viruses are genetically related.
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11
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Abstract
Waterbirds are the main reservoir for low pathogenic avian influenza A viruses (LPAIV), from which occasional spillover to poultry occurs. When circulating among poultry, LPAIV may become highly pathogenic avian influenza A viruses (HPAIV). In recent years, the epidemiology of HPAIV viruses has changed drastically. HPAIV H5N1 are currently endemic among poultry in a number of countries. In addition, global spread of HPAIV H5Nx viruses has resulted in major outbreaks among wild birds and poultry worldwide. Using data collected during these outbreaks, the role of migratory birds as a vector became increasingly clear. Here we provide an overview of current data about various aspects of the changing role of wild birds in the epidemiology of avian influenza A viruses.
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12
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Bárbara A, Torrontegi O, Camacho MC, Barral M, Hernández JM, Höfle U. Avian Influenza Virus Surveillance in South-Central Spain Using Fecal Samples of Aquatic Birds Foraging at Landfills. Front Vet Sci 2017; 4:178. [PMID: 29124060 PMCID: PMC5662893 DOI: 10.3389/fvets.2017.00178] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 10/04/2017] [Indexed: 11/13/2022] Open
Abstract
Aquatic wild birds have been intensively studied to better understand their role in avian influenza virus (AIV) maintenance and spread. To date, AIV surveillance has primarily focused on natural aquatic environments where different bird species aggregate and viral survival is enhanced. However, artificial habitats such as landfills are attracting substantial numbers of wild birds, AIV reservoir species included. The use of landfills as a predictable food source has significantly influenced population size, migratory traits, and feeding behavior of white storks (Ciconia ciconia) and black-headed gulls (Chroicocephalus ridibundus) among others. Considering the proximity of landfills to urban settlements and frequently poultry-farms, targeted monitoring of AIV in bird species that forage at landfills but are known to also frequent urban and agricultural habitats could be a useful means for monitoring of AIV, especially during periods of bird aggregation. During the wintering season 2014-2015, the prevalence of AIV in five avian species at two landfills in South-Central Spain was explored by rRT-PCR and species related temporal variation in AIV prevalence determined. We collected and tested 1,186 fresh fecal samples from white storks (N = 689), cattle egrets (Bubulcus ibis, N = 116) and mixed flocks of gulls (N = 381) as well as cloacal and oral swabs from five birds found dead. Seven samples contained AIV, five from gulls and one each from a stork and a cattle egret. Overall, AIV prevalence was 0.60%. No significant temporal variation was observed in AIV prevalence. Prevalence differed significantly among the sampled taxonomic groups, being highest in gulls (1.31%). H16N3 subtype was detected from a cattle egret and H11N9 subtype from a white stork, whereas gulls harbored both subtypes in addition to H11N3 subtype. H16 subtype detection in a cattle egret evidences its host range may not be restricted to gulls. Our results indicate that wild birds foraging at landfills may carry different LPAIV subtypes.
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Affiliation(s)
- Andreia Bárbara
- SaBio Working Group, Instituto de Investigación en Recursos Cinegéticos IREC (CSIC-UCLM-JCCM), Ciudad Real, Spain
| | | | - Maria-Cruz Camacho
- SaBio Working Group, Instituto de Investigación en Recursos Cinegéticos IREC (CSIC-UCLM-JCCM), Ciudad Real, Spain
| | | | - Jose-Manuel Hernández
- Freelancer (Formerly affiliated with Instituto de Investigación en Recursos Cinegéticos IREC (CSIC-UCLM), Universidad de Castilla-La Mancha, Ciudad Real, Spain), Ciudad Real, Spain
| | - Ursula Höfle
- SaBio Working Group, Instituto de Investigación en Recursos Cinegéticos IREC (CSIC-UCLM-JCCM), Ciudad Real, Spain
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Latorre-Margalef N, Brown JD, Fojtik A, Poulson RL, Carter D, Franca M, Stallknecht DE. Competition between influenza A virus subtypes through heterosubtypic immunity modulates re-infection and antibody dynamics in the mallard duck. PLoS Pathog 2017. [PMID: 28640898 PMCID: PMC5481145 DOI: 10.1371/journal.ppat.1006419] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Our overall hypothesis is that host population immunity directed at multiple antigens will influence the prevalence, diversity and evolution of influenza A virus (IAV) in avian populations where the vast subtype diversity is maintained. To investigate how initial infection influences the outcome of later infections with homologous or heterologous IAV subtypes and how viruses interact through host immune responses, we carried out experimental infections in mallard ducks (Anas platyrhynchos). Mallards were pre-challenged with an H3N8 low-pathogenic IAV and were divided into six groups. At five weeks post H3N8 inoculation, each group was challenged with a different IAV subtype (H4N5, H10N7, H6N2, H12N5) or the same H3N8. Two additional pre-challenged groups were inoculated with the homologous H3N8 virus at weeks 11 and 15 after pre-challenge to evaluate the duration of protection. The results showed that mallards were still resistant to re-infection after 15 weeks. There was a significant reduction in shedding for all pre-challenged groups compared to controls and the outcome of the heterologous challenges varied according to hemagglutinin (HA) phylogenetic relatedness between the viruses used. There was a boost in the H3 antibody titer after re-infection with H4N5, which is consistent with original antigenic sin or antigenic seniority and suggest a putative strategy of virus evasion. These results imply competition between related subtypes that could regulate IAV subtype population dynamics in nature. Collectively, we provide new insights into within-host IAV complex interactions as drivers of IAV antigenic diversity that could allow the circulation of multiple subtypes in wild ducks.
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Affiliation(s)
- Neus Latorre-Margalef
- Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, Department of Population Health, The University of Georgia, Athens, Georgia, United States of America
- Department of Biology, Lund University, Lund, Sweden
- * E-mail:
| | - Justin D. Brown
- Pennsylvania Game Commission, Pennsylvania State University, Animal Diagnostic Laboratory, University Park, Pennsylvania, United States of America
| | - Alinde Fojtik
- Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, Department of Population Health, The University of Georgia, Athens, Georgia, United States of America
| | - Rebecca L. Poulson
- Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, Department of Population Health, The University of Georgia, Athens, Georgia, United States of America
| | - Deborah Carter
- Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, Department of Population Health, The University of Georgia, Athens, Georgia, United States of America
| | - Monique Franca
- Poultry Diagnostic and Research Center, College of Veterinary Medicine, Department of Population Health, The University of Georgia, Athens, Georgia, United States of America
| | - David E. Stallknecht
- Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, Department of Population Health, The University of Georgia, Athens, Georgia, United States of America
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Dannemiller NG, Webb CT, Wilson KR, Bentler KT, Mooers NL, Ellis JW, Root JJ, Franklin AB, Shriner SA. Impact of body condition on influenza A virus infection dynamics in mallards following a secondary exposure. PLoS One 2017; 12:e0175757. [PMID: 28423047 PMCID: PMC5396890 DOI: 10.1371/journal.pone.0175757] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 03/30/2017] [Indexed: 11/19/2022] Open
Abstract
Migratory waterfowl are often viewed as vehicles for the global spread of influenza A viruses (IAVs), with mallards (Anas platyrhynchos) implicated as particularly important reservoir hosts. The physical demands and energetic costs of migration have been shown to influence birds' body condition; poorer body condition may suppress immune function and affect the course of IAV infection. Our study evaluated the impact of body condition on immune function and viral shedding dynamics in mallards naturally exposed to an H9 IAV, and then secondarily exposed to an H4N6 IAV. Mallards were divided into three treatment groups of 10 birds per group, with each bird's body condition manipulated as a function of body weight by restricting food availability to achieve either a -10%, -20%, or control body weight class. We found that mallards exhibit moderate heterosubtypic immunity against an H4N6 IAV infection after an infection from an H9 IAV, and that body condition did not have an impact on shedding dynamics in response to a secondary exposure. Furthermore, body condition did not affect aspects of the innate and adaptive immune system, including the acute phase protein haptoglobin, heterophil/lymphocyte ratios, and antibody production. Contrary to recently proposed hypotheses and some experimental evidence, our data do not support relationships between body condition, infection and immunocompetence following a second exposure to IAV in mallards. Consequently, while annual migration may be a driver in the maintenance and spread of IAVs, the energetic demands of migration may not affect susceptibility in mallards.
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Affiliation(s)
- Nicholas G. Dannemiller
- Department of Fish, Wildlife, and Conservation Biology, Colorado State University, Fort Collins, Colorado, United States of America
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, National Wildlife Research Center, Fort Collins, Colorado, United States of America
- * E-mail:
| | - Colleen T. Webb
- Department of Biology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Kenneth R. Wilson
- Department of Fish, Wildlife, and Conservation Biology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Kevin T. Bentler
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, National Wildlife Research Center, Fort Collins, Colorado, United States of America
| | - Nicole L. Mooers
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, National Wildlife Research Center, Fort Collins, Colorado, United States of America
| | - Jeremy W. Ellis
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, National Wildlife Research Center, Fort Collins, Colorado, United States of America
| | - J. Jeffrey Root
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, National Wildlife Research Center, Fort Collins, Colorado, United States of America
| | - Alan B. Franklin
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, National Wildlife Research Center, Fort Collins, Colorado, United States of America
| | - Susan A. Shriner
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, National Wildlife Research Center, Fort Collins, Colorado, United States of America
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Ferreira HL, Vangeluwe D, Van Borm S, Poncin O, Dumont N, Ozhelvaci O, Munir M, van den Berg T, Lambrecht B. Differential Viral Fitness Between H1N1 and H3N8 Avian Influenza Viruses Isolated from Mallards (Anas platyrhynchos). Avian Dis 2016; 59:498-507. [PMID: 26629623 DOI: 10.1637/11074-033015-reg] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Homosubtypic and heterosubtypic immunity in mallards (Anas platyrhynchos) play an important role in the avian influenza virus (AIV) diversity. The mechanisms of AIV replication among wild birds and the role of immunity in AIV diversity have thus not been completely clarified. During the monitoring of AI circulation among wild waterfowl in 2007-2008, two viruses (H3N8 and H1N1) were isolated from ducks caught in a funnel trap located in La Hulpe wetland in Belgium. H3N8 viruses were revealed to be more prevalent in the mallard population than was H1N1, which might suggest a better adaptation to this species. In order to investigate this hypothesis, we characterized both isolated viruses biologically by experimental inoculation. Virus excretion and humoral response induced by both isolated viruses were evaluated in mallards after a first infection followed by a homo- or heterosubtypic reinfection under controlled experimental conditions. The H1N1 virus had a delayed peak of excretion of 4 days compared to the H3N8, but the virus shedding was more limited, earlier, and shorter after each reinfection. Moreover, the H3N8 virus could spread to all ducks after homo- or heterosubtypic reinfections and during a longer period. Although the humoral response induced by both viruses after infection and reinfection could be detected efficiently by competitive ELISA, only a minimal H1 antibody response and almost no H3-specific antibodies could be detected by the HI test. Our results suggest that the H3N8 isolate replicates better in mallards under experimental controlled conditions.
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Affiliation(s)
- Helena Lage Ferreira
- A FZEA-USP, Av. Duque de Caxias Norte, 225, Pirassununga - Sao Paulo 13635-900, Brazil
| | - Didier Vangeluwe
- B Royal Belgian Institute of Natural Sciences Belgian Ringing Centre, Vautier Street 29, 1000 Brussels, Belgium
| | - Steven Van Borm
- C CODA-CERVA-VAR, Groeselenberg 99, B-1180 Brussels, Belgium
| | - Olivier Poncin
- B Royal Belgian Institute of Natural Sciences Belgian Ringing Centre, Vautier Street 29, 1000 Brussels, Belgium
| | - Nathalie Dumont
- C CODA-CERVA-VAR, Groeselenberg 99, B-1180 Brussels, Belgium
| | - Orkun Ozhelvaci
- C CODA-CERVA-VAR, Groeselenberg 99, B-1180 Brussels, Belgium
| | - Muhammad Munir
- D The Pirbright Institute, Ash Road, Pirbright, Woking, GU24 0NF, United Kingdom
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How Does Sampling Methodology Influence Molecular Detection and Isolation Success in Influenza A Virus Field Studies? Appl Environ Microbiol 2015; 82:1147-1153. [PMID: 26655759 DOI: 10.1128/aem.03283-15] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 11/20/2015] [Indexed: 11/20/2022] Open
Abstract
Wild waterfowl are important reservoir hosts for influenza A virus (IAV) and a potential source of spillover infections in other hosts, including poultry and swine. The emergence of highly pathogenic avian influenza (HPAI) viruses, such as H5N1 and H5N8, and subsequent spread along migratory flyways prompted the initiation of several programs in Europe, North America, and Africa to monitor circulation of HPAI and low-pathogenicity precursor viruses (low-pathogenicity avian influenza [LPAI] viruses). Given the costs of maintaining such programs, it is essential to establish best practice for field methodologies to provide robust data for epidemiological interpretation. Here, we use long-term surveillance data from a single site to evaluate the influence of a number of parameters on virus detection and isolation of LPAI viruses. A total of 26,586 samples (oropharyngeal, fecal, and cloacal) collected from wild mallards were screened by real-time PCR, and positive samples were subjected to isolation in embryonated chicken eggs. The LPAI virus detection rate was influenced by the sample type: cloacal/fecal samples showed a consistently higher detection rate and lower cycle threshold (Ct) value than oropharyngeal samples. Molecular detection was more sensitive than isolation, and virus isolation success was proportional to the number of RNA copies in the sample. Interestingly, for a given Ct value, the isolation success was lower in samples from adult birds than in those from juveniles. Comparing the results of specific real-time reverse transcriptase (RRT)-PCRs and of isolation, it was clear that coinfections were common in the investigated birds. The effects of sample type and detection methods warrant some caution in interpretation of the surveillance data.
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Long-Term Effect of Serial Infections with H13 and H16 Low-Pathogenic Avian Influenza Viruses in Black-Headed Gulls. J Virol 2015; 89:11507-22. [PMID: 26339062 DOI: 10.1128/jvi.01765-15] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 08/30/2015] [Indexed: 01/06/2023] Open
Abstract
UNLABELLED Infections of domestic and wild birds with low-pathogenic avian influenza viruses (LPAIVs) have been associated with protective immunity to subsequent infection. However, the degree and duration of immunity in wild birds from previous LPAIV infection, by the same or a different subtype, are poorly understood. Therefore, we inoculated H13N2 (A/black-headed gull/Netherlands/7/2009) and H16N3 (A/black-headed gull/Netherlands/26/2009) LPAIVs into black-headed gulls (Chroicocephalus ridibundus), their natural host species, and measured the long-term immune response and protection against one or two reinfections over a period of >1 year. This is the typical interval between LPAIV epizootics in wild birds. Reinfection with the same virus resulted in progressively less virus excretion, with complete abrogation of virus excretion after two infections for H13 but not H16. However, reinfection with the other virus affected neither the level nor duration of virus excretion. Virus excretion by immunologically naive birds did not differ in total levels of excreted H13 or H16 virus between first- and second-year birds, but the duration of H13 excretion was shorter for second-year birds. Furthermore, serum antibody levels did not correlate with protection against LPAIV infection. LPAIV-infected gulls showed no clinical signs of disease. These results imply that the epidemiological cycles of H13 and H16 in black-headed gulls are relatively independent from each other and depend mainly on infection of first-year birds. IMPORTANCE Low-pathogenic avian influenza viruses (LPAIVs) circulate mainly in wild water birds but are occasionally transmitted to other species, including humans, where they cause subclinical to fatal disease. To date, the effect of LPAIV-specific immunity on the epidemiology of LPAIV in wild birds is poorly understood. In this study, we investigated the effect of H13 and H16 LPAIV infection in black-headed gulls on susceptibility and virus excretion of subsequent infection with the same or the other virus within the same breeding season and between breeding seasons. These are the only two LPAIV hemagglutinin subtypes predominating in this species. The findings suggest that H13 and H16 LPAIV cycles in black-headed gull populations are independent of each other, indicate the importance of first-year birds in LPAIV epidemiology, and emphasize the need for alternatives to avian influenza virus (AIV)-specific serum antibodies as evidence of past LPAIV infection and correlates of protection against LPAIV infection in wild birds.
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Bowman AS, Nolting JM, Massengill R, Baker J, Workman JD, Slemons RD. Influenza A Virus Surveillance in Waterfowl in Missouri, USA, 2005-2013. Avian Dis 2015; 59:303-8. [PMID: 26473682 PMCID: PMC8611411 DOI: 10.1637/11002-121014-reg] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Missouri, United States, is located within the Mississippi Migratory Bird Flyway where wild waterfowl stop to feed and rest during migration and, weather permitting, to overwinter. Historically, Missouri has experienced sporadic influenza A virus (IAV) outbreaks in poultry and commercial swine. The introduction of IAVs from wild, migratory waterfowl is one possible source for the IAV, IAV genomic segments, or both involved in these outbreaks in key agricultural species. During 2005 through 2013, 3984 cloacal swabs were collected from hunter-harvested waterfowl in Missouri as part of an active IAV surveillance effort. Twenty-four avian species were represented in the sample population and 108 (2.7%) of the samples tested positive for IAV recovery. These IAV isolates represented 12 HA and nine NA subtypes and at least 27 distinct HA-NA combinations. An H14 IAV isolate recovered in Missouri during the sample period provided evidence for further establishment of the H14 subtype in North American wild waterfowl and gave proof that the previously rare subtype is more genetically diverse than previously detected. The present surveillance effort also produced IAV isolates that were genomically linked to the highly pathogenic H7N3 IAV strain that emerged in 2012 and caused severe disease in Mexico's domestic poultry. The presence of antigenically diverse IAV's circulating in wild waterfowl in the vicinity of commercial poultry and swine, along with the association of several wild-bird-lineage IAV genomic segments in viruses infecting poultry in North America, justifies continued attention to biosecurity efforts in food animal production systems and ongoing active IAV surveillance in wild birds.
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Affiliation(s)
| | | | - Rose Massengill
- United States Department of Agriculture, Animal and Plant Health Inspection Service, 1715 Southridge Drive, Jefferson City, MO 65109
- Missouri Department of Agriculture, P.O. Box 630, Jefferson City, MO 65102
| | - Joseph Baker
- Missouri Department of Agriculture, P.O. Box 630, Jefferson City, MO 65102
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Pepin KM, Spackman E, Brown JD, Pabilonia KL, Garber LP, Weaver JT, Kennedy DA, Patyk KA, Huyvaert KP, Miller RS, Franklin AB, Pedersen K, Bogich TL, Rohani P, Shriner SA, Webb CT, Riley S. Using quantitative disease dynamics as a tool for guiding response to avian influenza in poultry in the United States of America. Prev Vet Med 2013; 113:376-97. [PMID: 24462191 PMCID: PMC3945821 DOI: 10.1016/j.prevetmed.2013.11.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Revised: 11/22/2013] [Accepted: 11/24/2013] [Indexed: 02/02/2023]
Abstract
Wild birds are the primary source of genetic diversity for influenza A viruses that eventually emerge in poultry and humans. Much progress has been made in the descriptive ecology of avian influenza viruses (AIVs), but contributions are less evident from quantitative studies (e.g., those including disease dynamic models). Transmission between host species, individuals and flocks has not been measured with sufficient accuracy to allow robust quantitative evaluation of alternate control protocols. We focused on the United States of America (USA) as a case study for determining the state of our quantitative knowledge of potential AIV emergence processes from wild hosts to poultry. We identified priorities for quantitative research that would build on existing tools for responding to AIV in poultry and concluded that the following knowledge gaps can be addressed with current empirical data: (1) quantification of the spatio-temporal relationships between AIV prevalence in wild hosts and poultry populations, (2) understanding how the structure of different poultry sectors impacts within-flock transmission, (3) determining mechanisms and rates of between-farm spread, and (4) validating current policy-decision tools with data. The modeling studies we recommend will improve our mechanistic understanding of potential AIV transmission patterns in USA poultry, leading to improved measures of accuracy and reduced uncertainty when evaluating alternative control strategies.
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Affiliation(s)
- K M Pepin
- Department of Biology, Colorado State University, Fort Collins, CO, USA; Fogarty International Center, National Institute of Health, Bethesda, MD, USA.
| | - E Spackman
- Southeast Poultry Research Laboratory, Agricultural Research Service, United States Department of Agriculture, Athens, GA, USA.
| | - J D Brown
- Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA, USA.
| | - K L Pabilonia
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA.
| | - L P Garber
- Centers for Epidemiology and Animal Health, Veterinary Services, Animal and Plant Health Inspection Service, United States Department of Agriculture, Fort Collins, CO, USA.
| | - J T Weaver
- Centers for Epidemiology and Animal Health, Veterinary Services, Animal and Plant Health Inspection Service, United States Department of Agriculture, Fort Collins, CO, USA.
| | - D A Kennedy
- Fogarty International Center, National Institute of Health, Bethesda, MD, USA; Center for Infectious Disease Dynamics, Department of Biology, Pennsylvania State University, State College, PA, USA.
| | - K A Patyk
- Centers for Epidemiology and Animal Health, Veterinary Services, Animal and Plant Health Inspection Service, United States Department of Agriculture, Fort Collins, CO, USA.
| | - K P Huyvaert
- Warner College of Natural Resources, Colorado State University, Fort Collins, CO, USA.
| | - R S Miller
- Centers for Epidemiology and Animal Health, Veterinary Services, Animal and Plant Health Inspection Service, United States Department of Agriculture, Fort Collins, CO, USA.
| | - A B Franklin
- National Wildlife Research Center, Wildlife Services, Animal and Plant Health Inspection Service, United States Department of Agriculture, Fort Collins, CO, USA.
| | - K Pedersen
- National Wildlife Research Center, Wildlife Services, Animal and Plant Health Inspection Service, United States Department of Agriculture, Fort Collins, CO, USA.
| | - T L Bogich
- Fogarty International Center, National Institute of Health, Bethesda, MD, USA; Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA.
| | - P Rohani
- Fogarty International Center, National Institute of Health, Bethesda, MD, USA; Department of Ecology and Evolutionary Biology, Center for the Study of Complex Systems, University of Michigan, Ann Arbor, MI, USA.
| | - S A Shriner
- National Wildlife Research Center, Wildlife Services, Animal and Plant Health Inspection Service, United States Department of Agriculture, Fort Collins, CO, USA.
| | - C T Webb
- Department of Biology, Colorado State University, Fort Collins, CO, USA; Fogarty International Center, National Institute of Health, Bethesda, MD, USA.
| | - S Riley
- Fogarty International Center, National Institute of Health, Bethesda, MD, USA; MRC Centre for Outbreak Analysis and Disease Modelling, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, Norfolk Place, London, UK.
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Huang Y, Wille M, Dobbin A, Robertson GJ, Ryan P, Ojkic D, Whitney H, Lang AS. A 4-year study of avian influenza virus prevalence and subtype diversity in ducks of Newfoundland, Canada. Can J Microbiol 2013; 59:701-8. [PMID: 24102224 DOI: 10.1139/cjm-2013-0507] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The island of Newfoundland, Canada, is at the eastern edge of North America and has migratory bird connections with the continental mainland as well as across the North Atlantic Ocean. Here, we report a 4-year avian influenza virus (AIV) epidemiological study in ducks in the St. John's region of Newfoundland. The overall prevalence of AIV detection in ducks during this study was 7.2%, with American Black Ducks contributing the vast majority of the collected samples and the AIV positives. The juvenile ducks showed a significantly higher AIV detection rate (10.6%) compared with adults (3.4%). Seasonally, AIV prevalence rates were higher in the autumn (8.4%), but positives were still detected in the winter (4.6%). Preliminary serology tests showed a high incidence of previous AIV infection (20/38, 52.6%). A total of 43 viruses were characterized for their HA-NA or HA subtypes, which revealed a large diversity of AIV subtypes and little recurrence of subtypes from year to year. Investigation of the movement patterns of ducks in this region showed that it is a largely non-migratory duck population, which may contribute to the observed pattern of high AIV subtype turnover. Phylogenetic analysis of 4 H1N1 and one H5N4 AIVs showed these viruses were highly similar to other low pathogenic AIV sequences from waterfowl in North America and assigned all gene segments into American-avian clades. Notably, the H1N1 viruses, which were identified in consecutive years, possessed homologous genomes. Such detection of homologous AIV genomes across years is rare, but indicates the role of the environmental reservoir in viral perpetuation.
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Affiliation(s)
- Yanyan Huang
- a Department of Biology, Memorial University of Newfoundland, St. John's, NL A1B 3X9, Canada
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van Dijk JGB, Hoye BJ, Verhagen JH, Nolet BA, Fouchier RAM, Klaassen M. Juveniles and migrants as drivers for seasonal epizootics of avian influenza virus. J Anim Ecol 2013; 83:266-75. [PMID: 24033258 DOI: 10.1111/1365-2656.12131] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Accepted: 07/29/2013] [Indexed: 11/27/2022]
Abstract
Similar to other infectious diseases, the prevalence of low pathogenic avian influenza viruses (LPAIV) has been seen to exhibit marked seasonal variation. However, mechanisms driving this variation in wild birds have yet to be tested. We investigated the validity of three previously suggested drivers for the seasonal dynamics in LPAIV infections in wild birds: (i) host density, (ii) immunologically naïve young and (iii) increased susceptibility in migrants. To address these questions, we sampled a key LPAIV host species, the mallard Anas platyrhynchos, on a small spatial scale, comprehensively throughout a complete annual cycle, measuring both current and past infection (i.e. viral and seroprevalence, respectively). We demonstrate a minor peak in LPAIV prevalence in summer, a dominant peak in autumn, during which half of the sampled population was infected, and no infections in spring. Seroprevalence of antibodies to a conserved gene segment of avian influenza virus (AIV) peaked in winter and again in spring. The summer peak of LPAIV prevalence coincided with the entrance of unfledged naïve young in the population. Moreover, juveniles were more likely to be infected, shed higher quantities of virus and were less likely to have detectable antibodies to AIV than adult birds. The arrival of migratory birds, as identified by stable hydrogen isotope analysis, appeared to drive the autumn peak in LPAIV infection, with both temporal coincidence and higher infection prevalence in migrants. Remarkably, seroprevalence in migrants was substantially lower than viral prevalence throughout autumn migration, further indicating that each wave of migrants amplified local AIV circulation. Finally, while host abundance increased throughout autumn, it peaked in winter, showing no direct correspondence with either of the LPAIV infection peaks. At an epidemiologically relevant spatial scale, we provide strong evidence for the role of migratory birds as key drivers for seasonal epizootics of LPAIV, regardless of their role as vectors of these viruses. This study exemplifies the importance of understanding host demography and migratory behaviour when examining seasonal drivers of infection in wildlife populations.
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Affiliation(s)
- Jacintha G B van Dijk
- Department of Animal Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands
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Jankowski MD, Williams CJ, Fair JM, Owen JC. Birds shed RNA-viruses according to the pareto principle. PLoS One 2013; 8:e72611. [PMID: 23991129 PMCID: PMC3749140 DOI: 10.1371/journal.pone.0072611] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2013] [Accepted: 07/12/2013] [Indexed: 01/12/2023] Open
Abstract
A major challenge in disease ecology is to understand the role of individual variation of infection load on disease transmission dynamics and how this influences the evolution of resistance or tolerance mechanisms. Such information will improve our capacity to understand, predict, and mitigate pathogen-associated disease in all organisms. In many host-pathogen systems, particularly macroparasites and sexually transmitted diseases, it has been found that approximately 20% of the population is responsible for approximately 80% of the transmission events. Although host contact rates can account for some of this pattern, pathogen transmission dynamics also depend upon host infectiousness, an area that has received relatively little attention. Therefore, we conducted a meta-analysis of pathogen shedding rates of 24 host (avian) - pathogen (RNA-virus) studies, including 17 bird species and five important zoonotic viruses. We determined that viral count data followed the Weibull distribution, the mean Gini coefficient (an index of inequality) was 0.687 (0.036 SEM), and that 22.0% (0.90 SEM) of the birds shed 80% of the virus across all studies, suggesting an adherence of viral shedding counts to the Pareto Principle. The relative position of a bird in a distribution of viral counts was affected by factors extrinsic to the host, such as exposure to corticosterone and to a lesser extent reduced food availability, but not to intrinsic host factors including age, sex, and migratory status. These data provide a quantitative view of heterogeneous virus shedding in birds that may be used to better parameterize epidemiological models and understand transmission dynamics.
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Affiliation(s)
- Mark D. Jankowski
- United States Fish and Wildlife Service, Pocatello, Idaho, United States of America
- Department of Zoology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | | | - Jeanne M. Fair
- Biosecurity and Public Health, Los Alamos National Laboratory, Los Alamos, New Mexico, United States of America
| | - Jennifer C. Owen
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, Michigan, United States of America
- Department of Large Animal Clinical Sciences, Michigan State University, East Lansing, Michigan, United States of America
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Latorre-Margalef N, Grosbois V, Wahlgren J, Munster VJ, Tolf C, Fouchier RAM, Osterhaus ADME, Olsen B, Waldenström J. Heterosubtypic immunity to influenza A virus infections in mallards may explain existence of multiple virus subtypes. PLoS Pathog 2013; 9:e1003443. [PMID: 23818849 PMCID: PMC3688562 DOI: 10.1371/journal.ppat.1003443] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Accepted: 05/06/2013] [Indexed: 12/31/2022] Open
Abstract
Wild birds, particularly duck species, are the main reservoir of influenza A virus (IAV) in nature. However, knowledge of IAV infection dynamics in the wild bird reservoir, and the development of immune responses, are essentially absent. Importantly, a detailed understanding of how subtype diversity is generated and maintained is lacking. To address this, 18,679 samples from 7728 Mallard ducks captured between 2002 and 2009 at a single stopover site in Sweden were screened for IAV infections, and the resulting 1081 virus isolates were analyzed for patterns of immunity. We found support for development of homosubtypic hemagglutinin (HA) immunity during the peak of IAV infections in the fall. Moreover, re-infections with the same HA subtype and related prevalent HA subtypes were uncommon, suggesting the development of natural homosubtypic and heterosubtypic immunity (p-value = 0.02). Heterosubtypic immunity followed phylogenetic relatedness of HA subtypes, both at the level of HA clades (p-value = 0.04) and the level of HA groups (p-value = 0.05). In contrast, infection patterns did not support specific immunity for neuraminidase (NA) subtypes. For the H1 and H3 Clades, heterosubtypic immunity showed a clear temporal pattern and we estimated within-clade immunity to last at least 30 days. The strength and duration of heterosubtypic immunity has important implications for transmission dynamics of IAV in the natural reservoir, where immune escape and disruptive selection may increase HA antigenic variation and explain IAV subtype diversity. Influenza A viruses (IAV) infect a range of hosts, with the largest diversity being found in waterfowl, particularly dabbling ducks. In these hosts, IAV causes only mild disease, while viruses that infect other hosts, such as poultry, horses or humans, can cause fatal infections. In fact, all known pandemic flu viruses have contained gene segments that originated in the wild bird reservoir. We sampled a wild population of Mallards over eight seasons and characterized infection histories in 7728 birds. For hemagglutinin (HA) the subtype recoveries indicated that once a Mallard has been infected, re-infection with the same HA subtype is uncommon within the next month, clearly indicating homosubtypic immunity. Moreover, we found evidence for natural heterosubtypic immunity, where phylogenetically related HA subtypes at clade and group levels were less common in re-infections than expected. On the contrary no specific patterns of immunity was found for neuraminidase subtypes. IAVs exist in numerous antigenic subtypes that co-circulate. The strength of heterosubtypic immunity in natural infections provides evidence that HA subtypes compete over hosts and that immune escape may result in positive selection for HA antigenic variation in the virus, and thus explain IAV subtype diversity.
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Affiliation(s)
- Neus Latorre-Margalef
- Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnæus University, Kalmar, Sweden
| | - Vladimir Grosbois
- International Research Center in Agriculture for Development (CIRAD)–UPR AGIRs, Animal and Integrate Risk Management, Campus International de Baillarguet, Montpellier, France
| | - John Wahlgren
- Karolinska Institutet, Department of Microbiology, Tumor and Cell Biology (MTC), Stockholm, Sweden
| | - Vincent J. Munster
- Department of Virology, Erasmus Medical Center, Rotterdam, The Netherlands
- Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Conny Tolf
- Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnæus University, Kalmar, Sweden
| | - Ron A. M. Fouchier
- Department of Virology, Erasmus Medical Center, Rotterdam, The Netherlands
| | | | - Björn Olsen
- Section of Infectious Diseases, Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Jonas Waldenström
- Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnæus University, Kalmar, Sweden
- * E-mail:
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24
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França M, Poulson R, Brown J, Howerth EW, Berghaus RD, Carter D, StallknechtD E. Effect of different routes of inoculation on infectivity and viral shedding of LPAI viruses in mallards. Avian Dis 2013; 56:981-5. [PMID: 23402123 DOI: 10.1637/10151-040812-resnote.1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We studied the effect of different routes of inoculation on the infectivity and duration of viral shedding in mallards (Anas platyrhynchos) infected with wild bird-origin low pathogenic avian influenza viruses (LPAIVs). One-month-old mallards were inoculated with 10(6) median embryo infectious doses of either A/mallard/MN/199106/99 (H3N8) or A/mallard/MN/355779/00 (H5N2) via 1 of 5 different routes: intranasal (IN), intratracheal (IT), intraocular (IO), intracloacal (IC), or intra-ingluvial (II). Birds in all routes of inoculation groups became infected with LPAIV as detected by virus isolation, real time reverse transcription polymerase chain reaction, and serology. Mallards in different route of inoculation groups had similar viral shedding through oropharynx and cloaca from 1 day postinoculation (dpi). The peak of oropharyngeal (OP) viral shedding was reached between 2 and 3 dpi in all routes of inoculation groups infected with either virus. The peak of cloacal (CL) viral excretion was reached between 2 and 3 dpi in all routes of inoculation groups infected with H3N8 LPAIV and in the IO-, IC-, and II-inoculated groups infected with H5N2 LPAIV, with a delayed and shorter peak for the IN- and IT-inoculated groups. The birds inoculated via the II route had more productive OP and CL viral shedding after infection with either LPAIV, as evidenced by higher number of swabs testing positive over the study period. In conclusion, mallards can be infected with LPAIV by various routes of inoculation, and this corroborates their high susceptibility to infection by these viruses.
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Affiliation(s)
- M França
- Department of Pathology, College of Veterinary Medicine, University of Georgia, 501 DW Brooks Drive, Athens, GA 30602, USA
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25
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França M, Stallknecht DE, Poulson R, Brown J, Howerth EW. The pathogenesis of low pathogenic avian influenza in mallards. Avian Dis 2013; 56:976-80. [PMID: 23402122 DOI: 10.1637/10153-040812-resnote.1] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Mallards are important natural hosts involved in the epidemiology of low pathogenic avian influenza viruses (LPAIVs). LPAIVs are mainly transmitted by a fecal-oral route and are excreted in high concentrations in the feces. We investigated the pathology, viral antigen distribution, and the expression of alpha2,3 sialic acid (SA) influenza virus receptors in mallards after intranasal inoculation with A/Mallard/MN/199106/99 (H3N8) or A/Mallard/MN/355779/00 (H5N2). Gross lesions were not observed. Avian influenza virus (AIV) nucleoprotein (NP) antigen was detected in rare epithelial cells of the larynx and trachea only at 1-day postinoculation (dpi) in the birds infected with H3N8 LPAIV, but infection with either virus was associated with lymphocytic tracheitis and laryngitis on 1 and 2 dpi. AIV NP antigen was detected in enterocytes of the lower intestine from 1 to 4 dpi and in epithelial cells of the bursa of Fabricius from 2 to 3 dpi in birds infected with either virus. Oropharyngeal and cloacal viral shedding was detected from 1 dpi, with higher cloacal viral shedding detected at 2 and 3 dpi with both viruses. Mallards abundantly expressed alpha2,3 sialic acid receptors in epithelial cells of the respiratory tract, lower intestine, and bursa of Fabricius. Some infected birds had decreased alpha2,3 sialic acid expression in epithelial cells of the bursa of Fabricius and in enterocytes of the ceca and colon. In conclusion, the main sites of LPAIV replication in mallards are the enterocytes of the lower intestinal tract and epithelial cells of the bursa of Fabricius in the first days after infection, when these birds are shedding AIV in high titers in the feces.
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Affiliation(s)
- M França
- Department of Pathology, University of Georgia, 501 DW Brooks Drive, Athens, GA 30602, USA
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26
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Hénaux V, Parmley J, Soos C, Samuel MD. Estimating transmission of avian influenza in wild birds from incomplete epizootic data: implications for surveillance and disease spread. J Appl Ecol 2013. [DOI: 10.1111/1365-2664.12031] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Viviane Hénaux
- Department of Forest and Wildlife Ecology; University of Wisconsin; Madison; WI; 53706; USA
| | - Jane Parmley
- Canadian Cooperative Wildlife Health Centre, University of Guelph; Guelph; ON; N1G 2W1; Canada
| | - Catherine Soos
- Science & Technology Branch; Environment Canada; Saskatoon; SK; S7N 0X4; Canada
| | - Michael D. Samuel
- U. S. Geological Survey, Wisconsin Cooperative Wildlife Research Unit; University of Wisconsin; Madison; WI; 53706; USA
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27
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Pepin KM, VanDalen KK, Mooers NL, Ellis JW, Sullivan HJ, Root JJ, Webb CT, Franklin AB, Shriner SA. Quantification of heterosubtypic immunity between avian influenza subtypes H3N8 and H4N6 in multiple avian host species. J Gen Virol 2012; 93:2575-2583. [PMID: 22956733 DOI: 10.1099/vir.0.045427-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Low-pathogenicity avian influenza virus (LPAIV) can lead to epizootics that cause economic losses in poultry or the emergence of human-infectious strains. LPAIVs experience a complex immunity landscape as they are endemic in numerous host species, and many antigenically distinct strains co-circulate. Prevention and control of emergence of detrimental strains requires an understanding of infection/transmission characteristics of the various subtypes in different hosts, including interactions between subtypes. In order to develop analytical frameworks for examining control efficacy, quantification of heterosubtypic immunity interactions is fundamental. However, these data are scarce, especially for wild avian subtypes in natural hosts. Consequently, in this study, three host species (mallards, quail and pheasants) were infected with two LPAIV subtypes isolated from wild birds: H3N8 and H4N6. The recovered hosts were also reinfected with the alternate subtype to measure the effects of heterosubtypic immunity. Oropharyngeal and cloacal swabs were collected and viral RNA load was quantified by real-time RT-PCR. For secondary infections in recovered hosts, peak viral load was up to four orders of magnitude lower and shedding length was up to 4 days shorter. However, both the magnitude and presence of heterosubtypic immunity varied across specific host species/subtype combinations. Using a mathematical model of virus replication, the variation in virus replication dynamics due to host individuals was quantified. It was found that accounting for individual heterogeneity is important for drawing accurate conclusions about treatment effects. These results are relevant for developing epidemiological models to inform control practices and for analysing virus replication data.
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Affiliation(s)
- K M Pepin
- Colorado State University, Fort Collins, CO, USA
- Fogarty International Center, Bethesda, MD, USA
| | - K K VanDalen
- National Wildlife Research Center, USDA Wildlife Services, Fort Collins, CO, USA
| | - N L Mooers
- National Wildlife Research Center, USDA Wildlife Services, Fort Collins, CO, USA
| | - J W Ellis
- National Wildlife Research Center, USDA Wildlife Services, Fort Collins, CO, USA
| | - H J Sullivan
- National Wildlife Research Center, USDA Wildlife Services, Fort Collins, CO, USA
| | - J J Root
- National Wildlife Research Center, USDA Wildlife Services, Fort Collins, CO, USA
| | - C T Webb
- Colorado State University, Fort Collins, CO, USA
| | - A B Franklin
- National Wildlife Research Center, USDA Wildlife Services, Fort Collins, CO, USA
| | - S A Shriner
- National Wildlife Research Center, USDA Wildlife Services, Fort Collins, CO, USA
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28
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Avian influenza viruses in wild birds at the Jeziorsko reservoir in Poland in 2008-2010. Pol J Vet Sci 2012; 15:323-8. [PMID: 22844711 DOI: 10.2478/v10181-011-0150-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
During a 3-year surveillance study for avian influenza virus (AIV) infections at the Jeziorsko reservoir in central Poland, 549 oropharyngeal or cloacal swabs from 366 birds of 14 species belonging to 3 orders (Anseriformes, Charadriiformes and Gruiformes) were tested. AIV was detected in 14 birds (3.8%): Common Teals (12x), Mallard (1x) and Garganey (1x). Three potentially dangerous H5 AIV were detected in Common Teals (2x) and Garganey (1x) but all of them revealed a low pathogenic pathotype. A unique cleavage site amino acid motif PQREIR*GLF was found in one H5 isolate from a Garganey.
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29
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Reis A, Stallknecht D, Ritz C, García M. Tenacity of low-pathogenic avian influenza viruses in different types of poultry litter. Poult Sci 2012; 91:1745-50. [DOI: 10.3382/ps.2011-01625] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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30
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Effect of age on the pathogenesis and innate immune responses in Pekin ducks infected with different H5N1 highly pathogenic avian influenza viruses. Virus Res 2012; 167:196-206. [DOI: 10.1016/j.virusres.2012.04.015] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Revised: 04/11/2012] [Accepted: 04/27/2012] [Indexed: 11/18/2022]
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31
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Lebarbenchon C, Sreevatsan S, Lefèvre T, Yang M, Ramakrishnan MA, Brown JD, Stallknecht DE. Reassortant influenza A viruses in wild duck populations: effects on viral shedding and persistence in water. Proc Biol Sci 2012; 279:3967-75. [PMID: 22859590 DOI: 10.1098/rspb.2012.1271] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Wild ducks of the genus Anas represent the natural hosts for a large genetic diversity of influenza A viruses. In these hosts, co-infections with different virus genotypes are frequent and result in high rates of genetic reassortment. Recent genomic data have provided information regarding the pattern and frequency of these reassortant viruses in duck populations; however, potential consequences on viral shedding and maintenance in the environment have not been investigated. On the basis of full-genome sequencing, we identified five virus genotypes, in a wild duck population in northwestern Minnesota (USA), that naturally arose from genetic reassortments. We investigated the effects of influenza A virus genotype on the viral shedding pattern in Mallards (Anas platyrhynchos) and the duration of infectivity in water, under different temperature regimens. Overall, we found that variation in the viral genome composition of these isolates had limited effects on duration, extent and pattern of viral shedding, as well as on the reduction of infectivity in water over time. These results support that, in wild ducks, functionally equivalent gene segments could be maintained in virus populations with no fitness costs when genetic reassortments occur.
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Affiliation(s)
- Camille Lebarbenchon
- Department of Population Health, College of Veterinary Medicine, Southeastern Cooperative Wildlife Disease Study, University of Georgia, Athens, GA 30602, USA.
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32
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Disease dynamics and bird migration--linking mallards Anas platyrhynchos and subtype diversity of the influenza A virus in time and space. PLoS One 2012; 7:e35679. [PMID: 22536424 PMCID: PMC3335010 DOI: 10.1371/journal.pone.0035679] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2011] [Accepted: 03/22/2012] [Indexed: 11/19/2022] Open
Abstract
The mallard Anas platyrhynchos is a reservoir species for influenza A virus in the northern hemisphere, with particularly high prevalence rates prior to as well as during its prolonged autumn migration. It has been proposed that the virus is brought from the breeding grounds and transmitted to conspecifics during subsequent staging during migration, and so a better understanding of the natal origin of staging ducks is vital to deciphering the dynamics of viral movement pathways. Ottenby is an important stopover site in southeast Sweden almost halfway downstream in the major Northwest European flyway, and is used by millions of waterfowl each year. Here, mallards were captured and sampled for influenza A virus infection, and positive samples were subtyped in order to study possible links to the natal area, which were determined by a novel approach combining banding recovery data and isotopic measurements (δ2H) of feathers grown on breeding grounds. Geographic assignments showed that the core natal areas of studied mallards were in Estonia, southern and central Finland, and northwestern Russia. This study demonstrates a clear temporal succession of latitudes of natal origin during the course of autumn migration. We also demonstrate a corresponding and concomitant shift in virus subtypes. Acknowledging that these two different patterns were based in part upon different data, a likely interpretation worth further testing is that the early arriving birds with more proximate origins have different influenza A subtypes than the more distantly originating late autumn birds. If true, this knowledge would allow novel insight into the origins and transmission of the influenza A virus among migratory hosts previously unavailable through conventional approaches.
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33
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Farnsworth ML, Miller RS, Pedersen K, Lutman MW, Swafford SR, Riggs PD, Webb CT. Environmental and demographic determinants of avian influenza viruses in waterfowl across the contiguous United States. PLoS One 2012; 7:e32729. [PMID: 22427870 PMCID: PMC3299682 DOI: 10.1371/journal.pone.0032729] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2011] [Accepted: 02/01/2012] [Indexed: 11/19/2022] Open
Abstract
Outbreaks of avian influenza in North American poultry have been linked to wild waterfowl. A first step towards understanding where and when avian influenza viruses might emerge from North American waterfowl is to identify environmental and demographic determinants of infection in their populations. Laboratory studies indicate water temperature as one determinant of environmental viral persistence and we explored this hypothesis at the landscape scale. We also hypothesized that the interval apparent prevalence in ducks within a local watershed during the overwintering season would influence infection probabilities during the following breeding season within the same local watershed. Using avian influenza virus surveillance data collected from 19,965 wild waterfowl across the contiguous United States between October 2006 and September 2009 We fit Logistic regression models relating the infection status of individual birds sampled on their breeding grounds to demographic characteristics, temperature, and interval apparent prevalence during the preceding overwintering season at the local watershed scale. We found strong support for sex, age, and species differences in the probability an individual duck tested positive for avian influenza virus. In addition, we found that for every seven days the local minimum temperature fell below zero, the chance an individual would test positive for avian influenza virus increased by 5.9 percent. We also found a twelve percent increase in the chance an individual would test positive during the breeding season for every ten percent increase in the interval apparent prevalence during the prior overwintering season. These results suggest that viral deposition in water and sub-freezing temperatures during the overwintering season may act as determinants of individual level infection risk during the subsequent breeding season. Our findings have implications for future surveillance activities in waterfowl and domestic poultry populations. Further study is needed to identify how these drivers might interact with other host-specific infection determinants, such as species phylogeny, immunological status, and behavioral characteristics.
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Affiliation(s)
- Matthew L Farnsworth
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Service, Centers for Epidemiology and Animal Health, Fort Collins, Colorado, United States of America.
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34
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Lebarbenchon C, Yang M, Keeler SP, Ramakrishnan MA, Brown JD, Stallknecht DE, Sreevatsan S. Viral replication, persistence in water and genetic characterization of two influenza A viruses isolated from surface lake water. PLoS One 2011; 6:e26566. [PMID: 22028909 PMCID: PMC3197669 DOI: 10.1371/journal.pone.0026566] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2011] [Accepted: 09/29/2011] [Indexed: 11/18/2022] Open
Abstract
Water-borne transmission has been suggested as an important transmission mechanism for Influenza A (IA) viruses in wild duck populations; however, relatively few studies have attempted to detect IA viruses from aquatic habitats. Water-isolated viruses have rarely been genetically characterized and evaluation for persistence in water and infectivity in natural hosts has never been documented. In this study, we focused on two IA viruses (H3N8 and H4N6 subtypes) isolated from surface lake water in Minnesota, USA. We investigated the relative prevalence of the two virus subtypes in wild duck populations at the sampling site and their genetic relatedness to IA viruses isolated in wild waterbirds in North America. Viral persistence under different laboratory conditions (temperature and pH) and replication in experimentally infected Mallards (Anas platyrhynchos) were also characterized. Both viruses were the most prevalent subtype one year following their isolation in lake water. The viruses persisted in water for an extended time period at constant temperature (several weeks) but infectivity rapidly reduced under multiple freeze-thaw cycles. Furthermore, the two isolates efficiently replicated in Mallards. The complete genome characterization supported that these isolates originated from genetic reassortments with other IA viruses circulating in wild duck populations during the year of sampling. Based on phylogenetic analyses, we couldn't identify genetically similar viruses in duck populations in the years following their isolation from lake water. Our study supports the role for water-borne transmission for IA viruses but also highlights that additional field and experimental studies are required to support inter-annual persistence in aquatic habitats.
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Affiliation(s)
- Camille Lebarbenchon
- Southeastern Cooperative Wildlife Disease Study, Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, Georgia, United States of America.
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35
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Effects of infection-induced migration delays on the epidemiology of avian influenza in wild mallard populations. PLoS One 2011; 6:e26118. [PMID: 22028812 PMCID: PMC3196538 DOI: 10.1371/journal.pone.0026118] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2011] [Accepted: 09/19/2011] [Indexed: 11/23/2022] Open
Abstract
Wild waterfowl populations form a natural reservoir of Avian Influenza (AI) virus, and fears exist that these birds may contribute to an AI pandemic by spreading the virus along their migratory flyways. Observational studies suggest that individuals infected with AI virus may delay departure from migratory staging sites. Here, we explore the epidemiological dynamics of avian influenza virus in a migrating mallard (Anas platyrhynchos) population with a specific view to understanding the role of infection-induced migration delays on the spread of virus strains of differing transmissibility. We develop a host-pathogen model that combines the transmission dynamics of influenza with the migration, reproduction and mortality of the host bird species. Our modeling predicts that delayed migration of individuals influences both the timing and size of outbreaks of AI virus. We find that (1) delayed migration leads to a lower total number of cases of infection each year than in the absence of migration delay, (2) when the transmission rate of a strain is high, the outbreak starts at the staging sites at which birds arrive in the early part of the fall migration, (3) when the transmission rate is low, infection predominantly occurs later in the season, which is further delayed when there is a migration delay. As such, the rise of more virulent AI strains in waterfowl could lead to a higher prevalence of infection later in the year, which could change the exposure risk for farmed poultry. A sensitivity analysis shows the importance of generation time and loss of immunity for the effect of migration delays. Thus, we demonstrate, in contrast to many current transmission risk models solely using empirical information on bird movements to assess the potential for transmission, that a consideration of infection-induced delays is critical to understanding the dynamics of AI infection along the entire flyway.
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36
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El Zowalaty ME, Abin M, Chander Y, Redig PT, Goyal SM. Improved Method for the Isolation and Sub-Typing of Avian Influenza Viruses from Oropharyngeal Samples of Ducks. Avian Dis 2011; 55:439-42. [DOI: 10.1637/9677-020311-reg.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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37
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Hoye BJ, Fouchier RAM, Klaassen M. Host behaviour and physiology underpin individual variation in avian influenza virus infection in migratory Bewick's swans. Proc Biol Sci 2011; 279:529-34. [PMID: 21733894 DOI: 10.1098/rspb.2011.0958] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
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.
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Affiliation(s)
- Bethany J Hoye
- Department of Animal Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB Wageningen, The Netherlands.
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Costa TP, Brown JD, Howerth EW, Stallknecht DE. Variation in viral shedding patterns between different wild bird species infected experimentally with low-pathogenicity avian influenza viruses that originated from wild birds. Avian Pathol 2011; 40:119-24. [PMID: 21500030 DOI: 10.1080/03079457.2010.540002] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Hoye BJ, Munster VJ, Nishiura H, Klaassen M, Fouchier RAM. Surveillance of wild birds for avian influenza virus. Emerg Infect Dis 2011; 16:1827-34. [PMID: 21122209 PMCID: PMC3294547 DOI: 10.3201/eid1612.100589] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
TOC Summary: A targeted, hypothesis-based approach and local surveys over broad geographic areas are needed. Recent demand for increased understanding of avian influenza virus in its natural hosts, together with the development of high-throughput diagnostics, has heralded a new era in wildlife disease surveillance. However, survey design, sampling, and interpretation in the context of host populations still present major challenges. We critically reviewed current surveillance to distill a series of considerations pertinent to avian influenza virus surveillance in wild birds, including consideration of what, when, where, and how many to sample in the context of survey objectives. Recognizing that wildlife disease surveillance is logistically and financially constrained, we discuss pragmatic alternatives for achieving probability-based sampling schemes that capture this host–pathogen system. We recommend hypothesis-driven surveillance through standardized, local surveys that are, in turn, strategically compiled over broad geographic areas. Rethinking the use of existing surveillance infrastructure can thereby greatly enhance our global understanding of avian influenza and other zoonotic diseases.
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Affiliation(s)
- Bethany J Hoye
- Netherlands Institute for Ecology, Nieuwersluis, the Netherlands.
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Nemeth NM, Thomas NO, Orahood DS, Anderson TD, Oesterle PT. Shedding and serologic responses following primary and secondary inoculation of house sparrows (Passer domesticus) and European starlings (Sturnus vulgaris) with low-pathogenicity avian influenza virus. Avian Pathol 2011; 39:411-8. [PMID: 20954019 DOI: 10.1080/03079457.2010.513043] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Waterfowl and shorebirds are well-recognized natural reservoirs of low-pathogenicity avian influenza viruses (LPAIV); however, little is known about the role of passerines in avian influenza virus ecology. Passerines are abundant, widespread, and commonly come into contact with free-ranging birds as well as captive game birds and poultry. We inoculated and subsequently challenged house sparrows (Passer domesticus) and European starlings (Sturnus vulgaris) with wild-bird origin LPAIV H3N8 to evaluate their potential role in transmission. Oropharyngeal shedding was short lived, and was detected in more starlings (97.2%) than sparrows (47.2%; n=36 of each). Cloacal shedding was rare in both species (8.3%; n=36 of each) and no cage-mate transmission occurred. Infectious LPAIV was cultured from oropharyngeal and cloacal swabs and gastrointestinal and respiratory tissues from both species. Seroconversion was detected as early as 3 days post inoculation (d.p.i.) (16.7% of sparrows and 0% of starlings; n=6 each); 50% of these individuals seroconverted by 5 d.p.i., and nearly all birds (97%; n=35) seroconverted by 28 d.p.i. In general, pre-existing homologous immunity led to reduced shedding and increased antibody levels within 7 days of challenge. Limited shedding and lack of cage-mate transmission suggest that passerines are not significant reservoirs of LPAIV, although species differences apparently exist. Passerines readily and consistently seroconverted to LPAIV, and therefore inclusion of passerines in epidemiological studies of influenza outbreaks in wildlife and domestic animals may provide further insight into the potential involvement of passerines in avian influenza virus transmission ecology.
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Affiliation(s)
- Nicole M Nemeth
- USDA/APHIS/WS/National Wildlife Research Center, Fort Collins, CO, USA.
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Hoye BJ, Munster VJ, Nishiura H, Fouchier RAM, Madsen J, Klaassen M. Reconstructing an annual cycle of interaction: natural infection and antibody dynamics to avian influenza along a migratory flyway. OIKOS 2010. [DOI: 10.1111/j.1600-0706.2010.18961.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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VanDalen KK, Franklin AB, Mooers NL, Sullivan HJ, Shriner SA. Shedding light on avian influenza H4N6 infection in mallards: modes of transmission and implications for surveillance. PLoS One 2010; 5:e12851. [PMID: 20877466 PMCID: PMC2942899 DOI: 10.1371/journal.pone.0012851] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2010] [Accepted: 08/27/2010] [Indexed: 11/18/2022] Open
Abstract
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.
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Affiliation(s)
- Kaci K VanDalen
- National Wildlife Research Center, Wildlife Services, Animal and Plant Health Inspection Service, United States Department of Agriculture, Fort Collins, Colorado, USA.
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Abstract
AbstractAvian influenza (AI) virus is one of the most important diseases of the poultry industry around the world. The virus has a broad host range in birds and mammals, although the natural reservoir is wild birds where it typically causes an asymptomatic to mild infection. The virus in poultry can cause a range of clinical diseases and is defined either as low pathogenic AI (LPAI) or highly pathogenic AI (HPAI) depending on the type of disease it causes in chickens. Viruses that replicate primarily on mucosal surfaces and cause mild disease with low mortality are termed LPAI. Viruses that replicate on mucosal surfaces and systemically and cause severe disease with a mortality rate of 75% or greater in experimentally infected chickens are referred to as HPAI. A virus that is highly pathogenic in chickens may infect but result in a completely different disease and replication pattern in other host species. Outbreaks of HPAI have been relatively uncommon around the world in the last 50 years and have had limited spread within a country or region with one major exception, Asian lineage H5N1 that was first identified in 1996. This lineage of virus has spread to over 60 countries and has become endemic in poultry in at least four countries. AI virus also represents a public health threat, with some infected humans having severe disease and with a high case fatality rate. AI remains a difficult disease to control because of the highly infectious nature of the virus and the interface of domestic and wild animals. A better understanding of the disease and its transmission is important for control.
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