title: ECOLOGICAL DETERMINANTS OF AVIAN INFLUENZA VIRUS, WEST NILE VIRUS, AND AVIAN PARAMYXOVIRUS INFECTION AND ANTIBODY STATUS IN BLUE-WINGED TEAL (ANAS DISCORS) IN THE CANADIAN PRAIRIES.
abstract: The Canadian prairies are one of the most important breeding and staging areas for migratory waterfowl in North America. Hundreds of thousands of waterfowl of numerous species from multiple flyways converge in and disperse from this region annually; therefore this region may be a key area for potential intra- and interspecific spread of infectious pathogens among migratory waterfowl in the Americas. Using Blue-winged Teal (Anas discors, BWTE), which have the most extensive migratory range among waterfowl species, we investigated ecologic risk factors for infection and antibody status to avian influenza virus (AIV), West Nile virus (WNV), and avian paramyxovirus-1 (APMV-1) in the three prairie provinces (Alberta, Saskatchewan, and Manitoba) prior to fall migration. We used generalized linear models to examine infection or evidence of exposure in relation to host (age, sex, body condition, exposure to other infections), spatiotemporal (year, province), population-level (local population densities of BWTE, total waterfowl densities), and environmental (local pond densities) factors. The probability of AIV infection in BWTE was associated with host factors (e.g., age and antibody status), population-level factors (e.g., local BWTE population density), and year. An interaction between age and AIV antibody status showed that hatch year birds with antibodies to AIV were more likely to be infected, suggesting an antibody response to an active infection. Infection with AIV was positively associated with local BWTE density, supporting the hypothesis of density-dependent transmission. The presence of antibodies to WNV and APMV-1 was positively associated with age and varied among years. Furthermore, the probability of being WNV antibody positive was positively associated with pond density rather than host population density, likely because ponds provide suitable breeding habitat for mosquitoes, the primary vectors for transmission. Our findings highlight the importance of spatiotemporal, environmental, and host factors at the individual and population levels, all of which may influence dynamics of these and other viruses in wild waterfowl populations.
authors.affiliation: 1  Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4, Canada.|2  Wildlife Conservation Society, Greater Madidi-Tambopata Landscape Conservation Program, Casilla 3-35181, La Paz, Bolivia.|3  Environment Canada, Science & Technology Branch, 115 Perimeter Road, Saskatoon, Saskatchewan S7N 0X4, Canada.
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Nallar
authors.affiliation: 3  Environment Canada, Science & Technology Branch, 115 Perimeter Road, Saskatoon, Saskatchewan S7N 0X4, Canada.|8  These authors contributed equally to this study.
authors.forename: Zsuzsanna
authors.initials: Z
authors.lastname: Papp
authors.affiliation: 1  Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4, Canada.|4  Canadian Wildlife Health Cooperative, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4, Canada.
authors.forename: Frederick A
authors.initials: FA
authors.lastname: Leighton
authors.affiliation: 5  Department of Large Animal Clinical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4, Canada.
authors.forename: Tasha
authors.initials: T
authors.lastname: Epp
authors.affiliation: 6  National Centre for Foreign Animal Disease, Canadian Food Inspection Agency, Winnipeg, Manitoba R3L 3M4, Canada.
authors.forename: John
authors.initials: J
authors.lastname: Pasick
authors.affiliation: 6  National Centre for Foreign Animal Disease, Canadian Food Inspection Agency, Winnipeg, Manitoba R3L 3M4, Canada.
authors.forename: Yohannes
authors.initials: Y
authors.lastname: Berhane
authors.affiliation: 7  Public Health Agency of Canada, National Microbiology Laboratory, Zoonotic Diseases and Special Pathogens, Winnipeg, Manitoba R3E 3R2, Canada.
authors.forename: Robbin
authors.initials: R
authors.lastname: Lindsay
authors.affiliation: 1  Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4, Canada.|3  Environment Canada, Science & Technology Branch, 115 Perimeter Road, Saskatoon, Saskatchewan S7N 0X4, Canada.
authors.forename: Catherine
authors.initials: C
authors.lastname: Soos
mesh_terms: D000416:Alberta / Q000453:epidemiology; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D001715:Bird Diseases / Q000453:epidemiology / Q000821:virology*; D004372:Ducks / Q000821:virology; D005260:Female; D005585:Influenza in Birds / Q000453:epidemiology*; D016014:Linear Models; D008297:Male; D008350:Manitoba / Q000453:epidemiology; D008954:Models, Biological; D009521:Newcastle Disease / Q000453:epidemiology*; D009522:Newcastle disease virus / Q000276:immunology; D009975:Orthomyxoviridae / Q000276:immunology; D061005:Ponds; D015995:Prevalence; D012307:Risk Factors; D012525:Saskatchewan / Q000453:epidemiology; D014901:West Nile Fever / Q000453:epidemiology / Q000662:veterinary*; D014902:West Nile virus / Q000276:immunology
chemical_list: D000914:Antibodies, Viral
keywords: Avian influenza; Blue-winged Teal; West Nile virus; avian paramyxovirus; disease ecology; migratory waterfowl; molecular diagnostics; serology