title: West Nile virus outbreak in North American owls, Ontario, 2002.
abstract: From July to September 2002, an outbreak of West Nile virus (WNV) caused a high number of deaths in captive owls at the Owl Foundation, Vineland, Ontario, Canada. Peak death rates occurred in mid-August, and the epidemiologic curve resembled that of corvids in the surrounding Niagara region. The outbreak occurred in the midst of a louse fly (Icosta americana, family Hippoboscidae) infestation. Of the flies tested, 16 (88.9 %) of 18 contained WNV RNA. Species with northern native breeding range and birds >1 year of age were at significantly higher risk for WNV-related deaths. Species with northern native breeding range and of medium-to-large body size were at significantly higher risk for exposure to WNV. Taxonomic relations (at the subfamily level) did not significantly affect exposure to WNV or WNV-related deaths. Northern native breeding range and medium-to-large body size were associated with earlier death within the outbreak period. Of the survivors, 69 (75.8 %) of 91 were seropositive for WNV.
authors.affiliation: University of Guelph, Guelph, Ontario, Canada. agancz@uoguelph.ca
authors.forename: Ady Y
authors.initials: AY
authors.lastname: Gancz
authors.forename: Ian K
authors.initials: IK
authors.lastname: Barker
authors.forename: Robbin
authors.initials: R
authors.lastname: Lindsay
authors.forename: Antonia
authors.initials: A
authors.lastname: Dibernardo
authors.forename: Katherine
authors.initials: K
authors.lastname: McKeever
authors.forename: Bruce
authors.initials: B
authors.lastname: Hunter
mesh_terms: D000818:Animals; D001715:Bird Diseases / Q000453:epidemiology* / Q000821:virology; D004175:Diptera / Q000821:virology; D004196:Disease Outbreaks / Q000662:veterinary*; D004199:Disease Vectors; D004777:Environment; D009864:Ontario / Q000453:epidemiology; D012307:Risk Factors; D020305:Strigiformes / Q000821:virology*; D014901:West Nile Fever / Q000453:epidemiology / Q000662:veterinary*