Prevalence of West Nile virus and Saint Louis Encephalitis virus antibodies in Argentine birds of prey

LUIS ADRÍAN DIAZ; MARTA SILVIA CONTIGIANI; AGUSTÍN IE. QUAGLIA; HERNÁN ARGIBAY; MIGUEL D. SAGGESE

Fort Collins, Colorado

Encuentro; Raptor Research Foundation Annual Meeting; 2010

Raptor Research Foundation

Birds of prey are highly susceptible to West Nile virus (WNV, family Flaviviridae, genus Flavivirus). The ongoing spread of WNV in Latin America raises concern about the possible effect of this virus in Neotropical birds of prey. More than 116 species of diurnal and nocturnal birds of prey inhabit the Neotropics The potential impact of WNV infection on naive populations of threatened or endangered birds of prey in this region may be considerable. The recent detection of WNV in Argentina has raised concern about the potential impact of this virus on endangered naïve raptors populations, such as eagles and other endangered species, present in this country. Therefore, we investigated the prevalence of WNV and Saint Louis encephalitis virus (SLEV) antibodies in blood of 17 species of raptors from Cordoba and Misiones provinces, Argentina. Samples from 41 birds were analyzed by plaque reduction neutralization test (PRNT). From this initial pool of birds, only two individuals of the endangered Argentine Crowned Eagle (Harpyhaliaetus coronatus) were found to be seropositive one for each virus. Titers >1:80 suggest recent infection in both birds. Seropositive birds reside in Iguazú, Misiones province, northeastern Argentina (SLEV) and Huerta Grande, Córdoba province, central Argentina (WNV). These results agree with the previously known spatial distribution of these flaviviruses in this country. A high percentage of the investigated birds (97.6%) were apparently never exposed to these viruses. This lack of previous exposure to WNV and SLEV and protective antibodies suggest that the endangered Crowned Eagle and other threatened species of raptors inhabiting northeastern Argentina may be at high risk if exposed to the deleterious effects of these flaviviruses.