Autochthonous circulation of Saint Louis encephalitis and West Nile viruses in the Province of La Rioja, Argentina

BATALLAN, GP; KONIGHEIM, BS; QUAGLIA, AI; RIVAROLA, E; BERANEK, M; TAURO, BS; FLORES, SF; LAURITO, M; ALMIRÓN, W.R.; CONTIGIANI, MS; VISINTIN, AM

Revista Argentina de Microbiología

ELSEVIER

Año: 2021

0325-7541

St. Louis encephalitis (SLEV) and West Nile (WNV) arboviruses, which circulate inArgentina, are maintained in enzootic transmission cycles involving Culex mosquitoes (vectors)and birds belonging to orders Passeriformes and Columbiformes (amplifier hosts). The objectiveof this work was to determine the circulation of both viruses among wild birds in a semiaridecosystem in the Province of La Rioja through a serologic survey. During spring 2013 and fall2014, a total of 326 wild birds belonging to 41 species were captured in areas close to thecities of La Rioja and Chilecito, in the Province of La Rioja. While exposure to SLEV and WNVwas analyzed in birds? serum through neutralizing antibody detection, viral circulation wasestimated through apparent seroprevalence of neutralizing antibodies. The exposure of theavian community to viruses was 3.02% for SLEV and 1.89% for WNV, while 1.19% corresponded tocoinfections. Our study confirms for the first time the circulation of SLEV and WNV in wild birdsin the Province of La Rioja. Moreover, it is the first study to register neutralizing antibodiesfor flavivirus in the species Leptotila verreauxi (White-tipped Dove) (WNV) and Melanerpescactorum (White-fronted Woodpecker) (SLEV). These results suggest that in semiarid ecosystemsfrom northwestern Argentina the requirements and conditions for amplification and enzooticmaintenance of SLEV and WNV would be present.