ST. LOUIS ENCEPHALITIS VIRUS TRANSMISSION BY CULEX QUINQUEFASCIATUS MOSQUITOES COLLECTED IN CORDOBA CITY

FLORES FS; DIAZ LA; ALMIRÓN WR; CONTIGIANI MS

Buenos Aires

Congreso; ARGENTINE SOCIETY OF BIOLOGY; 2008

St. Louis encephalitis virus (SLEV) is maintenance by transmission cylces including mosquitoes and birds. Culex quinquefasciatus mosquitoes was incriminated as a potential vector for SLEV transmission in Córdoba city. The aim of this project was to evaluate vectorial transmission of SLEV by Cx. quinquefasciatus mosquitoes collected in Cordoba. Mosquitoes females were fed on 3-4-day-old viremic chicks, containing 3.5 log pfu/ml, previously inoculated with SLEV 78V-6507 strain isolated from Cx. quinquefasciatus in Santa Fe in 1978. Those mosquitoes were incubated at room temperature during 15 days, after that were re-feeding over non viremic chicks. Virus detection was carried out by plaque forming unit/ml (pfu/ml) whit monolayer cultures of Vero cells under agarosa. Overall, 90.9% (80/88) mosquitoes became infected showing their susceptibility to the infection by SLEV. In a preliminary essay the non-infected chicks on which mosquitoes were re-feeding developed viremias between 3 and 5 log pfu/ml. Those results indicate the ability of Cx. quinquefasciatus mosquitoes to transmit SLEV and contribute to the knowledge of this specie as a competent vector for SLEV in the center region of Argentina.