[The Wesselsbron virus, a new arbovirus for Madagascar].

Wesselsbron virus, an African arbovirus group flavivirus, has been isolated in 1989 for the first time in MADAGASCAR from Aedes circumluteolus collected inside primary forest near the village of MAROVITSIKA. Serological studies in man using haemagglutination inhibition test have permitted to think that Wesselsbron virus have circulated quietly in MADAGASCAR. The detection of Wesselsbron antibodies in Lemurs sets the problem of the biological cycle.