[Research on viral infections in South Pacific mosquitoes under natural conditions]

From 1975, epidemiological studies on arboviral diseases, conducted in New Caledonia, Vanuatu, Wallis and Horne Islands, have shown that 11 species of mosquitoes may harbour viruses in natural conditions. Virus isolations were attempted from 1,025 pools of Culicidae totalizing 32,182 individuals belonging to 5 genera and 21 species. Viral infections have been demonstrated in 76 pools (7.4%). The species harbouring viruses were: Aedes aegypti, Ae. alternans, Ae. notoscriptus, Ae. vexans, Ae. vigilax, Culex annulirostris, C. bitaeniorhynchus, C. iyengari, Culex pipiens quinquefasciatus, Coquillettidia xanthogaster. Among the strains definitively identified, dengue 1 virus was recovered from Ae. aegypti, Ae. polynesiensis, Ae. vigilax, dengue 4 virus was obtained from Ae. aegypti, Ae. vigilax, C. xanthogaster, C. annulirostris. Ross River virus was identified in Ae. vigilax and C. quinquefasciatus. The infected mosquitoes originated from New Cadedonia, Vanuatu (Aoba), Wallis and Horne Islands.