Attempts to Transmit Chikungunya Virus with Six Species of Mosquito1

Females of Culex univittatus, Culex poicilipes, Aedes circumluteolus, Aedes calceatus, Aedes simpsoni and Aedes aegypti, originating from populations in southern Africa, were tested for infection rates and ability to transmit chikungunya virus between vervet monkeys, Cercopithecus aethiops. The first species failed to transmit the virus and, with the exception of Ae. simpsoni, infection rates were low. With Ae. aegypti 3.0 logs of virus failed to infect whereas at 5.3 logs 74–92% were infected. After 21 days the transmission rate with this species was 78% and after 49 days 12%. Despite the lower transmission rate there was no definite evidence that the level of virus in the mosquito had decreased at the latter time.