Transmission of Venezuelan equine encephalomyelitis virus by Aedes sollicitans and Aedes taeniorhynchus (Diptera: Culicidae).

Experimental studies compared the vector competence of Aedes sollicitans (Skuse) and Ae. taeniorhynchus (Wiedemann) collected on Assateague Island, Va., for an epizootic strain (Trinidad donkey) of Venezuelan equine encephalomyelitis (VEE) virus. Infection rates were significantly higher in Ae. sollicitans (101/107, 94%) than in Ae. taeniorhynchus (103/175, 59%), even though both species fed concurrently on the same infected hamsters. Similarly, dissemination and transmission rates were significantly higher in the Ae. sollicitans population tested. Although both Ae. taeniorhynchus and Ae. sollicitans are natural vectors of VEE virus, the latter species should be considered a more efficient vector of VEE epizootic strains, based on its greater susceptibility to infection and higher transmission rates.