Arbovirus studies in southwestern Venezuela during 1973-1981. II. Isolations and further studies of Venezuelan and eastern equine encephalitis, Una, Itaqui, and Moju viruses.

Increasing utilization of arable land in southwestern Venezuela has led to a potential increase in human exposure to arbovirus infections. Since previous studies in the Catatumbo region of this area documented the presence of eastern equine encephalitis (EEE) and Venezuelan equine encephalitis (VEE) viruses, an attempt was made to study the transmission and maintenance of these viruses from 1973 to 1981. Isolations of EEE, VEE ID strains, Una, Itaqui , and Moju viruses were repeatedly obtained from mosquitoes, mostly Culex ( Melanoconion ) spp. and sentinel hamsters. The results indicate that these viruses constitute a potential hazard to public health in the area. Further, the strategic location of the Catatumbo region, between enzootic tropical foci of arboviruses, may provide circumstances and conditions for study of both enzootic maintenance and movement of these viruses.