Multiple dengue virus types harbored by individual mosquitoes

The existing knowledge on pathogenesis and aetiology of DHF establishes that Dengue Hemorrhagic Fever (DHF) and Dengue Shock Syndrome (DSS) are caused by two subsequent infections of two different serotypes of dengue affecting a common human population with a time gap. Present studies have been undertaken on 212 laboratory reared infected individual mosquitoes from larvae collected from 31 dengue endemic towns of Rajasthan, India. Type specific DEN viruses were detected from individual mosquitoes employing RT-PCR. In 78.7% of 212 infected individual mosquitoes studied, vertically transmitted multiple DENV types were observed. We report for the first time that single mosquitoes contain multiple dengue virus types.