A previously undescribed mosquito densovirus was detected in colonies of Ae
des aegypti and Ae. albopictus from Thailand, using a polymerase chain reac
tion (PGR)-based assay, Phylogenetic analysis of this virus showed it to be
most closely related to ADNV isolated from Russian Ae. aegypti. Both Aedes
species were susceptible to oral infection with the Thai-strain virus. Lar
val mortality for Ae. albopictus was higher (82%) than for Ae. aegypti (51%
). Aedes aegypti were able to transmit the virus vertically to a high (58%)
proportion of G(1) progeny, and the virus was maintained persistently for
up to six generations. A PCR survey of adult Ae. aegypti and Ae. albopictus
in Thailand indicated that only Ae. aegypti are infected in the field, wit
h an overall prevalence of 44%. Densovirus infection in adult Ae. aegypti s
howed distinct seasonal variation. The Thai strain densovirus may play a ro
le in structuring Ae. albopictus and Ae. aegypti populations in nature.