Survival and replication of dengue-2 virus in diapausing eggs of Aedes albopictus (Diptera: Culicidae).

Survival and replication of dengue-2 virus (family Flaviviridae, genus Flavivirus, DENV-2) was determined in diapausing eggs of Aedes albopictus (Skuse) (Diptera: Culicidae) to evaluate the importance of this mechanism for viral maintenance during adverse climatic conditions. Infected and uninfected eggs of Ae. albopictus were induced to diapause under low temperature and short photoperiod. Virus was detected by reverse transcription-polymerase chain reaction and isolated in C6/36 cells from both diapausing eggs and nondiapausing eggs. Nucleic acid hybridization was used to monitor viral replication in diapausing eggs. DENV-2 might survive in infected diapausing eggs in a relatively quiescent status based on the absence of areplicative intermediate RNA. In contrast, the viral replicative intermediate RNA along with the replicative form RNA was detected in nondiapausing eggs. It seemed that the virus replicated more actively in nondiapausing eggs than in diapausing eggs. Infected diapausing eggs may play an important role in the maintenance of DENV during adverse climatic conditions in nature.