Stegomyia indices of Aedes mosquito infestation and container productivity in Alappuzha district Kerala

摘要

The aim of the present study is to find out the seasonal variation in container productivity and infestationlevels by Aedes albopictus skuse and Aedes aegypti Linnaeus in Alappuzha district. In total, 1010 housesand 3770 water-holding containers were inspected during both the dry and wet period surveys, and 1606pupae were collected and all those immature were identified as Ae. albopictus. The maximum Breteauand Pupae index was found to be 89.22% and 395% during the month of July. The overall indices werehigher in the wet than dry season. Discardable containers were important that had the highest prevalenceof Ae. albopictus larvae during both the dry and wet periods. Non-discardable containers were importantcontributors to larval production during the dry period (40%) compared with the wet period (18%). Mostof the larval habitats observed in both wet and dry season were small tin and plastic waste containerspositive for Ae. albopictus larvae. Non-discardable containers were more important contributors for pupalproduction during the dry period (60%) whereas discardable containers were important pupae producersduring wet period (51%). Large and open shape containers produced 71% of total pupae especiallyplastic sheet. A total of 2514 (146 pools) mosquitoes were screened for dengue and chikungunya virus byRT-PCR. However, there was no detection of dengue and chikungunya virus genomic RNA. Generally,Ae. aegypti, (L.) is considered as the primary vector for the spread of dengue and chikungunya virusworldwide. However, our present entomological investigations revealed only the presence of Ae.albopictus. So we believe that in Alappuzha district Ae. albopictus is the vector for the disease burden ofdengue and chikungunya virus.