The Stegomyia survey and susceptibility status of Aedes aegypti to insecticides in Calcutta seaport area
Biswas, S.; Kumar, K.; Singh, K.
Journal of Communicable Diseases 20(3): 253-259
1988
ISSN/ISBN: 0019-5138 PMID: 3256570 Document Number: 310710
In view of WHO revised regulations of 1969 requiring effective Stegomyia control in all international port areas, a survey of A. aegypti was conducted in the Calcutta seaport area in September 1983. Results are compared with those of a similar survey in 1978. Despite previous findings suggesting that aedine populations would be on the wane in the month of September, A. aegypti indices in the port area were above (mostly, very much above) the 1% limit permissible under International Health Regulations. A slight reduction was apparent in the 1983 compared with the 1978 figures, probably due to seasonal factors. A. albopictus was also widely present. Total breakdown of anti-mosquito work is attributed to derelict hulks littering the harbour shorelines where they gathered rainwater, together with constant movements of country crafts and barges which showed high A. aegypti breeding, and complete lack of anti-mosquito measures in the vessels berthed in the docks and jetties. Insecticide susceptibility tests on field-collected 3rd- and 4th-instar larvae of A. aegypti indicated high resistance to DDT and HCH/dieldrin but susceptibility to fenthion, fenitrothion, malathion and temephos.