Surveillance of dengue vector at thiruvananthapuram (Kerala) International Airport

A survey of Aedes (Stegomyia) mosquitoes was undertaken in and around the International airport at Thiruvananthapuram during premonsoon season. An attempt has been made in this paper to elaborate on the presence of risk potential for Dengue /yellow fever at the airport with the detection of Aedes breeding. The entomological indices have also been discussed with regard to presence of potential wet containers and rate of infestation by Aedes mosquitoes. The airport area was searched for Aedes (Stegomyia) breeding where 20% of the premises were found positive for Aedes aegypti breeding and one premise (6.6%) was found positive with Aedes albopictus breeding. In the 400 meters (perimeter) of airport, four municipal wards namely Chakka, Sankumugam, Valiyathura and Vettucadu were surveyed. The house index ranged from 5.8% to 11.7% for Aedes aegypti while, it was between 9.8% to 19.2% with regard to Aedes albopictus. The container index ranged between 4.4% to 9.9% for Aedes aegypti and 7.1% to 15.3% for Aedes albopictus. Breteau index was found to be between 23.5% to 51.9% for both the species. The susceptibility test conducted against different insecticides showed that the immature stages of Ae. aegypti and Ae. albopictus were found to be susceptible to the commonly used larvicides in public health viz. Temephos (0.02 ppm), Fenthion (0.05 ppm), Malathion (1.0 ppm) and Fenitrothion (0.06 ppm).