Studies on the prevalence of Aedes aegypti in South  Andaman

Information on the prevalence of Aedes aegypti was lacking. Hence, a pilot survey was carried to assess the prevalence, distribution of Ae. aegypti, in South Andaman.

In all 195 premises were searched from 8 localities of South Andaman district for Ae. aegypti. All the localities were found positive for Ae. aegypti. The Breteaux index was higher than the container index. Overall, Breteaux index was three times more than that of container index. The container index ranged between 8.16 (Guptapara) and 18.8 (Wandoor). The adult house index was 0 in six of the villages surveyed except in Guptapara and Sipighat, where the indices were 13.9 and 19.0 respectively (table 3.14).

The number of containers examined with water were 573 with an average of 2.9 per premise. Significant high container indices of Ae. aegypti were recorded during the survey in both outdoor and indoor habitats. Metal containers were the highest among the positive containers for Ae. aegypti followed by mud/brick/cement containers and plastic containers.

Among the water storage containers examined, Ae. aegypti breeding was detected in 6% of the containers of potable water and 20% in non-potable water. There was a significant difference between the proportions of the Ae. aegypti breeding containers situate indoors or outdoors.

The results of the survey suggests that Ae. aegypti is infiltrating and gaining a foothold the rural areas of South Andaman. Thus the suburban areas around Port Blair are also receptive to Dengue virus.