Density patterns of anophelines and their relation to malaria in Bastar district, Madhya Pradesh

Abstract

Density patterns of 17 species of anopheline mosquitoes collected between 1980 and 1981 from indoor and outdoor resting places of a highly malarious area of Bastar district, Madhya Pradesh are given. A. culicifacies and A. fluviatilis are the important vector species in the region. The former was highly endophilic and found throughout the year and its man hour density (MHD) ranged from 7.6 to 78 with peaks in February and July. The latter was highly exophilic, also found throughout the year. Its density ranged from 1.6 to 7.0 per 10 man hours with a peak in July/August. A. subpictus was considered as potential vector species, found throughout the year and was endophilic, having MHD ranging from 0.9 to 148 with peaks in February-March and July-August. The MHD variations of other species were; A. aconitus (0.02-1.04), A. annularis (0.02-10.4), A. barbirostris (0.04-1.07), A. hyrcanus (1.30-1.86), A. jamesii (0.01-0.46), A. jeyporiensis (0.01-1.06), A. karwari (0.01-0.04), A. maculatus (0.01-0.03), A. pallidus (0.02-2.4), A. splendidus (0.02-0.32), A. tessellatus (0.02-0.12), A. theobaldi (0.01-0.03), A. vagus (0.01-2.3) and A. varuna (0.03-0.31). Results of gut and gland dissections showed correlation of infection with the occurrence of peak vector densities. The density levels and seasonal activities of vectors as well as potential vector species are favourable for perennial transmission of malaria in Bastar district.