Studies on some aspects related to vectorial status of anopeline species in the transnission of human malaria at Ampagala Ruwanwella health area in Sri Lanka

Abstract

The vectorial status of anopheline species prevalent at Ampagala in the wet zone of Sri Lanka, where an epidemic outbreak of Pla.smQdJ~umY~va.x occured, was investigated. The study was carried out during June to December 1983. The resul ts showed the presence of thirteen (13) species of anophe1ines (Ag.aconitus, !!!.annularis, !!!. barbirostris, An.culicifacies, , Ag..iamesi, !a.karwari, !a.maculatus, :W,.nigerrimus, :W,.pal 1idus , An.subpictus, !g. tesselatus, An.vagus and An.yaruna) showing monthly variations in prevalence. All these species showed some attraction to llUk~.!a.culicif~cies and!a.subpictus were found resting indoori. Four (4) species Aa.culicifacies, !r!.~, !!2..iamesi and !a.,karwari were found infected with Plasmodia. The ob~ervation seem to suggest !a.-culicifacies the already known vecto!.', to be the most efficient species in the transmission of human malaria in the area. Most of the other species specially those found wi~h natural infections of .PlasID6dia may be playing some role in transmission, particularly when present in high deDSities and in the presence of high parasite carriers. Therefore most of the species of anophe1ines in the area could be potential vectors of human malaria.