Entomological investigations on malaria vectors in some war-torn areas in the Trincomalee district of Sri lanka after settlement of 30-year civil disturbance

Abstract

Background. Malaria was an endemic problem in Trincomalee District, Eastern Province of Sri Lanka. Very few recent data concerning Anopheles are available which transmit malaria. Therefore, the aim of this study is to identify various Anopheles species and the dynamics of anophelines including malaria vectors in Trincomalee District for effective vector control under the current malaria elimination program embarked in the country. Method. Entomological surveys were conducted on a monthly basis, using five entomological techniques, namely, indoor hand collection (HC), window trap collection (WTC), cattle-baited net collection (CBNC), and cattle-baited hut collection (CBHC) from June 2010 to June 2012 in 32 study areas under five entomological sentinel sites. Results. Seventeen anopheline species were encountered, of which Anopheles subpictus was the predominant species in all sampling methods. It is noted that A. culicifacies and A. subpictus have adapted to breed in polluted water in urban settings which may cause serious implications on the epidemiology of malaria in the country. Conclusions. It is important to determine the abundance, biology, distribution, and relationship with climatic factors of main and secondary malaria vectors in Sri Lanka in order to initiate evidence based controlling programs under the current malaria elimination program in Sri Lanka.