The Effect of Commonly Available Spraying Synthetic Insecticides on Indoor Malaria Vector Control

Abstract

Malaria affects millions of people in Nigeria. Despite progress made in recent years, it continues to pose a major threat to life in low-resource settings like Ifite community Awka, south east Nigeria. One of the key strategies employed in malaria control programs is Indoor Residual Spraying (IRS), a targeted intervention aimed at reducing malaria transmission by focusing on the female Anopheles mosquitoes that vector Plasmodia species. Indoor biting and resting mosquitoes were sampled in students’ room by pyrethrum knockdown collection method with commonly available pyrethrum insecticide. Knocked-down mosquitoes were identified based on appearance of head, thorax, wing colours, and tarsal segments of hind legs. Engorgement status was determined by observing abdomen of knocked-down mosquitoes. In-door resting density (IRD) was estimated using the ‘number of female mosquitoes collected per room per night’ while man-biting rate (MBR) was the ‘total number of engorged females divided by number of room-occupants the night before collection’. All knocked-down mosquitoes were Anopheles species of which a 66.7% were engorged. Estimated IRD was 12 mosquitoes per room per night while MBR was of 4 bites per man per night. This result demonstrated the effectiveness of IRS with pyrethrums in knocking down Anopheles mosquito, and thus capable of disrupting malaria transmission cycle in the study area.  However, future research should focus on development of eco-friendly bio-pesticides which formulation and application techniques can allow for feasible monitoring and evaluation of malaria vector management.