Impact of interventions on mosquitoes resting behaviour and species composition in Lugeye village in Magu district, Northwestern Tanzania

Abstract

Background: Understanding the impact of intervention tools on vector behaviour, host preference, resting, and infectivity rates is paramount in malaria control planning. Magu district was one of the districts in lake zone regions in northwestern Tanzania covered with indoor residual spray and long-lasting insecticidal nets in the main malaria control campaign. After interventions, this study evaluated the mosquito's host preference and resting behaviour in Lugeye village in rainy and dry seasons.

Methods: Mosquitoes were collected both indoors and outdoors using the rest pots. The collection was done in both rainy and dry seasons. The samples were collected bi-weekly for three months each season.

Results: A total of 254 mosquitoes were collected in both dry and rainy seasons, indoors and outdoors. The most abundant species were Anopheles funestus s.s. and An.arabiensis. Most blood meals from bovines rested outdoors, while human blood meal sources rested outdoors. Sporozoite-positive mosquitoes were found only during the dry season.

Conclusion: This study's findings have shown that implementing IRS and LLIN interventions has led to a species shift from An.gambiae s.s. to An.funestus and An.arabiensis. The inclusion of vector insecticide resistance information can be of paramount importance in appropriate intervention tool selection.