Entomological activities are essential to monitoring the impact of ITNs in Malawi where the primary vector, An. funestus, has been demonstrated to be resistant to most pyrethroid insecticides as well as to carbamate insecticides such as bendiocarb and propoxur. The Malawi NMCP malaria control strategy relies entirely on the distribution of insecticide-treated nets (ITNs) through mass campaigns at 3 year intervals and through routine distribution at ANC clinics. Given the high level of pyrethroid resistance, it is important to assess the impact of ITNs on malaria vector density, behavior and species composition as well as to continue to monitor the frequency and intensity of resistance of the local vectors to WHOPES recommended insecticides. Furthermore, novel ITNs are increasingly being implemented and as part of the recent 2016 mass campaign, Concern Universal (CU) distributed two PBO nets—PermaNet 3.0 and Olyset Plus—in parts of 4 districts in Malawi. Given the high levels of pyrethroid resistance and the fact that oxidase enzymes are a likely mechanism of resistance, this provides an opportunity to assess their impact on malaria vectors in Malawi.
The PMI AIRS Project will be working in Malawi in the coming months to conduct entomological monitoring and surveillance for resistance testing.