Insecticide treated eave nets and window screens for malaria control in Chalinze district, Tanzania: a study protocol for a household randomized control trial

Abstract Background: Long-Lasting Insecticidal nets (LLINs) have contributed to the reduction of malaria in sub-Saharan Africa, including Tanzania. However, they rely on daily user behaviour and high coverage which is difficult to maintain. Also, insecticide resistance among malaria vector mosquitoes is contributing to reduced efficacy of control tools. To overcome these problems, we propose to evaluate a new tool for house modification, the dual active ingredient (dual AI) insecticide treated eave nets (ITENs) in combination with insecticide treated window screens (ITWS) for the control of malaria. Methods: Four hundred and fifty (450) households with intact walls, open eaves without screens or nets on the windows in Chalinze district will be eligible and recruited upon written informed consent. The households will be randomly allocated into two arms: one with ITENs and ITWS installed and the other without. Malaria parasite detection using a quantitative Polymerase Chain Reaction (qPCR) will be conducted shortly after the long rain (June/July, 2022) as the primary outcome and shortly after the short rain (January/February, 2022) as the secondary outcome. Other secondary outcomes include clinical malaria cases, and density of malaria vectors and nuisance after the short rain and long rain. In addition, surveys will be conducted in households with ITENs and ITWS to estimate the intervention’s cost during installation, adverse effects after one month of installation, and presence, fabric integrity and user acceptance after six and twelve months of installation. Bioefficacy and chemical content will be evaluated after 12 months of installation. Discussion: ITENs and ITWS have been shown in Kenya to reduce indoor mosquito density. However, it was not known if the indoor mosquito density reduction translated into reduction of malaria cases. Data from the study will measure the public health value of an additional intervention for malaria control in areas of mosquito insecticide resistance that does not require daily adherence. Trial registration: The study is registered on ClinicalTrials.gov.