# Evaluation of the protective efficacy of a transfluthrin-based spatial repellent product to reduce malaria prevalence in Uganda: study protocol for a cluster-randomised double-blinded control trial—the Mossie-GO trial

## TL;DR

This study tests a new spatial repellent device (Mossie-GO™) to reduce malaria in Ugandan children under 5 by repelling mosquitoes in a double-blinded trial.

## Contribution

The study introduces a novel transfluthrin-based spatial repellent device and evaluates its efficacy in reducing malaria prevalence in a real-world setting.

## Key findings

- The trial will measure the protective efficacy of Mossie-GO™ in reducing malaria infection in children ≤5 years.
- Entomological transmission indicators and user acceptance of the device will be assessed.
- Results will inform malaria control strategies in rural and peri-urban Uganda.

## Abstract

Progress towards elimination and eventual eradication of malaria is threatened by challenges such as the rise in insecticide resistance and low coverage of existing vector control tools. Spatial repellents offer personal and household protection against biting mosquitoes by disseminating repellents into a given area. The trial described here aims to evaluate the efficacy of an active transfluthrin-based spatial repellent device (Mossie-GO™) against malaria in Uganda, using a placebo-controlled, double-blinded cluster randomised control trial. The study’s primary objective is to demonstrate and quantify the protective efficacy of Mossie-GO™ in reducing the prevalence of malaria infection in children ≤ 5 years of age. The study’s secondary objectives are to measure the impact of the intervention on entomological correlates of transmission, to determine user acceptance of the device and to quantify transfluthrin concentration in the air.

The trial has fifty-six clusters randomly assigned in a 1:1 ratio to either the intervention or placebo-control arm. One hundred children at baseline and sixty children ≤ 5 years of age will be sampled in each cluster at 6 and 12 months to measure the primary endpoint. Each child will be sampled from a different household to avoid within-house replication. A subset of households from each cluster will be selected for secondary endpoint sampling. All households enrolled into the study will be encouraged to continue use of other malaria control tools.

Trial results will contribute to the growing research on spatial repellent efficacy in sub-Saharan Africa and will inform recommendations for the use of spatial repellents in malaria control, specific to rural and peri-urban contexts in Uganda. Information on household characteristics, behaviour related to malaria exposure and user acceptability of the intervention will also be collected to improve understanding of the intervention usage and impact. Following the trial, results will be publicly disseminated.

The trial is registered with ClinicalTrials.gov 01/04/2024 unique identification (ID): NCT06232954.