LLIN Evaluation in Uganda Project (LLINEUP3)

Overview

In Uganda, the National Malaria Control Division (NMCD) and implementing partners are planning to deliver long-lasting insecticidal nets (LLINs) nationwide, through a mass distribution campaign in 2023. LLINs will be distributed free-of-charge to all Ugandan households, aiming to achieve universal coverage. LLINs treated with a pyrethroid insecticide plus chlorfenapyr (PermaNet Dual, Vestergaard) and LLINs treated with a pyrethroid insecticide plus PBO (PermaNet 3.0, Vestergaard) will be distributed as part of this distribution campaign, presenting an opportunity to rigorously evaluate and compare these two LLINs at scale across Uganda. In collaboration with the MOH, this cluster-randomised trial will compare the impact of LLINs combining chlorfenapyr with a pyrethroid to LLINs combining PBO with a pyrethroid into Uganda's 2023 LLIN distribution campaign, as was done successfully at the time of the last LLIN distribution campaign conducted in 2020-21. A major strength of this trial is the use of malaria incidence as the primary outcome measure. Incidence of malaria, defined as the number of symptomatic cases of malaria occurring in a population at risk over time, is the gold standard for assessing malaria burden. However, cluster-randomised trials using malaria incidence as the primary outcome typically involve study cohorts and are very expensive and logistically challenging. The novel approach for measuring malaria incidence is to utilize data collected routinely at health facilities. By defining target areas around health facilities and collecting data on the location of residence of patients diagnosed with malaria, this study will be able to generate longitudinal measures of malaria incidence at an unprecedented scale across Uganda as done in the LLINEUP2 trial (NCT04566510). These results will inform policies and programmes for malaria and potentially provide evidence to support widescale deployment of dual AI chlorfenapyr-pyrethroid LLINs. This study, the first evaluating PermaNet Dual LLINs, will also provide evidence for a second in class chlorfenapyr net, a potential tool to be added to the malaria control tool kit.

This is a cluster-randomised trial to evaluate the impact of long-lasting insecticidal nets (LLINs) distributed in Uganda through the 2023 national universal coverage campaign. A cluster has been defined as the target area surrounding an MRC. A total of 24 clusters will be included in the study, covering 20 moderate-high malaria burden districts in Uganda. Clusters have been randomised in a 1:1 ratio to receive one of two types of LLINs: (1) chlorfenapyr-pyrethroid LLINs (PermaNet Dual, n=12) or (2) PBO-pyrethroid LLINs (PermaNet 3.0, n=12). The intervention, including delivery of the LLINs and social and behaviour change communication (SBCC), will be led by the Ugandan NMCD and other stakeholders. Currently, LLINs are scheduled to be distributed in the study areas during waves 5 and 6 from September to October 2023 as part of the national LLIN distribution campaign. The evaluation of the intervention will include: 1) health facility surveillance at the participating MRCs to generate continuous estimates of malaria incidence for each MRC target area; 2) cross-sectional community surveys at 12- and 24-months post-LLIN distribution to gather information on parasite prevalence, anaemia prevalence, net ownership, coverage, and use, 3) entomology surveys at 12 and 24 months to gather information on vector density. The primary outcome of the trial will be malaria incidence as estimated using the health facility surveillance.