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Open Access 01-12-2022 | Malaria | Study protocol

Evaluation of the protective efficacy of a spatial repellent to reduce malaria incidence in children in western Kenya compared to placebo: study protocol for a cluster-randomized double-blinded control trial (the AEGIS program)

Authors: Eric O. Ochomo, John E. Gimnig, Achuyt Bhattarai, Aaron M. Samuels, Simon Kariuki, George Okello, Bernard Abong’o, Eunice A. Ouma, Jackline Kosgei, Stephen Munga, Kiambo Njagi, Wycliffe Odongo, Fang Liu, John P. Grieco, Nicole L. Achee

Published in: Trials | Issue 1/2022

Abstract

Background

Spatial repellents are widely used for prevention of mosquito bites and evidence is building on their public health value, but their efficacy against malaria incidence has never been evaluated in Africa. To address this knowledge gap, a trial to evaluate the efficacy of Mosquito Shield™, a spatial repellent incorporating transfluthrin, was developed for implementation in Busia County, western Kenya where long-lasting insecticidal net coverage is high and baseline malaria transmission is moderate to high year-round.

Methods

This trial is designed as a cluster-randomized, placebo-controlled, double-blinded clinical trial. Sixty clusters will be randomly assigned in a 1:1 ratio to receive spatial repellent or placebo. A total of 6120 children aged ≥6 months to 10 years of age will be randomly selected from the study clusters, enrolled into an active cohort (baseline, cohort 1, and cohort 2), and sampled monthly to determine time to first infection by smear microscopy. Each cohort following the implementation of the intervention will be split into two groups, one to estimate direct effect of the spatial repellent and the other to estimate degree of diversion of mosquitoes and malaria transmission to unprotected persons. Malaria incidence in each cohort will be estimated and compared (primary indicator) to determine benefit of using a spatial repellent in a high, year-round malaria transmission setting. Mosquitoes will be collected monthly using CDC light traps to determine if there are entomological correlates of spatial repellent efficacy that may be useful for the evaluation of new spatial repellents. Quarterly human landing catches will assess behavioral effects of the intervention.

Discussion

Findings will serve as the first cluster-randomized controlled trial powered to detect spatial repellent efficacy to reduce malaria in sub-Saharan Africa where transmission rates are high, insecticide-treated nets are widely deployed, and mosquitoes are resistant to insecticides. Results will be submitted to the World Health Organization Vector Control Advisory Group for assessment of public health value towards an endorsement to recommend inclusion of spatial repellents in malaria control programs.

Trial registration

ClinicalTrials.govNCT04766879. Registered February 23, 2021.

Available only for authorised users

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Title: Evaluation of the protective efficacy of a spatial repellent to reduce malaria incidence in children in western Kenya compared to placebo: study protocol for a cluster-randomized double-blinded control trial (the AEGIS program)
Authors: Eric O. Ochomo
John E. Gimnig
Achuyt Bhattarai
Aaron M. Samuels
Simon Kariuki
George Okello
Bernard Abong’o
Eunice A. Ouma
Jackline Kosgei
Stephen Munga
Kiambo Njagi
Wycliffe Odongo
Fang Liu
John P. Grieco
Nicole L. Achee
Publication date: 01-12-2022
Publisher: BioMed Central
Keyword: Malaria
Published in: Trials / Issue 1/2022
Electronic ISSN: 1745-6215
DOI: https://doi.org/10.1186/s13063-022-06196-x

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Evaluation of the protective efficacy of a spatial repellent to reduce malaria incidence in children in western Kenya compared to placebo: study protocol for a cluster-randomized double-blinded control trial (the AEGIS program)

Abstract

Background

Methods

Discussion

Trial registration

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Abstract

Background

Methods

Discussion

Trial registration

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