Integrated Malaria Vector Control with Microbial Larvicides and Insecticide-treated Nets in Western Kenya: a Controlled Trial

Overview

Journal Bull World Health Organ

Specialty Public Health

Date 2009 Sep 29

PMID 19784445

Citations 132

Authors

Ulrike Fillinger

Bryson Ndenga

Andrew Githeko

Steven W Lindsay

Affiliations

Soon will be listed here.

Abstract

Objective: To assess the contributions of both microbial larvicides and insecticide-treated nets (ITNs) in terms of reducing malaria incidence in an integrated vector management programme in an area moderately endemic for malaria in the western Kenyan highlands.

Methods: A pre-post, control group design was used. Larval and adult vector populations were surveyed weekly in six separate valley communities. The incidence of Plasmodium infections in children 6 months to 13 years of age was measured during the long and short rainy seasons each year. Baseline data were collected for 17 months, after which Bacillus-based larvicides were applied weekly to aquatic habitats in three of the valleys for another 19 months. At around the same time the larviciding was initiated, ITNs were introduced gradually into all study communities by the National Malaria Control Programme. The effect of larviciding, ITNs and other determinants of malaria risk was assessed by means of generalized estimating equations.

Findings: The risk of acquiring new parasite infections in children was substantially and independently reduced by ITN use (odds ratio, OR: 0.69; 95% confidence interval, CI: 0.48-0.99) and larvicide application (OR: 0.44; 95% CI: 0.23-0.82), after adjusting for confounders.

Conclusion: Vector control with microbial larvicides enhanced the malaria control achieved with ITNs alone. Anti-larval measures are a promising complement to ITN distribution in the economically important highland areas and similar transmission settings in Africa.

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