Insecticide-treated bednets and curtains for preventing malaria

Abstract

Background: Malaria is an important cause of illness and death in many parts of the world, especially in Africa. There has been a renewed emphasis on preventive measures, both at community and at individual level. Insecticide treated bednets and curtains are a promising preventive measure.

Objectives: The objective of this review was to assess the effects of insecticide-treated bednets or curtains in preventing malaria

Search strategy: We searched the Cochrane Infectious Diseases Group trials register, Medline, Embase and the reference lists of articles. We handsearched journals, contacted researchers, funding agencies and net and insecticide manufacturers.

Selection criteria: Randomized and quasi-randomized trials of insecticide-treated bednets or curtains with a sufficient dose of a suitable insecticide compared with nets without insecticide or no nets at all. Studies including pregnant women were excluded.

Data collection and analysis: Trial quality was assessed and data extracted by the reviewer. Trial inclusions/exclusions were reviewed by two independent individuals.

Main results: Of 65 identified studies, 18 were included. Of these, 11 were randomized by cluster rather than individually. Mortality in children under five was measured in four trials. When impregnated nets were compared with plain nets or no nets, the summary relative risk was 0. 83. This translates to an estimate of protective efficacy of 17%. For treated nets compared with untreated nets, the relative risk of child mortality was 0.77. About six lives can be saved each year for every 1000 children protected with insecticide-treated nets. Insecticide-treated nets also reduced the incidence of mild malarial episodes by 48% (controls=no nets) and 34% (controls=untreated nets).

Reviewer's conclusions: Insecticide-treated nets appear to be effective in reducing childhood mortality and morbidity from malaria. Widespread access to insecticide-treated nets will require major financial, technical and operational inputs.