Redesign your house to stop malaria

28 May 2009

Paul Chinnock

Source: Malaria Journal (see original article)

Comments

The eaves of this house have been closed off and a ceiling has
been created with papyrus to reduce mosquito entry. (From the
article by Harrysone Atieli et al.)

Insecticide-treated bednets (ITNs) now play a big part in malaria control programmes. They have been shown to be effective in protecting those who sleep under them from mosquito bites and to reduce the incidence of malaria. But during the hours that mosquitoes are out and about adults, in particular, do not spend all their time in bed. Researchers in Kenya, working in a rural area in the west of the country, have been looking at ways of reducing the number of mosquitoes entering the house itself.

In small randomised controlled trial with ten houses in each arm, Harrysone Atieli and colleagues compared traditional, unmodified village homes with houses that had been modified by the addition of papyrus ceilings, closure of open eaves, and fixing of insecticide-impregnated netting above sleeping rooms. Local community members and women’s groups were asked to weave the ceilings from papyrus reeds.

The researchers used a recognised technique (the pyrethrum spray method) to determine the densities of mosquitoes resting in the houses. Each house was sampled a total of eight times over a period of four months. Atieli et al. also conducted interviews with the villagers to find out their opinions of the house modifications.

Around 80% fewer Anopheles mosquitoes entered the modified homes compared with control houses. The reductions were statistically significant.

The researchers report the important finding that, “Unlike previous studies in which different ceiling materials were used, our modification did not reduce air flow or make rooms feel stuffy”. The villagers also commented favourably on the home modifications.

Atieli et al. point out that poor housing has long been known to lead to poor health. Indeed there have been studies showing an association between malaria incidence and type of house construction. Nevertheless, insufficient attention has been paid to finding simple, effective ways to improve the design of houses.

No data on the incidence of malaria was collected in the Atieli study. However, the encouraging outcome, in terms of the reduction of mosquito numbers, may inspire further research, either focusing on malaria or on the more general issue of home improvements for better health.

Reference

1. Atieli HE, Menya D, Githeko A, Scott T (2009). House design modifications reduce indoor resting malaria vector densities in rice irrigation scheme area in western Kenya. Malar J;19;8(1):108. Available from: www.ncbi.nlm.nih.gov/pubmed/19454025