<<Print>>

Mosquitoes can rapidly develop resistance to bed nets treated with insecticide, a new study from Senegal suggests. In recent years the nets have become a leading method of preventing malaria, especially in Africa. The researchers also suggest the nets reduced the immunity of older children and adults to malaria infection. But other experts say the study was too small to draw conclusions about the long-term effectiveness of nets. In the war against malaria, the cheapest and most effective weapon to date has been the long-lasting insecticide-treated bed net. Over the last few years the nets have been widely distributed in Africa and elsewhere - the World Health Organization says that when properly deployed they can cut malaria rates by half. In Senegal, around six million nets have been distributed over the last five years. In this study researchers looked at one small village in the country and tracked the incidence of malaria both before and after the introduction of nets in 2008.