Bednets 11/8/04. By Caroline Cross Bednets treated with insecticide provide a physical barrier that helps prevent exposure to infected mosquito bites and reduces the number of mosquitoes in a room.

Most malaria carrying mosquitoes bite at night. Bednets treated with insecticide provide a physical barrier that helps prevent exposure to infected mosquito bites and reduces the number of mosquitoes in a room. It can reduce the lifespan of the mosquitoes that come into contact with it and thereby reduce the chance of malaria transmission.

Impregnated bednets reduce the morbidity and mortality from malaria in most areas tested, and reduce the number of cases of severe malaria in children under five years old. However, there are controversies surrounding the use of bednets. In high transmission areas where immunity develops over time, fewer infected bites may lead to delayed immunity and result in an increase in the number of cases of severe disease in older children.

Bednet use is encouraged in malarious regions, but nets can be relatively expensive and require regular re-treatment. In some areas, social marketing schemes are being encouraged to make nets available at an affordable price. Also, long-lasting insecticide treatments are being developed so that one treatment lasts the life-time of the net.