Indoor Residual Spraying

A malaria vector control practice in which a residual insecticide is applied to the internal walls and ceilings of housing structures where malaria-carrying mosquitoes rest. The World Health Organization names it as one of the two core vector control interventions alongside insecticide-treated nets, and currently recommends deploying one or the other in most areas at risk of malaria. Mosquitoes contact the insecticide when they rest on treated surfaces, so the practice can rapidly reduce malaria transmission. Residual insecticides date from the development of DDT in the early 1940s, and spraying campaigns formed the backbone of the WHO Global Malaria Eradication Programme of 1955 to 1969.