Indoor Residual House Spraying: A Most Effective Way of Malaria Transmission Control

In Southern Africa, malaria kills more people between January and April each year than during other periods of the year.  This is because there are more abundant water collections for mosquito breeding between January and April.  Spraying dwellings with an effective and persistent insecticide before this peak period of malaria transmission will reduce the population of malaria carrying mosquitoes that enter houses during the night to feed on blood of sleeping occupants, thus controlling malaria transmission and preventing malaria-related illness and deaths.

Residual house spraying relies on the fact that the most malaria carrying mosquitoes enter houses during the night to feed on the occupants and rest on the walls or roofs prior to and/or after feeding and it the wall or roof is treated with an effective residual insecticide such as DDT, Icon, Deltamethrin, Fendona, Syfluthrin etc, the mosquito will pick up a lethal dose as it rests on treated surfaces.

In Southern Africa high transmission takes place between January and May.  To ensure people's protection against malaria infection by indoor residual house spraying, all houses within the areas to be protected should be sprayed before the start of the transmission season, that is, before January each year.

Actions For National Malaria Control Programmes:

	Mobilise, inform and educate the community on the need for indoor residual spraying for their collaboration and cooperation.
	Spray and achieve required coverage before the transmission season
	Supervise and monitor spraying operations to ensure quality, timeliness and judicious use of insecticide
	Soon after the malaria season, procure and deliver required commodities and logistics for the following malaria season

Action By The Public

	Prepare the houses the day there are to be sprayed to ensure complete coverage of sprayable surfaces
	Do not wash or replaster sprayed walls for atleast six months post application
	People should stay/sleep indoors during the main biting period of the mosquitoes

Malaria control is possible.  The Indoor residual spraying of dwellings has been a very successful strategy for controlling malaria in Southern Africa

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