Vector control operations in the African context.

In order to define the scope of vector control as a component of malaria control in the WHO African Region, examples of recent experiences with different vector control methods in this region are reviewed. Residual house spraying applied alone or in combination with mass drug administration has failed to interrupt malaria transmission in savanna areas for several technical and administrative reasons. Nevertheless, there is evidence that residual house spraying has led to an improvement in general health. However, the existence of DDT and dieldrin/HCH and lately malathion resistance in the Sudan in Anopheles gambiae s.l. would militate against the use of residual house spraying as a main tool for long-term malaria control. It should therefore be used only to reduce malaria prevalence to an acceptable level until integrated control methods can be developed and become operational.Experience with larval control, space spraying, and biological control of vectors is also reviewed, and the value of self-help methods of reducing man-vector contact under African conditions is examined. All these methods need to be more thoroughly assessed. Several proposals are made for applied field research.