[Control of malaria using mosquito nets impregnated with pyrethroids in Burkina Faso]

An experimental trial of malaria control was carried out in the village of Karangasso in the south-west Burkina Faso. It was based on the use by the whole population of deltamethrin impregnated bed nets at 25 mg/m2. During the first year pretreatment data on entomology, parasitology and pathological incidence of malaria were collected in the whole village. During the second year a quarter of the village with a population of 1,200 was chosen for the experiment and impregnated bed nets were given to everybody while the other quarter of the same population size was kept as a control area. Malaria transmission was reduced by 82% due to the decrease of both vector populations and sporozoitic indexes. It should be pointed out that this reduction in transmission was evaluated on non-protected catchers and consequently was underestimated for the villagers sleeping under nets. Parasitic index remained about the same but the mean parasitic load decreased significantly. Pathological incidence, based on the number of clinical malaria cases confirmed by blood examination, decreased by 59%. This trial shows that mass use of deltamethrin impregnated bed nets should be considered as a valuable tool for malaria control. The purchase of bed net is expensive but could be reduced sharply. The cost of the impregnation is very low regarding the residual effect which remains one year. The acceptance by the population was good.