Kere and colleagues were able to demonstrate significant reductions in the incidence of malaria (Plasmodium falciparum) in children under the age of 10 years with the use of permethrin impregnated bednets. Eight hundred and sixty (860) people in 23 villages were given impregnated bednets and were compared with 520 people in 20 villages from a contiguous area who served as a control population. Incidences were based on mass blood screenings with thick and thin blood films examined conventionally.
Greater nighttime outdoor exposure of adults resulted in less impressive improvements than in children, who were more likely to be under the bednet during peak mosquito biting time.
In addition to reductions in malarial incidence in children, febrile episodes in children were reduced in frequency as well as the number of Anopheles farauti mosquitoes themselves. Survival of trapped mosquitoes was shown to be significantly reduced in the bednet homes compared with the control area, leading to the authors' conclusions that the nets not only protect people, but kill mosquitoes as well. Protection by the nets continued to be satisfactory for up to 1 year after permethrin treatment.