The use of permethrin-impregnated wall cloth (Mbu cloth) for control of vectors of malaria and leishmaniases in Kenya — I. Effect on mosquito populations

The impact of a new design of permethrin-impregnated wall cloth (“Mbu” (mosquito) cloth) on mosquito populations was assessed in Marigat area of Baringo District, Kenya. The cloth was fitted in 2000 houses. Mosquito relative density, species composition and the proportion of blood-fed females before and during the use of the Mbu cloth were monitored by hand catch, exit trap and CDC light trap catches. The common mosquito species were Culex quinquefasciatus, Mansonia uniformis, Anopheles gambiae sensu lato and An. funestus. A statistically significant decline in the mosquito population was observed following the introduction of the cloth. The decline was particularly high during the first and second six month impregnation cycles when it ranged between 43 and 94% indoors. C. quinquefasciatus was less affected by the cloth than other species, while M. uniformis apparently avoided treated houses. An. gambiae s.l. and An. funestus were collected in extremely low numbers during the post-treatment period. The Mbu cloth and other permethrin impregnated wall-hanging fabrics constitute a novel way of controlling mosquitoes and malaria in rural communities.