Preliminary evaluation of insecticide-impregnated ceiling nets with coarse mesh size as a barrier against the invasion of malaria vectors.

We evaluated the effectiveness of installing the Olyset® Net on the ceiling in preventing the invasion of malaria vectors. This study was conducted in houses in western Kenya. The number of resting mosquitoes inside the houses reduced when the ceiling and eaves of the houses were covered with the net. The mosquito densities remained low for 9 months, until the nets were removed.