About half of all Ghanaian households now buy something for mosquito control. From 15 to 35 percent of households might invest in nets during the first year of a campaign, researchers found. In some endemic areas, children are bitten by several malaria- transmitting mosquitoes each night, LeSar said. In a study of five regions of Gambia that had a total population of 116,000 people, use of impregnated nets reduced mortality in children aged 1 to 9 by 25 percent. Other, more targeted programs have produced mortality reductions of up to 60 percent.
Cost is a barrier in some places.
In one study, frequent washing of nets soiled by children shortened the repellent action significantly. In addition, insecticide-resistant mosquitoes have been found. Use of nets, however, is less likely to promote resistance than the spraying of chemicals whose main purpose is to kill, rather than repel, mosquitoes.