Mosquito Nets More Effective Against Malaria Than Thought
Apr. 03, 1996
WASHINGTON (AP) _ Looking for the most effective way to save the estimated million Africans who die each year from malaria, a $5 million study has come up with a simple answer: mosquito nets.
After extensive scientific tests in Africa of bednets soaked in insecticide, three international agencies concluded Wednesday that half the victims, particularly children under 5, could be saved each year if they sleep under nets.
The study itself saved thousands of lives, scientists said.
``We now have a firm basis for actually enhancing and promoting their use in Africa,'' said Tore Godal, head of the World Health Organization's Tropical Disease Research Program.
The tests were among the most complex and expensive ever conducted by international health authorities, involving 20 research institutions and donors and distribution of half a million nets.
The program, backed by the U.N. Development Program and the World Bank, conducted trial use of the nets in Kenya, where deaths were reduced by one-third in test communities, and in Ghana, where they went down by one-sixth, Godal said in an interview.
The Kenya trials also showed a 40 percent reduction in hospital admissions for severe malaria, scientists said.
``The really shocking thing is that these things, this simple technology can reduce mortality by so much,'' said Dr. Jacqueline Cattani, international malaria expert.
The challenge is to get the nets of life distributed on a continent where, unlike in Asia, they are neither widely manufactured nor sold.
Dr. Cattani said that as a result of the study and official interest in it, bednets could be more widely distributed in Africa by the end of the year. Only a handful of small companies manufacture mosquito nets in Africa, she said.
Results of the Kenya and Ghana trials were published in the April 5 issue of Tropical Medicine and International Health, a European journal. Other trails have been conducted in Gambia and Burkina Faso, with the Gambia results showing a 25 percent reduction and results being analyzed from Burkina Faso.
The cost of a repellant-soaked mosquito net is from $5.50 to $11 a person. Many poor African families already spend more than $65 a year trying to ward off malaria and keep mosquitoes out of their homes in other ways. Nighttime mosquito nets are widely used in Asia, but not in Africa, officials say.
The study's cost included mass distribution of the nets in randomly selected communities, as well as efforts to educate families in their use. Between 50,000 and 200,000 nets were given away at each site. Netless communities picked for comparison were promised nets at the end of the tests.
The advantage of mosquito nets over immunization programs, which have about the same per-person cost, is that they don't require doctors or nurses to distribute. The nighttime nets have proved effective, even though people may remain exposed all day long, Godal said.
``We do not quite understand why they work, but the most likely explanation is that they reduce the number of biters and the severity of illness is related to the number of bites,'' he said.