The World Health Organisation on Thursday recommended that malaria endemic countries widely distribute free insecticide-treated mosquito nets that give long-term protection against the disease which kills more than one million people a year.
The new guidance from the United Nations agency follows "impressive results" in Kenya, where mortality was reduced by 44 percent among children sleeping under long-lasting nets that cost $5.
"For the first time, WHO recommends that insecticidal nets be long-lasting and distributed either free or highly subsidised and used by all community members," it said in a statement.
Free mass distribution of the nets, which are efficient for at least three years and also kill the mosquitoes, is a "powerful way to quickly and dramatically increase coverage, particularly among the poorest people".
Malaria kills a child every 30 seconds, mainly African children under 5 years old, WHO says. Some 114 countries in Africa, Asia and Latin America are endemic.
The disease, which makes more than 500 million people a year severely ill, is caused by a parasite transmitted via bites from infected mosquitoes.
Conventional nets need to be re-treated regularly and many people fail to wash them properly or replace them when torn.
WHO director-general Margaret Chan said the new guidance provided "a road map for ensuring that life-saving long-lasting insecticidal nets are more widely available".
"Long-lasting insecticidal nets, with longer useful life, are cheaper to use, even if they are more expensive to buy," the WHO said in a paper sent to its 193 member states.
WHO's previous guidelines recommended providing insecticide-treated mosquito nets for use by children under five and pregnant women.
"However, recent studies have shown that by expanding the use of these nets to all people in targeted areas, increased coverage and enhanced protection of vulnerable groups can be achieved while protecting all community members," it said.
In Kenya, between 2004 and 2006, a near tenfold increase in the number of children sleeping under insecticide-treated nets resulted in 44 percent fewer deaths than among children not protected by nets, according to preliminary government data.
President Mwai Kibaki last year launched an effort to distribute 3.4 million long-lasting insecticidal nets free of charge to children in 45 of Kenya's 70 districts, the WHO said.
"Seven lives were saved for every 1,000 nets given out," Peter Olumese, a medical officer with WHO's Global Malaria Programme, told Reuters on Thursday.