ATLANTA -- The quest for the world's first malaria vaccine appears to have taken a big step: A study in Africa shows experimental shots cut the risk of disease in children by half.

The initial results from a final stage of testing were released yesterday, and GlaxoSmithKlein, developers of the vaccine, called it a milestone.

The vaccine won't be available for at least three years, however, as crucial further testing must be completed. Then it must be reviewed by government agencies in Europe and in individual African countries.

The early results show the vaccine is about 50 percent effective, significantly lower than the protection in more common vaccines. But some said it's a vast improvement and could save hundreds of thousands of lives.

Public health efforts have concentrated on malaria drugs and other ways to prevent infection such as mosquito bed netting and insecticides.

Early results, released yesterday at a malaria conference in Seattle, were published in the New England Journal of Medicine. -- AP

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