Long ago in the Gambia, West Africa, a two-year-old boy named Ebrahim almost died of malaria. Decades later Dr. Ebrahim Samba is still reminded of the fact when he looks in a mirror. That is because his mother--;who had already buried several children by the time he got sick--;scored his face in a last-ditch effort to save his life. The boy not only survived but eventually became one of the most well-known leaders in Africa: Regional Director of the World Health Organization.

Needless to say, scarification is not what rescued Ebrahim Samba. The question is, What did? Was it the particular strain of parasite in his blood that day, his individual genetic or immunological makeup, his nutritional state? After centuries of fighting malaria--;and conquering it in much of the world--;it is amazing what we still do not know about the ancient scourge, including what determines life and death in severely ill children in its clutches. Despite such lingering questions, however, today we stand on the threshold of hope. Investigators are studying malaria survivors and tracking many other leads in efforts to develop vaccines. Most important, proven weapons--;principally, insecticide-treated bed nets, other antimosquito strategies, and new combination drugs featuring an ancient Chinese herb--;are moving to the front lines.