Malaria is a disease caused by a parasite that lives part of its life in humans and part in mosquitoes. Malaria remains one of the major killers of humans worldwide, threatening the lives of more than one-third of the world's population. It thrives in the tropical areas of Asia, Africa, and Central and South America, where it strikes millions of people. In the early 1970's, a mysterious clustering of arthritis cases occurred among children in Lyme, Connecticut, and surrounding towns. While scientists were busy describing signs and symptoms of Lyme disease to help doctors diagnose patients,...