Enlarge Image Blood tied. The malaria parasite P. falciparum, which is carried by the Anopheles mosquito (pictured in their larval stage), can't infect red blood cells without a particular protein. Credit: Wellcome Trust Sanger Institute The most dangerous malaria parasite, Plasmodium falciparum, is an unusually versatile bug. The single-celled safecracker carries a wide collection of protein "keys" that it can use to jimmy receptor "locks" on the surface of red blood cells, tricking the cells into letting it in. Block one of these entry points with a drug, and the parasite just uses a different key. But now, researchers...
