Six years after the genome of the most deadly malaria parasite was decoded, scientists have now sequenced two others, opening the way for research into new drugs and vaccines.
Plasmodium falciparum, which is most common in Africa and is responsible for most malaria deaths, was sequenced in 2002; now a team of 40 scientists from around the world, led by a New York University researcher, has untangled Plasmodium vivax, the most common malaria in Asia and Latin America.
While vivax is rarely fatal, it can cause debilitating fevers and shakes for many days and lifelong brain damage. It also has a dormant stage that hides in the liver, causing recurrences months or years later, sometimes long after the victim has left the malarial area.
The parasite seems to have several ways to attack a red blood cell, but it does not cause the cells to twist into clumps, clogging tiny vessels in the brain, as falciparum does.
It has taken longer to sequence vivax because of greater interest in falciparum malaria and because the vivax parasite cannot be kept alive in the laboratory.
A second team sequenced the genome of Plasmodium knowlesi, which is most common in monkeys. It had not been known to infect humans, but scientists suspect that it is the killer in some deaths attributed to other parasites. Both studies were published last week in the journal Nature.