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This is Scientific American’s 60-Second Science. I’m Steve Mirsky. Got a minute?

A new development in malaria¹:

“Plasmodium vivax, the world’s most common malaria parasite², now infects people previously³ considered to be resistant⁴.”

Peter Zimmerman from Case Western Reserve University school of medicine spoke⁵ at the AAAS meeting in Washington on February 19th.

“So, red blood cells of most African people do not express the Duffy blood-group protein. Now, the Duffy blood-group protein is essentially⁶ necessary for Plasmodium vivax to get into the red cell. Duffy-negative Africans have been considered to be resistant to Plasmodium vivax.”

Zimmerman studied Malagasy populations on Madagascar. He found that 10 percent of Duffy-negative subjects were in fact infected with Plasmodium vivax.

“So we’ve shown that Plasmodium vivax has cleared Duffy negativity. If Plasmodium vivax is evolving to learn how to infect the Duffy-negative red cell, then a large continent of people suddenly becomes susceptible⁷ to a new form of malaria.”