Evidence of Malaria origins, could lead to vaccine development

Aug 4 2009

"Malaria may have jumped to humans from chimpanzees much as AIDS did, U.S. researchers reported on Monday in a [Proceedings of the National Academy of Sciences] study they hope could help in developing a vaccine against the infection," Reuters reports.

The researchers found evidence the Plasmodium falciparum parasite that "causes most cases of malaria is a close genetic relative of a parasite found in chimpanzees," the news service writes (8/4). 

According to the Mail Online, chimpanzees are known to harbor the Plasmodium reichenowi parasite, which is closely related to P. falciparum. Although most researchers assumed these parasites co-existed separately in humans and chimpanzees for the last five million years, "the new research shows the chimp parasites are wide-ranging, indicating malaria went from animals to humans in much the way HIV, SARS and swine flu did. It suggests P. falciparum evolved from P. reichenowi," the publication writes. "Discovery of these parasites shows a broader range of relatives to the human parasite, some of which might provide key insights in drug development or act as vaccines that may help prevent human malaria," said Francisco Ayala, an evolutionary biologist, and lead author on the study, (8/4).

The other lead author Nathan Wolfe, of Stanford University and the Global Viral Forecasting Initiative, said, "It is now clear that a new disease that successfully jumps from an animal to a human can last not just for decades, but millennia or more," the Associated Press reports. As a result, the "task of stopping future disease spillovers from animals to humans vital, not only for saving lives today, but for the health of people for many generations to come," he said.

According to Wolfe, a better understanding of the chimp parasites could lead to improved malaria medicine or the development of a vaccine. He noted that early smallpox vaccines were developed from the related cowpox. The research was funded by the National Institutes of Health, Tufts University and the National Geographic Society (Schmid, 8/3). National Geographic (Avasthi, 8/3) and NPR (Hamilton, 8/3) also covered the story.