How Nature Inspired the Medicine Nobel Prize Winners to Fight Parasites

Their discoveries saved the lives of millions of people around the world


This year, the Nobel Prize in Physiology or Medicine will be shared by three scientists for their work on fighting some of the world’s most common parasitic diseases. The Nobel committee announced today that half of the the prize will go to Tu Youyou, who discovered a critical antimalarial drug, while the other half will be split between William C. Campbell and Satoshi Ōmura for developing a drug to treat roundworm.

“The two discoveries have provided humankind with powerful new means to combat these debilitating diseases that affect hundreds of millions of people annually,” the Nobel committee said in a statement. “The consequences in terms of improved human health and reduced suffering are immeasurable.”

Parasitic diseases can be devastating, especially for millions of people living in sub-Saharan Africa, Latin America and South Asia. Malaria, which is caused by a single-celled parasite spread by mosquito bites, kills about 450,000 people every year (many of whom are children), while diseases caused by parasitic worms affect almost a third of the world’s population each year, Lawrence K. Altman reports for The New York Times.

While most of the research done by the three scientists was conducted during the 1960s and ‘70s, the treatments they developed continue to be some of the most effective in combating malaria and diseases caused by roundworm, such as river blindness and Lymphatic filariasis, which is more commonly known as elephantiasis, Ian Sample reports for The Guardian.

Although Tu began researching antimalarial drugs in the late 1960s, her work wasn’t published until 1977. Tu was assigned by Mao Zedong to work on a secret military operation known only as “523.” Dedicated to finding new drugs to treat malaria cases that were rampant in southern China and devastating their allies in North Vietnam, Tu eventually turned to traditional medicines after trials of synthetic drugs failed to treat the disease, Phil McKenna wrote for New Scientist in 2011.

“By the time I started my search, over 240,000 compounds had been screened in the US and China without any positive results,” Tu told McKenna at the time.

Tu’s work eventually paid off with her discovery of artemisinin, a drug that is still one of the most effective antimalarial treatments used today. Appropriately, she identified the drug after examining a 1600-year-old traditional Chinese medicine she found in a text called “Emergency Prescriptions Kept Up One’s Sleeve,” McKenna writes.

Around the same time, Ōmura and Campbell were researching treatments for roundworm, an intestinal parasite that infects 18 million people a year. When the roundworm nematodes die, they release toxic substances in the host’s eyes that can lead to irreversible blindness, as well as elephantiasis, which causes swelling of the limbs. Prior to 1970, in some West African communities, about 50 percent of men over the age of 40 were blind from the parasite, Rachel E. Gross writes for Slate.

Ōmura scoured soil samples from all over Japan, searching for microbes that could be used to fight microbial diseases. But when Campbell took a look at some of his findings, he realized that one species was extremely effective in fighting roundworm. This discovery led to the development of the drug avermectin, which has been instrumental in the work to eradicate river blindness.

“I did good things,” Ōmura said when he learned he had won this year’s Nobel Prize. “But there are many, many good researchers in the world.”

Thanks to the work done by these three scientists, millions of people are still alive today.

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