The video begins with a boy discovering massive footprints in the dirt. “What is this creature?” he seems to think, as he and a group of villagers follow the tracks to a house. Inside, there’s a man with bulbous, swollen legs.

The man uses the awkward gathering as a teachable moment: “Filaria can infect anybody, at any time,” he tells the crowd.

The clip is part of an eradication campaign launched by the Indian Ministry of Health launched this year. The disease that has deformed the man’s legs is lymphatic filariasis, otherwise known as elephantiasis or “elephant’s foot” disease. As part of the effort, the ministry aims to hand out free medication to the 400 million Indians at risk of the disease,  The New York Times reported earlier this year.

Health workers in India and elsewhere will be helped along by a discovery that won the Nobel Prize for medicine on Monday. The scientists William Campbell and Satoshi Omura won half of the prize for developing avermectin, a drug whose derivative, ivermectin, has been used to treat hundreds of millions of people with filariasis and has nearly eradicated another parasitic infection, river blindness. (China's Tu Youyou was awarded the other half of the Nobel for discovering a drug that has vastly improved malaria treatment and reduced deaths from the disease.)

Filariasis, which is caused by worms spread by mosquitoes, afflicts mainly people in Africa and Asia. Worldwide, 120 million people are infected, and about 40 million are disfigured and incapacitated by it. The swelling occurs because the worms block lymphatic vessels, causing fluid to build up in the lower extremities. In addition to its disabling effects, the parasite can also cause pain and inflammation. Ivermectin protects against infection for about a year.

Omura said during a press conference that he made the crucial find on a golf course. He always carries a plastic bag with him for soil samples, the AP reported, and one day while out playing golf near Tokyo he scooped up some dirt containing the bacteria that would become essential for developing avermectin.

"I really wonder if I deserve this," Omura, an 80-year-old professor emeritus at Kitasato University in Japan, told Reuters in reaction to his win. "I have done all my work depending on microbes and learning from them, so I think the microbes might almost deserve it more than I do."

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