Several decades ago, Stan Brock nearly died when a horse kicked him in the head, while working on a ranch in the middle of the Amazon rain forest, not exactly the easiest spot to find a doctor.

When indigenous people in the region are struck by measles, influenza or malaria, thousands of people died for lack of medical attention.

Brock took the initiative, getting his pilot's license and a small plane to bring medical care to people in remote areas. In 1985, he started a nonprofit, Remote Area Medical. Since then, the all-volunteer group has held more than 663 medical clinics worldwide, providing free health care to half a million people.

Today, 60 percent of the medical care is provided not overseas but in America where large swaths of population have no dental, eye or general health care.

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