On Monday, Chicago magazine honored its “Chicagoans of the Year,” including north suburbanites Howard Morton and Tom von Geldern, who found a treatment for a parasitic disease known as river blindness.

The disease, caused by parasites attached to blackflies, results in painful skin nodules, often leading to blindness. Treatments for the disease existed, but were expensive, especially for the 37 million people in sub-Saharan Africa, who suffer from the parasite.

Morton and von Geldern worked together to discover an inexpensive oral medication that kills the parasite before it can spread. Both retired, they used their expertise as former employees of pharmaceutical company Abbvie to develop the drug.

Von Geldern joins Worldview to discuss why he spent his free time seeking a cure for river blindness.