While on assignment for National Geographic at a children’s hospital in Zambia I saw David Miti, a man without legs, sitting on a bench making crutches. The poetry of the moment hit me and I asked if he would share his story. Miti built a career as a truck driver and a carpenter. Then, at age 34, his life changed forever.

“The day started with a fever,” Miti recalls. “I went to a hospital and got medicine, but after I went home I discovered a blister on my left leg. Then after some hours there was another blister on the other leg. Then my legs turned black.”

Mr. Miti was diagnosed with gangrene, a condition in which body tissue dies