TSAKANE, South Africa — When she joined a trial of new tuberculosis drugs, the dying young woman weighed just 57 pounds.

Stricken with a deadly strain of the disease, she was mortally terrified. Local nurses told her the Johannesburg hospital to which she must be transferred was very far away — and infested with vervet monkeys.

“I cried the whole way in the ambulance,” Tsholofelo Msimango recalled recently. “They said I would live with monkeys and the sisters there were not nice and the food was bad and there was no way I would come back. They told my parents to fix the insurance because I would die.”

Five years later, Ms. Msimango, 25, is now tuberculosis-free. She is healthy at 103 pounds, and has a young son.