Cunningham had traveled to Sierra Leone to help treat patients amid a deadly Ebola outbreak. On Jan. 1, 2015, he met Esatu, a 3-year-old girl stricken with the deadly virus. “She was covered in diarrhea. She was covered in vomit,” he said. “I didn’t think she was going to live longer than the time it would take to triage her and get her into our unit.” He said that only 25 percent of children under 5 survive Ebola. Watch him tell Esatu’s surprising story.