Rocky Mountain Spotted Fever is one of the deadliest tickborne diseases in the United States, often killing people within about a week if left untreated. At one point, the San Carlos Apache Reservation had rates of infection 150 times the national average. But now, they've achieved a huge milestone — no deaths from the disease in at least five years. NPR science correspondent Pien Huang and producer Megan Lim visited the reservation to see the program that led to their success.