Brian Vastag suffers from myalgic encephalomyelitis/chronic fatigue syndrome, or ME/CFS for short. He is part of an NIH study of the disease, which is commonly called chronic fatigue syndrome.
Miriam Tucker for NPR
A man carries old plastic containers in March 2012 through the Kibera slum in Nairobi, Kenya. Kenyans living in poverty often collect plastics that they can turn into cash by taking it to companies that recycle it.
Carl de Souza/AFP/Getty Images
Lyme disease is spread by deer ticks like this one. A study finds that some people can be reinfected many times with the bacteria that cause the disease.
Lauree Feldman/Getty Creative Images