Carlos Chagas (b. July 9, 1879, Oliveira, Brazil–d. November 8, 1934, Rio de Janeiro, Brazil), was a Brazilian sanitary physician, scientist and bacteriologist who worked as a clinician and researcher. He discovered Chagas disease in 1909. Chagas' work holds a unique place in the history of medicine. Chagas was also the first to discover and illustrate the parasitic fungal genus Pneumocystis, later infamous for being linked to PCP (pneumocystis pneumonia in AIDS patients).