sentences:  In 1908 he conducted research at the Instituto Oswaldo Cruz, outside of Rio de Janeiro, and from 1910, carried out investigations of infectious diseases in Sumatra, German Samoa, Yap and Saipan.Prowazek studied epidemic typhus in Serbia (1913) and Istanbul (1914).Later, while Prowazek and Rocha Lima were working in a German prison hospital, they both became infected with typhus.