Passage: In 1903 Nicolle became Director of the Pasteur Institute in Tunis, where he did his Nobel Prize-winning work on typhus, bringing Hélène Sparrow with him as laboratory chief.  He was still director of the Institute when he died in 1936. He was a key researcher in discovering a deadly organism, Toxoplasma.

Question: Nicolle did Nobel-Prize winning word on what disease?
typhus