Sahih Muslim
The Book on Salutations and Greetings (Kitab As-Salam)
Book Number: 026 / Hadith Number: 5509
Abu Huraira reported Allah's Messenger (may peace be upon him) as saying: There is no trahsitive disease. Thereupon a desert Arab stood up. The rest of the hadith is the same and in the hadith transmitted on the authority of Zuhri' the Prophet (may peace be upon him) is reported to have said: There is no transitive disease, no safar, no hama.