Sahih Al-Bukhari — Hadith #5774

Narrated by Abu Huraira: The Messenger of Allah (peace and blessings be upon him) said, “There is no contagion.” Abu Huraira also reported that the Prophet (peace and blessings be upon him) said, “Sick animals should not be mixed with healthy animals.” (Or he said, “Do not put a sick person with a healthy person, as a precaution.”) Abu Huraira also reported that the Messenger of Allah (peace and blessings be upon him) said, “There is no contagion.” A Bedouin stood up and said, “Do you not see that camels in the desert resemble gazelles, but when a camel with mange joins them, they all catch mange?” The Prophet (peace and blessings be upon him) replied, “Who transmitted the disease to the first camel?”