Narrated Abu Huraira:Allah's Messenger (ﷺ) said, "No 'Adwa." Abu Huraira also said: The Prophet (ﷺ) said, "The cattle suffering from a disease should not be mixed up with healthy cattle (or said "Do not put a patient with a healthy person as a precaution.") Abu Huraira also said: Allah's Messenger (ﷺ) said, "No 'Adwa." A bedouin got up and said, "Don't you see how camels on the sand look like deer but when a mangy camel mixes with them, they all get infected with mange?" On that the Prophet (ﷺ) said, "Then who conveyed the (mange) disease to the first camel?
Hadith No. 5773
Sahih al Bukhari