From Sahih Bukhari (Hadith 5770):
Narrated Abu Huraira: The Prophet (ﷺ) said, 'No 'Adwa (i.e. no contagious disease is conveyed to others without Allah's permission); nor (any evil omen in the month of) Safar; nor Hama" A bedouin said, "O Allah's Messenger (ﷺ)! What about the camels which, when on the sand (desert) look like deers, but when a mangy camel mixes with them they all get infected with mange?" On that Allah's Apostle said, "Then who conveyed the (mange) disease to the first (mangy) camel?
Reference: Bukhari 5770