Al-Matalib al-'Aliyah 2492 — There is no contagion, fleeing

It is narrated from Abu Talhah al-Khawlani (may Allah have mercy on him) that Sayyiduna Umayr bin Sa'd (may Allah be pleased with him), who because of his matchless qualities was called "Nasij Wahdihi" (unique of his age), was with a few people of the land of Palestine. We were sitting on a large platform in his house when he said to his servant: O boy! Water the animals. In the house there was a large stone trough, and the servant brought them to be watered. He asked: Where is such-and-such a she-camel? The servant submitted: She has mange, and blood (or water; the narrator Ibrahim is in doubt) is dripping from her body. He ordered: Bring her too to be watered. A man present in the gathering said: (If she is put with the other camels) then all the camels will get mange this way. He said: Water her, for I heard the Messenger of Allah (peace and blessings be upon him) say: "Disease (flying across and) infecting (by itself) has no reality, nor is taking bad omens permissible, nor does the hamah (the owl, or some superstition of the Time of Ignorance) have any standing. Have you not seen the camel that is (perfectly healthy) in the desert, and then suddenly a mark appears on the raised flesh of its chest (kirkiratihi) or the soft parts of its belly (maraqqihi) which was not there before? So (tell me), who made the first camel ill?"
Musnad Abi Ya'la: 2492. Its chain is hasan (good); al-Hafiz al-Haythami declared its narrators in Majma' al-Zawa'id to be narrators of the Sahih.