The Messenger of Allah ﷺ said, "One whose animals are sick should not bring them to water alongside one whose animals are healthy."
قال رسول الله ﷺ: لا يورد ممرض على مصح.
No references are available.
Reported by Bukhari in the Book of Medicine (5771, 5774), and Muslim in the Book of Greetings (2221), both through chains from Zuhri, from Abu Salama bin Abdul-Rahman bin Awf, from Abu Hurairah, who said, and then he related it. In Muslim's version there is a lengthy account concerning Abu Hurairah's silence regarding the hadith "there is no contagion," which was mentioned earlier under that hadith, while Bukhari's version is abbreviated.Nawawi said in his commentary on Sahih Muslim, "His saying 'the owner of sick camels should not bring them to water alongside the owner of healthy camels' - the word 'yurid' (bring to water) is with a kasra on the ra, and 'mumrid' and 'musihh' both have a kasra on the ra and the sad respectively, and the object of 'yurid' is omitted, meaning he should not bring his sick camels. The scholars said that the mumrid is the owner of sick camels, and the musihh is the owner of healthy camels. So the meaning of the hadith is that the owner of sick camels should not bring his camels to water alongside the camels of the owner of healthy camels, because the healthy camels might be afflicted with sickness by the act and decree of Allah, exalted is He, which He has made customary, not by the nature of the sick camels themselves. This would cause harm to the owner of the healthy camels through their sickness, and it might cause him even greater harm if he came to believe in contagion by nature, for then he would fall into disbelief. And Allah knows best." End of quote.