The Messenger of Allah ﷺ stood among us and said, "Nothing transmits disease to another."An Arabi said, "Messenger of Allah, a mangy camel with a sore on its tail mixes with the herd, and then the entire herd becomes mangy."The Messenger of Allah ﷺ replied, "Then who gave it to the first one? There is no contagion and no Safar superstition. Allah created every soul and decreed its lifespan, its provision, and its afflictions."
حدثنا بندار حدثنا عبد الرحمن بن مهدي حدثنا سفيان عن عمارة بن القعقاع حدثنا أبو زرعة بن عمرو بن جرير قال حدثنا صاحب لنا
قام فينا رسول الله ﷺ فقال لا يعدي شيء شيئا فقال أعرابي يا رسول الله البعير الجرب الحشفة بذنبه فتجرب الإبل كلها فقال رسول الله ﷺ فمن أجرب الأول لا عدوى ولا صفر خلق الله كل نفس وكتب حياتها ورزقها ومصائبها
[Sahih]. Ahmad also reported it, 1/440, from Abdul-Rahman bin Mahdi, from Sufyan Thawri. Saeed bin Masruq followed him in narrating it, as found in Tahawi's Maani Athar, 4/308. The hadith has supporting witnesses, and the companion mentioned in it is indeed a companion of the Prophet, as noted in Tahawi.On this subject there are also reports from Abu Hurairah [Bukhari, no. 5717, 5757, and Muslim, no. 2220], Ibn Abbas [Ibn Majah, no. 3539], and Anas [mentioned earlier, no. 1615].Muhammad bin Amr bin Safwan is Muhammad bin Uthman bin Abu Safwan Thaqafi, and the report of Ali bin Abdullah Madini concerning him is sahih.