There is no infection, no safar, no hama. A desert Arab said: Allah's Messenger, how is it that when the camel is in the sand it is like a deer-then a camel afflicted with scab mixes with it and it is affected by sub? He (the Holy Prophet) said: Who infected the first one?

There is no transitive disease, but he is also reported to have said: A sick person should not be taken to one who is healthy. Abu Salama said that Abu Huraira used to narrate these two (different ahadith) from Allah's Messenger (ﷺ), but afterwards Abu Huraira became silent on these words: There is no transitive disease, but he stuck to this that the sick person should not be taken to one who is healthy. Harith b. Abu Dhubab (and he was the first cousin of Abu Huraira) said: Abu Huraira, I used to hear from you that you narrated to us along with this hadith and the other one also (there is no transitive disease), but now you observe silence about it. You used to say that Allah's Messenger (ﷺ) said: There is no transitive disease. Abu Huraira denied having any knowledge of that, but he said that the sick camel should not be taken to the healthy one. Harith, however, did not agree with him, which irritated Abu Huraira and he said to him some words in the Abyssinian language. He said to Harith: Do you know what I said to you? He said: No. Abu Huraira said: I simply denied having said it. Abu Salama sad: By my life, Abu Huraira in fact used to report Allah's Messenger (ﷺ) having said: There is no transitive disease. I do not know whether Abu Huraira has forgotten it or he deemed it an abrogated statement in the light of the other one.

There is no transitive disease, no ill omen, no ghoul.