Al-Imām Ibn Bāz (Allāh’s mercy be upon him)
If the physicians (who are competent) confirm that a particular disease is contagious (by Allah’s permission), then it is a must for the guardians of the sick person to seclude him in a suitable place in their home and other people should not mix with him due to the saying of the Prophet (salallāhu ‘alaihi wasallam):
لاَ ضَرَرَ وَلاَ ضِرَارَ
“There should be neither harming [of other people] nor reciprocating harm.” This is a hasan hadīth reported by Ibn Mājah (no. 2341).
Such a person should pray all his prayers in full at home including Jumu’ah, except that he prays four rak’ahs Dhuhr at home instead of Jumu’ah. If his sickness is hard upon him, he can combine Dhuhr with ‘Asr (at either prayer time), and Maghrib with ‘Ishā (at either prayer time), and Fajr at its time.
See, Al-Jāmi’ fī Fiqhil-‘Allāmah Ibn Bāz (p. 1179).
Al-Imām Al-Albāni (Allāh’s mercy be upon him)
“As for a person’s leftovers (suʾr), then it is pure in a general sense, however, it is not described that it is a cure of any sort and nor that it is an ailment. O Allāh, except in one specific situation, when it is established that:
- This person is actually ill.
- That he is afflicted with a contagious disease.
- That this contagious disease is caused by a microbe.
- And that this microbe may be transmitted not only through drink but also by way of physical contact, the [sick] person may touch him.
So here, there is no issue with taking precaution.
But we do not make it a habit in daily life. So the meaning [here] is that this is a whispering (waswasah) which destroys personal ties and human relations which are established between people. The foundation is that every person’s leftovers and interaction with them is that he is upon fiṭrah (original disposition) and upon health and well-being.”
Allah, the Most High, knows best but what is apparent is that precaution is valid if the conditions stated by Shaikh Al-Albāni (rahimahullāh) are met. And what the Shaikh has stated, alhamdulillāh, agrees with the texts and sound reason.
 There is no such thing as an infectious or contagious disease except by Allah’s permission and no disease afflicts a person or passes from person to person by itself. It is Allah who decrees it to occur.
 The food on a plate one has eaten from with hands or the drink in a vessel one has drunk from, and it refers to whatever separates from the body (from the skin, saliva) that another person may then come into contact with by eating from the same food or drinking the same drink.
 There is no title to this cassette or series, and it is simply labelled as “Miscellaneous Issues”, no. 211. For the recording refer to https://www.al-albany.com/audios/content/3378
 The fatwa of Shaikh Al-Albāni was referenced and translated by Abu Iyād Amjad Rafiq.