It is mentioned in the Quran, with regards to honey:
“ There emerges from their bellies a drink, varying in colours, in which there is healing for people”. (Quran: An-Nahl-69)
Imam Qurtubi has elaborated on the meaning of this particular verse, “Allah (swt) uses the term ‘in which there is healing for people’ which is proof and guidance on the necessity of taking medicine or other substances for healing purposes.” (Tafsir al-Qurtubi, Volume 1 page 138).
There are also many narrations from the collections of hadith where the Prophet (pbuh) has allowed and sometimes ordered his companions to seek treatment.
In a hadith narrated by Imam Muslim from Jabir bin Abdullah (ra), the Prophet (saw) said, “Every illness has a cure, and when the proper cure is applied to the disease, it ends it, Allah willing.” (Sahih Muslim, volume 14 page 191).
Usamah bin Syariik (ra) said, “I was with the Prophet when the Bedouins came to him and said, ‘O Messenger of Allah, should we seek medicine?’ He said,’Yes, O slaves of Allah, seek medicine, for Allah has not created a disease except that He has also created its cure, except for one illness.’ They said, ‘And what is that?’ He said, ‘Old age’. (Narrated by Abu Daud, see ‘Aun al-Ma’buud’ volume 10 page 334)
From these hadiths, Imam Nawawi opined that seeking medical treatment and healing is ‘mustahabb’ (recommended). The same conclusions were derived from the ulama’ (scholars) of the Syafii’ mazhab or school of Islamic jurispundences (See Sahih Muslim).
Imam Abu Ishaqasy-Syaerozy, the author of the book al-Muhadzab, said, “If a Muslim falls ill, it is compulsory for him to be patient and if he so wishes, to seek medical treatment/healing”. (al-Muhadzab volume 5 page 94). Hence, in seeking medical treatment/healing, the initial hukum (authoritative law in the shari’ah) is “permissible”, but can become “compulsory” under certain circumstances.
One example is when the omission of seeking medical treatment or healing, in someone who is suffering from an illness, will endanger him or cause his death.
When a particular medicine has been well researched and scientifically proven to cure a particular illness and non-treatment may lead to definite mortality (death) or morbidity (sickness), the benefit of treatment is clear, scholars of law would rule that refusal of treatment is haram (forbidden).
“Hence, in seeking medical treatment/healing, the initial hukum (authoritative law in the shari’ah) is “permissible”, but can become “compulsory” under certain circumstances.”
This is rationalised as the preservation of life as stipulated in the maqasid shari’ah based on the quranic injunction “saving of one life is as though the entire human race is saved”.
When we understand the basics of shari’ah rulings on seeking medical treatment, it is easier to put into context the status of rulings surrounding immunisation.
Immunisation is the administration of vaccines to prevent the occurrence of a targeted disease. They have been demonstrated to be effective in global public health programmes, diminishing, eliminating and eradicating dangerous diseases.
The medical, social and economical benefits conferred by immunisation programmes are impactful and unprecedented compared to other public health programmes. Except for a few conservative Muslim scholars, virtually all distinguished Muslim scholars, national fatwa councils and international majma’fiqh (fatwa councils) endorse global immunisation programmes and urge all believers to prevent the spread of infectious vaccine-preventable diseases.
The custodians of the two holy cities, Makkah and Madinah, has even made it mandatory for all pilgrims to immunise against invasive meningococcal disease and other diseases, namely polio, yellow fever (if coming from endemic countries) prior to performing the hajj or umrah.