Prepared by Mawlana Mateen A. Khan MD and Dr. Ramzan Judge PharmD

Updated: 08/27/2026

Summary

Permissible influenza vaccines in the US for 2026-2027 season

• Fluarix
• FluLaval
• Fluzone
• Fluzone High-Dose
• Fluad
• mFlusiva
• Flucelvax (less favored)

Impermissible influenza vaccines in the US for 2026-2027 season

• FluMist
• Flublok

Discussion

Background on Influenza

Influenza (commonly known as the flu) is a seasonal viral illness that carries a significant health, economic, and social burden. CDC’s latest completed-season summary estimates that 2024–2025 influenza caused 51 million illnesses, 23 million medical visits, 710,000 hospitalizations, and 45,000 deaths, while vaccination prevented approximately 10 million illnesses, 5 million medical visits, 180,000 hospitalizations, and 12,000 deaths.

In addition to protecting healthy individuals, the vaccine benefits the sick by reducing their exposure to others (herd immunity). Therefore, the CDC and most American medical organizations recommend that everyone six months old and older receive a seasonal influenza vaccine each year.[i]

Improving vaccination rates among Muslims has been a struggle. Muslim-majority countries find their populations hesitant. [ii] Similar issues are faced among Muslim minority populations in the West due to concerns about the presence of impermissible ingredients in the vaccine.[iii]

The United States currently offers nine different commercially prepared vaccines.[iv] We reviewed package inserts and public records to evaluate the vaccines’ production methods and the presence of impermissible products. When necessary, we corresponded with the manufacturers. Table 1 compiles the available vaccines, dosages, and age range.

The vaccines vary in their methods of production and ingredients, which may pose religious challenges for Muslims. Below is a discussion of those challenges.

Challenge #1 – Methods of Production

Influenza vaccines are prepared through four different processes: egg-based, mammalian-cell-based, recombinant insect-cell-based, and cell-free mRNA production. Most strains are prepared through an egg-based manufacturing process. This involves injecting vaccine viruses into fertilized chicken eggs. Essentially, the viruses commandeer the egg as a factory, using its resources to replicate. The viruses are extracted and purified.[v] Islamically, this process per se is not an issue, as eggs are considered permissible.

mFlusiva manufactured by Moderna is an mRNA-based influenza vaccine newly available for the 2026–2027 season. Its mRNA is encapsulated in lipid nanoparticles composed of SM-102, cholesterol, DSPC, and PEG2000-DMG. Since cholesterol and similar lipid excipients may come from different sources, we corresponded with Moderna’s Medical Information team. The company confirmed in writing that mFlusiva contains no animal- or human-derived components and specifically that its cholesterol, DSPC, PEG2000-DMG, and SM-102 are not derived from animal sources. Although Moderna did not further specify whether each lipid is synthetic or plant-derived, none poses a concern based on its stated origin. Hence, mFlusiva is Islamically permissible.[vi]

Flucelvax, a product by Seqirus, is made by incubating influenza viruses in a particular animal cell line, Madin-Darby Canine Kidney (MDCK).[vii] The MDCK cell line was initially isolated in 1958 from an adult Cocker Spaniel dog.[viii] Dogs, like all predators, are ḥarām as Sayyidunā Ibn `Abbās (May Allah be pleased with him) narrated that Allah’s Messenger ﷺ prohibited every predator possessing canine teeth.[ix] Further, when cells like MDCK are removed from an animal, they are considered maytah (carrion) in Islamic terminology. The Prophet ﷺ informed us, “Whatever is cut from an animal while it is alive is carrion.”[x] Surah al-An`ām states that carrion is najis (impure) and ḥarām (impermissible).

Say, “I do not find, in what has been revealed to me, anything prohibited for anyone who eats it, unless it be carrion or blood that pours forth, or flesh of swine – because it is impure.[xi]

Hence, the initially harvested canine cells were najis and ḥarām. Since 1958, the cell line has undergone countless replication cycles in artificial environments, and the parent cells have long died off. Still, as progeny cells, they are impure and impermissible.

The MDCK cells used in Flucelvax are grown in a chemically defined medium that contains no materials of human or other animal origin. [xii] After viral propagation, the harvest undergoes clarification to remove cells and debris, followed by chemical inactivation, detergent disruption, and extensive purification to isolate the viral antigens. Despite these purification steps, trace amounts of residual host-cell proteins or DNA from the MDCK cells may remain, which could theoretically cause hypersensitivity reactions in susceptible individuals, as noted in the package insert. As outlined elsewhere on MuslimMed.org[xiii], the antigen is halal, and the trace contaminants are overlooked. Thus, the Flucelvax vaccine is permissible; however, it is less preferred since the other permissible vaccines appear to be free of contaminants.

Flublok is produced by expressing recombinant influenza hemagglutinin proteins in an insect cell line using a baculovirus (Autographa californica) vector. It is then used to infect an insect cell line (ExpresSF+) derived from the fall armyworm (Spodoptera frugiperda), which produces the desired influenza proteins. Insects, like the armyworm, fall into the category of al-khabā’ith explicitly mentioned in the Qur’an as ḥarām in Surah al-A`rāf.

[He ﷺ] makes unlawful for them impure things (al-khabā’ith).[xiv]

Similar to animal cell lines discussed previously, the progeny ExpresSF+ cells are impure and impermissible. Hence, the Flublok vaccine made from this method is also impermissible, particularly when other permissible alternatives exist.

Challenge #2 – Porcine Gelatin as a Stabilizer

FluMist contains porcine gelatin.[xv] The vaccine uses hydrolyzed porcine gelatin as a stabilizer. Gelatin is hydrolyzed collagen, which is extracted from collagen-containing tissue like skin and bones. The Qur’an declares that all porcine parts are najis and ḥarām.

Say, “I do not find, in what has been revealed to me, anything (out of the cattle under discussion) prohibited for anyone who eats it, unless it be carrion or blood that pours forth, or flesh of swine – because it is impure – or there be an animal slaughtered sinfully by invoking on it the name of someone other than Allah.” (Surah al-An`ām:145)[xvi]

He has but prohibited for you the carrion, the blood, the flesh of swine and what has been invoked upon with a name other than that of Allah. (Surah al-Naḥl:115)[xvii]

In earlier times, gelatin was prepared at home by cooking, causing the collagen to hydrolyze and break into peptides of varying lengths. Although the process today is commercialized and done through a series of chemical reactions, extraction, and purification, the result is not much different from home preparations. These peptides do not constitute a significant change (tabdīl al-māhiyah) from the original porcine collagen. Instead, gelatin is just fragmented, hydrolyzed collagen. The resulting gelatin is impermissible.[xviii] Hence, FluMist is impermissible, particularly when other permissible alternatives exist.

Exceptional Cases

If someone is relatively healthy and unable to take or obtain one of the permissible influenza vaccines, they should not take an impermissible vaccine. However, if a strong need exists and a permissible alternative is unobtainable, they may take normally impermissible vaccines.

As with other impermissible vaccines, practitioners and patients should employ shared clinical decision-making[xix] to determine if the vaccine constitutes a necessity in the Sharīʻah. Shared clinical decision-making ideally involves a discussion between the patient and a pious practicing Muslim practitioner adept at assessing the patient’s clinical risk for significant mortality and morbidity while considering the dictates of the Sharīʻah.

A necessity in the Sharīʻah arises when there is a high likelihood (ghalabah al-ẓann) of significant morbidity or mortality by contracting influenza, such as in the very old or patients with pre-existing significant comorbidities. Ideally, the Sharī`ah prefers a competent Muslim physician to determine this need based on the evidence at hand. The physician should be pious and have a basic understanding of the relevant Sharī`ah rulings.[xx] If no such individual is available, the practitioner should consult an Islamic scholar. Vaccinations mandated by the government, workplaces, or schools may also constitute a strong need.[xxi]

If the parties involved agree that the patient faces a significant threat, they may take a normally impermissible vaccine to ward off that threat. This need-based permissibility is valid only until an alternative permissible vaccine becomes available. In these situations, one may take (in order of preference) Flublok and FluMist.

Conclusion

Of the nine commercially available influenza vaccines available in the US for the 2026-2027 season, seven are Islamically permissible: Fluad, Fluzone, Fluzone High-Dose, Fluarix, FluLaval, mFlusiva, and Flucelvax. Flucelvax is less preferred compared to the other six. Muslim patients are advised to avoid Flublok and FluMist.

In exceptional cases, as outlined above, one may take Flublok and FluMist in order of preference.

Of note, vaccine formulations are subject to change year to year. The research presented here is accurate for the 2026-2027 season to the best of our knowledge.

Table 1: Influenza Vaccine Products for the 2026–2027 Influenza Season

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[i] https://www.cdc.gov/flu/prevent/whoshouldvax.htm.

https://www.cdc.gov/flu-burden/php/data-vis-vac/2024-2025-prevented.html

[ii] Ahmed, A. (2018) Outbreak of vaccine-preventable diseases in Muslim majority countries. Journal of Infection and Public Health, 11 (2), 153-155. doi.org/10.1016/j.jiph.2017.09.007

[iii] https://mcb.org.uk/mcb-updates/position-on-flu-vaccines/

[iv] https://www.cdc.gov/flu/professionals/acip/summary/summary-recommendations.htm

[v] https://www.cdc.gov/flu/prevent/how-fluvaccine-made.htm#targetText=The%20most%20common%20way%20that,for%20more%20than%2070%20years.&targetText=For%20flu%20shots%2C%20the%20influenza,and%20virus%20antigen%20is%20purified.

[vi] https://www.fda.gov/media/194120/download
Moderna Contact Center, personal communication by email with the authors, August 21, 2026, Medical Information reference MI-00291731.

[vii] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6177469/

[viii] https://en.wikipedia.org/wiki/Madin-Darby_Canine_Kidney_cells#targetText=Madin%2DDarby%20Canine%20Kidney%20(MDCK,as%20responses%20to%20growth%20factors.

[ix] عَنِ ابْنِ عَبَّاسٍ، قَالَ نَهَى رَسُولُ اللَّهِ صلى الله عليه وسلم عَنْ كُلِّ ذِي نَابٍ مِنَ السِّبَاعِ (مسلم 1934)

[x] مَا قُطِعَ مِنَ الْبَهِيمَةِ وَهِيَ حَيَّةٌ فَهِيَ مَيْتَةٌ (أبو داوود 2858، الترمذي 1480، ابن ماجه 3216)

وَعَلَى هَذَا يَخْرُجُ مَا إذَا قَطَعَ مِنْ أَلْيَةِ الشَّاةِ قِطْعَةً أَوْ مِنْ فَخِذِهَا أَنَّهُ لَا يَحِلُّ الْمُبَانُ وَإِنْ ذُبِحَتْ الشَّاةُ بَعْدَ ذَلِكَ؛ لِأَنَّ حُكْمَ الذَّكَاةِ لَمْ يَثْبُتْ فِي الْجُزْءِ الْمُبَانِ وَقْتَ الْإِبَانَةِ لِانْعِدَامِ ذَكَاةِ الشَّاةِ لِكَوْنِهَا حَيَّةً وَقْتَ الْإِبَانَةِ، وَحَالَ فَوَاتِ الْحَيَاةِ كَانَ الْجُزْءُ مُنْفَصِلًا وَحُكْمُ الذَّكَاةِ لَا يَظْهَرُ فِي الْجُزْءِ الْمُنْفَصِلِ وَرُوِيَ أَنَّ أَهْلَ الْجَاهِلِيَّةِ كَانُوا يَقْطَعُونَ قِطْعَةً مِنْ أَلْيَةِ الشَّاةِ وَمِنْ سَنَامِ الْبَعِيرِ فَيَأْكُلُونَهَا فَلَمَّا بُعِثَ النَّبِيُّ الْمُكَرَّمُ – عَلَيْهِ الصَّلَاةُ وَالسَّلَامُ – نَهَاهُمْ عَنْ ذَلِكَ فَقَالَ – عَلَيْهِ الصَّلَاةُ وَالسَّلَامُ – «مَا أُبِينَ مِنْ الْحَيِّ فَهُوَ مَيِّتٌ» وَالْجُزْءُ الْمَقْطُوعُ مُبَانٌ مِنْ حَيٍّ وَبَائِنٌ مِنْهُ فَيَكُونُ مَيِّتًا وَكَذَلِكَ إذَا قُطِعَ ذَلِكَ مِنْ صَيْدٍ لَمْ يُؤْكَلْ الْمَقْطُوعُ، وَإِنْ مَاتَ الصَّيْدُ بَعْدَ ذَلِكَ لِمَا قُلْنَا. (بدائع الصنائع في ترتيب الشرائع)

[xi] قُل لَّا أَجِدُ فِي مَا أُوحِيَ إِلَيَّ مُحَرَّمًا عَلَىٰ طَاعِمٍ يَطْعَمُهُ إِلَّا أَن يَكُونَ مَيْتَةً أَوْ دَمًا مَّسْفُوحًا أَوْ لَحْمَ خِنزِيرٍ فَإِنَّهُ رِجْسٌ أَوْ فِسْقًا أُهِلَّ لِغَيْرِ اللَّـهِ بِهِ

[xii] European Medicines Agency Assessment Report on Flucelvax Tetra. 18 Oct. 2018. Pg. 14.

[xiii] https://muslimmed.org/2023/11/21/position-statement/
https://muslimmed.org/2021/02/03/viral-vector-page/

[xiv] وَيُحَرِّمُ عَلَيْهِمُ الْخَبَائِثَ

(وَأَمَّا) الَّذِي يَعِيشُ فِي الْبَرِّ فَأَنْوَاعٌ ثَلَاثَةٌ: مَا لَيْسَ لَهُ دَمٌ أَصْلًا، وَمَا لَيْسَ لَهُ دَمٌ سَائِلٌ، وَمَا لَهُ دَمٌ سَائِلٌ مِثْلُ الْجَرَادِ وَالزُّنْبُورِ وَالذُّبَابِ وَالْعَنْكَبُوتِ وَالْعَضَّابَةِ وَالْخُنْفُسَاءِ وَالْبُغَاثَةِ وَالْعَقْرَبِ.

وَنَحْوِهَا لَا يَحِلُّ أَكْلُهُ إلَّا الْجَرَادَ خَاصَّةً؛ لِأَنَّهَا مِنْ الْخَبَائِثِ لِاسْتِبْعَادِ الطِّبَاعِ السَّلِيمَةِ إيَّاهَا وَقَدْ قَالَ اللَّهُ تَبَارَكَ وَتَعَالَى {وَيُحَرِّمُ عَلَيْهِمُ الْخَبَائِثَ} [الأعراف: 157] إلَّا أَنَّ الْجَرَادَ خُصَّ مِنْ هَذِهِ الْجُمْلَةِ بِقَوْلِهِ – عَلَيْهِ الصَّلَاةُ وَالسَّلَامُ – «أُحِلَّتْ لَنَا مَيْتَتَانِ» فَبَقِيَ عَلَى ظَاهِرِ الْعُمُومِ. وَكَذَلِكَ مَا لَيْسَ لَهُ دَمٌ سَائِلٌ مِثْلُ الْحَيَّةِ وَالْوَزَغِ وَسَامِّ أَبْرَصَ وَجَمِيعِ الْحَشَرَاتِ وَهَوَامِّ الْأَرْضِ مِنْ الْفَأْرِ وَالْقُرَادِ وَالْقَنَافِذِ وَالضَّبِّ وَالْيَرْبُوعِ وَابْنِ عِرْسٍ وَنَحْوِهَا، وَلَا خِلَافَ فِي حُرْمَةِ هَذِهِ الْأَشْيَاءِ إلَّا فِي الضَّبِّ (بدائع الصنائع في ترتيب الشرائع)

[xv] https://www.fda.gov/media/180697/download

[xvi] قُل لَّا أَجِدُ فِي مَا أُوحِيَ إِلَيَّ مُحَرَّمًا عَلَىٰ طَاعِمٍ يَطْعَمُهُ إِلَّا أَن يَكُونَ مَيْتَةً أَوْ دَمًا مَّسْفُوحًا أَوْ لَحْمَ خِنزِيرٍ فَإِنَّهُ رِجْسٌ أَوْ فِسْقًا أُهِلَّ لِغَيْرِ اللَّـهِ بِهِ

[xvii] إِنَّمَا حَرَّمَ عَلَيْكُمُ الْمَيْتَةَ وَالدَّمَ وَلَحْمَ الْخِنزِيرِ وَمَا أُهِلَّ لِغَيْرِ اللَّـهِ بِهِ

[xviii] Respectfully, the minority opinion considering gelatin to have undergone a significant transformation (tabdīl al-mahiyah) rendering its ruling changed seems doubtful for the reasons outlined. This is an extensive discussion. However, with the availability of clearly ḥalāl alternatives, the opinion given in this article is more cautious and avoids disagreement.

[xix] https://www.cdc.gov/vaccines/acip/acip-scdm-faqs.html#scdm
https://muslimmed.org/2023/11/21/position-statement-shared-decision-making-in-the-shari%ca%bbah/

[xx] وَجَوَّزَهُ فِي النِّهَايَةِ بِمُحَرَّمٍ إذَا أَخْبَرَهُ طَبِيبٌ مُسْلِمٌ أَنَّ فِيهِ شِفَاءً وَلَمْ يَجِدْ مُبَاحًا يَقُومُ مَقَامَهُ. قُلْت: وَفِي الْبَزَّازِيَّةِ وَمَعْنَى قَوْلِهِ – عَلَيْهِ الصَّلَاةُ وَالسَّلَامُ – «إنَّ اللَّهَ لَمْ يَجْعَلْ شِفَاءَكُمْ فِيمَا حُرِّمَ عَلَيْكُمْ» نَفْيُ الْحُرْمَةِ عِنْدَ الْعِلْمِ بِالشِّفَاءِ دَلَّ عَلَيْهِ جَوَازُ شُرْبِهِ لِإِزَالَةِ الْعَطَشِ (رد المحتار على الدر المختار)

[xxi] Imdād al-Fatāwa Jadīd maʻa Hāshiyah Shabbīr Aḥmad al-Qāsimī, 9:262