Is squalene in the 25-26 flu shots?

1. Why this question matters and what the core claim says about ingredients

People ask whether squalene is in the 2025–2026 flu shots because squalene is used as an adjuvant component in some vaccines and has been the subject of public attention, so ingredient transparency affects public trust and decision-making about which vaccine to receive. The materials assembled for this analysis repeatedly note that MF59 is an oil-in-water emulsion whose oil phase is squalene, and that product Fluad uses MF59; that connection is explicitly documented in clinical and institutional ingredient listings, establishing the direct factual link between Fluad and squalene ^[1]. Other reviewed sources describing vaccine composition or national programs for 2025–2026 do not identify additional squalene-containing influenza products beyond Fluad, indicating that the presence of squalene is limited to that adjuvanted formulation in the current season’s formulations ^{[4] [5]}.

2. What the sources say about Fluad and MF59—clear linkage to squalene

Clinical and institutional ingredient summaries list Fluad as containing the MF59 adjuvant, and MF59’s components include squalene oil; this is the clearest and most direct pathway by which squalene appears in a licensed influenza vaccine product. The Children’s Hospital of Philadelphia ingredients summary explicitly associates Fluad with MF59 and its squalene component, and other analyses reiterate that MF59 (and related oil-in-water emulsion adjuvants such as AS03 and AF03 in broader literature) are squalene-based, confirming the mechanistic ingredient-level relationship ^{[1] [6]}. That means patients receiving Fluad would receive a formulation that includes a squalene-containing adjuvant, whereas patients receiving non‑adjuvanted inactivated or recombinant influenza vaccines from the standard product roster would not receive squalene.

3. What other official composition documents report for 2025–2026—absence of wider squalene use

Regulatory and national program documents that outline the recommended virus strains and programmatic choices for 2025–2026 focus on strain selection and vaccine types and do not enumerate squalene as a component of the general suite of influenza vaccines offered that season; these documents therefore do not contradict the narrower finding that squalene appears in Fluad but is not a listed ingredient across other 2025–2026 flu vaccines. Analyses of U.S. influenza vaccine composition for 2025–2026 and national program guidance examined for this review do not add any additional squalene-containing influenza formulations to the season’s portfolio, reinforcing that MF59/Fluad is the specific, named exception rather than a general ingredient found in all flu shots ^{[3] [5]}.

4. Where ambiguity remains and what was not found in the provided files

The assembled materials include multiple statements that do not explicitly mention squalene for certain documents or seasons, creating some apparent gaps where a reader might expect explicit ingredient lists for every listed product. Several of the provided sources either discuss season composition, strain recommendations, or broad adjuvant classes without listing every brand’s ingredient table; therefore, while there is clear documentation tying Fluad/MF59 to squalene, the absence of squalene from other product listings in these documents stems from those documents’ focus rather than a universal ingredient audit. The available analyses converge on Fluad as the identified squalene-containing product but do not supply a comprehensive, line-by-line ingredient table for every licensed flu vaccine for independent cross‑check within the provided corpus ^{[4] [7]}.

5. Implications for patients, clinicians, and transparency—what to do next

Patients and clinicians seeking to avoid or select a squalene-containing flu vaccine can act on the documented fact that Fluad contains MF59 (squalene) while other common flu vaccines listed for 2025–2026 do not list squalene; therefore choosing a specific product can control exposure to that ingredient. For definitive, brand-level verification beyond the documents provided here, consult product package inserts or manufacturer ingredient lists—these sources provide the authoritative, up-to-date ingredient statements for each licensed vaccine if any local or updated product formulations change after the documents in this review ^{[1] [2]}.