Bold truth: seasonal flu vaccines change every year because influenza viruses mutate, so we reinvent the shot to target what’s circulating. And this is the part most people miss: that yearly update is not simply a routine tweak, but a careful, coordinated effort guided by global surveillance and expert recommendations.
Overview of 2026 Seasonal Influenza Vaccines
Influenza vaccines are reformulated annually to match the strains that are most likely to spread in a given season. This practice helps maximize protection and is why vaccination is recommended every year. In 2026, Australia’s national vaccine committee reviewed current data on influenza in the southern hemisphere, including recent circulating strains, antigenic and genetic information, and the immune responses expected from the 2024–2025 vaccine formulations. They also considered the availability of candidate vaccine viruses and reagents. Based on this review and the World Health Organization’s guidance, the committee approved the 2026 southern hemisphere vaccine composition. Notably, two new strains were added compared with the 2025 Australian vaccine: a A(H1N1)-like strain and a A(H3N2)-like strain.
Egg-based versus cell-based vaccines
There are two primary production methods for the 2026 trivalent vaccines (which include three strains): egg-based and cell-based. The egg-based, trivalent vaccines include: an A/Missouri/11/2025 (H1N1)pdm09-like virus, an A/Singapore/GP20238/2024 (H3N2)-like virus, and a B/Austria/1359417/2021 (B/Victoria lineage)-like virus. The cell-based, trivalent vaccines include: an A/Missouri/11/2025 (H1N1)pdm09-like virus, an A/Sydney/1359/2024 (H3N2)-like virus, and a B/Austria/1359417/2021 (B/Victoria lineage)-like virus. The WHO has stated that the B/Yamagata lineage is no longer needed for seasonal vaccines, since this lineage has not circulated in several years, a stance supported by Australia’s AIVC.
Vaccine eligibility and availability in Australia for 2026
Australia is transitioning to a trivalent formulation for its southern hemisphere season in 2026, meaning B/Yamagata will not be included in vaccines this year. Seven influenza vaccines will be available in 2026, with specific age indications for each product. FluMist, a nasal spray live attenuated vaccine, is new to the Australian market in 2026.
For general use through the National Immunisation Program (NIP), most vaccines are provided free of charge, but some trivalent vaccines are private-market options for certain age groups. In 2026, FluMist will be accessible on the private market and through some state programs. Doses for all ages are 0.5 mL, except FluMist, which is 0.2 mL intranasal. Detailed product information and COIs can be found on the TGA’s product labeling resources.
Children and older adults
All children aged 6 months to under 5 years are eligible for free annual influenza vaccination under Australia’s NIP. Among the registered vaccines for children 6 months and older are Flucelvax, Fluzone, Influvac, and Vaxigrip, with FluMist (the nasal spray) also available for children aged 2 to under 18 years; some states sponsor FluMist for children within narrower age ranges.
People under 65 and those 65 and older have tailored options. Under 65s who are at risk—such as Indigenous Australians, pregnant people, and those with certain medical conditions—may receive Flucelvax or Vaxigrip via the NIP; Fluzone and Influvac remain private-market options. For adults 65 and older, Fluad (adjuvanted) and Fluzone HD (high-dose) are specifically recommended; all individuals 65+ are eligible for free influenza vaccination through the NIP.
Vaccine ingredients and safety notes
Vaccine ingredient information is listed on each product’s label, PI, and CMI leaflets, available through manufacturer resources or the TGA database. Most vaccines used this season do not contain thiomersal/mercury. Formaldehyde may be used in early manufacturing stages as an inactivation agent but is removed before final testing and release. All seasonal vaccines available this year are latex-free, though trace contact with latex-containing instruments cannot be entirely excluded. Fluad is the only product with an adjuvant to boost the immune response in people over 50, while Fluzone HD contains a higher antigen amount. FluMist remains the only intranasal option and is approved for children and adolescents.
Egg-based vaccines generally use eggs in production; Flucelvax is produced in mammalian cell culture and does not contain egg proteins.
Vaccination timing and adverse event monitoring
Health authorities and clinicians will monitor adverse events as the 2026 vaccination program rolls out. If you have concerns about a potential reaction, consult a health professional for personalized advice. For more information, health professionals can refer to ATAGI’s influenza statements, and consumers can check NPS MedicineWise and the TGA resources for vaccine specifics. If adverse events occur, they should be reported to the appropriate state or territory program to support ongoing safety surveillance.
