All the influenza vaccines available in Australia are either split virion or subunit vaccines. They are prepared from purified inactivated influenza virus that has been cultivated in embryonated hens’ eggs (standard influenza vaccines and adjuvanted influenza vaccine) or propagated in Madin-Darby canine kidney (MDCK) cells (cell-based influenza vaccine).
All these vaccines are quadrivalent as they contain 4 influenza virus strains – 2 influenza A subtypes and 2 influenza B lineages.
Standard (egg-based) influenza vaccines contain 15 µg of haemagglutinin per strain per dose with no adjuvant. Similarly, the available cell-based influenza vaccine contains 15 µg of haemagglutinin per strain per dose with no adjuvant.
The available adjuvanted influenza vaccine is egg-based, and contains the standard 15 µg of haemagglutinin per strain per dose, with MF59 as the adjuvant. The adjuvanted influenza vaccine is formulated to induce a greater immune response than standard influenza vaccines.
High-Dose (egg-based) influenza vaccines contain 60 µg of haemagglutinin per strain per dose with no adjuvant.
Although egg-based vaccines may contain traces of egg-derived protein (ovalbumin), they contain less than 1 μg of ovalbumin per dose.