Position Statement: Two doses of influenza vaccine during a single flu season

There is no evidence that two doses of the influenza vaccine will provide either stronger or longer protection against influenza.

Immunisation Coalition

Two doses of influenza vaccine during a single flu season

 Statement date: 24 April 2020

Background: 

  • All Australians are encouraged to get the influenza vaccine this year (2020). 
  • The timing for starting influenza vaccination has been brought forward. The rationale is to:
    • ensure that vulnerable groups are covered before influenza arrives
    • reduce the burden on GPs and hospitals at a time when COVID is placing considerable demands on the health care system
    • avoid having to manage large number of cases of influenza and COVID at the same time

Position: 

  • The influenza vaccine, especially against the H3 strain, tends to lose some effectiveness (around 6-8% per month) after 3-4 months. 
  • The enhanced flu vaccine, recommended to those 65 years and older, was specifically designed (and demonstrated) to improve the effectiveness against the H3 strain of the influenza vaccine
  • There is no evidence that two doses of the influenza vaccine will provide either stronger or longer protection against influenza
  • There is some evidence that the enhanced vaccine available to those 65 years and older does provide better protection against hospitalisation from getting influenza.
  • There is limited evidence that the duration of protection against influenza is longer when the older person receives an enhanced influenza vaccine.

Page Published: 24 April 2020 | Page Updated: 1 December 2021