Optimal timing for the Influenza Vaccine

10 April 2020

Annual vaccination is the most important measure to prevent influenza and its complications. It is recommended for all people aged six months and over (unless contraindicated). Optimal protection against influenza occurs within the first three to four months following vaccination. Timing of vaccination should aim to achieve the highest level of protection during peak influenza season. This usually occurs from June to September in most parts of Australia. Vaccinating from April provides protection before the peak season.

Deferring vaccination to the beginning of winter may result in greater immunity later in the season, but may also result in missed opportunities for vaccination and lack of protection if the influenza season starts early.

Immunisation providers need to weigh up these factors for each person, and balance them with the challenge of vaccinating large numbers of people in a short time. 

Offer vaccination throughout the influenza season. It is never too late to vaccinate, because influenza can circulate all year. In particular, pregnant women and travellers can benefit from vaccination at any time of the year. 

Because of the high rate of influenza in the general population, vaccinating employees can result in workplace benefits such as increased productivity and reduced absenteeism.55 Employers should consider the benefits of offering influenza vaccine in their workplace, particularly for occupations at higher risk of influenza. See Vaccination for people at occupational risk.

Children aged six months to <nine years who are receiving their 1st lifetime dose should receive the vaccine as soon as possible after it becomes available. This helps to ensure enough time to receive a second dose (recommended ≥4 weeks later) before the influenza season starts.

The above information is sourced from the Australian Immunisation Handbook Influenza Vaccine section.

Useful resources for the flu season: