When is the right time to vaccinate against the flu?

No matter what month it is, getting vaccinated against flu is better than not getting vaccinated at all. However, getting timing of vaccination right can maximise the protection it provides. Booking your workplace vaccination program early can help you secure the best possible timing, and maximise the benefits to your business and your employees.

When is the flu vaccine available?

The flu vaccine usually becomes available for private use in Australia and New Zealand in March or early April each year. After that, it is usually available right through the flu season, although there have been some instances of shortages in the past.

Why does vaccination timing matter?

Research suggests that after a person is vaccinated, their level of protection against flu follows a ‘quickly up, slowly up, slowly down’ pattern. When they first receive the vaccine, it triggers their immune system to respond and start developing natural defences against the flu. It can take up to two weeks for this response to reach the level where it offers significant protection. After that, the person’s level of protection will slowly increase over coming weeks, usually peaking one to two months after vaccination.

After this peak, the level of protection slowly reduces over the following months. This decline in protection may occur more quickly for people over 65. While the flu vaccine can provide some protection for up to six months, its effect is strongest for approximately three to four months after it is administered. Therefore, it’s important to make sure that the period of greatest protection happens during the peak of the flu season.

Too early, too late, or just right?

If a person is vaccinated very early in the flu season, their level of protection (‘immunity’) will wear off before the peak of the flu season hits. For example, if they are vaccinated at the beginning of March, their immunity may peak around early June, and leave them at risk during the peak months of August and September. Whenever possible, it is best not to get vaccinated too early in the year. However, being vaccinated earlier is better than not being vaccinated at all.

If a person is vaccinated very late in the flu season, the delay between when they are vaccinated and when they reach maximum immunity will put them at risk during the peak months. For example, if they are vaccinated at the end of July, their immunity will not peak until around late October, and leave them at risk during the peak months of August and September. Therefore, it is important, wherever possible, not to leave vaccination too late. However, being vaccinated later is better than not being vaccinated at all.

Balancing these too sides of the equation the ‘sweet spot’ for vaccination is around April to June. This provides maximum protection around July to September, the usual peak of the flu season. Therefore, April to June is the ideal time to schedule your workplace vaccination program. But once again, the flu season is many months long, and some level of flu circulates in the community all year round. Therefore, vaccination any time is still worthwhile.

Other factors to consider

There may be reasons at the business/organisation level that a particular time is ideal to schedule a vaccination program. For example, if a large portion of your staff will be away during what might otherwise be considered the ‘ideal’ vaccination period (e.g. at a conference, on leave, or on extended business travel). In that case, it can be a good idea to schedule the vaccination program either side of the period of widespread absence. Because many more employees vaccinated a few weeks either side of the usual time is likely better than a much smaller number vaccinated at the usual time. Similarly, there may be seasonal variations in when you expect employees to be in contact with vulnerable people, or travelling, or in contact with the general public, which may also influence the ideal timing of vaccination.

Sometimes, variations in the timing of the flu season can also affect the optimal vaccination window. For example, the 2019 season begin unusually early, with many people catching summer flu’, and cases peaking in June and July (instead of August and September, as they usually would). Most people were not yet vaccinated when the season really took off in March. This led to an early rush on vaccines, leading to shortages. On the flip side, if the peak of a flu season is later than usual, the immunity of people who are vaccinated as per the recommended timing may peak a bit too early. Monitoring news about the flu season is a useful way to take these kinds of factors into account.

Book now to secure your choice of vaccination dates

The sooner you book your workplace vaccination program, the more choice you will have over when it is delivered. Getting the timing right will maximise the benefits to you and your business from your investment in your employee’s health. Contact us today to book your workplace vaccination program at a time that suits you.

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