Younger people need to keep up to date with vaccinations to reduce long COVID risk

To prevent severe illness, adults over 18 years of age are advised to have a COVID-19 vaccine booster if it’s been six months or more since a past infection or their last vaccination, the latest advice from ATAGI says, as immunity starts to wane after this point.

Vaccination rates are highest among those aged over 65, but it’s especially important to strongly advise younger people to keep their COVID vaccinations up to date, says Professor Michael Toole, associate principal research fellow at the Burnet Institute.

The peak age-range for long COVID is 35-55, yet this group tends to lag in their vaccinations, despite evidence of a protective effect against long COVID.

“There’s very clear data that being up to date with your vaccines reduces the likelihood of long COVID by at least 30 to 40%,” Professor Toole says.

However, Australians remain under-vaccinated, with almost 73% of the eligible population having had a third vaccination and around 45% had a fourth, according to the Department of Health’s vaccine rollout data of February 2023.

“The important message from ATAGI is that from now on, six months after the previous infection or booster, get another one,” Professor Toole says.

For those adults who have had all the recommended doses of the COVID-19 vaccine, this would be the fifth dose.

At this time, a booster dose is not recommended for children and adolescents aged under 18 who don’t have any risk factors for severe COVID-19.

Only those aged 5-17 years with medical comorbidities or disability with significant or complex health needs should consider a booster dose, according to ATAGI.

The advice for those 18 years of age or older is to have the booster that’s due according to the number of previous doses someone has had.

“I think we’ll stop counting and giving numbers to them. We’ll just say, ‘you’re up to date with your vaccine if you get one every six months’. And they may or may not be new vaccines,” Professor Toole said.

When it comes to which vaccine to have as a booster, ATAGI says all available vaccines will provide some benefit; however, bivalent mRNA booster vaccines are preferred. These include the Pfizer Original/Omicron BA.4/5, as well as Pfizer Original/Omicron BA.1 and Moderna Original/Omicron BA.1. ATAGI is currently reviewing Moderna Original/Omicron BA.4/5 for effectiveness.

All vaccines will provide protection against infection and severe disease, although studies indicate BA.4/5-based vaccines may induce higher neutralising activity against Omicron subvariants (including BQ.1 and XBB) than original vaccines or BA.1-containing vaccines, providing better protection against hospitalisation and death.

The bivalent Original/Omicron BA.1 vaccines are only registered for people aged 18 years and over, while the Pfizer bivalent Original/Omicron BA.4/5 vaccine is registered for use from 12 years of age. ATAGI also notes that a COVID-19 vaccine can be co-administered with influenza and other vaccines.

Professor Toole will be giving a much more comprehensive COVID update at Healthed’s FREE webcast on Tuesday, 7 March. Register here to attend.