Booster shots now available sooner for fully vaccinated, Moderna gets ATAGI approval

The emergence of new COVID-19 variant Omicron has seen advice from the nation’s vaccine advisory group on the timing of booster shots change as it hands down a recommendation that Moderna’s jab can be used as a third immunisation.

The Australian Technical Advisory Group on Immunisation (ATAGI) now recommends COVID-19 booster vaccination for anyone aged 18 and older who completed their primary course five or more months ago.

This change is down from a previous recommendation of six months after the second shot, and comes in light of the new variant of COVID-19 called Omicron.

“Evidence is still incomplete on the transmissibility, capacity to cause severe disease and overall impact of the Omicron variant. While data suggest that past infection with an earlier variant does not provide significant protection against infection, it remains unclear whether prior infection may reduce severity,” ATAGI said.

“Early data suggest that the protection provided by COVID-19 vaccination against infections with the Omicron variant is impaired compared to those with the Delta variant, but further data are required on the effectiveness against severe disease.

“Preliminary data suggest that the increased antibody levels generated following a COVID-19 vaccine booster dose may offer improved protection against the Omicron variant. However, the correlation between antibody levels in laboratory studies and protection against infection and severe disease is not yet established.”

With Moderna now recommended by ATAGI as a booster shot and provisional approval for the jab given by the Therapeutic Goods Administration (TGA) last week, Australians can choose between receiving a Pfizer (Comiranty) Moderna’s Spikevax shot as a booster.

ATAGI considers the Moderna and Pfizer COVID-19 vaccines to be “equally acceptable” as booster shots for those aged 18 and older, including pregnant women.

“Both mRNA COVID-19 vaccines are preferred over the AstraZeneca COVID-19 vaccine for the booster dose, including for people who received the AstraZeneca vaccine for their primary course,” ATAGI said.

“The AstraZeneca vaccine is not yet TGA approved as a booster but can be used as a booster for people who have contraindications to mRNA COVID-19 vaccines or who had AstraZeneca for their primary course.”

The body also said the weight of evidence suggests that booster shots increase antibody levels substantially, likely offering protection against both Delta and the new Omicron variant.

“The anticipated benefits of bringing forward the booster dose include earlier protection, particularly against severe disease in those at risk, and improved protection against COVID-19 due to the Omicron variant,” ATAGI said.

“Vaccine manufacturers have also signalled they are examining the need for and potential development of COVID-19 vaccines that may be more effective against new variants, however this is expected to take several months.”

Updated at 9am AEDT on 13 December 2021.