These recommendations build upon the initial booster advice provided by ATAGI in February 2023.
The primary focus of these recommendations is to continue reducing the risk of severe illness and death caused by COVID-19, with a particular emphasis on older adults and individuals with risk factors for severe disease. It’s important to note that ATAGI last updated its recommendations regarding a 2023 dose of the COVID-19 vaccine in February 2023.
Recommendations for additional doses
ATAGI recommends that all adults aged 75 years and above should receive an additional COVID-19 vaccine dose in 2023 if at least six months have passed since their last dose. This additional dose is intended to bolster protection for this vulnerable age group.
Additionally, ATAGI advises the following groups to consider an extra COVID-19 booster after consulting with their healthcare provider:
Within these groups, individuals who have no known history of SARS-CoV-2 infection and those with medical comorbidities that increase their risk of severe COVID-19 or who reside in residential aged care facilities are likely to benefit the most from an additional 2023 COVID-19 vaccine dose.
For individuals younger than 75 years and older adults without severe immunocompromise who have already received a dose in 2023, no further doses are currently recommended. Their baseline risk of severe illness remains low if they have been adequately vaccinated and, in some cases, have also gained immunity from prior infection.
Behind the recommendations
ATAGI’s recommendations are grounded in data indicating that older adults, particularly those aged 75 and older, are at the highest risk of severe illness and hospitalisation due to COVID-19.
Recent statistics have shown that the rate of COVID-19-related hospitalisations is significantly higher in individuals aged 75 years and above compared to those aged 65-74.
While COVID-19 vaccines have demonstrated strong protection against severe illness and death over several months, this protection tends to diminish over time.
Studies in Australia have shown that the effectiveness of booster doses in preventing mortality declines from 74.7% within three months to 52.9% after nine months for individuals aged 65 years and above. For those aged 75 and above, effectiveness decreases from 78.3% within three months to 60.5% after nine months. These statistics underscore the importance of timely booster doses, particularly for older adults.
A significant portion of the population has developed ‘hybrid immunity,’ which combines protection from prior vaccinations and previous infections. This hybrid immunity has contributed to lower rates of severe illness among younger individuals compared to older age groups.
As of 1 January 2023, approximately 3.8 million COVID-19 booster doses have been administered to Australians aged 18 and older. Among eligible aged care residents, around 66% have received a booster dose as of August 2023. However, only 53% of individuals aged 65 and older have received a booster dose in the last six months. These figures highlight the importance of encouraging individuals, particularly those in the 65+ age group, to promptly receive COVID-19 booster vaccinations.
ATAGI emphasises the continued preference for bivalent Omicron-based mRNA COVID-19 vaccines for all individuals aged 12 and above. While vaccines based on XBB.1.5 have been developed, they are not yet approved for use in any country, and ATAGI will provide updates as more information becomes available.
The ongoing monitoring of COVID-19 infection rates, clinical outcomes, emerging variants and vaccine effectiveness will inform ATAGI’s future recommendations regarding additional COVID-19 vaccine doses. These guidelines aim to safeguard high-risk individuals and the broader community against the ongoing threat of COVID-19.
Minister for Health and Aged Care Mark Butler said, “For other people who were advised to get a 2023 booster but haven’t had one, it’s not too late to come forward and get one.”
“It is really important people remember Covid-19 is still with us, so I encourage people to keep following the vaccination advice of the experts on the Australian Technical Advisory Group on Immunisation,” he said.