We’ve had the third COVID-19 booster rollout. Is a fourth booster on the cards?
At the beginning of November 2021, the Australian Government launched the COVID-19 booster vaccination program, prioritising healthcare workers, residential aged care, and disability facilities. At the time of writing, 50 per cent of the Australian population aged 12 years and over have received a booster dose.
But for those who received their third dose back in November, the question is, what next? Is waning immunity going to be an issue for those who received the booster more than three months ago? Will there be a fourth booster on the horizon for Australians? Where are we at with variant-specific vaccinations and ‘universal’ vaccinations?
Why do we need boosters, and will we need a fourth booster?
Dr Deborah Burnett, Conjoint Senior Lecturer at UNSW’s St Vincent's Clinical School, said data from multiple sources is now emerging that there are two factors at play necessitating the need for booster vaccinations against COVID-19.
“The first is, there is a large body of emerging evidence that although vaccination induces a robust protective antibody response against COVID-19, antibody response wanes over time, decreasing 20-fold from its peak within nine months.
“The second factor at play is because the strains we are now facing are so different from the strain used to formulate the original vaccine, the vaccines themselves are less effective at preventing infection from new variants. While six to 12 months post-second vaccine most people still have antibodies that would protect them against infection with the original strain of SARS-CoV-2 – the virus that causes COVID-19 – only a minority of people have antibodies that would protect them against the infection with the Omicron variant,” explained Dr Burnett.