Less than half of all double-vaccinated Australians aged 18 and over have had their COVID-19 booster shot, new analysis from The Australian National University (ANU) shows.
A survey of more than 3,400 adults, conducted in January 2022, found just over four-in-10 Australians (41.5 per cent) have received a third dose of a COVID vaccine.
"There is a very large proportion of adult Australians who are eligible for a booster but have not yet done so, with many of these individuals likely to have waning immunity from their first two doses," study co-author Professor Nicholas Biddle said.
The survey shows a greater number of respondents are more hesitant to receive a booster shot now than they were in October 2021, highlighting a shift in attitude towards the booster in recent months.
"In January 2022 a very high proportion of people, 65.4 per cent, said they would definitely have the booster," Professor Biddle said.
"This is a little lower than when the same people were asked in October 2021, when 71.9 per cent of people said they'd get a booster.
"Leaving aside those who are not eligible, for some others this may reflect a belief that they are sufficiently protected from their initial two doses.
"The experience of the first two doses, particularly side effects, may also have made some reluctant to seek out a third dose."
The survey also found young Australians aged 18-24, Aboriginal and Torres Strait Islander Australians, those with low education, and people who live in disadvantaged areas are less likely to have received a third dose of a COVID vaccine.
Professor Biddle said a lack of information and disengagement from any form of information around COVID-19 is responsible for the low booster uptake among these groups, and it is not due to vaccine misinformation or resistance to the jab.
"The findings suggest that booster uptake is not due to active resistance to government policy or recommendations, but rather because people either do not have that much information about the need for a third dose or because they have made a judgement that it is not necessary for them," he said.
"Despite success at the national level in terms of the vaccine roll-out, there are still groups that are under-vaccinated and there is no guarantee that the first and second dose success will be replicated with the third dose.
"We found those who have not completed Year 12 are significantly less likely to have received a booster compared to those who have completed Year 12 or have received post-school qualifications.
"We also see that Australians in the top income quintile are more likely to have received their booster compared to lower income earners, showing that socioeconomic status clearly matters."
Although the number of boosters administered in Australia is lower than the likes of the United Kingdom (UK) - 55.5 boosters per 100 people have been administered in the UK compared to 40-45 doses administered per 100 people in Australia - as of mid-February there has been an encouraging shift in booster uptake across Australia.
"While the number of boosters administered in Canada and the United Kingdom appear to be levelling off, the number of third-dose jabs administered in Australia and New Zealand continues to rise as of 15 February," Professor Biddle said.
The study has been conducted by the Social Research Centre on behalf of the ANU Centre for Social Research and Methods.