As winter sets in, a new study suggests that receiving a COVID-19 booster at the same time as a flu vaccine could lower coronavirus-related hospital admissions.
Research from the Burnet Institute, published in the Medical Journal of Australia, found that co-administering COVID-19 boosters with the annual flu shot could reduce hospitalisations from COVID-19 by up to 14 per cent.
This comes as health authorities renew efforts to encourage Australians to receive their COVID-19 booster shots, particularly in light of the emerging NB.1.8.1 variant, which has led to a rise in infections.
The NB.1.8.1 variant, now dominant in China and Hong Kong, has been classified by the World Health Organization as a “variant under monitoring.”
Using mathematical modelling, researchers assessed different vaccine rollout timings. Although COVID-19 is not seasonal like the flu, increasing booster uptake by aligning it with the flu vaccination schedule was shown to be a potentially effective public health measure.
Over the past six months, 1.3 million adults aged 18 and over have received COVID-19 booster doses.
Associate Professor Nick Scott, head of modelling and biostatistics at the Burnet Institute and co-author of the study, emphasized the benefits of joint vaccinations.
“COVID-19 causes more hospitalisations and deaths annually than influenza,” he said.
“Co-administering the COVID-19 booster with the flu shot could help match influenza vaccination coverage rates and significantly lower hospital admissions and fatalities.”
In 2023, Australia recorded 62,000 COVID-19 hospitalisations and 3,696 related deaths, compared to 376 deaths from influenza. The flu vaccine currently has 32 per cent annual coverage.
Public health experts continue to advocate for vaccination, especially ahead of flu season.
Fenella McAndrew, another co-author and mathematical modeller, noted that while the timing of COVID-19 vaccinations is less critical, overall uptake is what matters most.
“COVID-19 doesn’t follow a clear seasonal pattern like influenza, so our models show that higher vaccination rates are more beneficial than timing,” she explained.
“The COVID-19 vaccine offers about 85% protection against severe illness, significantly more than the 44% protection the flu vaccine provides against hospitalisation.”
Given its strong efficacy, regular COVID-19 boosters are encouraged as a protective measure.
COVID-19 can have wide-ranging health effects, including damage to the brain, immune system, liver, kidneys, and lungs, and it may raise the risk of cardiovascular issues and diabetes.
The Australian government advises the following COVID-19 booster schedule:
- Healthy adults aged 18–64: every 12 months
- Adults aged 75 and older without risk factors: every 6 months
According to the Department of Health, regular boosters are the best way to stay protected from severe illness, hospitalisation, and death due to COVID-19—especially for people over 65 or those with higher risk factors.
