COVID-19 vaccination and health outcomes
Background
The rollout of the COVID-19 vaccine was launched on 22 February 2021 with a phased approach initially targeting people at highest risk of severe illness and death and highest risk of exposure to the virus (ANAO 2022; Jayasinghe et al. 2023). This included prioritising aged care and disability care residents and workers, frontline health care workers and quarantine and border workers (Department of Health, Disability and Ageing 2021).
By November 2021, 80% of people over the age of 16 in Australia had received 2 doses of the vaccine, at which point there was a staged reopening of international borders and ending of targeted lockdowns (ANAO 2022). The rollout of booster doses began on 8 November 2021 and were initially targeted to people most at risk of severe illness and death with expanded groups included during 2022 (ANAO 2022; Department of Health, Disability and Ageing 2025).
Studies have shown that COVID-19 vaccination is highly effective at reducing the risk of hospitalisation and mortality from COVID-19 among the general population (Albreiki et al. 2023; Liu et al. 2023; Smoll et al. 2023; Katz et al. 2024) and aged care residents (Ellis et al. 2022; Liu et al. 2023; Lu et al. 2024).
This report uses the COVID-19 Register to explore the following among aged care residents diagnosed with COVID-19:
- COVID-19 vaccination status by population groups (to 31 December 2022)
- COVID-19 related hospitalisations (to 30 June 2022) by vaccination status
- Deaths due to COVID-19 (to 31 December 2022) by vaccination status.
Interpreting data on COVID-19 vaccination and health outcomes
COVID-19 vaccination status is based on the number of COVID-19 vaccination doses recorded 14 days or more prior to a COVID-19 diagnosis, to account for a vaccination taking 14 days to become effective (see Technical notes for details). In this report, COVID-19 vaccination status was categorised into residents who were:
- vaccinated (2 or 3 or more doses)
- partially vaccinated (1 dose)
- unvaccinated (0 doses)
- unvaccinated or partially vaccinated (0–1 dose).
Counts were aggregated for 0–1 dose in analyses where the number of residents who had received only one COVID-19 vaccine dose was too low to report separately.
It should be noted that the definitions of vaccination by number of doses have evolved over time based on the rollout of COVID-19 vaccines, so this may not align with current definitions.
It is also important to note that the simple descriptive analyses of COVID-19 vaccination in aged care residents with COVID-19 conducted in this report cannot be used to infer effectiveness of vaccination, for a range of reasons:
- Although findings are presented for aged care residents with and without a dementia record, and by selected breakdowns such as age and sex, they have not been adjusted to account for multiple factors, pre-existing health conditions or other characteristics which may predispose these groups to vaccination, hospitalisation or death.
- People who died during the study period were included in the analysis. People who died, particularly in the oldest age groups, may be more vulnerable and susceptible to hospitalisation than others.
- It is not possible to see when COVID-19 vaccines became available to each residential aged care facility in the COVID-19 Register (ANAO 2022).