COVID-19 vaccine effectiveness monitoring in Australia

Vaccine effectiveness is a measure of vaccine performance in the population usually estimated after the vaccine has been registered and is being used. With continuing evolution of SARS-CoV-2 and new variant-specific vaccines, as well as changes in uptake of vaccination and incidence of infections in the population, continued assessment of COVID-19 vaccine effectiveness is important to inform programmatic and policy decisions. In Australia, COVID-19 vaccine effectiveness against mortality has been assessed regularly using whole of population health data. These analyses have shown how vaccine boosting with the most up to date variant vaccines has been highly effective in reducing COVID-19 deaths in older adults. However, waning of protection continues to be observed supporting the need for regular boosters in older Australian adults and the need to continue to monitor the effectiveness of the COVID-19 vaccine program.