A person is not eligible if they: 1. Are contraindicated to receive any study COVID-19 booster vaccine per Australian guidelines. E.g. have a history of anaphylaxis to a vaccine component or myocarditis attributed to previous receipt of a messenger ribonucleic acid (mRNA) vaccine. 2. Are immunocompromised or have known immunodeficiency.

A person is not eligible if they: 1. Are contraindicated to receive any study COVID-19 booster vaccine per Australian guidelines. E.g. have a history of anaphylaxis to a vaccine component or myocarditis attributed to previous receipt of a messenger ribonucleic acid (mRNA) vaccine. 2. Are immunocompromised or have known immunodeficiency.