Inclusion Criteria:  Age between five and eleven years (i.e. prior to the twelfth birthday) at the time of enrolment,  Participant who was randomised in the MIS BAIR trial, and  Was randomly allocated to receive and received BCG as part of the MIS BAIR trial, OR, Was randomly allocated to not receive and did not receive BCG; Is an individual whose parent/legally acceptable representative (LAR) consented to be contacted about future ethically approved research, during the MIS BAIR trial consent process, AND Has a parent/LAR capable of understanding the parent/LAR information statement and consent form (PICF) document and providing consent on the participant's behalf.  Exclusion Criteria:  Has a known hypersensitivity to the active ingredient or any of the excipients in tozinameran, Has a prior polymerase chain reaction (PCR)-confirmed diagnosis of COVID-19 whether symptomatic or not, Has received a COVID-19 vaccine (approved by the TGA or otherwise) prior to trial enrolment, An individual and/or parent/legally acceptable representative who is unwilling or unable to give written informed consent, An individual and/or parent/legally acceptable representative who is unwilling or unable to consent to attend all scheduled study visits, An individual and/or parent/LAR who is unwilling or unable to give consent for blood samples to be taken from the trial participant at each study visit, and Has or has had a clinically significant medical morbidity (e.g. immunocompromised because of congenital or acquired disorders or immunosuppressive medical treatment; a bleeding disorder; a recent history of inflammatory cardiac illness within the past 6 months, e.g., myocarditis, pericarditis, endocarditis, acute rheumatic fever (with active myocardial inflammation) or acute rheumatic heart disease, or acute decompensated heart failure), and Has received BCG at any other time than as part of the MIS BAIR trial.