1. Healthy child or adolescent aged 6-17 years (upper age limit is 17 years and 8 months so that both prime and booster are expected to take place prior to their 18th birthday) 2. Able and willing (in the Investigator’s opinion) to comply with all study requirements (participant’s parents/guardians must not rely on public transport or taxis) 3. Willing to allow the investigators to discuss the participant’s medical history with their General Practitioner and access all medical records when relevant to study procedures 4. Parent/guardian to provide informed consent for participants under the age of 16, it will be assumed that participants aged 16 and over are able to provide consent for themselves, however parental support will be sought and investigators will reserve the right to refuse enrollment if concerns arise

1. Healthy child or adolescent aged 6-17 years (upper age limit is 17 years and 8 months so that both prime and booster are expected to take place prior to their 18th birthday) 2. Able and willing (in the Investigator’s opinion) to comply with all study requirements (participant’s parents/guardians must not rely on public transport or taxis) 3. Willing to allow the investigators to discuss the participant’s medical history with their General Practitioner and access all medical records when relevant to study procedures 4. Parent/guardian to provide informed consent for participants under the age of 16, it will be assumed that participants aged 16 and over are able to provide consent for themselves, however parental support will be sought and investigators will reserve the right to refuse enrollment if concerns arise