1. To assess the local reactogenicity profile and tolerability of ChAdOx1 nCoV (5.0 x1010vp /5.0 x1010vp) given as a homologous prime boost schedules (28 and 84 days interval post prime) in children aged 6-17 years 1.1. Occurrence of solicited local reactogenicity signs and symptoms for 7 days following vaccination 1.2. Occurrence of solicited systemic reactogenicity signs and symptoms for 7 days following vaccination 2. To determine the safety of the candidate ChAdOx1 nCoV-19 in children aged 6 - 17 years 2.1. Occurrence of unsolicited adverse events (AEs) for 28 days following vaccination 2.2. Occurrence of SAEs and disease enhancement episodes over course of study 2.3. Occurrence of serious adverse events (SAEs) throughout study duration

1. To assess the local reactogenicity profile and tolerability of ChAdOx1 nCoV (5.0 x1010vp /5.0 x1010vp) given as a homologous prime boost schedules (28 and 84 days interval post prime) in children aged 6-17 years 1.1. Occurrence of solicited local reactogenicity signs and symptoms for 7 days following vaccination 1.2. Occurrence of solicited systemic reactogenicity signs and symptoms for 7 days following vaccination 2. To determine the safety of the candidate ChAdOx1 nCoV-19 in children aged 6 - 17 years 2.1. Occurrence of unsolicited adverse events (AEs) for 28 days following vaccination 2.2. Occurrence of SAEs and disease enhancement episodes over course of study 2.3. Occurrence of serious adverse events (SAEs) throughout study duration