This will be open-label, single-arm implementation study in Eswatini. All individuals who register on the National Vaccination Registry will be eligible for enrolment. Participants will receive appointments for vaccination using the registry. Vaccination will be overseen by trained personnel. At enrolment participants will receive an intramuscular injection of AZ1222, a second dose will be given 10 weeks after the first injection. Surveillance for vaccine effectiveness will be performed at designated hospitals.
A prospective hospital-based, case-control study with test-negative controls (test-negative case-control design) and optionally other hospital controls (standard case-control design) will be conducted in parallel with the implementation study. Data will be collected through a network of hospitals located in Eswatini. A hospital-based case control study is an efficient design well suited to study for effectiveness against severe disease, and potentially allows for detailed medical information and additional data collection directly from the patient or healthcare provider. In addition, the study aims to determine the vaccine effectiveness (VE) of AZ1222 against severe disease due to the B.1.351 variant circulating in Southern Africa and other new variants that might evolve.
