Study #1: COVID-19 vaccine effectiveness against hospitalisation

This study uses a multi-country hospital-based test negative case control design. Patient recruitment was initiated in September 2021 and by December 2023, over 10,237 patients were recruited across 17 hospitals in 5 European countries.

The study was initiated on request by Astrazeneca and Janssen and was later joined by Novavax, Valneva and Pfizer to fulfil regulatory commitments. The data collection is still ongoing.

The first results on AstraZeneca’s COVID-19 vaccine were published in Lancet Regional Health Europe (

Hospitals recruiting for the COVID-19 Vaccine Effectiveness study

Study #2: Respiratory surveillance study

This is a multi-country hospital-based study that will start in June 2024.