Hybrid, infection- and vaccination-induced protection against laboratory- confirmed SARS-CoV-2 infection in a European multi-centre prospective cohort of healthcare workers, 2021–2024

Hybrid and infection-induced immunity groups were more protected against infection caused by earlier Omicron sub-lineages and more protected than vaccination alone, which had no significant protective effect. These findings highlight the need for adaptive public health strategies, including timely vaccine updates and understanding of prior SARS-CoV-2 infection to inform COVID-19 vaccination policies for HCWs in the post-pandemic era.