COVID-19 Vaccine Effectiveness Against Hospitalization in Older Adults, VEBIS Hospital Network, Europe, September 2024-May 2025

We estimated COVID-19 vaccine effectiveness (VE) against PCR-confirmed SARS-CoV-2 hospitalization in patients ≥ 60 years with severe acute respiratory infection, using a multicenter, test-negative, case-control study across seven sites in six European countries between September 2024 and May 2025. We included 352 cases (115 vaccinated; 33%) and 9980 controls (5024 vaccinated; 50%). VE was 42% (95% CI: 15; 61) 14-59 days post-vaccination, 32% (95% CI: -1; 54) at 60-119 days, and 36% (95% CI: 2; 60) at 120-179 days, and no effect thereafter. Among adults aged 60-79 and ≥ 80 years, we observed moderate VE against COVID-19 hospitalization for up to 2 and 4 months, respectively.