Early COVID‐19 XBB.1.5 Vaccine Effectiveness Against Hospitalisation Among Adults Targeted for Vaccination, VEBIS Hospital Network, Europe, October 2023–January 2024.

We conducted a multicentre test‐negative case–control study covering the period from October 2023 to January 2024 among adult patients aged ≥ 18 years hospitalised with severe acute respiratory infection in Europe. We provide early estimates of the effectiveness of the newly adapted XBB.1.5 COVID‐19 vaccines against PCR‐confirmed SARS‐CoV‐2 hospitalisation. Vaccine effectiveness was 49% overall, ranging between 69% at 14–29 days and 40% at 60–105 days post vaccination. The adapted XBB.1.5 COVID‐19 vaccines conferred protection against COVID‐19 hospitalisation in the first 3.5 months post vaccination, with VE > 70% in older adults (≥ 65 years) up to 1 month post vaccination. [ABSTRACT FROM AUTHOR]