Effectiveness of the adapted bivalent mRNA COVID-19 vaccines against hospitalisation in individuals aged ≥ 60 years during the Omicron XBB lineage-predominant period: VEBIS SARI VE network, Europe, February to August, 2023
Liliana Antunes, Clara Mazagatos, Iván Martínez‐Baz, Verónica Gomez, Maria‐Louise Borg, Goranka Petrović, Róisín Duffy, François E. Dufrasne, Ralf Dürrwald, Mihaela Lazăr, Ligita Jančorienė, Beatrix Oroszi, Petr Husa, Jennifer Howard, Aryse Melo, Francisco Pozo, Gloria Pérez‐Gimeno, Jesús Castilla, Ausenda Machado, Aušra Džiugytė, Svjetlana Karabuva, Margaret Fitzgerald, Sébastien Fierens, Kristin Tolksdorf, Odette Popovici, Auksė Mickienė, Gergő Túri, Lenka Součková, Nathalie Nicolay, Angela Rose
Abstract
We conducted a multicentre hospital-based test-negative case-control study to measure the effectiveness of adapted bivalent COVID-19 mRNA vaccines against PCR-confirmed SARS-CoV-2 infection during the Omicron XBB lineage-predominant period in patients aged ≥ 60 years with severe acute respiratory infection from five countries in Europe. Bivalent vaccines provided short-term additional protection compared with those vaccinated > 6 months before the campaign: from 80% (95% CI: 50 to 94) for 14-89 days post-vaccination, 15% (95% CI: -12 to 35) at 90-179 days, and lower to no effect thereafter.