Effectiveness of 2024/25 KP.2 vaccine against outpatient COVID-19 in Canada

Between November 2024 and April 2025, the Canadian Sentinel Practitioner Surveillance Network assessed KP.2 vaccine effectiveness against outpatient COVID-19 by test-negative design. Vaccination protected best during the first two months, reducing risk by two-thirds among vaccinated versus unvaccinated individuals, declining by 3-4 months, and reducing the risk overall by half.
Epistemonikos ID: c36f22577e0989db2a85a928ed69366992cbd67e
First added on: Sep 24, 2025