Margaret Fitzgerald

Comparing two case definitions for including severe acute respiratory infection patients in influenza and COVID-19 vaccine effectiveness studies among older adults using the test-negative design: VEBIS hospital network, seven European countries, 2023/24.

INTRODUCTION Two severe acute respiratory infection (SARI) case definitions (CDs) are often used in test-negative design (TND) hospital-based vaccine effectiveness (VE) studies. SARI-CD1 requires ≥1 symptom (cough, fever, shortness of breath, anosmia, ageusia, or dysgeusia); SARI-CD2 requires both fever and cough. Usin...