Fig. 2.

Cumulative incidences of documented COVID-19 (above) and first episode self-reported acute respiratory symptoms or fever (below). COVID-19 is defined as PCR-based or rapid antigen based detection of severe acute respiratory syndrome coronavirus 2 in a respiratory sample in combination with respiratory tract symptoms (cough dyspnoea, nasal cold, sore throat, or loss of smell or taste of any reported severity) or fever (body temperature ≥38.0 °C) in the period 7 days before and up to 14 days after the positive test. Self-reported acute respiratory symptoms are defined as the presence of cough or dyspnoea with a severity score of 2 or higher, or the presence of nasal cold or sore throat with a severity score of 3 or higher. BCG, bacillus Calmette-Guérin.