Symptomatic SARS-CoV-2 infection (COVID-19)
ASYMPTOMATIC SARS-COV-2 INFECTION
Symptomatic SARS-CoV-2 infection (COVID-19) was defined as the incidence of the first occurrence of symptomatic SARS-CoV-2 infection measured by RT–PCR of nasal swabs starting 14 days after the booster dose. Surveillance for COVID-19 symptoms is conducted via weekly contact and blood draw, and an illness visit to collect a nasopharyngeal swab was arranged for participants reporting COVID-19 symptoms.Two definitions of symptomatic SARS-CoV-2 infection (COVID-19) were used including the primary case definition in the COVE trialThe date of a documented COVID-19 case was the later date of a symptom and the date of a positive RT–PCR test, and the two dates were to be within 14 days of each other. The time to the first occurrence of COVID-19 is calculated as the date of documented COVID-19 minus the date of injection +1. Cases are counted starting 14 days after the injection (date of documented COVID-19 minus date of the injection ≥14).All analyses were conducted using SAS v.9.4 or higher.