Fig 1.
PRISMA flow diagram of identified and included studies with reasons for exclusion at the full text stage.
Table 1.
Characteristics of studies reporting proportion of asymptomatic infection among persons positive for COVID-19, by study population (i.e. contacts, general population, and other populations).
No studies were blinded for participants or assessors.
Table 2.
Population characteristics, COVID-19 prevalence, and proportion of asymptomatic infection among COVID-19 positive persons at time of testing.
Table 3.
Studies reporting the proportion of asymptomatic infections among COVID-19 positive persons at the end of follow-up, and time to symptom onset among those developing symptoms.
Table 4.
Pooled estimates of the proportion of asymptomatic infection at initial testing for COVID-19 and proportion asymptomatic at the end of follow-up.
Table 5.
Pooled estimates of secondary attack rates, only high and moderate quality studies.