November 3, 2020

SARS-CoV-2 Seroprevalence and Transmission Risk Factors among High-Risk Close Contacts: A Retrospective Cohort Study

Category: Article Summary

Topic: Transmission

Keywords (Tags): transmission

A retrospective cohort study of all close contacts of confirmed COVID-19 cases in Singapore (n=7,770) found the attack rate among household contacts (5.9%) was higher compared to work contacts and social contacts (both 1.3%). Among contacts, close physical proximity (sharing a bedroom for household contacts and sharing a vehicle for work and social contacts) and verbal interactions 30 minutes or longer were associated with SARS-CoV-2 transmission. Findings further estimate that a symptom-based PCR-testing strategy missed 62% of COVID-19 diagnoses, and that 36% of individuals with SARS-CoV-2 infection were asymptomatic.

Ng et al. (Nov 2, 2020). SARS-CoV-2 Seroprevalence and Transmission Risk Factors among High-Risk Close Contacts: A Retrospective Cohort Study. The Lancet Infectious Diseases. https://doi.org/10.1016/S1473-3099(20)30833-1