Analysis of Asymptomatic and Presymptomatic Transmission in SARS-CoV-2 Outbreak, Germany, 2020

Emerg Infect Dis. 2021 Apr;27(4):1159-1163. doi: 10.3201/eid2704.204576. Epub 2021 Feb 18.

Abstract

We determined secondary attack rates (SAR) among close contacts of 59 asymptomatic and symptomatic coronavirus disease case-patients by presymptomatic and symptomatic exposure. We observed no transmission from asymptomatic case-patients and highest SAR through presymptomatic exposure. Rapid quarantine of close contacts with or without symptoms is needed to prevent presymptomatic transmission.

Keywords: COVID-19; Germany; SARS-CoV-2; asymptomatic diseases; contact; coronavirus disease; disease transmission; epidemiology; infectious; respiratory infections; risk; severe acute respiratory syndrome coronavirus 2; viruses; zoonoses.

MeSH terms

  • Adult
  • Asymptomatic Diseases / epidemiology
  • COVID-19* / diagnosis
  • COVID-19* / epidemiology
  • COVID-19* / prevention & control
  • COVID-19* / transmission
  • Contact Tracing* / methods
  • Contact Tracing* / statistics & numerical data
  • Disease Transmission, Infectious* / prevention & control
  • Disease Transmission, Infectious* / statistics & numerical data
  • Female
  • Germany / epidemiology
  • Humans
  • Incidence
  • Male
  • Quarantine* / methods
  • Quarantine* / organization & administration
  • Risk Adjustment
  • SARS-CoV-2 / isolation & purification*
  • Symptom Assessment / methods
  • Symptom Assessment / statistics & numerical data