Investigation and Serologic Follow-Up of Contacts of an Early Confirmed Case-Patient with COVID-19, Washington, USA

Emerg Infect Dis. 2020 Aug;26(8):1671-1678. doi: 10.3201/eid2608.201423. Epub 2020 May 29.

Abstract

We describe the contact investigation for an early confirmed case of coronavirus disease (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), in the United States. Contacts of the case-patient were identified, actively monitored for symptoms, interviewed for a detailed exposure history, and tested for SARS-CoV-2 infection by real-time reverse transcription PCR (rRT-PCR) and ELISA. Fifty contacts were identified and 38 (76%) were interviewed, of whom 11 (29%) reported unprotected face-to-face interaction with the case-patient. Thirty-seven (74%) had respiratory specimens tested by rRT-PCR, and all tested negative. Twenty-three (46%) had ELISA performed on serum samples collected ≈6 weeks after exposure, and none had detectable antibodies to SARS-CoV-2. Among contacts who were tested, no secondary transmission was identified in this investigation, despite unprotected close interactions with the infectious case-patient.

Keywords: 2019 novel coronavirus disease; COVID-19; SARS-CoV-2; contact tracing; coronavirus; coronavirus disease; respiratory infections; serology; severe acute respiratory syndrome coronavirus 2; viruses; zoonoses.

Publication types

  • Case Reports

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Betacoronavirus / genetics
  • Betacoronavirus / pathogenicity*
  • COVID-19
  • COVID-19 Testing
  • Child
  • Child, Preschool
  • Clinical Laboratory Techniques / methods
  • Contact Tracing / statistics & numerical data*
  • Coronavirus Infections / diagnosis
  • Coronavirus Infections / epidemiology*
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Humans
  • Infant
  • Infant, Newborn
  • Male
  • Middle Aged
  • Pandemics*
  • Pneumonia, Viral / diagnosis
  • Pneumonia, Viral / epidemiology*
  • Public Health / methods
  • Reverse Transcriptase Polymerase Chain Reaction
  • SARS-CoV-2
  • Travel
  • Washington / epidemiology