Investigation and Serologic Follow-Up of Contacts of an Early Confirmed Case-Patient with COVID-19, Washington, USA - Volume 26, Number 8—August 2020 - Emerging Infectious Diseases journal - CDC

Investigation and Serologic Follow-Up of Contacts of an Early Confirmed Case-Patient with COVID-19, Washington, USA - Volume 26, Number 8—August 2020 - Emerging Infectious Diseases journal - CDC

Volume 26, Number 8—August 2020

Synopsis

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

Victoria T. Chu1 , Brandi Freeman-Ponder1, Scott Lindquist, Christopher Spitters, Vance Kawakami, Jonathan W. Dyal, Shauna Clark, Hollianne Bruce, Jeffrey S. Duchin, Chas DeBolt, Sara Podczervinski, Marisa D’Angeli, Kristen Pettrone, Rachael Zacks, Grace Vahey, Michelle L. Holshue, Misty Lang, Rachel M. Burke, Melissa A. Rolfes, Mariel Marlow, Claire M. Midgley, Xiaoyan Lu, Stephen Lindstrom, Aron J. Hall, Alicia M. Fry, Natalie J. Thornburg, Susan I. Gerber, Satish K. Pillai, and Holly M. Biggs

Author affiliations: Centers for Disease Control and Prevention, Atlanta, Georgia, USA (V.T. Chu, B. Freeman-Ponder, J.W. Dyal, Kristen Pettrone, R. Zacks, G. Vahey, M.L. Holshue, R.M. Burke, M.A. Rolfes, M. Marlow, C.M. Midgley, X. Lu, S. Lindstrom, A.J. Hall, A.M. Fry, N.J. Thornburg, S.I. Gerber, S.K. Pillai, H.M. Biggs); Washington State Department of Public Health, Shoreline, Washington, USA (S. Lindquist, C. DeBolt, S. Podczervinski, M. D’Angeli, M.L. Holshue, M. Lang); Snohomish Health District, Everett, Washington, USA (C. Spitters, H. Bruce); Public Health—Seattle and King County, Seattle, Washington (V. Kawakami, S. Clark, J.S. Duchin); University of Washington, Seattle (J.S. Duchin)

Cite This Article

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.

In December 2019, a viral pneumonia outbreak caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan, China, before spreading rapidly to other provinces in China and then internationally (1). On January 20, 2020, the Centers for Disease Control and Prevention (CDC) confirmed a US case of coronavirus disease (COVID-19), the disease caused by SARS-CoV-2, in a traveler who had recently returned to Washington state from Wuhan (2). We investigated contacts of the confirmed case-patient to describe transmission to inform public health recommendations and control measures.