Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread rapidly throughout the world since the first cases of coronavirus disease 2019 (COVID-19) were observed in December 2019 in Wuhan, China. It has been suspected that infected persons who remain asymptomatic play a significant role in the ongoing pandemic, but their relative number and effect have been uncertain. The authors sought to review and synthesize the available evidence on asymptomatic SARS-CoV-2 infection. Asymptomatic persons seem to account for approximately 40% to 45% of SARS-CoV-2 infections, and they can transmit the virus to others for an extended period, perhaps longer than 14 days. Asymptomatic infection may be associated with subclinical lung abnormalities, as detected by computed tomography. Because of the high risk for silent spread by asymptomatic persons, it is imperative that testing programs include those without symptoms. To supplement conventional diagnostic testing, which is constrained by capacity, cost, and its one-off nature, innovative tactics for public health surveillance, such as crowdsourcing digital wearable data and monitoring sewage sludge, might be helpful.
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Author, Article and Disclosure Information
Disclosures: Authors have disclosed no conflicts of interest. Forms can be viewed at www.acponline.org/authors/icmje/ConflictOfInterestForms.do?msNum=M20-3012.
Corresponding Author: Eric J. Topol, MD, Scripps Research Translational Institute, 3344 North Torrey Pines Court, 3rd Floor, La Jolla, CA 92037; e-mail, [email protected]
Correction: This article was corrected on 17 June 2020 to update the publication and access dates for reference 12.
Current Author Addresses: Mr. Oran and Dr. Topol: Scripps Research Translational Institute, 3344 North Torrey Pines Court, 3rd Floor, La Jolla, CA 92037.
Author Contributions: Conception and design: D.P. Oran, E.J. Topol.
Analysis and interpretation of the data: D.P. Oran, E.J. Topol.
Drafting of the article: D.P. Oran, E.J. Topol.
Critical revision of the article for important intellectual content: E.J. Topol.
Final approval of the article: D.P. Oran, E.J. Topol.
Statistical expertise: E.J. Topol.
Administrative, technical, or logistic support: E.J. Topol.
Collection and assembly of data: D.P. Oran, E.J. Topol.
This article was published at Annals.org on 3 June 2020.
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