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Cited by 533

The DOI matches its Crossref record; 58 of the 58 references it cites were found in a registry or an index.

The Proportion of SARS-CoV-2 Infections That Are Asymptomatic: A Systematic Review

Open access
Oran, Daniel P., Topol, Eric J.·2021·Annals of Internal Medicine

Abstract

BACKGROUND: Asymptomatic infection seems to be a notable feature of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the pathogen that causes coronavirus disease 2019 (COVID-19), but the prevalence is uncertain. PURPOSE: To estimate the proportion of persons infected with SARS-CoV-2 who never develop symptoms. DATA SOURCES: . STUDY SELECTION: Observational, descriptive studies and reports of mass screening for SARS-CoV-2 that were either cross-sectional or longitudinal in design; were published through 17 November 2020; and involved SARS-CoV-2 nucleic acid or antibody testing of a target population, regardless of current symptomatic status, over a defined period. DATA EXTRACTION: The authors collaboratively extracted data on the study design, type of testing performed, number of participants, criteria for determining symptomatic status, testing results, and setting. DATA SYNTHESIS: = 61 075), which suggest that at least one third of SARS-CoV-2 infections are asymptomatic. LIMITATION: For PCR-based studies, data are limited to distinguish presymptomatic from asymptomatic infection. Heterogeneity precluded formal quantitative syntheses. CONCLUSION: Available data suggest that at least one third of SARS-CoV-2 infections are asymptomatic. Longitudinal studies suggest that nearly three quarters of persons who receive a positive PCR test result but have no symptoms at the time of testing will remain asymptomatic. Control strategies for COVID-19 should be altered, taking into account the prevalence and transmission risk of asymptomatic SARS-CoV-2 infection. PRIMARY FUNDING SOURCE: National Institutes of Health.

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Metadata

Authors
Oran, D. P., & Topol, E. J.
Venue
Annals of Internal Medicine
Published
2021-05
Volume
174
Issue
5
Pages
655-662
ISSN
  • 0003-4819 (ISSN-L)
  • 1539-3704
OpenAlex
W3122838760
Cited by
533
References
58
FWCI
36.94
Type
journal article
Language
en
Open access
green

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CoChat. (2026). Citation check: The Proportion of SARS-CoV-2 Infections That Are Asymptomatic: A Systematic Review. https://app.cochat.ai/papers/10.7326/m20-6976
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Oran, D. P., & Topol, E. J. (2021). The Proportion of SARS-CoV-2 Infections That Are Asymptomatic: A Systematic Review. Annals of Internal Medicine. https://doi.org/10.7326/m20-6976

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