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The Proportion of Asymptomatic Cases Among SARS-CoV-2 Infected Patients: A Systematic Review
European Journal of Clinical and Biomedical Sciences
Volume 6, Issue 5, October 2020, Pages: 84-89
Received: Aug. 4, 2020; Accepted: Aug. 21, 2020; Published: Sep. 7, 2020
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Abdi Birhanu, School of Medicine, Haramaya University, Harar, Ethiopia
Teka Obsa Feyisa, School of Medicine, Haramaya University, Harar, Ethiopia
Getahun Chala, School of Medicine, Haramaya University, Harar, Ethiopia
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Even though some reports unveiled that coronavirus 2019 (COVID-19) cases can be manifested as asymptomatic, there is limited information on how much these cases are significant. Understanding the possible proportion of asymptomatic cases among confirmed patients might help in re-considering of who should be tested for the SARS-CoV-2 infection. Therefore, this study was aimed to summarize the proportion of asymptomatic cases among SARS-COV-2 infected people since the outbreak of COVID-19. Methods: Different studies were searched from databases (PubMed, Medline) by using searching terms. Finally, all eligible articles were selected by using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2009 flow diagram. Results: A total of 14 articles that reported asymptomatic cases of COVID-19 were included in this systematic review. The sample size of the studies was ranged from 8 to 2143. Out of the total cases, the overall proportion of asymptomatic cases was 25.9% that ranged from 3.23% to 78%. This systematic review also summarized that there was 17. 6%, 4.8%, and 3.23% to 62.2% of asymptomatic cases among pregnant mothers, children, and the adult general population, respectively. Conclusion and Remarks: This review showed that the proportion of asymptomatic SARS-CoV-2 infected people is high. Hence, to tackle COVID-19, all concerned bodies should strengthen the screening of asymptomatic cases as part of contact tracing efforts.
Asymptomatic Cases, COVID-19, Proportion, SARS-COV-2, Systematic Review
To cite this article
Abdi Birhanu, Teka Obsa Feyisa, Getahun Chala, The Proportion of Asymptomatic Cases Among SARS-CoV-2 Infected Patients: A Systematic Review, European Journal of Clinical and Biomedical Sciences. Vol. 6, No. 5, 2020, pp. 84-89. doi: 10.11648/j.ejcbs.20200605.13
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This article is an open access article distributed under the Creative Commons Attribution License ( which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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