A Systematic Review on the Recurrence of Sars-Cov-2 Virus: Frequency, Risk Factors, and Possible Explanations Publisher Pubmed



Piri SM¹ ; Edalatfar M¹ ; Shool S² ; Jalalian MN³ ; Tavakolpour S^{4, 5}
Source: Infectious Diseases Published:2021

Abstract

Background: Since late 2019, SARS-CoV-2 which leads to coronavirus disease 2019 (COVID-19), has caused thousands of deaths. There are some pieces of evidence that SARS-CoV-2 genome could be re-detectable in recovered patients. Methods: We performed a systematic review in the PubMed/Medline database to address the risk of SARS-CoV-2 recurrence. The last update was for 20 November 2020. Among the 1178 initially found articles, 66 met the inclusion criteria and were considered. Findings: In total, 1128 patients with at least one-time recurrence of SARS-CoV-2 were included. Recurrence rate has been reported between 2.3% and 21.4% in cohort studies, within a mean of 20 (ranged 1–98) days after discharge; younger patients are being affected more. Following the second course of disease, the disease severity decreased or remained unchanged in 97.3% while it increased in 2.6%. Anti-SARS-CoV-2 IgG and IgM were positive in 11–95% and 58.8–100%, respectively. Based on the literature, three possibilities include reactivation of previous disease, reinfection with the same virus, and false negative, which have been discussed in details. Conclusion: There is a relatively notable risk of disease recurrence in previously recovered patients, even those who are immunised against the virus. More studies are required to clarify the underlying cause of this phenomenon. © 2021 Society for Scandinavian Journal of Infectious Diseases.