{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,29]],"date-time":"2026-10-29T19:03:38Z","timestamp":1793300618178,"version":"4.5.0"},"reference-count":43,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2023,4,14]],"date-time":"2023-04-14T00:00:00Z","timestamp":1681430400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Since the discovery of SARS-CoV-2, changes in genotype and reinfection with different variants have been observed in COVID-19-recovered patients, raising questions around the clinical pattern and severity of primary infection and reinfection. In this systematic review, we summarize the results of 23 studies addressing SARS-CoV-2 reinfections. A total of 23,231 reinfected patients were included, with pooled estimated reinfection rates ranging from 0.1 to 6.8%. Reinfections were more prevalent during the Omicron variant period. The mean age of reinfected patients was 38.0 \u00b1 6. years and females were predominant among reinfected patients (M\/F = 0.8). The most common symptoms during the first and second infection were fever (41.1%), cough (35.7% and 44.6%), myalgia (34.5% and 33.3%), fatigue (23.8% and 25.6%), and headaches (24.4% and 21.4%). No significant differences of clinical pattern were observed between primary infection and reinfection. No significant differences in the severity of infection were observed between primary infection and reinfection. Being female, being a patient with comorbidities, lacking anti-nucleocapsid IgG after the first infection, being infected during the Delta and Omicron wave, and being unvaccinated were associated with a higher risk of reinfection. Conflicting age-related findings were found in two studies. Reinfection with SARS-CoV-2 suggests that natural immunity is not long-lasting in COVID-19 patients.<\/jats:p>","DOI":"10.3390\/v15040967","type":"journal-article","created":{"date-parts":[[2023,4,14]],"date-time":"2023-04-14T10:29:16Z","timestamp":1681468156000},"page":"967","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":76,"title":["SARS-CoV-2 Reinfection and Severity of the Disease: A Systematic Review and Meta-Analysis"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4126-9167","authenticated-orcid":false,"given":"Nhu Ngoc","family":"Nguyen","sequence":"first","affiliation":[{"name":"Aix Marseille Univ, IRD, AP-HM, SSA, VITROME, Marseille, France"},{"name":"IHU-M\u00e9diterran\u00e9e Infection, Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Y Ngoc","family":"Nguyen","sequence":"additional","affiliation":[{"name":"Hoan My Sai Gon Hospital, Ho Chi Minh City, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1369-8615","authenticated-orcid":false,"given":"Van Thuan","family":"Hoang","sequence":"additional","affiliation":[{"name":"Thai Binh University of Medicine and Pharmacy, Thai Binh, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5556-6947","authenticated-orcid":false,"given":"Matthieu","family":"Million","sequence":"additional","affiliation":[{"name":"IHU-M\u00e9diterran\u00e9e Infection, Marseille, France"},{"name":"Aix Marseille Univ, IRD, AP-HM, MEPHI, Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Philippe","family":"Gautret","sequence":"additional","affiliation":[{"name":"Aix Marseille Univ, IRD, AP-HM, SSA, VITROME, Marseille, France"},{"name":"IHU-M\u00e9diterran\u00e9e Infection, Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,14]]},"reference":[{"key":"ref_1","unstructured":"Word Health Organization (WHO) (2022, June 25).  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