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The Mouth as a Reservoir of SARS-CoV-2

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Abstract

Purpose of Review

This systematic review addresses the question: Is the oral cavity a reservoir of SARS-CoV-2 in participants who tested positive for viral RNA in nasopharyngeal and oropharyngeal samples? Four databases and a complementary search on the reference list of included studies were consulted. Paired reviewers independently searched the literature, extracted data, and evaluated the risk of bias (Joanna Briggs Institute).

Recent Findings

A total of 3173 references were identified, and after a 2-phase selection, 24 studies were included. In total, 10 diagnostic test accuracy and 14 cross-sectional studies determined the presence of SARS-CoV-2 using real-time quantitative polymerase chain reaction (RT-qPCR) incorporating experimental and control samples. It was shown that saliva, gingival crevicular fluid, dental plaque, and gingival tissue harbored viral RNA. A high level of heterogenicity between studies was observed. The risk of bias analysis raised major concerns regarding the lack of clear criteria for inclusion, with most studies being of moderate to low quality. SARS-CoV-2 RNA is present in oral cavity samples, reinforcing the contribution of the oral cavity as a potential route of entry for infection and may offer a practical and affordable point-of-care platform for COVID-19 diagnosis. Furthermore, comprehending the oral cavity as a reservoir of SARS-CoV-2 may provide insight into its persistence and transmissibility.

Summary

The oral cavity can serve as a reservoir of SARS-CoV-2. Awareness of the significance of the oral cavity as a SARS-CoV-2 viral reservoir may help to shape COVID-19 containment measures and further potential therapeutic initiatives.

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Authors and Affiliations

  1. Dental Faculty, Federal University of Rio Grande Do Sul, Rua Ramiro Barcelos, Bairro Santa Cecília, Porto Alegre, 2492, Brazil

    Sabrina Carvalho Gomes

  2. Dental Faculty, Federal University of Rio Grande Do Sul, Porto Alegre, Brazil

    Luisa Martins Miller

  3. Dental Faculty, Federal University of Rio Grande Do Sul, Porto Alegre, Brazil

    Luana Xavier

  4. Section for Oral Ecology and Inflammation, Department of Dentistry and Oral Health, Aarhus University, Aarhus, Denmark

    Fernando Valentim Bitencourt

  5. Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus, Denmark

    Fernando Valentim Bitencourt

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  1. Sabrina Carvalho Gomes
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  4. Fernando Valentim Bitencourt
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Contributions

SCG was the study coordinator and took part in all stages of the manuscript, except for the selection of studies. FVB and LM did this and helped write the manuscript. LX helped with data extraction. All authors worked editing the final version of the manuscript.

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Correspondence to Sabrina Carvalho Gomes.

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Gomes, S.C., Miller, L.M., Xavier, L. et al. The Mouth as a Reservoir of SARS-CoV-2. Curr Oral Health Rep 11, 144–166 (2024). https://doi.org/10.1007/s40496-024-00369-0

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