Disease severity related to VOC dominance in unvaccinated SARS-CoV-2 positive adults without risk factors in Sweden

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Abstract

Although the emerging SARS-CoV-2 variants of concern (VOC) have shown increasing transmissibility, their role for causing severe disease has not been fully clarified. Here, we studied changes in rates of hospitalisation and severe illness (subjection to high-flow nasal oxygen or admission to an intensive care unit during hospital stay) among all (n=685 891) unvaccinated SARS-CoV-2 positive adults without risk factors in Sweden from November 2020 to September 2021.

After adjustment for age, sex, and socio-economic factors, and with November 2020 (non-VOC period) as reference, the odds ratios (OR) for hospitalisation were 1.6-1.7 in March-May 2021 (Alpha VOC dominance) and 2.4-3.0 in June-September 2021 (Delta VOC dominance), and the ORs for severe illness were 1.8-2.1 in March-May 2021 and 3.1-4.7 in June-September 2021. This study shows that unvaccinated adults without risk factors, have had a gradually increased risk for hospital admission and severe illness when infected with the Alpha and Delta VOCs, respectively.

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  1. SciScore for 10.1101/2021.12.23.21268040: (What is this?)

    Please note, not all rigor criteria are appropriate for all manuscripts.

    Table 1: Rigor

    Ethicsnot detected.
    Sex as a biological variablenot detected.
    Randomizationnot detected.
    Blindingnot detected.
    Power Analysisnot detected.

    Table 2: Resources

    No key resources detected.


    Results from OddPub: We did not detect open data. We also did not detect open code. Researchers are encouraged to share open data when possible (see Nature blog).


    Results from LimitationRecognizer: An explicit section about the limitations of the techniques employed in this study was not found. We encourage authors to address study limitations.

    Results from TrialIdentifier: No clinical trial numbers were referenced.


    Results from Barzooka: We did not find any issues relating to the usage of bar graphs.


    Results from JetFighter: We did not find any issues relating to colormaps.


    Results from rtransparent:
    • Thank you for including a conflict of interest statement. Authors are encouraged to include this statement when submitting to a journal.
    • Thank you for including a funding statement. Authors are encouraged to include this statement when submitting to a journal.
    • No protocol registration statement was detected.

    Results from scite Reference Check: We found no unreliable references.


    About SciScore

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