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. 2021 Jul 16;21(1):688.
doi: 10.1186/s12879-021-06376-1.

COVID-19 viral load not associated with disease severity: findings from a retrospective cohort study

Abdulkarim Abdulrahman  1   2 , Saad I Mallah  3 , Manaf Alqahtani  4   5   6
Affiliations

COVID-19 viral load not associated with disease severity: findings from a retrospective cohort study

Abdulkarim Abdulrahman et al. BMC Infect Dis. .

Abstract

Background: Being able to use COVID-19 RT-PCR Ct values as simple clinical markers of disease outcome or prognosis would allow for the easy and proactive identification and triaging of high-risk cases. This study's objective was thus to explore whether a correlation exists between COVID-19 viral loads, as indicated by RT-PCR Ct values, and disease severity, as indicated by respiratory indices.

Results: A multi-centre cross-sectional retrospective study was conducted, using data obtained from Bahrain's National COVID-19 Task force's centralised database. The study period ranged from May 2, 2020 to July 31, 2020. A multivariable logistic regression was used to assess for a correlation using data from a total of 1057 admitted COVID-19 cases. The covariates adjusted for included sex, age, presentation, and comorbidities. In our cohort, Ct value showed no statistical significance for an association with requirement for oxygenation on admission (Odds ratio 1.046; 95%CI 0.999 to 1.096, p = 0.054).

Conclusion: Viral load, as indicated by Ct values, did not seem to be associated with requirement for oxygenation on admission in our cohort. We postulate however that time since onset of symptom may have acted as an unaccounted-for confounder. As such, RT-PCR Ct values may not be a useful prognostic clinical tool in isolation.

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Conflict of interest statement

None declared.

Figures

Fig. 1
Fig. 1
Boxplot of Ct Values by disease severity on admission
Fig. 2
Fig. 2
Percentage of Patients on Room Air, Supplemental Oxygen, and NIV/HFNC as per Ct Value Categories
See this image and copyright information in PMC

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