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The association between nasopharyngeal (NP) SARS-CoV-2 viral loads and clinical outcomes remains debated. Here, we examined the factors that might predict the NP viral load and the role of the viral load as a predictor of clinical outcomes. A convenience sample of 955 positive remnant NP swab eluent samples collected during routine care between 18 November 2020 and 26 September 2021 was cataloged and a chart review was performed. For non-duplicate samples with available demographic and clinical data (i.e., non-employees), an aliquot of eluent was sent for a droplet digital PCR quantification of the SARS-CoV-2 viral load. Univariate and multivariate analyses were performed to identify the clinical predictors of NP viral loads and the predictors of COVID-19-related clinical outcomes. Samples and data from 698 individuals were included in the final analysis. The sample cohort had a mean age of 50 years (range: 19–91); 86.6% were male and 76.3% were unvaccinated. The NP viral load was higher in people with respiratory symptoms (p = 0.0004) and fevers (p = 0.0006). In the predictive models for the clinical outcomes, the NP viral load approached a significance as a predictor for in-hospital mortality. In conclusion, the NP viral load did not appear to be a strong predictor of moderate-to-severe disease in the pre-Delta and Delta phases of the pandemic, but was predictive of symptomatic diseases and approached a significance for in-hospital mortality, providing support to the thesis that early viral control prevents the progression of disease. [ABSTRACT FROM AUTHOR]

Our study aimed to investigate the kinetics of SARS-CoV-2 RNA in bile and in different body fluids of two SARS-CoV-2 positive patients with acute cholecystitis by innovative droplet digital PCR (ddPCR) assays. For each patient, nasopharyngeal- and rectal swabs, bile, urine, and plasma samples were collected at different time points for SARS-CoV-2 RNA quantification by two ddPCR assays. For both patients, ddPCR revealed persistent and prolonged detection of viral RNA in the nasopharyngeal swab despite triple-negative or single-positive results by qRT-PCR. In Patient 1, SARS-CoV-2 RNA dropped more rapidly in bile and rectal-swab and declined slowly in nasopharyngeal swab and plasma, becoming undetectable in all compartments 97 days after symptoms started. Conversely, in patient 2, SARS-CoV-2 RNA was detected, even if at low copies, in all body samples (with the exception of urine) up to 75 days after the onset of symptoms. This study highlights that SARS-CoV-2 RNA can persist for a prolonged time in respiratory samples and in several biological samples despite negativity to qRT-PCR, supporting SARS-CoV-2's ability to provoke persistent and disseminated infection and therefore to contribute to extra-pulmonary clinical manifestations. [ABSTRACT FROM AUTHOR]