Early Risk Factors for the Duration of Severe Acute Respiratory Syndrome Coronavirus 2 Viral Positivity in Patients With Coronavirus Disease 2019

Clin Infect Dis. 2020 Nov 19;71(16):2061-2065. doi: 10.1093/cid/ciaa490.


Background: Pneumonia coronavirus disease 2019 (COVID-19) has became a pandemic. However, information on early risk factors for the duration of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral positivity is not yet available.

Methods: In this prospective study, a cohort of 137 patients with confirmed SARS-CoV-2 were enrolled. Clinical information and laboratory data were retrieved from electronic medical records. Viral positivity duration was calculated by the interval from the day of confirmed SARS-CoV-2 positive results to the day SARS-CoV-2 testing showed negative results in these 137 patients with COVID-19. Early risk factors for the duration of SARS-CoV-2 viral positivity were evaluated.

Results: The median SARS-CoV-2 viral positivity duration is 12 days (range, 4 to ~45) for this cohort. Cox regression results showed a significantly shorter viral positivity duration was related to younger age (hazard ratio [HR], .658; P = .017); disease not being severe (HR, .653; P = .076); higher lymphocyte (HR, 1.464; P = .033), eosinophil (HR, 1.514; P = .020), and CD8+ T-cell (HR, 1.745; P = .033) counts; and lower IL-6 (HR, .664; P = .036) and IL-10 (HR, .631; P = .021). Multivariate analysis with covariable-adjusted results showed that the CD8+ T-cell count (HR, 2.376; P= .114) was a predominant risk factor for the duration of SARS-CoV-2 viral positivity.

Conclusions: Our findings show early laboratory parameters such as CD8+ T-cell count to be risk factors for the duration of SARS-CoV-2 viral positivity, which has significance in the control and prevention of the disease.

Keywords: COVID-19; SARS-CoV-2; risk factors; viral positivity duration.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • COVID-19 / epidemiology*
  • COVID-19 / pathology*
  • COVID-19 / virology
  • Child
  • Child, Preschool
  • Coronavirus / pathogenicity*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Risk Factors
  • SARS-CoV-2 / pathogenicity*
  • Young Adult