Detectable 2019-nCoV viral RNA in blood is a strong indicator for the further clinical severity

Emerg Microbes Infect. 2020 Feb 26;9(1):469-473. doi: 10.1080/22221751.2020.1732837. eCollection 2020.


The novel coronavirus (2019-nCoV) infection caused pneumonia. we retrospectively analyzed the virus presence in the pharyngeal swab, blood, and the anal swab detected by real-time PCR in the clinical lab. Unexpectedly, the 2109-nCoV RNA was readily detected in the blood (6 of 57 patients) and the anal swabs (11 of 28 patients). Importantly, all of the 6 patients with detectable viral RNA in the blood cohort progressed to severe symptom stage, indicating a strong correlation of serum viral RNA with the disease severity (p-value = 0.0001). Meanwhile, 8 of the 11 patients with annal swab virus-positive was in severe clinical stage. However, the concentration of viral RNA in the anal swab (Ct value = 24 + 39) was higher than in the blood (Ct value = 34 + 39) from patient 2, suggesting that the virus might replicate in the digestive tract. Altogether, our results confirmed the presence of virus RNA in extra-pulmonary sites.

Keywords: 2019-ncov; anal swab; blood viral RNA; laboratory test; pharyngeal swab.

Publication types

  • Letter

MeSH terms

  • Betacoronavirus / genetics
  • Betacoronavirus / isolation & purification*
  • COVID-19
  • COVID-19 Testing
  • Clinical Laboratory Techniques
  • Coronavirus Infections / blood
  • Coronavirus Infections / diagnosis
  • Coronavirus Infections / virology*
  • Humans
  • Pneumonia, Viral
  • RNA, Viral / blood*
  • RNA, Viral / genetics
  • Real-Time Polymerase Chain Reaction
  • Retrospective Studies
  • SARS-CoV-2
  • Severity of Illness Index


  • RNA, Viral

Grants and funding

We declare no competing interest. We thank all the physicians and nurses who cared these patients. This work was supported by National Natural Science Foundation of China Grant (No. 81670536 and 81770593) and by the National Science and Technology Major Project (2017ZX10202203-004-002).