Evaluation of SARS-CoV-2 RNA shedding in clinical specimens and clinical characteristics of 10 patients with COVID-19 in Macau

Int J Biol Sci. 2020 Mar 15;16(10):1698-1707. doi: 10.7150/ijbs.45357. eCollection 2020.


As a city famous for tourism, the public healthcare system of Macau SAR has been under great pressure during the outbreak of the Coronavirus Disease 2019 (COVID-19). In this study, we report clinical and microbiological features of ten COVID-19 patients enrolled in the Centro Hospitalar Conde de São Januário (CHCSJ) between January 21 to February 16, 2020. Clinical samples from all patients including nasopharyngeal swab (NPS)/sputum, urine, and feces were collected for serial virus RNA testing by standard qRT-PCR assay. In total, seven were imported cases and three were local cases. The median duration from Macau arrival to admission in imported cases was 3 days. Four patients required oxygen therapy but none of them needed machinal ventilation. No fatal cases were noted. The most common symptoms were fever (80%) and diarrhea (80%). In the "Severe" group, there was significantly more elderly patients (p=0.045), higher lactate dehydrogenase levels (p=0.002), and elevated C-Reactive protein levels compared to the "Mild to Moderate" group (p<0.001). There were positive SARS-CoV-2 RNA signals in all patients' NPS and stool specimens but negative in all urine specimens. Based on our data on SARS-CoV-2 RNA shedding in stool and the possibility of a lag in viral detection in NPS specimens, the assessment of both fecal and respiratory specimen is recommended to enhance diagnostic sensitivity, and also to aid discharge decision before the role of viral RNA shedding in stool is clarified.

Keywords: COVID-19; Macau; SARS-CoV-2; nasopharyngeal swab; novel coronavirus; qRT-PCR; sputum; stool; urine.

MeSH terms

  • Adult
  • Betacoronavirus*
  • COVID-19
  • COVID-19 Testing
  • COVID-19 Vaccines
  • Clinical Laboratory Techniques
  • Coronavirus Infections / diagnosis*
  • Coronavirus Infections / drug therapy
  • Coronavirus Infections / therapy
  • Coronavirus Infections / virology
  • Diarrhea / virology
  • Feces / virology*
  • Female
  • Fever / virology
  • Humans
  • Lung / diagnostic imaging
  • Macau
  • Male
  • Middle Aged
  • Nasopharynx / virology
  • Pandemics
  • Pneumonia, Viral / diagnosis*
  • Pneumonia, Viral / therapy
  • Pneumonia, Viral / virology
  • RNA, Viral / isolation & purification*
  • Radiography, Thoracic
  • Real-Time Polymerase Chain Reaction
  • Retrospective Studies
  • Reverse Transcriptase Polymerase Chain Reaction
  • SARS-CoV-2
  • Sputum / virology
  • Tomography, X-Ray Computed
  • Urine / virology
  • Virus Shedding*


  • COVID-19 Vaccines
  • Covid-19 aAPC vaccine
  • RNA, Viral

Supplementary concepts

  • COVID-19 drug treatment