Clin Microbiol Infect. 2020 Jul 22:S1198-743X(20)30427-4. doi: 10.1016/j.cmi.2020.07.020. Online ahead of print.
OBJECTIVES: To determine whether various clinical specimens obtained from COVID-19 patients contain the infectious virus.
METHODS: To demonstrate whether various clinical specimens contain the viable virus, we collected naso/oropharyngeal swabs, saliva, urine, and stool from five COVID-19 patients and performed a quantitative polymerase chain reaction (qPCR) to assess viral load. Specimens positive by qPCR were subjected to virus isolation in Vero cells. We also used urine and stool samples to intranasally inoculate ferrets and evaluated the virus titers in nasal washes on 2, 4, 6, and 8 days post-infection (dpi).
RESULTS: SARS-CoV-2 RNAs were detected in all naso/oropharyngeal swabs, saliva, urine, and stool samples collected between days 8 to 30 of the clinical course. Notably, viral loads in urine, saliva, and stool samples were almost equal to or higher than those in naso/oropharyngeal swabs (urine 1.08±0.16 - 2.09±0.85 log10 copies/ml, saliva 1.07±0.34 - 1.65±0.46 log10 copies/ml, stool 1.17±0.32 log10 copies/ml, naso/oropharyngeal swabs 1.18±0.12 - 1.34±0.30 log10 copies/ml). Further, viable SARS-CoV-2 was isolated from naso/oropharyngeal swabs and saliva of COVID-19 patients, as well as nasal washes of ferrets inoculated with patient urine or stool.
CONCLUSIONS: Viable SARS-CoV-2 was demonstrated in saliva, urine, and stool from COVID-19 patients up until days 11 to 15 of the clinical course. This result suggests that viable SARS-CoV-2 can be secreted in various clinical samples as well as respiratory specimens.