Viable SARS-CoV-2 in various specimens from COVID-19 patients

Abstract

Objectives The aim was 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 and saliva, urine and stool samples from five COVID-19 patients and performed a quantitative polymerase chain reaction (qPCR) to assess viral load. Specimens positive with qPCR were subjected to virus isolation in Vero cells. We also used urine and stool samples to intranasally inoculate ferrets and evaluated the virus titres in nasal washes on 2, 4, 6 and 8 days post infection. Results SARS-CoV-2 RNA was detected in all naso/oropharyngeal swabs and saliva, urine and stool samples collected between days 8 and 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 log 10 copies/mL, saliva 1.07 ± 0.34–1.65 ± 0.46 log 10 copies/mL, stool 1.17 ± 0.32 log 10 copies/mL, naso/oropharyngeal swabs 1.18 ± 0.12–1.34 ± 0.30 log 10 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. Discussion Viable SARS-CoV-2 was demonstrated in saliva, urine and stool samples from COVID-19 patients up to days 11–15 of the clinical course. This result suggests that viable SARS-CoV-2 can be secreted in various clinical samples and respiratory specimens.

Strand-Specific Reverse Transcription PCR for Detection of Replicating SARS-CoV-2

“…We detected minus-strand RNA up to 30 days after symptom onset, which is longer than the 14-day period previously reported for subgenomic RNA ( 13 ), and 8–15 day period for viral culture ( 3 – 6 , 13 ). We detected minus-strand RNA in 2 patients beyond the typical period recommended for isolation.…”

Catching a resurgence: Increase in SARS-CoV-2 viral RNA identified in wastewater 48 h before COVID-19 clinical tests and 96 h before hospitalizations

“…Previous WBE work identified several possible normalization biomarkers in wastewater such as 5-Hydroxyindoleacetic acid ( Chen et al, 2014 ), caffeine and cotinine ( Rico et al, 2017 ). However, due to the higher incidence of SARS-CoV-2 viral particles in feces as compared to urine ( Collivignarelli et al, 2020 ; Jeong et al, 2020 ; Lodder and de Roda Husman, 2020 ; Zhurakivska et al, 2020 ), other biomarkers present in wastewater solids, such as pepper mild mottle virus (PMMoV) ( Jafferali et al, 2020 ; Kitajima et al, 2018 ; Rosario et al, 2009 ; Symonds et al, 2014 ) and crAssphage ( Crank et al, 2020 ; Polo et al, 2020 ) saw are being utilized for the normalization of SARS-CoV-2. Some recent studies have demonstrated that biomarker normalized SARS-CoV-2 viral signal may in fact track be capable of tracking the incidence of COVID-19 infections in the community ( Gerrity et al, 2021 ; Kitamura et al, 2021 ) more effectively than non-biomarker-normalized viral signal ( Jafferali et al, 2020 ; Wu et al, 2020 ), even if accounting for corrections due to flow or solids mass flux ( D'Aoust et al, 2021 ).…”

Critical role of neutralizing antibody for SARS-CoV-2 reinfection and transmission

“…In addition to respiratory droplet transmission, we have recently demonstrated the presence of infectious viruses in fecal specimens of infected ferrets and COVID-19 patients [ 19 , 27 ] which showed high RNA copy numbers (more than 1.0 log 10 copies/mL). The viral RNA copy numbers in heterologous SARS-CoV-2 infected groups 2 and 3 showed more than 1.0 log 10 copies/mL in rectal swabs at 2–4 dpi, suggesting the potential for infectious virus shedding through the gastrointestinal tract in ferrets with low NAb.…”