TUESDAY, April 14, 2020 (HealthDay News) -- The presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA is detectable in the feces of COVID-19 patients and remains even after negative conversion in pharyngeal swabs, according to a study published online April 3 in the Journal of Medical Virology.
Yifei Chen, M.D., from Zhongnan Hospital of Wuhan University in China, and colleagues investigated SARS-CoV-2 shedding in the excreta of COVID-19 patients. Reverse-transcription polymerase chain reaction testing was used on pharyngeal swab specimens as well as stool and urine specimens from 42 laboratory-confirmed patients.
The researchers found that two-thirds of patients tested positive for SARS-CoV-2 RNA in stool specimens, which was not associated with the presence of gastrointestinal symptoms or the severity of illness. Just under two-thirds of patients (64.29 percent) remained positive for viral RNA in feces after pharyngeal swabs turned negative. After negative seroconversion of pharyngeal swabs, the duration of viral shedding from feces was seven days (range, six to 10), regardless of COVID-19 severity. There were no differences noted in the demographics, clinical characteristics, laboratory, and radiologic findings for patients who tested positive and negative for SARS-CoV-2 RNA in feces. In 10 patients, viral RNA was not detectable in urine specimens.
"In summary, our study results suggested the presence of SARS-CoV-2 RNA in feces of COVID-19 patients, and more importantly, viral shedding from feces might remain for a long time after negative conversion in pharyngeal swabs, suggesting that fecal-oral transmission may serve as an alternative infection route for SARS-CoV-2," the authors write.