Serial Screening for SARS-CoV-2 in Rectal Swabs of Symptomatic COVID-19 Patients

Abstract

We used serial rectal swabs to investigate the amount and duration of virus secretion through the gastrointestinal tract and assessed the association between fecal shedding and gastrointestinal symptoms and to clarify the clinical usefulness testing rectal swabs. We enrolled ten adult patients hospitalized with symptomatic coronavirus disease 2019 (COVID-19). Respiratory and stool specimens were collected by physicians. The presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was confirmed using real-time reverse-transcription polymerase chain reaction. All ten patients had respiratory symptoms, six had diarrhea, and seven were positive for SARS-CoV-2 on rectal swabs. The viral loads in the respiratory specimens was higher than those in the rectal specimens, and no rectal specimens were positive after the respiratory specimens became negative. There was no association between gastrointestinal symptoms, pneumonia, severity, and rectal viral load. Rectal swabs may play a role in detecting SARS-CoV-2 in individuals with suspected COVID-19, regardless of gastrointestinal symptoms.

Keywords: COVID-19; Coronavirus; Diarrhea; Polymerase Chain Reaction; SARS-CoV-2; Virus Shedding.

Fig. 1. The serial viral load from respiratory and stool specimens by threshold cycle values from real-time reverse-transcription polymerase chain reaction in all 10 cases.

Ct = cycle threshold.