Gastrointestinal SARS-CoV-2 Viral RNA Shedding and Viability

On March 11th, COVID-19 was declared a pandemic by the World Health Organization. The ensuing months saw an extensive allocation of resources toward combating the virus and the development of a vaccine. Despite extensive research on SARS-CoV-2, there remains little information regarding the implications of SARS-CoV-2 gastrointestinal shedding on COVID-19 disease. It is hypothesized that SARS-CoV-2 RNA is shed in the stool for up to several weeks and that viral protein persists in the GI tract. This study also explored calprotectin and zonulin levels, markers of inflammation, and intestinal permeability, respectively, to assess if increased viral shedding is associated with elevated levels of either. This study utilized RT-qPCR assays to confirm the presence of viral RNA. Subsequently, RT-qPCR positive samples were heat-inactivated and SARS-CoV-2 spike detection enzyme-linked immunosorbent assay (ELISA) was used to ascertain viral protein shedding. Additional ELISA was performed to assess zonulin and calprotectin levels. Results indicated that 30 of the 758 unique samples were confirmed SARS-CoV-2 positive by RT-qPCR. Spike protein was ultimately not detected by ELISA. Additionally, no significant increase in zonulin was observed in patient samples when comparing RT-qPCR positive and negative Samples. A notable upwards trend approaching significance in calprotectin levels existed for patients who tested positive for SARS-CoV-2 by RT-qPCR, though, it was found that no correlation existed between SARS-CoV-2 copy number and calprotectin levels. Understanding the interaction between SARS-CoV-2 and the GI tract may therefore have significant clinical implications and this study demonstrates the need for additional studies to garner a more comprehensive understanding.