The SARS-CoV-2 virus that causes COVID-19 may be capable of infecting human intestinal tract, in addition to the respiratory system, according to a study.
The study, published in the journal Nature Medicine, was conducted on human and bat organoids — miniaturised and simplified versions of the intestine produced in the laboratory.
In addition to reporting the creation of the first bat intestinal organoid, the study also included clinical isolation of the virus from a human stool sample, said the researchers from the University of Hong Kong.
Genetic analysis has revealed that SARS-CoV-2 is closely related to SARS-related coronaviruses found in horseshoe bats, they said.
However, the absence of laboratory models that can be used to study bat viruses limits study in this area, according to the researchers.
It is thought that bat organoids could potentially help in elucidating the origins of SARS-CoV-2, they said.
The researchers noted that the first bat organoid was derived from the horseshoe bat species Rhinolophus sinicus and simulates the cellular makeup of the intestinal epithelium.
They then assessed whether the organoids were susceptible to infection with SARS-CoV-2, and found that they were capable of sustaining viral replication.
The findings suggest that SARS-CoV-2 can infect bat intestinal cells, and thus, recapitulate the natural infection in bat intestine.
The researchers also investigated whether human intestinal organoids were susceptible to the virus and observed that viral replication took place here too.
They were also able to isolate SARS-CoV-2 from the stool specimen of a female patient diagnosed with COVID-19, which suggests that intestinal infection may have occurred.
The researchers note that the precise route by which human intestinal infection may take place is unclear, but that this could represent an additional route of viral transmission.