Diarrhea, a secondary route of transmission for coronavirus
Diarrhea may be a secondary route of transmission for the new coronavirus, scientists reported Friday after the publication of a study that accounted for patients with abdominal symptoms and loose stools.
While the main route is thought to be the virus-laden droplets from a cough of an infected person, researchers said they focused largely on patients with respiratory symptoms and may have overlooked others, related to the digestive system.
A total of 14 of 138 cases (10%) from a Wuhan hospital, analyzed by Chinese scientists in the Journal of the American Medical Association (JAMA), initially had diarrhea and nausea one or two days before developing fever and breathing difficulties.
The first patient in the United States diagnosed with 2019-nCoV also experienced loose stools for two days, and the virus was subsequently detected in his stool. This is in addition to other similar cases in China documented in the British medical journal The Lancet, although recorded with low frequency.
"It is important to note that 2019-nCoV has been reported in other parts of the feces of patients with atypical abdominal symptoms, similar to SARS which was also discharged in the urine, suggesting a route of fecal transmission that is highly transmissible," William Keevil, professor of environmental health at the University of Southampton, said in a commentary to the UK's Science Media Center.
That possibility is not entirely surprising to the scientific community, given that the new virus belongs to the SARS family.
Fecal transmission of SARS infected hundreds of people in Hong Kong's Amoy Gardens estate in 2003. A plume of hot air that originated in the bathrooms contaminated several apartments and was carried by the wind to adjacent buildings in the complex.
According to the literature, "the 2019-nCoV virus found in feces can be transmitted through the fecal spread," added Jiayu Liao, a bioengineer at the University of California, Riverside.
But, he added, "We still don't know how long this virus can survive outside the body (HIV can only survive about 30 minutes outside the body) and what temperature range 2019-nCoV is sensitive to.
Spreading through fecal matter introduces new challenges about the virus, but that's more likely to be a problem within hospitals, said David Fisman, an epidemiologist at the University of Toronto.
Benjamin Neuman, a virus expert at Texas A&M University-Texarkana, cautioned that while the fecal transmission was not negligible, "droplets and contact with infected surfaces and then touching the eyes, nose or mouth" were most likely the main routes of virus transmission, according to available data.