Coronavirus Study Implicates Fecal Transmission

Diarrhea may be a secondary dissemination route for the novel coronavirus, scientists said Friday after the publication of the latest study documenting patients with gastrointestinal pain and loose stool.

The primary path is believed to be virus-laden droplets from the cough of an infected person, although researchers said they focused heavily on patients with respiratory symptoms in early cases and may have overlooked those related to the digestive tract.

A total of 14 out of 138 patients (10 percent) in a Wuhan hospital reported by Chinese physicians in the Journal of the American Medical Association (JAMA) in the new paper initially had diarrhea and nausea one or two days before fever and labored breathing emerged.

The first US individual infected with 2019-nCoV also reported irregular bowel movements for two days and eventually the virus was found in his urine, and other such reports have been recorded in the Lancet in China, although infrequently.

“Importantly, 2019-nCoV has been reported elsewhere in the feces of patients with atypical abdominal symptoms, similar to SARS which was also shed in urine, suggesting a fecal transmission route which is highly transmissible,” William Keevil, a professor of environmental healthcare at the University of Southampton said in a comment to the UK’s Science Media Centre.

The possibility is not totally surprising to scientists, given that the new virus belongs to the same family as SARS.

Fecal transmission of SARS was implicated in sickening hundreds in Hong Kong’s Amoy Gardens housing estate in 2003. A rising plume of warm air originating in bathrooms contaminated several apartments and was transported by wind to adjacent buildings in the complex.

Based on the literature, “The 2019-nCoV virus found in the stool may be transmitted through the fecal spread,” added Jiayu Liao, a bioengineer at the University of California, Riverside.

But, he added, “We still do not know how long this virus can survive outside the body — HIV can only survive roughly 30 minutes outside the body — and what temperature range the 2019-nCoV is sensitive to.”

Fecal spread may present new challenges to the containment of the virus, but is more likely to be a problem inside hospitals that can become epidemic "amplifiers," said David Fisman, an University of Toronto epidemiologist.

Benjamin Neuman, a virology expert at Texas A&M University-Texarkana, cautioned that while fecal transmission was “certainly worth considering,” “droplets and touching contaminated surfaces then rubbing eyes, nose or mouth” were likely the main way the virus was transmitted based on current data.