Further studies of air samples in hospital wards treating COVID-19 patients uncovered that the virus could travel up to 13 feet, more than twice the distance current physical distancing guidelines mandate. The investigation was conducted by Chinese researchers led by a team at the Academy of Military Medical Sciences in Beijing, who published their findings in Emerging Infectious Diseases, a journal of the U.S. Centers for Disease Control and Prevention.
The researchers who discovered traces of the disease at 13 feet of distance specified that the particles found were not inevitably infectious. Samples were gathered from a COVID-19 ward at Huoshenshan Hospital in Wuhan, which housed a total of 24 patients between Feb. 19 and March 2.
They found that the virus was most heavily concentrated on the floors of the wards and said a potential cause could be due to gravity bringing the virus droplets to the ground. “Half of the samples from the soles of the ICU medical staff shoes tested positive,” the team wrote. “Therefore, the soles of medical staff shoes might function as carriers.”
The research group also studied aerosol transmissions, or virus droplets that become suspended in the air for several hours. They found that aerosols containing particles of the virus were primarily concentrated closer to the downstream from patients at up to 13 feet while some smaller quantities were found upstream, up to eight feet.
The study of coronavirus particles remaining in aerosols is controversial; a previous study from Massachusetts Institute of Technology (MIT) claiming the virus could travel anywhere from 23 to 27 feet was rebuked by Anthony Fauci, the nation’s leading infectious disease expert. He called the MIT research “misleading,” noting that it would take a “very, very robust, vigorous, achoo sneeze” for droplets to travel that far, adding that the research was “not practical.”
The World Health Organization has also noted the risk for aerosolized transmission is not an outstanding threat for most people, according to the report. U.S. health officials have told people to wear masks or cover their faces when out in public to minimize the chances of transmitting the virus through talking or breathing close to other individuals.