Keeping a two-metre distance from others may not be enough to stop the spread of coronavirus, a new study suggests. Health officials around the world have been urging members of the public to remain two metres apart from other people in order to prevent catching or spreading COVID-19. The study led by Dr Lydia Bourouiba, at the Massachusetts Institute of Technology suggests that that might not be a far enough distance to give protection from catching the highly contagious airborne disease.
Writing in the Journal of the American Medical Association (Jama), the authors said that current distance guidelines may be too short. "These distances are based on estimates of range that have not considered the possible presence of a high-momentum cloud carrying the droplets long distances.
"Given the turbulent puff cloud dynamic model, recommendations for separations of three feet to six feet (one metre to two metres) may underestimate the distance, timescale, and persistence over which the cloud and its pathogenic payload travel, thus generating an underappreciated potential exposure range for a healthcare worker.
"For these and other reasons, wearing of appropriate personal protection equipment is vitally important for health care workers caring for patients who may be infected, even if they are farther than six feet away from a patient."
The researchers said their findings were significant because public and healthcare workers may not realise they need to wear protective equipment even when not in the immediate vicinity of an infected patient. Chinese research claims to have found evidence that the virus can survive well in the conditions of a swimming pool. Eight people fell ill after an infected man visited a bathhouse in Huai’an, which is about 700km from Wuhan, the city believe to be at the centre of the outbreak.
Researchers from Nanjing Medical University say there was a cluster of eight cases of COVID-19 passed from a single “super-spreader” in a swimming bath. Previous reports have suggested that the virus doesn't do well in hot and humid conditions, but the researchers suggest this is likely wrong. According to a Daily Mail report, they say the case of the super-spreader in the swimming centre saw eight people who used or worked in the facility experience symptoms within days.
The Nanjing team published a research letter explaining their findings, and warning that, contrary to earlier studies, COVID-19 is unlikely to slowdown when temperatures rise.
The all-male patients in the study were aged between 24 and 50 with 89% of them reporting a fever and 78% reporting a cough. “Previous studies have demonstrated that the transmission rate of a virus is significantly weakened in an environment with high temperature and humidity,” the research team wrote.
“These results provide a potential epidemiological clue for this novel coronavirus.”
The team say their study is limited by a lack of detail about the transmission routes for all of the patients in the bath centre.
[link url="https://metro.co.uk/2020/03/29/two-metres-social-distance-not-enough-report-suggests-12474108/"]Full Metro UK report[/link]
[link url="https://www.dailymail.co.uk/sciencetech/article-8168025/Coronavirus-spread-warm-humid-conditions.html"]Full Daily Mail report[/link]
[link url="https://jamanetwork.com/journals/jama/fullarticle/2763852"]JAMA Insights study[/link]
[link url="https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2763473?utm_source=For_The_Media&utm_medium=referral&utm_campaign=ftm_links&utm_term=033020"]JAMA Network Open research letter[/link]