Author: John Anderer
Journal of Hospital Infection
Many Americans have avoided visiting emergency rooms and urgent care clinics during the COVID-19 pandemic in fear of catching the virus. Of course, this behavior poses a major health risk in and of itself, but an eye-opening new study lends credence to such a mindset. Researchers from University College London set out to see how quickly a virus could spread through a hospital setting. The stunning results demonstrate it doesn’t take very long at all for disease to infiltrate what is supposed to be a safe, sterile healthcare environment.
They purposely placed DNA from a plant virus (incapable of infecting humans) on a bedrail at Great Ormond Street Hospital. A tiny bit of water was even added to the viral plant DNA, in order to simulate SARS-CoV-2 cells found in respiratory samples. Just 10 hours later, that DNA was found in nearly half of all sampled areas in that ward. Moreover, the viral DNA persisted and lived on the hospital surfaces for at least five days.
That virus sample was placed on the hand rail of a hospital bed in a room intended for highly contagious, viral patients. Then, over the following five days, 44 different locations in the hospital were tested for the plant virus.
After 10 hours, the DNA had spread to 41% of tested areas, including other bed rails, door knobs, waiting room armrests, and even children’s toys and books. After three days, the virus was detected in 59% of tested locations, but by day five its presence had waned a bit, falling back down to 41%.
“Our study shows the important role that surfaces play in the transmission of a virus and how critical it is to adhere to good hand hygiene and cleaning,” comments senior study author Dr. Lena Ciric, from UCL Civil, Environmental & Geomatic Engineering, in a release. “Our surrogate was inoculated once to a single site, and was spread through the touching of surfaces by staff, patients and visitors. A person with SARS-CoV-2, though, will shed the virus on more than one site, through coughing, sneezing and touching surfaces.”
Most of the areas that tested positive for the plant virus were located fairly close to the original infection site (nearby beds, treatment rooms). In fact, by day three, a whopping 86% of sampled clinical areas tested positive. Meanwhile, by day four, 60% of tested locations within the immediate bed space area tested positive.
“People can become infected with Covid-19 through respiratory droplets produced during coughing or sneezing. Equally, if these droplets land on a surface, a person may become infected after coming into contact with the surface and then touching their eyes, nose or mouth,” explains co-author Dr. Elaine Cloutman-Green.
“Like SARS-CoV-2, the surrogate we used for the study could be removed with a disinfectant wipe or by washing hands with soap and water. Cleaning and handwashing represent our first line of defense against the virus and this study is a significant reminder that healthcare workers and all visitors to a clinical setting can help stop its spread through strict hand hygiene, cleaning of surfaces, and proper use of personal protective equipment (PPE),” she continues.
The study’s authors used viral DNA mixed with water for this study, but real SARS-CoV-2 is most often found in more sticky bodily fluids like mucus. This means SARS-CoV-2 can potentially spread even faster and more efficiently than the samples from this research.
Also, it’s worth noting that while this study did illustrate how quickly a virus left on a surface can spread through the surrounding environment, it didn’t measure how likely an individual is of actually contracting said virus.