Hospital DNA Experiment Shows How Quickly Germs Spread

harmless dna sample spread through half a hospital ward in 10 hours, experiment finds

By Jonny Lupsha, Wondrium Staff Writer

Scientists from a London college conducted an experiment showing germ spread, Science Alert reported. They put a harmless DNA sample on a hospital bed rail and it was quickly spread throughout the ward. No hospital can be totally germ-free.

Hospital bed
Medical staff pay keen attention to washing hands, cleaning and disinfecting surfaces, sterilizing medical equipment, and so on to prevent infection from starting or spreading. Photo by Hadrian / Shutterstock

According to Science Alert, a group of researchers in England has given a startling example of the risk of disease transmissibility on surfaces by tainting a single bed rail and watching germs spread. “Microbiologists from University College London (UCL) have now found that even in hospital rooms designed for containment of COVID-19 risks, viruses can easily be transferred to other areas,” the article said.

But how easily? “When viral DNA—one harmless to humans—was left on a hospital bed rail within a highly contained unit, it took fewer than 10 hours to spread to nearly half the ward, sticking around for at least five days at these sites. And that’s only when one bed rail was the source.”

In most cases, hospitals around the world are clean, with sterile environments throughout their buildings. However, it’s impossible for everywhere in a hospital to be completely devoid of germs.

Hospitals Are Great—Just Not Perfect

“Hospitals have the advantage of offering specialized care, as well as specialized technologies,” said Dr. Barry Fox, Clinical Professor of Infectious Disease at the University of Wisconsin School of Medicine and Public Health. “If you are ill and need hospitalization, it’s great to have a coordinated team of physicians, nurses, and other health care providers with experience in treating hospitalized patients.”

So why not go straight to the hospital for whatever ails you? Dr. Fox said that despite the excellent conditions and staff efforts of disinfection at a hospital, there is still a small risk of acquiring an illness while at the hospital, which you didn’t have when you went in. Hospital-acquired infections are even given a special name—nosocomial infections.

“Most nosocomial infections are bacterial, but some can be viral,” he said. “The major causes are pneumonia, surgical wound infections, and gastrointestinal or GI infections.”

Dr. Fox added that approximately 4% of hospital patients will acquire an infection from treatment.

Tracing Nosocomial Infections

Dr. Fox said that pneumonia and bloodstream infections acquired at hospitals are the most dangerous, so hospitals must learn how to stop them. However, given the sterilization conditions at hospitals, it’s hard to believe that nosocomial infections are a problem at all. So where do they come from?

“Of the pneumonia cases, nearly half are associated with being in intensive care and connected to a breathing machine known as a ventilator,” Dr. Fox said. “Since patients often have catheters placed in their bladders to monitor urine output, or catheters in their arms for intravenous fluids and medications, these anatomical sites are also prone to infection.”

The reason pneumonia and bloodstream infections are so dangerous, he said, is because they have the greatest chance of leading to severe consequences, including death.

Origins of nosocomial GI infections can often be traced to a bacterial disease called Clostridium difficile, which can be transmitted via poorly sanitized hands.

“Resistant bacteria play a more prominent role in nosocomial infections, as the germs have been kind of hanging out in the hospital environment, such as the bed rails, sinks, and in bathrooms,” Dr. Fox said. “Some examples include multiple drug resistant Gram-negative bacilli, and Methicillin-resistant Staph (MRSA).”

None of this means that you should ignore a physician’s advice to go to the hospital. The risks of contracting a nosocomial infection are quite low. However, they aren’t non-existent.

Image of Professor Barry Fox, M.D.

Dr. Barry Fox contributed to this article. Dr. Fox is a Clinical Professor of Infectious Disease at the University of Wisconsin School of Medicine and Public Health. He received his undergraduate degree in Molecular Biophysics and Biochemistry from Yale University and his medical degree from Vanderbilt University.