Turns out even after a load of laundry, dangerous bacteria still lingers on hospital sheets. It has been found on beds and the masks and scrubs worn by healthcare workers. These bacteria can spread amongst patients and staff, sometimes causing deadly infections. Recently a light-activated product was tested by Canadian researchers who believe it could be a game changer in the battle against bacteria. So what is the brilliant idea behind this germ-killing coating?
Not everyone entering a hospital is sick, but a growing number become ill after being admitted. Deadly bacteria like Escherichia coli (E. coli) and Methicillin-resistant Staphylococcus aureus (MRSA) have been linked to hospital acquired infections in hundreds of patients. One recent German study estimated that around 1.5% of all patients get an infection at the hospital tied to a multidrug-resistant organism. About a quarter of them die –– or about 1,500 every year in Germany alone. The World Health Organization estimates that the number of similar deaths in the U.S. approaches 100,000.
Despite enormous expenditures of time and money the problem persists. In one test, researchers soaked bed sheets in Clostridium difficile –– which can cause deadly infections in already immune-compromised or otherwise susceptible patients. Yet despite washing the sheets in a commercial washing machine using industrial detergent and temperatures considered high enough to disinfect, the bacteria still lingered. Even worse, during the wash cycle, contaminated sheets transmitted the bacteria to clean sheets.
These types of tests demonstrate how important it is to find a way to eliminate bacterial spread. After all, the risk of getting a hospital-acquired infection may be lower than the risk of leaving a condition or disease untreated. That doesn’t mean patients (or staff) want to gamble with their health.
While the focus on surface contamination has diminished since the early days of the COVID-19 pandemic, that doesn’t mean disinfecting doesn’t matter. Doctors, nurses, and other healthcare workers can harbor the virus on their clothing and masks. In fact, studies suggest it can survive for a week on a contaminated face mask. Finding an inexpensive way to kill it is valuable. Recently researchers at the University of British Columbia discovered a coating that can kill germs from E. coli bacteria to the novel coronavirus.
At UBC, researchers tested a bacteria-killing polymer that relies on a sterilizing form of oxygen. After soaking fabric in this solution, they exposed it to ultraviolet light. The solution solidified. Dr. Michael Wolf, a professor of chemistry at UBC and the senior author of the study explains: “This coating has both passive and active antimicrobial properties, killing microbes immediately upon contact, which is then amped up when sunlight hits the cloth.”
Because sunlight isn’t always available, researchers also tested it under a green light bulb. With the fabric protected by the coating, they then soaked it in a brew of E. coli and MRSA. After letting the fabric sit for half an hour, they tested the cloth. Some 85 percent of viable E. coli bacteria still remained as did 95 percent of viable MRSA bacteria. The researchers then turned on a green light bulb. Thirty minutes later, just three per cent of the E. coli bacteria and 35 percent of the viable MRSA bacteria remained.
The coating has been safely tested on people and can be used on everything from cotton and silk to denim or polyester. Although more testing will be needed, it may eventually be available to consumers who have already popularized odor-reducing fabrics where a bacteria killing coating has been deployed. Researchers have applied for a patent in the U.S. and say activewear companies along with manufacturers of hospital clothing have been in touch.
Written by John Bankston
- Mortality attributable to hospital acquired infections with multidrug-resistant bacteria in a large group of German hospitals
- Health care-associated infections
- From ward to washer: The survival of Clostridium difficile spores on hospital bed sheets through a commercial UK NHS healthcare laundry process
- Photodynamic and Contact Killing Polymeric Fabric Coating for Bacteria and SARS-CoV-2