A study from University of Washington researchers uncovers how hospital laundry facilities may harbor dangerous Clostridium difficile spores, creating a potential community source for the bacterial pathogen.
In 2015, there were approximately 500,000 infections caused by Clostridium difficile bacteria in the United States, leading to 15,000 deaths and making the pathogen one of the Centers for Disease Control and Prevention’s (CDC) “biggest threats.” The bacteria cause a potentially deadly form of diarrhea that is most dangerous in older adults: the CDC reports that 80% of C. difficile-related deaths occur in patients 65 years and older.
One of the most prevalent healthcare-associated infections, C. difficile infections are notorious for plaguing today’s hospital patients. Recently, however, researchers discovered one way that C. difficile leaves hospitals and contaminates outside environments: while individuals are on an antibiotic regimen, and during the month after their course of treatment, they are 7 to 10 times more likely to get C. difficile infections.
A team of researchers from the University of Washington in Seattle studied how C. difficile is transmitted as both a hospital-associated and community-acquired pathogen. In their study published in the journal FEMS Microbiology Letters, the authors note that although C. difficile infections are highly associated with healthcare settings, about one-quarter of these infections occur due to exposure to the bacteria in the community and environment. Water, soil, livestock, meats, vegetables, and pets are some of the common carriers of C. difficile within the community, but in this study, the researchers looked at hospital linens as a potential way that C. difficile spores are spread into the environment.
People with C. difficile infections shed bacterial spores in their feces, and these spores are notoriously hardy, defying both antibiotic medications in the body and disinfectant cleaners outside the body. The spores often persist on hospital room and bathroom surfaces and on rectal thermometers and other medical devices that infected patients may come in contact with. Healthcare workers who pick up C. difficile spores on their clothes from patients or surfaces can then pass them on to other patients. Researchers have used irradiation from UV light devices to disinfect hospital room surfaces to some success, and other trials to swap high-touch items with antimicrobial copper replacements have also proven effective in eliminating C. difficile spores.
With samples collected from the University of Washington Consolidated Laundry facility—which processes around 300,000 pounds of laundry each week from six Seattle-area hospitals, 30 outpatient clinics, and the Washington National Primate Research Center—the researchers looked to determine if they could culture C. difficile from the facility’s surfaces. During the course of 2015, the team collected 240 surface samples in January, April, July, and October. Of those samples, 120 were from “dirty areas,” such as the receiving area and the primary and secondary sorting areas, and 120 were taken from “clean areas,” such as the folding and processing areas.
Of the samples collected in the dirty areas, 25 came up positive for C. difficile compared with only two of the samples collected in the clean areas (which were from January and October). The researchers noted that most contaminated samples were collected in April, and C. difficile infections may be seasonal and correlate with antibiotic use.
“As expected, the dirty area was much more likely to be contaminated than the clean areas due to the handling of soiled linens,” write the authors. “We did not determine personnel contamination, if employees had diarrhea during the study period, or collect fecal samples for culture. However, in a pilot project, we found C. difficile on the outside cabin door of a facility truck that transports both clean and dirty linens to and from the laundry. This suggests that a potential reservoir of C. difficile could include trucks that carry laundry and should be studied in the future of soiled linens."
“This is the first study to examine C. difficile environmental contamination in an industrial laundry facility,” the authors conclude. “The study suggests that soiled clinical linens are a potential source of C. difficile surface contamination and more studies need to be done to determine if this type of contamination is a risk to laundry workers.”