A recent study conducted by researchers at the University of Plymouth in the UK has revealed that one of the primary chlorine disinfectants used in hospitals fails to eliminate the most common cause of antibiotic-associated illness in healthcare settings worldwide. The study focused on Clostridioides difficile, commonly known as C. diff, and found that the spores of this superbug remain unaffected even when treated with high concentrations of bleach commonly used in hospitals.
In fact, the researchers discovered that the chlorine chemicals were no more effective at damaging the C. diff spores than plain water with no additives when used as a surface disinfectant. This alarming finding suggests that individuals working and receiving treatment in clinical settings may unknowingly be exposed to the superbug.
With the overuse of disinfectants contributing to the rise of antimicrobial resistance (AMR) globally, the researchers emphasise the urgent need for alternative strategies to disinfect C. diff spores in order to break the chain of transmission in clinical environments.
Tina Joshi, Associate Professor at the University of Plymouth, who led the study alongside Humaira Ahmed, a fourth-year Medicine student, expressed concern over the increasing threat posed by superbugs due to the rise in antimicrobial resistance. Joshi highlighted that the study’s results not only fail to demonstrate the cleanliness and safety of clinical environments for staff and patients, but also underscore the ability of C. diff spores to withstand disinfection even at recommended concentrations of active chlorine.
C. diff is a microbe that causes diarrhea, colitis, and other bowel complications, affecting millions of people worldwide each year. The study specifically examined the response of C. diff spores from three different strains to three clinical concentrations of sodium hypochlorite. The spores were then placed on surgical scrubs and patient gowns, and scanning electron microscopes were used to identify any morphological changes to the outer spore coat.
Joshi emphasised the importance of understanding the interaction between these spores and disinfectants in order to effectively manage C. diff infections and reduce the burden of infection in healthcare settings. However, she also acknowledged that there are still unanswered questions regarding the extent of biocide tolerance within C. diff and whether it is affected by co-tolerance to antibiotics.