November 23, 2023: The widely used disinfectant, bleach, commonly employed in hospitals for cleaning medical equipment and surfaces is ineffective against the widespread superbug, Clostridium difficile (C. diff), raising questions about current disinfection practices in healthcare settings.
In a study conducted by the University of Plymouth, researchers have found that bleach is ineffective against the spores of the prevalent superbug C. diff.
The spores of C. diff, known for causing infections like diarrhea, colitis, and other bowel complications, remained entirely unaffected against potent concentrations of bleach. Even chlorine-based chemicals, commonly used in healthcare settings, demonstrated no more efficacy than plain water when utilized as a surface disinfectant. This discovery unveils a potential gap in current disinfection practices, urging a reevaluation of strategies in the ongoing battle against infectious agents.
Associate Professor Dr. Tina Joshi, specializing in molecular microbiology, conducted the study in collaboration with Humaira Ahmed, a fourth-year medical student from the Peninsula Medical School. The research focused on understanding how spores from three different strains of C. diff responded to practical concentrations of sodium hypochlorite, a common disinfectant.
The study, detailed in the journal Microbiology, involved introducing these spores onto surgical scrubs and patient gowns, closely analyzing them through scanning electron microscopes. The goal was to assess the effectiveness of disinfection methods on surfaces commonly found in medical settings.
Inefficacy of chlorine bleach
Dr. Joshi emphasized the potential impact of these findings on existing disinfection practices in the global medical community, suggesting that alternative solutions may need to be explored.
C. diff, a widespread infection affecting millions globally each year, has been linked to over twelve thousand deaths annually in the United States alone. Researchers argue that further investigation into alternative approaches for disinfecting C. diff spores is crucial to reducing the risk of patients and medical staff contracting and transmitting this superbug.
The study underscores the growing concern over the escalation of antimicrobial resistance, with Dr. Joshi warning, “With incidence of anti-microbial resistance on the rise, the threat posed by superbugs to human health is increasing.”
Contrary to assumptions about the efficacy of bleach in maintaining the cleanliness and safety of clinical environments, this study highlights the remarkable resilience of C. diff spores against disinfection, even at recommended active chlorine concentrations. Dr. Joshi concludes, “It shows we need disinfectants and guidelines that are fit for purpose and work in line with bacterial evolution, and the research should have a significant impact on current disinfection protocols in the medical field globally.”