The Resilience of Clostridium difficile Spores Against Hospital Laundry Processes

What is Clostridium difficile (C. difficile) spores?

Clostridium difficile, commonly referred to as C. difficile, is a bacterium that can cause symptoms ranging from diarrhea to life-threatening inflammation of the colon. Infection is particularly problematic in hospital and long-term care settings, where the use of antibiotics can disrupt the normal gut flora, allowing C. difficile to thrive. The spores of C. difficile are especially concerning due to their hardy nature; they are resistant to many common cleaning agents and can survive for long periods on surfaces, including fabrics such as bed sheets.

The resilience of C. difficile spores poses a significant public health challenge. They can be easily transmitted from contaminated surfaces to patients, often via the hands of healthcare workers. This transmission can lead to outbreaks of C. difficile infections (CDIs), which are difficult to control and treat, and are associated with increased morbidity, mortality, and healthcare costs. The ability of C. difficile to form spores that can survive routine cleaning and disinfection processes is a key factor in its spread within healthcare environments.

In the continuous battle against healthcare-associated infections, the resilience of C. difficile spores presents a formidable challenge. A recent study aimed to quantify the survival of these spores through both simulated and commercial laundry processes used by the United Kingdom National Health System (UK NHS). The findings, which have significant implications for infection control protocols, are a cause for concern and call for immediate attention.

Objective:
The primary objective of the study was to determine the extent to which C. difficile spores can withstand the rigors of the UK NHS healthcare laundry process, as outlined in the Health Technical Memorandum (HTM) 01-04, both in vitro and on bed sheets from patients with confirmed C. difficile infections.

Methods:
The study employed a two-pronged approach. Firstly, it involved inoculating cotton sheets with C. difficile spores and subjecting them to a simulated washer extractor cycle that used an industrial bleach detergent containing 15% sodium hypochlorite and a peracetic acid sour with a pH between 2 and 4. Secondly, the research team assessed spore survival on hospital sheets that were naturally contaminated with C. difficile. These sheets were taken from the beds of patients diagnosed with C. difficile infection (CDI) and processed through a commercial laundry cycle, which included washing, drying, and finishing.

Results:
The simulated laundry process showed that two strains of C. difficile, NCTC 11209 and ribotype 001/072, could survive after washing cycle. What’s more concerning was the finding that naturally contaminated bedsheets retained a significant spore load even after the full commercial laundry process. Pre-laundering, the sheets had an average spore load of 51 CFU per 25 cm2, which only reduced to 33 CFU per 25 cm2 post-laundering, which corresponds to 35% reduction of bacterial loading. The C. difficile strain present was consistently identified as ribotype 001/072. Notably, both the simulated and actual laundering processes failed to meet the microbiological standards of eradicating pathogenic bacteria.

Conclusions:
The study's conclusions are alarming: C. difficile spores can survive the laundry processes designed to sanitize bedding in healthcare settings. This raises concerns about the potential for these spores to contribute to sporadic CDI outbreaks. The persistence of spores on bed sheets indicates a need for improved laundry protocols or alternative disinfection methods to ensure complete eradication of this pathogen.

Implications for Infection Control:
The implications of these findings are profound. If C. difficile spores can survive the wash cycle, there is a potential risk of cross-contamination, not only to patients but also to healthcare workers and the broader hospital environment. This study underscores the need for rigorous review and enhancement of current laundry practices within healthcare facilities.

What Does It Mean to Us:
Given the severity of CDIs and the robustness of C. difficile spores, the findings of the study are particularly concerning. They highlight an urgent need for healthcare facilities to reassess and potentially overhaul their laundry and disinfection protocols to ensure that they are capable of eliminating this tenacious pathogen. It also indicates the exposure risk laundry workers, caretakers and patients face, not only in hospitals but also senior living homes. Failure to do so not only puts patients at risk but also undermines the overall efforts to maintain a safe and infection-free healthcare environment.

Source: Infect. Control Hosp Epidemiol. 2018, 12, 1406-1411