Tracking the Evolution of Clostridioides difficile and Implications for Healthcare

C difficile Infection

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The UK Health Security Agency is investigating a newly identified ribotype of Clostridioides difficile (CDI) that has emerged in England over the last 2 years. This ribotype named 955, shows similarities to the 027 ribotype, which caused international outbreaks of CDI with substantial morbidity and mortality in the 2000s. Findings from the study were presented as late-breaking research at the ESCMID Global Congress.

A total of 50 cases were identified, involving 48 unique individuals and 2 recurrences. 2 large hospital clusters occurred in one region, with sporadic instances identified across another 4 regions of England. The ribotype appears to transmit readily, causing severe disease or recurrence and significant mortality. Antibiotic susceptibility testing revealed resistance to metronidazole, a commonly used therapeutic agent for CDI.

The investigation involved convening a national incident management team and issuing briefing notes to the hospital and primary care sector to raise awareness of the issue. Whole genome sequencing and antimicrobial sensitivity testing were conducted to characterize the new ribotype.

The Cepheid PCR assay detects ribotype 955 as a 'presumptive 027' based on the detection of a deletion in the negative toxin regulator, aiding in identification. 2 outbreaks were difficult to control and required additional infection prevention and control measures, including patient decant followed by hydrogen peroxide vapor deep cleaning.

The findings underscore the need to raise awareness of this new ribotype and emphasize that metronidazole is not an appropriate therapeutic agent. Plans are underway to launch a whole genome sequencing-based national surveillance scheme for C diff in England to enhance monitoring efforts.

Findings from a recent study by the Centers for Disease Control and Prevention (CDC) discuss patient room shortages and the prevalence of other communicable diseases, the reassessment of patient isolation for CDI becomes imperative. This study was undertaken by researchers in a South Korean hospital where CDI patients were not isolated. The investigation aimed to ascertain the secondary CDI transmission rate.

Utilizing data from a real-time locating system and electronic medical records, the researchers analyzed patients who had direct and indirect contact with CDI index patients. Whole-genome sequencing was employed to identify secondary CDI transmission, serving as the primary outcome measure.

Among 909 direct and 2,711 indirect contact cases, only 2 instances of secondary transmission were observed, representing a minute proportion (2 (0.05%) of 3,620 cases). One transmission occurred through direct contact, while the other originated from environmental sources. Significantly, a mere 113 minutes of direct contact proved adequate for secondary CDI transmission.

"Our findings suggest that exhaustive standard preventive measures, including environmental decontamination, should take precedence over contact isolation for CDI patients in non-outbreak settings," Lead researcher, Hyukmin Lee MD PhD emphasizes, “Holds potential to mitigate the risk of secondary CDI transmission while optimizing resource utilization in healthcare facilities.”2

In conclusion, the emergence of the 955 ribotype of C diff in England, reminiscent of the 027 strain, demands urgent attention from the UK Health Security Agency. The investigation's findings and insights from a South Korean study advocate for a shift towards exhaustive preventive measures, such as environmental decontamination, over contact isolation. By prioritizing such strategies, healthcare facilities can mitigate CDI transmission risks and protect patient health.

References

1. Puleston R, Roulston K, Morgan K, et. al. Emergence of new concerning ribotype of Clostridioides difficile. Late breaking abstract #955 presented at ESCMID. April 27-30, 2024. Barcelona, Spain.
2. Lee H, Kim M, Kim J, Jeong S, et. al. Identifying Contact Time Required for Secondary Transmission of Clostridioides difficile Infections by Using Real-Time Locating System. Emerging Infectious Diseases. Published May 2024. Accessed April 29, 2024. https://wwwnc.cdc.gov/eid/article/30/5/23-1588_article