Clostridioides difficile infection: Evidence-based approaches for healthcare professionals

---

Reference: September 2025 | Issue 9 | Vol 11 | Page 54

---

Clostridioides difficile (formerly Clostridium difficile) infection (CDI), or C. difficile as it is commonly known, can have profound and enduring consequences for patients’ health-related quality of life – exerting an influence on their physical, psychological, social, and occupational capabilities for a prolonged period.¹

C. difficile is a highly contagious bacterium, commonly found in soil and animal intestinal tracts, which constitutes normal gastrointestinal flora in around 3 per cent of healthy adults, and is also found in up to 20 per cent of adults undergoing antimicrobial therapy. Transmission occurs via the faecal-oral route following contact with an infected person or spores in the environment, with symptoms ranging from mild gastrointestinal disturbances and self-resolving diarrhoea to life-threatening colitis.^2,3

C. difficile is the primary cause of healthcare-associated diarrhoeal infection, and its reclassification as a ‘superbug’ has been proposed as it has become a significant worry for the healthcare sector owing to its global prevalence, limited treatment choices, evolution of hypervirulent ribotypes, and significant rates of resurgence and case fatality.^3,4,5 Added to these concerns, CDI induces lengthy hospital stays, treatment expenses, and indirect societal costs, all of which have significant economic ramifications for both the healthcare system and patient.⁶

Over the past several years, advances in epidemiology, diagnostics, and management have emerged, alongside continuing concerns regarding the resilience of C. difficile within healthcare environments.

This article provides an up-to-date, evidence-based review of CDI, focusing on risk factors, testing and diagnosis, classification, management, and infection prevention strategies, with reference to recent literature to further inform best practice.

Epidemiology

C. difficile is an anaerobic, spore-forming, Gram-positive bacterium, commonly associated with gastrointestinal disturbances ranging from mild diarrhoea to life-threatening pseudomembranous colitis. Its pathogenicity is mediated by two main toxins – toxin A and toxin B – both of which disrupt the integrity of colonic epithelial cells and provoke inflammation.² The case definition for CDI requires the presence of three or more loose/watery bowel movements – unexplained or different for the patient in a 24-hour period – and laboratory evidence of toxigenic C. difficile or its toxin(s) or, in severe cases, colonoscopic or histopathological findings of pseudomembranous colitis.^7,8

CDI remains a public health challenge due to its recurrence, severity, and evolving epidemiology.^9,10 Despite a substantial decline in diarrhoeal-related global mortality over the last 20 years, CDI hospital cases continue to exhibit high mortality; 30-day mortality rate for hospital cases was 18.6 per cent versus 8.6 per cent in controls, with ribotype 181 being the most prevalent.^11,12 However, outbreaks of hypervirulent strains, such as ribotypes 027/NAP1/B1, continue to cause periodic surges, with increased morbidity, mortality, and recurrence risk.¹³ Recurrence rates hover at 10 to 25 per cent after a first episode, rising further with each recurrence.^14,15

While historically considered a hospital-acquired infection, recent data has witnessed a shifting epidemiology, displaying a rising proportion of community-acquired CDI cases – now accounting for around one-third of all diagnoses in the US and Europe. Community-acquired CDI often affects younger and healthier populations, highlighting the need for a greater awareness and understanding for those working in community settings.^9,16

Surveillance across Europe continues to demonstrate substantial variation in incidence, partly due to differences in case definitions and laboratory diagnostics.¹⁷ However, the most recent point prevalence survey (2022-2023) from the European Centre for Disease Prevention and Control (ECDC) reported that the average incidence of CDI in European acute care hospitals was 5.2 cases per 10,000 patient-days, showing a slight increase compared to previous years.¹⁸

Risk factors

CDI risk arises from a complex interplay of host, microbial, and environmental factors. Recent meta-analyses and cohort studies confirm the multifactorial nature of susceptibility.^19,20

Key risk factors for CDI include:

• Antibiotic exposure: CDIs are inextricably linked to antimicrobial agent-induced disruption of the intestinal microbiota and remains the single most important risk factor across all age groups.³ Clindamycin, fluoroquinolones, broad-spectrum beta-lactams, cephalosporins, and carbapenems are especially implicated.^13,21
• Healthcare exposure: Prolonged or repeated hospital and long-term care stays dramatically increase exposure to both spores and antibiotics.^10,16 Contaminated surfaces, equipment, or healthcare workers’ (HCWs) hands can expose patients to resilient C. difficile spores.^22,23
• Advanced age (≥65 years): Older adults are at increased risk for both primary and recurrent disease due to immunosenescence and comorbidities.^12,19
• Immunosuppression: Patients with malignancy, organ transplants, or immunosuppressive medication usage are significantly more vulnerable to severe and recurrent forms of CDI.^14,19
• Comorbidities: Chronic kidney disease, inflammatory bowel disease, diabetes, and other serious illnesses increase CDI risk and worsen outcomes.^1,8,19 Underlying gastrointestinal disorders or surgeries can also increase risk.³
• Gastric acid suppression: Proton pump inhibitor (PPI) use, or other acid-suppressing medications have been consistently associated with increased risk, possibly by allowing spores to survive gastric passage.^1,16,24
• Enteral feeding: Feeding tubes can increase risk through both microbial and mechanical means.^1,24
• History of CDI: Recurrence is common; especially within two months of the initial infection, particularly with subsequent antibiotic exposure.^4,14
• Community exposure: Recent studies highlight a growing burden of community-acquired CDI, with risk factors including contact with asymptomatic carriers, outpatient healthcare contact, and household transmission.^6,16

Diagnosis

Accurate and prompt diagnosis of CDI is critical for both effective patient management and infection prevention and control.⁹ Recent guidelines and consensus statements emphasise the need for a two-pronged diagnostic strategy: Clinical suspicion plus laboratory evidence.^7,8,10,25

Clinical suspicion

• Unexplained, new onset of more than three unformed stools in 24 hours in an at-risk individual.

Laboratory testing

• Initial two-step stool screening for glutamate dehydrogenase (GDH) antigen and toxin A and B enzyme immunoassays (EIA).
• GDH antigen testing – highly sensitive for C. difficile antigen. It is used as a screening test for presence of the organism but not specific for toxigenic strains.⁸
• Stool toxin testing (EIA) – detects toxins A and B. It is rapid and specific but less sensitive than molecular methods. EIA is useful for confirming active disease in symptomatic patients.⁸
• Confirmation with nucleic acid amplification testing (NAAT) for toxigenic C. difficile genes if discrepancies exist. NAAT is a polymerase chain reaction (PCR)-based assay that detects toxin genes and is highly sensitive and specific. However, it may detect asymptomatic colonisation – clinical correlation of symptoms is essential to prevent unnecessary treatment of colonisation.^7,16

Interpretation of test results

• Toxin positive: Confirms active toxin-mediated disease in symptomatic patients and warrants prompt treatment.
• GDH+/Toxin-/NAAT+: Indicates the presence of a toxigenic strain but not necessarily infection. Important to correlate with clinical symptoms before starting treatment.
• NAAT+ without symptoms: Suggests colonisation. Do not treat unless clinical symptoms are present.⁸
• Repeat testing within the same episode is discouraged, as modern assays have high negative predictive value and excessive repeat testing can lead to overtreatment.^7,10
• Diagnosis of severe cases: Clinical severity and complications can be assessed through laboratory markers (elevated white cell count, rising creatinine, hypoalbuminaemia) and imaging if indicated.⁹
• Abdominal x-ray or CT may be indicated for suspected toxic megacolon or severe colitis, especially if ileus is present.¹⁴

Researchers are currently evaluating faecal calprotectin, lactoferrin, and other inflammatory markers to help differentiate between colonisation and true infection.¹⁶

CDI can be classified based on severity, onset, and case type.^10,26,27

Severity

• Mild-moderate: Diarrhoea with no signs of severe disease.
• Severe: Significant leukocytosis, acute renal failure, hypotension, or evidence of colitis.
• Fulminant/complicated: Hypotension, shock, ileus, or megacolon.

Onset

• Healthcare-associated: Onset ≥48 hours after hospital admission or within four weeks of discharge.
• Community-acquired: Onset outside hospital or within 48 hours of admission, and no recent admission in past 12 weeks.

Case type

• New case: The first episode of CDI or a subsequent episode of CDI with onset of symptoms more than eight weeks after the onset of a previous episode.
• Recurrent case: A patient with an episode of CDI that occurs within eight weeks following the onset of a previous episode provided that CDI symptoms from the earlier episode resolved with or without therapy.

Management

The immediate discontinuation of both unnecessary antimicrobials and acid-suppressing agents, when feasible, is an important initial treatment step.^9,25 Anti-motility medications should also be avoided. In deciding antimicrobial therapy, current guidelines emphasise the importance of considering recurrence risk as a key factor in determining the appropriate treatment strategy for each patient, rather than focusing solely on disease severity.²⁸ Individuals with a high recurrence risk include those greater than 65 years, plus the addition of one or more of the following:²⁵

• Previous CDI episode
• Hospitalisation in the past three months
• Healthcare-associated CDI
• Use of additional antibiotics
• Commencement of PPIs during or after CDI diagnosis.

For patients with mild symptoms (<3 episodes of diarrhoea in 24 hours), the inciting antibiotic should be discontinued, if possible, and the patient should be monitored for 48 hours before initiating CDI-specific treatment.²⁵

For moderate-severe symptoms (≥3 episodes of diarrhoea in 24 hours), recommended first-line treatment is oral vancomycin (standard or pulsed/tapered regimen) for non-severe and severe CDI.^25,28 An alternative is the narrow spectrum macrocyclic antibiotic, fidaxomicin, which has shown superiority over traditional antimicrobials as it demonstrates reduced recurrence rates compared to vancomycin and better preservation of gut microbiota. It is increasingly recommended as a first-line agent for high-risk individuals.^4,6

The addition of intravenous metronidazole along with oral vancomycin or fidaxomicin may also be considered for patients with severe or severe-complicated disease.²⁸ Oral metronidazole is no longer recommended as an efficacious treatment. Additionally, reports of increasing metronidazole resistant ribotypes are emerging in recent years.^29,30 It should be used only for non-severe cases if vancomycin/fidaxomicin are unavailable.⁹

Treatments for recurrent CDI include fidaxomicin or tapered/pulsed vancomycin.²⁸

Faecal microbiota transplant is recommended after multiple recurrences, despite its higher cost ,as it has demonstrated greater efficacy in preventing recurrence with a proven cost-benefit value and may also be beneficial in severe disease.^4,6,31

Treatment options for CDI, although limited, are evolving beyond the traditional management with metronidazole and vancomycin, reflecting recent advances in antimicrobial stewardship (AMS) and emerging therapies. Novel treatments such as live biotherapeutic products, monoclonal antibodies, antibiotic inhibitors, vaccines, and bacteriophages are currently being trialled and developed and may soon supplement current regimens.³²

In addition to appropriate antimicrobial therapy, supportive management includes fluid and electrolyte replacement, patient education, provision of nutritional support as clinically indicated, and vigilant monitoring for potential complications. The diligent maintenance of stool and fluid balance charts are fundamental for monitoring treatment efficacy and informing subsequent clinical management decisions.

Management of patients with severe CDI should involve a multidisciplinary team approach, including a clinical microbiologist and/or infectious diseases specialist, gastroenterologist, surgeon, and pharmacist as appropriate, and therefore, patients with severe CDI in the community should be referred to hospital.²⁵

Severe and life-threatening CDI is generally acknowledged as a medical emergency, with consensus that such cases warrant urgent clinical attention and appropriate management.³¹ Early consideration of surgical intervention is recommended for severe cases of CDI that present with possible complications such as toxic megacolon or intestinal perforation.³¹

Prevention strategies

C. difficile can be found in both spore-forming and vegetative states, with resilient spores exhibiting the capacity to persist for several months on portable equipment and environmental surfaces.^22,23 Due to their resilience, C. difficile spores have become endemic within hospital environments and are, therefore, easily carried on equipment and the hands of both patients and HCWs.²⁴

Consequently, preventing both C. difficile transmission and infection necessitates the proactive and collective application of multiple evidenced-based strategies which include active surveillance for cases and outbreaks, early detection, effective hand hygiene, ensuring thorough sporicidal-based environmental and equipment cleaning, the implementation of patient isolation and contact precautions, and the promotion of AMS.^9,10,33,34

AMS remains an essential pillar in both the prevention and optimal management of CDI. Recognised as a critical intervention by the World Health Organisation (WHO) and major national guidelines, AMS underpins evidence-based strategies for improving patient outcomes through:^8,16,35

• Evaluation of antibiotic prescribing: Clinicians should systematically assess the indication, spectrum, and duration for all antibiotic regimens.⁸
• Prioritisation of narrow-spectrum agents: The selection of the most targeted, appropriate agent and timely discontinuation are recommended to minimise risk.⁷
• Continuous audit and feedback: Regular monitoring of CDI incidence and antibiotic utilisation patterns is necessary, with structured feedback and educational initiatives provided to prescribers.¹⁶
• Commitment to education and culture change: Sustained professional learning is fundamental for the long-term success of AMS interventions.³⁶
• Guideline adherence and monitoring: Compliance with both local and international clinical practice guidelines should be routinely evaluated and promoted.⁸
• Emerging evidence highlights that even short-term administration of broad-spectrum antibiotics may significantly elevate CDI risk, further reinforcing the need for robust AMS at every point of care.²⁰

Most isolation and contact precautions apply to the hospitalised patient, but several are universally applicable and vital regardless of the clinical setting. In addition to standard precautions, one of the front-line management strategies implemented by HCWs in the care of suspected or confirmed CDI patients is patient isolation and the application of contact-based precautions to help contain and prevent onward transmission of C. difficile, and thereby lower the incidence of healthcare-associated infections (HCAIs).³⁷

The addition of each element involved in contact-precautions is designed to collectively minimise transmission risk, including patient isolation with a dedicated toilet and equipment, wearing gowns and gloves when entering a patient’s room, appropriate hand hygiene including the use of soap and water when indicated, and enhanced sporicidal disinfection.^9,23 Clear signage must indicate contact precautions, and all ancillary staff and visitors should receive guidance on appropriate infection prevention and control measures.^7,21

Dedicated, disposable equipment is preferred and shared items must be thoroughly cleaned and disinfected with a sporicidal agent between uses.³⁸ Ensuring that the manufacturer’s recommended contact time for disinfectants is observed is essential before re-using equipment with another patient. Additionally, the adoption of CDI care bundles has been found to be beneficial in reducing CDI rates.³⁹

It is important that staff and visitors are aware that the use of soap and water is recommended for hand hygiene after contact with CDI patients or their environment, as alcohol-based hand rubs are ineffective against spores which need to be physically washed off the hands.⁸ Of concern, a recent study examining nurses’ knowledge on CDI highlighted that only 28.5 per cent of nurses were aware of this fact.⁴⁰

However, guidance has stated that although hand washing with soap and water is required to effectively remove spores, alcohol-based hand rubs may be used in situations where gloves are used and hands are evidently clean and not likely to be contaminated with faeces or be in contact with an area where faecal contamination is possible.^7,25

Performing hand hygiene based on the WHO ‘Five Moments for Hand Hygiene’ is universally recognised as one of the most important strategies to help prevent transmission of infection.^7,16,41 It recommends hand hygiene should be performed:

• Before patient contact
• Before an aseptic task
• After body fluid exposure risk
• After patient contact
• After contact with patient surroundings.

Isolation precautions have several documented benefits and risks and, where possible, the isolation of patients, until at least 48 hours after resolution of symptoms, is widely recommended in most international and Irish CDI guidance documents.^2,25,27,42 However, there is ongoing debate regarding the adequacy of this timeframe, and whether it is also necessary to isolate colonised patients in order to further mitigate C. difficile transmission.^37,43

The Infectious Diseases Society of America advises that isolation can be prolonged up to when a patient is discharged in higher incidence situations.⁹ This guidance is based on observational research which revealed that HCWs’ hands could continue to become contaminated for up to six weeks after a patient’s symptoms had resolved and contact precautions were ceased, which may warrant further research and a possible universal review of isolation guidance.⁴⁴

It has been demonstrated that increased CDI pressure (a higher incidence or prevalence within a specific healthcare facility), including having an overlapped stay with a CDI case, particularly staying in the same or adjacent rooms, significantly increases the likelihood of acquiring CDI.^45,46 A recent study found that after admission to a healthcare facility, almost one in 10 individuals acquired new C. difficile colonisation from their stay.⁴⁷

Other studies reveal a high rate of conversion from admitted carriers, whereby almost 30 per cent of carriers had proceeded to infection, and had a 24-times increased risk compared to non-carriers – convincing statistics that could form the basis of a favourable case for isolating this cohort of patients.^43,48

C. difficile-colonised individuals are recognised to play a contributing role in the hospital-wide incidence of CDI, with studies showing no discernible difference in the stool toxin levels between individuals with CDI and those of asymptomatic carriers.^49,50 Additionally, C. difficile carriers’ rooms have been found to have an equal contamination burden as those patients with current infection.⁵¹

Evaluating new preventative interventions is crucial to help curb transmission of C. difficile.⁵¹ A number of studies have documented an incremental and substantial decline in CDI rates following the implementation of detection and isolation practices for asymptomatic carriers, with an estimated overall reduction in projected CDI-HCAI cases ranging from 62 per cent to an impressive 84 per cent.^52-54

Conceptually, CDI could be reduced through screening and the prompt implementation of carrier isolation, which would help to facilitate early antibiotic stewardship input aimed at potentially averting development to clinical illness.⁵¹ Further evidence-based research is required – however, based on the available data, it is possible to argue that a comprehensive evaluation of patient isolation practices and guidelines in the management of both CDI patients and carriers is needed to determine whether modifications are necessary.

Effective environmental cleaning

Attempting to avert the initial transmission of pathogens to patients is crucial, as treatment for infections is not always successful.⁵⁵ C. difficile poses a particular risk to patients as spores are extremely resilient and unaffected by routine cleaning and many disinfectants, which presents a challenging obstacle for infection preventionists.^9,56 When pathogen reduction is necessary, a cleaning step must always precede disinfection. Alternatively, a dual-action product (cleans and disinfects) may be used where suitable.⁵⁷

In the management of C. difficile, a sporicidal-specific agent should be used, ensuring the prescribed manufacturer contact-time, to thoroughly disinfect surfaces or objects during daily cleaning, as well as when performing an entire terminal clean upon patient discharge.²³ Surprisingly, a recent study revealed that one-third of nurses were unaware of the requirement for using sporicidal agents.⁴⁰ During terminal cleaning, laboratory-based studies have shown that C. difficile can be predominantly eradicated from the environment with the proficient use of sporicidal disinfectants.⁵⁸ However, the level of C. difficile environmental contamination has repeatedly been shown to be high throughout the literature.^56,59,60

A comprehensive multi-country meta-analysis documented the pooled prevalence of C. difficile in various devices, rooms, and hospital wards.⁶¹ Pooled results exhibited chair arms (43.8%), call buttons (44.1%), beds (35%), keyboards (15%), laundry areas (14.3%), and floor corners (63.2%) as having the greatest prevalence of contaminated areas. Of interest, in this study countries with a high incidence of C. difficile in hospital surroundings also tended to have an elevated incidence of CDI-HCAIs. However, the authors emphasise that additional risk factors, such as antibiotic consumption, may play a supporting role and was not examined in this study.

Research has revealed a greater variety of bacteria on textiles compared to hard surfaces, which has been surmised as being correlated with the difference in cleaning frequency between both.⁶² Hospital privacy curtains are a high-contact area, which are known to acquire bacterial contamination within a comparatively brief timeframe, and may also present a significant transmission risk due to their periodic cleaning schedule and the likelihood that HCWs will neglect to clean their hands after contact with them.^63,64

The acquisition of CDI can be significantly influenced by the presence of a previous room occupant who had CDI, according to research.^23,65,66 A mathematical investigation demonstrated that, on average, more than 75 per cent of colonised patients acquire colonisation via high-touch objects, including bedframes and tables, drip stands, door handles, sinks and toilets, even with extra cleaning.⁶⁷ Consequently, contact with these contaminated areas may perhaps be the starting point of the chain of events that lead to the development of infection in future cases.

Despite the overall indisputable significance of effective cleaning in preventing the spread of infection, problems persist.⁵⁵ Unclear evidence and the lack of uniform guidelines among experts has sparked concerns on whether cleaning and disinfecting once daily is sufficient to lower the potential for transmission, particularly on surfaces that are frequently touched.^55,57

Current Irish guidance advises that CDI patients’ rooms are cleaned and disinfected ‘at least daily’ and recommends using a chlorine-based sporicidal disinfectant at a concentration of 1,000ppm, with a focus on high-touch surfaces and equipment near the patient.^2,25 Additionally, for settings experiencing outbreaks or increased endemic rates, greater concentrations of up to 5,000ppm may be required. Research affirms that high concentrations of chlorine-based chemicals (5,000ppm) are more reliably effective against C. difficile spores in comparison to preparations with lower levels of chlorine, which have shown varied effectiveness in eradicating spores.²³ However, high concentrations also come with health and safety considerations, and their use needs to be risk assessed.⁶⁰

Notwithstanding a rise in certain ribotype resistance, the HSE favours the primary use of sodium hypochlorite (1,000ppm) over novel disinfection technology and products such as UV-light and hydrogen peroxide vapour disinfection, despite some reported benefits, due to factors such as added costs, time involved, and the lack of established high-quality evidence supporting their added benefit – a stance also reflected in current American CDI guidelines.^5,25,68,69 However, the latest UK CDI guidelines now recommend the additional use of hydrogen peroxide after usual sporicidal disinfectant for CDI.²⁷

Research indicates that personnel in environmental services possess a considerable degree of expertise concerning cleaning methodologies and recognise the significance of their position.⁷⁰ Health services, however, are strongly advised to incorporate assessments of cleaning efficacy and to create a framework for the advancement and training of cleaning staff to guarantee a high standard of environmental hygiene.^7,55,57 One study observed that while some ward areas maintained a consistent high standard of cleanliness, others repeatedly fell below acceptable levels.⁷¹

Additionally, cleaning effectiveness may be impacted by a variety of factors including who was entrusted with the responsibility, the inferred risk, and surface material.⁷¹ Furthermore, surfaces that were previously clean in this study were shown to become more contaminated after the cleaning process, in contrast to areas that had greater baseline colony-forming unit (CFU) counts.

However, as a result of cleaning, the clinical setting experienced an overall CFU decrease of almost 70 per cent. In a follow-up study, the authors audited the cleaning efficacy of both cleaning and nursing staff with a five-point cleaning bundle before and after implementing a teaching intervention and reported this initiative had a substantial positive influence on effective cleaning.⁷²

The benefits of adopting hospital-wide routine daily disinfection of all patient zones using a sporicidal agent can be reflected in a recent three-year multi-site initiative that yielded an impressive 50 per cent ongoing decrease in CDI rates.⁷³ Staff involved in this successful initiative were supported with education, structured performance surveillance, and feedback. The widespread adoption of such an initiative may not be favoured as it could possibly yield further disinfectant-resistant ribotypes in the long term.⁷⁴

However, the overall outcomes of collective recommended strategies for reducing CDI rates may be reflected during the Covid-19 pandemic, whereby CDI yearly cases dropped dramatically in Ireland, by an average of almost 18 per cent over both 2020 and 2021, in comparison to the annual mean of the five years prior.⁷⁵ This significant statistical decline was not exclusive to Ireland and has also been observed in other nations such as the US.^76,77 This decrease in C. difficile transmission may be attributable to the enhanced hand hygiene efforts and the extensive environmental cleaning and personal protective equipment utilisation that occurred throughout this period and, as such, the decline in infection rates may serve to help validate their collective efficacy in reducing C. difficile transmission.⁷⁶

Wastewater drainage points in healthcare facilities, including sinks, showers, and toilets are widely recognised as sources of pathogen contamination, and have been identified as the recognised source of transmission in many outbreaks.^78-81 Moreover, influencing factors and recognised routes exist through which microorganisms may be spread and transmitted from these sources, including droplet dispersal from sinks and toilet flushing, water flow and drainage rates, position of drains, and retrograde pipework.^82-89 An example of transmission risk from these sources is portrayed in a study which depicted that freshly contaminated toilets had the ability to continue to emit C. difficile spores via bioaerosols for up to 12 flushes, and via large droplets for as many as 24 flushes.⁹⁰

It has been highlighted that C. difficile spores can survive in healthcare drainage reservoirs and that they are rarely addressed by conventional hygiene practices, and therefore, can pose a significant hidden risk.⁹¹ Hospital wastewater biofilms serve an important function in microbial persistence within these systems and have been shown to be a critical hotspot for the distribution and transference of both mutations and antibiotic resistance inside these habitats via mobile genetic elements.^92-95 Concern already exists regarding the restricted range of antibiotics available for the management of CDI and the evolution of further resistance, including reports of identified plasmid-mediated resistance to metronidazole.^96,97

Recent research has detected significant quantities of toxigenic and nontoxigenic C. difficile isolates from biofilms and stagnate water samples in hospital sink and toilet traps (29%), and also in washer-disinfector machine traps (34%).⁹¹ Although these quantities diminished after the patient’s departure, they were found to survive for 13 to 19 days in up to 14 per cent of sites, which could potentially expose a large quantity of patients.

Additionally, contamination of toilet biofilms remained present after discharge in over half of CDI patient rooms. The authors in this study trialled a small-scale drain decolonising intervention involving one shower drain and two sinks that received treatment with a peracetic acid-based sporicidal disinfectant. Results revealed the treatment fully eliminated all CFUs in two out of the three sites, with a 99 per cent CFU reduction in the third. Though a small study, results are promising, and the authors urge the integration of such simplistic preventive measures into guidelines and cleaning protocols for these previously neglected reservoirs.

From a practical viewpoint, the Centers for Disease Control and Prevention (CDC) provide recommendations to help mitigate the potential for transmission from drains in healthcare settings, including discouraging the placement of patient belongings near basins and promoting the utilisation of toilet lids to prevent splash contamination when flushing.⁹⁸ Additionally, they also advise avoiding direct tap water discharge into drains to reduce splashing and that splash-reduction designs should be considered when fitting new basins.

Conclusion

In both hospital and community contexts, CDI presents a significant challenge for infection prevention and control, and imposes a significant burden on patients. Therefore, evidenced-based and effective strategies to contain and treat the pathogen are vital to tackle current trends of this ‘superbug’ across the globe. A combination of risk factor reduction, AMS, appropriate testing, and accurate diagnosis will greatly benefit management of CDI cases. Isolation of infected patients does carry risks and places added burdens on healthcare systems.

However, the literature would suggest that additional detection and isolation practices for asymptomatic carriers may further improve CDI rates, though further research may be required to validate such an approach before a universal agreement can be attained.

Additionally, environmental cleaning undoubtedly plays a central role in the reduction of CDI, and increased surveillance of cleaning efficacy – alongside revised and enhanced disinfection and cleaning procedures to tackle crucial sources of C. difficile on environmental surfaces – are required, in particular for underappreciated areas. Likewise, no doubt exists regarding the potential for infections posed by wastewater drainage points, and the management of these systems appears to be an essential component of holistic containment.

However, although no conclusive agreement has been reached, simple, practical interventions can contribute further to risk control, and most probably, a reduction in CDI infection rates.