What is the primary mode of transmission for Clostridioides difficile (C. diff)?

C. difficile Transmission

C. difficile is primarily transmitted through the fecal-oral route via spores that contaminate healthcare environments and persist on surfaces, with direct and indirect contact being the main modes of transmission. 1

Primary Transmission Mechanisms

Spore-Mediated Transmission

• C. difficile produces spores that are highly resistant to standard hospital disinfectants and can survive for months in the environment 1
• These spores contaminate surfaces including toilets, commodes, floors, bed rails, call buttons, sinks, and over bed tables 1
• Environmental contamination is highest in rooms of patients with active CDI (9-50% of rooms) compared to asymptomatic carriers (8-30%) 1

Person-to-Person Transmission

• Healthcare personnel's hands frequently become contaminated (14-59% when gloves are not worn) after caring for CDI patients 1
• Patient hands can also become contaminated with C. difficile at a rate of 32%, potentially leading to self-infection or environmental contamination 1
• Transmission commonly occurs via healthcare workers who fail to practice proper hand hygiene between patient contacts 1

Risk Factors for Transmission

• Shared hospital rooms (17% CDI acquisition in double rooms vs. 7% in single rooms) 1
• Contact with contaminated medical equipment (commodes, blood pressure cuffs, thermometers, stethoscopes) 1
• Stool incontinence in CDI patients (increases environmental contamination) 1
• Inadequate terminal cleaning of rooms previously occupied by CDI patients 1

Prevention of Transmission

Isolation and Contact Precautions

• Place CDI patients in private rooms with dedicated toilets 1
• Use contact precautions (gloves and gowns) when entering rooms of CDI patients 1
• Continue contact precautions for at least 48 hours after diarrhea resolves 1
• Place patients with suspected CDI on preemptive contact precautions pending test results 1

Hand Hygiene

• In routine settings: Perform hand hygiene before and after patient contact with either soap and water or alcohol-based products 1
• In outbreak or hyperendemic settings: Use soap and water preferentially over alcohol-based products (soap and water is more effective at removing spores) 1
• Always use soap and water when there is direct contact with feces or likely fecal contamination 1

Environmental Cleaning

• Use disposable patient equipment when possible 1
• Ensure reusable equipment is thoroughly cleaned with sporicidal disinfectants 1
• Perform terminal room cleaning with sporicidal agents, especially during outbreaks or when there are repeated cases in the same room 1
• Encourage patients to wash hands and shower to reduce spore burden on skin 1

Special Considerations

• C. difficile is increasingly causing community-acquired infections, not just healthcare-associated ones 2
• Cohorting patients with CDI should only be done if private rooms are unavailable, and only with other CDI patients (not with patients with other multidrug-resistant organisms) 1
• Patient bathing, particularly showering rather than bed bathing, can decrease skin contamination with C. difficile 1

Common Pitfalls in Preventing Transmission

• Relying solely on alcohol-based hand sanitizers during outbreaks (they don't kill spores effectively) 1
• Failing to implement preemptive contact precautions for suspected cases (average test result delay is 2.07 days) 1
• Inadequate cleaning of shared medical equipment between patient use 1
• Discontinuing contact precautions too early (before 48 hours after diarrhea resolution) 1
• Poor compliance with glove and gown use when entering rooms of CDI patients 1

By implementing comprehensive infection control measures targeting these transmission pathways, healthcare facilities can significantly reduce the spread of C. difficile and associated morbidity and mortality.