The Most Effective C. Difficile Prevention Strategies

Anna K. Barker, PhD, University of Wisconsin-Madison

Anna K. Barker, PhD

Screenings and daily cleanings with sporicidal disinfectant are effective strategies for Clostridium difficile (C. difficile) prevention in hospital settings, according to a recent study.

Researchers from the University of Wisconsin-Madison studied a model of C. difficile transmission in a 200-bed hospital setting in order to evaluate the differences between several interventions and intervention bundles used. The researchers wrote that the clinical and economic impacts of C. difficile continue to worsen despite intensified efforts to decrease transmission. Many of these transmission prevention bundles vary in terms of strength of evidence and effectiveness, they added. That led to the development of their transmission model.

The study authors included 4 agent types in their research: patients, visitors, nurses and physicians. There were also 9 nine total infection control interventions introduced to the model: 4 of which were focused on the hospital and 5 centered around the patients.

The researchers learned that hospital-onset C. difficile infection (HO-CDI) decreased after the implementation of enhanced and ideal levels of 6 of the observed interventions: daily and terminal cleaning, health care worker hand hygiene, patient hand hygiene, screening at admission, and patient transfer reduction.

The most effective enhanced single intervention in reducing HO-CDI was screening at admission, which decreased infection cases by 5.13 per 10,000 patient-days, according to the researchers. This was closely followed by the second-most effective intervention; daily cleaning with a sporicidal disinfectant reduced HO-CDI by 2.48 per 10,000 patient-days. These correspond to 68.9% and 35.7% reductions in HO-CDI, they wrote.

Interventions such as visitor hand hygiene and visitor contact precautions did not reduce HO-CDI or asymptomatic colonization compared to baseline numbers, the investigators said. Besides those 2, health care worker hand hygiene precautions were the least effective strategy in preventing hospital-onset colonization and infection, the report continued.

Timing of each of the interventions mattered, too. The strategies ranged between 0—18.8% additional reduction in HO-CDI. Health care worker and patient hand hygiene interventions demonstrated the greatest increases in compliance among the interventions.

The patient-centered bundle was a focus of the study. The 2-pronged approach included screening at admission, patient hand hygiene and reducing intra- and inter-ward room transfers. This strategy was more effective than the 2-pronged patient and health care worker hand hygiene bundle, the researchers learned. Nearly an 8% increase was observed when patient hand hygiene was added to the health care worker hand hygiene intervention alone, though.

"The most surprising observation was how effective an isolated 2-pronged infection control bundle was at reducing the rates of HO-CDI," study author Anna K. Barker, PhD, told MD Magazine. "Current practice in many hospitals is to implement several infection control interventions simultaneously, in an attempt to reduce HO-CDI rates. However, our results show that the rate of hospital-acquired C. difficile infection can be reduced dramatically by focusing on just 2 high-yield strategies, daily cleaning and asymptomatic screening at admission."

The main sources of C. difficile transmission were the nursing staff and the environment, responsible for as much as 40% of the exposures at baseline conditions, the investigators reported. Patient-to-patient transmission was minimal, accounting for only 0.24% of exposures.

"The implications of these findings provides evidence for hospitals to focus their infection control efforts on a smaller number of strategies than is currently the norm," Barker continued. "Another surprising finding was the role for patient hand hygiene as an adjunct to more traditional healthcare worker hand hygiene interventions. To date, few institutions have focused on hand hygiene of patients' themselves, which we have shown has potential as an untapped area in the reduction of hospital-acquired infections."

The study, titled "Interventions to Reduce the Incidence of Hospital-Onset Clostridium difficile Infection: An Agent-Based Modeling Approach to Evaluate Clinical Effectiveness in Adult Acute Care Hospitals," was published in the journal Clinical Infectious Diseases.