Evaluation of an automated ultraviolet radiation device for decontamination of Clostridium difficile and other healthcare-associated pathogens in hospital rooms

<p>Abstract</p> <p>Background</p> <p>Environmental surfaces play an important role in transmission of healthcare-associated pathogens. There is a need for new disinfection methods that are effective against <it>Clostridium difficile </it>spores, but also safe, rapid, and automated.</p> <p>Methods</p> <p>The Tru-D™ Rapid Room Disinfection device is a mobile, fully-automated room decontamination technology that utilizes ultraviolet-C irradiation to kill pathogens. We examined the efficacy of environmental disinfection using the Tru-D device in the laboratory and in rooms of hospitalized patients. Cultures for <it>C. difficile</it>, methicillin-resistant <it>Staphylococcus aureus </it>(MRSA), and vancomycin-resistant <it>Enterococcus </it>(VRE) were collected from commonly touched surfaces before and after use of Tru-D.</p> <p>Results</p> <p>On inoculated surfaces, application of Tru-D at a reflected dose of 22,000 μWs/cm²for ~45 minutes consistently reduced recovery of <it>C. difficile </it>spores and MRSA by >2-3 log₁₀colony forming units (CFU)/cm²and of VRE by >3-4 log₁₀CFU/cm². Similar killing of MRSA and VRE was achieved in ~20 minutes at a reflected dose of 12,000 μWs/cm², but killing of <it>C. difficile </it>spores was reduced. Disinfection of hospital rooms with Tru-D reduced the frequency of positive MRSA and VRE cultures by 93% and of <it>C. difficile </it>cultures by 80%. After routine hospital cleaning of the rooms of MRSA carriers, 18% of sites under the edges of bedside tables (i.e., a frequently touched site not easily amenable to manual application of disinfectant) were contaminated with MRSA, versus 0% after Tru-D (<it>P </it>< 0.001). The system required <5 minutes to set up and did not require continuous monitoring.</p> <p>Conclusions</p> <p>The Tru-D Rapid Room Disinfection device is a novel, automated, and efficient environmental disinfection technology that significantly reduces <it>C. difficile</it>, VRE and MRSA contamination on commonly touched hospital surfaces.</p

Multihospital Outbreak of Clostridium difficile Infection, Cleveland, Ohio, USA

To determine whether a multihospital Clostridium difficile outbreak was associated with epidemic strains and whether use of particular fluoroquinolones was associated with increased infection rates, we cultured feces from C. difficile–infected patients. Use of fluoroquionolones with enhanced antianaerobic activity was not associated with increased infection rates

Hospital-acquired Clostridium difficile-associated disease in the intensive care unit setting: epidemiology, clinical course and outcome

<p>Abstract</p> <p>Background</p> <p><it>Clostridium difficile</it>-associated disease (CDAD) is a serious nosocomial infection, however few studies have assessed CDAD outcome in the intensive care unit (ICU). We evaluated the epidemiology, clinical course and outcome of hospital-acquired CDAD in the critical care setting.</p> <p>Methods</p> <p>We performed a historical cohort study on 58 adults with a positive <it>C. difficile </it>cytotoxin assay result occurring in intensive care units.</p> <p>Results</p> <p>Sixty-two percent of patients had concurrent infections, 50% of which were bloodstream infections. The most frequently prescribed antimicrobials prior to CDAD were anti-anaerobic agents (60.3%). Septic shock occurred in 32.8% of CDAD patients. The in-hospital mortality was 27.6%. Univariate analysis revealed that SOFA score, at least one organ failure and age were predictors of mortality. Charlson score ≥3, gender, concurrent infection, and number of days with diarrhea before a positive <it>C. difficile </it>toxin assay were not significant predictors of mortality on univariate analysis. Independent predictors for death were SOFA score at infection onset (per 1-point increment, OR 1.40; CI95 1.13–1.75) and age (per 1-year increment, OR 1.10; CI95 1.02–1.19).</p> <p>Conclusion</p> <p>In ICU patients with CDAD, advanced age and increased severity of illness at the onset of infection, as measured by the SOFA score, are independent predictors of death.</p

In Vitro Killing of Nosocomial Pathogens by Acid and Acidified Nitrite

Exposure to pH 1 or 2 buffers or acidic gastric contents resulted in the killing of vancomycin-resistant Enterococcus sp., Klebsiella pneumoniae, Staphylococcus aureus, and Candida glabrata but not Clostridium difficile spores. Nitrite enhanced killing under acidic conditions, but significant killing of C. difficile spores required nitrite concentrations above usual physiological levels

Contamination of Hospital Curtains With Healthcare-Associated Pathogens

In a culture survey, we found that 42% of hospital privacy curtains were contaminated with vancomycin-resistant enterococci, 22% with methicillin-resistant Staphylococcus aureus, and 4% with Clostridium difficile. Hand imprint cultures demonstrated that these pathogens were easily acquired on hands. Hospital curtains are a potential source for dissemination of healthcare-associated pathogens. 2008; 29:1074-1076 Recent studies suggest that contaminated environmental surfaces may play an important role in transmission of healthcare-associated pathogens. Infect Control Hosp Epidemiol 1-6 For example, we found that vancomycin-resistant enterococci (VRE) and Staphylococcus aureus were frequently acquired on hands after contact with contaminated surfaces in patients&apos; rooms. 2 Boyce et al. 3 similarly demonstrated that nurses frequently acquired methicillin-resistant S. aureus (MRSA) on gloves after touching surfaces near colonized patients. In a medical intensive care unit, Hayden et al. methods The Cleveland Veterans Affairs Medical Center is a 202-bed acute care hospital. At the time of the study, active surveillance for MRSA carriage was performed, and colonized or infected patients were placed under contact precautions. Patients with C. difficile-associated disease were placed under contact precautions until they completed treatment and the diarrhea resolved. No active surveillance was performed for VRE, and patients colonized or infected with VRE were not placed under contact precautions. In January 2008, samples for culture of VRE, MRSA, and C. difficile were collected from 50 privacy curtains on 7 wards, including 4 medical wards, a spinal cord injury ward, and medical and surgical intensive care units. The privacy curtains used in the hospital were manufactured by American Drapemasters and Caldwell&apos;s. The curtains were cleaned once every 4 months or if they were noted to be visibly soiled. It was noted if the samples were collected from an isolation room. A 25-cm 2 area on the lateral edge of the middle section of the curtain was sampled for culture, because this is the area that HCWs most often contact with their hands when opening or closing the curtains. First, hand imprint cultures for VRE, MRSA, and C. difficile were performed: sterile gloves were donned and the curtain was gripped to simulate the motion of opening and closing the curtain; the gloved fingertips and thumb of the hand were then imprinted onto selective agar plates. For VRE, MRSA, and C. difficile, selective media included Enterococcosel agar (Becton Dickinson) containing 20 mg of vancomycin per milliliter; CHROMagar (Becton Dickinson) containing 6 mg of cefoxitin per milliliter; and cycloserine-cefoxitin-fructose agar, containing 0.1% taurocholic acid and lysozyme at a concentration of 5 mg/mL (CCFA-TAL). Second, direct plating cultures for VRE and MRSA were performed by applying premoistened, sterile cotton-tipped swabs to a 25-cm 2 area, followed by direct plating of the swab specimens onto selective agar. Direct plating cultures were performed to provide an approximation of the concentration of organisms on the curtains. Finally, broth enrichment cultures for VRE and C. difficile were performed: sterile gloves were donned and used to wipe the same area with a premoistened, sterile 2 x 2 cm gauze pad, which was then placed in a sterile specimen cup. Broth enrichment cultures were not performed for MRSA, because preliminary studies indicated that the yield was similar for broth enrichment and direct plating cultures. Plates were incubated at 37ЊC for 48 hours. For VRE and MRSA, colonies with unique morphology were subjected to identification and susceptibility testing in accordance with Clinical Laboratories Standards Institute guidelines. 11 Broth enrichment cultures for C. difficile were performed as described elsewhere