Medical procedures and patient care activities may facilitate environmental dissemination of healthcare-associated pathogens such as methicillin-resistant Staphylococcus aureus (MRSA).

Observational cohort study of MRSA-colonized patients to determine the frequency of and risk factors for environmental shedding of MRSA during procedures and care activities in carriers with positive nares and/or wound cultures. Bivariate analyses were performed to identify factors associated with environmental shedding.

A Veterans Affairs hospital.

This study included 75 patients in contact precautions for MRSA colonization or infection.

Of 75 patients in contact precautions for MRSA, 55 (73%) had MRSA in nares and/or wounds and 25 (33%) had positive skin cultures. For the 52 patients with MRSA in nares and/or wounds and at least 1 observed procedure, environmental shedding of MRSA occurred more frequently during procedures and care activities than in the absence of a procedure (59 of 138, 43% vs 8 of 83, 10%; P < .001). During procedures, increased shedding occurred ≤0.9 m versus >0.9 m from the patient (52 of 138, 38% vs 25 of 138, 18%; P = .0004). Contamination occurred frequently on surfaces touched by personnel (12 of 38, 32%) and on portable equipment used for procedures (25 of 101, 25%). By bivariate analysis, the presence of a wound with MRSA was associated with shedding (17 of 29, 59% versus 6 of 23, 26%; P = .04).

Environmental shedding of MRSA occurs frequently during medical procedures and patient care activities. There is a need for effective strategies to disinfect surfaces and equipment after procedures.

To evaluate the efficacy of multiple ultraviolet (UV) light decontamination devices in a radiology procedure room.

Laboratory evaluation.

We compared the efficacy of 8 UV decontamination devices with a 4-minute UV exposure time in reducing recovery of methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), and Clostridium difficile spores on steel disk carriers placed at 5 sites on a computed tomography patient table. Analysis of variance was used to compare reductions for the different devices. A spectrometer was used to obtain irradiance measurements for the devices.

Four standard vertical tower low-pressure mercury devices achieved 2 log10CFU or greater reductions in VRE and MRSA and ~1 log10CFU reductions in C. difficile spores, whereas a pulsed-xenon device resulted in less reduction in the pathogens (P<.001). In comparison to the vertical tower low-pressure mercury devices, equal or greater reductions in the pathogens were achieved by 3 nonstandard low-pressure mercury devices that included either adjustable bulbs that could be oriented directly over the exam table, a robotic base allowing movement along the side of the table during operation, or 3 vertical towers operated simultaneously. The low-pressure mercury devices produced primarily UV-C light, whereas the pulsed-xenon device produced primarily UV-A and UV-B light. The time required to move the devices from the corner of the room and set up for operation varied from 18 to 59 seconds.

Many currently available UV devices could provide an effective and efficient adjunct to manual cleaning and disinfection in radiology procedure rooms.

To test the hypothesis that long-term care facility (LTCF) residents with Clostridium difficile infection (CDI) or asymptomatic carriage of toxigenic strains are an important source of transmission in the LTCF and in the hospital during acute-care admissions.

A 6-month cohort study with identification of transmission events was conducted based on tracking of patient movement combined with restriction endonuclease analysis (REA) and whole-genome sequencing (WGS).

Veterans Affairs hospital and affiliated LTCF.

The study included 29 LTCF residents identified as asymptomatic carriers of toxigenic C. difficile based on every other week perirectal screening and 37 healthcare facility-associated CDI cases (ie, diagnosis >3 days after admission or within 4 weeks of discharge to the community), including 26 hospital-associated and 11 LTCF-associated cases.

Of the 37 CDI cases, 7 (18·9%) were linked to LTCF residents with LTCF-associated CDI or asymptomatic carriage, including 3 of 26 hospital-associated CDI cases (11·5%) and 4 of 11 LTCF-associated cases (36·4%). Of the 7 transmissions linked to LTCF residents, 5 (71·4%) were linked to asymptomatic carriers versus 2 (28·6%) to CDI cases, and all involved transmission of epidemic BI/NAP1/027 strains. No incident hospital-associated CDI cases were linked to other hospital-associated CDI cases.

Our findings suggest that LTCF residents with asymptomatic carriage of C. difficile or CDI contribute to transmission both in the LTCF and in the affiliated hospital during acute-care admissions. Greater emphasis on infection control measures and antimicrobial stewardship in LTCFs is needed, and these efforts should focus on LTCF residents during hospital admissions.

Contaminated ice machines have been linked to transmission of pathogens in healthcare facilities.

To determine the frequency and sites of contamination of ice machines in multiple healthcare facilities and to investigate potential mechanisms of microorganism dispersal from contaminated ice machines to patients.

Multicenter culture survey and simulation study.

The study took place in 5 hospitals and 2 nursing homes in northeastern Ohio.

We cultured multiple sites on ice machines from patient care areas. To investigate potential mechanisms of microbial dispersal from contaminated ice machines, we observed the use of ice machines and conducted simulations using a fluorescent tracer and cultures.

Samples from 64 ice machines in the 5 hospitals and 2 nursing homes (range, 3–16 per facility) were cultured. Gram-negative bacilli and/or Candida spp were recovered from 100% of drain pans, 52% of ice and/or water chutes, and 72% of drain-pan grilles. During the operation of ice machines, ice often fell through the grille, resulting in splattering, with dispersal of contaminated water from the drain pan to the drain-pan grille, cups, and the hands of those using the ice machine. Contamination of the inner surface of the ice chute resulted in contamination of ice cubes exiting the chute.

Our findings demonstrate that ice machines in healthcare facilities are often contaminated with gram-negative bacilli and Candida species, and provide a potential mechanism by which these organisms may be dispersed. Effective interventions are needed to reduce the risk of dissemination of pathogenic organisms from ice machines.

Infect Control Hosp Epidemiol 2018;39:253–258

Contaminated hands of healthcare workers (HCWs) are an important source of transmission of healthcare-associated infections. Alcohol-based hand sanitizers, while effective, do not provide sustained antimicrobial activity. The objective of this study was to compare the immediate and persistent activity of 2 hand hygiene products (ethanol [61% w/v] plus chlorhexidine gluconate [CHG; 1.0% solution] and ethanol only [70% v/v]) when used in an intensive care unit (ICU).

Prospective, randomized, double-blinded, crossover study

Three ICUs at a large teaching hospital

In total, 51 HCWs involved in direct patient care were enrolled in and completed the study.

All HCWs were randomized 1:1 to either product. Hand prints were obtained immediately after the product was applied and again after spending 4–7 minutes in the ICU common areas prior to entering a patient room or leaving the area. The numbers of aerobic colony-forming units (CFU) were compared for the 2 groups after log transformation. Each participant tested the alternative product after a 3-day washout period.

On bare hands, use of ethanol plus CHG was associated with significantly lower recovery of aerobic CFU, both immediately after use (0.27 ± 0.05 and 0.88 ± 0.08 log10 CFU; P = .035) and after spending time in ICU common areas (1.81 ± 0.07 and 2.17 ± 0.05 log10 CFU; P<.0001). Both the antiseptics were well tolerated by HCWs.

In comparison to the ethanol-only product, the ethanol plus CHG sanitizer was associated with significantly lower aerobic bacterial counts on hands of HCWs, both immediately after use and after spending time in ICU common areas.

Clinicaltrials.gov identifier NCT02258412

Infect Control Hosp Epidemiol 2018;39:267–271

To determine the impact of an environmental disinfection intervention on the incidence of healthcare-associated Clostridium difficile infection (CDI).

A multicenter randomized trial.

In total,16 acute-care hospitals in northeastern Ohio participated in the study.

We conducted a 12-month randomized trial to compare standard cleaning to enhanced cleaning that included monitoring of environmental services (EVS) personnel performance with feedback to EVS and infection control staff. We assessed the thoroughness of cleaning based on fluorescent marker removal from high-touch surfaces and the effectiveness of disinfection based on environmental cultures for C. difficile. A linear mixed model was used to compare CDI rates in the intervention and postintervention periods for control and intervention hospitals. The primary outcome was the incidence of healthcare-associated CDI.

Overall, 7 intervention hospitals and 8 control hospitals completed the study. The intervention resulted in significantly increased fluorescent marker removal in CDI and non-CDI rooms and decreased recovery of C. difficile from high-touch surfaces in CDI rooms. However, no reduction was observed in the incidence of healthcare-associated CDI in the intervention hospitals during the intervention and postintervention periods. Moreover, there was no correlation between the percentage of positive cultures after cleaning of CDI or non-CDI rooms and the incidence of healthcare-associated CDI.

An environmental disinfection intervention improved the thoroughness and effectiveness of cleaning but did not reduce the incidence of healthcare-associated CDI. Thus, interventions that focus only on improving cleaning may not be sufficient to control healthcare-associated CDI.

Infect Control Hosp Epidemiol 2017;38:777–783

We investigated an increase in the incidence of healthcare-associated Clostridium difficile infection (CDI) that occurred following a change from a bleach disinfectant to a peracetic acid–based disinfectant.

To evaluate the efficacy of the peracetic acid–based disinfectant.

Laboratory-based product evaluation.

The commercial peracetic acid–based product is activated on site by mixing a small volume of concentrated hydrogen peroxide and peracetic acid present in a “SmartCap” reservoir with the remaining contents of the container. We measured concentrations of peracetic acid in newly activated and in-use product and determined the stability of nonactivated and activated product. We tested the efficacy of the product against C. difficile spores using the American Society for Testing and Materials standard quantitative carrier disk test method.

Measured concentrations of peracetic acid (50–800 parts per million [ppm]) were significantly lower than the level stated on the product label (1,500 ppm), and similar results were obtained for containers from multiple lot numbers and from another hospital. Product with peracetic acid levels below 600 ppm had significantly reduced activity against C. difficile spores. Peracetic acid concentrations were reduced markedly after storage of either activated or nonactivated product for several weeks. The Environmental Protection Agency confirmed the finding of low disinfectant levels and ordered discontinuation of sale of the product.

Use of a defective peracetic acid–based surface disinfectant may have contributed to an increase in healthcare-associated CDI. Our findings highlight the importance of evaluating the efficacy of liquid disinfectants in healthcare settings.

Infect Control Hosp Epidemiol 2017;38:300–305