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To quantify the association between admission to an intensive care unit (ICU) room most recently occupied by a patient positive for extended-spectrum β-lactamase (EBSL)-producing gram-negative bacteria and acquisition of infection or colonization with that pathogen.
Retrospective cohort study.
Setting and Patients.
The study included patients admitted to medical and surgical ICUs of an academic medical center between September 1, 2001, and June 30, 2009.
Perianal surveillance cultures were obtained at admission to the ICU, weekly, and at discharge from the ICU. Patients were included if they had culture results that were negative for ESBL-producing gram-negative bacteria at ICU admission and had an ICU length of stay longer than 48 hours. Pulsed-field gel electrophoresis (PFGE) was performed on ESBL-positive isolates from patients who acquired the same bacterial species (eg, Klebsiella species or Escherichia coli) as the previous room occupant.
Among 9, 371 eligible admissions (7, 651 unique patients), 267 (3%) involved patients who acquired an ESBL-producing pathogen in the ICU; of these patients, 32 (12%) were hospitalized in a room in which the prior occupant had been positive for ESBL. Logistic regression results suggested that the prior occupant's ESBL status was not significantly associated with acquisition of an ESBL-producing pathogen (adjusted odds ratio, 1.39 [95% confidence interval, 0.94-2.08]) after adjusting for colonization pressure and antibiotic exposure in the ICU. PFGE results suggested that 6 (18%) of 32 patients acquired a bacterial strain that was the same as or closely related to the strain obtained from the prior occupant.
These data suggest that environmental contamination may not play a substantial role in the transmission of ESBL-producing pathogens among ICU patients. Intensifying environmental decontamination may be less effective than other interventions in preventing transmission of ESBL-producing pathogens.
Effective disinfection of hospital rooms after discharge of patients with Clostridium difficile infection (CDI) is necessary to prevent transmission. We evaluated the impact of sequential cleaning and disinfection interventions by culturing high-touch surfaces in CDI rooms after cleaning.
A Veterans Affairs hospital.
During a 21-month period, 3 sequential tiered interventions were implemented: (1) fluorescent markers to provide monitoring and feedback on thoroughness of cleaning facility-wide, (2) addition of an automated ultraviolet radiation device for adjunctive disinfection of CDI rooms, and (3) enhanced standard disinfection of CDI rooms, including a dedicated daily disinfection team and implementation of a process requiring supervisory assessment and clearance of terminally cleaned CDI rooms. To determine the impact of the interventions, cultures were obtained from CDI rooms after cleaning and disinfection.
The fluorescent marker intervention improved the thoroughness of cleaning of high-touch surfaces (from 47% to 81% marker removal; P < .0001). Relative to the baseline period, the prevalence of positive cultures from CDI rooms was reduced by 14% (P = .024), 48% (P>.001), and 89% (P = .006) with interventions 1, 2, and 3, respectively. During the baseline period, 67% of CDI rooms had positive cultures after disinfection, whereas during interventions periods 1, 2, and 3 the percentages of CDI rooms with positive cultures after disinfection were reduced to 57%, 35%, and 7%, respectively.
An intervention that included formation of a dedicated daily disinfection team and implementation of a standardized process for clearing CDI rooms achieved consistent CDI room disinfection. Culturing of CDI rooms provides a valuable tool to drive improvements in environmental disinfection.
To determine the effectiveness of an automated ultraviolet-C (UV-C) emitter against vancomycin-resistant enterococci (VRE), Clostridium difficile, and Acinetobacter spp. in patient rooms.
Prospective cohort study.
Two tertiary care hospitals.
Convenience sample of 39 patient rooms from which a patient infected or colonized with 1 of the 3 targeted pathogens had been discharged.
Environmental sites were cultured before and after use of an automated UV-C-emitting device in targeted rooms but before standard terminal room disinfection by environmental services.
In total, 142 samples were obtained from 27 rooms of patients who were colonized or infected with VRE, 77 samples were obtained from 10 rooms of patients with C. difficile infection, and 10 samples were obtained from 2 rooms of patients with infections due to Acinetobacter. Use of an automated UV-C-emitting device led to a significant decrease in the total number of colony-forming units (CFUs) of any type of organism (1.07 log10 reduction; P < .0001), CFUs of target pathogens (1.35 log10 reduction; P < .0001), VRE CFUs (1.68 log10 reduction; P < .0001), and C. difficile CFUs (1.16 log10 reduction; P < .0001). CFUs of Acinetobacter also decreased (1.71 log10 reduction), but the trend was not statistically significant P = .25). CFUs were reduced at all 9 of the environmental sites tested. Reductions similarly occurred in direct and indirect line of sight.
Our data confirm that automated UV-C-emitting devices can decrease the bioburden of important pathogens in real-world settings such as hospital rooms.
Individually packaged sterile supply items may become contaminated and act as vectors for nosocomial transmission of multidrug-resistant organisms (MDROs). Thus, many hospitals have a policy to dispose of these unused, packaged supply items at patient discharge from the hospital, which has considerable cost implications. We evaluated the frequency of contamination of these items, the efficacy of hydrogen peroxide vapor (HPV) in disinfecting them, and costs associated with discarded supplies.
A pilot study was performed in the rooms of 20 patients known to be colonized or infected with vancomycin-resistant enterococci (VRE), and a follow-up study was performed in an additional 20 rooms of patients under precautions for various MDROs in 6 high-risk units. Five pairs of supply items were selected. One item of each pair was sampled without exposure to HPV, and the other was sampled after HPV exposure. The cost of discarded supplies was calculated by examining stock lists of supplies stored on the study units.
Seven (7%) of 100 items were contaminated with VRE in the pilot study, and 9 (9%) of 100 items were contaminated with MDROs in the follow-up study. None of the items were contaminated after exposure to HPV (P < .02 in both the pilot and the follow-up study). The annual cost of supplies discarded at patient hospital discharge was $387,055. This figure does not include the cost of waste disposal and is therefore likely to be an underestimation of the financial burden.
HPV effectively disinfected the packaging of supply items, which could generate considerable financial and environmental benefits.
Healthcare-acquired infections (HAIs) cause substantial patient morbidity and mortality. Items in the environment harbor microorganisms that may contribute to HAIs. Reduction in surface bioburden may be an effective strategy to reduce HAIs. The inherent biocidal properties of copper surfaces offer a theoretical advantage to conventional cleaning, as the effect is continuous rather than episodic. We sought to determine whether placement of copper alloy-surfaced objects in an intensive care unit (ICU) reduced the risk of HAI.
Intention-to-treat randomized control trial between July 12, 2010, and June 14, 2011.
The ICUs of 3 hospitals.
Patients presenting for admission to the ICU.
Patients were randomly placed in available rooms with or without copper alloy surfaces, and the rates of incident HAI and/or colonization with methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus (VRE) in each type of room were compared.
The rate of HAI and/or MRSA or VRE colonization in ICU rooms with copper alloy surfaces was significantly lower than that in standard ICU rooms (0.071 vs 0.123; P = .020). For HAI only, the rate was reduced from 0.081 to 0.034 (P = .013).
Patients cared for in ICU rooms with copper alloy surfaces had a significantly lower rate of incident HAI and/or colonization with MRSA or VRE than did patients treated in standard rooms. Additional studies are needed to determine the clinical effect of copper alloy surfaces in additional patient populations and settings.
To determine whether enhanced daily cleaning would reduce contamination of healthcare worker (HCW) gowns and gloves with methicillin-resistant Staphylococcus aureus (MRSA) or multidrug-resistant Acinetobacter baumannii (MDRAB).
A cluster-randomized controlled trial.
Four intensive care units (ICUs) in an urban tertiary care hospital.
ICU rooms occupied by patients colonized with MRSA or MDRAB.
Extra enhanced daily cleaning of ICU room surfaces frequently touched by HCWs.
A total of 4,444 cultures were collected from 132 rooms over 10 months. Using fluorescent dot markers at 2,199 surfaces, we found that 26% of surfaces in control rooms were cleaned and that 100% of surfaces in experimental rooms were cleaned (P < .001). The mean proportion of contaminated HCW gowns and gloves following routine care provision and before leaving the rooms of patients with MDRAB was 16% among control rooms and 12% among experimental rooms (relative risk, 0.77 [95% confidence interval, 0.28-2.11]; P = .23). For MRSA, the mean proportions were 22% and 19%, respectively (relative risk, 0.89 [95% confidence interval, 0.50-1.53]; P = .16).
Intense enhanced daily cleaning of ICU rooms occupied by patients colonized with MRSA or MDRAB was associated with a nonsignificant reduction in contamination of HCW gowns and gloves after routine patient care activities. Further research is needed to determine whether intense environmental cleaning will lead to significant reductions and fewer infections.
Specification of appropriate personal protective equipment for respiratory protection against influenza is somewhat controversial. In a clinical environment, N95 filtering facepiece respirators (FFRs) are often recommended for respiratory protection against infectious aerosols. This study evaluates the ability of N95 FFRs to capture viable H1N1 influenza aerosols.
Five N95 FFR models were challenged with aerosolized viable H1N1 influenza and inert polystyrene latex particles at continuous flow rates of 85 and 170 liters per minute. Virus was assayed using Madin-Darby canine kidney cells to determine the median tissue culture infective dose (TCID50). Aerosols were generated using a Collison nebulizer containing H1N1 influenza virus at 1 × 108 TCID50/mL. To determine filtration efficiency, viable sampling was performed upstream and downstream of the FFR.
N95 FFRs filtered 0.8-μm particles of both H1N1 influenza and inert origins with more than 95% efficiency. With the exception of 1 model, no statistically significant difference in filtration performance was observed between influenza and inert particles of similar size. Although statistically significant differences were observed for 2 models when comparing the 2 flow rates, the differences have no significance to protection.
This study empirically demonstrates that a National Institute for Occupational Safety and Health-approved N95 FFR captures viable H1N1 influenza aerosols as well as or better than its N95 rating, suggesting that a properly fitted FFR reduces inhalation exposure to airborne influenza virus. This study also provides evidence that filtration efficiency is based primarily on particle size rather than the nature of the particle's origin.
To investigate the distribution of hospital pathogens within general and critical care ward environments and to determine the most significant bacterial reservoirs within each ward type.
Prospective 4-month microbiological survey.
The intensive care unit (ICU) and gastrointestinal (GI) surgical ward of a London teaching hospital.
Sampling was conducted in and around the bed space of 166 different patients (99 in the ICU and 67 in the GI ward).
Conventional agar contact methodology was used to sample 123 predetermined sites twice a week for 17 weeks. Sixty-one surfaces were located within the ICU, and 62 were located within the GI ward. Each surface was located within a theoretical zone of increasing distance from the patient. Aerobic colony counts were determined, and confirmatory testing was conducted on all presumptive pathogens.
Regardless of ward type, surfaces located closest to the patient, specifically those associated with the bed (side rails, bed control, and call button), were the most heavily contaminated. Elsewhere, the type of surfaces contaminated differed with ward type. In the ICU, bacteria were most likely to be on surfaces that were regularly touched by healthcare workers (eg, telephones and computer keyboards). In the GI ward, where the patients were mobile, the highest numbers of bacteria (including potential nosocomial pathogens) were on surfaces that were mainly touched by patients, particularly their toilet and shower facilities.
In terms of cleaning, a hospital should not be considered a single entity. Different ward types should be treated as separate environments, and cleaning protocols should be adjusted accordingly.
We aimed to determine the association between the presence of Acinetobacter baumannii in patient rooms and the carrier status of the occupants. Fifty-six (39%) of 143 rooms with A. baumannii– positive patients had results positive for A. baumannii. Only 49 (10%) of 485 rooms with A. baumannii-negative patients were positive (odds ratio, 5.72 [95% confidence interval, 3.66–8.96]; P < .0001). Clinical and environmental isolates shared pulsed-field gel electrophoresis patterns.
A new activated hydrogen peroxide wipe disinfectant was used to disinfect 10 high-touch surfaces in 72 patient rooms. After cleaning, 99% of surfaces yielded less than 2.5 colony-forming units/cm2, 75% yielded no growth, and 70% yielded adenosine triphosphate counts of less than 250 relative light units. The new disinfectant was highly effective.
Education and passive observation resulted in a significant improvement in housekeeper disinfection of nontoxigenic Clostridium difficile spores artificially inoculated onto surfaces in C. difficile infection rooms. A further significant reduction occurred with direct supervision and real-time feedback, suggesting that optimal disinfection is achieved by working closely with housekeepers.
We tested the ability of an ultraviolet C (UV-C)–reflective wall coating to reduce the time necessary to decontaminate a room using a UV-C-emitting device (Tru-D SmartUVC). The reflective wall coating provided the following time reductions for decontamination: for methicillin-resistant Staphylococcus aureus, from 25 minutes 13 seconds to 5 minutes 3 seconds (P < .05), and for Clostridium difficile spores, from 43 minutes 42 seconds to minutes 24 seconds (P < .05).
Cleaning is an effective way to lower the bacterial burden (BB) on surfaces and minimize the infection risk to patients. However, BB can quickly return. Copper, when used to surface hospital bed rails, was found to consistently limit surface BB before and after cleaning through its continuous antimicrobial activity.
Contamination of inanimate surfaces contributes to the transmission of healthcare-associated infection, a phenomenon that is well documented for methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). The high rate of skin colonization with these bacteria among healthcare workers increases the risk of cross contamination via high-touch surfaces. Since gram-negative bacteria are believed to survive poorly on surfaces, their role in the transmission of infection has not been investigated as widely. Extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-PE) are widespread and endemic in nosocomial settings. Given the increasing prevalence of infections involving ESBL-PE, the role of the environment in ESBL-PE transmission should be explored. This study reports the evaluation of 2 ESBL-PE recovery methods from typical hospital surface materials and their application for recovery of ESBL-PE adjacent to an ESBL-positive patient.
Environmental contamination of hospital rooms is well recognized as a reservoir for highly resistant nosocomial pathogens such as methicillin-resistant Staphylococcus aureu (MRSA) and vancomycin-resistant Enterococcus (VRE), which can be transferred to patients through contact with healthcare providers and contaminated surfaces. Numerous studies dedicated to environmental cleaning and disinfection have found promising results with several novel technologies, including vaporized hydrogen peroxide and ultraviolet over-head lighting or wands. We conducted a pilot study of one such device, the Sterilray Disinfection Wand (Healthy Environment Innovations), a handheld ultraviolet (UV) room decontamination wand. The Sterilray device claims to generate UV radiation in the far-UV spectrum (185-230 nm), resulting in the rapid killing of contaminant bacteria. The goal of this pilot was to collect preliminary data on the efficacy of this device in reducing surface contamination, particularly of common nosocomial pathogens, in an active hospital setting.
Measurement of adenosine triphosphate (ATP) using portable bioluminometers has been adapted from the food manufacturing sector, and it has been suggested that it could be used as an indicator of surface soiling or cleanliness in hospital settings. Some healthcare authorities are considering the use of portable ATP bioluminometers as a tool for standard setting for surface cleanliness to improve cleaning standards. Central to this approach is the use of a commonly accepted level of detected ATP—expressed as relative light units (RLUs)—that may be used as a surrogate for underlying soiling, including the presence of pathogenic microorganisms.
It has been demonstrated that improvements can be made to cleaning processes with fluorescent markers through a simpler approach that provides a qualitative efficiency measurement of the cleaning process. Measurement of surface hygiene using ATP bioluminometers is thought to provide a more quantitative surrogate of surface cleanliness.
Over the past decade, large outbreaks of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) infections have occurred in correctional facilities across the country. Although many have been managed with aggressive interventions, response to standard infection control procedures has been variable, highlighting our incomplete understanding of staphylococcal transmission in this setting. Environmental contamination has recently emerged as a possible target for novel prevention and control strategies. This study sought to characterize the relationship between environmental contamination and clinical infection in this vulnerable population.
We conducted a case-control study of S. aureus environmental contamination at 2 New York State (NYS) maximum security prisons: Sing Sing (men) and Bedford Hills (women).