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In a randomized trial, patients wearing slippers whenever out of bed transferred bacteriophage MS2 from hospital room floors to patients and surfaces significantly less often than controls not provided with slippers. Wearing slippers could provide a simple means to reduce the risk for acquisition of healthcare-associated pathogens from contaminated floors.
For 40 patients with methicillin-resistant Staphylococcus aureus (MRSA) colonization, fist bump and elbow bump greetings resulted in frequent transfer of MRSA (25% vs 15%, respectively), but significantly fewer colonies were transferred via the elbow bump. Noncontact greetings should be encouraged to reduce the risk of transfer of healthcare-associated pathogens.
A single spray application of a continuously active disinfectant on portable equipment resulted in significant reductions in aerobic colony counts over 7 days and in recovery of Staphylococcus aureus and enterococci: 3 of 93 cultures (3%) versus 11 of 97 (11%) and 20 of 97 (21%) in quaternary ammonium disinfectant and untreated control groups, respectively.
To assess the potential for contamination of personnel, patients, and the environment during use of contaminated N95 respirators and to compare the effectiveness of interventions to reduce contamination.
Simulation study of patient care interactions using N95 respirators contaminated with a higher and lower inocula of the benign virus bacteriophage MS2.
In total, 12 healthcare personnel performed 3 standardized examinations of mannequins including (1) control with suboptimal respirator handling technique, (2) improved technique with glove change after each N95 contact, and (3) control with 1-minute ultraviolet-C light (UV-C) treatment prior to donning. The order of the examinations was randomized within each subject. The frequencies of contamination were compared among groups. Observations and simulations with fluorescent lotion were used to assess routes of transfer leading to contamination.
With suboptimal respirator handling technique, bacteriophage MS2 was frequently transferred to the participants, mannequin, and environmental surfaces and fomites. Improved technique resulted in significantly reduced transfer of MS2 in the higher inoculum simulations (P < .01), whereas UV-C treatment reduced transfer in both the higher- and lower-inoculum simulations (P < .01). Observations and simulations with fluorescent lotion demonstrated multiple potential routes of transfer to participants, mannequin, and surfaces, including both direct contact with the contaminated respirator and indirect contact via contaminated gloves.
Reuse of contaminated N95 respirators can result in contamination of personnel and the environment even when correct technique is used. Decontamination technologies, such as UV-C, could reduce the risk for transmission.
To investigate the timing and routes of contamination of the rooms of patients newly admitted to the hospital.
Observational cohort study and simulations of pathogen transfer.
A Veterans’ Affairs hospital.
Patients newly admitted to the hospital with no known carriage of healthcare-associated pathogens.
Interactions between the participants and personnel or portable equipment were observed, and cultures of high-touch surfaces, floors, bedding, and patients’ socks and skin were collected for up to 4 days. Cultures were processed for Clostridioides difﬁcile, methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant enterococci (VRE). Simulations were conducted with bacteriophage MS2 to assess plausibility of transfer from contaminated floors to high-touch surfaces and to assess the effectiveness of wearing slippers in reducing transfer.
Environmental cultures became positive for at least 1 pathogen in 10 (59%) of the 17 rooms, with cultures positive for MRSA, C. difficile, and VRE in the rooms of 10 (59%), 2 (12%), and 2 (12%) participants, respectively. For all 14 instances of pathogen detection, the initial site of recovery was the floor followed in a subset of patients by detection on sock bottoms, bedding, and high-touch surfaces. In simulations, wearing slippers over hospital socks dramatically reduced transfer of bacteriophage MS2 from the floor to hands and to high-touch surfaces.
Floors may be an underappreciated source of pathogen dissemination in healthcare facilities. Simple interventions such as having patients wear slippers could potentially reduce the risk for transfer of pathogens from floors to hands and high-touch surfaces.
Gloves and gowns are used during patient care to reduce contamination of personnel and prevent pathogen transmission.
To determine whether the use of gowns adds a substantial benefit over gloves alone in preventing patient-to-patient transfer of a viral DNA surrogate marker.
In total, 30 source patients had 1 cauliflower mosaic virus surrogate marker applied to their skin and clothing and a second to their bed rail and bedside table. Personnel caring for the source patients were randomized to wear gloves, gloves plus cover gowns, or no barrier. Interactions with up to 7 subsequent patients were observed, and the percentages of transfer of the DNA markers were compared among the 3 groups.
In comparison to the no-barrier group (57.8% transfer of 1 or both markers), there were significant reductions in transfer of the DNA markers in the gloves group (31.1% transfer; odds ratio [OR], 0.16; 95% confidence interval [CI], 0.02-0.73) and the gloves-plus-gown group (25.9% transfer; OR, 0.11; 95% CI, 0.01–0.51). The addition of a cover gown to gloves during the interaction with the source patient did not significantly reduce the transfer of the DNA marker (P = .53). During subsequent patient interactions, transfer of the DNA markers was significantly reduced if gloves plus gowns were worn and if hand hygiene was performed (P < .05).
Wearing gloves or gloves plus gowns reduced the frequency of patient-to-patient transfer of a viral DNA surrogate marker. The use of gloves plus gowns during interactions with the source patient did not reduce transfer in comparison to gloves alone.
There is controversy regarding whether the addition of cover gowns offers a substantial benefit over gloves alone in reducing personnel contamination and preventing pathogen transmission.
Simulated patient care interactions.
To evaluate the efficacy of different types of barrier precautions and to identify routes of transmission.
In randomly ordered sequence, 30 personnel each performed 3 standardized examinations of mannequins contaminated with pathogen surrogate markers (cauliflower mosaic virus DNA, bacteriophage MS2, nontoxigenic Clostridioides difficile spores, and fluorescent tracer) while wearing no barriers, gloves, or gloves plus gowns followed by examination of a noncontaminated mannequin. We compared the frequency and routes of transfer of the surrogate markers to the second mannequin or the environment.
For a composite of all surrogate markers, transfer by hands occurred at significantly lower rates in the gloves-alone group (OR, 0.02; P < .001) and the gloves-plus-gown group (OR, 0.06; P = .002). Transfer by stethoscope diaphragms was common in all groups and was reduced by wiping the stethoscope between simulations (OR, 0.06; P < .001). Compared to the no-barriers group, wearing a cover gown and gloves resulted in reduced contamination of clothing (OR, 0.15; P < .001), but wearing gloves alone did not.
Wearing gloves alone or gloves plus gowns reduces hand transfer of pathogens but may not address transfer by devices such as stethoscopes. Cover gowns reduce the risk of contaminating the clothing of personnel.
Background: Patients with methicillin-resistant Staphylococcus aureus (MRSA) colonization often shed MRSA, resulting in contamination of surfaces in their room. It is not known whether MRSA-colonized patients also frequently contaminate surfaces during medical appointments and other activities outside their room. Methods: We conducted an observational cohort study of MRSA-colonized long-term care facility (LTCF) residents to determine the frequency and mechanisms of contamination of surfaces outside patient rooms. Nares, skin, and clothing of patients in contact precautions for MRSA were cultured for MRSA, and high-touch surfaces in the residents’ room were contaminated with the live virus bacteriophage MS2 and cauliflower mosaic virus DNA. The participants were observed during activities and medical appointments outside their rooms for 3 days, and sites that were contacted were sampled for recovery of MRSA, bacteriophage MS2, and cauliflower mosaic virus DNA. Results: As shown in Fig. 1, bacteriophage MS2 and cauliflower mosaic virus DNA was transferred to 1 or more surfaces outside the resident’s room by 5 of the 7 participants, and MRSA was recovered from surfaces touched by 6 (86%) participants. MRSA was recovered during 16 of 35 episodes (46%) where sampling was performed, and recovery was similar for medical appointments (eg, hemodialysis, physical therapy) and nonmedical activities (eg, using the dining room or activity center). Moreover, MRSA, MS2, and the viral DNA marker were recovered both from sites contacted only by participants’ hands and from sites contacted only by clothing. Bacteriophage MS2 and the viral DNA marker were also recovered from portable equipment and from the nursing station. Conclusions: MRSA-colonized LTCF residents frequently disseminated MRSA and viral surrogate markers to surfaces outside their rooms through contact with contaminated hands and clothing. Efforts to reduce contamination of hands and clothing might reduce the risk for pathogen transmission.
Background: Barrier precautions (eg, gloves and gowns) are often used in clinical settings to reduce the risk for transmission of healthcare-associated pathogens. However, uncertainty persists regarding the efficacy of different types of barrier precautions in preventing transmission. Methods: We used simulated patient care interactions to compare the effectiveness of different levels of barrier precautions in reducing transfer of pathogen surrogate markers. Overall, 30 personnel performed standardized examinations of contaminated mannequins while wearing either no barriers, gloves, or gloves plus cover gowns followed by examination of a noncontaminated mannequin; the order of the barrier precautions was randomly assigned. Participants used their usual technique for hand hygiene, stethoscope cleaning, and protective equipment removal. The surrogate markers included cauliflower mosaic virus DNA, bacteriophage MS2, nontoxigenic Clostridium difficile spores, and a fluorescent tracer. We compared the frequency and route of transfer of each of the surrogate markers to the second mannequin or to the surrounding environment. Results: As shown in Fig. 1, wearing gloves alone or gloves plus gowns significantly reduced transfer of each of the surrogate markers by the hands of participants (P < .05 for each marker). However, wearing gloves or gloves plus gowns only modestly reduced transfer by stethoscopes despite cleaning of stethoscopes between exams by approximately half of the participants. Contamination of the clothing of participants was significantly reduced in the glove plus gown group versus the gloves only or no-barriers groups (P < .05). Conclusion: Barrier precautions are effective in reducing hand transfer of pathogens from patient to patient, but transfer may still occur via devices such as stethoscopes. Cover gowns reduce the risk for contamination of the clothing of personnel.
Funding: Proprietary Organization: The Center for Disease Control.
The hands of healthcare personnel are the most important source for transmission of healthcare-associated pathogens. The role of contaminated fomites such as portable equipment, stethoscopes, and clothing of personnel in pathogen transmission is unclear.
To study routes of transmission of cauliflower mosaic virus DNA markers from 31 source patients and from environmental surfaces in their rooms.
A 3-month observational cohort study.
A Veterans’ Affairs hospital.
After providing care for source patients, healthcare personnel were observed during interactions with subsequent patients. Putative routes of transmission were identified based on recovery of DNA markers from sites of contact with the patient or environment. To assess plausibility of fomite-mediated transmission, we assessed the frequency of transfer of methicillin-resistant Staphylococcus aureus (MRSA) from the skin of 25 colonized patients via gloved hands versus fomites.
Of 145 interactions involving contact with patients and/or the environment, 41 (28.3%) resulted in transfer of 1 or both DNA markers to the patient and/or the environment. The DNA marker applied to patients’ skin and clothing was transferred most frequently by stethoscopes, hands, and portable equipment, whereas the marker applied to environmental surfaces was transferred only by hands and clothing. The percentages of MRSA transfer from the skin of colonized patients via gloved hands, stethoscope diaphragms, and clothing were 52%, 40%, and 48%, respectively.
Fomites such as stethoscopes, clothing, and portable equipment may be underappreciated sources of pathogen transmission. Simple interventions such as decontamination of fomites between patients could reduce the risk for transmission.
For patients with methicillin-resistant Staphylococcus aureus (MRSA) colonization, a traditional fist-bump greeting did not significantly reduce MRSA transfer in comparison to a handshake. However, transfer was reduced with a modified fist bump that minimized the surface area of contact and when hand hygiene was performed before the handshake.
In a tertiary-care hospital and affiliated long-term care facility, a stewardship intervention focused on patients with Clostridioides difficile infection (CDI) was associated with a significant reduction in unnecessary non-CDI antibiotic therapy. However, there was no significant reduction in total non-CDI therapy or in the frequency of CDI recurrence.
In a crossover trial, a gown designed to increase skin coverage at the hands and wrists significantly reduced contamination of personnel during personal protective equipment (PPE) removal, and education on donning and doffing technique further reduced contamination. Simple modifications of PPE and education can reduce contamination during PPE removal.
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.
A DNA marker inoculated onto portable equipment on a medical ward was disseminated to other wards when equipment was shared and to a physician work room and the hospital cafeteria by personnel. These results demonstrate the plausibility of pathogen transmission in healthcare facilities in the absence of shared ward exposure.