Shedding of methicillin-resistant Staphylococcus aureus by colonized patients during procedures and patient care activities

Empowering patients to prevent healthcare-associated infections

In recent years there has been increasing interest in the empowerment of patients to serve as partners in efforts to prevent healthcare-associated infections. However, patients often have limited awareness of the risk for acquisition and dissemination of healthcare-associated pathogens and have received limited information on how they might participate in infection prevention efforts. This review highlights some of the areas where patient empowerment initiatives in infection control and antimicrobial stewardship may be useful and reviews available evidence that such initiatives can be beneficial. Although patients are the primary focus of these initiatives, inclusion of family members should be considered in many situations because they often play a major role in healthcare decision-making.

Staphylococcus aureus in Horses in Nigeria: Occurrence, Antimicrobial, Methicillin and Heavy Metal Resistance and Virulence Potentials

Staphylococcus aureus was isolated from a total of 360 nasal and groin skin swabs from 180 systematic randomly-selected horses slaughtered for meat at Obollo-Afor, Enugu State, Southeast Nigeria and antimicrobial, methicillin and heavy metal resistance profile and virulence potentials of the isolates established. Baird-Parker agar with egg yolk tellurite was used for S. aureus isolation. S. aureus isolates were confirmed biochemically and serologically using a specific S. aureus Staphytect Plus™ latex agglutination test kit. The antimicrobial resistance profile, methicillin, vancomycin and inducible clindamycin resistance, and β-lactamase production of the isolates were determined with disc diffusion. Tolerance to Copper, Cadmium, Lead and Zinc was assessed using the agar dilution method and virulence potentials were determined using phenotypic methods. Forty-three (23.9%) of the 180 horses harbored S. aureus. Some 71 S. aureus were recovered from the 360 samples. Two (2.8%) of the 71 S. aureus were methicillin-resistant S. aureus (MRSA) and 69 (97.2%) were methicillin-susceptible. MRSA was recovered from 2 (1.1%) of the 180 horses. Some 9.4% of the isolates were multiple drug-resistant (MDR). The mean multiple antibiotic resistance indices (MARI) for the isolates was 0.24. Heavy metal resistance rate of the isolates ranged between 35.4-70.4%. The isolates, including the MRSA strains, displayed virulence potentials as clumping factor and catalase, gelatinase, caseinase, heamolysin, and biofilm was at the rate of 100%, 53.5%, 43.7%, 18.3% and 23.9%, respectively. This study showed that a considerable percentage of horses slaughtered in Obollo-Afor Southeastern Nigeria are potential reservoirs of virulent multiple drug- and heavy metal-resistant S. aureus, including MRSA, that could spread to humans and the environment.

Understanding short-term transmission dynamics of methicillin-resistant Staphylococcus aureus in the patient room

OBJECTIVE

Little is known about the short-term dynamics of methicillin-resistant Staphylococcus aureus (MRSA) transmission between patients and their immediate environment. We conducted a real-life microbiological evaluation of environmental MRSA contamination in hospital rooms in relation to recent patient activity.

DESIGN

Observational pilot study.

SETTING

Two hospitals, hospital 1 in Zurich, Switzerland, and hospital 2 in Ann Arbor, Michigan, United States.

PATIENTS

Inpatients with MRSA colonization or infection.

METHODS

At baseline, the groin, axilla, nares, dominant hands of 10 patients and 6 environmental high-touch surfaces in their rooms were sampled. Cultures were then taken of the patient hand and high-touch surfaces 3 more times at 90-minute intervals. After each swabbing, patients' hands and surfaces were disinfected. Patient activity was assessed by interviews at hospital 1 and analysis of video footage at hospital 2. A contamination pressure score was created by multiplying the number of colonized body sites with the activity level of the patient.

RESULTS

In total, 10 patients colonized and/or infected with MRSA were enrolled; 40 hand samples and 240 environmental samples were collected. At baseline, 30% of hands and 20% of high-touch surfaces yielded MRSA. At follow-up intervals, 8 (27%) of 30 patient hands, and 10 (6%) of 180 of environmental sites were positive. Activity of the patient explained 7 of 10 environmental contaminations. Patients with higher contamination pressure score showed a trend toward higher environmental contamination.

CONCLUSION

Environmental MRSA contamination in patient rooms was highly dynamic and was likely driven by the patient's MRSA body colonization pattern and the patient activity.

Capturing portable medical equipment disinfection data via an automated novel disinfection tracking system

BACKGROUND

Portable Medical Equipment (PME) such as workstations-on-wheels (WOWs) and vital signs machines (VMs) have been linked to healthcare-associated infections. Routine visual monitoring of PME disinfection is difficult. An automated Disinfection Tracking System (DTS) was used to record and report the number of disinfection events of PME in a hospital setting.

METHODS

The study was conducted in 2 acute-care units for 25-days to determine the pattern of recorded events from DTS on PME. Devices record disinfection events as moisture events and automatically store on a central database. DTS devices with "screen-on" feedback and "screen-off" devices with no display were placed on 10 WOWs and 5 VMs on separate units.

RESULTS

A total of 421 moisture events were recorded for the "screen-on" and 345 for the "screen-off", during the 25-day implementation period on the 2 different hospital units. The highest number of events occurred between 6:00am-7:00am, with 69 & 75 moisture events recorded for Units 1 and 2, respectively.

CONCLUSIONS

The pattern of disinfection events for WOWs and VMs demonstrated that most events occurred regularly at the times corresponding with nursing shift change. The DTS has the potential to continuously record, and report data related to PME disinfection.

Shedding of methicillin-resistant Staphylococcus aureus and multidrug-resistant gram-negative bacilli during outpatient appointments and procedures outside hospital rooms

BACKGROUND

Limited information is available on the frequency of and risk factors for shedding of health care-associated pathogens in settings outside patient rooms.

METHODS

We conducted a cohort study of hospitalized or recently discharged patients with methicillin-resistant Staphylococcus aureus (MRSA) (N = 39) or multidrug-resistant gram-negative bacilli (MDR-GNB) (N = 11) colonization to determine the frequency of environmental shedding during appointments outside hospital rooms or during outpatient clinic visits. Chi-square tests were performed to identify patient-level factors associated with environmental shedding. Spa typing was performed for environmental and nasal MRSA isolates.

RESULTS

Of 50 patients enrolled, 39 were colonized with MRSA and 11 with MDR-GNB. Shedding during 1 or more appointments occurred more often for patients colonized with MRSA versus MDR-GNB (15 of 39, 38.5% versus 0 of 11, 0%; P = .02). The presence of a wound with a positive culture for MRSA was associated with shedding of MRSA during appointments (11 of 15, 73.3% with shedding versus 4 of 24, 16.7% with no shedding; P = .008). Eighty percent of environmental MRSA isolates were genetically related to concurrent nasal isolates based on spa typing.

CONCLUSIONS

Environmental shedding of MRSA occurs frequently during appointments outside hospital rooms or during outpatient clinic visits. Decontamination of surfaces and strategies that reduce shedding of MRSA could reduce the risk for transmission in these settings.

Microbial bioburden of inpatient and outpatient areas beyond patient hospital rooms

OBJECTIVE

To investigate the frequency of environmental contamination in hospital areas outside patient rooms and in outpatient healthcare facilities.

DESIGN

Culture survey.

SETTING

This study was conducted across 4 hospitals, 4 outpatient clinics, and 1 surgery center.

METHODS

We conducted 3 point-prevalence culture surveys for methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, Clostridioides difficile, Candida spp, and gram-negative bacilli including Enterobacteriaceae, Pseudomonas aeruginosa, Acinetobacter baumanii, and Stenotrophomonas maltophilia in each facility. In hospitals, high-touch surfaces were sampled from radiology, physical therapy, and mobile equipment and in emergency departments, waiting rooms, clinics, and endoscopy facilities. In outpatient facilities, surfaces were sampled in exam rooms including patient and provider areas, patient bathrooms, and waiting rooms and from portable equipment. Fluorescent markers were placed on high-touch surfaces and removal was assessed 1 day later.

RESULTS

In the hospitals, 110 (9.4%) of 1,195 sites were positive for 1 or more bacterial pathogens (range, 5.3%-13.7% for the 4 hospitals) and 70 (5.9%) were positive for Candida spp (range, 3.7%-5.9%). In outpatient facilities, 31 of 485 (6.4%) sites were positive for 1 or more bacterial pathogens (range, 2% to 14.4% for the 5 outpatient facilities) and 50 (10.3%) were positive for Candida spp (range, 3.9%-23.3%). Fluorescent markers had been removed from 33% of sites in hospitals (range, 28.4%-39.7%) and 46.3% of sites in outpatient clinics (range, 7.4%-82.8%).

CONCLUSIONS

Surfaces in hospitals outside patient rooms and in outpatient facilities are frequently contaminated with healthcare-associated pathogens. Improvements in cleaning and disinfection practices are needed to reduce contamination.

Evaluation of a continuously active disinfectant for decontamination of portable medical equipment

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.

Timing and route of contamination of hospitalized patient rooms with healthcare-associated pathogens

OBJECTIVE

To investigate the timing and routes of contamination of the rooms of patients newly admitted to the hospital.

DESIGN

Observational cohort study and simulations of pathogen transfer.

SETTING

A Veterans' Affairs hospital.

PARTICIPANTS

Patients newly admitted to the hospital with no known carriage of healthcare-associated pathogens.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Shedding of multidrug-resistant gram-negative bacilli by colonized patients during procedures and patient care activities

BACKGROUND

Medical procedures and patient care activities may facilitate environmental shedding of health care-associated pathogens.

METHODS

We conducted a cohort study of hospitalized patients in contact precautions for carriage of extended-spectrum beta-lactamase (ESBL)-producing gram-negative bacilli (N = 38) or carbapenem-resistant gram-negative bacilli (CR-GNB) (N = 22) to determine the frequency of environmental shedding during procedures and care activities. Perirectal, wound, and skin were cultured for ESBL-producing and CR-GNB. High-touch surfaces and portable equipment were disinfected before and cultured after procedures; control cultures were collected in the absence of procedures.

RESULTS

Of 60 patients enrolled, 34 (57%) had positive perirectal and/or skin or wound cultures. For these 34 patients, 15 (44%) shed their colonizing organism to surfaces during 1 or more procedures. Patients with shedding had significantly higher concentrations of the pathogens recovered from perirectal swabs than those with no shedding (mean, 3.5 vs 2.2 log₁₀ colony-forming units per swab; P < .01). Environmental shedding occurred more frequently during procedures and care activities than in the absence of a procedure (21 of 117, 18% vs 1 of 61, 2%; P < .01), and 6 of 56 (10%) portable devices used for procedures became contaminated.

CONCLUSIONS

Environmental shedding of antibiotic-resistant gram-negative bacilli occurs frequently during medical procedures and patient care activities. Decontamination of surfaces and equipment and approaches that reduce the burden of carriage could reduce the risk for dissemination.

Use of viral DNA surrogate markers to study routes of transmission of healthcare-associated pathogens

BACKGROUND

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.

OBJECTIVE

To study routes of transmission of cauliflower mosaic virus DNA markers from 31 source patients and from environmental surfaces in their rooms.

DESIGN

A 3-month observational cohort study.

SETTING

A Veterans' Affairs hospital.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Environmental Contamination with Candida Species in Multiple Hospitals Including a Tertiary Care Hospital with a Candida auris Outbreak

Background

Environmental sources have been implicated as a potential source for exogenous acquisition of Candida species, particularly the emerging multidrug-resistant Candida auris. However, limited information is available on environmental reservoirs of Candida species in healthcare facilities.

Methods

During a 6-month period, cultures for Candida species were collected from high-touch surfaces in patient rooms and from portable equipment in 6 US acute care hospitals in 4 states. Additional cultures were collected from sink drains and floors in one of the hospitals and from high-touch surfaces, portable equipment, and sink drains in a hospital experiencing an outbreak due to C. auris. Candida species were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectometry.

Results

Candida species were recovered from patient rooms in 4 of the 6 hospitals. Seven of 147 patient room cultures (4.8%) and 1 of 57 (1.8%) portable equipment cultures were positive, with the most common species being C. parapsilosis. For the hospital where additional sites were sampled, Candida species were recovered from 8 of 22 (36.4%) hospital room floors and 4 of 17 (23.5%) sink drains. In the facility with a C. auris outbreak, Candida species were frequently recovered from sink drains (20.7%) and high-touch surfaces (15.4%), but recovery of C. auris was uncommon (3.8% of high-touch surfaces, 3.4% of sink drains, and 0% of portable equipment) and only present in rooms that currently or recently housed a patient with C. auris.

Conclusion

Candida species often contaminate surfaces in hospitals and may be particularly common on floors and in sink drains. However, C. auris contamination was uncommon in a facility experiencing an outbreak, suggesting that current cleaning and disinfection practices can be effective in minimizing environmental contamination.

Improving the Use of Personal Protective Equipment: Applying Lessons Learned

Unrecognized transmission of pathogens in healthcare settings can lead to colonization and infection of both patients and healthcare personnel. The use of personal protective equipment (PPE) is an important strategy to protect healthcare personnel from contamination and to prevent the spread of pathogens to subsequent patients. However, optimal PPE use is difficult, and healthcare personnel may alter delivery of care because of the PPE. Here, we summarize recent research from the Prevention Epicenters Program on healthcare personnel contamination and improvement of the routine use of PPE as well as Ebola-specific PPE. Future efforts to optimize the use of PPE should include increasing adherence to protocols for PPE use, improving PPE design, and further research into the risks, benefits, and best practices of PPE use.

Beyond high-touch surfaces: Portable equipment and floors as potential sources of transmission of health care-associated pathogens

Efforts to improve environmental cleaning and disinfection typically focus primarily on high-touch surfaces in patient rooms. This review highlights evidence that portable equipment and other shared devices and floors may be underappreciated as sources of dissemination of health care-associated pathogens. Practical approaches to address these sites of contamination are emphasized.