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

2020 ◽  
pp. 1-6
Author(s):  
Manish Thakur ◽  
Heba Alhmidi ◽  
Jennifer L. Cadnum ◽  
Annette L. Jencson ◽  
Jessica Bingham ◽  
...  
Keyword(s):  
Dna Markers ◽  
Veterans Affairs ◽  
Pathogen Transmission ◽  
Cauliflower Mosaic Virus ◽  
Healthcare Personnel ◽  
Portable Equipment ◽  
Environmental Surfaces ◽  
Observational Cohort ◽  
Healthcare Associated

Abstract 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.

scholarly journals 1142. Use of DNA Markers to Assess the Potential for Pathogen Transmission from Physicians’ White Coats

2018 ◽  
Vol 5 (suppl_1) ◽  
pp. S343-S343
Author(s):  
Daniel Van Aartsen ◽  
Manish Thakur ◽  
Khalid M Dousa ◽  
Anubhav Kanwar ◽  
Jennifer Cadnum ◽  
...  
Keyword(s):  
Dna Markers ◽  
Dna Marker ◽  
Pathogen Transmission ◽  
Cauliflower Mosaic Virus ◽  
Clinical Settings ◽  
Dress Code ◽  
Indirect Contact ◽  
Environmental Surfaces ◽  
Polymerase Chain ◽  
Healthcare Associated

Abstract Background Physicians’ white coats are often contaminated, but seldom cleaned. A “bare below the elbows” dress code policy has been advocated as a strategy to reduce the risk for transmission of healthcare-associated pathogens by white coats. However, transfer of contamination by clothing has not been demonstrated in clinical settings and it is not known if long sleeves are the major source of transfer. Methods We observed physicians during routine patient encounters and characterized the frequency of direct and indirect contact between white coats and the patient or environmental surfaces. To assess transfer from white coats in clinical settings, we applied one cauliflower mosaic virus DNA marker to the sleeve cuffs and another to the coat pockets of physicians prior to routine patient encounters. Polymerase chain reaction was used to determine whether DNA markers from the clothing sites were transferred to patients or environmental surfaces. Results Ninety percent of observed patient encounters included one or more direct or indirect contacts between a physician’s white coat and a patient or the environment. Direct contact occurred on average 1.7 times per encounter and indirect contact (i.e., physicians’ hands contacting the coat prior to touching the patient or environment) occurred on average 2.3 times per encounter. The figure shows the frequency and distribution of sites of direct and indirect contact with white coats. Of 11 patient encounters with DNA-contaminated white coats, five (45%) resulted in transfer of one or both DNA markers; there were three transfers from sleeve cuffs and three from coat pockets. Conclusion Contaminated white coats may be an under-appreciated source for transmission of healthcare-associated pathogens. Our results provide support for the bare below the elbows policy, but also highlight the potential for indirect transfer of pathogens from other sites on white coats. Disclosures All authors: No reported disclosures.

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

2021 ◽  
pp. 1-6
Author(s):  
Sarah N. Redmond ◽  
Basya S. Pearlmutter ◽  
Yilen K. Ng-Wong ◽  
Heba Alhmidi ◽  
Jennifer L. Cadnum ◽  
...  
Keyword(s):  
Pathogen Detection ◽  
Veterans Affairs ◽  
Portable Equipment ◽  
Healthcare Facilities ◽  
Clostridioides Difficile ◽  
Bacteriophage Ms2 ◽  
Vancomycin Resistant Enterococci ◽  
Observational Cohort ◽  
Vancomycin Resistant ◽  
Healthcare Associated

Abstract 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.

scholarly journals Multidrug-resistant Organisms in Hospitals: What Is on Patient Hands and in Their Rooms?

2019 ◽  
Vol 69 (11) ◽  
pp. 1837-1844 ◽  
Author(s):  
Lona Mody ◽  
Laraine L Washer ◽  
Keith S Kaye ◽  
Kristen Gibson ◽  
Sanjay Saint ◽  
...  
Keyword(s):  
Multidrug Resistant ◽  
Healthcare Personnel ◽  
Resistant Organism ◽  
Dominant Hand ◽  
Paired Samples ◽  
Environmental Surfaces ◽  
Healthcare Associated ◽  
The Impact ◽  
Panton Valentine Leukocidin

AbstractBackgroundThe impact of healthcare personnel hand contamination in multidrug-resistant organism (MDRO) transmission is important and well studied; however, the role of patient hand contamination needs to be characterized further.MethodsPatients from 2 hospitals in southeast Michigan were recruited within 24 hours of arrival to their room and followed prospectively using microbial surveillance of nares, dominant hand, and 6 high-touch environmental surfaces. Sampling was performed on admission, days 3 and 7, and weekly until discharge. Paired samples of methicillin-resistant Staphylococcus aureus (MRSA) isolated from the patients’ hand and room surfaces were evaluated for relatedness using pulsed-field gel electrophoresis and staphylococcal cassette chromosome mec, and Panton-Valentine leukocidin typing.ResultsA total of 399 patients (mean age, 60.8 years; 49% male) were enrolled and followed for 710 visits. Fourteen percent (n = 56/399) of patients were colonized with an MDRO at baseline; 10% (40/399) had an MDRO on their hands. Twenty-nine percent of rooms harbored an MDRO. Six percent (14/225 patients with at least 2 visits) newly acquired an MDRO on their hands during their stay. New MDRO acquisition in patients occurred at a rate of 24.6/1000 patient-days, and in rooms at a rate of 58.6/1000 patient-days. Typing demonstrated a high correlation between MRSA on patient hands and room surfaces.ConclusionsOur data suggest that patient hand contamination with MDROs is common and correlates with contamination on high-touch room surfaces. Patient hand hygiene protocols should be considered to reduce transmission of pathogens and healthcare-associated infections.

Sharing is not always a good thing: Use of a DNA marker to investigate the potential for ward-to-ward dissemination of healthcare-associated pathogens

2018 ◽  
Vol 40 (2) ◽  
pp. 214-216 ◽  
Author(s):  
Heba Alhmidi ◽  
Jennifer L. Cadnum ◽  
Annette L. Jencson ◽  
Ali Abdulfatah Gweder ◽  
Curtis J. Donskey
Keyword(s):  
Dna Marker ◽  
Pathogen Transmission ◽  
Medical Ward ◽  
Good Thing ◽  
Portable Equipment ◽  
Healthcare Facilities ◽  
Healthcare Associated ◽  
Physician Work

AbstractA 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.

Use of simulations to evaluate the effectiveness of barrier precautions to prevent patient-to-patient transfer of healthcare-associated pathogens

2020 ◽  
pp. 1-6
Author(s):  
Heba Alhmidi ◽  
Daniel F. Li ◽  
Jennifer L. Cadnum ◽  
Muhammed F. Haq ◽  
Natalia C. Pinto-Herrera ◽  
...  
Keyword(s):  
Mosaic Virus ◽  
Pathogen Transmission ◽  
Cauliflower Mosaic Virus ◽  
Surrogate Markers ◽  
Fluorescent Tracer ◽  
Clostridioides Difficile ◽  
Bacteriophage Ms2 ◽  
Different Types ◽  
Healthcare Associated ◽  
Standardized Examinations

Abstract Background: 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. Design: Simulated patient care interactions. Objective: To evaluate the efficacy of different types of barrier precautions and to identify routes of transmission. Methods: 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. Results: 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. Conclusions: 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.

Effectiveness of barrier precautions for prevention of patient-to-patient transfer of a viral DNA surrogate marker

2020 ◽  
pp. 1-6
Author(s):  
Heba Alhmidi ◽  
Jennifer L. Cadnum ◽  
Yilen K. Ng-Wong ◽  
Annette L. Jencson ◽  
Brigid M. Wilson ◽  
...  
Keyword(s):  
Dna Markers ◽  
Odds Ratio ◽  
Dna Marker ◽  
Surrogate Marker ◽  
Pathogen Transmission ◽  
Cauliflower Mosaic Virus ◽  
Patient Transfer ◽  
Viral Dna ◽  
Patient Interactions ◽  
Subsequent Patient

Abstract Background: Gloves and gowns are used during patient care to reduce contamination of personnel and prevent pathogen transmission. Objective: 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. Methods: 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. Results: 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). Conclusions: 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.

scholarly journals Bare Below the Elbows: A Randomized Trial to Determine Whether Wearing Short-Sleeved Coats Reduces the Risk for Pathogen Transmission

2017 ◽  
Vol 4 (suppl_1) ◽  
pp. S34-S34
Author(s):  
Amrita John ◽  
Heba Alhmidi ◽  
Melany Gonzalez-Orta ◽  
Jennifer Cadnum ◽  
Curtis J Donskey
Keyword(s):  
Patient Care ◽  
Randomized Trial ◽  
Mosaic Virus ◽  
Dna Marker ◽  
Pathogen Transmission ◽  
Cauliflower Mosaic Virus ◽  
Healthcare Personnel ◽  
Dress Code ◽  
Viral Dna ◽  
The Uk

Abstract Background Physician’s white coats are frequently contaminated, but seldom cleaned. Therefore, in the UK, a “bare below the elbows” dress code policy includes a recommendation that personnel wear short sleeves. However, it has not been demonstrated that wearing short sleeves reduces the likelihood of pathogen transmission. Methods We conducted a randomized, cross-over trial involving simulated patient care interactions to test the hypothesis that transmission of pathogens occurs less frequently when personnel wear short- vs long-sleeved coats. Healthcare personnel were randomized to wear either long- or short-sleeved white coats while examining a mannequin contaminated with cauliflower mosaic virus DNA followed by examination of an uncontaminated mannequin. We compared the frequency of transfer of the DNA marker with the sleeves and/or wrists and with the uncontaminated mannequin. During work rounds, physicians were observed to determine how often the sleeves of white coats contacted patients or the environment. Results During work rounds and simulated examinations, the sleeve cuff of long-sleeved coats frequently contacted the patient/mannequin or environment. Contamination with the DNA marker was detected significantly more often on the sleeves and/or wrists when personnel wore long- vs short-sleeved coats (5 of 20, 25% vs 0 of 20, 0%; P = 0.02). In one of five (20%) instances of sleeve and/or wrist contamination, the DNA marker was transferred to the second mannequin. It was also observed that healthcare personnel were less likely to include their wrist in handwashing between simulations if they were wearing long-sleeved coats. Conclusion During simulations of patient care, the sleeve cuff of long-sleeved white coats frequently became contaminated with a viral DNA marker that could be transferred. These results provide support for the recommendation that healthcare personnel wear short sleeves to reduce the risk for pathogen transmission. Disclosures All authors: No reported disclosures.

Hand Hygiene Practices After Brief Encounters With Patients: An Important Opportunity for Prevention

2007 ◽  
Vol 28 (3) ◽  
pp. 341-345 ◽  
Author(s):  
Rebecca E. Dedrick ◽  
Ronda L. Sinkowitz-Cochran ◽  
Candace Cunningham ◽  
Robert R. Muder ◽  
Peter Perreiah ◽  
...  
Keyword(s):  
Hand Hygiene ◽  
Median Duration ◽  
Healthcare Workers ◽  
Veterans Affairs ◽  
Patient Contact ◽  
Contact Precautions ◽  
Hygiene Practices ◽  
Direct Patient Contact ◽  
Environmental Surfaces ◽  
Healthcare Associated

Objective.To identify characteristics of encounters between healthcare workers (HCWs) and patients that correlated with hand hygiene adherence among HCWs.Design.Observational study.Setting.Intensive care unit in a Veterans Affairs hospital.Participants.HCWs.Results.There were 767 patient encounters observed (48.6% involved nurses, 20.6% involved physicians, and 30.8% involved other HCWs); 39.8% of encounters involved patients placed under contact precautions. HCW contact with either the patient or surfaces in the patient's environment occurred during all encounters; direct patient contact occurred during 439 encounters (57.4%), and contact with environmental surfaces occurred during 710 encounters (92.6%). The median duration of encounters was 2 minutes (range, <1 to 51 minutes); 33.6% of encounters lasted 1 minute or less, with no significant occupation-associated differences in the median duration of encounters. Adherence with hand hygiene practices was correlated with the duration of the encounter, with overall adherences of 30.0% after encounters of ≤1 minute, 43.4% after encounters of >1 to ≤2 minutes, 51.1% after encounters of >3 to ≤5 minutes, and 64.9% after encounters of >5 minutes (P < .001 by the x2 for trend). In multivariate analyses, longer encounter duration, contact precautions status, patient contact, and nursing occupation were independently associated with adherence to hand hygiene recommendations.Conclusions.In this study, adherence to hand hygiene practices was lowest after brief patient encounters (ie, <2 minutes). Brief encounters accounted for a substantial proportion of all observed encounters, and opportunities for hand contamination occurred during all brief encounters. Therefore, improving adherence after brief encounters may have an important overall impact on the transmission of healthcare-associated pathogens and may deserve special emphasis in the design of programs to promote adherence to hand hygiene practices.

scholarly journals Use of Simulations to Evaluate the Effectiveness of Barrier Precautions for Prevention of pathogen Transmission

2020 ◽  
Vol 41 (S1) ◽  
pp. s82-s83
Author(s):  
Heba Alhmidi ◽  
Daniel Li ◽  
Jennifer Cadnum ◽  
Natalia Pinto Herrera ◽  
Muhammed Fawwaz Haq ◽  
...  
Keyword(s):  
Group Versus ◽  
Pathogen Transmission ◽  
Cauliflower Mosaic Virus ◽  
Clinical Settings ◽  
Surrogate Markers ◽  
Bacteriophage Ms2 ◽  
Different Types ◽  
Healthcare Associated ◽  
Standardized Examinations ◽  
Different Levels

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.Disclosures: None

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