Education & Certifications
Ph.D., University of Illinois at Chicago, Environmental and Occupational Health Sciences (2019)
MS, University of Illinois at Chicago, Environmental and Occupational Health Sciences/Industrial Hygiene (2015)
Respiratory viruses in the patient environment.
Infection control and hospital epidemiology
To characterize the presence and magnitude of viruses in the air and on surfaces in the rooms of hospitalized patients with respiratory viral infections, and to explore the association between care activities and viral contamination.Prospective observational study.Acute-care academic hospital.In total, 52 adult patients with a positive respiratory viral infection test within 3 days of observation participated. Healthcare workers (HCWs) were recruited in staff meetings and at the time of patient care, and 23 wore personal air-sampling devices.Viruses were measured in the air at a fixed location and in the personal breathing zone of HCWs. Predetermined environmental surfaces were sampled using premoistened Copan swabs at the beginning and at the end of the 3-hour observation period. Preamplification and quantitative real-time PCR methods were used to quantify viral pathogens.Overall, 43% of stationary and 22% of personal air samples were positive for virus. Positive stationary air samples were associated with ≥5 HCW encounters during the observation period (odds ratio [OR], 5.3; 95% confidence interval [CI], 1.2-37.8). Viruses were frequently detected on all of the surfaces sampled. Virus concentrations on the IV pole hanger and telephone were positively correlated with the number of contacts made by HCWs on those surfaces. The distributions of influenza, rhinoviruses, and other viruses in the environment were similar.Healthcare workers are at risk of contracting respiratory virus infections when delivering routine care for patients infected with the viruses, and they are at risk of disseminating virus because they touch virus-contaminated fomites.
View details for DOI 10.1017/ice.2019.299
View details for PubMedID 32043434
Respiratory viruses on personal protective equipment and bodies of healthcare workers.
Infection control and hospital epidemiology
To characterize the magnitude of virus contamination on personal protective equipment (PPE), skin, and clothing of healthcare workers (HCWs) who cared for patients having acute viral infections.Prospective observational study.Acute-care academic hospital.A total of 59 HCWs agreed to have their PPE, clothing, and/or skin swabbed for virus measurement.The PPE worn by HCW participants, including glove, face mask, gown, and personal stethoscope, were swabbed with Copan swabs. After PPE doffing, bodies and clothing of HCWs were sampled with Copan swabs: hand, face, and scrubs. Preamplification and quantitative polymerase chain reaction (qPCR) methods were used to quantify viral RNA copies in the swab samples.Overall, 31% of glove samples, 21% of gown samples, and 12% of face mask samples were positive for virus. Among the body and clothing sites, 21% of bare hand samples, 11% of scrub samples, and 7% of face samples were positive for virus. Virus concentrations on PPE were not statistically significantly different than concentrations on skin and clothing under PPE. Virus concentrations on the personal stethoscopes and on the gowns were positively correlated with the number of torso contacts (P < .05). Virus concentrations on face masks were positively correlated with the number of face mask contacts and patient contacts (P < .05).Healthcare workers are routinely contaminated with respiratory viruses after patient care, indicating the need to ensure that HCWs complete hand hygiene and use other PPE to prevent dissemination of virus to other areas of the hospital. Modifying self-contact behaviors may decrease the presence of virus on HCWs.
View details for DOI 10.1017/ice.2019.298
View details for PubMedID 31668149
Environmental Contact and Self-contact Patterns of Healthcare Workers: Implications for Infection Prevention and Control.
Clinical infectious diseases : an official publication of the Infectious Diseases Society of America
2019; 69 (Supplement_3): S178–S184
Respiratory viruses on fomites can be transferred to sites susceptible to infection via contact by hands or other fomites.Care for hospitalized patients with viral respiratory infections was observed in the patient room for 3-hour periods at an acute care academic medical center for over a 2 year period. One trained observer recorded the healthcare activities performed, contacts with fomites, and self-contacts made by healthcare workers (HCWs), while another observer recorded fomite contacts of patients during the encounter using predefined checklists.The surface contacted by HCWs during the majority of visits was the patient (90%). Environmental surfaces contacted by HCWs frequently during healthcare activities included the tray table (48%), bed surface (41%), bed rail (41%), computer station (37%), and intravenous pole (32%). HCWs touched their own torso and mask in 32% and 29% of the visits, respectively. HCWs' self-contacts differed significantly among HCW job roles, with providers and respiratory therapists contacting themselves significantly more times than nurses and nurse technicians (P < .05). When HCWs performed only 1 care activity, there were significant differences in the number of patient contacts and self-contacts that HCWs made during performance of multiple care activities (P < .05).HCWs regularly contact environmental surfaces, patients, and themselves while providing care to patients with infectious diseases, varying among care activities and HCW job roles. These contacts may facilitate the transmission of infection to HCWs and susceptible patients.
View details for DOI 10.1093/cid/ciz558
View details for PubMedID 31517975
Environmental and Personal Protective Equipment Contamination during Simulated Healthcare Activities.
Annals of work exposures and health
Providing care to patients with an infectious disease can result in the exposure of healthcare workers (HCWs) to pathogen-containing bodily fluids. We performed a series of experiments to characterize the magnitude of environmental contamination-in air, on surfaces and on participants-associated with seven common healthcare activities. The seven activities studied were bathing, central venous access, intravenous access, intubation, physical examination, suctioning and vital signs assessment. HCWs with experience in one or more activities were recruited to participate and performed one to two activities in the laboratory using task trainers that contained or were contaminated with fluorescein-containing simulated bodily fluid. Fluorescein was quantitatively measured in the air and on seven environmental surfaces. Fluorescein was quantitatively and qualitatively measured on the personal protective equipment (PPE) worn by participants. A total of 39 participants performed 74 experiments, involving 10-12 experimental trials for each healthcare activity. Healthcare activities resulted in diverse patterns and levels of contamination in the environment and on PPE that are consistent with the nature of the activity. Glove and gown contamination were ubiquitous, affirming the value of wearing these pieces of PPE to protect HCW's clothing and skin. Though intubation and suctioning are considered aerosol-generating procedures, fluorescein was detected less frequently in air and at lower levels on face shields and facemasks than other activities, which suggests that the definition of aerosol-generating procedure may need to be revised. Face shields may protect the face and facemask from splashes and sprays of bodily fluids and should be used for more healthcare activities.
View details for DOI 10.1093/annweh/wxz048
View details for PubMedID 31165859
Potential for Occupational Exposures to Pathogens during Bronchoscopy Procedures.
Journal of occupational and environmental hygiene
Bronchoscopy is classified as an aerosol-generating procedure, but it is unclear what drives the elevated infection risk observed among healthcare personnel performing the procedure. The objective of this study was to characterize pathways through which bronchoscopists may be exposed to infectious agents during bronchoscopy procedures. Aerosol number concentrations (0.2-1 µm aerodynamic diameter) were measured using a P-Trak Ultrafine Particle Counter 8525 and mass concentrations (<10 µm) were measured using a SidePak Personal Aerosol Monitor AM510 near the head of patients during bronchoscopy procedures. Procedure pathway, number of patient coughs, number of suctioning events, number of contacts with different surfaces by the pulmonologist, and the use and doffing of personal protective equipment were recorded by the investigator on a specially designed form. Any pulmonologist performing a bronchoscopy procedure was eligible to participate. A total of 18 procedures were observed. Mean particle number and mass concentrations were not elevated during procedures relative to those measured before or after the procedure, on average, but the concentrations were highly variable, exhibiting high levels periodically. Patients frequently coughed during procedures (median 65 coughs, range: 0-565 coughs), and suctioning was commonly performed (median 6.5 suctioning events, range: 0-42). In all procedures, pulmonologists contacted the patient (mean 22.3 contacts, range: 1-48), bronchoscope (mean 19.4 contacts, range: 1-46), and at least one environmental surface (mean 31.2 contacts, range: 3-62). In the majority of procedures, the participant contacted his or her body or personal protective equipment (PPE), with a mean of 17.3 contacts (range: 4-48). More often than not, the observed PPE doffing practices differed from those recommended. Bronchoscopy procedures were associated with short-term increased ultrafine or respirable aerosol concentrations, and there were opportunities for contact transmission.
View details for DOI 10.1080/15459624.2019.1649414
View details for PubMedID 31407954
Personal protective equipment doffing practices of healthcare workers.
Journal of occupational and environmental hygiene
During the doffing of personal protective equipment (PPE), pathogens can be transferred from the PPE to the bodies of healthcare workers (HCWs), putting HCWs and patients at risk of exposure and infection. PPE doffing practices of HCWs who cared for patients with viral respiratory infections were observed at an acute care hospital from March 2017 to April 2018. A trained observer recorded doffing performance of HCWs inside the patient rooms using a pre-defined checklist based on the Centers for Disease Control and Prevention (CDC) guideline. Doffing practices were observed 162 times during care of 52 patients infected with respiratory viral pathogens. Out of the 52 patients, 30 were in droplet and contact isolation, 21 were in droplet isolation, and 1 was in contact isolation. Overall, 90% of observed doffing was incorrect, with respect to the doffing sequence, doffing technique, or use of appropriate PPE. Common errors were doffing gown from the front, removing face shield of the mask, and touching potentially contaminated surfaces and PPE during doffing. Deviations from the recommended PPE doffing protocol are common and can increase potential for contamination of the HCW's clothing or skin after providing care. There is a clear need to change the approach used to training HCWs in PPE doffing practices.
View details for DOI 10.1080/15459624.2019.1628350
View details for PubMedID 31291152
Environmental and body contamination from cleaning vomitus in a health care setting: A simulation study
AMERICAN JOURNAL OF INFECTION CONTROL
2018; 46 (4): 397–401
Environmental service workers may be exposed to pathogens during the cleaning of pathogen-containing bodily fluids.Participants with experience cleaning hospital environments were asked to clean simulated, fluorescein-containing vomitus using normal practices in a simulated patient room. Fluorescein was visualized in the environment and on participants under black lights. Fluorescein was quantitatively measured on the floor, in the air, and on gloves and shoe covers.In all 21 trials involving 7 participants, fluorescein was found on the floor after cleaning and on participants' gloves. Lower levels of floor contamination were associated with the use of towels to remove bulk fluid (ρ = -0.56, P = .01). Glove contamination was not associated with the number or frequency of contacts with environmental surfaces, suggesting contamination occurs with specific events, such as picking up contaminated towels. Fluorescein contamination on shoe covers was measured in 19 trials. Fluorescein was not observed on participants' facial personal protective equipment, if worn, or faces. Contamination on other body parts, primarily the legs, was observed in 8 trials. Fluorescein was infrequently quantified in the air.Using towels to remove bulk fluid prior to mopping is part of the recommended cleaning protocol and should be used to minimize residual contamination. Contamination on shoes and the floor may serve as reservoirs for pathogens.
View details for DOI 10.1016/j.ajic.2017.10.003
View details for Web of Science ID 000428371800010
View details for PubMedID 29174193
View details for PubMedCentralID PMC6200404
Contact patterns during cleaning of vomitus: A simulation study
AMERICAN JOURNAL OF INFECTION CONTROL
2017; 45 (12): 1312–17
Environmental service workers cleaning bodily fluids may transfer pathogens through the environment and to themselves through contacts.Participants with experience in cleaning of hospital environments were asked to clean simulated vomitus using normal practices in a simulated patient room while being videorecorded. Contacts with environmental surfaces and self were later observed.In 21 experimental trials with 7 participants, environmental surfaces were contacted 26.8 times per trial, at a frequency of 266 contacts per hour, on average. Self-contact occurred in 9 of 21 trials, and involved 1-18 contacts, mostly to the upper body. The recommended protocol of cleaning bodily fluids was followed by a minority of participants (2 of 7), and was associated with fewer surface contacts, improved cleaning quality, and different tool use. Participants used different cleaning practices, but each employed similar practices each time they performed an experimental trial.Training in the use of the recommended protocol may standardize cleaning practices and reduce the number of surface contacts.
View details for DOI 10.1016/j.ajic.2017.07.005
View details for Web of Science ID 000416571600008
View details for PubMedID 28844383
Chicago transit authority train noise exposure
JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE
2017; 14 (6): D86–D91
To characterize noise exposure of riders on Chicago Transit Authority (CTA) trains, we measured noise levels twice on each segment of 7 of the 8 CTA train lines, which are named after colors, yielding 48 time-series measurements. We found the Blue Line has the highest noise levels compared to other train lines, with mean 76.9 dBA; and that the maximum noise level, 88.9 dBA occurred in the tunnel between the Chicago and Grand stations. Train segments involving travel through a tunnel had significantly higher noise levels than segments with travel on elevated and ground level tracks. While 8-hr doses inside the passenger cars were not estimated to exceed occupational exposure limits, train operators ride in a separate cab with operational windows and may therefore have higher noise exposures than riders. Despite the low risk of hearing loss for riders on CTA trains, in part because transit noise accounts for a small part of total daily noise exposure, 1-min average noise levels exceeded 85 dBA at times. This confirms anecdotal observations of discomfort due to noise levels, and indicates a need for noise management, particularly in tunnels.
View details for DOI 10.1080/15459624.2017.1285490
View details for Web of Science ID 000402523200003
View details for PubMedID 28278069