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This SHEA white paper identifies knowledge gaps and challenges in healthcare epidemiology research related to COVID-19 with a focus on core principles of healthcare epidemiology. These gaps, revealed during the worst phases of the COVID-19 pandemic, are described in 10 sections: epidemiology, outbreak investigation, surveillance, isolation precaution practices, personal protective equipment (PPE), environmental contamination and disinfection, drug and supply shortages, antimicrobial stewardship, healthcare personnel (HCP) occupational safety, and return to work policies. Each section highlights three critical healthcare epidemiology research questions with detailed description provided in supplemental materials. This research agenda calls for translational studies from laboratory-based basic science research to well-designed, large-scale studies and health outcomes research. Research gaps and challenges related to nursing homes and social disparities are included. Collaborations across various disciplines, expertise and across diverse geographic locations will be critical.
To test the feasibility of targeted gown and glove use by healthcare personnel caring for high-risk nursing-home residents to prevent Staphylococcus aureus acquisition in short-stay residents.
Uncontrolled clinical trial.
This study was conducted in 2 community-based nursing homes in Maryland.
The study included 322 residents on mixed short- and long-stay units.
During a 2-month baseline period, all residents had nose and inguinal fold swabs taken to estimate S. aureus acquisition. The intervention was iteratively developed using a participatory human factors engineering approach. During a 2-month intervention period, healthcare personnel wore gowns and gloves for high-risk care activities while caring for residents with wounds or medical devices, and S. aureus acquisition was measured again. Whole-genome sequencing was used to assess whether the acquisition represented resident-to-resident transmission.
Among short-stay residents, the methicillin-resistant S. aureus acquisition rate decreased from 11.9% during the baseline period to 3.6% during the intervention period (odds ratio [OR], 0.28; 95% CI, 0.08–0.92; P = .026). The methicillin-susceptible S. aureus acquisition rate went from 9.1% during the baseline period to 4.0% during the intervention period (OR, 0.41; 95% CI, 0.12–1.42; P = .15). The S. aureus resident-to-resident transmission rate decreased from 5.9% during the baseline period to 0.8% during the intervention period.
Targeted gown and glove use by healthcare personnel for high-risk care activities while caring for residents with wounds or medical devices, regardless of their S. aureus colonization status, is feasible and potentially decreases S. aureus acquisition and transmission in short-stay community-based nursing-home residents.
To evaluate the effect of the burden of Staphylococcus aureus colonization of nursing home residents on the risk of S. aureus transmission to healthcare worker (HCW) gowns and gloves.
Multicenter prospective cohort study.
Setting and participants:
Residents and HCWs from 13 community-based nursing homes in Maryland and Michigan.
Residents were cultured for S. aureus at the anterior nares and perianal skin. The S. aureus burden was estimated by quantitative polymerase chain reaction detecting the nuc gene. HCWs wore gowns and gloves during usual care activities; gowns and gloves were swabbed and then cultured for the presence of S. aureus.
In total, 403 residents were enrolled; 169 were colonized with methicillin-resistant S. aureus (MRSA) or methicillin-sensitive S. aureus (MSSA) and comprised the study population; 232 were not colonized and thus were excluded from this analysis; and 2 were withdrawn prior to being swabbed. After multivariable analysis, perianal colonization with S. aureus conferred the greatest odds for transmission to HCW gowns and gloves, and the odds increased with increasing burden of colonization: adjusted odds ratio (aOR), 2.1 (95% CI, 1.3–3.5) for low-level colonization and aOR 5.2 (95% CI, 3.1–8.7) for high level colonization.
Among nursing home patients colonized with S. aureus, the risk of transmission to HCW gowns and gloves was greater from those colonized with greater quantities of S. aureus on the perianal skin. Our findings inform future infection control practices for both MRSA and MSSA in nursing homes.
To understand hospital policies and practices as the COVID-19 pandemic accelerated, the Society for Healthcare Epidemiology of America (SHEA) conducted a survey through the SHEA Research Network (SRN). The survey assessed policies and practices around the optimization of personal protection equipment (PPE), testing, healthcare personnel policies, visitors of COVID-19 patients in relation to procedures, and types of patients. Overall, 69 individual healthcare facilities responded in the United States and internationally, for a 73% response rate.
The role of demographic characteristics, such as sex and race, as risk factors for colonization with multidrug-resistant organisms, has not been established in the nursing home setting. We demonstrate significantly higher prevalence overall in male patients, and sex differences are dependent on organism of interest and body site.
To estimate the risk of transmission of antibiotic-resistant Gram-negative bacteria (RGNB) to gowns and gloves worn by healthcare personnel (HCP) when providing care to residents of community-based nursing facilities to identify the types of care and resident characteristics associated with transmission.
Prospective observational study.
Settings and participants
Residents and HCP from 13 community-based nursing facilities in Maryland and Michigan.
Perianal swabs were collected from residents and cultured to detect RGNB. HCP wore gowns and gloves during usual care activities, and at the end of each interaction, these were swabbed in a standardized manner. Transmission of RGNB from a colonized resident to gowns and gloves was estimated. Odds ratios (ORs) of transmission associated with type of care or resident characteristic were calculated.
We enrolled 403 residents and their HCP in this study. Overall, 19% of enrolled residents with a perianal swab (n=399) were colonized with at least 1 RGNB. RGNB transmission to either gloves or gowns occurred during 11% of the 584 interactions. Showering the resident, hygiene or toilet assistance, and wound dressing changes were associated with a high risk of transmission. Glucose monitoring and assistance with feeding or medication were associated with a low risk of transmission. Residents with a pressure ulcer were 3 times more likely to transmit RGNB than residents without one (OR, 3.3; 95% confidence interval [CI], 1.0–11.1).
Gown and glove use in community nursing facilities should be prioritized for certain residents and care interactions that are deemed a high risk for transmission.
The impact of healthcare system integration on infection prevention programs is unknown. Using catheter-associated urinary tract infection (CAUTI) prevention as an example, we hypothesize that US Department of Veterans Affairs (VA) nursing homes have a more robust infection prevention infrastructure due to integration and centralization compared with non–VA nursing homes.
VA and non-VA nursing homes participating in the AHRQ Safety Program for Long-Term Care collaborative.
Nursing homes provided baseline information about their infection prevention programs to assess strengths and gaps related to CAUTI prevention via a needs assessment questionnaire.
A total of 353 of 494 nursing homes from 41 states (71%; 47 VA and 306 non-VA facilities) responded. VA nursing homes reported more hours per week devoted to infection prevention-related activities (31 vs 12 hours; P<.001) and were more likely to have committees that reviewed healthcare-associated infections. Compared with non-VA facilities, a higher percentage of VA nursing homes reported tracking CAUTI rates (94% vs 66%; P<.001), sharing CAUTI data with leadership (94% vs 70%; P=.014) and with nursing personnel (85% vs 56%, P=.003). However, fewer VA nursing homes reported having policies for appropriate catheter use (64% vs 81%; P=.004) and catheter insertion (83% vs 94%; P=.004).
Among nursing homes participating in an AHRQ-funded collaborative, VA and non-VA nursing homes differed in their approach to CAUTI prevention. Best practices from both settings should be applied universally to create an optimal infection prevention program within emerging integrated healthcare systems.
To assess knowledge about infection prevention among nursing home personnel and identify gaps potentially addressable through a quality improvement collaborative.
Baseline knowledge assessment of catheter-associated urinary tract infection, asymptomatic bacteriuria, antimicrobial stewardship, and general infection prevention practices for healthcare-associated infections.
Nursing homes across 14 states participating in the national “Agency for Healthcare Research and Quality Safety Program for Long-Term Care: Healthcare-Associated Infections/Catheter-Associated Urinary Tract Infection.”
Each facility aimed to obtain responses from at least 10 employees (5 licensed and 5 unlicensed). We assessed the percentage of correct responses.
A total of 184 (78%) of 236 participating facilities provided 1 response or more. Of the 1,626 respondents, 822 (50.6%) were licensed; 117 facilities (63.6%) were for-profit. While 99.1% of licensed personnel recognized the definition of asymptomatic bacteriuria, only 36.1% knew that pyuria could not distinguish a urinary tract infection from asymptomatic bacteriuria. Among unlicensed personnel, 99.6% knew to notify a nurse if a resident developed fever or confusion, but only 27.7% knew that cloudy, smelly urine should not routinely be cultured. Although 100% of respondents reported receiving training in hand hygiene, less than 30% knew how long to rub hands (28.5% licensed, 25.2% unlicensed) or the most effective agent to use (11.7% licensed, 10.6% unlicensed).
This national assessment demonstrates an important need to enhance infection prevention knowledge among healthcare personnel working in nursing homes to improve resident safety and quality of care.
To estimate the frequency of methicillin-resistant Staphylococcus aureus (MRSA) transmission to gowns and gloves worn by healthcare workers (HCWs) interacting with nursing home residents to better inform infection prevention policies in this setting
Participants were recruited from 13 community-based nursing homes in Maryland and Michigan
Residents and HCWs from these nursing homes
Residents were cultured for MRSA at the anterior nares and perianal or perineal skin. HCWs wore gowns and gloves during usual care activities. At the end of each activity, a research coordinator swabbed the HCW’s gown and gloves.
A total of 403 residents were enrolled; 113 were MRSA colonized. Glove contamination was higher than gown contamination (24% vs 14% of 954 interactions; P<.01). Transmission varied greatly by type of care from 0% to 24% for gowns and from 8% to 37% for gloves. We identified high-risk care activities: dressing, transferring, providing hygiene, changing linens, and toileting the resident (OR >1.0; P<.05). We also identified low-risk care activities: giving medications and performing glucose monitoring (OR<1.0; P<.05). Residents with chronic skin breakdown had significantly higher rates of gown and glove contamination.
MRSA transmission from MRSA-positive residents to HCW gown and gloves is substantial; high-contact activities of daily living confer the highest risk. These activities do not involve overt contact with body fluids, skin breakdown, or mucous membranes, which suggests the need to modify current standards of care involving the use of gowns and gloves in the nursing home setting.
Infect. Control Hosp. Epidemiol. 2015;36(9):1050–1057
Forage sorghum is an important component of the fodder supply chain in the arid and semi-arid regions of the world because of its high productivity, ability to utilize water efficiently and adaptability to a wide range of climatic conditions. Identification of high-yielding stable genotypes (G) across environments (E) is challenging because of the complex G × E interactions (GEI). In the present study, the performance of 16 forage sorghum genotypes over seven locations across the rainy seasons of 2010 and 2011 was investigated using GGE biplot analysis. Analysis of variance revealed the existence of significant GEI for fodder yield and all eight associated phenotypic traits. Location accounted for a higher proportion of the variation (0·72–0·91), while genotype contributed only 0·06–0·21 of total variation in different traits. Genotype-by-location interactions contributed 0·02–0·13 of total variation. Promising genotypes for fodder yield and each of the associated traits could be identified effectively using a graphical biplot approach. The majority of test locations were highly correlated. A ‘Which-won-where’ study partitioned the test locations into two mega-environments (MEs): ME1 was represented by five locations with COFS 29 as the best genotype, while ME2 had two locations with S 541 as the best genotype. The existence of two MEs suggested a need for location-specific breeding. Genotype-by-trait biplots indicated that improvement for forage yield could be achieved through indirect selection for plant height, leaf number and early vigour.
Incidental findings arising from imaging research have important implications for patient safety. Magnetic resonance imaging is widespread in multiple sclerosis (MS) studies and care, yet the prevalence rate of incidental findings in MS is poorly defined. The absence of such reports in the MS literature suggests that such findings may be deemed inappropriate for documentation in research publications, or possibly, not fully reported at all.
We sought to document incidental findings from a study designed to detect features of chronic cerebrospinal venous insufficiency (CCSVI) in MS patients and control subjects.
Magnetic resonance images were obtained as part of a prospective study conducted between October 2010 and September 2012. Patients with MS (relapsing-remitting, primary progressive, secondary progressive), clinically isolated syndromes, and neuromyelitis optica and age/sex-matched healthy controls were included. All images were reviewed by neuro-radiologists for quality-control purposes.
Magnetic resonance imaging was successfully obtained in 166 participants (110 patients, 56 controls). Incidental abnormalities (n = 33) were detected in 15% of patients (n = 17) and 27% of controls (n = 15), comprising 19% overall (n = 32).
The prevalence of incidental findings from the MS population was not significantly different from the control population. However, the overall prevalence was high and warrants a careful management strategy for future imaging studies.
We investigated an outbreak of 396 Salmonella enterica serotype I 4,5,12:i:- infections to determine the source. After 7 weeks of extensive hypothesis-generation interviews, no refined hypothesis was formed. Nevertheless, a case-control study was initiated. Subsequently, an iterative hypothesis-generation approach used by a single interviewing team identified brand A not-ready-to-eat frozen pot pies as a likely vehicle. The case-control study, modified to assess this new hypothesis, along with product testing indicated that the turkey variety of pot pies was responsible. Review of product labels identified inconsistent language regarding preparation, and the cooking instructions included undefined microwave wattage categories. Surveys found that most patients did not follow the product's cooking instructions and did not know their oven's wattage. The manufacturer voluntarily recalled pot pies and improved the product's cooking instructions. This investigation highlights the value of careful hypothesis-generation and the risks posed by frozen not-ready-to-eat microwavable foods.
We describe the internal cerebral vein (ICV) sign, which is a hypo-opacification of the ICV on computed tomogram angiography (CTA) as a new marker of increased cerebral blood transit-time in ipsilateral internal carotid artery occlusions (ICAO).
A retrospective analysis of 153 patients with acute unilateral M1 middle cerebral artery (MCA) occlusions ± ICAOs was performed. The degree of contrast opacification of the ICV on the ipsilesional side was compared to that of the unaffected side.
Of 153 patients in our study, 135 had M1 MCA occlusions ± intra-cranial ICAO (M1±iICAO) and 18 had isolated extracranial ICAO (eICAO). In the patients with proximal M1±iICAO, 57/65 (87.1%) showed the ICV sign. Of the 8 patients without the ICV sign in this group, 6 had prominent lenticulostriate arteries arising from the non-occluded M1 segment, 1 had a recurrent artery of Huebner, and 1 had filling of distal ICA/M1 segment through prominent Circle of Willis collaterals. For the 70 patients with isolated distal M1±iICAO, 7/70 (10%) showed the ICV sign, with all 7 showing occluded lenticulostriate arteries. Of the patients with eICAO, 8/18 showed the ICV sign, all 8 with the ICV sign had poor Circle of Willis collaterals.
The ICV sign correlates well with presence of proximal M1±iICAO in patients with either occluded lenticulostriate arteries or poor Circle of Willis collaterals. In patients with eICAO, the sign correlates with reduced Circle of Willis collaterals and may be a marker of increased ipsilateral cerebral blood transit time.
Infection surveillance definitions for long-term care facilities (ie, the McGeer Criteria) have not been updated since 1991. An expert consensus panel modified these definitions on the basis of a structured review of the literature. Significant changes were made to the criteria defining urinary tract and respiratory tract infections. New definitions were added for norovirus gastroenteritis and Clostridum difficile infections.
The emergence of epidemic cholera in post-earthquake Haiti portended a public health disaster of uncertain magnitude. In order to coordinate relief efforts in an environment with limited healthcare infrastructure and stretched resources, timely and realistic projections of the extent of the cholera outbreak were crucial. Projections were shared with Government and partner organizations beginning 5 days after the first reported case and were updated using progressively more advanced methods as more surveillance data became available. The first projection estimated that 105 000 cholera cases would occur in the first year. Subsequent projections using different methods estimated up to 652 000 cases and 163 000–247 000 hospitalizations during the first year. Current surveillance data show these projections to have provided reasonable approximations of the observed epidemic. Providing the real-time projections allowed Haitian ministries and external aid organizations to better plan and implement response measures during the evolving epidemic.
We report the degradation of low temperature photoluminescence (PL) from Si/SiGe three-dimensional cluster morphology nanostructures under continuous photoexcitation. The PL intensity initially decreases slowly for about 15 minutes, and then decreases rapidly, until only ∼ 10% of the original PL intensity remains. A complete recovery of the PL requires restoring the sample temperature to ∼ 300K. We propose that a slow accumulation of charge in SiGe clusters enhances the rate of Auger recombination and results in the observed PL degradation.
In August 2008, a large outbreak of Shiga toxin-producing Escherichia coli (STEC) O111:NM infections associated with a buffet-style restaurant in rural Oklahoma was identified. A case-control study of restaurant patrons and a retrospective cohort study of catered event attendees were conducted coupled with an environmental investigation to determine the outbreak's source and mode of transmission. Of 1823 persons interviewed, 341 (18·7%) met the outbreak case definition; 70 (20·5%) were hospitalized, 25 (7·3%) developed haemolytic uraemic syndrome, and one died. Multiple food items were significantly associated with illness by both bivariate and multivariate analyses, but none stood out as a predominant transmission vehicle. All water, food, and restaurant surface swabs, and stool cultures from nine ill employees were negative for the presence of Shiga toxin and E. coli O111:NM although epidemiological evidence suggested the outbreak resulted from cross-contamination of restaurant food from food preparation equipment or surfaces, or from an unidentified infected food handler.