Background: Contact precautions (CP) to prevent transmission of multidrug-resistant gram-negative (MDRGN) Enterobacteriaceae are recommended, although studies of discontinuation of CP (DcCP) have found no change in healthcare associated infections (HAI) due to extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae. Limited data exists on DcCP for MDRGN in a large health system. Methods: We performed a retrospective observational study analyzing the relationship between use of CP and HAI due to two definitions of MDRGN Enterobacteriaceae: ESBL, and non-susceptibility to ≥3 drug classes (3DC-GNR), with carbapenem resistant Enterobacteriaceae (CRE) serving as control. The study included all inpatient admissions from 2/2017 through 9/2022 at 21 acute care hospitals. Hospitals had latitude to determine CP practices based on local risk assessment, but in 2/2018, system-wide transmission-based precautions guidance was updated to recommend DcCP for MDRGN Enterobacteriaceae and in 12/2019 was updated to clarify DcCP specifically for ESBL and 3DC-GNR while continuing CP for carbapenem-resistant organism carriage. We interviewed infection preventionists to define when CP were used for CRE, ESBL, and 3DC-GNR Enterobacteriaceae. HAI were defined using National Healthcare Safety Network criteria including all HAI categories. We compared the incidence rate of HAI attributable to the two MDRGN types in hospital months with and without use of CP, with HAI due to CRE as a comparison group since all hospitals used CP for CRE throughout the study period. Results: The periods of CP use, by hospital, are shown in Figure 1. Throughout the study period, there were 987 HAI attributed to ESBL Enterobacteriaceae, 579 due to 3DC-GNR Enterobacteriaceae, and 329 due to CRE. Figure 2 shows the unadjusted aggregate rate of HAI for each of the three MRGN types, including among hospitals with and without CP in each month, for ESBL and 3DC-GNR. In months with and without CP, the rate of HAI was 1.482/10,000 and 1.093/10,000 patient days (incidence rate ratio [IRR], 1.356 [95% confidence interval, 1.195-1.540]) for ESBL Enterobacteriaceae. In months with and without CP, the rate of HAI was 1.071/10,000 and 0.493/10,000 patient days (IRR,2.173[95% confidence interval, 1.838-2.569]) for 3DC-GNR Enterobacteriaceae. Conclusion: DcCP was not associated with an increase in HAI due to ESBL and 3DC-GNR Enterobacteriaceae in aggregated facilities that self-selected for DcCP. Facilities that used CP were associated with significantly higher rates of ESBL and 3DC-GNR Enterobacteriaceae, a relationship that did not change as hospitals DcCP for these MDRGN. Further analyses are necessary to assess for a causal relationship.

Background: Clinically non-indicated asymptomatic bacteriuria (ASB) identification precipitates higher reported catheter-associated urinary tract infection (CAUTI) rates and urinary tract infection (UTI)-directed antimicrobial overuse. Published diagnostic stewardship interventions to reduce ASB were mostly tested individually and heterogeneously; hence the optimal bundle approach is yet to be defined. Methods: We performed a single-center sequential quasi-experimental study involving hospitalized, emergency, and long-term care patients at a VA healthcare facility, retrospectively comparing standard of care (period 1: 1/1/2022-6/30/2022) to adding dedicated provider education on facility-approved urine-culturing indications (period 2: 7/1/2022-1/19/2023), then adding an electronic clinical decision support (CDS) tool (Figure 1) mandating urine-culturing indications selections (period 3: 1/20/2023-6/30/2023), then prospectively adding real-time case-based physician-generated audit/feedback emails on ordering appropriateness (period 4: 7/1/2023-12/31/2023). We randomly sampled approximately 500 orders from each period and measured the impact on the rate of urine reflex/culture orders, the percentage of non-indicated orders and ASB, UTI-directed antimicrobial usage, and facility-wide CAUTI rates. Results: We analyzed 2140 urine reflex/culture orders (Table 1 and Figure 2). The mean monthly orders per 1000 bed-days and percentage of non-indicated orders decreased with each intervention to one-fourth of the initial values by period 4 (p=0.0002). The ASB rate among positive cultures was unchanged from periods 1 to 2 but started to decrease in period 3 with the biggest impact in period 4 (p=0.01). Non-indicated and ASB-directed antimicrobial courses both followed the previous pattern, dropping from 28% and 26% baseline to 6% and 4% by the study conclusion (p=0.015 and 0.008), respectively. Estimated UTI-directed antimicrobials decreased by 34% (363/551) with antimicrobial-days saved from 4093 to 2846 per 6-month period. CAUTI rate relatively declined with each intervention, along with a reduction in ASB-attributed CAUTI’s from 45% (5/11) initially to 20% (1/5) in period 4. Conclusion: A stepwise urine-culturing diagnostic stewardship approach of clinical education, electronic CDS tool, plus real-time audit/feedback decreased overall urine reflex/cultures, non-indicated ordering, ASB identification, unnecessary antimicrobials, and CAUTI rates, with the greatest impact after bundling all interventions including order appropriateness audit/feedback.

Background: Nontuberculous mycobacteria (NTM) are ubiquitous potential pathogens implicated in healthcare-associated outbreaks. There is a paucity of studies describing transmission risk in the healthcare setting. To estimate the potential healthcare-associated transmission of NTM, we characterized the frequency of NTM clinical isolates across our multi-facility healthcare system. Method: We performed a retrospective review of all clinical NTM isolates at 21 healthcare facilities in a large health system between January 2019 through June 2023 (inclusion criteria: all first unique species). We analyzed the quarterly frequency of isolates for each species, by facility. We identified higher-than-expected species frequencies, which was defined as a quarterly frequency ≥50% higher than the average quarterly frequency for that facility, for the entire study period (analysis omitted for any hospital with an average quarterly frequency 10 unique patient isolates in any 12-month period or >2 in a single month except for M. abscessus at Hospital A. The quarterly frequency of the three most common species among hospitals with ≥2 unique isolates per 12-month period are displayed in figure 2. An increase of 50% from the average quarterly infection count occurred 34 times for M. avium complex across 10 hospitals, 14 times for M. gordonae across 2 hospitals and 14 times for M. lentiflavum across 2 hospitals (Figure 3). Conclusion: A diverse group of NTM were isolated across our healthcare system over the study period, most commonly M. avium complex, M. gordonae, and M. lentiflavum, each with hospital-specific temporal frequencies that suggest the potential for undetected outbreaks, while frequencies of less commonly isolated species were rarely suggestive of potential undetected outbreaks. Further epidemiologic investigation of in-hospital transmission routes, with whole genome sequencing to determine genetic relatedness, is necessary to identify undetected outbreaks.

Background: Inappropriate Clostridioides difficile (C. difficile) laboratory testing is common in hospitals and leads to over diagnosis, unnecessary treatment, and elevated hospital onset C. difficile infection (HO-CDI) metrics. Diagnostic stewardship is essential to avoid inappropriate testing, but limited data exists on optional interventions. Methods: A diagnostic stewardship intervention targeting CDI testing comprised of education and prospective audit with feedback was performed a VA facility (inpatient, outpatient, and long-term care units). Education on appropriate indications for CDI testing was provided in pre-intervention (9/2022 to 5/2023) and intervention periods (6/2023 to 12/2023). During the intervention period, all CDI tests (positive or negative) were audited after completion in real-time by an Infectious Diseases physician and feedback was given to ordering providers and/or their supervising physician (if trainee) for all tests not meeting an appropriate indication. Appropriate indication was defined as ≥3 liquid stools in 24 hours or symptoms of fulminant disease. Testing was considered inappropriate if no clinical symptoms, patient received laxatives within 48 hours, test was performed for test-of-cure or within 7 days of a prior test with no clinical change, or delayed testing in patients with diarrhea on admission. The rate of HO-CDI per 10,000 bed days of care (BDOC) per LabID event was compared during the pre-intervention and intervention periods, and ordering appropriateness was compared for all tests and hospital onset tests before (3/2023-5/2023) and after (6/2023-12/2023) feedback was performed. Results: After starting audit and feedback, HO-CDI rate decreased from 3.92 per 10,000 BDOC to 0.99 per 10,000 BDOC (p=0.03). HO-CDI rate among tests that were inappropriate was 2.19 and 0.80 per 10,000 BDOC during the pre-intervention and intervention periods, respectively (p=0.40). Average overall tests per month decreased from 37.8 to 28.1 after the intervention. Rate of all inappropriate tests decreased from 16.25 to 7.96 per 10,000 BDOC (p=0.04) and rate of hospital onset inappropriate tests trended toward decrease from 9.29 to 4.77 tests per 10,000 BDOC (p=0.07). The most common reasons for inappropriate testing were < 3 episodes of diarrhea in 24 hours (54% pre-intervention, 65% intervention) and laxative use (57% pre-intervention, 45% intervention). No cases of delayed testing leading to worsened disease were identified during the intervention. Cost savings for decreased tests were estimated at $150-300 per month. Conclusion: An intervention comprised of education and real-time audit and feedback of all CDI tests obtained at a VA facility resulted in decreased inappropriate testing and reduced the rate of HO-CDI.

“All or none” approaches to the use of contact precautions for methicillin-resistant Staphylococcus aureus (MRSA) both fail to recognize that transmission risk varies. This qualitative study assessed healthcare personnel perspectives regarding the feasibility of a risk-tailored approach to use contact precautions for MRSA more strategically in the acute care setting.

Au cours du vieillissement, les adultes ayant une déficience intellectuelle (DI) vivent de nombreux changements susceptibles d’influencer leurs possibilités d’exercer leurs activités quotidiennes et leurs rôles sociaux. Une bonne connaissance de leurs points de vue sur le sujet apparaît cruciale pour mieux adapter l’offre de services à leurs besoins. Cette recherche a pour but de mieux comprendre les points de vue des personnes ayant une DI à l’égard de leurs possibilités de participation sociale à travers l’avancée en âge. Des entrevues individuelles et un atelier participatif ont été réalisés avec des adultes âgés de 40 à 75 ans dans la ville de Québec. L’analyse de leurs propos a permis d’identifier leurs points de vue relatifs à trois thèmes, soit leurs capacités, les possibilités d’exercer leur participation sociale et les soutiens reçus. Pour conclure, des recommandations sont proposées afin que les pratiques soutiennent réellement leur participation sociale à travers l’avancée en âge.

Background: Current guidelines recommend contact precautions to prevent transmission of methicillin-resistant Staphylococcus aureus (MRSA) in acute-care hospitals. Prior literature demonstrates that discontinuation of contact precautions for MRSA has not been associated with an increase in carriage rates including surveillance-defined healthcare-associated infection (HAI) while horizontal infection prevention strategies are implemented. Objective: To analyze the impact of discontinuation of contact precautions on the rate of MRSA infections, including surveillance-defined HAI and transmission events identified through whole-genome sequencing (WGS) surveillance. Methods: In this single tertiary-care center, retrospective, observational, quality improvement analysis, we measured 2 MRSA HAI outcomes before and after discontinuation of contact precautions (ie, gown and gloves no longer required for care of patients with prior or current MRSA infections or colonization, effective December 2, 2020). First, we conducted a time-series analysis using linear regression modelling of NHSN reported MRSA HAI rates (January 2019–November 2022). We also calculated the frequency of WGS-confirmed MRSA transmission events before in the discontinuation of contact precautions (January 2019–August 2019) and after the discontinuation of contact precautions (January 2022–November 2022) periods. Surveillance HAI events were determined using NHSN definitions; MRSA transmission events were defined as an isolate identified ≥3 days after hospitalization or within 30 days of a healthcare exposure, genetically related by ≤15 single-nucleotide polymorphisms compared to ≥1 previously sequenced MRSA isolate. Results: We identified 171 MRSA HAIs in the 23 months before discontinuation of contact precautions, corresponding to 4.24 HAI per 10,000 patient days, and 129 HAIs in the 24 months after discontinuation of contact precautions, corresponding to 3.01 HAI per 10,000 patient days (Fig.). We detected a nonsignificant change in the trend in HAI rate before and after discontinuation of contact precautions (P = .22) as well as a significant immediate decrease in the MRSA HAI rate (P < 0 .001) at the time of discontinuation of contact precautions. In the WGS analysis 8 months before discontinuation of contact precautions, 11 MRSA transmission events were confirmed, comprising 4 clusters (0.75 per 10,000 patient days). In the WGS for the 11-month analysis period after discontinuation of contact precautions, there were 23 confirmed MRSA transmission events comprising 10 clusters (1.22 per 10,000 patient days; incidence rate ratio, 1.61; 95% CI, 0.75–3.66; P = .19). Conclusions: After discontinuation of contact precautions, there was no significant increase in MRSA HAI or transmission events. Further evaluation of the individual WGS transmission clusters will be helpful to determine whether discontinuation of contact precautions led to MRSA transmission in this facility in the period after discontinuation of contact precautions.

Disclosure: None

Training programs for infectious diseases fellows pursuing a career in infection prevention and control and hospital epidemiology are grounded in mentorship and organizational experience. In this commentary, we propose a competency-based framework for creating structured learning for infectious diseases fellows pursuing hospital epidemiology and related fields.

Tick-borne pathogens pose a significant risk to livestock, wildlife and public health. Host-seeking behaviours may depend on a combination of infection status and environmental factors. Here, we assessed the effects of habitat type and pathogen infection on host-seeking behaviour (questing) in the lone star tick, Amblyomma americanum. Ticks were collected using a tick drag from two different habitat types: xeric hammock and successional hardwood forests. Using a standardized assay, we recorded the likelihood of questing for each tick, the average height quested and total time spent questing and then tested each tick for the presence of Rickettsia spp. and Ehrlichia spp. using conventional polymerase chain reaction. We did not detect Ehrlichia in any ticks, although 30% tested positive for Rickettsia amblyommatis, a member of the Rickettsia spotted fever group. Ticks infected with R. amblyommatis spent less time questing compared to uninfected ticks, with infected ticks spending 85 s on average questing and uninfected ticks spending 112 s. Additionally, ticks collected from xeric hammock habitats spent over twice as long questing compared to ticks from successional hardwood forests. Ticks from xeric hammock spent 151 s on average questing while ticks from successional hardwood forest spent only 58 s during a 10-min observation period. These results demonstrate that habitat type and infection status can influence tick host-seeking behaviours, which can play a pivotal role in disease dynamics.

Antarctica's ice shelves modulate the grounded ice flow, and weakening of ice shelves due to climate forcing will decrease their ‘buttressing’ effect, causing a response in the grounded ice. While the processes governing ice-shelf weakening are complex, uncertainties in the response of the grounded ice sheet are also difficult to assess. The Antarctic BUttressing Model Intercomparison Project (ABUMIP) compares ice-sheet model responses to decrease in buttressing by investigating the ‘end-member’ scenario of total and sustained loss of ice shelves. Although unrealistic, this scenario enables gauging the sensitivity of an ensemble of 15 ice-sheet models to a total loss of buttressing, hence exhibiting the full potential of marine ice-sheet instability. All models predict that this scenario leads to multi-metre (1–12 m) sea-level rise over 500 years from present day. West Antarctic ice sheet collapse alone leads to a 1.91–5.08 m sea-level rise due to the marine ice-sheet instability. Mass loss rates are a strong function of the sliding/friction law, with plastic laws cause a further destabilization of the Aurora and Wilkes Subglacial Basins, East Antarctica. Improvements to marine ice-sheet models have greatly reduced variability between modelled ice-sheet responses to extreme ice-shelf loss, e.g. compared to the SeaRISE assessments.

From 2000 to 2009, rates of multidrug-resistant Acinetobacter baumanii increased 10-fold to 0.2 per 1,000 patient days. From 2010 to 2015, however, rates markedly declined and have stayed below 0.05 per 1,000 patient days. Herein, we present a 15-year trend analysis and discuss interventions that may have led to the decline.

Infect Control Hosp Epidemiol 2018;39:608–611