Understand current prevention practices used for Candidozyma auris and identify target areas for improvement.

Electronic survey.

Long-term acute care hospitals (LTACHs).

National Association of Long-Term Hospitals (NALTH) network facilities located in the United States.

REDCap survey distributed by email to 56 facilities in the NALTH network exploring knowledge and perceptions related to C. auris screening methods, prevention practices, barriers to prevention, and tools needed to improve containment.

Among 33 responses from 56 LTACHs, 23 (70%) had ever identified at least one case of C. auris infection or colonization. Eighteen (54%) reported identifying cases of C. auris within the past three months and nine (27%) had experienced suspected within-facility transmission. All facilities employed multimodal approaches for C. auris infection prevention. The most frequently reported barriers to effective C. auris prevention included lack of communication between healthcare facilities, inadequate training and education for frontline staff, and lack of compliance with personal protective equipment. The most impactful interventions anticipated to support future C. auris containment included improved communication between facilities at the time of patient transfer and standardized protocols for C. auris decolonization and surveillance.

Most LTACHs within the NALTH network reported firsthand experience with C. auris. Universally, facilities employed multimodal evidence-based infection prevention and control strategies targeted against C. auris. Future strategies anticipated to improve containment included improving interfacility communication of C. auris colonization status, development of effective decolonization protocols, and standardization of surveillance practices.

To reduce frequency of endotracheal aspirate culture (EAC) collection and decrease antibiotic days of therapy (DOT) for ventilator-associated tracheitis (VAT).

Quality improvement intervention.

Tertiary-care pediatric intensive care unit (PICU).

Admitted to the PICU with an endotracheal tube (ETT) or tracheostomy.

A clinical decision-support tool was implemented to provide clinical criteria for culture collection and microbiologic criteria for diagnosis, and to reduce treatment duration to 3 days. Key stakeholders were engaged, a nurse champion was identified, and a protocol was implemented. Culture rates (overall and serially repeated) and antibiotic DOT for VAT, each per 100 ETT/tracheostomy days, were analyzed. The proportion of VAT episodes treated for 3 days was also evaluated. Balancing measures included PICU mortality, ventilator-associated events, ventilator days, and length of stay. Statistical process control methods were used to analyze the data.

Across 1072 EACs sent and 213 VAT cases diagnosed, interventions led to a 23% reduction in monthly cultures (9.2 to 7.1 per 100 ETT/tracheostomy days) and a 53% reduction in serial culture use (1.5 to 0.7 per 100 ETT/tracheostomy days). There was a 53% reduction in monthly antibiotic DOT for VAT (10.8 to 5.1 per 100 ETT/tracheostomy days) and a 13-fold increase in the proportion of 3-day antibiotic prescriptions (5 to 65%). There was no increase in mortality, ventilator-associated events, ventilator days, or length of stay.

Standardized VAT guidelines in critically ill children can safely and effectively decrease culture and antibiotic use.

Assess knowledge, attitudes, and practices for control of Candidozyma auris among healthcare providers in long-term acute care hospitals (LTACHs).

Mixed methods; quantitative survey, followed by qualitative focus groups.

Two LTACHs with endemic spread of C. auris in the Chicago, Illinois region.

Convenience sample of frontline healthcare providers.

Fifty-three quantitative surveys were completed, and 21 individuals participated in qualitative focus groups. Survey participants were 92% female, 43% nurses, and 60% had >10 years of experience in their current role. They reported awareness of high-priority healthcare-associated multidrug-resistant pathogens, including C. auris (86%). Most participants agreed that C. auris is a national problem (74%), but only 56% agreed it was a problem in their own hospital. Barriers to C. auris prevention identified in the survey included understaffing (63%), lack of training (52%), lack of coworker accountability (48%), and lack of adequate time for task completion (49% for self, 48% for coworkers). Focus groups included 10 nurses, 5 patient care technicians, 3 secretaries, and 3 therapists. Focus groups highlighted the importance of enforcement and monitoring of prevention measures and the need for additional education. When asked how to improve infection prevention at their hospital, participants identified themes of education, improvements in enforcement and monitoring of prevention measures, staff support, and improvements in visual communication and healthcare design.

In this cohort of frontline LTACH healthcare providers, we identified multiple barriers to C. auris containment and elicited potential solutions. These insights suggest targets for future interventions to improve C. auris control.

Nursing home residents have been disproportionately impacted by respiratory virus-related morbidity and mortality due to inherent vulnerability and communal living environments. This study aims to identify nursing homes with higher infection rates during a period of intense SARS-CoV-2 transmission and explore facility-level characteristics potentially associated with infection surges.

A longitudinal k-means clustering approach followed by exploratory regression analyses.

U.S. Nursing homes reporting to the Centers for Disease Control and Prevention’s National Healthcare Safety Network (NHSN).

A longitudinal k-means method (kmlShape) classified the facilities based on their weekly SARS-CoV-2 incidence rate epidemic curve, identifying two categories (low vs high infection peak) based on the magnitude of infection peaks. A logistic regression model with bootstrapping was developed to assess facility characteristics associated with higher SARS-CoV-2 infection surges.

Among 11,990 nursing homes analyzed, 9,058 were classified as having a low infection peak, while 2,932 had a high infection peak. Nursing homes that are for-profit (OR = 1.570, 95% bootstrap confidence interval [BCI] 1.441–1.807), with high staff turnover (OR = 1.292, 95% BCI 1.154–1.451), or located in areas with higher social vulnerability (OR = 1.457, 95% BCI 1.239–1.880) were more likely to experience high infection peaks. Nursing homes with higher residents’ vaccination coverage (OR = .321, 95% BCI .248–.380) and located in urban areas were less likely to experience high infection peaks.

The facility-level characteristics associated with lower SARS-CoV-2 infection peaks may indicate resiliency and help evaluate the capacity of nursing homes to endure stressors such as respiratory viruses and other communicable illnesses.

To assess whether wind-driven natural ventilation in the Infectious Diseases Treatment Module (IDTM) can achieve ventilation performance consistent with airborne precaution requirements [160 liters per second (L/s)] and to estimate associated pathogen-specific infection risks.

An experimental campaign of air velocity measurements and CO2 decays were conducted to validate the developed computational fluid dynamics (CFD) model. The validated CFD model simulated wind-driven natural ventilation (1–4 m/s) for an L-shaped IDTM configuration under four structural scenarios defined by the presence or absence of patient porches and mosquito nets. Airborne infection risk was estimated using a Wells–Riley quanta-based model for seven representative airborne pathogens under short-duration healthcare worker exposure and prolonged patient co-exposure.

Ventilation performance varied widely based on wind speed and structural configuration. Airflow ranged from 7 L/s in the most restricted configuration (porch and mosquito nets present at 1 m/s) to over 3,100 L/s when mosquito nets were removed at 4 m/s.

When mapped to infection-risk estimates, ventilation rates at 160 L/s substantially reduced short-duration healthcare worker infection risk for all pathogens (≤1%), whereas prolonged co-exposure remained associated with high risk for high-emission pathogens despite high ventilation.

Under favorable wind conditions and optimized configurations, the IDTM can achieve ventilation rates consistent with the 160 L/s recommendation for airborne precautions. While this provides substantial protection for healthcare workers, individual-room isolation remains essential for patient management. Operationally, removing window-mounted nets is the most effective way to ensure safety targets are met; hybrid ventilation measures should be considered during low-wind conditions.

Multidrug-resistant organisms (MDROs) such as carbapenem-resistant Enterobacterales (CRE) are a significant public health threat. Patients colonized with MDROs are at higher risk of severe outcomes and can serve as a source of spread to others. The public health impact of a hypothetical agent that reduces MDRO load (i.e., pathogen reduction), including in the gastrointestinal tract, has not been described.

Compartmental models of CRE transmission in healthcare facilities were used to estimate the impact of a hypothetical pathogen reduction agent on CRE bloodstream infections (BSIs) and deaths.

The agent was assumed to reduce the time to pathogen clearance with effectiveness varying from 25–100% across simulations. Interventions were modeled in acute care hospitals (ACHs), critical access hospitals, long-term acute care hospitals (LTACHs), skilled nursing facilities, and ventilator-capable skilled nursing facilities (vSNFs). Direct effects (among patients who received the agent) and indirect effects (among patients who did not receive the agent) were estimated at the national healthcare network level.

At baseline without intervention, an estimated 2,086 CRE BSIs and 622 associated deaths occurred annually nationwide. Use of a pathogen reduction agent in LTACHs and vSNFs averted 69–75% of CRE BSIs nationally, with greater reductions when expanded to all facility types. Approximately 90% of averted CRE BSIs would have occurred in patients who were not administered the agent.

An effective pathogen reduction agent might substantially reduce MDRO infections and deaths among patients in U.S. healthcare facilities. New and expanded efforts are needed to accelerate the development of such products.

To assess the surveillance characteristics of respiratory syndromic surveillance criteria and their usefulness for monitoring infection trends in long-term care (LTC) facilities.

Retrospective observational study.

Two wards caring for children and adults with severe motor and intellectual disabilities in an LTC facility with 110 beds.

Inpatients who underwent respiratory pathogen testing during febrile episodes between November 2022 and December 2025 were included. Episodes were defined as testing events associated with febrile periods and surveillance characteristics were assessed among tested episodes.

Surveillance criteria, derived from the patient-based component of the CARES strategy, were defined as fever ≥38.0°C lasting for ≥2 consecutive days accompanied by at least one respiratory symptom. Associations between surveillance-positive episodes and microbiologically confirmed respiratory infections were examined, and temporal trends were assessed. Sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratios were calculated as descriptive surveillance characteristics.

Overall, 1,467 episodes from 124 patients were analyzed, including 375 microbiologically confirmed episodes. Surveillance criteria identified 140 (9.5%) episodes, of which 87 (62.1%) were microbiologically confirmed, with 23.2% sensitivity (95% confidence interval, 19.0–27.8) and 95.1% specificity (95% confidence interval, 93.7–96.3). Surveillance-positive episodes demonstrated temporal patterns consistent with confirmed infections.

Respiratory syndromic surveillance criteria demonstrated high specificity and captured temporal changes in microbiologically confirmed respiratory infections in LTC wards. Although not designed to identify every infection, simple signals, such as ≥2 surveillance-positive episodes per week, may facilitate monitoring respiratory infection activity and support timely infection prevention and control responses.

Early identification of patients colonized with multidrug-resistant organisms (MDROs) facilitates infection control interventions. We assessed a Public Health Risk Model’s ability to predict carbapenem-resistant Enterobacterales and other MDROs.

We retrospectively analyzed a medical intensive care unit patient cohort screened at time of admission for MDRO carriage (1/2017–1/2018). Encounters were linked to Illinois Hospital Discharge Data and assigned a public health risk model probability score. We compared the model’s performance to traditional screening strategies that use variables locally available to clinicians at time of admission (i.e., transfer from other hospital, tracheostomy, gastrostomy, pressure ulcer). Model discrimination was evaluated by quantifying the area under the curve (AUC). For each approach, we assessed sensitivity, specificity, and number needed to screen (NNS) to detect one MDRO carrier.

Model probability calculation was successful in 1237/1250 (98.9%) admissions. The model identified carbapenem-resistant Enterobacterales colonization well (AUC 0.82) and generalized to predict colonization with other healthcare-associated MDROs, including carbapenem-resistant Pseudomonas aeruginosa (AUC 0.82) and vancomycin-resistant enterococci (AUC 0.76). The model did not predict MDROs with known local community reservoirs, i.e., third-generation cephalosporin-resistant Enterobacterales (AUC 0.61) and methicillin-resistant Staphylococcus aureus (AUC 0.59). At the same NNS, the model had higher sensitivity compared to use of traditional screening strategies (68% versus 41%).

A risk model using patient-level healthcare exposure data from a state public health dataset identified critically ill patients likely to harbor healthcare-associated MDROs at the time of admission.

Understand current Candidozyma auris prevention practices in the United States and identify opportunities to improve containment.

Electronic survey.

Acute care hospitals.

Society for Healthcare Epidemiology (SHEA) Research Network (SRN) facilities located in the United States.

REDCap survey distributed via email exploring knowledge and perceptions related to C. auris screening methods, prevention practices, barriers to prevention, and tools needed to improve containment.

Responses were received from 51/96 (53%) U.S.-based SRN facilities, with 80% identifying as teaching hospitals. Two-thirds of facilities (34/51) reported first-hand experience with C. auris, with 15/34 also experiencing at least one C. auris outbreak. Routine C. auris screening occurred in 47% (24/51) of facilities. C. auris prevention practices commonly included patient isolation, signage to notify staff of isolation status, and placement in a single patient room. When asked to identify barriers to control of C. auris at their facility, participants ranked lack of communication between healthcare facilities, lack of infection control at outside healthcare facilities, and lack of training as the top three barriers. C. auris prevention resources or tools perceived to be most helpful in their facility included effective decolonization regimens, standardized protocols for C. auris screening, and improved communication between healthcare facilities.

SRN facilities commonly used isolation practices to prevent the spread of C. auris. Development of additional tools to improve prevention practices should target effective decolonization strategies and standardized screening protocols to support C. auris containment.

Heating, ventilation, and air conditioning (HVAC) systems can modulate the risk of respiratory virus transmission. In congregate living settings (CLS), variability in the quality of this infrastructure presents an improvement opportunity.

We performed a cross-sectional study of the air handling units (AHU) of HVAC systems across a network of CLS to identify the most common problems and specific opportunities to improve ventilation. A third-party expert performed systematic HVAC assessments, which were analyzed based on presence and function of key AHU components to determine their association with air changes per hour (ACH) using a multivariable linear regression model.

Across 15 participating CLS, the median ACH was 3.3 (IQR = 10.4) in common areas, 3.5 (IQR = 12.6) in resident rooms, and 6.6 (IQR = 9.7) in resident bathrooms. Closed outside air dampers and fans turned off was associated with decreased ACH in resident rooms (−9.5 ACH, 95% CI, −0.2 to −18.9) and resident washrooms (−7.0 ACH, 95% CI, −1.3 to −12.7). The absence of ducted air source was associated with decreased ACH in resident rooms (−12.2 ACH, 95% CI, −1.0 to −23.5).

Across 15 CLS, we identified readily actionable targets for improvements to ventilation. Based on our findings, we propose assessment criteria to optimize the performance of existing AHU. Prospective studies evaluating the impact of a standardized approach to improving AHU on safety of CLS residents are needed.

To assess preparedness for Candida auris in Canadian hospitals.

Cross-sectional survey.

Canadian Nosocomial Infection Surveillance Program (CNISP) hospitals.

In June 2024, surveys were e-mailed to the infection prevention and control departments of 109 CNISP hospitals and their 33 microbiology laboratories. The surveys assessed policies for patient screening/management and laboratory processes supporting C. auris transmission prevention. Results were compared to a similar 2018 survey.

All 109 hospitals and 32/33 laboratories responded. Most hospitals had policies for admission screening (80%, 87/109) and policies/defined plans for post-exposure screening (95%, 104/109). Policy presence increased from 18% to 73% in 56 hospitals completing both 2018 and 2024 surveys (P < 0.001). Among hospitals with admission screening policies, 69% (60/87) screened for recent out-of-country hospitalization. All but one hospital implemented transmission-based precautions for cases; 70% (76/109) continued precautions indefinitely. Overall, 94% (99/105; excluding hospitals with exclusively private rooms) and 55% (60/109) of hospitals screened roommates and wardmates, respectively. Frequency and timing of screening and policies regarding precautions for exposed patients varied. All hospitals used axilla and groin swabs, at minimum, for screening. Most (81%, 26/32) laboratories identified all clinically significant Candida isolates to species level, increasing from 48% to 85% (P < 0.001) in the 27 laboratories completing both 2018 and 2024 surveys. Twenty-four laboratories (75%) had standard operating procedures for processing screening specimens; 96% (23/24) used direct plating onto chromogenic agar.

Despite progress in C. auris preparedness, areas for improvement remain. Variability in practice may be related to evidence gaps and resource constraints.

Staphylococcus aureus is a common pathogen that can cause nosocomial infection. Ethyl alcohol has emerged as a potential alternative to mupirocin and povidone-iodine for nasal decolonization; however, data on real-world application are limited.

A quasi-experiment study was performed. Twice daily 62% ethyl alcohol nasal swabs were offered to inpatients at risk for MRSA acquisition. Compliance was monitored and reasons for non-adherence were evaluated. Rates of hospital-onset S. aureus bacteremia were compared pre and postintervention.

A total of 274,999 doses of ethyl alcohol were administered to 12,179 high-risk inpatients with a compliance rate of 82.7%. Reasons for non-compliance centered on product characteristics, patient comorbidities, and perceived lack of benefit from patients and healthcare personnel. There were fewer overall hospital-onset S. aureus bacteremia events (1.97 events/10,000 patients days predecolonization compared to 1.49 events/10,000 patient days with decolonization, P = .013). This difference was primarily driven by reduced MRSA bacteremia events (0.61 events/10,000 patient days predecolonization versus 0.36 with decolonization, P = .009) rather than MSSA bacteremia events (1.31 events/10,000 patient days predecolonization versus 1.13 events/10,000 patient days with decolonization, P = .232). On a per-patient basis during the intervention period, there were fewer MRSA bacteremia events in patients receiving decolonization (6.57 events per 10,000 patients) compared to high-risk, but eligible, patients who did not receive decolonization (19.62 episodes per 10,000 patients, P = .044).

Twice daily ethyl alcohol nasal treatment may be a viable alternative to existing S. aureus nasal decolonization options.

Describe the first healthcare-associated outbreak of Candida auris in Maricopa County, Arizona. Also, outline the Maricopa County Department of Public Health (MCDPH) response activities to halt transmission and identify affected healthcare facilities (HCFs) and contacts colonized with C. auris.

At HCFs with confirmed C. auris cases (i.e., exposed HCFs), MCDPH provided virtual infection control assessment and response activities, including contact investigations among hospitalized patients and point prevalence surveys (PPSs) to identify ongoing transmission. Confirmed C. auris cases included C. auris detected by cultures or polymerase chain reaction (PCR) in a hospitalized patient. Clinical cases had C. auris from cultures obtained during routine care in a hospitalized patient. Colonized cases included C. auris detected by PCR obtained from hospitalized patients for screening purposes.

On April 21, 2022, the first clinical case was identified, resulting in an outbreak with C. auris screening at 28 exposed HCFs. In total, 39 clinical C. auris cases were reported. Among 1,994 contacts identified, 899 (45.0%) were screened, 8 (0.4%) declined screening, and 1,087 (54.5%) were ineligible for screening (i.e., no longer hospitalized in Maricopa County). Among screened patients, 158 (17.6%) were colonized with C. auris; 15 (9.5%) colonized contacts later acquired clinical infections. This outbreak concluded on February 23, 2023, after 2 consecutive PPSs yielded no C. auris detection at exposed HCFs.

The first C. auris outbreak in Maricopa County highlights the coordinated efforts between HCFs, laboratories, and public health to identify exposed HCFs, screen contacts, and halt C. auris transmission.

Single-use supplies stored in bedside supply carts with paper packaging cannot be wiped with disinfectants. We aimed to determine the prevalence of pathogens on these unused supplies.

Prospective study over 7 weeks in 2025.

Two pediatric ICUs at a university affiliated children’s hospital.

The unit of analysis was the bedside supply cart from each discharged ICU patient.

One swab was used to swab three supply items contained in a single drawer in a room’s bedside cart. Carts had two drawers sampled, each with a swab for bacterial culture and respiratory viral nucleic acid amplification testing (NAAT).

Paper-packaged supply items (n = 840) from 70 consecutive bedside carts were swabbed after patient discharge. All bacterial swabs had no growth of pathogen [0/140 (0%), 95% CI 0%, 2.3%)]. A non-pathogen was cultured from 8/140 (5.7%) swabs [7/70 (10.0%) carts], most with scant growth [7/8 (87.5%) only one colony]. Non-pathogens (common commensal skin and oral flora) included coagulase-negative staphylococci (n = 5), Actinomyces oris (n = 1), aerobic spore-forming Bacillus (n = 1), and viridans group streptococcus [non-anginosus] (n = 1). Of viral swabs, 3/140 (2.1%, 95% CI 0.5%, 6.4%) were NAAT positive (3/70 (4.3%) carts). Room isolation status, length of stay, and ICU were not associated with a positive bacterial or viral swab.

Bacterial pathogen detection on supplies, a necessary step in transmission, was extremely low. Viral NAAT detection on supplies was low and likely exaggerated the risk of fomite transmission, as whether there was viable virus at sufficient concentration to transmit infection is unknown.

Carbapenem-resistant Acinetobacter baumannii (CRAB) is a major challenge, yet the role of hospital-wide active surveillance cultures (ASC) outside outbreak settings remains debated. We assessed the impact of targeted ASC and cohorting integrated with an established infection prevention and control (IPC) program in an endemic setting on CRAB epidemiology.

A retrospective study was conducted at a 515-bed university hospital in Israel (January 2016–August 2025; 2020–2021 excluded). Screening of high-risk patients commenced in January 2023 utilizing four-limb skin sponges, with comprehensive implementation and patient cohorting initiated in July 2023. Outcomes were CRAB present on admission (POA) and hospital-acquired CRAB (overall and clinical subsets). We fit quasi-Poisson ITS models (January 2022–August 2025) with log link and exposure offsets (admissions for POA; hospital days for acquired); total counts were modeled with negative binomial regression. Cases averted were estimated with rate-based and ITS counterfactuals.

POA detection increased markedly after screening implementation (median 0.72 to 2.98 per 1,000 admissions), revealing a large reservoir of admission carriage. Overall hospital-acquired CRAB rates showed no sustained decline. In contrast, hospital-acquired clinical-CRAB fell substantially after July 2023 (mean 3.93 to 0.97 per 10,000 hospital-days), with a marked post-intervention level reduction in the ITS model (Incidence-rate ratio (IRR) 0.224, 95% CI 0.071–0.072, P = .0103). Counterfactual analyses estimated approximately 60–70 hospital-acquired clinical CRAB cases averted during follow-up.

In an endemic setting, hospital-wide ASC targeting high-risk patients unmasked extensive admission carriage and, combined with cohorting and other IPC measures, was associated with a substantial reduction in acquired clinical-CRAB cases.

Investigate the increased incidence of Mycobacterium chelonae positive respiratory cultures in hospitalized patients.

Apply the Healthcare-Associated Links in Transmission of Nontuberculous Mycobacteria (HALT NTM) toolkit to an outbreak investigation of M. chelonae.

Quaternary-care pediatric hospital and medical center in the United States with a recently opened LEED-certified critical care tower.

Adult and pediatric patients with M. chelonae positive respiratory cultures between June 2022 and January 2024.

An epidemiological investigation involving clinical and laboratory practices, water management, building construction and renovation projects. Environmental sampling of air vents, water sources and endoscope reprocessing equipment was performed. M. chelonae isolates recovered from patients and the environment were analyzed using whole genome sequencing and compared for relatedness.

Three clusters of matching environmental and patient isolates were identified. The most common environmental source of M. chelonae was ice/water dispensers with 40% positivity of sampled units. The critical care tower’s water system performance and metrics were suboptimal, leading to four physical remediation activities along with a hyperchlorination treatment.

Recent and ongoing construction along with the implementation of a LEED-certified, low-flow water system in a new critical care tower provided enhanced opportunities for M. chelonae exposure at point of use locations such as ice/water dispensers. More national infection prevention and control guidance is needed to address the infection risks from water sustainability efforts and construction activities in healthcare facilities.

Data demonstrating a reduction in the incidence of nosocomial legionellosis following chlorine treatment are limited. Therefore, we aimed to evaluate the effectiveness of chlorine treatment by comparing the incidence of nosocomial legionellosis before and after the installation of a chlorine concentration control system.

A quasi-experimental study.

A 2,700-bed tertiary care hospital in Seoul, South Korea.

An automatic chlorine concentration control system was sequentially installed in the hospital’s water supply networks across multiple buildings between April 2019 and February 2020. The preintervention period was defined as January 2011 through March 2019, and the postintervention period as May 2020 through November 2025. Incidence rates of nosocomial legionellosis were compared between the two periods using exact Poisson methods.

The incidence of nosocomial legionellosis was found to be 0.402 per 100,000 patient-days during the preintervention period and 0.181 per 100,000 patient-days during the postintervention period. The incidence rate ratio for legionellosis during the postintervention period compared with the preintervention period was 0.45 (95% confidence interval, 0.18–1.01; P = .043).

The implementation of chlorine treatment in the hospital water distribution system was associated with a significant reduction in the incidence of nosocomial legionellosis. This finding provides long-term, real-world evidence supporting chlorine treatment as an effective water management strategy for preventing healthcare-associated legionellosis.

The impact of adopting the proposed National HealthCare Safety Network healthcare facility-onset antibiotic-treated Clostridioides difficile infection (HT-CDI) surveillance definition on the number of CDI cases that would qualify for healthcare-associated infection (HAI) surveillance reporting from US Veterans Affairs (VA) facilities is unknown.

We retrospectively evaluated CDI cases from 25 acute care VA medical centers from July 2022 through June 2024 using the proposed HT-CDI surveillance definition.

A total of 789 cases were analyzed. Use of the HT-CDI surveillance definition increased the number of reportable CDI HAIs by 23%.

In VA, adoption of the proposed HT-CDI surveillance definition increased the number of reportable cases.

Blood culture over-ordering is a recognized diagnostic stewardship challenge, contributing to contamination, inappropriate antimicrobial escalation, and laboratory burden. Validated tools to guide culture ordering at initial patient assessment are lacking.

We aim to derive and externally validate a two-step diagnostic stewardship rule for blood culture ordering in the emergency department (ED) patients with suspected infection.

We derived the Stepwise Culture Assessment with NEWS and NLR in ED (SCANNED) rule using consecutive blood cultures from a Singapore ED (April–July 2025) and validated it in Vancouver, Canada (2016–2019). The rule uses age-stratified National Early Warning Score (NEWS) thresholds (Step 1), followed by neutrophil-lymphocyte ratio (NLR) ≥5 for remaining patients (Step 2). Thresholds were selected via exhaustive grid search, optimizing culture reduction while constraining the false-negative rate to <5%.

We included 1,224 derivation and 808 validation encounters. Blood culture positivity was 9.6% (117/1,224) and 13.8% (112/808), respectively. The optimal rule (NEWS ≥5 if age <75 or NEWS ≥3 if age ≥75; NLR ≥5 for remainder) reduced cultures by 18.8% (95% CI 16.6–20.9%) in derivation and 15.1% (95% CI 12.8–17.6%) in validation, missing <5% of bacteremia cases in both cohorts. Performance was consistent across infection sources, including unclear/occult infections (17.5% reduction, 3.7% false-negative rate).

The SCANNED rule represents a practical diagnostic stewardship intervention that can reduce unnecessary blood cultures by 15–19% while maintaining >95% sensitivity for bacteremia. It requires no electronic health record integration and can be applied at triage. Prospective validation is needed before clinical implementation.

Outbreak investigation and control are critical for preventing the spread of infectious diseases in healthcare settings. Traditional methods rely on manual processes, which are time-consuming and limited in scope. Whole genome sequencing (WGS) surveillance improves outbreak detection but still requires extensive manual chart reviews to identify transmission routes. Integrating artificial intelligence (AI) may enhance the efficiency and accuracy of these investigations.

We evaluated an AI tool developed to streamline healthcare outbreak investigations detected by the Enhanced Detection System for Healthcare-associated Transmission (EDS-HAT). For outbreaks detected between November 2021 and November 2023, multiple data elements were extracted from electronic health records (EHR) for all patients. The AI algorithm was applied to identify transmission routes, and its performance was assessed against expert manual reviews. Key measures included additional transmission routes identified and sensitivity.

Data from 172 outbreaks involving 476 case patients were analyzed. The AI tool identified 37 transmission routes that were missed by manual review, including procedures and provider routes. The algorithm achieved a sensitivity of 76.0% (95% confidence interval [CI] 71.1%–81.1%) compared to manual review, increasing to 91.7% (95% CI 87.7%–94.7%) after accounting for transmission at other facilities and downstream exposures.

The EDS-HAT AI tool significantly improved outbreak investigations by automating the identification of transmission routes, both with concordant findings of manual review as well as finding additional routes of transmission missed by traditional chart review. AI with genomic surveillance has the potential to optimize outbreak detection and investigation to streamline interventions in healthcare settings.