Estimate the risk for household transmission of Methicillin-Resistant Staphylococcus aureus (MRSA) following exposure to infected family members or family members recently discharged from a hospital.

Analysis of monthly MRSA incidence from longitudinal insurance claims using the Merative MarketScan Commercial and Medicare (2001–2021) databases.

Visits to inpatient, emergency department, and outpatient settings.

Households with ≥2 family members enrolled in the same insurance plan for the entire month.

We estimated a monthly incidence model, where enrollees were binned into monthly enrollment strata defined by demographic, patient, and exposure characteristics. Monthly incidence within each stratum was computed, and a regression analysis was used to estimate the incidence rate ratio (IRR) associated with household exposures of interest while accounting for potential confounding factors.

A total of 157,944,708 enrollees were included and 424,512 cases of MRSA were identified. Across all included enrollees, exposure to a family member with MRSA in the prior 30 days was associated with significantly increased risk of infection (IRR: 71.03 [95% CI, 67.73–74.50]). After removing enrollees who were hospitalized or exposed to a family member with MRSA, exposure to a family member who was recently discharged from the hospital was associated with increased risk of infection (IRR: 1.44 [95% CI, 1.39–1.49]) and the risk of infection increased with the duration of the family member’s hospital stay (P value < .001).

Exposure to a recently hospitalized and discharged family member increased the risk of MRSA infection in a household even when the hospitalized family member was not diagnosed with MRSA.

To evaluate the economic costs of reducing the University of Virginia Hospital’s present “3-negative” policy, which continues methicillin-resistant Staphylococcus aureus (MRSA) contact precautions until patients receive 3 consecutive negative test results, to either 2 or 1 negative.

Cost-effective analysis.

The University of Virginia Hospital.

The study included data from 41,216 patients from 2015 to 2019.

We developed a model for MRSA transmission in the University of Virginia Hospital, accounting for both environmental contamination and interactions between patients and providers, which were derived from electronic health record (EHR) data. The model was fit to MRSA incidence over the study period under the current 3-negative clearance policy. A counterfactual simulation was used to estimate outcomes and costs for 2- and 1-negative policies compared with the current 3-negative policy.

Our findings suggest that 2-negative and 1-negative policies would have led to 6 (95% CI, −30 to 44; P < .001) and 17 (95% CI, −23 to 59; −10.1% to 25.8%; P < .001) more MRSA cases, respectively, at the hospital over the study period. Overall, the 1-negative policy has statistically significantly lower costs ($628,452; 95% CI, $513,592–$752,148) annually (P < .001) in US dollars, inflation-adjusted for 2023) than the 2-negative policy ($687,946; 95% CI, $562,522–$812,662) and 3-negative ($702,823; 95% CI, $577,277–$846,605).

A single negative MRSA nares PCR test may provide sufficient evidence to discontinue MRSA contact precautions, and it may be the most cost-effective option.

Klebsiella pneumoniae are common pathogens causing bloodstream infection (BSI) that increasingly express carbapenem resistance worldwide. To date, no study has precisely investigated the impact of carbapenem resistance in K. pneumoniae (CRKP) BSI on mortality.

This retrospective study included 87 patients with CRKP BSI and 321 patients with carbapenem-susceptible K. pneumoniae (CSKP) BSI from 2015 to 2020. Propensity score analyses with stabilized inverse probability of treatment weighting (IPTW-S) was applied to balance covariates. The hazard ratio for 30-day mortality associated with carbapenem resistance was estimated using Cox regression and Kaplan-Meier curves.

The 30-day crude mortality rates were 43.7% in patients with CRKP BSI and 17.8% in patients with CSKP BSI (P < .001). Age ≥55 years, underlying hematological malignancies and hemodialysis were independently associated with mortality in CRKP BSI. A skin or soft-tissue infection source, urinary catheter, and underlying chronic obstructive pulmonary disease were predictors of mortality in CSKP BSI. The group characteristics were well balanced after IPTW-S. The adjusted hazard ratio for 30-day mortality for CRKP BSI was 1.607 (interquartile range, 0.814–3.171).

Carbapenem resistance was not associated with a significant increase in 30-day mortality in KP BSI; patient and disease factors were primary determinants of outcomes.

To evaluate the impact of an intervention to limit dispersal from wastewater drain (WWD) sites on meropenem-nonsusceptible Pseudomonas aeruginosa patient and environmental colonization and bloodstream infection (BSI) on a hematopoietic cell transplant (HCT) and hematologic malignancy (HM) unit.

This quasi-experimental study included pre/postintervention point-prevalence surveys in July 2019 and June 2020, respectively. The retrospective cohort included HCT/HM patients with P. aeruginosa BSI between 2012 and 2022.

Adult HCT/HM unit at an academic center.

This study included consenting HCT/HM patients on the unit at the time of the point-prevalence surveys. HCT/HM patients with P. aeruginosa BSI between 2012 and 2022.

A quality improvement intervention targeting WWD sites was conceived and implemented on a HCT/HM unit. Pre and postintervention colonization samples were obtained from patients and environmental sites, cultivated on selective media, then characterized by susceptibility testing. Whole-genome sequencing and phylogenetic analysis were performed on select isolates. The impact of the intervention on colonization and BSI was evaluated, as was relatedness among isolates.

Although colonization of WWD sites with meropenem-nonsusceptible P. aeruginosa was widespread before and after this intervention, we observed a substantial decline in patient colonization (prevalence rate ratio, 0.35; 95% confidence interval [CI], 0.04–3.12) and BSI (incidence rate ratio, 0.67; 95% CI, 0.31–1.42) after the intervention. Among 3 predominant sequence types (ST-111, ST-446, and ST-308), there was striking genetic conservation within groups and among environmental colonization, patient colonization, and BSI isolates.

An intervention targeting WWD sites on a HCT/HM unit had a meaningful impact on meropenem-nonsusceptible P. aeruginosa patient colonization and BSI.

Emerging multidrug-resistant organisms (MDROs), such as carbapenem-resistant Enterobacterales (CRE), can spread rapidly in a region. Facilities that care for high-acuity patients with longer stays may have a disproportionate impact on this spread.

We assessed the impact of implementing preventive interventions, directed at a subset of facilities, on regional prevalence.

We developed a deterministic compartmental model, parametrized using CRE and patient transfer data. The model included the community and healthcare facilities within a US state. Individuals may be either susceptible or infectious with CRE. Individuals determined to be infectious through admission screening, periodic prevalence surveys (PPSs), or interfacility communication were placed in a state of lower transmissibility if enhanced infection prevention and control (IPC) practices were in place at a facility.

Intervention bundles that included PPS and enhanced IPC practices at ventilator-capable skilled nursing facilities (vSNFs) and long-term acute-care hospitals (LTACHs) had the greatest impact on regional prevalence. The benefits of including targeted admission screening in acute-care hospitals, LTACHs, and vSNFs, and improved interfacility communication were more modest. Daily transmissions in each facility type were reduced following the implementation of interventions primarily focused at LTACHs and vSNFs.

Our model suggests that interventions that include screening to limit unrecognized MDRO introduction to, or dispersal from, LTACHs and vSNFs slow regional spread. Interventions that pair detection and enhanced IPC practices within LTACHs and vSNFs may substantially reduce the regional burden.

To describe the relative burden of catheter-associated urinary tract infections (CAUTIs) and non-CAUTI hospital-onset urinary tract infections (HOUTIs).

A retrospective observational study of patients from 43 acute-care hospitals was conducted. CAUTI cases were defined as those reported to the National Healthcare Safety Network. Non-CAUTI HOUTI was defined as a positive, non-contaminated, non-commensal culture collected on day 3 or later. All HOUTIs were required to have a new antimicrobial prescribed within 2 days of the first positive urine culture. Outcomes included secondary hospital-onset bacteremia and fungemia (HOB), total hospital costs, length of stay (LOS), readmission risk, and mortality.

Of 549,433 admissions, 434 CAUTIs and 3,177 non-CAUTI HOUTIs were observed. The overall rate of HOB likely secondary to HOUTI was 3.7%. Total numbers of secondary HOB were higher in non-CAUTI HOUTIs compared to CAUTI (101 vs 34). HOB secondary to non-CAUTI HOUTI was more likely to originate outside the ICU compared to CAUTI (69.3% vs 44.1%). CAUTI was associated with adjusted incremental total hospital cost and LOS of $9,807 (P < .0001) and 3.01 days (P < .0001) while non-CAUTI HOUTI was associated with adjusted incremental total hospital cost and LOS of $6,874 (P < .0001) and 2.97 days (P < .0001).

CAUTI and non-CAUTI HOUTI were associated with deleterious outcomes. Non-CAUTI HOUTI occurred more often and was associated with a higher facility aggregate volume of HOB than CAUTI. Patients at risk for UTIs in the hospital represent a vulnerable population who may benefit from surveillance and prevention efforts, particularly in the non-ICU setting.

Compare the effectiveness of multiple mitigation measures designed to protect nursing home residents from infectious disease outbreaks.

Agent-based simulation study.

Simulation environment of a small nursing home.

We collected temporally detailed and spatially fine-grained location information from nursing home healthcare workers (HCWs) using sensor motes. We used these data to power an agent-based simulation of a COVID-19 outbreak using realistic time-varying estimates of infectivity and diagnostic sensitivity. Under varying community prevalence and transmissibility, we compared the mitigating effects of (i) regular screening and isolation, (ii) inter-resident contact restrictions, (iii) reduced HCW presenteeism, and (iv) modified HCW scheduling.

Across all configurations tested, screening every other day and isolating positive cases decreased the attack rate by an average of 27% to 0.501 on average, while contact restrictions decreased the attack rate by an average of 35%, resulting in an attack rate of only 0.240, approximately half that of screening/isolation. Combining both interventions impressively produced an attack rate of only 0.029. Halving the observed presenteeism rate led to an 18% decrease in the attack rate, but if combined with screening every 6 days, the effect of reducing presenteeism was negligible. Altering work schedules had negligible effects on the attack rate.

Universal contact restrictions are highly effective for protecting vulnerable nursing home residents, yet adversely affect physical and mental health. In high transmission and/or high community prevalence situations, restricting inter-resident contact to groups of 4 was effective and made highly effective when paired with weekly testing.

To synthesize evidence and identify gaps in the literature on environmental cleaning and disinfection in the operating room based on a human factors and systems engineering approach guided by the Systems Engineering Initiative for Patient Safety (SEIPS) model.

A systematic scoping review.

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched 4 databases (ie, PubMed, EMBASE, OVID, CINAHL) for empirical studies on operating-room cleaning and disinfection. Studies were categorized based on their objectives and designs and were coded using the SEIPS model. The quality of randomized controlled trials and quasi-experimental studies with a nonequivalent groups design was assessed using version 2 of the Cochrane risk-of-bias tool for randomized trials.

In total, 40 studies were reviewed and categorized into 3 groups: observational studies examining the effectiveness of operating-room cleaning and disinfections (11 studies), observational study assessing compliance with operating-room cleaning and disinfection (1 study), and interventional studies to improve operating-room cleaning and disinfection (28 studies). The SEIPS-based analysis only identified 3 observational studies examining individual work-system components influencing the effectiveness of operating-room cleaning and disinfection. Furthermore, most interventional studies addressed single work-system components, including tools and technologies (20 studies), tasks (3 studies), and organization (3 studies). Only 2 studies implemented interventions targeting multiple work-system components.

The existing literature shows suboptimal compliance and inconsistent effectiveness of operating-room cleaning and disinfection. Improvement efforts have been largely focused on cleaning and disinfection tools and technologies and staff monitoring and training. Future research is needed (1) to systematically examine work-system factors influencing operating-room cleaning and disinfection and (2) to redesign the entire work system to optimize operating-room cleaning and disinfection.

The US National Action Plan for Combating Antibiotic-Resistant Bacteria established a goal to decrease unnecessary outpatient antibiotic use by 50%. However, data to inform this goal have been limited to medical settings and have not included dental prescribing. Thus, we sought to identify the proportion of antibiotics prescribed inappropriately by dentists to inform outpatient stewardship efforts.

Cross-sectional analysis of 2019 Veterans’ Affairs (VA) national electronic health record data. Antibiotics prescribed by dentists were evaluated for appropriateness based on 2 definitions: one derived from current guidelines (consensus-based recommendations) and the other based on relevant clinical literature (nonconsensus). A clustered binomial logistic regression model determined factors associated with discordant prescribing.

In total, 92,224 antibiotic prescriptions (63% amoxicillin; mean supply, 8.0 days) were associated with 88,539 dental visits. Prophylaxis for complications in medically compromised patients was associated with the most (30.9%) antibiotic prescriptions, followed by prevention of postsurgical complications (20.1%) and infective endocarditis (18.0%). At the visit level, 15,476 (17.5%) met the consensus-based definition for appropriate antibiotic usage and 56,946 (64.3%) met the nonconsensus definition.

More than half of antibiotics prescribed by dentists do not have guidelines supporting their use. Regardless of definition applied, antibiotics prescribed by dentists were commonly unnecessary. Improving prescribing by dentists is critical to reach the national goal to decrease unnecessary antibiotic use.