To evaluate the impact of administering probiotics to prevent Clostridioides difficile infection (CDI) among patients receiving therapeutic antibiotics.

Stepped-wedge cluster-randomized trial between September 1, 2016, and August 31, 2019.

This study was conducted in 4 acute-care hospitals across an integrated health region.

Hospitalized patients, aged ≥55 years.

Patients were given 2 probiotic capsules daily (Bio-K+, Laval, Quebec, Canada), containing 50 billion colony-forming units of Lactobacillus acidophilus CL1285, L. casei LBC80R, and L. rhamnosus CLR2. We measured hospital-acquired CDI (HA-CDI) and the number of positive C. difficile tests per 10,000 patient days as well as adherence to administration of Bio-K+ within 48 and 72 hours of antibiotic administration. Mixed-effects generalized linear models, adjusted for influenza admissions and facility characteristics, were used to evaluate the impact of the intervention on outcomes.

Overall adherence of Bio-K+ administration ranged from 76.9% to 84.6% when stratified by facility and periods. Rates of adherence to administration within 48 and 72 hours of antibiotic treatment were 60.2% –71.4% and 66.7%–75.8%, respectively. In the adjusted analysis, there was no change in HA-CDI (incidence rate ratio [IRR], 0.92; 95% confidence interval [CI], 0.68–1.23) or C. difficile positivity rate (IRR, 1.05; 95% CI, 0.89–1.24). Discharged patients may not have received a complete course of Bio-K+. Our hospitals had a low baseline incidence of HA-CDI. Patients who did not receive Bio-K+ may have differential risks of acquiring CDI, introducing selection bias.

Hospitals considering probiotics as a primary prevention strategy should consider the baseline incidence of HA-CDI in their population and timing of probiotics relative to the start of antimicrobial administration.

Evidence-based central-line–associated bloodstream infection (CLABSI) prevention guidelines recommend the use of an antiseptic scrub to disinfect needleless connectors before device access. Guideline noncompliance may render disinfection ineffective. The goal of this study was to observe needleless-connector disinfection practices and to identify perceived facilitators and barriers to best practices of needleless-connector access.

A human factors mixed-methods study involving nursing focus groups of perceived barriers and facilitators and clinical observations of compliance with instructions and protocols for use of 3.15% chlorhexidine gluconate/70% isopropyl alcohol (CHG/IPA) and 70% isopropyl alcohol (IPA) antisepsis products for central venous access device (CVAD) needleless-connector disinfection was conducted in intensive care units (ICUs) at 2 academic medical centers.

Access to the antiseptic product and lesser workload were identified as best-practice facilitators. Barriers were the time required per needleless-connector access and knowledge deficits. Of the 48 observed access events, 77% resulted in needleless-connector disinfection. The observed mean needleless-connector scrubbing times when using IPA were substantially below the recommended time. Drying time after product use was negligible.

Lack of access to the disinfection product, emergency situations, and high workload were barriers to needleless-connector disinfection. Observed scrubbing and drying times were shorter than recommended, especially for IPA wipes. These needleless-connector disinfection deficits may increase the risk of CLABSI. Ongoing education and periodic competency evaluation of needleless-connector disinfection, improvement of supply management, and staffing workload are required to imbed and sustain best practices. Further study involving a larger sample size in diverse patient populations is warranted.

To systematically review the methodology, performance, and generalizability of diagnostic models for predicting the risk of healthcare-facility–onset (HO) Clostridioides difficile infection (CDI) in adult hospital inpatients (aged ≥18 years).

CDI is the most common cause of healthcare-associated diarrhea. Prediction models that identify inpatients at risk of HO-CDI have been published; however, the quality and utility of these models remain uncertain.

Two independent reviewers evaluated articles describing the development and/or validation of multivariable HO-CDI diagnostic models in an inpatient setting. All publication dates, languages, and study designs were considered. Model details (eg, sample size and source, outcome, and performance) were extracted from the selected studies based on the CHARMS checklist. The risk of bias was further assessed using PROBAST.

Of the 3,030 records evaluated, 11 were eligible for final analysis, which described 12 diagnostic models. Most studies clearly identified the predictors and outcomes but did not report how missing data were handled. The most frequent predictors across all models were advanced age, receipt of high-risk antibiotics, history of hospitalization, and history of CDI. All studies reported the area under the receiver operating characteristic curve (AUROC) as a measure of discriminatory ability. However, only 3 studies reported the model calibration results, and only 2 studies were externally validated. All of the studies had a high risk of bias.

The studies varied in their ability to predict the risk of HO-CDI. Future models will benefit from the validation on a prospective external cohort to maximize external validity.

The Concurrent Approach for Respiratory Epidemiological Surveillance and Symptom Screening (CARES) combines symptom screening to prevent external respiratory infections by managing staff and visitor health and surveillance to monitor the infection rates within the facility and take timely decisions on activity programs based on outbreak prevalence. This study examines the efficacy of the CARES strategy in preventing respiratory infection outbreaks in long-term care facilities.

Prospective cohort study utilizing historical controls including an intervention and control group.

This study was conducted in two long-term care facility wards (total: 110 beds) in Japan.

We enrolled patients aged 1–72 years from the target ward with severe intellectual and physical disabilities from October 1, 2018, to March 31, 2019, and from October 1, 2017, to March 31, 2018, for the intervention (n = 104) and control (n = 98) groups, respectively. The study included all admitted patients and excluded those hospitalized or discharged during the study period.

The total number of days that activity programs, new admissions, and visitations were cancelled in the two groups was compared before and after the introduction of CARES.

CARES reduced the duration of new admission cancellations and visitation cancellations by 16 and 23 days, respectively (α = 0.1, P value < 0.001). Additionally, the maximum duration of activity program cancellations was reduced by 2 days. Furthermore, five cases of presenteeism were prevented.

CARES improves patients’ quality of life by continuation of activity programs, new patient admission, and ongoing visitations.

To characterize the relationship between chlorhexidine gluconate (CHG) skin concentration and skin microbial colonization.

Serial cross-sectional study.

Adult patients in medical intensive care units (ICUs) from 7 hospitals; from 1 hospital, additional patients colonized with carbapenemase-producing Enterobacterales (CPE) from both ICU and non-ICU settings. All hospitals performed routine CHG bathing in the ICU.

Skin swab samples were collected from adjacent areas of the neck, axilla, and inguinal region for microbial culture and CHG skin concentration measurement using a semiquantitative colorimetric assay. We used linear mixed effects multilevel models to analyze the relationship between CHG concentration and microbial detection. We explored threshold effects using additional models.

We collected samples from 736 of 759 (97%) eligible ICU patients and 68 patients colonized with CPE. On skin, gram-positive bacteria were cultured most frequently (93% of patients), followed by Candida species (26%) and gram-negative bacteria (20%). The adjusted odds of microbial recovery for every twofold increase in CHG skin concentration were 0.84 (95% CI, 0.80–0.87; P < .001) for gram-positive bacteria, 0.93 (95% CI, 0.89–0.98; P = .008) for Candida species, 0.96 (95% CI, 0.91–1.02; P = .17) for gram-negative bacteria, and 0.94 (95% CI, 0.84–1.06; P = .33) for CPE. A threshold CHG skin concentration for reduced microbial detection was not observed.

On a cross-sectional basis, higher CHG skin concentrations were associated with less detection of gram-positive bacteria and Candida species on the skin, but not gram-negative bacteria, including CPE. For infection prevention, targeting higher CHG skin concentrations may improve control of certain pathogens.

Surveillance of hospital-acquired infections (HAIs) is the foundation of infection control. Machine learning (ML) has been demonstrated to be a valuable tool for HAI surveillance. We compared manual surveillance with a supervised, semiautomated, ML method, and we explored the types of infection and features of importance depicted by the model.

From July 2021 to December 2021, a semiautomated surveillance method based on the ML random forest algorithm, was implemented in a Brazilian hospital. Inpatient records were independently manually searched by the local team, and a panel of independent experts reviewed the ML semiautomated results for confirmation of HAI.

Among 6,296 patients, manual surveillance classified 183 HAI cases (2.9%), and a semiautomated method found 299 HAI cases (4.7%). The semiautomated method added 77 respiratory infections, which comprised 93.9% of the additional HAIs. The ML model considered 447 features for HAI classification. Among them, 148 features (33.1%) were related to infection signs and symptoms; 101 (22.6%) were related to patient severity status, 51 features (11.4%) were related to bacterial laboratory results; 40 features (8.9%) were related to invasive procedures; 34 (7.6%) were related to antibiotic use; and 31 features (6.9%) were related to patient comorbidities. Among these 447 features, 229 (51.2%) were similar to those proposed by NHSN as criteria for HAI classification.

The ML algorithm, which included most NHSN criteria and >200 features, augmented the human capacity for HAI classification. Well-documented algorithm performances may facilitate the incorporation of AI tools in clinical or epidemiological practice and overcome the drawbacks of traditional HAI surveillance.

We compared the number of blood-culture events before and after the introduction of a blood-culture algorithm and provider feedback. Secondary objectives were the comparison of blood-culture positivity and negative safety signals before and after the intervention.

Prospective cohort design.

Two surgical intensive care units (ICUs): general and trauma surgery and cardiothoracic surgery

Patients aged ≥18 years and admitted to the ICU at the time of the blood-culture event.

We used an interrupted time series to compare rates of blood-culture events (ie, blood-culture events per 1,000 patient days) before and after the algorithm implementation with weekly provider feedback.

The blood-culture event rate decreased from 100 to 55 blood-culture events per 1,000 patient days in the general surgery and trauma ICU (72% reduction; incidence rate ratio [IRR], 0.38; 95% confidence interval [CI], 0.32–0.46; P < .01) and from 102 to 77 blood-culture events per 1,000 patient days in the cardiothoracic surgery ICU (55% reduction; IRR, 0.45; 95% CI, 0.39–0.52; P < .01). We did not observe any differences in average monthly antibiotic days of therapy, mortality, or readmissions between the pre- and postintervention periods.

We implemented a blood-culture algorithm with data feedback in 2 surgical ICUs, and we observed significant decreases in the rates of blood-culture events without an increase in negative safety signals, including ICU length of stay, mortality, antibiotic use, or readmissions.

Recent work demonstrated that detection of SARS-CoV-2 on the floor of long-term care facilities is associated with impending COVID-19 outbreaks. It is unknown if similar results will be observed in hospitals.

Floor swabs were prospectively collected weekly from healthcare worker-only areas (eg, staff locker rooms) at two hospitals in Ontario, Canada for 39 weeks. Floor swabs were processed for SARS-CoV-2 using quantitative reverse-transcriptase polymerase chain reaction. Results were reported as percentage of positive floor swabs and viral copy number. Grouped fivefold cross-validation was used to evaluate model outbreak discrimination.

SARS-CoV-2 RNA was detected on 537 of 760 floor swabs (71%). At Hospital A, overall positivity was 90% (95% CI: 85%–93%; N = 280); at Hospital B, overall positivity was 60% (95% CI: 55%–64%; N = 480). There were four COVID-19 outbreaks at Hospital A and seven at Hospital B during the study period. The outbreaks consisted of primarily patient cases (ie, 140 patient cases and 4 staff cases). For every 10-fold increase in viral copies, there was a 22-fold higher odds of a COVID-19 outbreak (OR = 22.0, 95% CI 7.3, 91.8). The cross-validated area under the receiver operating curve for SARS-CoV-2 viral copies for predicting a contemporaneous outbreak was 0.86 (95% CI 0.82–0.90).

Viral burden of SARS-CoV-2 on floors, even in healthcare worker-only areas, was strongly associated with COVID-19 outbreaks in those hospital wards. Built environment sampling may support hospital COVID-19 outbreak identification, fill gaps in traditional surveillance, and guide infection prevention and control measures.

Monitoring antibiotic consumption is a key component to steer antimicrobial stewardship programs, including in nursing homes. We analyzed changes in antibiotic consumption in French nursing homes during 5 years, including the COVID-19 pandemic, to identify potential priorities for improvement.

A multicenter survey was conducted between 2018 and 2022.

The study was conducted across 220 French nursing homes with on-site pharmacies.

Antibiotic consumption data were collected from pharmacy records and are expressed as defined daily doses per 1,000 resident days. Antibiotic indicators promoted by health authorities were calculated from quantitative data to evaluate the quality of prescribing.

Antibiotic consumption significantly decreased between 2018 and 2022, particularly during the coronavirus disease 2019 (COVID-19) pandemic, despite a slight increase in 2022. During the study period, the most used antibiotic classes were penicillins (61.9% in 2022) followed by cephalosporins (10.5%), macrolides–lincosamides–streptogramins (7.3%) then fluoroquinolones (7.0%). Amoxicillin–clavulanic acid was the most consumed antibiotic; amoxicillin and ceftriaxone ranked second and third. Azithromycin consumption increased from 2020, as did the indicator regarding broad-spectrum antibiotics.

The decreasing trend in antibiotic use and control of fluoroquinolone use over the study period suggest compliance with antibiotic use guidelines. However, changes in the use of broad-spectrum antibiotics and the substantial use of amoxicillin-clavulanic acid, although it is rarely a first-line antibiotic, highlight the need for antimicrobial stewardship activities and the usefulness of antibiotic consumption surveillance to identify priorities.

Incidence and risk factors for recurrent Clostridioides difficile infection (rCDI) are well established in adults, though data are lacking in pediatrics. We aimed to determine incidence of and risk factors for rCDI in pediatrics.

This retrospective cohort study of pediatric patients was conducted at 3 tertiary-care hospitals in Canada with laboratory-confirmed CDI between April 1, 2012, and March 31, 2017. rCDI was defined as an episode of CDI occurring 8 weeks or less from diagnostic test date of the primary episode. We used logistic regression to determine and quantify risk factors significantly associated with rCDI.

In total, 286 patients were included in this study. The incidence proportion for rCDI was 12.9%. Among hospitalized patients, the incidence rate was estimated at 2.6 cases of rCDI per 1,000 hospital days at risk (95% confidence interval [CI], 1.7–3.9). Immunocompromised patients had higher incidence of rCDI (17.5%; P = .03) and higher odds of developing rCDI independently of antibiotic treatment given for the primary episode (odds ratio [OR], 2.31; 95% CI, 1.12–5.09). Treatment with vancomycin monotherapy did not show statistically significant protection from rCDI, independently of immunocompromised status (OR, 0.33; 95% CI, 0.05–1.15]).

The identification of increased risk of rCDI in immunocompromised pediatric patients warrants further research into alternative therapies, prophylaxis, and prevention strategies to prevent recurrent disease burden within these groups. Treatment of the initial episode with vancomycin did not show statistically significant protection from rCDI.

Determination of whether vascular catheter disinfecting antiseptic-containing caps alone are effective at decreasing microbial colonization of connectors compared to antiseptic-containing caps plus a 5-second alcohol manual disinfection.

The study was conducted in a 718-bed, tertiary-care, academic hospital.

A convenience sample of adult patients across intensive care units and acute care wards with peripheral and central venous catheters covered with antiseptic-containing caps.

Quality improvement study completed over 5 days. The standard-of-care group consisted of catheter connectors with antiseptic-containing caps cleaned with a 5-second alcohol wipe scrub prior to culture. The comparison group consisted of catheter connectors with antiseptic-containing caps without a 5-second alcohol wipe scrub prior to culture. The connectors were pressed directly onto blood agar plates and incubated. Plates were assessed for growth after 48-72 hours.

In total, 356 catheter connectors were cultured: 165 in the standard-of-care group, 165 in the comparison group, and 26 catheters connectors without an antiseptic-containing cap, which were designated as controls. Overall, 18 catheter connectors (5.06%) yielded microbial growth. Of the 18 connectors with microbial growth, 2 (1.21%) were from the comparison group, 1 (0.61%) was from the standard-of-care group, and 15 were controls without an antiseptic-containing cap.

Bacterial colonization rates were similar between the catheter connectors cultured with antiseptic-containing caps alone and catheter connectors with antiseptic-containing caps cultured after a 5-second scrub with alcohol. This finding suggests that the use of antiseptic-containing caps precludes the need for additional disinfection.

Awareness of health disparities’ impact on clinical outcomes is increasing. However, public health’s ability to highlight these trends can be limited by data missingness, such as on race and ethnicity. To better understand race and ethnicity’s impact, we compared all-cause 30-day mortality rates between non-Hispanic (NH) Black, NH White, and Hispanic/NH other racial and ethnic patients among cases of carbapenem-resistant Enterobacterales (CRE).

We performed data linkage using CRE statewide surveillance, Hospital Discharge Data System, and vital records data to obtain demographics and clinical outcomes on CRE cases in TN. We evaluated the association between race and ethnicity with all-cause 30-day mortality among CRE cases.

Among 2,804 reported CRE cases from 2015 to 2019, 65% (n = 1,832) were missing race and ethnicity; data linkage methods reduced missingness to 10% (n = 285). 22%, 74%, and 3% of cases were among NH Black, NH White, and Hispanic/NH other patients, respectively. Thirty-day all-cause mortality among NH Black patients was 5.7 per 100,000 population, 1.9 and 5.7 times higher than NH White and Hispanic/NH other patients. We observed that the risk of dying within 30 days of CRE diagnosis was 35% higher for NH Black compared to NH White patients; unmeasured confounders may be present (adjusted risk ratio 1.35; 95% CI 1.00, 1.83).

Data linkage effectively reduced missingness of race and ethnicity. Among those with CRE, NH Blacks may have an increased risk of all-cause 30-day mortality. Data missingness creates barriers in identifying health disparities; data linkage is one approach to overcome this challenge.

Whole-genome sequencing (WGS) has emerged as an alternative genotyping tool for outbreak investigations in the healthcare setting. We describe the investigation and control of a New Delhi metallo-B-lactamase (NDM)-producing Escherichia coli cluster in Southeast Michigan.

Michigan Bureau of Laboratories identified several closely related NDM-producing E. coli isolates with WGS. An epidemiologic investigation, including case-control study, assessment of infection control practices, and endoscope culturing, was performed to identify source of transmission. Targeted screening of potentially exposed patients was performed following identification of probable source.

Between July 2021 and February 2023, nine patients were identified. Phylogenetic analysis confirmed the isolates were closely related with less than 26 single nucleotide polymorphism (SNP) differences between isolates, suggesting an epidemiological link. Eight (89%) patients had a duodenoscope and/or gastroscope exposure. Cases were compared with 23 controls. Cases had significantly higher odds of exposure to duodenoscopes (odds ratio 15.0; 95% CI, 1.8–142.2; P = .015). The mean incubation period, estimated as date of procedure to positive index culture, was 86 days (range, 1–320 days). No lapses in endoscope reprocessing were identified; NDM-producing E. coli was not recovered from reprocessed endoscopes or during targeted screening. No additional cases were identified after removal of implicated gastroscopes and replacement of duodenoscope with disposable end caps.

In this investigation, WGS was utilized to identify transmission of an NDM-producing E. coli outbreak associated with endoscope exposure. Coupled with epidemiologic data, WGS can facilitate outbreak investigations by rapidly identifying linked cases and potential sources to prevent further transmission.

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.

In this study, we aim to estimate the risk of developing clinical multidrug-resistant organism (MDRO) infection with carbapenem-resistant Enterobacterales (CRE), methicillin-resistant Staphylococcus aureus (MRSA), or vancomycin-resistant enterococci (VRE) in colonized patients compared with non-colonized admitted to high-risk areas with a main focus on CRE colonization/infection.

Retrospective cohort study conducted at a tertiary care facility.

This study included patients enrolled in active surveillance testing (AST) for CRE, MRSA, or VRE during the year 2021. Development of relevant invasive infection within 365 days of the AST result was collected as the primary outcome. The association between MDRO colonization and infection was calculated using the risk ratio. The prevalence of CRE organisms and carbapenemase genes is presented.

A total of 19,134 ASTs were included in the analysis (4,919 CRE AST, 8,303 MRSA AST, and 5,912 VRE AST). Patient demographics were similar between colonized and non-colonized groups. Colonization was associated with an increased risk of infection in the 3 cohorts (CRE, MRSA, and VRE), with risk ratios reported as 4.6, 8.2, and 22, respectively. Most patients (88%) develop CRE infection with the same colonizing carbapenemase gene. Oxa-48/NDM Klebsiella pneumoniae was the most common organism detected in CRE infection.

The study demonstrated that colonization with CRE, MRSA, or VRE is a risk factor for developing infections caused by the respective bacteria. The high percentage of match between carbapenemase genes detected in colonization and infection indicates that screening results might be used to inform infection management and treatment.

To evaluate the risk of surgical site infection (SSI) following complicated appendectomy in individual patients receiving delayed primary closure (DPC) versus primary closure (PC) after adjustment for individual risk factors.

Secondary analysis of randomized controlled trial (RCT) with prediction model.

Referral centers across Thailand.

Adult patients who underwent appendectomy via a lower-right-quadrant abdominal incision due to complicated appendicitis.

A secondary analysis of a published RCT was performed applying a counterfactual prediction model considering interventions (PC vs DPC) and other significant predictors. A multivariable logistic regression was applied, and a likelihood-ratio test was used to select significant predictors to retain in a final model. Factual versus counterfactual SSI risks for individual patients along with individual treatment effect (iTE) were estimated.

In total, 546 patients (271 PC vs 275 DPC) were included in the analysis. The individualized prediction model consisted of allocated intervention, diabetes, type of complicated appendicitis, fecal contamination, and incision length. The iTE varied between 0.4% and 7% for PC compared to DPC; ∼38.1% of patients would have ≥2.1% lower SSI risk following PC compared to DPC. The greatest risk reduction was identified in diabetes with ruptured appendicitis, fecal contamination, and incision length of 10 cm, where SSI risks were 47.1% and 54.1% for PC and DPC, respectively.

In this secondary analysis, we found that most patients benefited from early PC versus DPC. Findings may be used to inform SSI prevention strategies for patients with complicated appendicitis.

US policies require robust nursing home (NH) infection prevention and control (IPC) programs to ensure safe care. We assessed IPC resources and practices related to catheter and non–catheter-associated urinary tract infection (CAUTI and UTI) prevention among NHs.

We conducted a mixed-methods study from April 2018 through November 2019. Quantitative surveys assessed NH IPC program resources, practices, and communication during resident transfer. Semistructured qualitative interviews focused on IPC programs, CAUTI and UTI prevention practices, and resident transfer processes. Using a matrix as an analytic tool, findings from the quantitative survey data were combined with the qualitative data in the form of a joint display.

Representatives from 51 NHs completed surveys; interviews were conducted with 13 participants from 7 NHs. Infection preventionists (IPs) had limited experience and/or additional roles, and in 36.7% of NHs, IPs had no specific IPC training. IP turnover was often mentioned during interviews. Most facilities were aware of their CAUTI and UTI rates and reported using prevention practices, such as hydration (85.7%) or nurse-initiated catheter discontinuation (65.3%). Qualitative interviewees confirmed use of these practices and expressed additional concerns about overuse of urine testing and antibiotics. Although transfer sheets were used by 84% to communicate about infections, the information received was described as suboptimal.

NHs identified IP challenges related to turnover, limited education, and serving multiple roles. However, most NHs reported awareness of their CAUTI and UTI rates as well as their use of prevention practices. Importantly, we identified opportunities to enhance communication between NHs and hospitals to improve resident care and safety.

The number of hospitalized patients with severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) does not differentiate between patients admitted due to coronavirus disease 2019 (COVID-19) (ie, primary cases) and incidental SARS-CoV-2 infection (ie, incidental cases). We developed an adaptable method to distinguish primary cases from incidental cases upon hospital admission.

Retrospective cohort study.

Data were obtained from 3 German tertiary-care hospitals.

The study included patients of all ages who tested positive for SARS-CoV-2 by a standard quantitative reverse-transcription polymerase chain reaction (RT-PCR) assay upon admission between January and June 2022.

We present 2 distinct models: (1) a point-of-care model that can be used shortly after admission based on a limited range of parameters and (2) a more extended point-of-care model based on parameters that are available within the first 24–48 hours after admission. We used regression and tree-based classification models with internal and external validation.

In total, 1,150 patients were included (mean age, 49.5±28.5 years; 46% female; 40% primary cases). Both point-of-care models showed good discrimination with area under the curve (AUC) values of 0.80 and 0.87, respectively. As main predictors, we used admission diagnosis codes (ICD-10-GM), ward of admission, and for the extended model, we included viral load, need for oxygen, leucocyte count, and C-reactive protein.

We propose 2 predictive algorithms based on routine clinical data that differentiate primary COVID-19 from incidental SARS-CoV-2 infection. These algorithms can provide a precise surveillance tool that can contribute to pandemic preparedness. They can easily be modified to be used in future pandemic, epidemic, and endemic situations all over the world.

To investigate the source and transmission dynamics of an endoscope-associated New Delhi metallo-β-lactamase-producing Klebsiella pneumonia (NDM-KP) outbreak.

Epidemiological and genomic investigation.

Academic acute care hospital in New Jersey.

Five patients with active NDM-KP infection identified on clinical isolates, and four NDM-KP colonized patients identified via rectal swab screening.

Over a twelve-month period, nine patients were identified with NDM-KP infection or colonization. Whole-genome sequencing (WGS) revealed that all of the identified cases were related by 25 mutational events or less. Seven of the cases were linked to gastrointestinal endoscopic procedures (four clinical cases and three positive screens among patients exposed to endoscopes suspected of transmission). Two cases demonstrated delayed transmission that occurred five months after the initial outbreak, likely through shared usage of a non-therapeutic gastroscope without an elevator channel.

Although all endoscope cultures in our investigation were negative, the epidemiological link to gastrointestinal endoscopes, the high degree of relatedness via WGS, and the identification of asymptomatic NDM-KP colonization among patients exposed to shared endoscopes make the endoscopic mode of transmission most likely. This investigation highlights the probable transmission of NDM-KP via a gastroscope without an elevator channel, observed several months after an initial outbreak. We hypothesize that persistent mechanical defects may have contributed to the delayed device-related transmission of NDM-KP.

To implement and evaluate a point-of-care (POC) molecular testing platform for respiratory viruses in congregate living settings (CLS).

Prospective quality improvement study.

Seven CLS, including three nursing homes and four independent-living facilities.

Residents of CLS.

A POC platform for COVID-19, influenza A and B, and respiratory syncytial virus was implemented at participating CLS from December 1, 2022 to April 15, 2023. Residents with respiratory symptoms underwent paired testing, with respiratory specimens tested first with the POC platform and then delivered to an off-site laboratory for multiplex respiratory virus panel (MRVP) polymerase chain reaction (PCR) as per standard protocol. Turn-around time and diagnostic accuracy of the POC platform were compared against MRVP PCR. In an exploratory analysis, time to outbreak declaration among participating CLS was compared against a convenience sample of 19 CLS that did not use the POC platform.

A total of 290 specimens that underwent paired testing were included. Turn-around time to result was significantly shorter with the POC platform compared to MRVP PCR, with median difference of 36.2 hours (interquartile range 21.8–46.4 hours). The POC platform had excellent diagnostic accuracy compared to MRVP PCR, with area under the curve statistic of .96. Time to outbreak declaration was shorter in CLS that used the POC platform compared to CLS that did not.

Rapid POC testing platforms for respiratory viruses can be implemented in CLS, with high diagnostic accuracy, expedited turn-around times, and shorter time to outbreak declaration.