Infection Control & Hospital Epidemiology

Objectives To evaluate two-year, side-by-side outcomes of a prospective audit and feedback (PAF)-based antimicrobial stewardship program (ASP) in a quaternary ICU in Ghana, comparing diagnostic stewardship, antimicrobial prescribing patterns, and clinician adherence to stewardship recommendations between 2024 and 2025. Longitudinal PAF data from low- and middle-income countries (LMIC) quaternary ICUs are scarce; this study addresses that evidence gap. Methods A retrospective comparative analysis of routine Antimicrobial Stewardship (AMS) surveillance data was conducted at the University of Ghana Medical Centre ICU: 102 visits in 2024 and 63 in 2025. Proportions were compared by chi-square or Fishers exact test; continuous variables by Mann-Whitney U. Wilson score 95% confidence intervals (CIs) were computed for primary proportions. Results Biomarker-guided prescribing rose from 86.3% to 100% of visits (p=0.005) and culture and sensitivity testing from 74.5% to 90.5% (p=0.02). Targeted (culture-guided) therapy increased significantly from 23.5% to 41.7% of antibiotic recipients (p=0.03), while empiric prescribing declined correspondingly. Overall antibiotic utilization remained high in both years (96.1% vs 95.2%; p=1.00), and meropenem use rose from 42.9% to 56.7% (p=0.13). AMS interventions were recommended in 67.6% and 63.5% of visits, respectively. Clinician acceptance improved markedly from 40.6% (95% CI: 29.8-52.4%) to 67.5% (95% CI: 52.0-79.9%) (p=0.01). Conclusions Two years of PAF in a Ghanaian quaternary ICU demonstrated progressive program maturation: universal biomarker adoption, a significant shift toward targeted prescribing, and markedly enhanced clinician acceptance. Persistently high antibiotic utilization and rising carbapenem dependence underscore the need for sustained surveillance and carbapenem-sparing strategies in LMIC critical care.

Background Severe Clostridioides difficile infection (CDI) morbidity and mortality disproportionately affect Black and Hispanic patients in the United States. Antibiotic exposure is the primary modifiable risk factor for CDI, and clindamycin is among the agents most strongly associated with related harm. Characterizing inequities in prescribing is critical. Dentistry is a major source of clindamycin prescriptions. Academic dental clinics serve diverse patient populations and provide an ideal setting to evaluate prescribing across racial and ethnic groups. We therefore examined antibiotic use and cumulative clindamycin exposure as measures of CDI-associated risk. Methods We conducted a retrospective study of electronic health records from 5 US academic dental institutions from 2021 through 2023. We analyzed 552,428 encounters among 132,770 patients with documented race/ethnicity to estimate adjusted odds of receiving any oral antibiotic and clindamycin by race/ethnicity. Secondary outcomes evaluated total antibiotic exposure among dental provider-prescribed antibiotics, focusing on higher-than-standard cumulative dosing of clindamycin (>8400 mg) and amoxicillin (>10,500 mg). Results Oral antibiotic prescribing occurred in 1.9% of encounters. Compared with White patients, Black, Hispanic, and Other race patients had slightly lower adjusted odds of receiving any oral antibiotic, while Black patients had greater odds of receiving a higher-than-standard cumulative clindamycin dose when clindamycin was prescribed (adjusted odds ratio, 2.19; 95% confidence interval, 1.25-3.82). Conclusion Racial and ethnic inequities in dental antibiotic prescribing extended beyond antibiotic receipt to cumulative clindamycin exposure. Although CDI outcomes were not directly measured, these prescribing differences may have implications for disparities in CDI-associated harm and warrant further investigation.

Background: Vancomycin-resistant Enterococcus (VRE) species are common healthcare-associated pathogens that cause difficult-to-treat infections. Whole genome sequencing of patients has revealed a substantial burden of patient-to-patient VRE transmission in hospitals, with patients in intensive care units (ICUs) at particularly high risk of acquisition. However, few studies adequately characterize the pathways of VRE transmission between patients in acute care settings, a necessary step to identify current gaps in infection prevention practices. By harnessing genomic clustering analyses of whole genome sequences of VRE isolates from patients, environmental surfaces, and healthcare providers (HCP) in ICUs, we aim to reconstruct indirect pathways of pathogen movement to identify patterns of VRE spread and opportunities for transmission prevention. Methods and Findings: We collected daily samples (N = 6848) from ICUs in two hospitals over 13 weeks from four main sampling sources: patients, HCP hands, patient rooms, and shared surfaces. Samples were cultured on selective media and sent for whole genome sequencing (WGS). We used genomic thresholds to identify clusters of related VRE isolates and distinguish unrelated isolates. VRE was detected in samples from 20 out of 322 unique occupant-stays (6.22%). VRE isolates were detected from all sampling sources except for shared surfaces. A total of 44 unique VRE isolates were identified, 43 Enterococcus faecium (VREfm) and one Enterococcus faecalis (VREf). Two distinct patterns of VREfm spread were observed: 1) an outbreak setting with observed patient-to-patient transmission and low VRE diversity, and 2) high VRE diversity and pathogen movement between occupant-stays facilitated by persistent HCP and environmental contamination, but no observed transmission events. VRE detection probabilities were not significantly different between occupant-stays in outbreak and non-outbreak settings (OR = 0.63, 95% CI (0.23, 1.83), p = 0.32). However, inclusion of VRE isolated from non-patient samples increased the number of occupant-stays with VRE detection from 6 to 20, a 3.3-fold increase, as compared to patient samples alone. Inclusion of non-patient samples also increased the number of VRE multi-isolate genomic clusters detected by 7-fold. Our findings are limited because sampling was primarily conducted in ICUs. Due to the combination of short ICU stay durations and imperfect test sensitivity, VRE transmission events were probably underdetected. Conclusions: Our findings characterize the complex nature of VRE transmission pathways in ICU settings. Even without an ongoing outbreak, we found substantial evidence of VRE movement between occupant-stays, facilitated by a combination of HCP hands and environmental surfaces. This study highlights the importance of environmental sampling for understanding VRE transmission potential, which is likely to be underestimated using patient sampling alone. We recommend that future studies incorporate follow-up sampling after discharge to better understand the true burden of transmission.

Background: Accurately identifying patients who will require opioids after third molar extraction could improve pain management while supporting opioid stewardship. This study evaluated surgeon accuracy in predicting supplemental opioid use following treatment with ibuprofen and acetaminophen. Methods: Patients (N=85) undergoing third molar extraction were treated with a standardized analgesic regimen of ibuprofen+acetaminophen, with supplemental opioid if needed. Four surgeons independently reviewed preoperative radiographs, assessed surgical difficulty using the Pederson scale, and rated the likelihood of supplemental opioid use on a 5-point Likert scale. Inter-rater reliability was assessed using intraclass correlation coefficients (ICC). The relationship between surgeon ratings and postoperative opioid use was evaluated using logistic regression and receiver operating characteristic (ROC) analysis. Results: Seventeen patients used supplemental opioid analgesics. Inter-rater reliability among surgeons was moderate (ICC3=0.606, 95%CI: 0.505-0.700), while reliability of the average rating across surgeons was good (ICC3k = 0.860, 95% CI: 0.804-0.903). Median surgeon rating was not associated with postoperative opioid use (OR: 0.800, 95% CI: 0.414-1.51, p=0.496) and demonstrated poor discrimination (AUC: 0.551, 95% CI: 0.392-0.710). Surgeon ratings were positively associated with Pederson score (beta=0.073, 95%CI: 0.050-0.096; p<0.001). Conclusions: Surgeons demonstrated moderate agreement, but these assessments did not accurately identify patients who ultimately required supplemental opioids. Surgeon judgments appeared to be influenced by anticipated surgical difficulty. Practical Implications: Clinicians should follow current recommendations against routine "just-in-case" opioid prescribing after third molar extraction. Future studies should focus on identifying clinical and biological predictors of inadequate analgesic response to NSAIDs to support individualized pain management strategies.

The global dissemination of antimicrobial resistance is increasingly driven by bacterial clones combining antimicrobial resistance with enhanced virulence and environmental adaptability. Escherichia coli sequence type 131 (ST131) has historically been regarded as a major disseminator of the extended-spectrum {beta}-lactamase (ESBL) blaCTX-M-15. However, the emergence of E. coli ST1193 carrying blaCTX-M-15 may represent an ongoing shift in the epidemiology of this resistance determinant. Here, we investigated the prevalence, genomic characteristics, virulence and antimicrobial resistance potential of ST1193 in comparison with ST131. A total of 1,136 E. coli isolates were recovered from touristic and non-touristic environments, hospital-associated samples, and aircraft toilets in Guadeloupe. Isolates were whole-genome sequenced and analysed for antimicrobial resistance and virulence determinants. Additionally, publicly available genomic data comprising 1,215 blaCTX-M-15-positive ST131 and ST1193 isolates were analysed to assess temporal and geographical trends. ST1193 was significantly associated with aircraft-associated samples and exhibited a higher antimicrobial resistance gene burden than ST131, while maintaining a comparable virulence factor content. Analysis of publicly available genomes revealed similar temporal emergence patterns for blaCTX-M-15-positive ST1193 and ST131, with ST1193 showing a more recent distribution and a higher number of deposited isolates in recent years, consistent with a potential ongoing clonal replacement. Comparative genomic analysis identified numerous virulence and adaptation-associated genes shared between both sequence types, while ST1193 additionally carried distinct determinants, including components of the transmissible locus of stress tolerance. Furthermore, quinolone resistance-associated mutations were strongly linked to blaCTX-M-15 carriage, particularly among ST1193 isolates. Together, these findings identify E. coli ST1193 as an emerging high-risk clone with substantial potential for blaCTX-M-15 dissemination. Its association with aircraft-associated samples further highlights the potential role of air travel in long-distance transmission and underscores the need to reconsider current surveillance strategies focused predominantly on ST131.

Antimicrobial resistance constitutes a major threat to global public health. Among emerging extensively drug-resistant bacteria (eXDR), carbapenemase-producing Enterobacteriaceae (CPE) expose hospitals to outbreaks through rapid dissemination, and to therapeutic limitations. Through a mixed epidemiological-qualitative methods study, we report the most extensive CPE carriage outbreak known to date in France, which occurred at Hopital Europeen Marseille (HEM) between January and June 2025. By the end of November 2024, the admission of an index patient returning from Senegal carrying an NDM-producing Escherichia coli led to an extensive transmission, despite adherence to national screen and isolate guidelines. More than 7,500 rectal screening tests evidenced 481 CPE carriers (including 343 NDM, 129 OXA-48-like and 9 other CPE), and 14 vancomycin-resistant Enterococcus faecium carriers. This major outbreak conducted to a phenomenal involvement of clinical, technical and administrative teams within the institution. It highlighted operational limitations in current screening, cohorting and biocleaning strategies in the context of hospital-wide outbreak. We describe the outbreak trajectory, the control measures implemented and provide a structured synthesis of lessons learned across organisational, scientific and policy domains.

Background: Healthcare has witnessed administrative staffing roles balloon to twice the number of employed clinicians, resulting in $950 billion per year in administrative costs to deliver healthcare. Administrative workflows, like fax routing, are ripe for automation given the high human labor cost necessary to complete these tasks. Facsimile transmissions remain a key mode of communication in modern healthcare, requiring substantial manpower, and incurring significant, though not well-characterized, costs to health systems. Opportunities may exist for agentic artificial intelligence (AI) to automate this administrative task. Methods: This quality improvement study was performed in 2 phases at Duke University's Division of Cardiology, a single tertiary-care cardiac referral center. The first retrospective phase employed an observational time study design surveying manual fax routing processes at 3 representative cardiology clinics from April 1, 2024, to July 12, 2024. The second phase quantified all inbound faxes received through the division's communication hub from July 1, 2025, to December 31, 2025, and applied direct labor costs observed in the time study to quantify the economic burden of manual fax routing across the hub. Results: The observational time study (Phase 1) demonstrated fax routing processing times ranging from 4.4 to 9.4 minutes depending on fax type, with a mean processing time of 6.0 minutes per fax. On average, the ambulatory clinics received 1,694 faxes per month and spent 169.1 person-hours routing faxes. The divisional communication hub (Phase 2) received 24,420 faxes over the study period, averaging 4,070 inbound faxes and 13,341 pages of information per month. Extrapolating direct labor efforts from the time study, 407 person-hours per month were spent processing inbound faxes. For our institution, this translated to $10,663.40 in total monthly costs, roughly 2.5 full-time equivalents. Conclusion: Manual fax routing represents a substantial, measurable, and previously under-characterized operational and administrative burden. Given the significant opportunity to reduce labor time and costs, our study establishes fax routing as a high-value target for automation. Future work is needed to determine the impact of AI-automated fax routing on the time, labor, accuracy, and economics within clinical settings.

Objectives: Dentists prescribe approximately one in ten antibiotics worldwide, yet antimicrobial stewardship (AMS) remains underemphasized in dental education. Large language models (LLMs) may support AMS training, but their proficiency and clinical reasoning in this context remain unclear. We evaluated GPT-4o's accuracy and clinical reasoning on dental antibiotic prescribing questions, stratified by question difficulty. Methods: We assembled 125 multiple-choice questions on dental antibiotic prescribing from eight peer-reviewed studies (2017-2023). GPT-4o answered each question and generated a clinical justification. Accuracy was assessed against source-study answer keys and examined across difficulty quartiles. Justifications were evaluated using an adapted 12-axis human-evaluation framework assessing scientific consensus, extent and likelihood of harm, inappropriate and missing content, bias, and both correct and incorrect comprehension, retrieval, and reasoning. Prophylaxis-specific questions were analysed separately. Results: GPT-4o correctly answered 72% of questions. Accuracy remained relatively stable across difficulty quartiles (78%, 78%, 65%, 70%). Experts rated 95.4% of justifications positively across the 12 axes. Comprehension, retrieval, and reasoning each exceeded 96.2% positive ratings. Missing content was the main weakness (7.8%), and 7.1% of justifications showed a moderate-to-severe potential for harm. Performance on prophylaxis-specific questions (98.1%) exceeded non-prophylaxis questions (93.0%). Conclusions: GPT-4o demonstrated moderate-to-high proficiency and clinically defensible reasoning in dental antibiotic prescribing questions. However, residual risks indicate that it is not suitable for unsupervised clinical use but shows potential as a supervised AMS educational tool.

This study aimed to clarify aerosol exposure risks throughout the workflow of a Biosafety Level 2 (BSL-2) polymerase chain reaction (PCR) laboratory, validate the suitability of the {Phi}X174 bacteriophage as an indicator virus, and provide evidence for biosafety control measures. The {Phi}X174 bacteriophage was used to simulate viral samples, and a concentration-bacteriophage plaque standard curve was constructed (R2=0.998). Five operational steps in a simulated PCR laboratory were quantitatively monitored for aerosol concentration using double-layer agar plates, with blank controls used to eliminate interference. Statistical analysis was employed to identify risk differences. Sample homogenization ((5.67 {+/-} 1.23) x 104 plaque-forming units (PFU)/m3) and nucleic acid extraction ((3.45 {+/-} 0.89) x 104 PFU/m3) were identified as high-/very high-risk steps. The viral load in the samples was strongly positively correlated with the aerosol concentration (r = 0.926, P <0.001), with aerosol levels linearly decreasing with increasing distance in high-risk steps. The {Phi}X174 bacteriophage demonstrated high detection sensitivity (101 PFU/ml) and demonstrated safety compatibility with BSL-2 laboratories. Aerosol risks in PCR laboratories exhibit step-specific differentiation, and {Phi}X174 serves as an ideal indicator virus. Proposed strategies such as equipment upgrades and personal protective equipment (PPE) grading can reduce exposure risks.

Introduction Anatomical endoscopic enucleation of the prostate (AEEP) techniques, including bipolar enucleation (B-TUEP), holmium laser enucleation (HoLEP), thulium laser enucleation (ThuLEP), and thulium fibre laser enucleation (ThuFLEP), demonstrate comparable clinical outcomes for benign prostatic hyperplasia. As clinical equivalence is increasingly established, cost becomes a key determinant of modality selection. We performed a cost minimisation analysis comparing index procedural costs across AEEP modalities from an institutional perspective. Methods A cost minimisation model was developed from the institutional perspective, incorporating amortised capital costs, maintenance, and consumables. In addition to the base-case scenario of 180 cases per year, we modelled two additional case volume scenarios: low (50 cases/year) and high (500 cases/year) volume. Thu:YAG laser fibres were modelled on two scenarios: disposable single-use, and reusable fibres (up to 10 cases per fibre). Breakeven analysis determined the threshold volume at which each laser modality achieves cost parity with B-TUEP, and one-way sensitivity analysis was performed on key cost parameters. Analysis was limited to index procedural costs calculated in Singapore dollars. Results At the base case of 180 cases per year, B-TUEP had the lowest index procedure cost (SGD 1,018), followed by ThuFLEP (SGD 1,584), ThuLEP (1,599), and HoLEP (SGD 1,655). Breakeven analysis demonstrated that HoLEP, ThuLEP, and ThuFLEP can never achieve cost parity with B-TUEP when laser fibres are single-use, as laser modalities carry higher costs on both capital and per-case dimensions. ThuLEP with reusable fibres (10 uses per fibre) was the only modality to cross below B-TUEP, at a breakeven volume of 198 cases per year. At 500 cases per year with reusable fibres, ThuLEP achieved the lowest cost (SGD 847), representing a 15.4% saving over B-TUEP. Sensitivity analysis identified annual case volume and B-TUEP loop cost as the most influential parameters. Conclusion Index procedural costs in AEEP are strongly influenced by case volume and consumable strategy. While B-TUEP remains cost-efficient at low volume, high-volume practice combined with reusable Thu:YAG fibre technology enables cost parity and potential cost advantage for laser enucleation. These findings highlight the importance of economies of scale and device utilisation in technology adoption.

Background: Cone-beam computed tomography (CBCT) frequently captures the maxillary sinuses incidentally, and reliable automated detection of sinus abnormality is clinically relevant. Unlike most vision-language benchmarks in medical imaging, which pair images with pre-existing, human-authored clinical reports, findings text can also be generated directly by a large language model from the image itself--raising the question of how much diagnostic value such AI-derived text carries, and whether that value depends on independent verification. Multimodal artificial intelligence (AI) benchmarks risk overstating performance if the provenance of each input--image, raw AI-generated text, or radiologist-verified text--is not clearly separated and reported. Methods: We used 300 mid-sagittal CBCT slices from the MMDental dataset. ChatGPT generated findings text and a provisional normal/abnormal label for every slice (majority vote, three independent readings from the image alone); primary classification performance was assessed on this full, unfiltered set (n=300). A radiologist then independently reviewed each case's image together with ChatGPT's description, producing their own diagnosis; three cases were excluded as insufficient, yielding 297 confirmed cases. On this subset, every model was retrained and re-evaluated under identical 10-fold cross-validation on both the provisional ChatGPT-only labels ("pre") and the radiologist-confirmed labels ("post"), isolating the effect of label provenance from image or architecture. Eight vision architectures, seven language classifiers, and five VLMs were evaluated throughout; three generative models performed exploratory note-drafting. Findings: Raw ChatGPT-generated text produced the highest performance of any modality or condition: language models reached near-ceiling AUC (0.992 to 1.000, n=300), exceeding every vision model (AUC 0.799 to 0.880) and every VLM image-only probe (AUC 0.63 to 0.69). On the 297-case pre/post analysis, this advantage depended heavily on label source: language and text-derived VLM performance fell substantially from ChatGPT-only to radiologist-confirmed labels (e.g. BERT-base AUC 0.999 to 0.837), while vision-model performance was stable or modestly improved (e.g. DenseNet-121 0.867 to 0.891). The radiologist reclassified 62 of 297 cases (21%) relative to ChatGPT's provisional read, and a meaningful proportion of raw ChatGPT text was clinically uninterpretable or unsupported by the imaging. Interpretation: As shown here for the first time, raw, image-derived AI-generated text yields the highest apparent classification performance in this benchmark, but this reflects the text's alignment with its own self-generated labels rather than verified diagnostic content, and a substantial share of that text is not clinically explainable. Radiologist-confirmed text and labels give a lower but trustworthy estimate of true performance, on which convolutional neural network (CNN) vision models remain a stable, comparatively inexpensive baseline. Multimodal dental AI should report performance separately by modality and label provenance rather than pooling headline metrics.

Background: Carbapenemase producing Enterobacterales (CPE) remain a major infection prevention and control challenge. Although care home residence is frequently perceived as a risk factor for CPE carriage, its independent association with CPE positivity remains uncertain. Objective: To investigate the relationship between care home residence on admission and CPE positivity among patients undergoing CPE screening. Methods: A retrospective matched case control study was conducted at a single NHS acute hospital in England. Adult patients with laboratory confirmed CPE positivity from screening samples between 1 November 2022 and 1 November 2025 were matched to CPE negative controls at a ratio of up to 1:4 based on ward, specimen year and age no more than 5 years older or younger. Conditional logistic regression was used to assess the association between care home residence and CPE positivity. An adjusted model included previous hospital admission within 12 months. Results: A total of 108 CPE positive cases were successfully matched to 412 controls. Care home residence was identified in 14 (13.0%) cases and 49 (11.9%) controls. In the matched conditional logistic regression model, care home residence was not associated with CPE positivity (OR 1.15, 95% CI 0.58 to 2.28; p=0.690) and remained non-significant after adjustment (aOR 1.32, 95% CI 0.66 to 2.64; p=0.439). Discussion: Care home residence was not independently associated with CPE positivity in this low-prevalence setting. Significance and impact: The findings do not support the use of care home residence alone to guide CPE screening. Further multicentre studies are required to clarify the contribution of care home residence to CPE epidemiology.

BACKGROUND: Nontuberculous mycobacteria (NTM) are environmental organisms increasingly causing chronic respiratory infection. Although NTM pulmonary infection is rising globally, most studies are single-country. This study evaluated temporal trends in pulmonary NTM incidence across Queensland (Australia), Phnom Penh (Cambodia), Japan, Thailand, and the United States (US), and described regional species distribution. METHODS: Laboratory and insurance claims data were used. Incident infections were defined using region-specific criteria. For Queensland, Japan, and Thailand, data and denominators covered entire regions. US estimates included Medicare beneficiaries aged [&ge;]65 years, and Cambodian incidence was estimated from Phnom Penh data and standardised nationally. Incidence rates per 100,000 population and incidence rate ratios (IRRs) were calculated overall and by sex. Age-stratified analyses and species distributions were summarised where data were available. RESULTS: Pulmonary NTM incidence increased in all regions and was highest in Japan (47.20-57.40 per 100,000) and lowest in Phnom Penh (0.23-0.38). Queensland showed the largest increase over 24 years (IRR 7.06, p<0.0001). Female predominance occurred in high-income regions, whereas Thailand showed ~1.5-fold male predominance and Phnom Penh showed no sex predominance. Incidence was higher among individuals aged [&ge;]60 years. Mycobacterium avium complex predominated in Japan and Queensland, and M. abscessus in Thailand and Phnom Penh. CONCLUSIONS: Pulmonary NTM incidence increased in all regions, varying by demographic patterns and species distribution. Differences largely reflect under-ascertainment related to diagnostic capacity and tuberculosis-focused health systems rather than true infection burden. Strengthened surveillance and diagnostic capacity are needed to define the global burden of NTM pulmonary infection.

Background: The main cause of urinary tract infections (UTIs) are Gram negative bacteria with Escherichia coli as the leading cause and other important pathogens such as Klebsiella pneumoniae, Pseudomonas aeuriginosa and Enterococcus faecalis. Over the years uropathogens have become resistant to commonly used antibiotics, including penicillin's, cephalosporins and fluoroquinolones. Antimicrobial resistance (AMR) in UTIs is mainly caused by the misuse and overuse of antibiotics, recurrent infections, and healthcare-associated factors such as catheterization. Objectives: The aim of this study was to describe the bacteriological profile and antimicrobial susceptibility patterns of uropathogens isolated from positive urine cultures at Chhatrapati Shivaji Subharti Hospital, Meerut, a tertiary care centre in North India and develop an institutional antibiogram to support empirical prescribing and antibiotic stewardship at this institution. Materials & Methods: The study analysed 50 positive urine culture samples and their antimicrobial susceptibility records from July 2025 to December 2025. The isolates were identified, and antimicrobial susceptibility testing was performed using the disc diffusion method and automated Biomerieux Vitek 2 Compact machine. The collected data was analysed using descriptive statistics and Fisher's exact test. Results: Gram-negative bacteria accounted for 80.0% (40/50) of the culture-positive urine isolates. Escherichia coli was the most frequently isolated uropathogen (n=23, 46.0%), followed by Klebsiella pneumoniae (n=12, 24.0%), Candida spp. (n=6, 12.0%), Enterococcus spp. (n=4,8.0%), Pseudomonas aeruginosa (n=3, 6.0%), and Enterobacter cloacae (n=2, 4.0%). Of the total, 74% (37/50) of isolates came from Inpatient samples. E. coli had a 100% resistance to ampicillin and ceftriaxone, 95.7% to ciprofloxacin and cefepime, and 73.9% to meropenem, with fosfomycin (86.4% sensitive) and colistin (69.6% sensitive) as the only effective antimicrobials. K. pneumoniae had 100% resistance to ceftriaxone, amoxicillin-clavulanate, and piperacillintazobactam; carbapenem resistance ranged from 83.3% to 91.7%, and colistin was the only consistently effective treatment (83.3% sensitive). Of all the 35 tested Enterobacteriaceae isolates, Extended-Spectrum Beta-Lactamases (ESBLs) positivity was 100% with Carbapenem-Resistant Enterobacterales (CRE) positivity at 85.0%. All the bacterial isolates met Multi-drug Resistant (MDR) criteria. 31 of 35 (88.6%) tested Enterobacteriaceae isolates showed ESBL and CRE copositivity. The six strains of Candida demonstrated total sensitivity to all the antifungal drugs used. Conclusion: There is a critical burden of AMR at this hospital with 100% ESBL positivity, 85% CRE, and 100% MDR among all bacterial isolates. This study provides the first baseline institutional antibiogram to guide empirical prescribing and antibiotic stewardship at Chhatrapati Subharti Hospital.

Objective. A deep learning (DL) model was used to convert smartphone videos of a complete arch implant cast into 3D scans. The aim of current study was to determine if a custom scan body (SB) with geometric features and coating would outperform regular PEEK stock SB in this DL scenario. The DL-derived scan outcomes were compared with those obtained from a conventional splinted open-tray impression and from photogrammetry. Materials and Methods. A maxillary edentulous model with six implants and multi-unit abutment analogs was scanned using four protocols: conventional splinted open-tray impression (CO), photogrammetry (PG; Icam4D), DL using stock SBs (DLS) and DL using custom SBs (DLC). Each protocol was repeated for 10 times. The DL scans were produced from smartphone videos with a high-fidelity, multi-view 3D construction AI model (Neuralangelo). The custom designed SB incorporated geometric features and was fabricated via 3D printing followed by a spray coating. Accuracy (trueness and precision) was assessed using three measurements: Root Mean Square (RMS), linear deviation, and angular deviation. Results. DLC outperformed DLS in both trueness and precision regarding RMS and linear measurements (p<0.001). CO and PG demonstrated the highest RMS and linear trueness, with no significant difference between them (RMS: p=0.93; linear: p=0.663). PG achieved the best precision across RMS, linear and angular measurements. Conclusion. The optimised SB significantly improves the accuracy of DL-based approach for full-arch implant scan comparing to regular PEEK stock scan bodies. While early stage, neural surface reconstruction has potential as a viable option for full-arch implant rehabilitation.

Background: Autonomous ultraviolet-C (UV-C) disinfection systems are increasingly used to supplement manual environmental cleaning, yet evidence-based guidance defining pathogen-specific UV-C dose requirements across representative surfaces remains limited. Aim: To characterize operational UV-C dose requirements for clinically relevant pathogens across diverse high-touch and healthcare surfaces and determine how experimentally derived microbial inactivation can inform operational exposure parameters. Methods: SARS-CoV-2, adenovirus, Pseudomonas aeruginosa, Staphylococcus aureus, Klebsiella pneumoniae, Enterococcus faecalis, Candida auris, and Clostridioides difficile spores were exposed to defined UV-C doses on representative high-touch materials or stainless steel under standardized conditions, including a 10% fetal bovine serum organic soil challenge. Microbial inactivation was quantified by viable recovery. Dose-response analysis and operational modelling were used where supported by the experimental data. Findings: UV-C exposure significantly reduced viable recovery of all pathogens, with substantial differences in the exposure conditions associated with microbial inactivation. SARS-CoV-2 exhibited substantial inactivation at doses as low as 2.6 mJ/cm2, whereas the highest evaluated doses were 1,800 mJ/cm2 for C. difficile spores and 3600 mJ/cm2 for C. auris. For C. auris, multi-dose data estimated that approximately 1,410 mJ/cm2 was associated with a 2-log10 reference reduction, enabling distance-dependent exposure-time predictions. Conclusion: Experimentally quantified UV-C exposures produced substantial microbial inactivation across diverse pathogen classes and surfaces. Integrating delivered dose with microbial reduction provides a quantitative framework for translating laboratory efficacy into operational parameters for autonomous UV-C disinfection.

Advances in air-based surveillance of pathogen genetic material are hindered by reliance on centralized, time-consuming molecular techniques. Point-of-care (POC) diagnostic platforms, like the Cepheid(R) GeneXpert(R), offer rapid, simplified testing in clinical settings but have not been evaluated for use with air samples. Here, we paired the ThermoFisherTM AerosolSenseTM air sampler with the Xpert(R) Xpress SARS-CoV-2/Flu/RSV Plus test to evaluate near-real-time air surveillance. To assess analytical sensitivity, we spiked collection substrates with inactivated viruses and performed overnight sampling using the air sampler. As few as 10 copies of influenza A/B (IAV/IBV) and RSV applied to the substrate were detectable by GeneXpert, while SARS-CoV-2 required at least 100 copies for detection. Longitudinal air surveillance was conducted across congregate settings in Columbia, Missouri, and Madison, Wisconsin, in 2024-2025, collecting 281 air samples. SARS-CoV-2 was detected most frequently, followed by IAV. To assess concordance, 191 samples with paired GeneXpert and RT-qPCR results were analyzed across multiple Ct value cutoffs. Agreement between GeneXpert and RT-qPCR for SARS-CoV-2 was fair to moderate (K = 0.306-0.443). Optimal GeneXpert Ct cutoffs for the best balance between sensitivity and specificity, determined using analyses such as Youden's index, were site-specific: 45 for Wisconsin (67% sensitivity, 83% specificity) and 41 for Missouri (76% sensitivity, 62% specificity), reflecting differences in laboratory protocols. For IAV, agreement was moderate (K = 0.56) with GeneXpert Ct cutoff of 40, achieving 85% sensitivity and 81% specificity. Further studies across diverse settings and viral targets are needed to establish GeneXpert's role in routine air surveillance.

Blood banks represent highly controlled healthcare environments where microbiological surveillance has traditionally focused on blood products rather than environmental microbial reservoirs. Despite their critical role in transfusion safety, the ecology of surface-associated microorganisms and the persistence traits that enable their long-term survival remain poorly understood. Here, we combined scanning electron microscopy, culture-based microbiology, phenotypic characterization, MALDI-TOF mass spectrometry, and whole-genome sequencing to investigate whether surfaces within a public blood bank facility constitute reservoirs of environmentally derived bacteria with enhanced persistence potential. Samples collected from a public blood bank in Tucuman, Argentina yielded 37 culturable bacterial isolates, predominantly Gram-positive environmental taxa together with a limited number of opportunistic Gram-negative species. More than 30% of the isolates exhibited multidrug resistance, while several strains displayed strong biofilm formation, amyloid-like fiber production, motility, and hemolytic activity, indicating multiple phenotypic strategies associated with long-term surface persistence. Whole-genome sequencing of six representative isolates confirmed species identity, identified genes related to antimicrobial resistance, adhesion, biofilm formation, stress adaptation, and cytotoxicity, and revealed frequent genotype-phenotype discordance, highlighting the importance of integrating genomic and phenotypic analyses. Notably, one isolate exhibited less than 92% average nucleotide identity with publicly available genomes, suggesting the presence of a previously undescribed environmental species. Thus, blood bank surfaces function as selective ecological niches favoring bacteria with persistence-associated traits rather than simply reflecting contamination from blood products. These microorganisms may constitute latent biosafety hazards if environmental barriers fail, particularly in facilities handling biological materials intended for vulnerable patients. Our results support the incorporation of integrated bioimaging, phenotypic characterization, and genome-resolved environmental surveillance into infection prevention strategies and transfusion biosafety programs within a One Health framework.

Background Using a population-based cohort from the Calgary Health Zone (CHZ), Canada, we integrated longitudinal antimicrobial susceptibility and prescribing data with the whole genome sequences of five major pathogens. We aimed to assess how antimicrobial resistance (AMR) responds to prescribing changes and determine which bacterial strains shape these dynamics. Methods We analysed antibiotic prescribing rates, clinical and genomic data from 7,271 Staphylococcus aureus, 1,609 Enterococcus faecalis, 801 Enterococcus faecium, 11,363 Escherichia coli, and 2,319 Klebsiella pneumoniae isolates, associated with bacteraemia episodes in the CHZ between 2006-2022. Genomic clusters (referred to as strains) were identified using StrainGST and assigned to known sequence types (STs) or clonal complexes (CCs). Strain-level incidence, stratified by community-onset (isolates collected [&le;]48h after admission) and hospital-onset (>48h after admission), AMR phenotypes, and prescribing rates were modelled using negative-binomial and binomial regression. Temporal trends were quantified using average annual percentage change (AAPC). Findings Between 2010-2022, fluoroquinolone prescribing declined in both community (AAPC=-6.8% [95% CI -8.1, -5.4]; p<0.0001) and hospital settings (AAPC=-5.1% [-6.5, -3.7]; p<0.0001). This was accompanied by a significant reduction in fluoroquinolone resistance among Gram-positive species. Specifically, S aureus bacteraemia resistant to clinically important antibiotics, cloxacillin, ciprofloxacin, erythromycin, and clindamycin, declined from 2006 to 2022, mostly in hospital-onset cases (AAPC=-16.0%, [-19.3%, -12.7%], p<0.0001). In E coli, ceftriaxone and ciprofloxacin resistance were clustered in ST131 and the emerging ST1193; the latter increased steadily, particularly in community-onset cases (AAPC=17.7%, [0.0%, 30.0%], p<0.0001). CTX-M-27-producing E coli ST131 strains increased (AAPC=23.8%, [17.4%, 30.5%], p<0.0001) between 20082022, while CTX-M-14-producing E coli ST131 declined (AAPC=-15.9%, [-21.3%, -10.2%], p<0.0001) between 2013-2022. These trends were paralleled by an increase in community cephalosporin prescribing (AAPC=7.3%, [4.2%, 10.5%], p<0.0001) between 2010-2022. For K pneumoniae, hypervirulent ST23 was most common (N=88) with an increasing trend in incidence (AAPC=3.0%, [-2.8%, 9.2%]) between 2006-2019. Conclusions The contrasting resistance trends between Gram-positive and Gram-negative species underscore the complexity of AMR control efforts. Effective strategies will require stewardship efforts targeting multiple drug classes, genomic surveillance for emerging resistant strains, and interventions extending beyond hospital settings.

Objectives: To investigate whether ethambutol resistance in Mycobacterium avium complex is associated with the emergence of macrolide resistance. Methods: Patients who developed macrolide resistance during guideline-based treatment were included, and longitudinal analyses of minimum inhibitory concentrations and mutations in embB or the upstream region of embA were performed. Clinical, microbiological, and radiological characteristics were compared according to the mutation status of embB or embA upstream region, prior to the emergence of macrolide resistance. We further evaluated the impact of embB mutation on the development of macrolide resistance using in vitro time-kill assays. Results: Sixteen patients developed macrolide resistance during guideline-based treatment. None of these patients had an ethambutol minimum inhibitory concentration >=16 ug/mL or embB or embA upstream mutations at treatment initiation; however, 8/16 patients (50.0%) had an ethambutol minimum inhibitory concentration >=16 ug/mL at the time of macrolide resistance detection, and 7/16 (43.8%) had developed embB or embA upstream mutations prior to the emergence of macrolide resistance. Cavitary lesions were present in 1/7 (14.3%) patients with embB or embA upstream mutations. In strains with embB mutations, the minimum inhibitory concentration of ethambutol increased by 1-2 dilutions relative to that of pretreatment isolates, with a corresponding increase in the concentration required to suppress macrolide resistance. Conclusions: Ethambutol resistance may contribute to the development of macrolide resistance in patients with M. avium complex pulmonary disease, particularly in those without cavitary lesions.