Early Warning Approach to Identify Positive Cases of SARS-CoV-2 in School Settings in Italy.

During the COVID-19 pandemic, some studies suggested that transmission events could originate from schools. This study aimed to evaluate early-warning methods for identifying asymptomatic COVID-19 cases by implementing screening programs in schools. This study was conducted between September 2021 and May 2023, employing a rotation-screening plan for COVID-19 detection on a sample of students aged 14 to 19 years attending secondary schools in the regions of Tuscany, Veneto, Apulia and Friuli-Venezia Giulia.

Molecular Assays on Cutaneous Swabs as an Effective, Non-Invasive Diagnostic Technique for Cutaneous Leishmaniasis: Results from a Retrospective Study Conducted in Italy.

Background: The case confirmation of CL relies on the direct demonstration of the parasite in clinical specimens from skin tissues. Despite most research efforts focusing on biopsy samples as the preferred diagnostic specimen for the detection of spp., the use of non-invasive sampling, such as cutaneous swabs, combined with the use of molecular assays, has shown promising results.

Detection of β-lactam resistance genes in Gram-negative bacteria from positive blood cultures using a microchip-based molecular assay.

Background: Accurate detection of β-lactam resistance genes in bloodstream infections is critical for guiding antimicrobial therapy. This study evaluates the Alifax Gram-negative resistance (GNR) microchip assay for detecting β-lactam resistance genes directly from positive blood cultures (PBCs) for Gram-negative (GN) bacteria, including Enterobacterales, , and .

Methods: Simulated (n=146) and clinical (n=106) GN-PBC samples were tested for , , , , -like, -like, -ESBL, group, and -like genes using the GNR microchip assay.

Evaluation of QuickMIC system for rapid antimicrobial susceptibility testing of Gram-negative pathogens from positive blood cultures, including strains producing extended-spectrum β-lactamases and carbapenemases.

The accuracy and turnaround time (TAT) of the QuickMIC system (QMIC) for rapid antimicrobial susceptibility testing (AST) of Gram-negative pathogens from positive blood cultures were evaluated, in comparison with a standard-of-care workflow based on culture and AST with broth microdilution. Essential agreement (EA) and bias were evaluated according to the ISO 20776-2:2021, category agreement (CA), categorical overestimation (CO), and underestimation (CU) rates were evaluated according to the European Committee on Antimicrobial Susceptibility Testing(EUCAST) breakpoints, and major discrepancy (MD) and very major discrepancy (VMD) rates were evaluated according to the Food and Drug Administration (FDA) guidelines and breakpoints. QMIC yielded evaluable data for 103/118 blood cultures (87.

Next-generation diagnostics of bloodstream infections enabled by rapid whole-genome sequencing of bacterial cells purified from blood cultures.

Background: Blood culture (BC) remains the cornerstone for diagnosis of bloodstream infections (BSI), but the long turn-around time (TAT) hampers timely selection of appropriate chemotherapy. Novel molecular approaches have been developed to provide faster results but are also affected by limitations. We developed a analytical workflow named LC-WGS (Whole-Genome Sequencing of Liquid Colony) for rapid whole-genome sequencing-based diagnosis of BSI, evaluating its accuracy performance over standard of care (SoC) diagnostic procedures.

Evaluation of Xpert Carba-R Assay Performance from FecalSwab™ Samples.

: The emergence and spread of carbapenemase-producing (CPE) represents a significant challenge prompting the need to optimize diagnostic tools to detect CPE carriers. The Xpert Carba-R assay (Cepheid, Sunnyvale, CA, USA), a Real-Time PCR-based test, can detect the , , , and carbapenemase genes directly from rectal swabs. This study assessed the performance of the Xpert Carba-R assay using FecalSwab™ (Copan, Brescia, Italy), a liquid-based collection device.

Dealing with Challenges Posed by Antimicrobial Resistance in Long-Term Acute-Care Rehabilitation Facilities.

Antimicrobial resistance (AMR) has emerged as one of the major challenges for human health, with a remarkable burden of mortality, morbidity, and healthcare-associated costs [...

[The CCM Project "Phenotypic and molecular screening methodologies for the detection of coloniza-tions due to carbapenem-resistant Enterobacterales (CRE)"].

Carbapenem-resistant Enterobacterales (CREs) are globally considered to be a major threat to public health. National and international guidelines emphasize the importance of routine active surveillance policies to prevent their transmission. Consequently, screening for the evaluation of the status of colonization by CREs in hospitalized patients in Italy is considered essential to contain and control the spread of these microorganisms and their evolution towards infection.

Verifying the feasibility of wastewater-based epidemiological monitoring for the small catchment and sewage networks with significant pretreatment.

Wastewater-based epidemiology (WBE) has emerged as a valuable tool for COVID-19 monitoring, especially as the frequency of clinical testing diminishes. Beyond COronaVIrus Disease 19 (COVID-19), the tool's versatility extends to addressing various public health concerns, including antibiotic resistance and drug consumption. However, the complexity of sewage systems introduces noise when measuring chemical tracer concentrations, potentially compromising their applicability for modeling.

Evaluation of the Vitek® Reveal™ system for rapid antimicrobial susceptibility testing of Gram-negative pathogens, including ESBL, CRE and CRAB, from positive blood cultures.

Blood culture (BC) remains the reference diagnostic tool for bloodstream infections but is hampered by long turn-around time (TAT). This study evaluated the Vitek® Reveal™ (VR) system for rapid antimicrobial susceptibility testing (AST) with 72 cases of monomicrobial BCs (55 Enterobacterales, 12 Pseudomonas aeruginosa and 5 Acinetobacter baumannii), including isolates producing carbapenemases and/or extended-spectrum β-lactamases. VR returned AST results with a mean TAT of 5.

Evaluation of STANDARD™ M10 SARS-CoV-2 from bronchoalveolar lavage samples.

Detection of SARS-CoV-2 in bronchoalveolar lavage (BAL) is considered as a promising alternative method to detect COVID-19 infection. STANDARD™ M10 SARS-CoV-2 assay on 150 negative and 50 positives BAL samples for SARS-CoV-2 showed 96 % sensitivity, 100 % specificity compared to Allplex™ SARS-CoV-2 assay and a 31.25 genomic copies/mL limit of detection.

Evaluation of Quantamatrix dRAST system for rapid antimicrobial susceptibility testing of bacterial isolates from positive blood cultures, in comparison with commercial Micronaut broth microdilution system.

Antimicrobial susceptibility testing (AST) from blood culture (BC) may take several days, limiting the eventual impact on antimicrobial stewardship. Hence, rapid AST systems represent a valuable support in shorting the time-to-response. In this work, the Quantamatrix dRAST system (dRAST) was evaluated for rapid AST on 100 monomicrobial BCs (50 Gram-negatives and 50 Gram-positives), including several isolates with clinically relevant resistance mechanisms.

producing FIM-1-metallo-β-lactamase: emergence and cross-transmission in a long-term acute care rehabilitation hospital.

FIM-1 metallo-β-lactamase was previously detected in sporadic clinical isolates. Here, we report on FIM-1-positive from two patients who had shared the same ward in a long-term acute care rehabilitation hospital. Whole-genome sequencing analysis revealed close relatedness of these isolates, which belonged to an ST235 sublineage (clade 8/14) different from those previously reported.

Evaluation of different molecular systems for detection and quantification of SARS-CoV-2 RNA from wastewater samples.

Wastewater-based epidemiology has proved to be a suitable approach for tracking the spread of epidemic agents including SARS-CoV-2 RNA. Different protocols have been developed for quantitative detection of SARS-CoV-2 RNA from wastewater samples, but little is known on their performance. In this study we compared three protocols based on Reverse Transcription Real Time-PCR (RT-PCR) and one based on Droplet Digital PCR (ddPCR) for SARS-CoV-2 RNA detection from 35 wastewater samples.

Evaluation of two commercial broth microdilution systems for dalbavancin susceptibility testing of methicillin-resistant Staphylococcus aureus and other resistant Gram-positive cocci.

Objectives: This study aims to evaluate two commercial broth microdilution (BMD) systems, E1-185-100 (Merlin) and FDANDPF (ThermoFisher), for dalbavancin susceptibility testing in comparison with reference BMD assay.

Methods: Study collection was composed of 200 non-replicate multidrug-resistant Gram-positive cocci of clinical origin, including 180 methicillin-resistant Staphylococcus aureus, 10 vancomycin-resistant enterococci, seven linezolid-resistant Staphylococcus epidermidis, and three methicillin-resistant coagulase-negative staphylococci. S.

Novel resistance ICEs carrying the metallo-β-lactamase gene from an ST235 sublineage.

FIM-1 is an acquired metallo-β-lactamase identified in a multidrug-resistant (index strain FI-14/157) of clinical origin isolated in 2007 in Florence, Italy. Here we report on a second case of infection by FIM-1-positive (FI-17645), which occurred in 2020 in the same hospital. Both FIM-1-positive strains exhibited resistance to all anti- antibiotics except colistin and cefiderocol.

Evaluation of the Liquid Colony™ Produced by the FAST System for Shortening the Time of Bacterial Identification and Phenotypic Antimicrobial Susceptibility Testing and Detection of Resistance Mechanisms from Positive Blood Cultures.

Background: the aim of this study was to evaluate the performance of the Liquid Colony™ (LC) generated directly from positive blood cultures (PBCs) by the FAST System (Qvella, Richmond Hill, ON, Canada) for rapid identification (ID) and antimicrobial susceptibility testing (AST) compared with the standard of care (SOC) workflow.

Methods: Anonymized PBCs were processed in parallel by the FAST System and FAST PBC Prep cartridge (35 min runtime) and SOC. ID was performed by MALDI-ToF mass spectrometry (Bruker, Billerica, MA, USA).

Performance evaluation of the UMIC® Cefiderocol to determine MIC in Gram-negative bacteria.

Background: Cefiderocol is a catechol-substituted cephalosporin with potent in vitro activity against carbapenem-resistant (CR) Gram-negative bacteria (GNB). Cefiderocol susceptibility testing is complex because iron concentrations need to be taken into consideration. Here, we assessed the clinical performance of Bruker's UMIC® Cefiderocol and corresponding iron-depleted CAMHB to determine MIC by broth microdilution (BMD) for clinically relevant GNB.