Immunochromatographic Assay Research Articles

Exploring New Delhi Metallo Beta Lactamases in Klebsiella pneumoniae and Escherichia coli: genotypic vs. phenotypic insights

BackgroundCarbapenemase-producing Enterobacterales pose a serious clinical threat, particularly in high-burden settings of carbapenem-resistant Escherichia coli and Klebsiella pneumoniae (CREK), where rapid detection tools are essential to aid patient management. In this study, we focused on blaNDM, the most frequently reported carbapenemase in the region, and evaluated a combined phenotypic (lateral flow) and genotypic (PCR and WGS) approach for its detection. This research underscores the utility of lateral flow assays as a practical alternative to resource-intensive genotypic methods, offering a scalable solution for settings with limited laboratory capacity.MethodOne hundred seventy-seven extensively drug-resistant strains were characterized using MALDI-TOF. Isolates were analyzed to detect Carbapenem-resistant Escherichia coli and Klebsiella pneumoniae (CREK) using disk diffusion, MIC test, and PCR targeting blaNDM. Antibiotic susceptibility patterns were analyzed and visualized using single-linkage hierarchical clustering, with results displayed on a permuted heat map. Immunochromatographic assay, RESIST-5 O.K.N.V.I (Coris Bioconcept®) was used for CREK isolates [(n = 17), positive and negative)] and Oxford Nanopore Sequencing was conducted on subsets [(n = 5) blaNDM-positive co-producers of blaNDM and blaOXA, and (n = 2) blaNDM-negative blaOXA producers) to evaluate the reliability of phenotypic and genotypic tests.ResultMost of the XDR strains (90%) were CREK, with K. pneumoniae (71.2%) more prevalent than E. coli (28.7%) (p < 0.05). All CREK strains exhibited complete resistance (100%) to multiple antibiotics with 66% showing sensitivity to levofloxacin. Furthermore, K. pneumoniae (57.8%) had higher blaNDM gene prevalence than E. coli (36.9%). Among blaNDM-positive CREK, lateral flow assay revealed approximately half of each bacteria type co-produced blaOXA (E.coli, 52.9%), and (K. pneumoniae, 47%). For blaNDM-negative strains, blaOXA was more prevalent in K. pneumoniae (82.35%) than E. coli (41%) (p < 0.05). Comparing phenotypic to genotypic assays, E. coli showed 100% (CI 80.49 − 100%) sensitivity and specificity with a high Kappa agreement coefficient (0.91) (CI 95% 0.661–1, p < 0.01), whereas K. pneumoniae assays had lower sensitivity and specificity (40%) (CI 5.27 − 85.34%), with a lower Kappa agreement coefficient (0.20) (CI 95% 0.104–0.298, p < 0.01).ConclusionThis study demonstrates the value of the RESIST-5 O.K.N.V.I. lateral flow assay as a rapid and reliable diagnostic tool for detecting blaNDM in Escherichia coli, with strong agreement to PCR and WGS. While performance for Klebsiella pneumoniae was lower, the assay offers a practical alternative in resource-limited settings, aiding antimicrobial stewardship and improving diagnostic capacities in high-burden regions.

Harnessing a Self-Regenerated Hybridization Circuit for Differentiating Heart Failure Patients of Varied Severity.

Heart failure (HF) is a globally threatening cardiovascular disease associated with poor quality of life and high mortality, therefore, timely diagnosis and risk prediction for HF disease are urgently needed. Herein, a compact yet robust self-regenerated hybridization circuit (SHC) aptasensor is developed for the amplified detection of N-terminal pro-brain natriuretic peptide (NT-proBNP), a "gold standard biomarker" for HF. The aptamer transduction module can specifically recognize NT-proBNP, thus initiating the cascade hybridization reaction with the successively self-regenerated triggers that reversely initiate the cross-hybridization reaction. Benefiting from the aptamer-specific recognition and the self-replicated signal amplification, the robust SHC aptasensor demonstrated a more impressive diagnostic performance for HF in elderly patients than the clinical fluorescence immunochromatography assay (FICA) in terms of positive predictive value (21 vs 17), specificity (39 vs 32), and diagnostic accuracy (37 vs 36). Furthermore, this approach allows for differentiation among HF patients with varying disease severities, achieving a sufficiently high accuracy of 78.3%, thus facilitating more timely and accurate therapeutic intervention. The versatile and reliable SHC system offers a new approach to analyzing low-abundance biomarkers from clinical rare specimens, which is highly important for early disease diagnosis and prognosis assessment.

Metal Ion-Based Chemical Coordination Amplification: A Chromophore In Situ Deposition Strategy for Visual Sensitivity-Enhanced Lateral Flow Immunochromatography Assays.

Traditional lateral flow immunochromatography assays (LFIAs) have faced low sensitivity for trace detection due to the lack of colorimetric brightness. The current strategies to improve sensitivity commonly have the disadvantages of an uncontrollable enhancement process or high background interference, leading to huge obstacles for signal readout. Herein, an in situ metal ion-based chemical coordination amplification (MICCA) strategy has been reported. Metal ion clusters on metal-organic frameworks could coordinate with chromophores to produce colored complexes for visual signal enhancement. A Zr-based metal AIEgen framework (MAF) loaded with Prussian blue was chosen as the dual-mode signal tag for colorimetric and fluorescent readout. MAF could be employed as a grafting substrate to in situ deposit chromophores through the coordination with Zr4+ clusters and arsenazo III. The process of MICCA was in situ, controllable, and free of background interference. For target cancer biomarker alpha-fetoprotein (AFP), the limit of detection (LOD) by the naked eye was 25 ng/mL, and the LODs of MICCA and fluorescence were 5 ng/mL, which was 5-fold decreased. Significantly, MICCA-LFIA could effectively differentiate between AFP-positive and AFP-negative clinical serum samples. The quantitative results were highly consistent with clinical results (R2 = 0.9927). This work explored the application of metal ion-based chemical coordination reactions in signal amplification strategies and provided ideas for high-sensitivity LFIA development.

Novel solid-phase extraction promotes simultaneous colloidal gold immunochromatographic assay of malachite green, leuco-malachite green, chloramphenicol, and semi-carbazone metabolites in aquatic products.

Solid phase extraction (SPE) using traditional column materials offers several advantages, but its ability to simultaneously extract and purify commonly used veterinary drugs, such as chloramphenicol, malachite green, leuco-malachite green and semi-carbazone, remains unproven.Therefore, in the present study, a rapid analytical method based on ultrasound-assisted SPE combined with colloidal gold test strips was developed and applied herein to determine the residues of these veterinary drugs in common aquatic products. Under optimized conditions, the method achieved a limit of detection in the range of 0.01-0.5μg/kg, inter-day RSDs of the spiked samples in the ranges of 0.99-5.58% and 1.6-7.2%, and absolute recoveries in the range of 84.2-112.9% using the colloidal gold immunoassay and enzyme-linked immunosorbent assay methods, respectively. The SPE column efficiently enriched the four veterinary drugs simultaneously, showing considerable potential for determining common veterinary drug residues in aquatic products.

Catalytic boost in dual-active sites hierarchical hollow nanozymes: An enhanced robust and sensitive immunochromatographic assay for Aspergillus flavus

Catalytic boost in dual-active sites hierarchical hollow nanozymes: An enhanced robust and sensitive immunochromatographic assay for Aspergillus flavus

P-417. Rectal Surveillance for Multi-drug Resistant Organisms colonisation Among High-Risk Patients Admitted in a Tertiary-Care Hospital in Greece

Abstract Background Antimicrobial Resistance (AMR) is a global urgent health threat that has escalated since the COVID-19 pandemic. Greece is a country with high rates of multi-drug resistant microorganisms (MDROs), including extended-sepctrum β-lactamases (ESBL), carbapenem-resistant Gram-negatives and vancomycin-resistant EnterococcI (VRE). In the present study rectal surveillance screening for the above mentioned MDROs was performed among high-risk patients admitted to our hospital. Methods High risk patients were defined as those previously hospitalized in our or other hospitals, those admitted from rehabilitation centers, oncology, and renal failure patients as well as patients that are already hospitalized in our hospital for more than 30 days. During the study period (Nov 2023 – Apr 2024), 425 patients were screened using Brilliance™ CRE Agar (Oxoid, UK) , Brillliance™ VRE Agar (Oxoid, UK) and CHROMID™ ESBL (bioMérieux, Marcy-l'Étoile, France). Carbapenem-resistant (CR) Enterobacterales and Pseudomonas aeruginosa were furtherly tested for carbapenemase production using the NG-Test CARBA 5 immunochromatographic assay (NG-Biotech, France). Isolates grown in the CHROMID™ ESBL plate were tested for ESBL production using ceftazidime and cefotaxime against ceftazidime/clavulanic acid and cefotaxime/clavulanic acid combinations. Results 185 (43,52%) patients were positive and 240 (56,47%) were negative for the MDROs investigated. Detailed results are shown in Table 1. Among the patients found positive, 89 (48,1%) were from rehabilitation centers, 53 (28,64%) were previously hospitalized elsewhere and 30 (14,05%) were hospitalized in our hospital in previous months. CR Klebsiella pneumoniae (n=76), CR P. aeruginosa (n=56) and VRE (n=57) were the most common MDROs identified. Fourty-seven patients (25,4%) died, 116 (62,7%) showed improvement and the rest remained stable or moved to other facilities. Among the 240 negatives, 35 (14, 58%) died, 197 (82,08%) were improved and 8 (3,34%) remained stable. Conclusion Our results highlight the critical situation regarding the spread of MDR bacteria among hospitalised patients, especially the high-risk ones, showing the imperative need for strengthening the already existing infection control measures. Disclosures All Authors: No reported disclosures

Comparison of AccuPower Diarrhea V1&amp;V2 RT-PCR to a Chromatographic Immunoassay for Detecting Viral Pathogens from Human Diarrheal Stool Specimens

Viruses are a frequent cause of self-limited diarrhea, with more severe outcomes in immunocompromised patients. This study aimed to compare the performance of Real-Time RT-PCR to chromatographic immunoassays (CIAs) for detecting the major gastrointestinal viruses in human stool. This study was conducted at the University Hospital of Split, Croatia, from October 2023 to May 2024. Stool samples were simultaneously analyzed with CIA (Acro Biotech Rotavirus and Adenovirus Combo Rapid Test Cassette, USA and JusChek Norovirus Rapid Test Cassette, China) and Real-Time RT-PCR (AccuPower Diarrhea V1&amp;V2 Real-Time RT-PCR, Bioneer, Republic of Korea), according to the manufacturers’ instructions. Positive percent agreement (PPA), negative percent agreement (NPA), and overall percent agreement (OPA) were calculated. For norovirus, CIA had a low PPA (25%), indicating that it missed 75% of norovirus-positive cases identified by RT-PCR. Adenovirus detection by CIA showed poor agreement with RT-PCR (PPA 0%; NPA 100%). Rotavirus detection presented a relatively better performance with CIA (PPA 90.9% and OPA 84.13%). However, the presence of false positives (15.8%) highlights the need for confirmatory RT-PCR testing. One specimen was sapovirus-RT-PCR-positive, marking the first documented case from human specimens in Croatia. Although CIA provided rapid results, limitations regarding reliability highlight the value of RT-PCR, particularly in the case of ambiguous clinical cases with negative antigenic test results and newly emerged viruses. A two-step diagnostic approach, with initial CIA screening followed by confirmatory RT-PCR, could balance cost-effectiveness with diagnostic accuracy.

Rapid on-site detection of imazaquin residue in corn and soybeans using an immunochromatographic assay.

Imazaquin (IMQ) is an imidazolinone group herbicide widely used for weed control around the world. Due to excessive use during crop production, IMQ can accumulate in corn and soybeans, positing a potential threat to human health. In this study, a hapten that had high specificity and sensitivity was designed using computer-simulated technology. A monoclonal antibody (mAb) was synthesized with a half inhibitory concentration of 0.98 ng mL-1. The mAb was incorporated into an immunochromatographic assay (ICA) for the detection of IMQ in corn and soybeans. The visual limit of detection was 10 μg kg-1 in corn with a linear range of 3.85-208.26 μg kg-1 and 5 μg kg-1 in soybeans with a linear range of 3.78-106.71 μg kg-1. Additionally, the ICA strips had excellent recovery rates, and the results were confirmed by liquid chromatography tandem mass spectrometry. Our study developed a method for the rapid on-site detection of IMQ residues in corn and soybeans.

P0329 Clostridium difficile infection associates with the need for biologics: a retrospective long-term analysis in a cohort of 102 ibd patients

Abstract Background Gastrointestinal Infections (GIs) pose a significant challenge in patients with inflammatory bowel diseases (IBD), complicating its management and triggering IBD relapses. The overlap in clinical symptoms makes complex differentiating GIs from IBD flares, impacting therapeutic decisions. This study aims at evaluating the long-term impact of GIs in IBD patients. Methods From January 2020 to September 2024, 102 IBD patients (mean age 45±16 yrs; 78 ulcerative colitis, UC and 24 Crohn’s disease, CD) experiencing a clinical relapse according to ECCO guidelines, were retrospectively evaluated. GIs were established via stool immunochromatography and multiplex molecular assay. Demographic, clinical and laboratory findings along with the treatment were noticed at the time of flare, 6 and 12 months later. Statistical analysis was performed by Mann-Witney and chi-square test as appropriate (p&amp;lt;0.05). Results Nineteen patients tested GIs positive (GIs+): 14 out of 78 (18%) UC and 5 out of 24 CD (21%) patients. Clostridium difficile infection (CDI) was found in 11 patients while non-CDI enteric pathogens (EP+) in the remaining 8 patients. All CDI patients received a first-line antibiotic treatment while no treatment was offered to EP+ patients. By stratifying for GIs at the flare time, there were no differences between GIs+ and GIs- patients with regard to age (45±16 vs46±17 yrs, p=ns), disease duration (11±9 vs 12±10 yrs, p=ns), disease activity score (Mayo score 5±2 vs 5±2, p=ns and Harvey Bradshaw index 8±4 vs 8±4, p=ns) and inflammation biomarkers (C-reactive protein 21±41 vs 22±42 mg/dl, p=ns and fecal calprotectin 1446±1751 vs 1452±1714 mcg/gr, p=ns). At 12 months after flare, the number of patients being treated with biologics increased only in GIs+ IBD patients, from 3 out 19 (16%) to 10 out 19 (53%) (Figure 1). All the 7 IBD patients who have got biologics were CDI+. Conclusion This study confirms that distinguishing a disease flare from the presence of superimposed GIs remains challenging. Notably, only in patients with CDI there was an increased use of biologics later after the flare onset. This suggest that CDI may serve as a marker of a more aggressive disease course in IBD patients.

Diagnostic methods and protocols for rapid determination of methicillin resistance in Staphylococcus aureus bloodstream infections: a comparative analysis.

To evaluate diagnostic performance of four diagnostic methods for rapid determination of methicillin resistance in S. aureus positive blood cultures (BCs). Clinical and spiked BCs were subjected to the evaluation of the following methods and protocols: a. Eazyplex® MRSA Plus loop-mediated isothermal amplification (LAMP) assay directly from BC fluid; b. MALDI-TOF MS subtyping on BC pellet extracted with Rapid Sepsityper® protocol and on 4-h short-term subculture; c. Clearview™ Culture ColonyPBP2a SA immunochromatography assay on BC pellet and on 4-h short-term subculture; d. EUCAST RAST cefoxitin screen test performed directly from BC and including reading times at 4-h, 6-h and 16-20-h. Eazyplex® MRSA plus exhibited the best performance, showing 100% sensitivity, specificity, positive predictive value, and negative predictive value, followed by PBP2a SA Culture Colony Clearview assay and EUCAST RAST cefoxitin screen. MALDI-TOF MS subtyping showed the lowest diagnostic accuracy (59.8 and 65.7% directly from BC and from 4-h subculture, respectively). In detail, sensitivity and specificity ranged from 24.3% to 20.4% and from 88.9% to 98.3% for protocols performed from BC pellet and 4-h subculture, respectively. The Eazyplex® MRSA Plus and the immunochromatographic Clearview™ PBP2a SA Culture Colony methods can provide reliable results within 1h from the start of positive BC processing. MALDI TOF MS subtyping showed unacceptable specificity by performing analysis from BC pellets, while its sensitivity depends on the prevalence of PSM-positive MRSA strains. The EUCAST RAST, based on disc diffusion, showed excellent performance with a time-to-result of at least 4h.

A Time-Resolved Fluorescent Microsphere Immunochromatographic Assay for Determination of Vitamin B12 in Infant Formula Milk Powder

Vitamin B12 (VB12) is an important nutrient, and its quality control in food is crucial. In this study, based on the principle of specific recognition of target analyte by monoclonal antibodies (mAbs), a time-resolved fluorescent microsphere immunochromatographic assay (TRFM-ICA) was developed to detect the content of VB12 in infant formula milk powder. First, the performance of the anti-VB12 mAb was evaluated, revealing a half-maximal inhibitory concentration of 0.370 ng/mL, an affinity constant of 2.604 × 109 L/mol and no cross-reactivity with other vitamins. Then, a highly sensitive TRFM-ICA was developed, with a visual limit of detection of 10 μg/kg and a cut-off value of 100 μg/kg for qualitative detection and a detection range of 4.125–82.397 μg/kg for quantitative detection. In addition, the test results of real samples were consistent with the results of quantification using microbiological methods, with a coefficient of variation of less than 10%, showing good accuracy and stability, and confirming that the TRFM-ICA is suitable for the analysis of VB12 in real infant formula milk powder samples. In this study, based on the principle of specific recognition of VB12 by monoclonal antibodies (mAbs) against VB12, a time-resolved fluorescence microsphere immunochromatographic assay (TRFM-ICA) was developed to detect the content of VB12 in infant formula by converting biological signals into optical signals.

Clostridioides difficile infection diagnosis

Clostridioides difficile is a Gram-positive, spore-forming anaerobic enteropathogen responsible for a wide spectrum of clinical diseases ranging from mild diarrhoea to pseudomembranous colitis. It is the first cause of healthcare-associated diarrhoeas, but community-associated Clostridioides difficile infections (CDI) are increasingly reported in patients without the common risk factors (age > 65 years, previous antibiotic treatment). The main C. difficile virulence factors are toxins A (TcdA) and B (TcdB), and in some cases the binary toxin. The CDI incidence has increased in Europe since the early 2000s, then decreased to reach approximately 4 cases/10,000 patients/days. C. difficile should be tested only in diarrheal stools. Children less than 3 years old are frequently colonized, therefore CDI diagnosis should be carried out only in specific cases (outbreak, Hirschsprung disease). No stand-alone method can be used for the CDI diagnosis. The European Society for Clinical Microbiology and Infectious Diseases (ESCMID) recommends a two-step algorithm with a sensitive screening test (molecular assay or glutamate dehydrogenase immunochromatographic assay). If the screening test is negative, the CDI diagnosis can be ruled out. If the screening test is positive, a second highly specific test should be used, such as toxin A/B immunochromatographic assay.

Development of a lateral flow immunochromatographic assay for the detection of Lactococcus garvieae in grey mullet (Mugil cephalus)

Development of a lateral flow immunochromatographic assay for the detection of Lactococcus garvieae in grey mullet (Mugil cephalus)

Development of a colloidal gold immunochromatographic assay utilizing dual-antibody sandwich method for detecting Orientia tsutsugamushi.

A colloidal gold immunochromatographic assay (ICA) based on a dual-antibody sandwich method was developed for the rapid and convenient detection of Orientia tsutsugamushi (O. tsutsugamushi) antigens in the early stages of infection. Monoclonal antibodies designed as 5B3 targeting the conserved region of 56 kDa outer membrane protein in various strains of O. tsutsugamushi were generated through cell fusion and screening techniques and combined with previously prepared polyclonal antibodies as detection antibodies to establish the ICA. Colloidal gold and polyclonal antibody-colloidal gold complexes were synthesized under optimized conditions. The nitrocellulose membrane was treated with 5B3 monoclonal antibody and goat anti-mouse antibody as the test and control lines, respectively. The ICA demonstrated robust sensitivity, with a minimum detection limit of 70.5 ng for the 56 kDa recombinant of the Gilliam strain. Furthermore, a detection limit of 1 × 106 copies/μL DNA of O. tsutsugamushi was determined for both PT and SJ infected cell strains by constructing a relationship between cell number and copy number of the pathogen using a quantitative PCR-based standard curve. The assay also exhibited exceptional specificity, with no false positives observed against other bacterial species, including Escherichia coli, Salmonella, Staphylococcus aureus, and Listeria monocytogenes. In summary, an ICA which is sensitive, specific, and easy to operate was successfully established for the detection of O. tsutsugamushi in scrub typhus, potentially enabling early rapid point-of-care diagnosis of scrub typhus.

Electropositive Magnetic Fluorescent Nanoprobe-Mediated Immunochromatographic Assay for the Ultrasensitive and Simultaneous Detection of Bacteria.

Immunochromatographic assays (ICAs) provide simple and rapid strategies for bacterial diagnosis but still suffer from the problems of low sensitivity and high dependency on paired antibodies. Herein, the broad-spectrum capture and detection capability of the antibody-free electropositive nanoprobe are clarified for bacteria for the first time and an ultrasensitive fluorescent ICA platform is constructed for the simultaneous diagnosis of multiple pathogens. A magnetic multilayer quantum dot nanocomposite with an amino-embedded SiO2 shell (MagMQD@Si+) is designed to enrich bacteria from solutions effectively, offer high luminescence, and reduce background signals on test strips, thus greatly improving the sensitivity and stability of ICA technique for pathogen. The superior performance of the MagMQD@Si+-based ICA through the multiplex detection of three common pathogens is demonstrated, namely, Pseudomonas aeruginosa, Streptococcus pneumoniae, and Streptococcus typhi, showing that this ICA possesses high sensitivity (8-40 cells mL-1), good reproducibility (relative standard deviation <5.4%), and high specificity for the three target bacteria. The clinical utility of the proposed method is verified through the detection of 30 real sputum samples from patients with bacterial respiratory infections, revealing that the MagMQD@Si+-based ICA has massive potential as a powerful inspection tool for the rapid, sensitive, and ultrasensitive diagnosis of bacterial infections.

Hapten prediction, monoclonal antibody preparation, and development of an immunochromatographic assay for the detection of fenamiphos.

Fenamiphos (FENA) is an organophosphorus insecticide, and its residues in fruits, vegetables, and the environment have raised concerns. Therefore, it is very important to develop a simple, rapid, and accurate method for FENA detection. In this study, a novel FENA hapten was designed and predicted based on computer-aided simulation technology, and high-performance anti-FENA monoclonal antibodies were screened using a matrix effect-enhanced screening method, with a half-maximal inhibitory concentration of 1.269 ng/mL. Furthermore, a colloidal gold immunochromatographic assay (ICA) was established for the detection of FENA, with calculated limits of detection of 1.030 μg/kg, 0.515 μg/kg, 0.250 ng/mL, and 0.405 μg/kg in oranges, cowpeas, river water, and soil. Spiked recovery experiments and real sample validation showed that the detection results from the ICA and LC-MS/MS were consistent, with a CV < 10 %, indicating that the ICA had good accuracy and stability and shows promise as a rapid screening method for FENA in fruits, vegetables, and the environment.

Generalized linear modeling of HCV infection among medical waste handlers in Sidama region, Ethiopia.

There is limited evidence on prevalence and risk factors for hepatitis C virus (HCV) infection among waste handlers in Sidama region, Ethiopia; however, this knowledge is necessary for effective prevention of HCV infection in the region. A cross-sectional study was conducted among randomly selected waste collectors from October 2021 to 30 July 2022 in different public hospitals of Sidama region of Ethiopia. Serum samples were collected from participants and screened for anti-HCV using rapid immunochromatography assay. Socio-demographic and risk factor information of waste handlers was gathered by pretested and well-structured questionnaires The generalized linear model (GLM) was conducted using R software, and P-value <0.05 was declared statistically significant. From a total of 282 participating waste handlers, 16 (5.7%) (95% CI = 4.2-8.7) were infected with hepatitis C virus. Educational status of waste handlers was the significant demographic variable that was associated with hepatitis C virus (AOR = 0.055; 95% CI = 0.012-0.248; P = 0.000). More married waste handlers, 12 (75%), were HCV positive than unmarried, 4 (25%) and married waste handlers were 2.051 times (OR = 2.051, 95% CI = 0.644-6.527, P = 0.295) more prone to HCV infection, compared to unmarried, which was statistically insignificant. The GLM showed that exposure to blood (OR = 8.26; 95% CI = 1.878-10.925; P = 0.037), multiple sexual partners (AOR = 3.63; 95% CI = 2.751-5.808; P = 0.001), sharp injury (AOR = 2.77; 95% CI = 2.327-3.173; P = 0.036), not using personal protective equipment (AOR = 0.77; 95% CI = 0.032-0.937; P = 0.001), contact with jaundiced patient (AOR = 3.65; 95% CI = 1.093-4.368; P = 0.0048) and unprotected sex (AOR = 11.91; 95% CI = 5.847-16.854; P = 0.001) remained statistically significantly associated with HCV positivity. The study revealed that there was a high prevalence of hepatitis C virus infection among waste handlers in Sidama region, Ethiopia. This demonstrated that there is an urgent need to increase preventative efforts and strategic policy orientations to control the spread of the hepatitis C virus.

Immunochromatographic Lateral Flow Assays to Detect Filovirus Nucleoproteins.

The recent large outbreaks of Ebola virus disease in West Africa and the Democratic Republic of the Congo have highlighted the need for rapid diagnostic tests to control this disease. In this chapter, the development of immunochromatographic lateral flow assays to detect filovirus nucleoproteins is described as an example of designing rapid diagnostic tests.

FilmArray® Effectively Detects All Clades of F41 but Encounters Challenges with Other Adenovirus Species.

The BioFire FilmArray® Gastrointestinal (GI) Panel, a widely used diagnostic tool, is designed to detect the genetic material of 22 common pathogens responsible for gastroenteritis, including viruses, bacteria, and parasites. It can detect human adenovirus (HAdV) species F, particularly serotypes F40 and F41, which are the major causes of diarrhea and mortality in children. However, its potential shortcomings in detecting other HAdV species limit its effectiveness in broader HAdV detection in clinical settings and outbreak investigations. The aim of this study was to evaluate the ability of the GI Panel to detect three clades of HAdV-F41 and other HAdV species (viz., A31, B3, C1, C2, C5, C2/6, and D56) in Japan. Eighteen stool samples were analyzed, five of which contained HAdV-F41, and 13 contained other HAdV species, as confirmed via PCR and sequencing. Although the GI Panel reliably detected all clades of HAdV-F41, it failed to detect any other species, highlighting its limited diagnostic utility beyond F40/41 serotypes. Considering the high false-negative rate for non-F40/41 species, integrating complementary diagnostic methods such as PCR is crucial for comprehensive HAdV detection. These findings underscore the limitations of the GI Panel in detecting non-F40/41 species, such as HAdV-C (commonly associated with pediatric gastroenteritis) and other species that are important in immunocompromised patients. Complementary diagnostic methods, such as PCR or immunochromatographic assays, are essential to ensure accurate HAdV detection, especially in vulnerable populations.

Outbreak of carbapenem resistant Klebsiella pneumoniae in a neurorehabilitation unit: Genomic epidemiology reveals complex transmission pattern in a tertiary care hospital.

Infections by carbapenem-resistant Enterobacterales (CRE) in hospitals represent a severe threat but little is known on outbreaks in rehabilitation wards caused by Klebsiella pneumoniae producing Klebsiella pneumoniae Carbapenemase (KPC-Kp). We report an outbreak by KPC-Kp, in a neurorehabilitation unit in Italy, analysed through whole-genome sequencing (WGS) for transmission routes reconstruction to improve management of KPC-Kp infections in rehabilitation units. We investigated cases and KPC-Kp isolates collected from February to October 2022 from hospital surveillance. Carbapenem resistance was identified with disk diffusion and minimum inhibitory concentration tests, carbapenemase production through immunochromatographic lateral flow assays. All isolates were genotyped through WGS to highlight possible phylogenetic relationships. The most likely transmission networks of KPC-Kp were reconstructed with Bayesian discrete-time stochastic models. Nineteen patients were colonized by KPC-Kp. Two isolates belonged to sporadic sequence types (STs; ST348 and ST219) whereas 9 of 19 and 8 of 19 isolates belonged to ST307 and ST716, respectively. Among the ST307 isolates, we identified two genomically distinct clusters of five and two cases. All ST716 isolates were highly similar. Genotyping and the reconstruction of transmission networks of KPC-Kp based on genomic data identified seven independent introductions into the neurorehabilitation unit rather than a single outbreak as initially hypothesized before genomic investigation. Three of the seven introductions generated chains of secondary infections, whereas the remaining four remained single cases. The outbreak root-causes were identified in temporary staff shortage and insufficient microbiological surveillance. Measures were adopted accordingly and the outbreak ended. The study highlights the critical role of genomic epidemiology in hospital outbreaks. © 2025 The Author(s). Published by Elsevier Ltd on behalf of International Society for Antimicrobial Chemotherapy.