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Background: Emerging carbapenem-resistant Klebsiella pneumoniae ( K. pneumoniae ) (CRKP) bacteremias are presenting significant public health risks due to limited treatment options and increased mortality. K. pneumoniae isolates exhibit carbapenem resistance rates that vary from 25% to 50% throughout the European continent, including our country., Aims: To assess the characteristics of CRKP bacteremia, a condition that has recently demonstrated an increasing prevalence in our center. We sought to ascertain the resistance rates of isolated strains to antibiotics other than carbapenems, identify the responsible carbapenemase genes, evaluate the efficacy of antibiotics, determine mortality rates, explore clonality among strains, and investigate the influence of the COVID-19 pandemic on all these factors., Study Design: Retrospective observational study., Methods: This study included patients aged 18 and older who had experienced meropenem-resistant K. pneumoniae bacteremia. Meropenem resistance was confirmed by employing the Kirby-Bauer disk diffusion method. Meropenem minimum inhibitory concentration (MIC) levels were determined using the gradient test, while colistin MIC levels were ascertained using the disk elution technique. Carbapenemase genes were evaluated via colony polymerase chain reaction (PCR), and clonality analysis was performed using the arbitrarily primed PCR technique., Results: The study comprised 230 patients, with a mean age of 63.1 ± 15.9 years, of whom 58.7% were male. Oxacillinase-48 (OXA-48) was detected in 74.8% of the patients, New Delhi metallo-beta-lactamase (NDM) in 12.6%, OXA-48 + NDM in 7.8%, and KPC in 4.8%. The 14-day and 30-day mortality rates were 57% and 69.6%, respectively. Multivariate analysis of the 30-day mortality revealed several crucial factors, including bacteremia development in the intensive care unit, the occurrence of bacteremia during the COVID-19 pandemic, polymicrobial bacteremia, the use of indwelling intravenous catheters, a platelet count of ≤ 140,000/μl, procalcitonin levels of ≥ 6 μg/l, and a Charlson comorbidity score ≥ 3. Notably, the OXA-48 and KPC genes were upregulated significantly during the COVID-19 pandemic, while the NDM gene groups were downregulated. Additionally, both 14-day and 30-day mortality rates increased significantly., Conclusion: In this study, the most prevalent carbapenemase gene was OXA-48; however, there has been a recent increase in KPC genes. No dominant epidemic strain was identified through clonality analysis. The clustering rate was 68% before the pandemic, increasing to 85.7% during the pandemic. The significance of infection control measures is underscored by the rise in both clustering and mortality rates during the COVID-19 pandemic., Competing Interests: Conflict of Interest: The authors declare that they have no conflict of interest.

Background: SARS-CoV-2 is a threat to humanity. Both the spike (S) protein and its receptor binding domain (sRBD) are extensively used for rapid detection. Although real-time reverse transcription polymerase chain reaction (rRT-PCR) is mostly used method for the molecular detection of SARS-CoV-2, rapid assays for antigenic detection are always needed. Lateral flow assays (LFAs) are the most commonly used tests for this purpose, and aptamers having stability and long shelf life are used as capture reagents., Objective: This study aimed to develop the LFAs based on the aptamer pairs for the antigenic detection of SARS-CoV-2 with the naked eye., Method: Gold nanoparticles (AuNPs) were used as labels, and six sandwich models by three different aptamers were prepared using 4 μM and 8 μM probes and two kinds of membranes for developing the LFAs., Results: The 8 μM probe concentration and M2 membrane showed the best recognition of both the synthetic sRBD and SARS-CoV-2 coming from the naso/oropharingeal swabs by designed LFAs as 100% sensitivity and 93.3% specificity compared to the antibody-detecting LFAs., Conclusions: Our developed strip assays based on aptamer pairs recognized the target directly in 5-6 min with the naked eye. It was also concluded that aptamer pairs, membrane types, assay buffers, and probe concentrations have a significant role in the detection of SARS-CoV-2 by LFAs., Highlights: The detection of SARS-CoV-2 in clinical samples was demonstrated with the best aptamer pairs, sensitively and selectively among the designed six aptamer pairs for LFAs. Developed LFAs can be an alternative method to the conventional antibody-based LFAs for SARS-CoV-2 detection., (© The Author(s) 2024. Published by Oxford University Press on behalf of AOAC INTERNATIONAL. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

SARS-CoV-2 is still threat and mostly used detection method is real time reverse transcriptase polymerase chain reaction (rRT-PCR) for the open reading frame (Orf1ab), RNA-dependent RNA polymerase (RdRp), nucleocapsid (N) and envelope (E) genes of virus. However, rRT-PCR may have false negative rate for the nucleic acid detection. Since the RdRp/Orf1ab has high sensitivity for the molecular detection, two sandwich models, Model 1A-Model 1B, based on hybridization on lateral flow assay (LFA) were designed here and applied with the synthetic and clinical samples of RdRp/Orf1ab. In this purpose colloidal gold nanoparticles (AuNPs) were used as label. Membranes having different flow rate, three oligonucleotide probe concentrations and running buffers were used. Although synthetic target sequence was recognized by all the LFAs, PCR products obtained from either the synthetic plasmid DNA or oro/nasopharyngeal swabs were detected by Model 1 A using W12 membrane. Designed strip assays detected the RdRp/Orf1ab of the clinical samples as 100% sensitivity and specifity. It means that they might be used for the detection of virus and can be modified for the recognition of mutant genes of virus. These findings also demonstrated the importance of membranes, sandwich models, probe concentrations and sample contents for developing LFAs for viral detection., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Introduction: A vaccine against coronavirus disease 2019 (COVID-19) is critically needed for older adults because of the increased morbidity and mortality rates., Methodology: In this prospective study, we analysed the titre magnitude of the IgG antibodies directed against the SARS-CoV-2 Spike Protein S1 (S1-RBD) antigen in both CoronaVac and Pfizer-BioNTech groups. The samples were tested to detect antibodies that bind to the receptor-binding domain of the spike protein of SARS-CoV-2 using the Enzyme-Linked Immunosorbent Assay (ELISA) technique with SARS-CoV-2 IgG II Quant. The cut-off value was > 50 AU/mL. GraphPad Prism software was used. Statistical significance was defined at p < 0.05., Results: The CoronaVac group (12 females, 13 males) had a mean age of 69.64 ± 1.38 years. The Pfizer-BioNTech group (13 males, 12 females) had a mean age of 72.36 ± 1.44 years. The anti- S1-RBD titre decrease rate from the 1st to the 3rd month for CoronaVac and Pfizer-BioNTech groups was 74.31% and 86.48%, respectively. There was no statistically significant difference in the antibody titre between the 1st month and 3rd month for the CoronaVac group. However, there was a significant difference between the 1st and 3rd month in the Pfizer-BioNTech group. In addition, there was no statistically significant difference in the genders between the 1st and 3rd month of the antibody titres for both the CoronaVac Pfizer-BioNTech group., Conclusions: The levels of anti-S1-RBD, the preliminary outcome data of our study, represents one piece of the puzzle of humoral response and duration of vaccination protection., Competing Interests: No Conflict of Interest is declared, (Copyright (c) 2023 Meryem Guvenir, Ozel Yuruker, Osman Yetkin, Kaya Suer, Baris Otlu.)

There are limited publications about the Coronavirus disease 19 (COVID-19) clinic developing in the patients with active tuberculosis (TB). In this study, it was aimed to determine some clinical features of patients diagnosed with TB who also had COVID-19. In this retrospective cross-sectional study, 71 patients with COVID-19 were evaluated out of a total of 595 patients diagnosed with TB in our province between 2015 and 2021. After contracting COVID-19, a total of nine (12.6%) TB patients were hospitalized, five (7%) patients were admitted to the intensive care unit, three (4.2%) were intubated, and one (1.4%) died due to severe COVID-19. The frequency of such health problems was found to be higher than the normal population living in the same province. None of these complications were observed in a total of 40 female TB patients, and the hospital and intensive care unit admission rates for men were significantly higher than for women. The results of this study showed that men with active TB had more health problems due to COVID-19 than the normal population. Comprehensive studies are needed to detail the resilience of female TB patients against COVID-19.

We investigated the change in the epidemiology of nosocomial bloodstream infections (BSIs) caused by multidrug-resistant bacteria during Coronavirus Disease (COVID-19) and antibiotic consumption rates at a pandemic hospital and at the Oncology Hospital which operated as COVID-19-free on the same university campus. Significant increases in the infection density rate (IDRs) of BSIs caused by carbapenem-resistant (CRAB) and ampicillin-resistant (ARE) were detected at the pandemic hospital, whereas carbapenem-resistant BSIs were increased at the non-pandemic Oncology Hospital. Pulsed field gel electrophoresis showed a polyclonal outbreak of CRAB in COVID-19 intensive care units. Antibiotic consumption rates were increased for almost all antibiotics, and was most significant for meropenem at both of the hospitals. Increased IDRs of CRAB and ARE BSIs as well as an increased consumption rate of broad-spectrum antibiotics emphasize the importance of a multimodal infection prevention strategy combined with an active antibiotic stewardship program.