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Background. Carbapenem-resistant Gram-negative bacteria (CR-GNB), particularly metallo-β-lactamase (MBL) producers, are WHO critical-priority pathogens. In Libya, laboratory-based data are scarce, and no study has assessed endemic medicinal plants as adjunctive options. Objectives. To generate baseline data on carbapenem resistance and MBL production among clinical Gram-negative pathogens in Misurata, Libya, and to preliminarily evaluate the antibacterial activity and phytochemical composition of Arbutus pavarii extracts. Methods. We conducted a cross-sectional study of 244 non-duplicate clinical isolates. Carbapenem susceptibility was determined by Kirby-Bauer disc diffusion; MBL production was confirmed by double-disc synergy and combined-disc tests. Ethanolic and aqueous extracts from A. pavarii leaves, stems and fruits were tested against resistant isolates by disc diffusion. Phytochemicals were profiled by HPLC. Results. The predominant carbapenem-resistant species were Acinetobacter baumannii (29.5%), Klebsiella pneumoniae (26.2%) and Pseudomonas aeruginosa (19.7%). Resistance to both imipenem and meropenem exceeded 60% across these isolates, and MBL activity was detected in 54.5% of carbapenem-resistant K. pneumoniae. Among plant extracts, the aqueous leaf extract showed the highest antibacterial activity against MBL-producing isolates (mean inhibition zone 9.46±7.61 mm at 100%), slightly exceeding the corresponding ethanolic extract (9.31±7.30 mm). Both extracts demonstrated concentration-dependent effects (P<0.05; ANOVA/Kruskal-Wallis). HPLC analysis identified catechin and quercetin as major components, which may underlie the observed activity. Conclusions. This first laboratory-based report from Libya documents high rates of CR-GNB and MBL production and introduces A. pavarii as a promising endemic plant with adjunctive antibacterial potential. Findings support enhanced AMR surveillance and the exploration of resource-sensitive alternatives in African healthcare settings.

Tuberculosis (TB) remains a large global health threat, including increasing cases in generally low-incidence areas of the USA. However, the knowledge, attitudes and practices (KAP) regarding TB in these low-incidence areas are underexplored, precluding planning for effective health communication in these areas regarding travel to high-incidence areas or potential future outbreaks in currently low-incidence areas. Using the health belief model as a theoretical framework, we developed a KAP survey to assess public perceptions of TB in Colorado, a currently low-incidence area. We collected complete responses from n=225 adults. We found that participants had higher self-assessed knowledge than actual knowledge about TB. We also found that while participants recognized TB as a global health threat, they were not personally worried about contracting TB. However, a portion of participants indicated that they would feel shame if they contracted TB. Public knowledge and risk perception about TB could be improved by providing information in low-incidence areas on the public health burden of TB. Additionally, providing health communication to focus on emotion management and reducing stigma about the disease would be important to promote healthcare-seeking and treatment compliance in case of a future outbreak.

The rise of multidrug-resistant Enterobacterales and Pseudomonas aeruginosa has diminished the reliability of conventional antibiotics for treating Multidrug Resistant (MDR) infections. The combination of ceftazidime-avibactam with aztreonam has demonstrated in vitro synergism against multidrug-resistant organisms, notably metallo-beta-lactamase-producing strains. Treatment with the ceftazidime-avibactam/aztreonam combination may provide clinical benefits for patients with multidrug-resistant bacterial infections. The present study aimed to detect genes encoding carbapenem resistance in clinical strains and to determine the efficacy of ceftazidime-avibactam/aztreonam against carbapenemase co-producers. A cross-sectional research study was conducted on 62 carbapenem-resistant clinical isolates collected from November 2022 to February 2024. Ceftazidime-avibactam/aztreonam synergy against 55 carbapenemase producers [New Delhi metallo-beta-lactamase (NDM), imipenem-hydrolysing metallo-beta-lactamase (IMP), Verona Integron-encoded metallo-beta-lactamase (VIM) and oxacillinase-48 (OXA-48)] was determined using the disc diffusion method. Data analysis was performed by chi-square test. Ceftazidime-avibactam/aztreonam synergy was identified against 25 (64.1%) out of 39 isolates exhibiting the NDM gene, seven (77.8%) out of nine isolates that were co-producers of NDM and OXA-48 genes, two (50%) out of four isolates co-producing NDM and VIM carbapenemase genes and a single isolate (33.3%) out of three isolates with NDM, VIM and OXA-48 genes. A wide zone of 3-23 mm diameter was observed for Enterobacterales and 6-7 mm for P. aeruginosa with ceftazidime-avibactam/aztreonam in relative to ceftazidime-avibactam and aztreonam discs when tested alone. More than 30% of isolates showed a statistically significant difference in zone diameter for the ceftazidime-avibactam/aztreonam combination (P<0.05), when compared with the zone size for ceftazidime-avibactam and aztreonam discs when tested alone. The present study showed the in vitro effectiveness of the ceftazidime-avibactam/aztreonam combination against 63.6% of carbapenem-resistant isolates studied. The disc diffusion method requires less technical expertise, and the test result aids in identifying true clinical synergy by observing the widening of the zone diameter that exceeds the aztreonam susceptibility breakpoint.

Meyerozyma guilliermondii, a haploid yeast (phylum Ascomycota), is useful in bioprocessing and bioremediation, and is an infrequent pathogen of humans. The availability of highly accurate, long-read DNA sequencing methods provided the opportunity to improve the M. guilliermondii genome assembly. Using Pacific Biosciences (PacBio) HiFi technology, we generated a chromosome-level, telomere-to-telomere assembly for the M. guilliermondii type strain ATCC 6260. This assembly closed gaps in the current reference sequence and resolved a translocation artefact that affected the size and structure of chromosomes 4 and 5. The improved genome sequence is available publicly and will facilitate future studies of this species.

Introduction. Acute disseminated encephalomyelitis (ADEM) is a well-described neurological disorder that follows acute infection, vaccination and organ transplantation. It is characterized by sudden and widespread areas of inflammation in the central nervous system. Previous case reports have described ADEM with evidence of either recent or current herpes simplex virus type 1 infection. However, here, we report a rare, to our knowledge never before documented, case of ADEM associated with herpes simplex virus type 2 (HSV-2). Case report. A 20-year-old man presented with weakness and sensory disturbance to the lower limbs, which had gradually progressed over the preceding 7 days, with associated fever, urinary retention and bowel incontinence. Magnetic resonance imaging was in keeping with a diagnosis of ADEM with mainly spinal involvement. Lumbar puncture revealed lymphocytic pleocytosis with elevated protein, and PCR was strongly positive for HSV-2. He was treated with aciclovir and dexamethasone, along with broad-spectrum antibiotics until negative bacterial and mycobacterial culture results were obtained. His functional status improved over the following months, but, despite prolonged rehabilitation, neurological sequelae remain. Conclusion. HSV-2 may be considered a possible aetiological agent in cases of ADEM.

Background. Influenza C virus (ICV) is a lesser known member of the Orthomyxoviridae family, primarily causing respiratory tract infections in children. Co-infection with WU polyomavirus (WUPyV), a recently identified human polyomavirus, has been rarely reported. This study presents the first laboratory-confirmed case of ICV infection in Sri Lanka and its co-infection with WUPyV. Methods. Nasopharyngeal and oropharyngeal swabs were collected from children aged 3 months to 14 years with respiratory tract symptoms between November 2022 and February 2023. Samples were screened using multiplex real-time PCR (RT-PCR) and Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) RT-PCR. A nasopharyngeal swab from a 14-month-old infant showing an insignificant curve in respiratory PCR was subjected to whole-genome sequencing using the Illumina platform. Data were analysed for genomic characterization, and phylogenetic analysis was performed using the haemagglutinin-esterase gene of ICV. Results. Full-genome sequencing identified ICV and WUPyV in the sample. Phylogenetic analysis revealed that the ICV isolate belonged to the C/Sao Paulo lineage. The patient presented with mild symptoms, including fever, cough and cold, with normal inflammatory markers, and recovered with supportive care. Discussion. This case highlights the importance of considering ICV in paediatric respiratory illnesses, despite its under-diagnosis due to limited diagnostic tools. Unlike influenza A and B, ICV lacks neuraminidase, rendering neuraminidase inhibitors ineffective. The absence of ICV in current influenza vaccines further complicates preventive strategies. Co-detection of WUPyV raises questions about its role as a co-pathogen, with its clinical significance requiring further investigation. Conclusion. This report underscores the need for enhanced molecular diagnostic techniques and surveillance to better understand the epidemiology and clinical impact of ICV and its co-infections.

Many microbial culture collections, like the UK's National Collection of Type Cultures, add biological material such as bacterial strains to their holdings over time in a process known as accessioning. Here, we report on the 101 bacterial strains made available to scientists in the UK and globally by the National Collection of Type Cultures in 2023. Strains that are received are preserved, identified to species level and confirmed to be viable and pure. Genomic and metadata (where these are available) are made accessible via the UKHSA Culture Collections online catalogue. Commentary on the strains' provenance and significance is presented, and wider trends in accessioning between 2017 and 2023 are examined. On average, ~101 strains were made available to the scientific community each year between 2017 and 2023. Fewer strains of veterinary provenance were made available than any other kind of strain, highlighting a need to accession more of these strains. However, there has been growth in the proportion of strains that are either antimicrobial resistant or type strains of novel microbial taxa, demonstrating that the NCTC program of accessioning helps support its function as a contemporary public health resource and repository for prokaryotic taxonomists.

Although there is a well-established connection between the gut microbiome and obesity, the specific mechanisms by which microbes regulate cell signalling, inflammation and adipocyte growth to influence disease severity in obese patients remain largely unclear. Subsequently, while obesity itself is a well-established risk factor for various cancers, the exact mechanisms by which it drives disease progression are not yet definitively known. In this study, we explored the link between obesity-associated microbiome alterations and cancer progression by analysing microbial abundance in tissue samples from obese and cancer patients, and we identified specific microbes correlated with body mass index (BMI) that are associated with key cancer-related pathways. Notably, BMI-associated microbial species such as Pseudomonas fluorescens and Lactobacillus sakei were linked with both pro-tumour and anti-tumour progression in cancer patients. Additionally, microbes found to be abundant in cancer and obese tissue, such as Pseudomonas baetica, were significantly associated with the upregulation of certain oncogenic signalling pathways. BMI-associated microbes were also correlated with chemokine signalling and TFR2/NFkB-related genes. Both of these have well-established roles in inflammatory activity and inflammasome expression, a critical step in obesity-related cancer progression. Therefore, these microbes were found to be associated with variations in disease prognosis and patient survival. This study provides new insights into how obesity-related microbiome dysbiosis may be associated with cancer development and aims to introduce novel potential avenues for precision medicine approaches in cancer treatment.

Fresh produce-associated outbreaks of the foodborne pathogen Escherichia coli O157 are responsible for a number of disease cases, hospitalizations and deaths. In many cases, the source of contamination can be linked to the growing media of the food, although pathogen detection is problematic in these complex soil ecosystems. In this study, direct quantitative real-time PCR without pre-enrichment was used to detect 310 copies of the Tir gene, using a primer sequence specific to E. coli O157, in horticultural compost purchased from a commercial supplier. The pathogen could not be cultured on selective media but was visualized using peptide nucleic acid fluorescence in situ hybridization and cell elongation viability assay, confirming the viability. Enumeration of elongated E. coli O157 determined that there were 205 live cells per gram of compost. The nonculturability and confirmation of viability of the pathogen indicates its viable but nonculturable (VBNC) status. The detection of VBNC foodborne pathogens in environmental samples challenges current understanding of the nature of foodborne pathogen contamination.

Cryptococcus albidus, an emerging pathogen, poses diagnostic and therapeutic challenges, especially in immunocompromised patients. We report a case of C. albidus meningitis in a young T-cell acute lymphoblastic leukaemia patient, initially suspected to have Herpes Simplex Virus (HSV) encephalitis. CSF analysis confirmed C. albidus, leading to antifungal therapy with liposomal amphotericin B and flucytosine, resulting in clinical improvement. Elevated procalcitonin levels suggest a potential role in fungal infections. This case underscores the importance of early identification and appropriate treatment in C. albidus meningitis.