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Background. Human immunodeficiency virus (HIV) is the major cause of failure to reach targets of tuberculosis (TB) control in settings with high HIV loads. TB, on the other hand, enhances the progression of HIV infection to AIDS. This study was done to understand the epidemiological and clinical profile of HIV-TB co-infected patients and to study the impact of TB on the recovery of CD4 counts. Methodology. An observational study was conducted in which of the 573 patients newly diagnosed with HIV infection and enrolled at the antiretroviral therapy (ART) centre, King George's Medical University, Lucknow, between May 2021 and June 2022, 80 patients who also had newly diagnosed TB were included. These HIV-TB co-infected patients were analysed for demographic factors. Also, clusters of differentiation 4 (CD4) counts were done at the time of enrolment on ART and then later, ~6 to 8 months of recieving ART and anti-tubercular treatment (ATT) initiation. For comparison, of the 493 HIV-only patients, 50 age- and gender-matched consecutive patients for whom baseline and follow-up CD4 counts were available were enrolled as controls. The change from baseline CD4 count was calculated using a paired t-test and Wilcoxon signed rank test. Results. In the present study, among HIV-TB co-infected patients, baseline CD4 levels were 194.52±162.27, and follow-up CD4 levels were 285.09±170.33. A statistically significant increment of 90.57±165.60 in mean CD4 levels was observed (t=4.019; P<0.001). Likewise, in only HIV-positive patients, a statistically significant increment of 125.26±191.48 (35.75%) cells in mean CD4 levels was observed (t=4.626; P<0.001). The increase in CD4 counts in HIV only population was significantly higher than that observed in HIV-TB co0infected patients. Conclusion. Though significant rise in CD4 counts was observed in both HIV-TB co-infected patients and HIV-only patients after 6 to 8 months of appropriate therapy, the rise was significantly higher among the HIV-only group as compared to the HIV-TB co-infected group.

Objective. Hepatitis B virus (HBV) spontaneous mutations may impact the severity of liver disease. This study aimed to assess the mutations in the pre-core (PC) region in HBV-HIV (human immunodeficiency virus) co-infected patients. Additionally, we explored its association with genotypes and examined the clinical implications. Methods. A total of 100 HBV-HIV co-infected patients and 50 HBV mono-infected patients were included in the study. We focused on the PC region of the HBV genome, sequencing it to identify PC mutant variants. PCR products were quantified via spectrophotometry and sequenced using the Sanger method. The resulting sequences were assembled, annotated and aligned in a single reading frame. Subsequent mutational and phylogenetic analyses were performed using UGENE software to determine the genotypes of the isolates. Results. The PC region was successfully amplified and sequenced in 27 samples, comprising 16 from HBV-HIV co-infected patients and 11 from HBV mono-infected patients. Phylogenetic analysis identified two HBV genotypes: genotype D, which was predominant and found in 24 samples (88.9%), and genotype A, present in 3 samples (11.1%). A T-to-C mutation at nucleotide position 1912 was detected in 48.1% of the patients. Furthermore, several additional PC mutations were observed, including A1850T, C1858T, G1899A, G1862T, G1951T, T1812C and T1809G, along with novel mutations such as C1936T, A2011G, T2020A and C2044T. Notably, the prevalence of these PC mutations did not significantly differ between the HBV mono-infected and HBV-HIV co-infected groups. Conclusion. This study underscored the prevalence of PC mutations in HBV-HIV co-infected patients. Although several of these mutations have been previously reported, our findings also revealed novel variants. Further research is needed to elucidate the clinical significance of these new mutations.

Diarrhoeal diseases remain a significant global health challenge, particularly in developing regions such as Africa, Asia and Latin America, where they are a leading cause of child mortality. Contaminated food, including raw or undercooked vegetables, is a major transmission route for diarrhoeal pathogens such as norovirus, Campylobacter, non-typhoid Salmonella and pathogenic Escherichia coli. This study aimed to assess the prevalence of enterotoxigenic E. coli (ETEC), a key diarrhoeal pathogen, in fresh produce and prepared salads in Mexico City. A total of 128 samples, including prepared salads (lettuce, carrots and tomatoes) and unprocessed coriander and lettuce, were analysed over 2 years using protocols from the Bacteriological Analytical Manual and the Official Mexican Standard (NOM) SSA 210. Genotyping was performed to detect ETEC-specific virulence genes encoding heat-stable and heat-labile enterotoxins (st and lt), respectively. ETEC was identified in 9.9% of the total samples, representing 51.56% of the confirmed E. coli isolates. Contamination rates varied by food type, with coriander showing the highest prevalence (78.78%), followed by lettuce (9.09%) and prepared salads from La Vicentina Market (9.09%) and La Purísima Market (3.03%). Genotyping revealed that 12.12% of the ETEC-positive samples carried both st and lt genes, while 33.3 and 54.6% carried only the lt or st gene, respectively. In lettuce samples, 9.09% were positive for ETEC, with 3.03% carrying the lt gene, 3.03% the st gene and 3.03% both genes. Similarly, in coriander, 21.21% were positive for the lt gene, 51.51% for the st gene and 6.06% for both genes. These findings highlight the widespread presence of ETEC in fresh produce sold in Mexico City, posing a significant public health risk, particularly given the increasing consumption of raw vegetables. The study provides the first reported data on ETEC contamination ratios in Mexico City, emphasizing the urgent need for improved food safety measures, including better hygiene practices during production, handling and preparation of fresh produce. This research underscores the importance of ongoing surveillance and preventive strategies to mitigate the risk of foodborne diarrhoeal diseases in urban populations.

Little is known regarding the vaginal microbiota of sheep that undergo spontaneous abortions. The aim of this pilot study was to characterize, using 16S rRNA gene sequencing and shotgun metagenomics, the vaginal microbiota throughout the gestation of two ewes (Ewe1 and Ewe2) that spontaneously aborted. To achieve this, weekly vaginal swabs were collected from the ewes prior to breeding until pregnancy testing; thereafter, biweekly swabs were collected until the spontaneous abortion occurred. Based on the 16S rRNA sequencing data, Ewe1's vaginal microbiota, overall, contained high abundances of Histophilus (12.9% relative abundance), Staphylococcus (10.8% relative abundance) and Unclassified Pasteurellaceae (8.7% relative abundance). Most notable was the high abundance of Campylobacter following the abortion in Ewe1's vaginal microbiota. Ewe2's vaginal microbiota was characterized by high abundances of Pasteurella (41.7% relative abundance) throughout gestation. Shotgun metagenomic sequencing produced two high-quality metagenome-assembled genomes (MAGs), identified as Campylobacter jejuni and Histophilus somni. The C. jejuni MAG had 99.95% average nucleotide identity to the most abundant sheep abortive C. jejuni clone in the USA. The H. somni MAG was most similar to a pathogenic H. somni strain and contained genes that contribute to serum resistance and sialic acid utilization. The results presented here demonstrate the need for continued research into the vaginal microbiota, specifically to identify potential predictors of spontaneous abortion.

Consequences of Shiga toxin-producing Escherichia coli (STEC) infection can range in severity from asymptomatic infection to haemolytic uraemic syndrome, renal failure and death. Groundwater-derived drinking water is an important route for STEC transmission. Detection of STEC in water is crucial for timely response and public health interventions; however, currently used culture-based methods are time-consuming and laborious. Therefore, there is a need for rapid methods that maintain high sensitivity and specificity [1]. We describe a novel, sensitive, enrichment-free water filtration method using a convenient sample volume (100 ml) to detect DNA markers of STEC serogroups and virulence factors within 6 h. Quantitative real-time PCR (qPCR) was used to detect and quantify the most common STEC infection-associated serogroups globally, O157 and O26. Real-time PCR was used to detect genetic determinants of STEC virulence (stx1, stx2 and eae genes) and specific marker genes for the clinically relevant serogroups O111, O103, O145 and O104. Results showed that the novel method can detect as low as 5 c.f.u. ml^-1 of STEC in water. The limit of detection for O157 and O26 qPCR assays was two and six copies, respectively. Groundwater and surface water samples (n=28) were collected and processed using the novel method. STEC O157 and O26 serogroups were detected in 23 out of 28 (82.1%) samples (mean 5.2×10⁴ copies/reaction) and 19 out of 28 (67.9%) samples (mean 7.83×10⁴ copies/reaction), respectively. Shiga toxin genes stx1 or stx2 were detected in 15 out of 28 (53.6%) and 9 out of 28 (32.1%) samples, respectively. The virulence factor intimin gene eae was detected in 24 out of 28 (85.7%) samples. STEC serogroups O111, O103, O145 and O104 were detected in 15 out of 28 (53.6%), 10 out of 28 (35.7%), 11 out of 28 (39.3%) and 15 out of 28 (53.6%) samples, respectively. This novel method reproducibly detects low copies of STEC in low-volume fresh water and has the potential to be used for the detection and quantification of waterborne bacterial pathogens.

Digital education in the life sciences has seen several remarkable advances in recent years, not least with the advent of visual and immersive technologies that bring into focus the conceptually challenging abstract concepts that underpin molecular biology and the life sciences. In some cases, limitations in visualizing and modelling these concepts can prove to be a barrier to learning. Providing new entry points to learning through 'doing' or 'seeing' could prove to be a significant enhancer of engagement, unlocking hidden potential in our student cohorts and increasing the uptake of science as a subject of choice in higher education. In this study, second-level education teachers and higher education practitioners worked in partnership to explore the current state of the art around design and integration of immersive virtual reality simulations for the teaching of microbial and human cell structures in the classroom. We also considered the wider application of virtual reality and immersive learning technologies for science, technology, engineering and mathematics engagement and learning.

Shiga toxin-producing Escherichia coli (STEC) poses a significant public health risk due to its zoonotic potential and association with foodborne outbreaks. This study investigates the presence of STEC in faecal samples collected from sheep, focusing on bacteriological methods for isolation and preliminary characterization. Growth on selective agar showed that 90 of 140 faecal samples were positive for STEC. The total average prevalence was 64.3% (95% CI 56.1-71.7%). The highest prevalence was 71.4% (54.9-83.7%), recorded in summertime, while the lowest was 51.4% (35.6-67%) in the autumn. Selected isolates were found to be resistant to commonly used antibiotics, with isolates expressing a resistant phenotype to two, three or more of the tested antibiotics. Based on the Biocheck.UGent system for risk-based assessment of farm biosecurity, the total, internal and exterior average farm biosecurity scores were substantially lower than the world average.

Psoas abscess is a rare infection historically associated with tuberculosis (TB), although non-tuberculous bacterial causes, particularly Staphylococcus aureus, have become increasingly common. This type of abscess can be either primary or secondary, and its diagnosis remains challenging due to the non-specific nature of clinical signs. Imaging and microbiological analyses are essential for establishing the diagnosis. We report the case of a 22-year-old patient with no significant medical history, who presented with persistent mechanical low back pain for 18 months. Initial computed tomography revealed a non-compressive disc protrusion, leading to treatment with non-steroidal anti-inflammatory drugs, without improvement. Further investigations revealed an extrapulmonary spinal localization of TB in an immunocompetent patient, with bilateral psoas abscesses caused by Mycobacterium tuberculosis, confirmed by the Ziehl-Neelsen staining, auramine staining, culture on Löwenstein-Jensen medium and GeneXpert PCR. Anti-TB treatment was initiated, resulting in favourable clinical evolution.

Tuberculosis is a major scourge, posing a serious public health problem in countries where it is endemic. Osteoarticular involvement accounts for 3-5% of all tuberculosis cases and 10-15% of extrapulmonary tuberculosis cases. We report a case of tibial osteitis caused by Mycobacterium tuberculosis in a 52-year-old female patient who presented to the trauma department at the Mohammed V Military Teaching Hospital with a painful swelling of the lower part of her left leg. Standard X-rays and computed tomography scans revealed bone involvement, specifically in the tibia. Additional investigations revealed pulmonary consolidation and splenic nodules. Microscopy (Ziehl-Neelsen staining), GeneXpert MTB/RIF and histopathological examination all returned positive results for M. tuberculosis. In an endemic context, any persistent and atypical bone lesion should raise suspicion of osteoarticular tuberculosis to enable rapid diagnosis and appropriate therapeutic management. In the absence of malignant tumours and other differential diagnoses, the diagnosis of skeletal tuberculosis must be considered, even in the absence of specific clinical signs.

Staphylococcus argenteus (SARG) was discovered in 2009 as part of the Staphylococcus aureus (SAUR) complex and has been documented from various locations worldwide. In this article, we describe the genomic features of five strains of SARG found in Christchurch, New Zealand. Isolates were first detected in 2019 using MALDI-TOF identification, and their identities were confirmed using whole-genome sequencing. Genomic features, including antimicrobial resistance markers and virulence factors, were compared with other SARG sequences in the NCBI GenBank and well-characterized features in SAUR. Four isolates belonged to ST2250 and one isolate to ST2793. Phylogenetic analysis based on core genome analysis revealed that all five isolates were phylogenetically distinct, with four isolates clustering in the ST2250 clade. Three isolates contained staphylococcal cassette chromosome mec (SCCmec) type IV 2Bc, harbouring the mecA gene conferring resistance to beta-lactam antibiotics. All five strains shared many of the virulence genes found in the global SARG and SAUR isolates; however, no TSST-1 or PVL pathogenic genes were detected. This publication contributes additional data on global occurrences and genomic features of SARG.