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Non-symbiotic Bradyrhizobium are among the most abundant and ubiquitous microbes in bulk soils globally. Despite this, most available genomic resources for Bradyrhizobium are derived from plant-associated strains. We present high-quality draft genomes for 17 Bradyrhizobium and four Nitrobacteraceae cultures isolated from bulk semiarid soils in Arizona, USA. The genome sizes range from 5.99 to 10.4 Mbp. Phylogenomic analysis of the 21 genomes indicates they fall into four clades. Two of the clades are nested within the Bradyrhizobium genus. The other two clades were associated with Nitrobacteraceae outgroups basal to Bradyrhizobium. All genomes lack genes coding for molybdenum or vanadium nitrogenases, and nod genes that code for proteins involved in nodulation, suggesting these isolates are free-living, non-symbiotic and do not fix dinitrogen gas. These genomes offer new resources for investigating free-living Bradyrhizobium lineages.

Teaching the complex interactions between hosts and pathogens is a fundamental yet educationally challenging aspect of life science and healthcare education. The intricate mechanisms of the immune system can pose significant barriers to students' understanding of infectious disease diagnosis and treatment. To address this, we used a web-based digital whiteboard platform to design a card-based competitive game called Micro-Immune Battles, aimed at more actively engaging students with microbiology and immunology to better develop their knowledge and underlying concepts. The game facilitates learning through a series of infectious disease scenarios, providing student teams with 'immune system response cards' that represent various immune elements. Working in teams, learners must construct sequential card cascades that correctly correspond to the specified pathogen in the scenario. This reinforces the temporal progression of immune responses whilst encouraging the application of theoretical knowledge to practical cases. Scoring is determined by the accuracy and speed of card placements, incentivizing rapid yet correct synthesis of knowledge. Points are deducted for incorrect placements, introducing an element of calculated risk-taking and critical reasoning. Analysis showed statistically significant improvements in microbiology and immunology knowledge after playing the game.

Comparing the diversity of gut microbiota between and within social insect colonies can illustrate interactions between bacterial community composition and host behaviour. In many eusocial insect species, different workers exhibit different task behaviours. Evidence of compositional differences between core microbiota in different worker types could suggest a microbial association with the division of labour among workers. Here, we present the core microbiota of Aphaenogaster picea ant workers with different task behaviours. The genus Aphaenogaster is abundant worldwide, yet the associated microbiota of this group is unstudied. Bacterial communities from Aphaenogaster picea gut samples in this study consist of 19 phyla, dominated by Proteobacteria, Cyanobacteria and Firmicutes. Analysis of 16S rRNA gene sequences reveals distinct similarity clustering of Aphaenogaster picea gut bacterial communities in workers that have more interactions with the refuse piles. Though gut bacterial communities of nurse and foraging ants are similar in overall composition and structure, the worker groups differ in relative abundances of dominant taxa. Gut bacterial communities from ants that have more interactions with refuse piles are dominated by amplicon sequence variants associated with Entomoplasmataceae. Interaction with faecal matter via refuse piles seems to have the greatest impact on microbial taxa distribution, and this effect appears to be independent of worker type. This is the first report surveying the gut microbiome community composition of Aphaenogaster ants.

Coronavirus disease 2019 (COVID-19) pandemic has been prevailing for more than a year, associated with an increased number of opportunistic invasive fungal infections in patients who have been critically ill or immunocompromised. In this retrospective study, details of various clinical specimens received from suspected patients of fungal infections were studied. Fungal cultures were positive in 64% (51 out of 79) of COVID-19-positive patients and 43% (163 out of 381) of COVID-19-negative patients during the second wave of COVID-19 in 2021. Among COVID-19-infected patients, the most commonly isolated fungi were Candida spp. (63%), followed by Aspergillus spp. (15%) and Mucor spp. (6%). The majority of samples that tested positive in COVID-19-infected patients were urine (17% from COVID-19-positive and 83% from COVID-19-negative patients), followed by serum (tested for Aspergillus galactomannan). Candida isolation was observed in 27% (21/79) of urine samples and 15% (12/79) of respiratory samples [bronchoalveolar lavage (BAL), tracheal aspirate, and sputum] from COVID-19-positive patients. Rhizopus arrhizus and Rhizopus homothallicus were isolated from nasal and tissue samples in 6% of COVID-19-positive patients. There was an overall increase in fungal co-isolations during the COVID-19 pandemic (64% in COVID-19-positive and 43% in COVID-19-negative patients), which is a matter of great concern. The correlation of clinical symptomatology and laboratory isolation is important for the diagnosis and effective management of these patients.

Bacterial urinary tract infections (UTIs) are common, ranging from benign cystitis to complicated pyelonephritis, which can lead to severe complications such as pyonephrosis and sepsis. Pyonephrosis, characterized by the presence of pus in the renal cavities, often requires urgent urological intervention. We report a unique case of pyonephrosis with a psoas abscess caused by Klebsiella pneumoniae and Peribacillus simplex in a 64-year-old diabetic female patient. This is the first case of pyonephrosis caused by P. simplex. The patient presented with acute right lumbar pain, fever and altered consciousness. Imaging revealed severe right hydronephrosis, pyonephrosis and a perirenal phlegmon infiltrating the psoas with abscesses. Surgical drainage and nephrectomy were performed. Microbiological and proteomic analyses identified K. pneumoniae and P. simplex. This case highlights the importance of considering environmental bacteria like P. simplex in severe infections and ensuring rigorous protocols to avoid contamination. Successful management of pyonephrosis relies on prompt surgical drainage and appropriate antibiotic therapy based on culture results.

Introduction. Comparative immunogenicity from different mRNA booster vaccines (directed at WT, BA.1 or BA.4/5 antigens) remains unclear. Methods. We included blood samples from adult paramedics who received three mRNA WT-directed vaccines plus a fourth dose of the following: (1) WT monovalent, (2) Moderna BA.1-WT bivalent or (3) Pfizer BA.4/5 WT bivalent vaccine. The primary outcome was angiotensin-converting enzyme 2 (ACE2) inhibition to BA.4/5 antigen. We used optimal pair matching (using age, sex-at-birth, preceding SARS-CoV-2 infection and fourth vaccine-to-blood collection interval) to create balanced groups to individually compare each vaccine type to each other vaccine (overall, within subgroups defined by SARS-CoV-2 infection and after combining BA.1 and BA.4/5 cases). We compared outcomes with the Wilcoxon matched-pairs signed rank test. Results. Overall, 158 paramedics (mean age 45 years) were included. ACE2 inhibition was higher for BA.1 compared to WT (P=0.002); however, no difference was detected between BA.4/5 vs. WT or BA.1 vs. BA.4/5. Among cases with preceding SARS-CoV-2, there were no detected between-group differences. Among cases without preceding SARS-CoV-2, the only detected difference was BA.1>WT (P=0.003). BA.1 and BA.4/5 cases combined had higher ACE2 inhibition than WT (P=0.003). Conclusion. Omicron-directed vaccines appear to improve Omicron-specific immunogenicity; however, this appears limited to SARS-CoV-2-naive individuals.

Antiseptics have been used for infection control against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Ethanol (EtOH) was found to be effective against SARS-CoV-2, while chlorhexidine gluconate (CHG) was less effective. Therefore, virucidal activity may differ between different classes of antiseptic agents. In this study, the efficacy of antiseptics against SARS-CoV-2 was evaluated, and effective agents for infection control were identified. The following antiseptics were used in this study: 1.5% olanexidine gluconate (OLG); 80% EtOH; 1% sodium hypochlorite (NaClO); 0.2% benzalkonium chloride (BKC); 1% povidone-iodine (PVP-I); 0.5%, 1% and 1.5% CHG; and 0.5% alkyldiaminoethylglycine hydrochloride (AEG). The virucidal activity was evaluated at 0, 0.5, 1, 2 and 3 min according to EN14476. After 0.5 min of exposure, 1.5% OLG, 80% EtOH, 1% NaClO, 0.2% BKC and 1% PVP-I inactivated SARS-CoV-2 below the detection limit. The virus survived in the presence of 0.5% CHG, 1% CHG or 0.5% AEG for 3 min. The virucidal activity of 1.5% CHG was insufficient after 0.5 min of exposure. The results showed that virucidal activity against SARS-CoV-2 differs depending on the class of antiseptic agents used under clean conditions. Despite belonging to the same class of biguanide antiseptics, OLG was more effective against SARS-CoV-2 than CHG.

Introduction. A better understanding of knowledge, attitude and practices of undergraduate medical students towards antimicrobial resistance (AMR) is necessary to identify gaps in the current training curriculum. Methods. A 20-point Likert scale-based questionnaire divided into three parts, knowledge, attitude and practices, relating to antibiotic use and resistance was devised. Students attending each year of the undergraduate medical programme were approached to participate in the study over a 1-week period. Knowledge, Attitude and Practices scores of each year were compared through logistic ordinal regression and the Kruskal-Wallis (KW) test. Results. Two hundred and eight students participated in the study. Overall, knowledge of about intended use of antibiotics, fixed drug combinations and awareness about AMR was good (average score of 73.75%). Steady improvement in knowledge scores was observed from the first year (-0.441) to the final year (0.00). The medical students had favourable attitude towards rational antimicrobial use (Likert score ≥4), including the need to spread awareness about AMR amongst students and the public and following doctor's prescriptions. Self-medication was reported by 28.4% of students and hoarding of leftover doses by 49.1%. Attitude score had a direct correlation with the knowledge score on the KW test (χ ²=29.6, P≤0.5) but had no significant correlation with antimicrobial practices (χ ²=3.9, P≥0.5). The gaps identified in students' practices included self-medication, skipping of dosing and hoarding of leftover medication. Conclusion. As improvement in knowledge did not correlate with better personal behaviours regarding antibiotics, the current curriculum needs to include AMR as a focus area to ensure good antibiotic prescribing practices in future practitioners.

To date, data on animal enteroviruses (EVs) are scarce, especially in Central Africa. The aim of this study was to characterize EVs among pigs and goats in Cameroon and the Central African Republic (CAR). A total of 226 pig and goat faecal samples collected in two previous studies carried out in Cameroon and CAR were pooled and screened with molecular assays targeting EV-Es, EV-Fs and EV-Gs. EV genomes were amplified by RT-PCR and their sequences were obtained by Illumina sequencing and de novo assembly. Based on the capsid sequences, 27 EV-G sequences were identified and assigned to 11 virus types, while no EV-E or EV-F was observed. Phylogenetic analysis revealed that the EV-Gs detected in Central Africa do not form specific clusters compared to EV-Gs previously reported in other continents. This suggests a worldwide circulation of EV-Gs, which is likely due to the massive international trade of live animals. One human EV, EV-C99, which belongs to the species Enterovirus C, was detected in pigs. This is the third detection of such an event in a similar context, reinforcing the hypothesis that some EV-Cs could be infecting pigs. Our work provides new data on the genetic diversity of EVs circulating among domestic animals in Central Africa.

Introduction. Proper identification and management of post-kala-azar dermal leishmaniasis (PKDL) and canine leishmaniasis (CanL) cases are among the prerequisites to the effective control of visceral leishmaniasis worldwide. Unlike PKDL, CanL still awaits effective improvement because of its cryptic nature, absence of Leishmania parasites in lesions or lymph nodes and not complete sensitivity of some diagnostic tools in use. Because of the need for certain skills and equipment, both the liquid direct agglutination test and freeze-dried direct agglutination test (FD-DAT) versions are, in comparison with the indirect immunofluorescence antibody test (IFAT) or enzyme-linked immunosorbent assay (ELISA), practical and feasible diagnostic alternatives. Aim. Validate the performance of an improved FD-DAT to suit routine and large-scale applications in CanL endemic areas. Methodology. Introducing citrate-saline formaldehyde (CSF) as an anti-clumping agent to replace normal saline for antigen reconstitution and drastically, however, eligibly lower the concentration of promastigotes (1.4×10⁷) in comparison with the original FD-DAT reference (>5×10⁷ ml^-1). To ensure optimal safety, β-mercaptoethanol was replaced by urea or SDS as a serum-reducing agent. Results. By improving the procedure for reconstitution of FD-DAT antigen with CSF, a 150% reduction in the test application cost was achieved. Expired test batches (±4 years earlier) were successfully revitalized to full validity. As compared to the 48 h shelf-life time for the original, an FD-DAT batch reconstituted here with CSF maintained stability for ±12 months. Conclusions. The highly concordant results with IFAT and ELISA (one-way ANOVA test, P=0.142, homogeneity of variances P=0.009) as routine CanL diagnostics further motivate the application of the improved FD-DAT for the detection of the disease in endemic areas.