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In settings with high tuberculosis (TB) endemicity, distinct genotypes of the Mycobacterium tuberculosis complex (MTBC) often differ in prevalence. However, the factors leading to these differences remain poorly understood. Here we studied the MTBC population in Dar es Salaam, Tanzania over a six-year period, using 1,082 unique patient-derived MTBC whole-genome sequences (WGS) and associated clinical data. We show that the TB epidemic in Dar es Salaam is dominated by multiple MTBC genotypes introduced to Tanzania from different parts of the world during the last 300 years. The most common MTBC genotypes deriving from these introductions exhibited differences in transmission rates and in the duration of the infectious period, but little differences in overall fitness, as measured by the effective reproductive number. Moreover, measures of disease severity and bacterial load indicated no differences in virulence between these genotypes during active TB. Instead, the combination of an early introduction and a high transmission rate accounted for the high prevalence of L3.1.1, the most dominant MTBC genotype in this setting. Yet, a longer co-existence with the host population did not always result in a higher transmission rate, suggesting that distinct life-history traits have evolved in the different MTBC genotypes. Taken together, our results point to bacterial factors as important determinants of the TB epidemic in Dar es Salaam.

The indispensable relationship between Research and Statistics makes the teaching of both courses crucial in all postgraduate programmes. However, over the years, postgraduate students have displayed a high level of anxiety in studying Statistics. Therefore, exploiting the descriptive case study strategy knitted within the sequential explanatory design, a Statistics teacher was studied in one of Ghana's outstanding universities and the reported pedagogical behaviours were profiled. Primary data were obtained from 99 postgraduate students (reading various postgraduate programmes on regular, sandwich and distance modes of education) on their level of anxiety in Statistics (using the Statistics Anxiety Rating Scale) and their experiences with their teacher's pedagogical behaviours. Also, 12 of the postgraduate students were interviewed about the pedagogical behaviours of their teacher that reduced their anxiety in Statistics. To triangulate the primary data, secondary results on the teacher's teaching practices were obtained from the Directorate of Academic Planning and Quality Assurance Unit of the university (originally gathered through a statistical academic support scale). Descriptive (mean and standard deviation) and inferential (one-way ANOVA and SEM) statistics were used to analyse the quantitative data and the qualitative data were analysed into themes. Consequently, the study found 17 teacher pedagogical behaviours under teacher characteristics (cognitive and affective factors) and pedagogical practices that reduced postgraduate students' statistical anxiety and heightened positive attitudes towards the study of Statistics. Therefore, a recognition of these pedagogical behaviours and their open display during the teaching of Statistics will go a long way in reducing postgraduate students' high statistical anxiety.

Revising teacher education frameworks and incorporating contemporary identified teacher attributes into the frameworks helps to ensure formidable initial teacher training. This paper validated teacher engagement efficacy for further consideration. Research findings that link preservice teachers' teaching self-efficacy to their instructional effectiveness were found to be contradictory, whilst others had validity issues with the measurement of instructional effectiveness variable. Thus, there is inadequate support for the inclusion of teaching self-efficacy in teacher education frameworks. Therefore, using objective measurement of instructional effectiveness, the current study utilised ex-post facto research design to predict preservice management teachers' instructional effectiveness based on their teaching self-efficacy. Secondary data were gathered on preservice teachers' teaching self-efficacy and instructional effectiveness; the dataset covered 119 cases. Empirical models were formulated to determine the nexus between preservice teachers' teaching self-efficacy and instructional effectiveness. Both descriptive (frequency and percentage) and inferential statistics (independent samples t-test, simple and multiple linear regressions) were used to analyse the data. Preservice management teachers' level of instructional effectiveness was very good, which was not influenced by their gender and their age. Significantly, their student engagement efficacy positively influenced their instructional effectiveness. Therefore, teacher educators might risk preservice teachers' instructional effectiveness should they (teacher educators) fail to develop their (preservice teachers) teaching engagement efficacy, with focus on behavioural, emotional and cognitive engagement.

Diarrheal disease remains a major global health problem particularly in children under 5 years and the emergence of antibiotic-resistant strains of causative pathogens could slow control efforts, particularly in settings where treatment options are limited. This surveillance study conducted in Ghana aimed to determine the prevalence and antimicrobial susceptibility profile of diarrhea-causing bacteria. This was a cross-sectional study carried out in five health facilities in the Ga West Municipality of Ghana between 2017 and 2021. Diarrheic stool samples from patients were collected and cultured on standard differential/selective media and isolates identified by standard biochemical tests, MALDI-TOF assay, and serological analysis. The antibiogram was determined using Kirby-Bauer disk diffusion and Microscan autoScan4 MIC panels which were used for extended-spectrum beta-lactamase (ESBL) detection. Bacteria were isolated from 97.5% (772/792) of stool samples, and 167 of the isolates were diarrheagenic and met our inclusion criteria for antimicrobial resistance (AMR) analysis. These included Escherichia coli (49.1%, 82/167), Salmonella species (23.9%, 40/167), Vibrio species (16.8%, 28/167), and Shigella species (10.2%, 17/167). Among 24 Vibrio species, we observed resistances to cefotaxime (21/24, 87.5%), ceftriaxone (20/24, 83.3%), and ciprofloxacin (6/24, 25%), including four multi-drug resistant isolates. All 13 Vibrio parahaemolyticus isolates were resistant to cefazolin. All 17 Shigella isolates were resistant to tetracycline with resistance to shigellosis drugs such as norfloxacin and ciprofloxacin. Salmonella isolates were highly susceptible to norfloxacin (40/40, 100%) and tetracycline (12/34, 35%). Two ESBL-producing E. coli were also identified with marked susceptibility to gentamicin (66/72, 91.7%) and amikacin (57/72, 79.2%) prescribed in the treatment of E. coli infections. This study showed the different bacteria implicated in diarrhea cases in Ghana and the need for differential diagnoses for better treatment outcomes. Escherichia coli, Shigella, Salmonella, and Vibrio have all been implicated in diarrhea cases in Ghana. The highest prevalence was E. coli and Salmonella with Shigella the least prevalent. Resistance to commonly used drugs found in these isolates may render bacteria infection treatment in the near future nearly impossible. Routine antimicrobial susceptibility testing, effective monitoring, and nationwide surveillance of AMR pathogens should be implemented to curb the increase of antimicrobial resistance in Ghana.

The emergence of SARS-CoV-2 variants with superior transmissibility or immune evasion advantages may cause outbreaks and dominate transmission in a population (1). Thus, keeping track of the dynamics of variant [...]

Background: Resistance to tuberculosis (TB) drugs has become a major threat to global control efforts. Early case detection and drug susceptibility profiling of the infecting bacteria are essential for appropriate case management. The objective of this study was to determine the drug susceptibility profiles of difficult-to-treat (DTT) TB patients in Ghana. Methods: Sputum samples obtained from DTT-TB cases from health facilities across Ghana were processed for rapid diagnosis and detection of drug resistance using the Genotype MTBDRplus and Genotype MTBDRsl.v2 from Hain Life science. Results: A total of 298 (90%) out of 331 sputum samples processed gave interpretable bands out of which 175 (58.7%) were resistant to at least one drug (ANYr); 16.8% (50/298) were isoniazid-mono-resistant (INHr), 16.8% (50/298) were rifampicin-mono-resistant (RIFr), and 25.2% (75/298) were MDR. 24 (13.7%) of the ANYr were additionally resistant to at least one second line drug: 7.4% (2 RIFr, 1 INHr, and 10 MDR samples) resistant to only FQs and 2.3% (2 RIFr, 1 INHr, and 1 MDR samples) resistant to AMG drugs kanamycin (KAN), amikacin (AMK), capreomycin (CAP), and viomycin (VIO). Additionally, there were 4.0% (5 RIFr and 2 MDR samples) resistant to both FQs and AMGs. 81 (65.6%) out of 125 INH-resistant samples including INHr and MDR had katG-mutations (MT) whereas 15 (12%) had inhApro-MT. The remaining 28 (22.4%) had both katG and inhA MT. All the 19 FQ-resistant samples were gyrA mutants whereas the 10 AMGs were rrs (3), eis (3) as well as rrs, and eis co-mutants (4). Except for the seven pre-XDR samples, no sample had eis MT. Conclusion: The detection of several pre-XDR TB cases in Ghana calls for intensified drug resistance surveillance and monitoring of TB patients to, respectively, ensure early diagnosis and treatment compliance. [ABSTRACT FROM AUTHOR]