Baobab Index

Lassa virus (LASV) causes severe hemorrhagic fever across West Africa where the development of rapid, accurate diagnostics remains hindered by the extensive lineage-level genetic diversity and by the limited availability of high-level containment laboratories. We developed a LASV assay using the CRISPR-based Streamlined Highlighting of Infections to Navigate Epidemics (SHINE) platform to enable safe, field-deployable detection. To enable assay development without handling live virus, we established a plasmid-based system that generates LASV RNA controls spanning major viral lineages. Using these surrogate plasmids, we optimized the assay for 32 genetically distinct LASV isolates, demonstrating detection across major lineage subdivisions with lineage-dependent sensitivity. The assay maintained sensitivity in serum and whole blood, and was further evaluated using clinical samples in Nigeria. To reduce subjectivity in strip interpretation, we developed supervised machine-learning models for automated classification of lateral flow results. Together, this integrated diagnostic framework supports field-oriented detection of genetically diverse LASV and provides a broader approach for diagnostic development for high-consequence RNA viruses.

Mercury is a ubiquitous environmental pollutant that interferes with neurological and reproductive functions through oxidative stress, inflammation, and genomic instability. Although mild heat stress can induce hormesis to combat environmental insults, the ability of heat stress to ameliorate heavy-metal-induced toxicity and the importance of exposure duration remain poorly defined. This study investigated whether short-term thermal stress modulates mercuric chloride (HgCl₂) toxicity in D. melanogaster. Adult flies were exposed to HgCl₂ (10 mM) alone or concurrently with mild heat stress (37 °C) for 5 or 15 min. Survival, locomotor performance, reproductive fitness, redox homeostasis, membrane ATPase activities, nitric oxide levels, dopamine content, DNA fragmentation, and brain histoarchitecture were assessed. HgCl₂ exposure significantly reduced survival, locomotor activity, fecundity, antioxidant capacity, ATPase activities, and dopamine levels, while increasing oxidative stress markers, nitric oxide production, DNA fragmentation, and neurodegenerative changes in the brain. Co-exposure to 5 min of heat stress markedly attenuated HgCl₂-induced toxicity, improving survival, neuromuscular performance, reproductive output, redox balance, dopamine levels, and brain cytoarchitecture. In contrast, 15 min of heat stress provided limited attenuation and, when applied independently, induced mild toxicity at several endpoints. Protective effects were accompanied by partial restoration of thiol status, suppression of xanthine oxidase activity, normalisation of nitric oxide levels, preservation of Na⁺/K⁺- and Ca

Emerging infectious diseases are a hallmark of the Anthropocene

Hybridization between domestic and wild species is an increasing conservation concern, as continued introgression could lead to genomic extinction. The Endangered Ethiopian wolf (Canis simensis) is thought to be threatened by hybridization with free-roaming domestic dogs (C. familiaris) and African golden wolves (C. lupaster), particularly in human-dominated landscapes. Phenotype-based assessments during two field seasons in 1989 and 1991 have suggested that 8-17% of individuals in the Bale Mountains show signs of admixture, but the extent and timing of gene flow remain unresolved. This study analyzed 27 whole genomes, including nine Ethiopian wolves that showed no obvious signs of admixture, collected in 2003, to quantify patterns of introgression among African canids. Population structure analyses identified limited signals of hybridization, with most Ethiopian wolves forming a distinct genetic cluster. Although two related Ethiopian wolves exhibited subtle but significant excess allele sharing with African golden wolves, the overall genomic data provide little support for strong recent or directional introgression. Linkage disequilibrium decay analyses suggest an admixture event occurring approximately 800 generations ago; however, estimates of timing and admixture proportion were not robust, indicating substantial uncertainty in the precise parameters. Forward-in-time simulations indicate that, despite currently limited introgression, continued small population sizes could facilitate gradual genomic replacement over evolutionary timescales. Therefore, hybridization may become increasingly important under sustained demographic decline.

Escherichia coli O157: H7 is a globally important zoonotic pathogen responsible for the majority of severe cases of human enterohemorrhagic Escherichia coli (EHEC) disease. The transmission of this pathogen is exacerbated in Ethiopia due to the common habit of consuming raw and/or undercooked meat. This study was conducted to isolate E. coli O157:H7, detect virulence genes, and assess the antimicrobial susceptibility patterns of isolates recovered from ready-to-eat raw meat (kurt) sold in Bahir Dar City, Ethiopia. A cross-sectional study design with a simple random sampling technique was employed to collect questionnaire data and raw meat samples from butcher houses. A total of 74 meat samples were collected and processed using standard microbiological methods, and genomic DNA from positive isolates was analyzed by polymerase chain reaction (PCR). All data collected during the study period were coded and entered into an Excel spreadsheet and analyzed using STATA version 12. Of the 74 examined samples, E. coli O157:H7 was detected in 21 (28.4%). Out of 21 isolates, 10 (47.6%) carried at least one of the investigated virulence genes, with detection rates of 100% for the stx1 and 70% for the eaeA genes. Only 16.2% of meat handlers had received training on safe food handling. Lack of training was associated with higher odds of E. coli O157:H7 contamination (AOR = 0.16, p = 0.028). The presence of E. coli O157:H7 was also significantly associated with the practice of workers collecting money from the customers while cutting meat (AOR [95% CI] = 3.7 [1.01-11.48]). Antibiotic profiling showed that the resistance rate ranged from 4.8% to 33.3%. About six (28.6%) isolates were resistant to two antimicrobial agents, amoxicillin and chloramphenicol. The detection of E. coli O157:H7 in nearly one-third of the samples and the occurrence of virulence genes in half of the isolates indicate the potential risk of foodborne infection in the study area. Therefore, food safety awareness and training for meat handlers should be encouraged to reduce the spread of this pathogen in Bahir Dar City.

The hypothesis that A total of 772 milk samples were collected and analysed sequentially using two molecular assays targeting the MAP DNA was confirmed by nested PCR and subsequent sequencing in 2.3% of the samples, with equal frequencies in pasteurized and unpasteurized milk. Additionally, one raw milk sample demonstrated viable MAP growth by culture. The findings of contamination of commercial milk with MAP in the Uganda's Capital aligns with the reported prevalence of cattle paratuberculosis in the country and underscore the need for rigorous protocols for preparation of milk and dairy products to reduce contaminating viable pathogenic bacteria including MAP. Consequently, more efforts toward control of paratuberculosis in livestock are required to mitigate possible public health risks through foodborne pathogens.

The consumption of whole wheat has increased due to its nutritional benefits, particularly its richness in phenolic compounds. This study evaluated the influence of the farming systems (organic and conventional) and the diversity of thirteen Tunisian durum wheat varieties (landraces and modern genotypes) on the phenolic profile and antioxidant capacity. UHPLC-MS

Primary bile acid synthesis defects (BASD) are autosomal recessive disorders causing cholestatic liver disease and fat-soluble vitamin malabsorption. Despite being treatable with cholic acid (CA), BASD remain underdiagnosed, particularly in resource-limited settings. No data have been published from Tunisia. A retrospective study of all patients diagnosed with BASD at La Rabta University Hospital in Tunis, between 2013 and 2024 described clinical presentation, biochemical and genetic findings, treatment and outcomes. Six male patients from three unrelated families were enrolled. The age at symptom onset ranged from the neonatal period to 8 years, with a diagnostic delay spanning from 1.5 months to 5 years. Three distinct phenotypes were observed: cholestasis (3/6), malabsorption (4/6), and non-cholestatic hepatopathy (1/6). Four patients presented with 3β-hydroxysteroid dehydrogenase deficiency, including three siblings homozygous for a novel This first Tunisian small series highlights the phenotypic heterogeneity of BASD, even in the same family, and the efficacy of CA therapy when initiated early. Besides low GGT cholestasis, fat-soluble vitamin malabsorption and non-cholestatic liver phenotype require investigation of serum bile acids as well as bile acids in urine. Improved access to specialized diagnostic tools and orphan drug therapies is urgently needed in resource-limited settings.

This international Consensus Statement updates 2016 guidelines for diagnosis and management of individuals with Silver-Russell syndrome (SRS), using a Delphi-like process to reach agreement through iterative expert discussions, based on published data and/or expert opinion. Individuals referred with suspected SRS show substantial clinical and genetic heterogeneity. Advances in genomic and epigenomic technology highlight the need for strict, primarily molecular, criteria for diagnosis, which should be made in those with maternal uniparental disomy for chromosome 7 (upd(7)mat) or 11p15 loss of methylation at H19/IGF2:intergenic differentially methylated region (IG-DMR) (due to an imprinting change, copy number variant or upd(11)mat). Molecular stratification enables tailoring of care pathways towards specific genetic and/or epigenetic subgroups. More widely, recommendations are relevant to other growth-related imprinting disorders (including Temple syndrome) and conditions affecting the insulin-like growth factor 2 pathway. An expert, multidisciplinary approach is required, focusing on growth failure, early severe feeding difficulties, later possible rapid weight gain, abnormal body composition, gastrointestinal problems, hypoglycaemia, insulin resistance, accelerated puberty, body asymmetry, neurocognitive issues and psychosocial challenges. Evidence published since the first Consensus Statement highlights the increased risk of metabolic disease from adolescence into adulthood. These updated recommendations have important implications for accurate diagnosis and optimal life-long management of individuals with SRS.