Abstract Background Early HIV diagnosis allows timely interventions to control HIV transmission. We have determined the proportion of recent infections among people living with HIV (PLHIV) enrolling to care in Ethiopia and identified factors associated with recent infection. Methods Participants (aged ≥ 15 years) newly enrolled in HIV care were recruited from urban clinics in central Ethiopia (2022–2024). We used a recent infection testing algorithm, combining limiting antigen avidity serology and viral load quantification, to determine HIV infection recency. Factors associated with recent infection were investigated using logistic regression analysis, including sex-stratified analyses. Results Among 622 participants (median age 35 years; 364 [58.5%] women), 42 (6.8%) had recent infection. Recent infection was more common among PLHIV aged 15–24 years compared to those > 24 years (adjusted odds ratio [aOR], 4.3; 95% confidence interval [CI], 2.1–8.6), and in PLHIV belonging to key and priority populations (aOR, 2.2; 95% CI, 1.1–4.2). In sex-stratified analyses, age 15–24 years remained significantly associated with recent infection in both men (unadjusted odds ratio, 6.4; 95% CI, 1.5–26.5) and women (aOR, 2.7; 95% CI,1.2–6.1), whereas belonging to key and priority populations was significantly associated with recent infection only among women (aOR, 2.4; 95% CI, 1.1–5.2). Conclusion A low proportion of PLHIV newly enrolled in care had recently acquired HIV infection. Recent infection was more common among persons aged 15–24 years and women belonging to key and priority populations. Further scale-up of HIV testing services are needed to improve detection of recent infection, which could help in prevention of new infections.
Pharmaceutical pollution is a growing environmental and public health issue in East Africa. It is fueled by rapid population growth, increased pharmaceutical consumption, insufficient wastewater treatment, and pharmaceutical uses. Leftover pharmaceuticals enter into water and land ecosystems through human and animal waste, hospital and industry discharges, and inadequate waste management practices. These pollutants present ecological dangers and significantly contribute to the rise and spread of antimicrobial resistance (AMR), posing a threat to both the environment and public health. This narrative review takes a One Health approach to explore pharmaceutical pollution, AMR, and regulatory responses in East Africa. The literature search was conducted between January 04, 2025, and July 25, 2025, using PubMed, Google Scholar, and grey literature. Evidence shows widespread contamination of water bodies, sediments, wastewater, and food products with antibiotics such as ciprofloxacin, sulfamethoxazole, and tetracyclines, often surpassing safety thresholds. Risk Quotient (RQ) analysis revealed significant environmental risks in Ethiopia (ciprofloxacin RQ = 8.58), Kenya (ciprofloxacin RQ = 3.5–40.6; sulfamethoxazole RQ = 0.1–3.53), and Uganda (RQ > 1). However, no RQ data is available in Tanzania, Sudan, South Sudan, Eritrea, Djibouti, Somalia, Rwanda, and Burundi. Furthermore, environmental samples through the regions consistently show the presence of AMR resistance genes, strongly linked through pharmaceutical contamination to the emergence of resistance. The review underlines the importance of ecopharmacovigilance (EVP), a developing field that focuses on monitoring and mitigating the environmental impacts of pharmaceuticals. Despite the development of national action plans on AMR and environmental protection policies in East African countries, implementation remains weak due to enforcement limitations, fragmented surveillance systems, inadequate wastewater treatment infrastructure, and low public awareness. This review emphasizes the immediate necessity of executing EVP within a One Health framework via augmented environmental surveillance, stringent regulatory enforcement, enhancements in wastewater treatment, green pharmacy initiatives, and geospatial monitoring. Furthermore, establishing a regionally harmonized EVP system supported by evidence is critical for addressing pharmaceutical pollution, combating AMR, safeguarding ecosystems, and promoting public health in East Africa.
Rapid and accurate detection of Salmonella is essential for improving food safety and reducing the burden of enteric infections, especially in low-resource settings. Aptamer-based diagnostic platforms offer a promising alternative to antibody-based methods, given their high specificity, stability, and low production cost. A DNA aptamer targeting Salmonella enterica was developed through Systematic Evolution of Ligands by Exponential Enrichment (SELEX) iterative rounds of selection. Target-binding efficiency was monitored by colorimetric and spectrophotometric binding tests. Silver nanoparticles (AgNPs) were synthesized and conjugated with candidate aptamers through direct adsorption. Dot blot colorimetric assays were performed by exposing aptamer-AgNP complexes to serial dilutions of Salmonella cultures ranging from 10² to 10⁸ CFU/mL. Aggregation was evaluated visually on nitrocellulose membranes and quantified by a UV-Vis spectrophotometer based on absorbance intensity and peak wavelength shifts. Controls included AgNPs alone and related non-target bacterial (Escherichia coli). Final aptamer pools were sequenced using Nextseq 550 Illumina platform to determine specific sequences and predict candidate secondary structures for future mass production. Aptamer selection showed progressive enrichment, with significant dot blot signal and aggregation from round 8, and strong binding after 12 rounds of SELEX. Upon exposure to Salmonella, aptamer-AgNP complexes exhibited a concentration-dependent aggregation response, with visual detection observed at bacterial concentrations of 105 CFU/mL and selective binding toward Salmonella compared to E. coli and spectrophotometrically quantifiable from 10⁵ CFU/mL. Peak absorbance increased from 0.31 AU for 10² CFU/mL target concentration to 1.73 AU with 10⁸ CFU/mL, and the wavelength shifted from 504 nm to 525 nm, indicating nanoparticle aggregation. No specific aggregation or spectral shifts were observed in control samples. The enriched aptamer candidates were identified and prioritized, exhibiting conserved secondary structures, including hairpins, multi-branched loops, and internal bulges, predicting to facilitate specific interactions with Salmonella outer membrane proteins or LPS-O antigen. This study demonstrates the diagnostic applicability of aptamer conjugated with AgNP colorimetric assays for sensitive and specific detection of Salmonella. Future work should focus on sequence-based chemical modifications to enhance aptamer immobilization and assay performance, thereby facilitating adaptation of the platform to lateral flow formats during mass production for point-of-care applications. IMPORTANCE:This study addresses a critical need for rapid, low-cost, and sensitive diagnostic tools for Salmonella detection, particularly in low-resource settings where conventional methods are often inaccessible or time-consuming. By developing an aptamer-based colorimetric assay using silver nanoparticles, the research offers a highly specific, sensitive, and affordable alternative to existing diagnostics. The use of DNA aptamers selected through Systematic Evolution of Ligands by Exponential Enrichment enables precise recognition of Salmonella surface markers, while the colorimetric readout allows for easy visual detection without the need for sophisticated instruments. The assay's sensitivity demonstrates its practical utility for early and field-level pathogen detection. Importantly, the incorporation of next-generation sequencing in aptamer characterization enhances the molecular understanding of aptamer-target interactions and supports future assay refinement for application in lateral flow assay. The findings support translating the platform into point-of-care formats, which help food safety monitoring and infectious disease control in developing regions.
The 8-aminoquinoline antimalarials are used to prevent P. vivax relapses. Recent evidence suggests high total dose primaquine (7 mg/kg) provides optimal efficacy, however, many countries, including Ethiopia, use low total dose primaquine (3.5 mg/kg). To understand the risks and benefits of different primaquine dosing regimens for P. vivax malaria in Ethiopia, we undertook a systematic review and individual patient data meta-analysis. We searched for antimalarial efficacy studies in patients with uncomplicated P. vivax mono-infections conducted in Ethiopia, published between January 1, 2000, and March 8, 2024. Studies were included if they had at least 28 days of follow-up and included a treatment arm with daily primaquine, commenced within seven days of starting antimalarial treatment. Study investigators were approached to share individual patient data, which were standardised and pooled. We performed a one-stage meta-analysis to estimate the cumulative incidence of P. vivax recurrence by day 180 with different primaquine total dose regimens. The number and proportion of gastrointestinal symptoms on days 5–7 and clinically significant haemolysis within 14 days were described and stratified by daily primaquine dose. PROSPERO CRD42023491851. Of 297 identified studies, 5 were eligible for inclusion. Data from 1,378 patients from all 5 studies were obtained. The cumulative incidence of P. vivax recurrence by day 180 was 61.0
