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Fitness traits and genetic characterization of a new laboratory colony of Anopheles funestus established in Ifakara, Tanzania
(Nature and Springer, 2026-08-13) Hape, Emmanuel; Njalambaha, Rukiyah; Muyaga, Letus; Siria, Doreen; Nambunga, Ismail; Mgando, Joseph; Mwasheshi, Dickson; Nombo, Neema; Mabula, Daniel; Zengenene, Munyaradzi; Kahamba, Najat; Odero, Joel; Ngowo, Halfan; Mapua, Salum; Chaki, Prosper; Govella, Nicodem; Lyimo, Issa; Kiware, Samson; Lwetoijera, Dickson; Tarimo, Brian
Background: Anopheles funestus, a major vector of malaria in Africa, has proven difficult to colonize in laboratory settings, impeding research on its biology and control. After several attempts, our team recently succeeded in colonizing a strain of An. funestus from Tanzania (FUTAZ). The objective of this study was to analyse the key fitness and genotypic characteristics of these mosquitoes during multiple filial generations of laboratory adaptation and compare them to wild An. funestus from Tanzania and a pre-existing colony of An. funestus from Mozambique (FUMOZ). Methods: Measures of mating success, body size, fecundity, and insecticide resistance were compared between the newly established FUTAZ colonies, the long-established FUMOZ colonies, and a colony of Anopheles arabiensis maintained in the same laboratory. The maternal lineages of the An. funestus mosquitoes were investigated through a hydrolysis probe analysis of their mitochondrial DNA to identify distinct clades. Other intragenomic variations were examined by D3-RFLP genotyping of 28S ribosomal DNA. These molecular markers were used to compare the FUTAZ colonies, FUMOZ colonies in Tanzania (TZ) and South African (SA) laboratories, and the wild-collected Tanzanian An. funestus. Result: The mating success and body size of FUTAZ females declined significantly from filial generations F1 to F6 relative to the founder population (F0) then increased from F7 onwards eventually matching FUMOZ by F9. Fecundity was similar across all colonies tested. However, it took significantly longer for 50% of the females in the FUTAZ and FUMOZ colonies (>10 days) to mate compared to females in the An. arabiensis colony (~5 days). Resistance appeared to be lost during colonization, but this varied with insecticide classes. Majority of FUTAZ mosquitoes, and the wild-caught Tanzanian An. funestus belonged to Clade I (80.4-89.4%) and RFLP type “Y” (90.5-91.4%), while FUMOZ colonies in TZ and SA were mostly Clade II (65.5-88.5%) and RFLP type “MW” (90.5-91.5%). Conclusion: This study demonstrates that certain fitness traits of An. funestus, notably mating success and body size, declined during the initial phases of laboratory colonization but recovered as the population adapted to laboratory conditions. Having large founder populations is critical to survive these early-generation bottlenecks. Clade-specific and RFLP genotyping confirmed FUTAZ colony as
genetically representative of wild-caught Tanzanian An. funestus. This newly established colony constitutes a valuable and reliable resource for malaria vector research.
Development and Nutritional Evaluation of an Extruded Grain Amaranth-Instant Porridge as a supplementary food for Children Under Five with Moderate Acute Malnutrition.
(Taylor and Francis, 2026-08-12) Mwikwabe, Amos; Haikael, Martin; Mushi, Benson; Kejo, Dyness
Moderate acute malnutrition (MAM) among children under five remains a challenge in Tanzania, where the fortified blended foods used to manage it are almost entirely imported, expensive and inaccessible. This study developed and evaluated a grain amaranth-based extruded instant porridge as a locally sourced alternative. Five formulations were generated from grain amaranth, pro-vitamin A maize, soybean and sesame by two-stage linear programming using regional food composition data, with crude protein maximized subject to a technological fat ceiling of 11.0 g/100 g. Formulation 1, the least-cost solution, and Formulation 5, the most nutrient-dense within fat ceiling that is more economical than the non-compliant Formulation 3, were advanced to twin-screw extrusion. Proximate composition (AOAC 2005), mineral content (atomic absorption spectrophotometry) and anti-nutritional factors (colorimetric methods) were determined; functional and sensory properties were evaluated; data were analyzed by ANOVA. Protein ranged from 18.14 in formulation 1 to 20.53% in formulation 5, while energy density reached 391.93 kcal/100 g in formulation 5 reaching 98.0% of the WFP/UNICEF Super Cereal Plus (CSB++) minimum of 400 kcal/100 g. Formulation 5 showed the highest fat (11.95 g/100 g) and zinc (8.98 mg/100 g), all within CSB++ ranges, with only potassium below specification (37.1%). Extrusion significantly increased water absorption capacity (p < 0.001), shifted the flour from the fair to good flowing category, and reduced tannins, oxalates and phytate by 50.2%, 64.9% and 77.6% relative to raw grain amaranth. Sensory scores showed good overall acceptability (6.2–6.9), with significant differences for aroma (p < 0.001) and flavor (p = 0.002); SC(F5)-777 ranked highest among extruded samples. Food-to-food fortification using grain amaranth at 40–45% produced energy- and nutrient-dense instant porridge with improved mineral content, functional properties, and sensory characteristics, demonstrating strong potential for use as locally available supplementary food for managing MAM in children under five.
Prevalence and Factors Associated with HIV Infection Among Tuberculosis Patients aged below 15 years Across regions with High TB burden in Tanzania: A Six- year Retrospective Cross-Sectional Study
(Research square, 2026-08-12) Mgeyi, Evance; Kalabamu, Florence; Onduru, Onduru; Kisonga, Riziki; Balama, Robert; Sililo, Galus; Shimba, Paul; Kwesiga, John; Ainembabazi, Rose; Solomon, Wafula; Nsubuga, Deo; Kimuli, Derrick
Background
TB-HIV co-infection disproportionately affects children in sub-Saharan Africa. Scale-up of PMTCT, ART, and TB Preventive Therapy (TPT) aims to reduce this burden. This study estimated HIV prevalence among TB-registered children aged < 15 years across ten high-burden Tanzanian regions (2018–2023) and identified factors associated with HIV co-infection.
Methods
A cross-sectional retrospective review of records was conducted using secondary data extracted from the National TB and Leprosy System, District Health Information System-2 Electronic TB and Leprosy (DHIS2-eTL). All children aged < 15 years who were diagnosed with TB and had documented HIV status across ten regions with high a TB burden between January 2018 and December 2023 were included. Binary logistic regression was used to identify factors associated with HIV co-infection, and results are reported as adjusted odds ratios (aOR) with 95% confidence intervals (CI) at 5% statistical significance
Results
Among 25,449 children with TB, 3,667(14.4%) had a documented HIV-positive status. HIV prevalence declined markedly from 28.5% in 2018 to 8.9% in 2023 (p < 0.001). Pediatric TB-HIV co-infection increased with age: 9.0% in children aged below 5 years, 17.7% in those aged 5–9 years, and 22.6% in those aged 10–14 years (p < 0.001), with noticeable regional variations. After multivariable adjustment, older age groups (aOR = 2.32 95% CI 2.11–2.55 and 2.99 95% CI 2.72–3.29 for 5–9 and 10–14 years, respectively), residence in Njombe (aOR = 1.73, 95% CI 1.46–2.04), Mbeya (aOR = 1.53, 95% CI 1.31–1.78), and Iringa (aOR = 1.37, 95% CI 1.17–1.61), and a history of prior TB treatment (aOR: 3.75–4.68) were independently associated with higher odds of co-infection. The COVID-19 era (2020–2023) was associated with substantially lower odds of co-infection (aOR = 0.42, 95% CI 0.39–0.46).
Conclusions
HIV prevalence among children with TB in Tanzania declined from 28.5% to 8.9% between 2018 and 2023, temporally coinciding with scaled-up PMTCT, ART and TPT interventions, though this cross-sectional analysis cannot establish causality, the trend is consistent with programmatic success. However, persistent regional disparities, higher risk in older children, and a strong association with prior TB treatment underscore ongoing vulnerabilities that may require more nuanced attention.
Antibody lectin chimeras targeting glycan shields to overcome tumor immune evasion
(Springer and Nature, 2026-08-07) Mehmood, Muhammad; Büyükkılıç, Şehriban; Amos, Yohana; Wajid, Taimoor; Hasnain, Syeda; Ullah, Hikmat; Kamal, Mohammad; Ali, Faizan; Nazari, Mohammad
Tumor immune evasion remains one of the most persistent obstacles in cancer therapy. A key driver is aberrant glycosylation, a near-universal feature of malignant transformation that reshapes the tumor surface into a dense, immunosuppressive glycan shield. Hypersialylation, truncated O-glycans, and other tumor-associated carbohydrate antigens engage inhibitory receptors such as Siglec-7 and Siglec-9 on natural killer cells and macrophages, silencing innate immune surveillance. These glycan alterations also stabilize immune checkpoints, including PD-L1, and shield tumor antigens like HER2 and MUC1 from antibody recognition, limiting the effectiveness of conventional immunotherapies. Antibody-lectin chimeras (AbLecs) offer a structurally elegant solution. By fusing a tumor-targeting antibody, such as a HER2-directed IgG1, with a lectin-Fc decoy domain, AbLecs achieve dual recognition of protein antigens and hypersialylated glycan patterns simultaneously. This bivalently structured architecture increases avidity, physically excludes inhibitory Siglec receptors from the immunological synapse, and restores antibody-dependent cellular cytotoxicity and phagocytosis. Preclinical studies show that HER2-directed AbLecs outperform trastuzumab in reducing tumor burden and lung metastases in humanized Siglec mouse models, with limited off-tumor reactivity due to the weak baseline affinity of the lectin domain. This review covers tumor glycobiology, lectin biology, AbLec engineering, and antitumor mechanisms. Key challenges, including glycan heterogeneity, manufacturing complexity, and off-tumor toxicity, are discussed alongside glycomic biomarker strategies and combination regimens. AbLecs represent a meaningful advance in glyco-immunotherapy, turning the tumor glycocalyx from a protective shield into a viable therapeutic target.
Multi-centre laboratory study to determine discriminating concentrations for broflanilide and isocycloseram resistance monitoring in mosquitoes
(Frontiers, 2026-08-11) Praulins, Giorgio; Mechan, Frank; Harvey, Gemma; Brooke, Basil; Corbel, Vincent; Duchon, Stephane; Kaiser, Maria; Moore, Sarah; Mpelepele, Ahmadi; Oliver, Shüne´; Singh, Himmat; Stevenson, Jennifer; Toguem, Yvan; Verma, Vaishali; Wondji, Charles; Lees, Rosemary
Introduction: Discriminating concentrations (DCs) underpin routine monitoring of insecticide susceptibility, but none had been established for broflanilide or isocycloseram, two new active ingredients entering vector control. This study aimed to establish and validate DCs in WHO bottle bioassays for monitoring susceptibility to broflanilide and isocycloseram in Anopheles gambiae s.s., An. funestus, An. stephensi, and Aedes aegypti.
Methods: In 2024–2025, a multi-centre study involving seven international laboratories was conducted with the support of the World Health Organization (WHO), applying the generic WHO protocol for establishing discriminating concentrations to susceptible reference strains of each species.
Results: The following values are recommended for adoption as DCs for broflanilide: 10 μg/bottle for An. gambiae and Ae. aegypti, 15 μg/bottle for An. funestus, and 25 μg/bottle for An. stephensi. The recommended DCs for isocycloseram are 15 μg/bottle for Ae. aegypti, 30 μg/bottle for An. gambiae, 50 μg/bottle for An. stephensi, and 60 μg/bottle for An. funestus.
Discussion: Based on the experience gained from conducting this study, technical recommendations are made to support the generation and analysis of DC data for insecticides in the future.