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Regional trends in childhood tuberculosis case notification and treatment outcomes: Tanzania, 2018–2023
(Elsevier Ltd., 2026-07-30) Mgeyi, Evance; Kalabamu, Florence; Onduru, Onduru; Riziki, Kisonga; Balama, Robert; Sililo, Galus; Shimba, Paul; Kwesiga, John; Rose, Ainembabazi; Wafula, Solomon; Nsubuga, Deo; Kimuli, Derrick
Background
Globally, one-in-two childhood tuberculosis (TB) case remains undiagnosed, and TB remains a leading cause of death among children under 15 years despite favorable treatment outcomes. This study assessed trends in case notification and outcomes among children with TB across ten regions of Tanzania.
Methods
We conducted a retrospective cross-sectional study using data from Tanzania's national electronic TB and Leprosy System for children diagnosed between 2018 and 2023. Mann-Kendall Tests were used to assess the existence of monotonic trends in TB notifications, and distribution of outcomes was analyzed using Wilcoxon rank-sum test or Pearson's Chi-squared test, and binary logistic regression at a 5% significance level.
Results
25,449 childhood TB cases were notified over six-year period, with 14.4% (n = 3667) HIV/TB co-infected. Case notifications increased from 2688 in 2018 to a peak of 5421 in 2022 then declined to 4493 in 2023 (p = 0.047). Significant differences in unfavorable treatment outcomes were observed between pre- and post-COVID-19 periods (OR 0.52, 95% CI 0.44–0.60). TB/HIV co-infection cases declined from 28.5% (n = 766) in 2018 to 8.9% (n = 400) in 2023 (p = 0.002), while HIV-negative cases rose markedly (p = 0.027). Overall, 97.2% of children achieved favorable outcomes. Unfavorable outcomes were common among children who were HIV/TB co-infected, under five years, and 10–15 years.
Conclusion
Childhood TB case notifications increased significantly from 2018 to 2023, indicating improved detection, though with notable regional and HIV-related disparities. Treatment outcomes were generally favorable. HIV-positive children and older age groups faced higher risks of unfavorable outcomes. Targeted interventions are needed to address disparities in case detection and treatment success.
BiCervi: Pap smear microscopy image dataset for cervical cancer detection and classification
(Elsevier Inc., 2026-07-15) Mbelwa, Hope; Leo, Judith; Kahesa, Crispin; Munema, Asafu; Mkoba, Elizabeth
Cervical cancer is still a major public-health challenge, especially in low and middle-income countries where there are limited numbers of specialists to review Pap smears. While Pap smear screening is widely used, manual reading is slow and can vary from one expert to another, which makes data-driven decision support increasingly important. However, Pap smear imagery datasets from African screening settings are still limited, slowing down the development and fair evaluation of machine-learning models. This article presents a curated dataset of Pap smear microscopy images collected at The Ocean Road Cancer Institute (ORCI) in Tanzania. Images were obtained using a digital microscope with a 10 × /0.25 objective lens, and stored as RGB JPEG images at a resolution of a 2592 × 1944 pixels. The Bethesda System for reporting cervical cytology was used to label the images and organize them into eight diagnostic categories: Atypical Squamous Cells of Undetermined Significance (ASC-US), Atypical Squamous Cells, cannot exclude High-grade Squamous Intraepithelial Lesion (ASC-H), Atypical Glandular Cells (AGC), High-grade Squamous Intraepithelial Lesion (HSIL), Low-grade Squamous Intraepithelial Lesion (LSIL), Negative for Intraepithelial Lesion or Malignancy (NILM), Squamous Cell Carcinoma, and Adenocarcinoma. Labels were independently reviewed by two experts for consistency, and disagreements were resolved through adjudication to reach a final decision; images that could not be labeled with sufficient confidence were excluded during quality control. The resulting dataset comprises 3,000 images and can be used to develop Artificial Intelligence-based tools for cervical cancer detection.
Strategies for enhancing methane production from coffee pulp via co-digestion, urea supplementation, and biochar-assisted process stabilisation
(Elsevier Ltd., 2026-07-29) Oyetade, Joshua; Nason, Abigail; Mulimi, Lilian; Kolajo, Oluwafemi; Adeeyo, Adeyemi; Fayemi, Omolola; Machunda, Revocatus L
offee pulp (CP), a lignocellulosic agro-industrial residue rich in organic matter, contains phenolic compounds and other constituents that can limit anaerobic digestion (AD) performance. This study evaluated semi-continuous AD of CP in continuously stirred tank reactors under mesophilic conditions (37 °C), comparing co-digestion with coffee wastewater (CWW) and sisal wastewater (SWW) against CP mono-digestion. Co-digestion achieved stable reactor performance, with methane production rates of 564 ± 89 and 624 ± 92 mL CH4/L/day and methane contents of 56–59%. This improved performance was associated with enhanced nutrient balance (C/N = 23.8), dilution of potential inhibitory compounds, and low VFA concentrations (<1 g/L). In contrast, CP mono-digestion resulted in process instability, characterised by reduced methane production, VFA accumulation (>1.5 g/L), pH decline, and nitrogen limitation (TAN = 56.0–64.8 mg/L). Urea supplementation restored nutrient availability and reactor stability, resulting in methane production of 343 ± 18 mL CH4/L/day. Although combined urea and biochar supplementation supported recovery (326 ± 26 mL CH4/L/day), the independent effect of biochar could not be isolated, and biochar did not prevent instability at increased organic loading rates. Batch assays further showed that inoculum adaptation enhanced initial methane production kinetics, whereas cattle manure inoculum achieved the highest final methane yield (328 ± 8 mL CH4/g VS). Overall, co-digestion with agro-industrial wastewaters represents an effective strategy for improving CP digestion, while maintaining adequate nitrogen availability is critical for stable CP mono-digestion.
Sublethal Pyriproxyfen Exposure Alters Anopheles arabiensis Fitness and Pyrethroid Susceptibility Without Trans-Generational Carry-Over
(MDPI, 2026-02-26) Mnzava, Simoni; Mmbaga, Augustino; Mutashobya, Anitha; Muyaga, Letus; Mwema, Mwema; Ngowo, Halfan; Lwetoijera, Dickson
Background: Pyriproxyfen (PPF), a juvenile hormone analog, is a promising chemical for autodissemination strategies, where mosquitoes aid in transferring insecticides to their breeding sites. This study evaluated the effects of sublethal PPF doses on Anopheles arabiensis fitness (fecundity, fertility, and body size) and pyrethroids susceptibility across three generations. Methods: Laboratory-reared, pyrethroid-resistant mosquito larvae were exposed once to sublethal PPF concentrations of (0.0003, 0.0006, 0.0008, and 0.001 mg a.i./L), which caused emergence inhibition rates of 5%, 10%, 15%, and 20%, respectively, alongside a control group. Emerged adults were tested for susceptibility to 0.75% permethrin, 3.75% permethrin, and 0.05% deltamethrin using WHO tube bioassays. Knockdown was recorded at 1 h, mortality at 24 h post-exposure, while fecundity, fertility, and body size were measured across three generations. Results: First-generation Anopheles arabiensis emerging from PPF-treated larvae showed reduced susceptibility to 0.75% permethrin and 0.05% deltamethrin compared to controls. Mortality from permethrin dropped from 22.7% in the controls to 11% and then 3% at 0.0003 and 0.001 mg a.i./L. For deltamethrin, mortality fell from 62.7% to 36% and then 23.3% at the same concentrations. Knockdown at 60 min was also significantly reduced, with permethrin KDT60 dropping from 41.3% in controls to 9.3% and 3.3%, and deltamethrin KDT60 from 79.7% to 66.7% and 65%. No significant differences were observed in subsequent generations (p > 0.05). PPF exposure also induced notable fitness costs in the first generation: mean wing length decreased from 3.07 mm in controls to 2.88–2.66 mm (6–13% reduction), mean egg production dropped from 30.1 to 13.9–18.8 eggs per female (37–54% reduction), and egg hatching rate declined from 87% to 79–82% (6–9% reduction). Conclusions: These findings suggest that sublethal PPF doses can temporarily enhance insecticide resistance without leading to heritable resistance and negatively impact key mosquito fitness traits. PPF may thus be a valuable addition to integrated vector management strategies.
Feasibility of biochemical assessment of vitamin D status among pregnant women in Dodoma, Tanzania: a pilot study
(Research square, 2026-06-24) Anatoli, Antony
Vitamin D deficiency during pregnancy is associated with adverse maternal and neonatal outcomes. Despite abundant sunlight exposure in Tanzania, evidence regarding vitamin D status among pregnant women remains limited, particularly in central Tanzania. This pilot study assessed the feasibility of
biochemical assessment of vitamin D status among pregnant women attending antenatal care services in Dodoma city and generated preliminary estimates of vitamin D status.