Transactions of The Royal Society of Tropical Medicine and Hygiene
◐ Oxford University Press (OUP)
Preprints posted in the last 7 days, ranked by how well they match Transactions of The Royal Society of Tropical Medicine and Hygiene's content profile, based on 16 papers previously published here. The average preprint has a 0.02% match score for this journal, so anything above that is already an above-average fit.
Tchum, E. K. Y.; Koto, J. E.; Kanyoke, F.; Opoku, O.; Ussher, F.; Dassah, S. D.; Amoani, B.; Tchum, S. K.; Nyarko, E.
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Background Affecting 40% of infants and young children worldwide, anaemia in sub-Saharan Africa hampers cognitive and physical development, often in ways that cannot be reversed. Iron-based micronutrient powders (MNPs) are recommended to combat anaemia, but concerns remain about their safety and effectiveness in malaria-endemic areas. We evaluated the impact of iron-based MNPs on growth measurements and malaria-related anaemia among preschool children in Ghana. Methods We conducted a secondary analysis of a cluster-randomized, double-blind, placebo-controlled trial in the Bono Region, Ghana. Children aged 6-35 months (n=1,958) received daily MNP containing 12{middle dot}5mg elemental iron or placebo for five months. Anthropometric indices, haemoglobin, and malaria parasitaemia were assessed at baseline and endline. Adjusted analysis of covariance (ANCOVA) models estimated effects on height-for-age (HAZ), weight-for-age (WAZ), and weight-for-height (WHZ) z scores. Binomial regression with identity link estimated risk differences for malaria-induced anaemia. Cluster-robust standard errors were applied at the compound level, and intracluster correlation coefficients (ICCs) were estimated. Results 1,815 (92{middle dot}7%) children completed the endline survey, but 1,806 were included in the final analysis. Baseline characteristics were balanced between groups. Iron-containing MNP had no significant effect on endline HAZ ({beta}=0{middle dot}026, p=0{middle dot}609), WAZ ({beta}=-0{middle dot}015, p=0{middle dot}719), or WHZ ({beta}=-0{middle dot}035, p=0{middle dot}463). However, the intervention reduced the risk of malaria-induced anaemia (risk difference 0{middle dot}050, 95% CI 0{middle dot}004-0{middle dot}096; p=0{middle dot}032). Female sex was associated with higher HAZ ({beta}=0{middle dot}149, p=0{middle dot}005). Conclusion Iron-containing MNP did not improve short-term growth but was associated with a modest reduction in malaria-induced anaemia. These findings support the safe use of iron fortification in malaria-endemic settings while underscoring the need for integrated strategies to address persistent growth faltering and gender specificity.
Lareef, S.
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BackgroundLymphatic filariasis remains a public health concern in many endemic regions, where chronic disease persists despite substantial reductions in transmission. In Ghana, more than two decades of mass drug administration have significantly reduced disease prevalence and transmission; however, chronic manifestations and gaps in community understanding continue to be reported in parts of the north. This study assessed infection status, chronic morbidity burden, and community knowledge in a rural setting in northern Ghana approaching elimination. Methodology/Principal FindingsA community-based cross-sectional study was conducted in Birifor, northern Ghana, from October 2024 to January 2025. A total of 261 residents aged ten years and above were selected using random sampling. Data collection included structured questionnaires, clinical examination for chronic disease, and night blood microscopy for the detection of infection. No microfilariae were detected (0/261; 0%). However, chronic lymphoedema was identified in five individuals (1.9%), all aged over 40 years. Awareness of the disease was high (95.8%), yet only 39.5% of participants demonstrated good community knowledge and perceptions and self-reported preventive practices. Misconceptions regarding transmission, particularly beliefs that the disease is hereditary or caused by spiritual factors, were common. Participation in mass drug administration was high (93.1%). Despite this, chronic disease imposed a notable socioeconomic burden: all affected individuals reported loss of income, and 60% reported additional household income loss due to caregiving. Conclusions/SignificanceThese findings suggest that transmission in the study area is likely very low, although residual infection cannot be excluded; however, chronic disease and gaps in community knowledge persist. Strengthening morbidity management, improving community education, and providing support for affected households are essential. Sustained surveillance and integrated approaches will be critical to prevent resurgence and support long-term elimination efforts. Author SummaryLymphatic filariasis, also known as elephantiasis, is a mosquito-borne disease that can cause long-term swelling of the legs, arms, or genitals. Global efforts have greatly reduced its occurrence, especially through repeated mass drug administration to afflicted communities. However, many people continue to live with chronic swelling caused by past infections, which can affect their ability to work and participate fully in daily life. In this study, we examined the current situation of lymphatic filariasis in a rural community in northern Ghana that has received many years of treatment. We tested people for active infection, assessed signs of chronic disease, and explored what community members know and believe about the disease. We found no evidence of active infection, suggesting that transmission is now very low. However, some individuals were still living with chronic swelling and reported loss of income, while households also experienced financial strain due to caregiving. Although most people had heard of the disease, many did not fully understand how it is transmitted. Our findings show that reducing transmission alone is not enough. Continued education, community support, and access to care are needed to address the long-term impact of the disease and support ongoing elimination efforts.
Ogwel, B.; Awuor, A. O.; Onyando, B. O.; Ochieng, R.; Hossain, M. J.; Conteh, B.; Mujahid, W.; Shaheen, F.; Munthali, V.; Malemia, T.; Tapia, M.; Keita, A. M.; Nasrin, D.; Kosek, M. N.; Qadri, F.; Kotloff, K. L.; Pavlinac, P. B.; McQuade, E. T. R.
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Although the co-occurrence of diarrhea and malnutrition is well documented, research has largely focused on the acute management of diarrheal illness. Despite its importance, longitudinal evidence characterizing post-diarrheal recovery trajectories is sparse. We sought to characterize post-diarrheal nutritional recovery trajectories among children aged 6-35 months who were malnourished at enrollment using data from the Enterics for Global Health (EFGH) Shigella Surveillance study (2022-2024). EFGH enrolled children aged 6-35 months presenting with medically-attended diarrhea and followed them at 4 weeks and 3 months post-enrollment. This analysis included children with baseline wasting, stunting, or underweight (z-score < -2) and complete anthropometric follow-up. Latent class mixed-effects models were used to identify distinct post-diarrheal growth trajectories based on changes in anthropometric z-scores over time. Multinomial modified Poisson regression models examined associations between baseline factors and trajectory membership. Among 9,480 enrolled children, 16.5% (n=1,561) were wasted, 22.7% (n=2,155) stunted, and 21.0% (n=1,994) underweight at baseline. Wasting showed greater recovery potential (80.8%) compared with stunting (38.5%) and underweight (40.3%). Recovery was shaped by factors across multiple levels. Clinical severity markers ( prolonged diarrhea, dehydration, and hypoxemia) increased the risk of nutritional failure. Age also influenced outcomes: infants were more likely to worsen, whereas older toddlers more often experienced stagnation. Interventions including exclusive breastfeeding, oral rehydration therapy, appropriate antibiotics, and zinc supplementation, improved outcomes, while unimproved sanitation undermined recovery. These findings highlight the need for integrated strategies combining infection control, nutritional rehabilitation, and water, sanitation, and hygiene interventions tailored to the childrens developmental stage. Key MessagesO_LIPost-diarrheal nutritional recovery is highly heterogeneous, with wasting showing the greatest potential for improvement, while stunting and underweight often result in persistent growth stagnation. C_LIO_LIBaseline anthropometric deficits alone are insufficient to predict recovery, highlighting the need for dynamic monitoring and individualized management. C_LIO_LIInfants are particularly vulnerable to acute nutritional deterioration, while older toddlers frequently experience growth stagnation. C_LIO_LIModifiable protective factors including exclusive breastfeeding, ORS, zinc, and appropriate antibiotics, improved outcomes, whereas poor sanitation undermined recovery. C_LIO_LIIntegrated strategies, tailored to a childs developmental stage, combining clinical care, nutrition, and environmental interventions are critical to support sustained child growth and development. C_LI
Mahato, R. K.; Dahal, G.; Kandel, S.; Chaudhary, A.; Paudel, S. R.; Khaniya, R.; Shakya, P.; Devkota, B. P.; Sapkota, B. P.; Poudel, K. P.; Bajracharya, B.; Shrestha, D.; Jha, C. B.; Neupane, R.; Dhakal, K. B.; Bennani, K.
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Background Nepal has set a goal to eliminate lymphatic filariasis (LF) by 2030. As of 2024, Nepal has stopped the mass drug administration (MDA) in 56 of the 64 endemic districts and completed two rounds of MDA in six districts with persistent LF ([≥]2% antigen prevalence) using the three-drug regimen of Ivermectin, Diethylcarbamazine, and Albendazole (IDA), exceeding 65% coverage. We subsequently conducted an Epidemiological Monitoring Survey (EMS) to assess the impact of the MDA in reduction of LF infection prevalence below the transmission threshold and examine the factors associated with it. Methods We conducted a cross-sectional EMS nine months after MDA in 12 evaluation units (EUs) across six districts, with two sites per EU. We recruited a total of 7,343 individuals aged [≥]20 years, sampled using multi-stage sampling, ensuring at least 300 blood samples collected per site. We collected data on demographics and MDA participation. We performed the LF antigen testing for all participants, followed by night blood microfilariae testing in antigen-positive individuals. Statistical analyses included non-parametric tests, Chi-square and Fishers Exact tests, and multivariable logistic regression to assess outcomes after adjusting for potential confounders. Results Nine of 12 evaluation units (EUs) recorded <1% microfilaremia, meeting the WHO threshold for passing EMS, while three EUs failed with [≥]1% prevalence in at least one site. Antigen and MF prevalence were 4.47% and 0.34%, respectively (ratio 13:1). Both Antigen and MF prevalences were significantly associated with female sex (AOR= 0.564, 95% CI: 0.441-0.721 and AOR = 0.326, 95% CI: 0.129-0.826 respectively) and participation in the most recent MDA round (AOR = 0.477; 95% CI: 0.385-0.591 and AOR = 0.089; 95% CI: 0.017-0.464 respectively). MDA uptake was influenced by age (<40 years, AOR = 0.72; 95% CI: 0.653-0.793), sex (female, AOR = 1.438; 95% CI: 1.29-1.603), cross-border residence (AOR = 0.616; 95% CI: 0.558-0.681), and occupation (agriculture and housewife, AOR = 1.144; 95% CI: 1.008-1.298). MF prevalence was also associated with younger age (<40 years, AOR = 0.211; 95% CI: 0.071-0.626). Conclusion The survey indicates progress toward LF elimination, with nine of twelve EUs achieving WHOs <1% microfilaremia threshold after two rounds of IDA-MDA. However, transmission persists in three sites, likely linked to poor MDA participation among specific subgroups--particularly males, younger adults, and cross-border populations. Strengthening MDA coverage and compliance across all demographic and occupational groups, with special focus on border areas, is essential to achieve LF elimination in Nepal.
Koskei, G.; Karanja, S.; Ndugu, Z. W.; Anino, C. O.
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Child undernutrition remains a major public health challenge in Kenya. Suboptimal feeding practices contribute significantly to persistent underweight and stunting. This study evaluated the effect of a community-based Positive Deviance Hearth (PDH) intervention on feeding practices among children aged 6-59 months in Sub County within a County of study. The study adopted a two-group pretest-posttest randomized experimental study design conducted for six months period, among 84 caregiver-child pairs in intervention and control groups. A multi-stage sampling was employed to identify study settings and participants. Structured and pretested questionnaires, 24-hour food recall questionnaires and meal diversity questionnaires were used for data collection at pre-intervention and post-intervention periods. Data was analyzed using R software v.4.5.2. The differences between intervention and control groups at baseline and endline were assessed using difference-in-difference analysis, relevantly summarized using adjusted DID estimates, 95% confidence intervals and p-values, with p<0.05 considered significant. The PDH intervention significantly improved feeding practices among children 6-59 months. Meal frequency increased for 9-23 months (DiD = +1.4; 95% CI: 1.2-1.7; p = 0.034) and 24 months and above (DiD = +1.2; 95% CI: 1.1-1.5; p = 0.017), and dietary diversity rose (DiD = +1.3; 95% CI: 1.1-1.9; p < 0.001). Nutrient-dense food consumption improved, including legumes (DiD = +32.6%; p < 0.001) and animal-source foods (DiD = +35.4%; p < 0.001). Energy and protein intake increased across all age groups (p < 0.05), and micronutrients iron, vitamin A, vitamin C also rose significantly (p < 0.05). The PDH intervention substantially improved caregiver feeding practices, increased dietary diversity, and enhanced macro- and micronutrient intake, demonstrating its effectiveness as a scalable, community-driven strategy for sustainably improving child nutrition in high-burden settings.
Ochieng', E. A.; Muita, J. W.; Olewe, T.
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ABSTRACT Background: Malaria remains a leading public health burden in sub-Saharan Africa, disproportionately affecting children under five years. In response, Kenya introduced the RTS,S/AS01 malaria vaccine in selected regions, including Siaya County where malaria transmission is endemic. Despite this milestone, uptake has been inconsistent, with hesitancy emerging as a significant barrier. Objective: This study aimed to determine factors associated with malaria vaccine hesitancy among caregivers of children 6-59 months in Ugenya Subcounty, Siaya County. Methodology: A cross-sectional mixed methods design was employed involving 425 caregivers and 15 healthcare workers and County health officials between January to February 2025. Quantitative data were collected using structured questionnaires and analyzed in Stata version 17 through descriptive statistics, bivariate analysis at 20% significance threshold, and multivariable logistic regression at 5% level to determine key factors associated with malaria vaccine hesitancy. Qualitative data from 15 key informant interviews were transcribed verbatim and thematically analyzed using NVivo. Thematic analysis, guided by a predefined codebook, was used to identify recurring patterns and extract key themes, which were illustrated with direct quotations from participants Results: Overall, 42.9% of caregivers (n=181; 95% CI: 38.9%-47.3%) reported hesitancy. Significant predictors included caregiver age, marital status, family size, access to health facilities, and vaccine availability. Single caregivers, those from smaller households, and those facing health facility access challenges were more likely to be hesitant to malaria vaccine. Despite high levels of knowledge, misconceptions and misinformation about vaccine safety, often spread via social media persisted. Conversely, caregivers relying on healthcare workers and mainstream media showed greater acceptance of malaria vaccine. Conclusion and Recommendations: Malaria vaccine hesitancy remains significant at 42.9%, driven by demographic factors such as younger age, single status, and smaller household size. Structural barriers including limited vaccine availability and poor access to health facilities further contribute to reluctance. Although knowledge and awareness were high, misinformation, particularly from social media, persisted, while information from healthcare workers improved acceptance. Addressing these gaps through targeted community engagement, improved access, and trusted communication channels is essential to increase uptake of malaria vaccine.
Johnson, L. F.; Kubjane, M.; Imai-Eaton, J. W.; Brown, L.; Jamieson, l.; Naidoo, P.; Tanna, G.; Meyer-Rath, G.
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Background: The WHO End TB strategy targets 80% and 90% reductions in TB incidence and mortality, respectively, between 2015 and 2030. Objective: We assess which epidemiologic factors, including existing and new interventions, are most critical to reducing future TB in South Africa. Methods: We adapted an existing mathematical model of TB and HIV in South Africa. Prior distributions were specified to represent uncertainty ranges for 27 model parameters that are highly uncertain and potentially important in driving future TB dynamics. Latin Hypercube Sampling was used to sample 1000 parameter combinations from these distributions, and the model was projected to 2040 for each. Partial rank correlation coefficients (PRCCs) were calculated to assess correlation between each parameter and average adult TB incidence and mortality rates over 2025-2040. Results: Adult TB incidence and mortality rates in South Africa are projected to decline by 46% (95% CI: 17-69%) and 54% (95% CI: 21-84%) respectively by 2030, relative to 2015. The parameters most strongly associated with future TB incidence are the increase in microbiological testing in symptomatic individuals due to near-point-of-care/tongue swab (NPOC/TS) testing (PRCC=-0.67), reductions in social contact rates post-COVID (PRCC=-0.61), the probability of sputum testing in symptomatic individuals in the absence of NPOC/TS testing (PRCC=-0.39), and the efficacy of TB preventive therapy (PRCC=-0.35). TB mortality predictors are similar. Conclusions: Increasing testing among people with TB symptoms, including through new NPOC/TS technologies, is likely to have the largest impact on progress towards End TB goals in South Africa, though attainment by 2030 is unlikely.
Hossain, H.; Mohiuddin, A. S. M.; Islam, S.; Insan, M.; Ahmed, S.; Brishty, K. A.; Parvej, M.; Yadav, S. K.; Ahmed, S.; Das, S. R.; Rahman, M. M.; Rahman, M. M.; Paul, B.
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BackgroundAnimal bites represent a significant public health concern due to the risk of injuries and transmission of zoonotic diseases such as Rabies, particularly in low and lower- middle-income countries (LMICs). Understanding the epidemiological characteristics of animal bite incidents is essential for improving the prevention and control strategies. This study aimed to characterize the epidemiological patterns and characteristics of animal bite cases in Sylhet, Bangladesh. Methodology/Principal findingsWe conducted a retrospective analysis of 6,565 animal bite cases reported between January 1 and December 31, 2024, in Sylhet, Bangladesh. Data on demographic characteristics, type of biting animal, site of bite, and exposure category were collected and analyzed to determine associations using correlation analyses and chi-square tests. Among the victims, 3,917 (60%) were male and 2,648 (40%) were female and young adults aged 20-39 years comprised the largest group (39% of cases). The majority of cases (88.1%) originated from urban areas within Sylhet City Corporation. Cats were the leading cause of bites (56.6%), followed by dogs (35.0%) and monkeys (7.5%), suggesting a shift from the traditional dog-dominated pattern. The most frequently affected anatomical sites were the legs (50.3%) and hands (40.9%). Most exposures were classified as World Health Organization (WHO) Category II (98.2%). Bite incidents showed moderate seasonal variation, with peaks in spring and early autumn. A significant declining temporal trend was observed for monkey bites (R = -0.59, p = 0.044), whereas cat and dog bite patterns remained relatively stable throughout the year. Significant associations were identified between bite site and age group, as well as between biting animal and demographic characteristics (p < 0.05). Conclusion/SignificanceThese findings highlight the epidemiological patterns of animal bites in Sylhet and emphasize the need for strengthened public awareness, surveillance, and preventive strategies to reduce animal bite incidents and associated zoonotic disease risks. SynnopsisO_LIA large-scale retrospective analysis of 6,565 animal bite cases revealed a cat-dominant bite pattern (56.6%), contrasting with the traditional dog-dominant paradigm in South Asia. C_LIO_LIYoung adults (20-39 years) and males (60%) were disproportionately affected, reflecting occupational and behavioral exposure risks. C_LIO_LIUrban residents (88.1%) accounted for the majority of cases, highlighting the growing public health burden of animal bites in rapidly urbanizing settings. C_LIO_LIThe most frequently affected anatomical sites were the legs (50.3%) and hands (40.9%). Bite incidents showed moderate seasonal variation, with peaks in spring and early autumn. C_LIO_LICategory II exposures (98.2%) predominated, indicating a high burden of seemingly minor injuries that may be underestimated in rabies prevention strategies. C_LI
Oliveira Roster, K. I.; Rönn, M. M.; Gorenburg, E. R.; Partl, D. K.; Anderegg, N.; Abel zur Wiesch, P.; Au, C.; Kouyos, R. D.; Martinez, F. P.; Low, N.; Grad, Y. H.
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Numerous factors may influence the optimal rollout of new gonococcal antibiotics. We compared eight rollout strategies using a gonorrhea transmission model and ranked strategies by the number of gonococcal infections and clinically useful antibiotic lifespan. Rankings were most sensitive to the starting ceftriaxone resistance prevalence and screening frequency.
Gil-Salcedo, A.; Gazzano, V.; Arsene, S.; Durand, A.; Roger, S.; Prots, L.; Laurencin, N.; Chanard, E.; Duez, A.; Le Naour, E.; Bausset, O.; Ghali, B.; Strzelecki, A.-C.; Felloni, C.; Levillain, R.; Fargeat, C.; Lefrancois, S.; Feuerstein, D.; Visseaux, B.; Escudie, L.; Visseaux, C.; Leclerc, C.; Haim-Boukobza, S.
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Background: Since September 2024, France has implemented a national reform allowing prescription-free access (PFA) to sexually transmitted infection (STI) screening in medical biological laboratories (MBLs). This study aims to characterize the populations undergoing STI testing according to their access modality and evaluate the probability of test positivity in relation to testing pathway, sex, and age groups. Methods: We conducted a cross-sectional analysis of all individuals screened for Chlamydia trachomatis, Gonorrhoea, human immunodeficiency virus (HIV), hepatitis B virus (HBV), and syphilis by treponemal-specific immunoassay (TSI) in Cerballiance MBLs between Mars 2025 and February 2026. Multivariable logistic regression models stratified by sex and adjusted for age and region assessed associations between screening modality and STI positivity. Results: Among 1,008,737 individuals included, 27.8% were under PFA and 72.2 under prescription-based access (PBA). PFA users were more frequently male (47.4% vs. 36.3%, p<0.001) and aged 20-39 years (34.0%, p<0.001). Overall positivity rates differed by modality: PFA was associated with higher detection of Chlamydia (4.6% vs. 3.6%). PBA group showed more positive cases of syphilis (3.4% vs. 1.2%), HBV (1.3% vs. 0.4%), and HIV infections (0.3% vs. 0.2%, all p<0.001). Co-infection and gonorrhoea proportions did not significantly differ between modalities. Conclusions: PFA substantially increased STI screening uptake, particularly among young adults and men, and enhanced detection of bacterial STIs. PBA remains essential for diagnosing viral and chronic infections. These findings highlight the complementary roles of both access strategies and support PFA screening as an effective public health intervention to broaden STI detection and reduce transmission.
Wandji Djouonang, B.; Olungah, C. O.; Atsali, E.; Kihara, A.-B.; Omanwa, K.; Obimbo, M. M.; Ogengo, J.
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Objective To analyse sociodemographic determinants of maternal health indicators in Kenyas conflict-affected regions. Methods A cross-sectional secondary analysis of the 2022 Kenya Demographic and Health Survey (KDHS) was conducted. Conflict-affected counties were identified using ACLED (>25 fatalities). The sample included 1,060 women aged 15-49 years. Outcomes were adequate antenatal care (ANC 4+), facility delivery, and skilled birth attendance (SBA). Predictors included age, education, wealth, employment, residence, and county; intimate partner violence was adjusted for. Weighted descriptive statistics, chi-square tests, and multivariable logistic regression were applied (p<0.05). Results Six counties met conflict criteria. While 90.2% of women attended at least one ANC visit, only 53.5% achieved ANC 4+. Facility delivery and SBA were 68.2% and 72.2%, respectively. Adolescents (15-19) were least likely to attain adequate ANC; women aged 20-24 had higher odds (aOR=1.83; 95% CI: 1.01-3.34). Education strongly predicted outcomes: higher education increased ANC 4+ (aOR=2.74; 95% CI: 1.19-6.34) and facility delivery (aOR=2.72; 95% CI: 1.15-6.47). Wealth showed strong gradients: middle quintile increased facility delivery (aOR=5.50; 95% CI: 2.14-14.14), while richer quintile increased SBA (aOR=11.04; 95% CI: 2.06-59.25). Rural residence reduced facility delivery (aOR=0.32) and SBA (aOR=0.22). County disparities persisted. IPV was not independently associated. Conclusion Maternal health indicators in conflict-affected Kenya follow a marked inequity gradient. Adolescents, rural residents, and socioeconomically disadvantaged women are most excluded. Strengthening adolescent ANC continuity, reducing rural access barriers, and investing in education and economic empowerment are critical for improving outcomes.
ONOVO, A. A.; Omoro, G.; Maswai, J.; Owuoth, J.; Kirui, D.; Odero, L.; Makone, B.; Miruka, F.; Obat, E.; Yegon, P.
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Background Although Kenya's HIV programme has long prioritized high-burden counties for intensified paediatric interventions, a critical evidence gap remains in developing integrated analytic frameworks that can objectively predict and validate paediatric HIV burden using data-driven models. We therefore developed and tested a framework that combines machine-learning (ML) prediction with geostatistical hotspot analysis, where a hotspot denotes a statistically significant spatial cluster of elevated paediatric HIV cases to strengthen data-driven surveillance and resource targeting. Methods National HIV testing data for children aged 0-14 years were analysed together with indicators from the 2022 Kenya Demographic and Health Survey. Multiple supervised ML algorithms were trained to predict the number of children living with HIV (CLHIV) across Kenya's 47 counties. Model performance was evaluated using root-mean-square and mean-absolute error. The tuned Lasso-regression model demonstrated the best predictive accuracy and generated county-level estimates for October 2022 to June 2023. These predictions were subsequently assessed for spatial autocorrelation (Moran's I) and validated using Getis-Ord Gi* statistics. Findings The model predicted 3160 newly identified CLHIV during the study period, compared with 3092 cases reported nationally. To account for differences in county population size, paediatric HIV incidence was calculated as cases per 10,000 children aged 0-14 years using 2023 census projections as the denominator. Incidence-based choropleth maps revealed that the highest reported burden was concentrated in Isiolo (11.2 per 10,000) and western Kenya (Homa Bay 7.7, Kisumu 3.6, Siaya 3.5), while model predictions identified additional high-incidence counties in eastern and northern regions. Significant spatial clustering was confirmed for both reported (z = 3.23, Moran's I = 0.22, p = 0.001) and predicted (z = 4.92, Moran's I = 0.37, p < 0.001) distributions. Thirteen counties, predominantly in western Kenya, were identified as statistically significant hotspots. Interpretation This study presents a validated methodological framework integrating ML prediction with geostatistical analysis for paediatric HIV surveillance. By expressing model outputs as population-adjusted incidence, the framework enables equitable comparison of paediatric HIV burden across counties of differing size, strengthening the evidence base for geographic prioritization and resource allocation. Funding This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Hussain, A.; Hussain, S.; Bravo de Guenni, L.; Smith, R. L.
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Ticks impose major health and economic losses on the livestock sector of Pakistan, yet uncertainty-aware maps of tick burden remain scarce. We focused on the two most common disease transmitting tick species, Rhipicephalus microplus and Hyalomma anatolicum, to produce exposure-adjusted district-level abundance estimates and predictions for unsampled areas in Punjab and Khyber Pakhtunkhwa (KPK). We compiled heterogeneous tick count records and standardized them per 100,000 animals. District-level climate and physiographic covariates were summarized via principal components analysis. Bayesian spatial models were fit in R-INLA using Gaussian likelihoods and BYM2 over a hybrid adjacency matrix. Competing non-spatial and spatial models were compared, and the best model was used to generate posterior predictions and 95% credible intervals for unsampled districts. Spatial models outperformed non-spatial alternatives and calibrated well. Model robustness was confirmed through eight independent 80/20 train-test splits, showing strong generalization with consistent predictions across seeds. For unsampled areas, R. microplus exhibited a pronounced north-south gradient with high predicted means but wide intervals in the northern highlands, indicating information gaps. H. anatolicum predictions were highest and most precise in southern Punjab. Sensitivity analysis highlighted a dominant spatial component, with modest contributions from PC1 and PC2. The Bayesian spatial models using the Besag-York-Mollie framework delivered comparable, exposure-adjusted tick abundance maps while quantifying uncertainty to guide surveillance. Results suggest a need for immediate control in confirmed hotspots and recommend targeted field sampling in high-uncertainty districts. The workflow generalizes to other vectors, pathogens, and regions for evidence-based livestock health planning.
Gupta, U. P.; Pokharel, A.; Jadhav, K.; Jadhav, I.; BC, R. K.; Subedi, S.; Gupta, M.
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Hemoglobinopathies are inherited disorders of hemoglobin, most notably sickle cell anemia and thalassemia. These conditions result from mutations in the globin genes, leading either to structural abnormalities in the globin chains or to reduced synthesis of normal globin chains. Hemoglobinopathies is a worldwide health problem according to the World Health Organization; it affects mostly the indigenous Tharu groups in Nepal. Both the global and local rates of illness and death associated with these diseases are on the rise. The objective of this study was to assess the presence of hemoglobinopathies and common mutations of the beta-globin gene within the Tharu population in western Nepal. A cross-sectional study of 1,400 Tharu individuals was conducted among individuals obtained through hospitals within the Banke district, Bardiya district, and Kailali district in western Nepal. A thorough hematological analysis was done with the use of a Sysmex XN-350 analyzer. Hemoglobin variants were detected via high-performance liquid chromatography (HPLC). The molecular characterization of the seven most common mutations of {beta}-thalassemia was performed on a subset of 20 confirmed cases by using a real-time PCR kit.The total number of cases diagnosed with hemoglobinopathies was 14.43% (n=202 out of 1,400). Sickle cell trait (HbAS) was reported as the most prevalent type of Hemoglobinopathies (8.50% of population), followed by {beta}-thalassemia trait (4.00%). In addition to these disorders were sickle cell disease (HbSS), HbE trait, and compound heterozygous states. Hematological parameters differed significantly across types of hemoglobinopathies, and the patterns of microcytic, hypochromic, and hemolytic anemia were also distinct. Commonly documented symptoms included fatigue and joint pain (42.5% and 23.1%, respectively). Molecular characterization of {beta}-thalassemia cases demonstrated that most individuals were compound heterozygotes with IVS1-6 (T>C) as the most prevalent variant. The research identified that the Tharu population in western Nepal has a significant burden of hemoglobinopathies (especially sickle cell trait and {beta}-thalassemia), highlighting the requirement for appropriate screening programs, genetic counseling and public health strategies to help manage and prevent these conditions within this particular region.
Olson, A. M.; Wood, R. C.; Sithole, N.; Govender, I.; Grant, A. D.; Smit, T.; David, A.; Stevens, W.; Scott, L.; Drain, P. K.; Cangelosi, G. A.; Shapiro, A. E.
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Background. Targeted Universal Tuberculosis Testing (TUTT) may increase tuberculosis (TB) case detection by including people who are not actively seeking TB care but are at high risk of the disease. Non-invasive tongue swab (TS) testing may facilitate TUTT. We evaluated two TS testing protocols in people with HIV (PWH) tested irrespective of TB symptoms. Methods. Study staff collected Copan FLOQSwab and Medline foam swab specimens, alongside urine and sputa, from PWH, most of whom were presenting for antiretroviral therapy initiation at primary healthcare clinics in KwaZulu-Natal, South Africa. FLOQSwabs were tested by sequence-specific magnetic capture (SSMaC) with qPCR (FLOQSwab-SSMaC). Foam swabs were tested by centrifuge-sedimentation and high-volume qPCR (foam-sedimentation). Urine lipoarabinomannan was detected using LF-LAM. The extended microbiological reference standard (eMRS) comprised any positive result on Xpert Ultra and/or liquid culture of sputum. Results. We enrolled 251 participants (median age 34 years, 56% female, 67% with self-reported TB symptoms). Participants had a median CD4 count of 347 cells/ul, and 16% (40/251) had prior TB. FLOQSwab-SSMaC was 43% sensitive (13/30) and 100% specific (131/131) relative to eMRS. Foam-sedimentation was 47% (9/29) sensitive and 100% (176/176) specific. Sensitivity increased to 52% (FLOQSwab-SSMaC) and 50% (foam-sedimentation) when sputum Xpert Ultra Trace positive results were excluded from eMRS. TS was more sensitive than urine LAM, and both sample types were more sensitive when CD4 counts were below 200. Discussion. TS testing detected about half of PWH with TB and outperformed urine LAM within this population, including among PWH with low CD4 counts.
Nguyen, A. T.; Nankabirwa, J. I.; Kakuru, A.; Roh, M. E.; Aguti, M.; Adrama, H.; Kizza, J.; Olwoch, P.; Kamya, M. R.; Dorsey, G.; Jagannathan, P.; Benjamin-Chung, J.
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Introduction: Intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine (SP) has become less effective at preventing malaria due to rising parasite resistance. IPTp with dihydroartemisinin-piperaquine (DP) alone or in combination with SP (DP+SP) dramatically lowers the risk of malaria in pregnancy compared to SP but is associated with lower birthweight and early life wasting. We estimated the effect of IPTp-DP, DP+SP, and SP on infant growth outcomes and assessed possible treatment mechanisms through a causal mediation analysis. Methods: We used infant follow-up data (N=761) from a trial (NCT04336189) that randomized pregnant women to receive monthly IPTp-DP, SP, or DP+SP. We compared weight-for-length (WLZ) and length-for-age (LAZ) z-scores between treatment arms. We assessed possible mediation through pregnancy, birth, and infancy factors using interventional indirect effect models. Results: Compared to IPTp-SP, IPTp-DP+SP decreased mean WLZ by 0.18 [95% confidence interval (CI) -0.03, 0.39] between 1-3 months and 0.28 (95% CI 0.07, 0.49) between 4-6 months, with the largest differences among primigravidae. Lower risk of active placental malaria in IPTp-DP+SP helped reduce differences in mean WLZ vs IPTp-SP (+0.06, 95% CI 0.02, 0.10). The IPTp-DP+SP arm had up to 0.28 lower mean LAZ between 7-13 months compared to IPTp-DP, particularly among children who were wasted between 0-6 months; low birthweight had a persistent, mediating effect on linear growth. Conclusion: Adverse birth outcomes contributed to early growth faltering among children born to mothers receiving IPTp-DP+SP vs IPTp-SP, but the prevention of placental malaria partially counteracted the negative effects of IPTp-DP+SP on ponderal growth.
Nickel Valerio, E. C.; Coli Seidel, G. M.; Da Silva Nunes, R.; Alvarenga Americano do Brasil, P. E.
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There is an ongoing Oropouche Fever (OF) outbreak in Brazil since 2024. There are dengue and chikungunya prediction models available, but none to help discriminate dengue, chikungunya, and OF. Objective: This study aims to develop and validate clinical prediction models for dengue, chikungunya, OF. Methods: This study uses surveillance data from Espirito Santo state / Brazil, from 2023-2025. Epidemiological investigations and biological samples were used to conclude cases as either (a) clinical-epidemiologically confirmed, (b) laboratory confirmed, or (c) discarded. The predictors were all data related to signs, symptoms, and comorbidities available in the notification forms. The analysis was performed using random forest regression models, one for each outcome, in development and validation datasets. Results: A total of 465,280 observations were analyzed, 261,691 dengue cases (56.6%), 18,676 chikungunya cases (4.0%), 12,174 OF cases (2.6%), and 179,115 discarded cases (38.6%). All three models had good discrimination and moderate to good calibration after scaling prediction. The models retained from 26 to 16 predictors each. Leukopenia and vomiting were the most discriminatory predictors for dengue, arthritis, arthralgia, and rash were the most discriminatory for chikungunya, and epidemiological features were the most relevant for OF. The dengue, chikungunya, and OF models had ROC AUC of 0.726, 0.851, and 0.896 in the validation set, respectively. Conclusion: This research identified predictors most discriminative between dengue, chikungunya, and OF. We developed and validated predictive models, one for each condition, with moderate to very good performance available at https://pedrobrasil.shinyapps.io/INDWELL/. One may use them in diagnostic work-up and arbovirus surveillance.
Deng, M. D. A.; Alayande, B. T.; Sheferaw, E. D.; Ngutete Mukundwa, P.; Fofanah, T.; Peter, M. B.; Kuron, D.; Bekele, A.; Dau, A. D.
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BackgroundAccess to safe, equitable, and affordable surgical and anesthesia care is critical to reducing the burden of surgical diseases in Africa. To understand the state of access in South Sudan, we conducted a baseline assessment of surgical services in Central Equatoria State (CES) in May 2024. ObjectivesThis study aimed to survey public healthcare facilities in CES capable of providing essential surgical services. We used the capacity to perform cesarean section, laparotomy, and open fracture management--Bellwether procedures--as a proxy for assessing workforce, infrastructure, financing, information management, and service delivery. MethodsWe used a validated and contextualized Surgical Assessment Tool developed by the Harvard Program on Global Surgery and Social Change and the World Health Organization. Data were collected at the facility level and summarized descriptively using percentages, means (standard deviations), medians (minimum, maximum), and visualized in graphs, charts, and tables. ResultsAll three public health facilities assessed could perform Bellwether procedures for their catchment populations. However, workforce availability, financing, and surgical infrastructure were major constraints. The surgical workforce density was 2.27 surgical, anesthesia, and obstetric specialists per 100,000 population. Specialized procedures--such as repair of cleft lip and palate, clubfoot, and hydrocephalus shunt--were unavailable at all sites. None had magnetic resonance imaging (MRI) machines. The total average annual facility budget was $918,850, ranging from $3,960 to $800,000 at the teaching hospital--insufficient for proper operations. ConclusionWhile Bellwether procedures are routinely performed, access to quality and affordable care is compromised by deficits in workforce, financing, and infrastructure. We recommend that the Ministry of Health scale this survey nationally and develop a surgical policy and strategic plan focused on improving infrastructure, workforce, and financing for surgical and anesthesia care in South Sudan.
Abubakar, A.; Inuwa, S. M.; Ali, M. J.; Abdullahi, K. M.; Doe, A.; Ngaybe, M. G. B.; Madhivanan, P.; Musa, J.
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Women living with HIV face about a six-fold higher risk of cervical cancer, yet screening uptake remains low in many sub-Saharan African settings. We explored factors influencing repeated decisions to decline cervical cancer screening during routine HIV care among women living with HIV at a large HIV clinic in Jos, Nigeria. Between September and December 2024, we conducted an exploratory qualitative study at the AIDS Prevention Initiative in Nigeria Clinic in Jos, Nigeria. We purposively recruited 27 women living with HIV aged 21 to 65 years who had never undergone cervical cancer screening and had repeatedly declined screening offers during routine HIV care, including at the current clinic visit. Semi-structured in-depth interviews were conducted in English or Hausa, audio-recorded, transcribed verbatim, and translated into English where needed. Data were analyzed thematically using theory-informed coding based on the Health Belief Model and Social Ecological Model. Among 27 women living with HIV who had repeatedly declined screening, perceived susceptibility was often low or uncertain despite recognition of cervical cancer severity. Perceived benefits were acknowledged but were frequently outweighed by overlapping barriers, including knowledge gaps and misinformation, indirect and downstream costs, emotional barriers, logistical constraints, clinic-flow and service-delivery barriers, and anticipated stigma. Education, reminders, and supportive clinic processes acted as cues to action, and most participants expressed willingness to screen in future. Among women living with HIV at this clinic who repeatedly declined screening when it was offered, perceived benefits were often outweighed by multilevel barriers. Screening programs may integrate fear-reduction and stigma-sensitive counseling with practical service delivery improvements, including shorter waiting times, reduced indirect costs, predictable and streamlined clinic flow, and consistent provider invitations and reminders, while addressing misinformation through community-embedded, culturally tailored messaging. These strategies may improve screening uptake and support more equitable cervical cancer prevention for women living with HIV in similar HIV-care settings.
Abidha, C. A.; Amevor, B. S.; Mank, I.; Oguso, J.; Mbata, M.; Coulibaly, B.; Denkinger, C. M.; Sorgho, R.; Sie, A.; Muok, E. M. O.; Danquah, I.
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Background: Sub-Saharan Africa (SSA) still experiences a high burden of micronutrient deficiencies. For monitoring of micronutrient status among young children in SSA, non-invasive alternatives to blood-based biomarkers are desirable. Handheld Raman spectrophotometry appears to offer this alternative to quantify intracellular stores of micronutrients. In rural Burkina Faso and Kenya, we validated the Cell-/SO-Check device (ZellCheck(R)) against conventional laboratory-based methods. Methods: For this validation study, we recruited children aged [≥]24 months attending routine clinics within the Health and Demographic Surveillance Systems (HDSS) in Siaya and Nouna. Anthropometric measurements and venous blood samples were taken. Plasma ferritin, soluble transferrin receptor (sTfR) and C-reactive protein (CRP) were measured by ELISA, and plasma zinc by atom absorption. The spectrometer was used to quantify zinc and iron. For continuous outcomes, we generated Bland Altman plots and calculated bias and limits of agreement (LoA). For binary outcomes, we produced Receiver Operator Characteristic (ROC) areas under the curve (AUC), and estimated sensitivity, specificity and predictive values. Results: We analysed data of 48 children from Burkina Faso and 54 children from Kenya (male: 53%; age range: 24-66 months). According to spectrophotometry, the proportions of iron deficiency and zinc deficiency were 16.7% and 25.5%, respectively. The median concentrations were for ferritin 24.0 {micro}g/L (range: 2.0-330.0), for sTfR 5.7 mg/L (2.8-51.0), and for zinc 9.9 {micro}mol/L (5.2-25.0). The corresponding bias for iron levels by spectrophotometry was 42.4 with LoA: -18.7, 103.6. The bias for zinc levels was 7.5 with LoA: -49.3, 64.2. For the classification of deficiency, the ROC-AUC, sensitivity, and specificity for spectrophotometry vs. biomarker-based diagnosis were for iron deficiency 0.62, 68% and 55%, respectively, and for zinc deficiency 0.55, 33% and 91%, respectively. Conclusions: The Cell-/SO-Check device may be used to rank children in population-based studies in SSA according to their zinc status, but not iron status. The method should not replace the standard laboratory measurements for clinical diagnoses of zinc and iron deficiencies.