The American Journal of Tropical Medicine and Hygiene
● American Society of Tropical Medicine and Hygiene
Preprints posted in the last 7 days, ranked by how well they match The American Journal of Tropical Medicine and Hygiene's content profile, based on 60 papers previously published here. The average preprint has a 0.17% match score for this journal, so anything above that is already an above-average fit.
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
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.
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.
ISMAIL, A. J.; MOETI, L.; DARKO, D. M.; WALKER, S.; SALEK, S.
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Background Regulatory inconsistency across African countries contributes to duplicative scientific assessments, prolonged approval timelines, and delayed access to essential medical products. To inform the operationalisation of the African Medicines Agency (AMA), the African Medicines Regulatory Harmonisation (AMRH) programme implemented Africa's first continental pilot study for the scientific evaluation and listing of human medicinal products. This study evaluates the pilot's procedural performance and examines how continental scientific opinions were translated into national regulatory decisions through reliance mechanisms. Methods and Findings A mixed-methods programme evaluation was conducted using regulatory datasets generated during the pilot study. Quantitative data included assessment timelines, GMP inspection outcomes and national post-listing regulatory actions. Retrospective qualitative thematic analysis was applied to governance documents and National Regulatory Authority (NRA) feedback to identify legal, institutional and procedural determinants influencing uptake. Of 64 expressions of interest, 24 products progressed to full evaluation and 12 received positive continental scientific opinions. Ten met the predefined performance target of [≤]210 working days. Twenty-four GMP inspections identified no critical deficiencies and aligned with global regulatory benchmarks. National uptake demonstrated active reliance: full reliance (continental opinion as primary basis for national approval) for 7 products (58%); sequential reliance (continental assessment supplemented with targeted national queries) for 3 products (25%); and supplemented national review (separate national assessment undertaken) for 2 products (17%). Products with broader market strategies achieved registration in up to 23 African countries within a median of 77 working days post-listing. Variability in uptake reflected national legal authority, administrative requirements, and applicant submission strategies Conclusions The pilot study demonstrates the feasibility of a continent-wide regulatory assessment mechanism capable of producing trusted scientific outputs and enabling reliance-based national decision-making in Africa. While reliance was widely applied, heterogeneity in national procedures and administrative sequencing affected time to national registration. Findings provide empirical evidence to inform the AMA scale-up, highlighting the need for harmonised reliance pathways, streamlined administrative processes, and coordinated digital regulatory infrastructure.
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.
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.
Priyanka, S. S.; Sujon, M. S. H.; Farzana, A.; Dasgupta, D. P.; Bhuyan, G. S.; Ali, N. B.
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Dropout from essential maternal health services across pregnancy, childbirth, and the postnatal period remains a major barrier to improving maternal and neonatal outcomes in Bangladesh. This study examined stage-specific dropout patterns along the maternal continuum of care and identified factors associated with discontinuation. We analysed nationally representative data from the Bangladesh Demographic and Health Survey 2022 for 5,162 women with a recent live birth. Dropout from antenatal care, skilled birth attendance, and postnatal care was examined using multivariable logistic regression to estimate adjusted odds ratios and 95% confidence intervals, with comparisons to BDHS 2017-18 and assessment of regional variation. Only 44% of women received four or more antenatal care visits. Of these, 33% delivered with a skilled birth attendant, and among those receiving both antenatal care and skilled delivery, only 15% received postnatal care within 48 hours. Overall, 57% dropped out before completing adequate antenatal care, with additional dropouts between antenatal care and delivery (10%) and between delivery and postnatal care (18%). Compared with 2017-18, overall dropout from the maternal continuum of care more than doubled in 2022 (5.0% to 11.7%), driven by increased antenatal care dropout, while skilled birth attendance dropout declined and postnatal care dropout increased slightly. Higher maternal education, household wealth, media exposure, and womens decision-making power were consistently associated with lower odds of dropout, whereas higher birth order increased dropout risk. Substantial regional variation was observed, with the highest overall dropout in Sylhet and the lowest in Khulna. High dropout from the maternal continuum of care in Bangladesh occurs predominantly at the antenatal care stage and is shaped by socioeconomic status, birth order, womens access to information, and regional disparities. Strengthening early antenatal engagement and womens decision-making autonomy is critical to improving continuity of maternal care and reducing preventable maternal and neonatal risks.
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.
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.
Koulidiati, J.-L.; Zoma, R. L.; Nebie, E. I.; Soumaila, Y.; Neya, C. O.; Kiendrebeogo, J. A.; Debellut, F.
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Background: In Burkina Faso, typhoid fever remains a major public health concern, with a high incidence among children younger than 15 years of age. To address this burden, the country introduced typhoid conjugate vaccine in January 2025 through a national vaccination campaign reaching children aged 9 months to 14 years. This study aimed to estimate the cost of typhoid conjugate vaccine delivery during the national campaign and to identify the main cost drivers across different administrative levels. Methods: We conducted a cross-sectional, retrospective costing study using a microcosting approach from the government perspective. We collected data from fifty health facilities, eight health districts, five health regions, and the national level. Financial and economic costs were estimated for each level, excluding vaccine and syringe costs. All costs were converted to 2024 USD using the official exchange rate. Findings: Vaccinators administered a total of 10.5 million typhoid conjugate vaccine doses. The average financial cost per dose was $0.47 (95% CI: $0.39-$0.51), and the economic cost was $2.16 (95% CI: $1.71-$2.56). Human resources and per diem payments were the main contributors to costs. Costs varied by geography, delivery strategy, and security context, with higher costs observed in rural and conflict-affected areas. The mobile-temporary posts strategy had the highest economic cost per dose ($2.02; 95% CI: $1.64-$2.40), while the fixed strategy had the highest financial cost per dose ($0.41; 95% CI: ($0.32-$0.49). Conclusion: The financial cost per dose remained within Gavi, the Vaccine Alliance's operational support range. The observed cost variations highlight the need for targeted funding and enhanced logistical support to ensure equitable access, particularly in rural and insecure areas. This study provides evidence to inform future vaccination campaigns and supports decision-making for typhoid conjugate vaccine introduction in other countries in the 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.
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.
Coelho, J. A. P. d. M.; Nascimento da Paixao, A.; Guimaraes Almeida, B.; Näslund-Hadley, E.
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Background Childhood sensory and intellectual disabilities represent significant yet under-recognized barriers to learning and human capital development. This study analyzes prevalence and severity of these conditions among 149.3 million children aged 5-19 years across 25 countries in Latin America and the Caribbean (LAC) using Global Burden of Disease 2023 data. Methods We extracted GBD 2023 estimates for vision loss, hearing loss, and intellectual disability across 25 LAC countries, stratified by age, sex, and severity. Regional estimates were calculated using population-weighted averages. Severity distributions were compared with OECD countries to contextualize regional patterns. Results: These conditions are estimated to affected 9,282,921 children (6.22%; 95% UI: 5.89-6.54%). Hearing loss was predominant, affecting an estimated 5.42 million (3.63%, 3.41-3.86), with 87.6% mild-to-moderate. Intellectual disability estimated to affected 2.56 million (1.71%, 1.58-1.85), with 61.7% borderline-to-mild. Vision loss estimated to affected 1.30 million (0.87%, 0.79-0.96), with 89% that can be effectively addressed with spectacles. Prevalence increased with age across all conditions. Male predominance was consistent for intellectual disability (2.00% vs 1.42%). Annual economic cost totaled US$19.3-29.0 billion, while comprehensive interventions would require US$9.45-14.23 billion with benefit-cost ratios of 2:1 to 15:1. Conclusions The distribution of children across milder levels of difficulty underscores the opportunity for education and public health systems to provide timely and accessible support. With approximately 88% of sensory impairments addressable through established technologies, investments in inclusive services can yield strong social and economic returns.
Conteh, B.; Galagan, S. R.; Badji, H.; Secka, O.; Bar, B. T.; Rao, S. I.; Atlas, H.; Omore, R.; Ochieng, J. B.; Tapia, M.; Cornick, J.; Cunliffe, N.; Zegarra Paredes, L. F.; Colston, J.; Islam, M. T.; Mosharraf, M. P.; Qamar, F. N.; Fatima, I.; Pavlinac, P. B.; Hossain, M. J.
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Globally, respiratory tract infections (RTI) are the main cause of morbidity, and in Low-middle-income countries (LMICs) RTI including pneumonia are a leading cause of morbidity and mortality in children <5 years. Diarrheal illness increases RTI risk in young children through micronutrient depletion, and immune stress, yet data on post-diarrhea RTI burden in LMICs are limited. We determined the prevalence and risk factors of RTI within three months following medically-attended diarrhea (MAD) in children aged 6-35 months enrolled in seven EFGH country sites in Asia, Africa and South America. The EFGH study prospectively enrolled children aged 6-35 months with MAD in selected health facilities during a 24-month period from 2022 to 2024 and followed them for three months. RTI was defined as cough or difficulty breathing and the presence of one of the following symptoms at any scheduled or unscheduled visit during follow-up: stridor; fast-breathing; oxygen saturation <90%; or chest indrawing. The period prevalence and 95% confidence intervals of RTI were calculated, and correlates of RTI were assessed using modified-Poisson regression. From June 2022 to August 2024, 9,476 children aged 6-35 months presenting with MAD in the EFGH study sites were screened: 9,116 (96.2%) included in the current study. Nearly half were female (46.7%), and median age was 15 months. Overall, 48.5% received all age-appropriate vaccines, and 87.6% received the pneumococcal vaccine, with significant variation across countries. Nearly one-quarter of children were stunted, 17.2% wasted, and 21.9% underweight. RTI occurred in 3.8% of children during the three-month follow-up, mostly within the first month. Higher prevalence of RTI occurred among children aged 12-23 months (8.7%), those undernourished (16.1%), unvaccinated (4.0%) or living in poor sanitation settings (4.1%). While children who received all age-appropriate or pneumococcal vaccinations had a lower crude prevalence of RTI, these associations were not statistically significant after adjusting for age, sex and study site. RTI was infrequently observed in the three months following MAD presentation, with significant variability by site and with the highest prevalence in Malawi. RTI risk was highest in 12-23-month-olds and among children with undernutrition, and those living in poor sanitation conditions.
Unegbu, U. L.
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Background: Nigeria bears one of the highest maternal mortality burdens globally, with skilled birth attendance (SBA) remaining critically low in many regions. Understanding the independent determinants of SBA is essential for designing targeted interventions. Methods: This cross sectional study analyzed 21,465 births from the 2018 Nigeria Demographic and Health Survey (NDHS), a nationally representative household survey using stratified two stage cluster sampling. SBA was defined as delivery attended by a doctor, nurse, midwife, or auxiliary midwife. Multivariable logistic regression was used to estimate adjusted odds ratios (aOR) with 95% confidence intervals for the associations between SBA and maternal education, household wealth, place of residence, geopolitical region, maternal age, parity, and antenatal care (ANC) utilization, after accounting for confounding. Results: The overall prevalence of SBA was 44.9%. In the fully adjusted model, higher education (aOR = 7.01, 95% CI: 5.68-8.67), richest wealth quintile (aOR = 6.27, 95% CI: 5.27-7.46), and attending [≥]4 ANC visits (aOR = 3.80, 95% CI: 3.51-4.11) were the strongest independent predictors of SBA. Regional inequalities were pronounced, with SBA prevalence ranging from 17.7% in the North West to 85.6% in the South West. Crude effect estimates for education and wealth were substantially attenuated after adjustment, indicating large confounding by correlated socioeconomic factors. Conclusions: Maternal education, household wealth, ANC utilization, and geopolitical region are independent determinants of SBA in Nigeria. Scaling up ANC programs represents the most immediately actionable intervention, while long term gains require investment in girls' education and wealth equity. Targeted strategies for the northern regions are urgently needed. Keywords: skilled birth attendance, maternal mortality, Nigeria, DHS, antenatal care, logistic regression, health equity
Mogeni, P.; Ochieng, J. B.; Kariuki, K.; Rwigi, D.; Atlas, H. E.; Tickell, K. D.; Aluoch, L. R.; Sonye, C.; Apondi, E.; Ambila, L.; Diakhate, M. M.; Singa, B. O.; Liu, J.; Platts-Mills, J. A.; Saidi, Q.; Denno, D. M.; Fang, F. C.; Walson, J. L.; Houpt, E. R.; Pavlinac, P. B.
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BackgroundThe Toto Bora trial tested whether a course of azithromycin reduced rates of re-hospitalization or death in the 6 months following hospitalization among Kenyan children. We hypothesized that azithromycin would reduce enteric bacteria and increase carriage of macrolide resistance in the subsequent 3 months. MethodsKenyan children (1-59 months) hospitalized and subsequently discharged for non-traumatic conditions provided fecal samples before and 3 months after randomization to a 5-day course of azithromycin or placebo. Quantitative PCR identified enteropathogens and AMR-conferring genes in fecal samples. Generalized estimating equations assessed the impact of the randomization arm on pathogen and resistance gene detection, accounting for baseline presence and site. ResultsAmong 1,393 baseline stools, 12.4% had at least one bacterial enteropathogen, 94.7% had at least one macrolide-resistance gene, and 92.6% had at least one beta-lactamase-resistance gene identified. At month 3, children randomized to azithromycin had a 6.1% higher likelihood of carrying a macrolide resistance gene compared to placebo (adjusted prevalence ratio [aPR], 1.06; 95% CI, 1.04-1.08; P<0.001). Specifically, azithromycin randomization was associated with a higher relative prevalence of erm(B) (aPR, 1.09 [95% CI, 1.04-1.15]; P=0.001), erm(C) (aPR, 1.23 [95% CI, 1.14-1.31]; P<0.001), msr(A) (aPR, 1.14 [95% CI, 1.04-1.25]; P=0.007), and msr(D) (aPR, 1.07 [95% CI, 1.03-1.11]; P=0.001). There was no difference in overall bacterial pathogen prevalence (18.9% vs 17.3%) between randomization arms, but a slightly lower proportion of children had Shigella after randomization in the azithromycin arm (3% vs. 5%, aPR, 0.79 [95% CI, 0.62, 1.01]; P=0.063). InterpretationAzithromycin at hospital discharge was associated with higher carriage of macrolide-resistance-conferring genes in the post-discharge period compared with placebo, without significant declines in enteric pathogen carriage other than modest changes to Shigella. The potential benefits and risks of empiric azithromycin need to be considered, as children are increasingly exposed to this broad-spectrum antibiotic.
MacLean, E. L.; Ma, T. T.; Chuong, L. H.; Minh, K. H.; Hoddinott, G.; Pham, Y. N.; Tiep, H. T.; Nguyen, T.-A.; Fox, G.; Nguyen, N. T.
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Introduction Improved diagnostics are needed for people at risk of tuberculosis, especially adolescents. Tongue swab (TS) molecular testing has emerged as a promising strategy for tuberculosis diagnosis. We evaluated diagnostic accuracy and acceptability of Xpert MTB/RIF Ultra (Xpert) using TS samples for tuberculosis detection among adolescents. Methods We conducted a cross-sectional diagnostic accuracy study with consecutive recruitment in Vietnam. Adolescents aged 10-19 who were recommended to undergo investigation for tuberculosis and had not received tuberculosis treatment in the past years were eligible. Participants provided TS and sputum samples and completed a structured survey regarding sampling experiences. TS was tested on Xpert, with sputum tested on Xpert and liquid culture. We utilised a composite reference standard of a positive result on sputum Xpert or sputum culture to define disease status. Sensitivity, specificity, and diagnostic yield were calculated for TS Xpert. Results From July to December 2025, we enrolled 225 adolescents from Can Tho and An Giang provinces in southern Vietnam. Fewer than half (96/225, 43%) the participants exhibited a tuberculosis -like symptom, and the majority (157/225, 70%) were close contacts of a person recently diagnosed with tuberculosis. TS were collected from all adolescents, while 116 (52%) could provide mucopurulent sputum. Tuberculosis prevalence was relatively low (12/225, 5.3%). TS Xpert sensitivity (90% CI) and specificity (90% CI) were 58.3% (35.6, 78.0) and 99.5% (97.9, 99.9), respectively. Diagnostic yield among all diagnosed was 58.3% (7/12). TS sampling was highly acceptable to adolescents; the short time and simplicity of collecting TS were considered favourably. Conclusions The sensitivity and diagnostic yield of TS Xpert was relatively low among adolescents recommended for tuberculosis investigation, which includes asymptomatic individuals who may not provide high quality sputum. Specificity was excellent, and everyone could provide a TS. TS high acceptability indicates it remains a promising sample for diagnostic algorithms.
Mitiku, D. k.; Gessesse, A. D.; Derse, T. K.; Lidetu, T. k.; Asgai, A. S.; Kelkay, J. M.
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BackgroundZero-dose children, defined as those who have not received the first dose of a diphtheria-tetanus-pertussis-containing vaccine (DPT1), are a key indicator of inequitable access to immunization services. Nigeria remains one of the largest contributors to the global burden of zero-dose children. This study estimated the prevalence of zero-dose children aged 12-23 months and identified individual-and community-level determinants using the 2024 Nigeria Demographic Health Survey (NDHS). MethodsA secondary analysis of cross-sectional analysis was conducted using data from 4,711 children aged 12-23 months in the 2024 NDHS kids recode dataset. A multilevel mixed-effects logistic regression model was fitted to account for the hierarchical structure of the data. Four models were compared: null, individual-level, community-level, and combined models. Adjusted odds ratios (AORs) with 95% confidence interval (CI) were used to identify significant determinants at p<0.05. ResultsThe weighted prevalence of zero-dose children was 37.3% (95% CI: 35.1-39.6%). Significant factors included birth order, maternal age, maternal occupation, parental education, household wealth, antenatal attendance, postnatal care utilization, place of delivery, religion, distance to health facilities, and geographical region. Children whose mothers had higher educational attainment, attending antenatal care, deliver in the health facilities, and received postnatal care were significantly less likely to be zero-dose status. Conversely, children from poorer households, those facing distance barriers to health facilities, those belongings to Muslim and traditional religion group and those residing in certain geographical regions had higher odds of zero-dose children, with significant regional variations observed. Conclusionzero-dose vaccination remains highly prevalent in Nigeria and is strongly influenced by socioeconomic disadvantage, maternal healthcare utilization, religion, and regional inequities. Strengthening integrated maternal and child health services and improving access in underserved regions are essential to achieving equitable vaccination coverage.
Mandal, S.; Rade, K.; Singh, A.; Nair, S. A.; Sahu, S.
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Background Tuberculosis (TB) remains a critical public health challenge, with two-thirds of the global TB burden in ten Asian countries. Social vulnerabilities, comorbidities, health inequity, multi-dimensional poverty, malnutrition, and barriers to healthcare access continue to fuel TB epidemic. Inability to detect asymptomatic and sub-clinical TB, combined with passive approach in service delivery and overreliance on smear microscopy, leads to delayed diagnosis, a substantial burden of undetected cases, and continuing TB transmission in the communities. In such a context, the introduction and scale-up of active case-finding approaches - including community-based TB screening using highly sensitive screening tools and novel rapid diagnostics - becomes a strategic priority to interrupt transmission. The growing availability of multiple screening and diagnostic options makes evidence-based decision-making increasingly complex. Methods To estimate the potential epidemiological impact and cost implications of scaling up TB diagnostics and community-based screening in ten high-burden Asian countries, we constructed a mathematical model and evaluated multiple intervention scenarios. We then assessed and compared four service delivery models: 1) digital ultraportable chest x-ray (UPCXR) & Xpert/Truenat in community, 2) digital UPCXR in community and Xpert/Truenat at health facilities, 3) digital UPCXR in community and near point of care (nPOC) at health facilities, 4) nPOC in community & Xpert/Truenat at health facilities - for total investment required and projected health benefits for their cost-effectiveness. Results and conclusions The modelling study indicated that strengthening health facility capacity (with enhanced TB screening, expanded molecular diagnostics, reduced loss to follow-up, private sector standard of care, leading to increased treatment coverage & quality of active disease treatment and reduced post-treatment relapse, scale-up of TB preventive treatment (TPT), and provision of nutritional support to 80% of TB patients and their household contacts) can significantly reduce TB incidence and mortality; however, community-wide mass screening remains essential to achieving TB elimination targets . Targeted screening of vulnerable populations demonstrated greater cost-effectiveness than untargeted screening approaches. Achieving the End TB goals will ultimately require an effective TB vaccine with high population-level coverage. AI-enabled digital UPCXR-based screening combined with Xpert/Truenat testing at the community level demonstrated maximum epidemiological impact potential, while the most cost-efficient model is Digital UPCXR in the community combined with nPOC testing at health facilities. An investment of USD 12.7 billion over the next five years in community-level implementation of digital UPCXR and molecular diagnostics could avert an additional 9.8 million TB cases and 1.9 million deaths across ten Asian countries over a ten-year horizon.
Wiriyaprom, R.; Ngasaman, R.; Kaewnoi, D.; Prachantasena, S.
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Foodborne illness is a significant public health concern worldwide. Shiga toxin-producing Escherichia coli and Campylobacter species are recognized as important zoonotic bacterial pathogens contributing to human infections through the food chain, particularly via foods of animal origin. Although goat meat is in high demand in the southern region of Thailand, studies on foodborne pathogens in this livestock species remain limited. The current study aimed to (i) determine the antimicrobial susceptibility of Campylobacter spp. and STEC isolated from goats, and (ii) analyze the genetic relationships among Campylobacter spp. And E. coli O157 isolates obtained from different sources. Campylobacter jejuni and C. coli isolates were characterized based on sequences of seven housekeeping genes using the Achtman multilocus sequence typing scheme. For E. coli O157:H7, core genome multilocus sequence typing analysis was performed using whole-genome sequencing data. Genetic diversity was observed among C. jejuni, whereas a clonal population structure was detected in C. coli and E. coli O157:H7. Overlapping genetic characteristics were observed between C. jejuni isolates from goats and those previously reported in livestock and humans in Thailand. Among Campylobacter species, resistance to fluoroquinolones, including ciprofloxacin and nalidixic acid, was observed, whereas resistance to fosfomycin was most frequently detected in Shiga toxin-producing E. coli. Tetracycline-resistant isolates were identified in both Campylobacter species and Shiga toxin-producing E. coli at moderate levels. A multidrug-resistant pattern was observed only in C. coli, whereas no multidrug-resistant C. jejuni or Shiga toxin-producing E. coli isolates were detected. These findings indicate that healthy goats may serve as potential reservoirs of zoonotic pathogens and antimicrobial resistance in southern Thailand, where goat meat is frequently consumed.