Transactions of The Royal Society of Tropical Medicine and Hygiene
◐ Oxford University Press (OUP)
Preprints posted in the last 90 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.
Podder, D.; Sonowal, H.; Saha, S.; Shah, B.; Ghosh, S.; Kumar, J.; Nag, A.; Chattyopadhyay, D.; Javed, R.; Rath, A.; Chakraborty, S.; Parihar, M.; Zameer, L.; Achari, R. B.; Nair, R.
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IntroductionSolitary plasmacytomas (SP) are rare neoplasm of localised proliferation of clonal plasma cells. It can be classified based on site of involvement and bone marrow involvement. It is an indolent disease in the majority of patients. Primary modality of treatment is radiotherapy and surgical excision. Materials and methodsThis was a retrospective audit of SP who were treated and followed up at a tertiary care center in eastern India from January 2012 to December 2025. Patients who has solitary plasma cytoma with more than 10% plasma cells, POEMS syndrome, have been excluded from analysis. ResultsWe identified 46 patients of SP. The median age of the studied population was 53 years (23-75 years). Males were more commonly affected than females (M:F=2.2:1). Most common chief complaints were bony pain (67.4%). SBP was seen in 39 (84.8%) cases whereas SEP was seen in 7 (15.2%) cases. Vertebra was the most common site of involvement (61.4%). Median M band concentration 0.24 g/dL (0.1 to 1.95 gm/dL). IgG was the most common isotype accounting for 60.6% cases. Six cases (13%) had minimal bone marrow involvement. The majority of the patients received local radiotherapy (89.1%). With a median follow up of 5.4 years (95% CI: 1.8 - 9.0), median OS was not reached, median PFS was 9.22 years (95% CI: 5.8-12.6), median time to next treatment (TTNT) was 9.86 years (95% CI: 6.8 - 12.9). ConclusionSolitary plasmacytoma commonly affects young males. Bones are more commonly affected than extramedullary sites. SP has a lower rate of progression and excellent prognosis when treated with local radiotherapy.
KARIUKI, H. W.; Nyasore, S. M.; Muthini, F. W.; Mwangi, P. W.; Mwandi, J. M.; Makazi, P.; Mureithi, M. W.; Bulimo, W. D.; Wango, T. J. L.; Wanjala, E.; Mckinnon, L.; Njaanake, H. K.
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Background Urogenital schistosomiasis (UGS), caused by Schistosoma haematobium (S. haematobium), disproportionately affects women in sub-Saharan Africa and can lead to haematuria, anaemia, and urinary tract morbidity. Data on the prevalence in women of reproductive age remains limited in contrast to infection among school-aged children in Kenya. This study assessed the prevalence of UGS and its socioeconomic determinants among women in Kilifi County, Kenya. Methods: Urine samples (20-50 mL) were collected from each participant over three consecutive days. Day-one samples were tested for haematuria, proteinuria, nitrites, leukocytes, and pregnancy using dipsticks. On the other hand, 10 mL of urine was examined for S. haematobium eggs via urine filtration on all three days. Results: A total of 599 women aged 15-50 years were enrolled, with complete data available for 336. The mean age was 33 years; 57.7% were <35 years. Most participants were from rural Magarini Sub-county (63%) and engaged in crop farming (62.5%). Primary education was the highest level attained by 59.8% of participants. Frequent contact with stagnant water was reported by 92%. The overall prevalence of S. haematobium infection was 13.7% (95% CI: 10.2-17.8), higher in Magarini (14.9%) than in Rabai (12.0%), though not statistically significant. Younger age, primary education, and frequent water contact were associated with higher infection rates; however, after adjustment for covariates, haematuria showed the strongest independent association with infection. Women with haematuria were 25.2 times more likely to be infected (OR: 25.24, 95% CI: 7.07-82.63, p < 0.001); multivariate analysis confirmed haematuria as the sole significant predictor (OR: 20.83, 95% CI: 5.45-79.57, p < 0.001). Conclusion: UGS prevalence among women in Kilifi County is substantial, with variation between sub-counties. Haematuria demonstrated the strongest independent association with infection and may serve as a simple, non-invasive diagnostic marker. These findings underscore the pressing need for the integration of UGS screening into the reproductive health services and targeted interventions. Authors Summary UGS, caused by the parasitic worm Schistosoma haematobium, is a neglected tropical disease and remains a major public health problem in sub-Saharan Africa. Although control programmes in Kenya primarily target school-aged children, women of reproductive age are frequently exposed through daily water contact and may develop chronic urinary and reproductive health complications. However, data on the infection burden among adult women are limited. In this study, we assessed the prevalence of urogenital schistosomiasis and associated risk factors among women aged 15-50 years in Kilifi County, Kenya. Urine samples were collected over three consecutive days and examined for parasite eggs and indicators of urinary tract disease. We found that urogenital schistosomiasis affected more than one in ten women in the rural sub-counties where the study was conducted. Haematuria was strongly associated with infection and remained the most reliable predictor after accounting for other social and behavioural factors. These findings demonstrate that UGS is an under-recognised health issue among women and highlight the potential value of simple urine-based screening tools. Integrating UGS screening into existing reproductive health services could improve early detection and contribute to more inclusive disease control strategies.
Hudu, S.; Uthman, K.; Katuala, Y.; Bello, I. W.; Mbuyi, Y.; Worku, D. T.; Mbelani, S. C.; Adjaho, I. I.; Gignoux, E.; Doumbia, C. O.; Ale, F.; Polonsky, J.
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BackgroundNigeria has experienced its largest recorded diphtheria outbreak since late 2022, centred on Kano State, where facility-based surveillance documented over 18,000 confirmed cases. The true community burden remains unknown. We conducted a population-based household survey to estimate community attack rates, mortality, vaccination coverage, and determinants of infection and death. MethodsWe performed a retrospective household survey (September-October 2024) using spatially randomised cluster sampling (65 clusters, ~15 households each; recall period January 2023 to interview). Survey-weighted analyses, multivariable logistic regression, and sensitivity analyses were used. FindingsWe enrolled 7,998 individuals from 1,068 households. The community attack rate was 1{middle dot}1% (95% CI 0{middle dot}7-1{middle dot}4), 4{middle dot}2 times (2{middle dot}7-5{middle dot}3) higher than facility-based estimates. The case fatality ratio was 8{middle dot}8% (1{middle dot}9-15{middle dot}6) overall and 21{middle dot}3% among children under five; two thirds of deaths occurred at home. Delayed care-seeking of four or more days was associated with markedly higher mortality (risk ratio 32{middle dot}6, 95% CI 2{middle dot}4-450{middle dot}0). Vaccination was strongly protective against death (vaccine effectiveness 57%, 95% CI 34-72%; E-value 4{middle dot}07). Among campaign-eligible children, routine EPI coverage was 58{middle dot}1% and campaign coverage was 52{middle dot}4%; 41{middle dot}9% (95% CI 39{middle dot}0-44{middle dot}9) of eligible children had no evidence of vaccination from either source. InterpretationCommunity diphtheria burden substantially exceeded facility surveillance estimates, with most deaths occurring outside the health system. Delayed care-seeking and low vaccination coverage were the main drivers of mortality, highlighting the need for improved community surveillance, decentralised care, and better-targeted vaccination.
Kyomuhangi, I.; Otabil, K. B.; Acheampong, A.; Ofori, D. K.; Kudzordzi, P.-C.; Nyarko, P.; Fronterre, C.; Cheke, R. A.; Basanez, M.-G.; Hawkes, F.
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Progress towards elimination of onchocerciasis transmission is evaluated using entomological and serological indicators. The latter assesses anti-Ov16 IgG4 seroprevalence in children aged <10 years. A seroprevalence of <0.1% suggests that ivermectin Mass Drug Administration (MDA) can be stopped and post-treatment surveillance initiated, according to World Health Organization (WHO) guidelines. Surveillance of populations living in close proximity to vector breeding sites and first-line villages may mask spatial transmission heterogeneity. We mapped anti-Ov16 seroprevalence within a 25-km radius around a known Simulium damnosum s.l. breeding site in Asubende, Ghana, to assess its spatial patterns and their implications for serosurveillance. A cross-sectional survey was conducted in September-November 2024 in 30 settlements. Individuals aged [≥]3 years were recruited through convenience sampling. The Ov16 rapid diagnostic test (RDT) using dry blood spots was used to estimate overall and site-level seroprevalence. Generalized additive models were used to assess seroprevalence trends versus distance from the breeding site. Among 2,479 participants with valid RDT results, overall seroprevalence was 10.0% (95% CI: 8.9%, 11.3%) and increased with age. Seroprevalence varied across sites (0-24.4%) and declined with increasing distance from the breeding site. Among 584 children <10 years old, seroprevalence was 1.5% (95% CI: 0.7%, 2.9%). Adjusting for RDT sensitivity and specificity, seroprevalence in this age-group was 0.7%, (95% CI: 0%, 2.4%). Seropositive children were detected up to 18 km from the breeding site, but none were identified at it. The distance-related decrease in overall seroprevalence is consistent with spatial patterns in vector abundance at Asubende and implies higher cumulative exposure near the breeding site. The small number of children tested limited inference in this WHO target age-group. Detection of seropositive children away from, but not at, the breeding site highlights limitations of surveillance focused on first-line villages and supports broader spatial sampling to strengthen evidence for stop-MDA decisions. Author summaryAfter decades of onchocerciasis control using ivermectin, many countries hope to demonstrate that they have interrupted transmission of this vector-borne parasitic disease using serological surveys. It is unclear whether exposure to infection is spatially clustered around the riverine breeding sites of the blackfly vectors and therefore whether this is where serosurveillance should focus. To address this, we collected dried blood spots from 2,480 consenting participants aged 3-96 years old from 29 communities within a 25-km radius of a known blackfly breeding site in Asubende, Ghana. A rapid diagnostic test was used to test the blood spots for antibodies to the Onchocerca volvulus parasite. We found that overall seropositivity declined with increasing distance from the breeding site, which suggests that cumulative exposure is higher near the breeding site, where vector population is also high. However, seropositivity in children (3-10-year-olds, n= 584), which is indicative of recent transmission, was spatially distributed across the study area and found up to 18 km from the breeding site. These findings are relevant to serosurveillance sampling strategies intended to detect low levels of transmission, which could miss peripheral evidence of ongoing transmission if they are focussed at breeding sites and those villages closest to them.
Luc, G.; Keita, M.; Diarra, B.; Djekornonde, P.; Zakaria, F. A.; Sacher, A.; Wassonguema, B.; Bazongo, B.; Akoina, M.; Issa, M. G.; Abderamane, M.; Biaou, C.; Seyvet, T.; Abakar, A.; Moutede, V.; Heylen, C.; Bentley, M.; Jost, C.; Young, H.; Bechir, M.; Abakar, M. F.; Marshak, A.; Null, C.; Osman, A. M.
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Background: Child acute malnutrition remains persistently above emergency thresholds in Chad's Sahelian drylands, with a predictable, but rarely recognized, dry season peak linked to declining pasture and livestock productivity, reduced milk availability and heightened exposure to zoonotic infections. Humanitarian responses remain largely reactive and treatment-focused, with limited evidence on preventive strategies that address drivers embedded in local livelihood systems. We evaluated the effectiveness and return on investment (ROI) of an integrated livestock management intervention designed to prevent the dry-season peak of child acute malnutrition in pastoral and agro-pastoral communities in Chad. Methods: We conducted a cluster-randomised controlled trial in Kanem and Barh-El-Gazel provinces, Chad. Seventy-six villages were randomised (1:1) to intervention or control. Eligible households had at least one child aged 6-59 months and access to milking livestock during the dry season. The intervention (December 2024-June 2025) combined livestock feed supplementation to sustain milk production near households during the dry season, household-level zoonotic risk mitigation, and nutrition counselling. Primary outcomes were the prevalence of global acute malnutrition (GAM) and severe acute malnutrition (SAM) at the dry-season peak (May 2025), assessed in a prespecified random subsample of 52 clusters. All 76 clusters were assessed post-peak (July 2025). Analyses followed an intention-to-treat approach using mixed-effects models. A societal ROI analysis was conducted over six months with projections to 24 months. Findings: At the dry-season peak, 821 children 6-59 months from 521 households were assessed across 52 villages. GAM prevalence was 22.2% in intervention villages versus 47.4% in controls (adjusted OR 0.29 [95% CI 0.18-0.49]; p<0.001), and SAM prevalence was 4.4% versus 19.4% (adjusted OR 0.17 [0.08-0.37]; p<0.001). Intervention households had higher daily milk availability (+588 mL per household; p<0.001), and children consumed more milk (+102 mL per day; p=0.008). Odds of self-reported diarrhoeal disease and acute respiratory infection were substantially lower among children in intervention villages (aOR 0.21 [0.10-0.44] and 0.22 [0.11-0.46], respectively). Post-peak, women's dietary diversity increased (aOR 3.68 [1.90-7.13]), alongside reduced workload, lower household food insecurity and distress livestock sales, improved livestock condition, and a benefit-cost ratio of 5.40 at six months, rising to 16.40 at 24 months. Interpretation: Protecting livestock productivity and sustaining children's access to milk while reducing zoonotic exposure during the pastoral lean season effectively prevents seasonal peaks of child acute malnutrition. This integrated anticipatory action and One Health livelihood-based approach offers a scalable, dignifying, high-return lifesaving preventive model for pastoral and agro-pastoral humanitarian settings.
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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BackgroundAffecting 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. MethodsWe 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. Results1,815 (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). ConclusionIron-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. TRIAL REGISTRATION clinicaltrials.gov IdentifierNCT01001871. Registered 27/10/2009, http://www.ClinicalTrials.gov/NCT01001871.
Mangal, T. D.; Colbourn, T.; Phillips, A. N.; Mfutso-Bengo, J.; Mphamba, P.; Mohan, S.; Murray-Watson, R.; Nkhoma, D.; Janouskova, E.; She, B.; Revill, P.; Hallett, T. B.
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BackgroundPreventive chemotherapy targeting school-aged children has substantially reduced schistosomiasis morbidity, however, a key strategic tension remains between sustaining morbidity control and pursuing transmission elimination, particularly in settings characterised by heterogeneous transmission dynamics and persistent adult infection reservoirs. We developed a health system-integrated transmission and economic evaluation framework to identify optimal age-targeting and district-level prioritisation, providing a basis for determining when elimination-focused approaches offer advantages over morbidity reduction alone. MethodsThe Thanzi la Onse individual-based model was used to evaluate alternative age-targeted mass drug administration (MDA) strategies for Schistosoma haematobium and Schistosoma mansoni across all 32 districts of Malawi from 2024-2050. Strategies included treatment of school-aged children (MDA-SAC), pre-school and school-aged children (MDA-PSAC+SAC), and community-wide treatment (all ages). Health outcomes included person-years with any infection (PY), disability-adjusted life years (DALYs), probability of elimination (defined as reaching <2% prevalence of infection in all ages). The cost-effectiveness was evaluated using incremental cost-effectiveness ratios (ICERs), net health benefit (NHB), and by quantifying the maximum costs available for implementation, using a cost-effectiveness threshld for Malawi of 88 USD per DALY averted. FindingsIn the absence of MDA, the majority of the infection burden over 2024-2050 would be concentrated in adults aged 15 years and older (219.6 million person-years [PY], 95% CI 215.4-223.4), compared with 72.8 million PY (95% CI 71.5-74.3) among school-aged children (SAC) and 25.5 million PY (95% CI 25.1- 26.2) among preschool-aged children. Annual MDA-SAC would avert approximately 18.0 million DALYs (95% CI 17.6-18.4) between 2025 and 2050 and would be highly cost-effective nationally (ICER 4.76 USD/DALY, 95% CI 4.47-4.95). Across districts, ICERs were highly variable; 25 of 32 districts were cost-effective in [≥]90% of runs and 29 of 32 in [≥]50% of runs. Expanding treatment to include preschool-aged children (MDA PSAC+SAC) would produce modest additional gains (additional 44,500 DALYs averted) but with substantially higher costs (national ICER 606 USD/DALY, 95% CI 472-695), being dominated in 22 districts and cost-effective only in the high-burden Likoma district. Community-wide MDA would achieve elimination for both species in all districts by 2030 and avert a further 98,000 DALYs; nationally it would be cost-saving relative to PSAC+SAC although outcomes were heterogeneous, with this strategy being cost-saving in 11 high-prevalence districts (2023 prevalence range 13.7 - 41.5%) but dominated (in >80% of model runs) in 16 others. Threshold analyses of maximum implementation costs indicated substantial cost margins in high-burden districts, with cost-effectiveness maintained up to approximately 25-38 USD per treatment. InterpretationThe choice of schistosomiasis strategies should depend on whether programmes prioritise short-term morbidity reduction or long-term elimination, as well as the local disease burden and the prevailing cost of service delivery. Integrating district-level transmission dynamics with opportunity-cost-based economic evaluation reveals when broader coverage is justified and provides a framework for designing fiscally grounded elimination pathways in heterogeneous endemic settings.
Chali, W.; Ejigu, L. A.; Atele, T.; Sisay, S.; Jebessa, G.; Habtamu, G.; Abdo, M.; Shimelash, A.; Demisse, M.; Bezabih, M. K.; Nibret, D.; Gizat, A.; Getachew, K.; Abi, K.; Zeleke, A. J.; Getnet, B.; Solomon, Z.; Bayena, T.; Endale, T.; Dechasa, M.; Massebo, F.; Kassa, F. A.; Challi, S.; Mamo, H.; Drakeley, C.; Bousema, T.; Tadesse, F. G.
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In co-endemic regions, mixed Plasmodium vivax (Pv) and Plasmodium falciparum (Pf) infections are commonly reported. How mixed species infections compare to single species infections in terms of parasite densities and transmission to mosquitoes is incompletely understood. Parasitemia, gametocytemia, and mosquito infectivity were evaluated among Pv mono-infections (n=284), Pf mono-infections (n=150), and mixed-Pv-Pf infections (n=77) recruited at four Ethiopian health facilities. Parasitemia and gametocytemia were quantified in patient blood samples by qPCR. Mosquito infectivity was assessed using direct membrane feeding assays (DMFA), with Plasmodium species confirmation by PCR. Pf gametocyte prevalence was lower in mixed-infections (64.5%, 49/76) compared with mono-infections (91.8%, 135/147); among gametocyte-positive parasite carriers gametocyte density was also lower in mixed-infections (p<0.001). Pv gametocyte prevalence was similar in mono- and mixed-infections despite lower asexual parasite density in mixed infections (p<0.001). Statistically significant positive correlations between asexual parasitemia and gametocytemia were observed in mono-infections (p<0.001), but not in mixed-species infections (p=0.120 for Pv; and p=0.570 for Pf). Transmission to mosquitoes was high across infections and infection combinations. Among infectious Pv-Pf parasite carriers, 56.3% (27/48) transmitted both species, often with both species being transmitted to individual mosquitoes. The associations between (species specific) gametocyte density and mosquito infection rates was unaffected by the concurrent presence of the other Plasmodium species. Although mixed-species infections may have different parasite and gametocyte densities compared to mono-infections, we observed no evidence for competition between species in mosquitoes. Because mixed infections are often undetected, they represent a hidden risk for sustaining malaria transmission. Author SummaryMalaria remains a major public health challenge in Ethiopia, where Plasmodium vivax and Plasmodium falciparum often occur together in the same patient. While mixed-species infections are common, little is known about how they compare to single-species infections in terms of parasite levels and transmission to mosquitoes. In this study, we examined patients with P. vivax, P. falciparum, or mixed infections across four health facilities. We measured parasite and gametocyte densities in blood samples and tested whether patients could infect mosquitoes. We found that P. falciparum gametocyte levels were lower in mixed infections compared to single-species infections, while P. vivax gametocyte levels were similar regardless of infection type. Importantly, patients with mixed infections were still highly infectious to mosquitoes, and many transmitted both parasite species simultaneously. These findings show that mixed infections, which are often missed by routine diagnosis, can contribute substantially to malaria transmission. Recognizing and addressing mixed-species infections is therefore critical for malaria control and elimination efforts.
Hernandez, P.; Mata, C.; Lares, M.; Moran, M.; Gonzalez, Z.; Catarino, E.; Ramos, Y.; Varela, A.; Fautsch-Macias, Y.; Funnell, G.
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To provide adequate care to children with acute malnutrition, different management protocols have been in use, including the WHO standard guideline and a simplified protocol. The latter, used in Venezuela since 2020, has adopted three simplifications: 1) Expanded criteria for treatment admission; 2) Use of a single treatment product; 3) Simplified dosage: use of 2 sachets per day to treat SAM cases and 1 sachet per day to address MAM cases, regardless of weight. Our study compares the effectiveness, length of stay and programmatic costs of the simplified protocol and the WHO standard guideline in addressing acute malnutrition in children aged 6-59 months in Venezuela from February to August 2024. A total 229 children were enrolled in a prospective cohort study. Monitoring was continuous up to 16 weeks of treatment, evaluating key indicators including weight gain, recovery time, survival, recovery and default rates, number of sachets of RUTF consumed and implementation costs. Baseline characteristics were similar between cohorts, with most cases being moderate in both the standard (90.9%) and simplified (86.6%) cohorts. Both protocols demonstrated similar anthropometric improvements and recovery trajectories throughout follow-up, with no significant differences (p > 0.05). However, the simplified protocol showed higher recovery rates overall for MAM and SAM (70.1% vs 59.4%, p=0.031), although default rates remained high in both protocols (24.8% in the standard protocol vs. 18.7% in the simplified protocol). The simplified protocol presented reduced costs by 15% ($133 vs $157 per recovered child). These results suggest that the simplified protocol, using a single product and an adapted dosage, is as effective as the standard protocol for treating children with acute malnutrition in Venezuela. The findings support wider implementation of the simplified protocol particularly in resource-limited settings. Further research is needed to optimize protocols and improve adherence to reduce default rates.
Sharkey, T.; Nyombayire, J.; Parker, R.; Ingabire, R.; Umuhoza, C.; Bizimana, J.; Mukamuyango, J.; Unyuzimana, M. A.; Mazzei, A.; Tichacek, A.; Allen, S.; Karita, E.; Wall, K. M.
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Reproductive tract infections (RTI) are associated with adverse outcomes in pregnant African women. However, many diagnostic strategies are unaffordable or perform poorly. Here, we assess RTI prevalence and predictors of chlamydia/gonorrhea (CT/NG) in pregnant women reporting vaginal discharge and the performance of our previously published CT/NG risk algorithm in this population versus Rwandan National Guidelines (RNG). From 2017-2020, free sexually transmitted infections (STI) services were provided to residents in Kigali, Rwanda. Medical history and gynecologic examination were done. Laboratory assessments included HIV; syphilis; microscopy for trichomoniasis, bacterial vaginosis (BV), and candida; and PCR for CT/NG. Eighty-seven pregnant women received STI services. Prevalence was 28% for CT/NG, 15% for trichomoniasis, 24% for BV, 39% for candida, and 79% for any RTI. Predictors of CT/NG were age <=25 (adjusted prevalence odds ratio [aPOR]=4.92; 95% confidence interval [CI]: 1.52-15.90; p=0.008), inconsistent condom use (aPOR=4.86; 95%CI: 0.98-24.10; p=0.053), absence of candida (aPOR=4.23; 95%CI: 1.13-15.82; p=0.032), and endocervical inflammation/discharge (aPOR=4.91; 95%CI: 1.40-17.20; p=0.013). Our algorithm outperformed the 2019 and 2024 RNG (sensitivity: 92% versus 46% and 35% respectively). Pregnant women seeking STI services had high RTI prevalence. Our algorithm performed well. Algorithms tailored for pregnant women and including male partner risk factors should be explored.
McCarthy, W. C.; Crain, C. J.; Olubodun, T.; George, I. A.; Birk, S. L.; Ekpo, U. F.; Mogaji, H.; Leng, H. T.; Kathiresan, R.; Salas, C.; Sekou, M. H.; Soneye, I.; Adeniyi, M. A.; Beaubrun, J.; Nwosu, K. O. S.; Oludolamu, A.; Kafil-Emiola, M.; Okesola, B. B.; Koether, P. J.; Simbassa, S. B.; Shah, N.; Ngai, M. K.; Oluwanifemi, O. B.; Efosa, I.; Hassan, A. E.; Fagbohun, V.; Oladokun, B. D.; Cannon, C.; Oncho, F.; Rehman, M.; Adeola, A.; Stella, A. J.; Abiodun, A.; Naimot, K.; Adeola, S. T.; Adelakun, O.; Copeland, T.; Amao, D.; Shokeen, V.; Kothari, A.; Tebo, K. K.; Lee, J.; Prakash, M.
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BackgroundUrogenital schistosomiasis is a major cause of preventable morbidity, primarily in rural, resource-limited regions. After decades of mass drug administration, changing epidemiologic landscapes, and ongoing resource limitations, test-and-treat models may be necessary to meet elimination goals. However, diagnostic capacity remains centralized and laboratory-dependent, and community-led, contextually adapted implementation strategies remain poorly defined. This study describes the accuracy and feasibility of a low-cost diagnostic toolkit and explores community-integrated implementation models. Methodology/Principal FindingsThis mixed-methods study enrolled 418 participants from five endemic sites near Oyan River Dam, Ogun State, Nigeria in July 2025. Urine samples underwent parallel analysis by community health extension workers utilizing the toolkit and by laboratory technicians using standard microscopy. The toolkit consisted of a reusable urine filtration device paired with a under-$2 paper microscope. Semi-structured interviews with community health extension workers and key informants were analyzed using the Consolidated Framework for Implementation Research. Prevalence was 27.5% (115/418). Community health extension workers demonstrated progressive improvement in diagnostic accuracy across five sequential communities (n=237), rising from 52.5% (95% CI 37.5-67.1) to 92.1% (79.2-97.3) over eight study days (Cochran-Armitage Z=3.08, p=0.002). Specificity improved from 53.6% to 96.3% (Z=3.00, p=0.003), final sensitivity reached 81.8% (52.3-94.9), and final Cohens kappa reached 0.803. In the hands of laboratory scientists, Foldscope microscopy achieved 91.0% sensitivity and 99.3% specificity. Conclusions/SignificanceCommunity-led diagnostic task-shifting for urogenital schistosomiasis control is accurate, feasible, and implementation-ready. Consolidated Framework for Implementation Research-guided analysis demonstrated strong end-user acceptability, with local ownership, collaboration, and trust-building as key implementation facilitators. This approach addresses diagnostic gaps in resource-limited endemic settings with relevance to other community health worker-led strategies. Author SummarySchistosomiasis is a parasitic infection that spreads through contact with freshwater and often goes undetected and untreated for years. Most common in sub-Saharan Africa, the disease damages the bladder and genitourinary tract, increasing risk of infertility, bladder cancer, and HIV transmission. It is most prevalent in rural communities where the snail intermediate host thrives in local water sources used daily for fishing, farming, and bathing. One such area is the Oyan River in Nigeria. Here, we found that barriers to diagnosis and treatment of the illness include distance and transportation. In this study, community health workers diagnosed their neighbors and community members using a low-cost toolkit: a <$2 / 2700 microscope, called the Foldscope paired with a small steel filter card we designed, called the SchistoFilter.. We enrolled 418 people across five villages along the Oyan River in Nigeria and trained eight community health workers to use this toolkit at the point of care. By the fifth community visite, they reached 92.1% accuracy. The study team interviewed community health workers and government officials to contextualize this approach, and they were enthusiastic: The tools can be used with confidence, the training is feasible, and what is most needed is a reliable supply chain and supportive oversight.
Polonsky, J.; Hudu, S.; Uthman, K.; Katuala, Y.; Evbuomwan, P. E.; Osman, H. J. O.; Sulaiman, A. K.; Adjaho, I. I.; Doumbia, C. O.; Gignoux, E.; Ale, F.
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BackgroundDuring Nigerias largest recorded diphtheria outbreak, hospital capacity in Kano State was rapidly overwhelmed. Medecins Sans Frontieres introduced home-based care (HBC) for patients with mild disease to prioritise facility-based care for severe cases. We assessed whether HBC was non-inferior to facility-based treatment in terms of mortality, sequelae, and household transmission. MethodsWe conducted a retrospective matched cohort study. Mild diphtheria cases treated between January 2023 and May 2024 were matched 1:1 by treatment modality (HBC or diphtheria treatment centre [DTC]) on sex, age group, vaccination status, and residence. Conditional logistic regression estimated the association between treatment modality and mortality, with robustness assessed through propensity score weighting, sensitivity analyses, and E-value computation. FindingsOf 990 sampled patients, 678 (367 HBC, 311 DTC) were enrolled (68{middle dot}5%). After adjustment, treatment modality was not independently associated with mortality (HBC vs. DTC: aOR 0{middle dot}40, 95% CI 0{middle dot}13-1{middle dot}30), with similar estimates across sensitivity analyses (E-value 4{middle dot}40). Clinical complications were the strongest predictor of death (aOR 23{middle dot}1, 95% CI 1{middle dot}73-307). Vaccination was protective (aOR 0{middle dot}28, 95% CI 0{middle dot}08- 0{middle dot}94) and treatment delay of four or more days increased mortality (aOR 4{middle dot}15, 95% CI 1{middle dot}23-14{middle dot}0). HBC was not associated with increased household transmission or long-term sequelae. InterpretationVaccination and early treatment, rather than care setting, were the main determinants of survival. When supported by clinical triage and structured follow-up, decentralised care can be used to manage mild cases during diphtheria epidemics in settings with constrained hospital capacity. FundingMedecins Sans Frontieres, West and Central Africa. Research in contextO_ST_ABSEvidence before this studyC_ST_ABSWe searched PubMed and Google Scholar for articles published between January 1, 2000, and February 28, 2026, using combinations of the terms "diphtheria", "outbreak", "home-based care", "outpatient", "ambulatory", "community care", and "decentralised care". We found no published studies evaluating any form of decentralised or home-based clinical management for diphtheria. The existing literature on diphtheria case management is confined to facility-based settings: outbreak reports from multiple affected countries describe hospital-based treatment with diphtheria antitoxin (DAT) and antibiotics, and a systematic review pooled epidemiological and clinical data from historical outbreaks. Decentralised care models have been evaluated for other epidemic-prone diseases, including a measles epidemic in the Democratic Republic of the Congo (DRC) where decentralised management reduced mortality among children, and Ebola virus disease outbreaks in DRC where decentralised treatment centres were piloted to improve geographic access, though with limited outcome data. No study has assessed whether patients with diphtheria can be safely managed outside hospital settings. Added value of this studyNo prior evaluation of home-based care for diphtheria has been published. Using a retrospective matched cohort design with 678 patients during the largest diphtheria outbreak in Africa in decades, we found no evidence that home-based care increased mortality, long-term complications, or household transmission compared with facility-based care, and acceptability was high among patients in both groups. The study also provides one of the largest datasets on household transmission of diphtheria in an urban epidemic setting, finding no evidence that home-based care increased secondary transmission, and showing that vaccination status of the index case was the main factor influencing spread within the household. Implications of all the available evidenceProvided that triage is reliable, antibiotics are started promptly, and a functioning referral pathway exists, mild diphtheria can be managed safely at home during large epidemics. This approach preserves limited hospital and DAT resources for patients with moderate or severe disease, shortens treatment delays, and is acceptable to patients. Given ongoing outbreaks across West and Central Africa and persistent DAT supply constraints, decentralised care warrants inclusion in epidemic preparedness.
Gupta, V.; Podder, D.; Saha, S.; Shah, B.; Ghosh, S.; Kumar, J.; Jacoby, A. P.; Nag, A.; Chattopadhyay, D.; Javed, R.; Rath, A.; Chakraborty, S.; Demde, R.; Vinarkar, S.; Parihar, M.; Zameer, L.; Mishra, D.; Chandy, M.; Nair, R.
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Waldenstrom macroglobulinemia (WM) is a rare indolent neoplasm characterized by presence of [≥] 10% lymphoid cells in BM that exhibit plasmacytoid or plasma cell differentiation that secretes an IgM monoclonal protein. This is a retrospective analysis of 89 patients of WM that describes the clinical and laboratory characteristics, treatment patterns and outcome of patients of WM. The median age of the entire cophort was 66 years with male predominance (67.4%). Most common presentations were symptoms pertaining to anemia (77.5%) and constitutional symptoms (33.7%). Median bone marrow lymphoplasmacytic cells were 41%. Positivity for MYD88 and CXCR4 mutations were seen in 81.8% and 2.4% cases. BR was the most common regimen used (52.8%). Overall response rates were seen at 87.8%. Median overall survival, progression free survival and time to next treatment is 8.49 years, 2.15 years and 3.88 years. BR regimen was associated with highest event free survival.
Filip, E.; Sovannaroth, S.; Kugler, A. M.; Brindle, H.; Ngor, P.; Chhun, B.; Ringwald, P.; Zhang, Z.; Rekol, H.
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Between 2015 and 2025, Cambodia reported a 99.9% decline in the number of cases of malaria. To aid acceleration of elimination, the National Center for Parasitology, Entomology and Malaria Control (CNM) implemented a package of interventions known as the Last Mile (LM) elimination program. The aim of this study was to determine the impact of the LM program on case numbers and evaluate the coverage of interventions. LM was rolled out between November 2020 and December 2023 in villages reporting a locally acquired case of Plasmodium falciparum or mixed infection with P. falciparum and P. vivax and included combinations of targeted drug administration (TDA), intermittent preventative treatment for forest goers (IPTf), active fever screening (AFS), the recruitment of a village or mobile malaria worker (VMW/MMW) and the top-up of insecticide-treated bed nets (ITN) depending on the vulnerability and receptivity of the village. A total of 103 full and 82 partial villages in seven provinces were included. Two rounds of TDA were administered, with a total of 10,678 individuals (67.6%) given during the first round and 9,678 (62.3%) during the second round. Coverage varied by province with none meeting the recommended threshold of 80%. IPTf was implemented each month among 35% (n=35) of full LM villages and 56% (n=42) of partial LM villages. A total of 11.7% (n=12) of full LM villages implemented AFS consistently on a weekly basis. Controlled interrupted time series showed no statistically significant difference in the number of malaria cases before and after the implementation of LM. Although we were unable to prove a statistically significant impact of LM, likely due to the small number of cases prior to LM, it is important to add to the limited evidence-based for Accelerator Strategies in countries approaching the elimination of malaria. Furthermore, findings from the feasibility and impact of individual interventions were used to change policy at the national level.
Vinoth, D.; kumar, A.; jenifer, E.
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ABSTRACT Background Dog bite injuries are a major yet largely preventable public health concern worldwide. They contribute significantly to morbidity, healthcare burden, and economic costs, particularly in emergency department .The present study aims to analyse the demographics and injury pattern of dog bite cases presenting to the emergency department of a tertiary care hospital in Chennai. Methods We conducted a cross-sectional study with dog bite injured participants attending the Causality from November 2025 to April 2026 data was collected using a structured tool including details on demographics (Age, Gender, Education) injury related characteristics , history of pure bite site of dog bite injury type, WHO bitten criteria and information to management etc. We used here non probability statistical analysis and age specific dog bite cases and independent variables were analysed using SPSS (2.0 version). Result A total of Two hundred sixteen dog bite cases were analysed in the study by period of 6 months The majority of participants were 172 (79.6%) were above 18 years and 44 (20.4) were below 18 year, 130 (60%) from rural areas and 86 (39.8%) from urban areas, 136 (63.0%) of Victims presented within a day of the bite, 61( 28.2) next day and 19 (8.8%) in after one week 66 (30.6) were bitten by own dog and 150(69.4%)were bitten by neighbour / friended dog. 124(57.4) were bitten by stray dog 92(42.6) bitten by pet dog. 117(54.2) were vaccinated dog and 99(45.8%) were not vaccinated .110(50.9) victims were injured by laceration. 26(12.0%) were injured by puncture wound.46(21.3) were injured by abrasion 10(4.6) were injured by avulsion 15(6.9%) were injured by crush injury. 156(72.2%) were had minor wound.45(20.8%) victims had moderate wound and 15(6.9%) victims had severe wound. 112(51.9%) victims were taken antibiotics.104(48%) were not taken antibiotics. 185(85.6%) victims received tetanus toxoid, 31(14.4%) were not received tetanus toxoid. CONCLUSION There is a high burden of dog bite injuries from stray dogs in India. Despite early hospital presentation in many cases gaps in first aid practices and rabies post exposure prophylaxis were evident and highlighting inadequate awareness. Key words Rabies immunoglobulin, Dog bite, WHO criteria, Anti rabies vaccine, stray Dog, wound
Lim, R. M. M.; Arinaitwe, M.; Babayan, S. A.; Nankasi, A.; AtuhAire, A.; Namukuta, A.; Mwima, N.; Pedersen, A. B.; WEBSTER, J. P.; Lamberton, P. H.; Clark, J.
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Background/aims The World Health Organization (WHO) aims to eliminate schistosomiasis as a public health problem (EPHP) across 78 endemic countries by 2030. However, for low-prevalence settings that reach EPHP, guidance on managing transmission to maintain EPHP or move towards Interruption of Transmission (IoT) is limited, partly due to insufficient evidence on drivers of resurgence. In Uganda, some communities inland from Lake Victoria have achieved EPHP for Schistosoma mansoni but not progressed to IoT. This study explored whether routine, short-range travel to the highly endemic lake could sustain transmission in these settings. Methods We conducted a cross-sectional study in five Ugandan villages ~5 km from Lake Victoria. Parasitological data were collected using Kato-Katz and Point-of-Care Circulating Cathodic Antigen tests, alongside questionnaires on lake travel from 585 individuals aged 1-91 years. A structural causal model estimated the total and direct effects of travel frequency, activity type, water contact duration, and drug treatment history on infection. Bayesian regression models and counterfactual simulations predicted infection under hypothetical interventions. Results Reaching IoT in low-risk villages may be undermined by habitual, short-range travel to high-risk sites, driven by the nature and duration of lake contact. Daily lake travel caused a 1.7-fold increase in odds of infection, while occupational activities caused a 3.4-fold increase compared with no lake activity. Counterfactual analysis showed that removing lake contact duration most reduced infection risk among moderate-frequency travellers, while daily travellers showed smaller changes, and some transmission persisted among individuals with little or no lake contact. Simulations demonstrated that modifying lake contact behaviours could reduce individual infection risk but had limited population-level impact. Conclusion These findings indicate that targeting only high-risk villages or individual behaviours is unlikely to achieve sustained, wide-spread IoT, underscoring the need for integrated control strategies that account for mobility, behaviour, and local transmission ecology.
Putney, N.; Sayyad-Hilario, J.; Ukawuba, I.; Grandesso, F.; Singh, S.; Safari, P. D.; Pothin, E.; Filippini, B.; Djovouna, E.; Diar, M. S. I.; Champagne, C.; Camacho, A.
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Background Seasonal malaria chemoprevention (SMC) is a malaria intervention in which antimalarial drugs are administered monthly to children under 5 years of age during the high-transmission season. In the district of Moissala in southern Chad, SMC has been implemented since 2013, with an interruption in 2019, resumption in 2020, and expansion to five rounds of treatment in 2021. Recent World Health Organization (WHO) guidelines allow countries to adapt the timing and number of SMC rounds to local transmission patterns, creating a need to identify optimal strategies for each setting. In this study, we used mathematical modeling for three primary purposes: 1) to estimate the effectiveness of SMC in Moissala from 2018 to 2023, 2) to assess the impact of changes to SMC strategies since 2018, and 3) to determine the optimal SMC strategy in Moissala. Methods and findings We adapted a compartmental, climate-informed malaria transmission model to represent malaria dynamics in the presence of SMC. The model incorporates temperature and rainfall data to capture how climate variability influences malaria transmission over time. It was calibrated to routine surveillance data on malaria cases in children under five years old from 2018 to 2023. Using the calibrated model, we simulated malaria cases under alternative scenarios, including the absence of SMC and variations in the number and timing of SMC rounds. These simulations were then used to estimate the overall effectiveness of SMC, assess the impact of past changes in SMC strategies, and identify the optimal strategy in Moissala. Between 2018 and 2023, SMC reduced malaria cases in children under five by 26% (95% credible interval: 21%, 31%) relative to a scenario without SMC, corresponding to an average of approximately 14400 cases averted each year. The interruption of SMC in 2019 led to an estimated increase of 13600 cases (95% credible interval: 11200, 15800), representing a 31% rise during the high-transmission season. Expanding from four to five SMC rounds in 2021 reduced cases by 7% relative to a four-round schedule, while starting the five-round schedule earlier in June rather than July led to an additional 5% reduction. Overall, the most effective strategy from 2018 to 2023 was a five-round schedule beginning in mid-June. Conclusions Seasonal malaria chemoprevention has substantially reduced malaria incidence among children under five in Moissala. The currently implemented strategy of five rounds of SMC starting in June was estimated to achieve the greatest reduction in cases over the study period. Climate-informed modelling and open-source software can support timely decision-making across settings under changing climate and transmission conditions.
Ochieng', E. A.; Muita, J. W.; Olewe, T.
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BackgroundMalaria 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. ObjectiveThis study aimed to determine factors associated with malaria vaccine hesitancy among caregivers of children 6-59 months in Ugenya Subcounty, Siaya County. MethodologyA 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 ResultsOverall, 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 RecommendationsMalaria 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.
Amankwaah, L.; Boaitey, G. A.; Acheampong, G. A.
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IntroductionAnaemia is one of the most prevalent global public health challenges, particularly among women of reproductive age and children. According to the World Health Organization, anaemia is defined as a hemoglobin concentration below 13.0 g/dL in adult men, 12.0 g/dL in non-pregnant women, and 11.0 g/dL in pregnant women. Hemoglobin measurement therefore plays a critical role in diagnosis, classification, and monitoring of anaemia at both clinical and public health levels. Hemoglobin estimation allows early identification and intervention in at-risk populations. MethodologyA cross-sectional study was conducted at Aniniwaa Medical Centre, Kumasi, involving 100 participants who visited the laboratory for a complete blood count. Venous blood samples were collected aseptically into EDTA tubes and analysed first with the fully automated analyser, followed by the two Hb meters. Data were analysed using Chi-square tests, Bland-Altman plots, and descriptive statistics. ResultsResults showed that the prevalence of anaemia varied across methods: 28% by the analyser, 60% by Urit, and 64% by Mission. Both meters demonstrated 100% sensitivity but lower specificities (55.6% for Urit and 50.0% for Mission). Bland-Altman analysis indicated negative biases (Urit = -1.665 g/dL; Mission = -1.55 g/dL), suggesting both underestimated hemoglobin values compared to the reference. ConclusionThe study revealed that while Hb meters offer convenience and portability for field screening, the fully automated analyser remains more accurate and reliable for diagnosing anaemia in clinical settings.
Carlin, A.; Fantaguzzi, C.; Seife, F.; Leta, G. T.; Phiri, I.; Dhanani, N.; Midzi, N.; Fleming, F. M.
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BackgroundSchistosomiasis remains a major public health challenge in sub-Saharan Africa. Recent World Health Organization (WHO) guidance calls for community-wide treatment and fine-scale data to optimise preventive chemotherapy (PC) strategies, yet the practical implications for resource allocation by health ministries are unclear. MethodsWe analysed epidemiological and cost data from Ethiopia and Zimbabwe to compare survey designs and five implementation scenarios. Scenarios varied by data source, administrative unit of implementation, WHO guidance on PC strategies. Outcomes were target population, praziquantel needs, and delivery costs. ResultsGeostatistical surveys reduced sample size by up to 90% and survey costs by [≥]72% compared with a design-based approach, while increasing spatial coverage. Applying updated WHO guidance expanded eligibility to pre-school-aged children and adults, and in one scenario increased treatment needs by 72% in Ethiopia and 262% in Zimbabwe. Correspondingly, praziquantel requirements and delivery costs were driven primarily by expanded age eligibility rather than geographic coverage. ConclusionsGeostatistical surveys provide substantial efficiency gains for impact assessments, enabling cost-efficient, granular targeting. However, implementing 2022 WHO guidance was the dominant driver of increases in programme scope and resource needs, underscoring the importance of accurate fine-scale data to guide efficient planning and budgeting toward elimination goals. Author summarySchistosomiasis control programmes are required to use finer-scale data and updated World Health Organization (WHO) guidance to decide where and how often to deliver praziquantel. We analysed national schistosomiasis data and programme costs from Ethiopia and Zimbabwe to compare different approaches to impact assessment surveys and to estimate how treatment needs change under alternative decision rules.We found that model-based geostatistical surveys can reduce the number of people that need to be sampled and the cost of surveys while providing more detailed information for planning at sub-district level. However, when we applied the 2022 WHO schistosomiasis guidance, expanded eligibility (including adults and pre-school-age children and a lower threshold for community-wide treatment) substantially increased the number of people needing treatment. In our scenarios, expanded eligibility drove much larger increases in praziquantel requirements and delivery costs than changes in geographic coverage. Our findings help health ministries to anticipate the operational and budget implications of updated guidance and highlight why accurate fine-scale data are essential for equitable and realistic planning toward elimination.