Schistosomiasis remains a public health concern in sub-Saharan Africa, affecting over 250 million people. In endemic settings, schistosomiasis transmission is not always understood exclusively in biomedical terms. Community health workers (CHWs) contribute to schistosomiasis control through mass drug administration and health education, yet limited evidence exists on how they understand schistosomiasis transmission. This study explores how CHWs in Côte d'Ivoire, Kenya and Uganda explain schistosomiasis transmission and how these explanations relate to wider disease and training contexts. This paper draws on the CHW component of a larger mixed-methods study conducted in Côte d'Ivoire, Kenya and Uganda, with multiple respondent groups. We present findings from interviews and focus group discussions with CHWs. Data were analysed thematically, at both semantic (descriptive) and latent (interpretive) level, employing Kleinman's framework of explanatory models and Good's work on semantic networks to support interpretation. CHWs expressed multiple understandings of schistosomiasis transmission. Most described schistosomiasis transmission in biomedical terms, often emphasising skin contact with contaminated water. Others combined biomedical terms with locally circulating ideas about disease transmission, linking infection to drinking unsafe water, stepping on faeces, flies or other diseases such as trachoma or diarrhoeal illnesses. These understandings emerged in relation to a complex disease landscape in which signs, symptoms and perceived transmission routes overlapped. They were also situated within uneven training experiences, including irregular refresher sessions, variable access to schistosomiasis-specific training and training focused mainly on treatment campaign logistics. CHWs' varying understandings of schistosomiasis reflect not only individual knowledge but also the broader disease landscape and training contexts in which they work. Strengthening schistosomiasis communication therefore requires attention to how CHWs interpret, adapt and combine disease-specific information with other sources of knowledge, and to how training can better prepare them to navigate similarities and differences between disease-specific messages in everyday practice.

Intestinal schistosomiasis, caused by infection with Schistosoma japonicum, remains a zoonotic neglected tropical disease (NTD) of significant public health importance in parts of China, the Philippines, and Indonesia. Ongoing schistosomiasis control programmes in these areas have achieved significant reductions in disease prevalence, transmission, and morbidity associated with infection; however, they have also presented new challenges, particularly in detecting and monitoring low-intensity and low-prevalence S. japonicum infections. Highly sensitive and highly specific diagnostic assays are therefore needed for effective disease diagnosis and transmission monitoring in low-endemicity areas, and the development of such assays has been recommended by the World Health Organisation. We first aimed to determine whether a Schistosoma spp. genus-specific real-time PCR assay routinely used to diagnose infections with African schistosome species (namely Schistosoma mansoni and Schistosoma haematobium), as well as two more recently developed S. japonicum species-specific real-time PCR assays, can accurately diagnose low-intensity S. japonicum infections. We also sought to optimise one of the S. japonicum species-specific real-time PCR assays by adding the same DNA extraction and PCR internal positive control target commonly used with the Schistosoma spp. genus-specific real-time PCR assay. This was done using in silico analyses and endpoint PCR with Sanger sequencing and real-time PCR using genomic DNA isolated from Schistosoma spp. adult worms, H2O spiked with individual S. japonicum ova, and naïve human faecal material also spiked with individual S. japonicum ova. We demonstrate that the Schistosoma spp. genus-specific real-time PCR assay and one of the S. japonicum species-specific real-time PCR assays described here are likely incapable of reliably diagnosing low-intensity S. japonicum infections. We also demonstrate that the other S. japonicum species-specific real-time PCR assay can be performed using an additional DNA extraction and PCR internal positive control target and may reliably diagnose low-intensity S. japonicum infections. Whilst clinical assessment of the optimised S. japonicum species-specific real-time PCR assay described here is needed, it is our hope that this assay will become a standard and routinely used method to diagnose low-intensity S. japonicum infections and will be used support future S. japonicum transmission surveillance and elimination programmes.

Introduction Control efforts against schistosomiasis are hampered by the subjective interpretation of the point-of-care circulating cathodic antigen (POC-CCA) urine test, which limits diagnostic consistency. We developed MEDSCAN (Mobile-Enabled Diagnostics for Schistosomiasis Control Analytics), a mobile application that uses smartphone imaging and computer vision to automate POC-CCA interpretation. Methods In a multi-site laboratory evaluation across the USA, the Netherlands, and Kenya, we compared MEDSCAN to visual G-Score interpretation and a benchtop lateral flow reader (LFR). Results All three methods produced clear concentration–response relationships, with normalized machine-based metrics achieving AUROC ≥ 0.90. MEDSCAN demonstrated excellent inter-user reproducibility (intra-class correlation coefficients exceeding 0.94) and substantial agreement with both visual and LFR interpretations across sites. Some device-to-device variability was observed, attributable to differences in smartphone camera hardware and image processing; however, binary diagnostic outcomes remained robust across a heterogeneous set of smartphones. Discussion These results establish operational positivity thresholds for MEDSCAN—based on test-line signal alone or normalized metrics—suitable for direct implementation in field surveillance workflows. A large-scale field study is underway to evaluate MEDSCAN under routine POC-CCA surveillance conditions in endemic settings.

Schistosomiasis control relies on the continued effectiveness of praziquantel (PZQ), yet individual and spatial heterogeneity in PZQ efficacy in the context of repeated mass drug administration (MDA) remains poorly understood. This study aimed to identify individual and spatial determinants of PZQ efficacy against Schistosoma mansoni in rural Uganda. We studied 3870 participants aged 5-90 years from 52 villages in Pakwach, Buliisa, and Mayuge districts in Uganda. Participants were recruited to the SchistoTrack cohort in January-February of 2022 and 2023. Participants received PZQ and were followed up four to five weeks later to assess cure using Kato-Katz (KK) microscopy and point-of-care circulating cathodic antigen (POC-CCA) tests. Logistic regression models were used to identify predictors of cure, defined as a 100% egg reduction rate (ERR). We explored a comprehensive set of 18 sociodemographic, biomedical, water, sanitation, and hygiene, and spatial factors. Subgroup analyses were conducted for adults (aged 18-90) versus children (aged 5-17). Spatial autocorrelation in the outcome and model residuals was assessed using join count statistics and Moran's I. Of 3870 clinical participants, 3704 (95.7%) received PZQ, and 3395 of these had complete clinical data. Among the 3395 treated participants, 1406 (41.4%) were infected with S. mansoni at baseline. The overall cure rate (ERR of 100%) was 76.3%, ranging from 68.9% to 85.4% across districts. Higher odds of cure were associated with older age (OR 1.34) and lower baseline infection intensity (moderate/heavy vs light OR 0.39-0.61). Greater height was associated with lower odds of cure (OR 0.99), which was driven by adults. Compared with Mayuge district, participants in Western districts had lower odds of cure (OR 0.48-0.53). In children, greater distance to water sites with snail presence was linked to higher odds of cure (OR 1.05 per 100m). Results were similar when using POC-CCA outcomes. Spatial clustering of treatment outcomes was observed by district, but no residual spatial autocorrelation remained after accounting for district effects. Incorporating spatial analyses, refining dose assessment, and strengthening post-MDA monitoring may help maintain PZQ effectiveness and support sustainable schistosomiasis control efforts.

Day-to-day variation of Schistosoma haematobium infection and intensity estimates in the near-elimination setting Pemba, Tanzania.

Human schistosomiasis is a parasitic disease of major public health importance in sub-Saharan Africa. Mass drug administration (MDA) with praziquantel (PZQ) is the cornerstone of schistosomiasis control. However, its effectiveness is challenged by variable cure rates and rapid reinfection. Longitudinal data on reinfection and true incidence, which are critical for refining control strategies, are scarce from high-transmission foci like the Lango sub-region in Northern Uganda. This study assessed the efficacy of PZQ and the 24-week dynamics of reinfection and incidence of Schistosoma mansoni among school-aged children in this endemic area. A 24-week prospective cohort study was conducted among 802 primary school children (aged 5-16 years). At baseline, participants were screened for S. mansoni using the modified Kato-Katz technique and allocated into an infected cohort (n = 279) and an uninfected cohort (n = 523). The infected cohort received a single 40mg/kg PZQ dose, with efficacy (cure rate-CR, egg reduction rate-ERR) assessed at 4 weeks. Treatment failures received a second dose. To measure true incidence, the uninfected cohort was re-screened at 4 weeks to identify and exclude prepatent infections at baseline. Reinfection in cured children and incidence in consistently negative children were assessed at 24 weeks. The baseline prevalence was 34.8% (95% CI: 31.5-38.3). After the first PZQ dose, the cure rate was 82.1% (95% CI: 77.0-86.4), and the egg reduction rate was 32.9%. A second dose administered to non-responders achieved a 93.9% cure rate (95% CI: 83.6-97.9). At 24 weeks, the reinfection rate among cured children was 7.7% (95% CI: 4.9-11.8). After excluding prepatent infections (5.9%, 95% CI: 4.1-8.3) detected at 4 weeks, the true incidence of new infections was 5.0% (95% CI: 3.3-7.4) over the 24-week period. Praziquantel remains highly effective for treating S. mansoni in northern Uganda, and a second dose is valuable for curing initial treatment failures. However, the considerable burden of infection at baseline, coupled with notable reinfection and incidence rates within six months, signals persistent high transmission. Operationally, annual MDA may be insufficient; we advocate for piloting more frequent treatment (e.g., biannual MDA), integrating test-and-re-treat strategies (with careful cost-effectiveness evaluation), and strengthening complementary WASH and snail control interventions.

Schistosomiasis control has transitioned from focusing on morbidity control to elimination of the disease. Nevertheless, preschool-age children (PSAC) are left out of control programs and consequently serve as a source of continued transmission. This study determined the prevalence and predictors of Schistosoma mansoni infection among PSAC. An analytical cross-sectional study was conducted among 417 PSAC. The infection prevalence and intensity was determined using the Kato-Katz technique and a structured questionnaire was used to collect demographic and risk profile. A logistic regression model was used to determine factors associated with S. mansoni infection. The prevalence of S. mansoni infection was 14.4% (95% confidence interval [CI] 11.2 to 18.1) and the geometric mean eggs per gram of faeces was 77.2 (95% CI 61.7 to 96.6) with 33.3% and 5.0% having moderate and heavy infections, respectively. Passive water contact (adjusted odds ratio [AOR] 7.19 [95% CI 2.34 to 21.81]) and living within 500m of a water body (AOR 16.25 [95% CI 4.97 to 53.21]) were significantly associated with S. mansoni infection (p<0.001). PSAC are at risk for S. mansoni infection and accumulating moderate to heavy infections. Proximity to a water body and engaging in passive water contact activities were significant predictors of infection. These findings call for the inclusion of PSAC in the ongoing praziquantel mass drug administration programs. There is an urgent need for improved water supply, sanitation and public health education to reduce population exposure to infested freshwater bodies.

Schistosomiasis remains the second leading cause of death among parasitic diseases globally, contributing substantially to chronic morbidity and disability. South Africa (SA) is endemic for schistosomiasis, with ongoing efforts to expand mass drug administration. In the absence of true prevalence data, this study retrospectively analysed public sector laboratory-confirmed schistosomiasis cases from 2019 to 2024. Over this period, 73,680 cases were microscopically diagnosed, with Schistosoma haematobium accounting for 99.9% of infections. The test positivity rate of 20 per 100,000 population is lower than previously reported, with the burden concentrated among boys aged 5-19 years, particularly in the KwaZulu-Natal, Limpopo, and Mpumalanga provinces. These findings highlight a persistent burden within defined demographic groups and geographic areas, while also suggesting possible early signs of improvement that are potentially linked to public health interventions. The results provide valuable evidence to inform the scale-up of national schistosomiasis control programmes and the prioritisation of interventions towards the most affected populations.

Schistosomiasis remains a critical global health issue, necessitating novel therapies due to emerging praziquantel resistance. We previously developed a patented praziquantel derivative, DW-3-15, which demonstrated potent broad-spectrum schistosomicidal activity through SjHAT1 inhibition. Here, the full-length SjHAT1 cDNA is cloned by rapid amplification of cDNA ends methods. The protein encoded by the cDNA retains conserved catalytic residues of acetyltransferases although sharing 34% identity with mammalian orthologs. Enzyme activity analysis reveals that recombinant SjHAT1 exhibits 130 μU/mL histone acetyltransferase activity at 25°C for 60 min, and is completely inhibited by DW-3-15 at a concentration of 50 μM. However, DW-3-15 has no effect on the enzymatic activity of the human ortholog HAT1. Phylogenetic analyses place SjHAT1 in a distinct clade, and molecular docking results indicate significant divergence compared to its human ortholog HsHAT1. The expression profiling of SjHAT1 reveals stage- and sex-specific patterns. Fluorescence in situ hybridization localizes SjHAT1 predominantly in female vitellaria and male parenchyma near the gynecophoral canal. Knockdown of SjHAT1 reduces worm survival by 57.5% in vivo, suppresses female oviposition by 90.8% in vitro and 79.2% in vivo, and disrupts ovarian and vitelline architecture. RNA-sequencing analysis reveals that SjHAT1 knockdown disrupts β-alanyl-tryptamine (BATT) pheromone signaling via downregulation of aromatic L-amino acid decarboxylase (AADC) in males and multidrug resistance-associated protein 4 (MRP4) in females. Given that BATT is essential for inducing female sexual development and egg production, the observed transcriptional dysregulation provides mechanistic evidence for disrupted intersexual communication. Our findings identify that SjHAT1 is a central regulator of schistosome reproductive biology. These sex-specific mechanisms highlight SjHAT1 as a potential therapeutic target for treatment and control of schistosomiasis.

Urinary schistosomiasis is a neglected tropical disease that remains endemic in much of sub-Saharan Africa, with Nigeria bearing a considerable burden. Despite ongoing mass drug administration, infection continues to affect school-aged children in endemic communities. This study assessed the prevalence of urinary schistosomiasis among school-aged children in parts of Anambra State, Nigeria, and examined demographic, environmental, and water-use behaviours associated with infection. A cross-sectional study was conducted between August and November 2025 in rural, semi-urban, and urban communities selected for freshwater use in domestic, agricultural, and recreational activities. Urine samples from 388 children aged 5-14 years were analysed using dipstick and filtration methods, and structured questionnaires were used to assess knowledge, attitudes, and practices. The overall prevalence was 13.1%, with higher rates in rural communities. The infections were mostly light to moderate, with a few heavy cases, and haematuria was uncommon. Knowledge of schistosomiasis was generally poor; however, participants reported relatively positive attitudes and acceptable hygienic practices. Multivariate analysis identified haematuria and mean attitude score as associated factor of infection, with higher attitude scores associated with lower odds of infection. However, this result should be interpreted with caution due to the low internal consistency of the attitude scale. The higher burden in rural communities highlights existing health inequities and the need for geographically targeted, equity-focused control strategies. This underscores the importance of multisectoral collaboration for sustainable control of schistosomiasis, in line with global neglected tropical disease elimination targets and the Sustainable Development Goals. The findings highlight persistent transmission driven by behavioural and environmental factors and support the need for combined control strategies that integrate behavioural interventions, improved diagnostics, and environmental management.

Schistosomiasis, a parasitic disease transmitted by freshwater snails, affects over 251.4 million people globally, with sub-Saharan Africa bearing 95% of the disease burden. This study evaluates the phytochemical composition, characterizes the bioactive secondary metabolites, antioxidant, anti-inflammatory, and the cercaricidal properties, as well as the biosafety of the methanolic and hexane extracts of Chromolaena odorata. Phytochemical screening of C. odorata extracts identified tannins, flavonoids, and saponins in the methanolic extract and steroids and alkaloids in the hexane extract. LC-MS and HPLC-UVESI-TOF-MS analyses confirmed the presence of polyphenols (flavonoids) and aromatic dicarboxylic acid compounds. Antioxidant analysis revealed strong free radical scavenging potential of the plant extracts. Both extracts demonstrated potent cercaricidal activity against Schistosoma mansoni, with LC50 values as low as 0.2012 and 0.2410 μg/mL, respectively. The anti-inflammatory effects were determined via inhibition of heat-induced albumin denaturation, with plant extracts able to inhibit protein denaturation, particularly the methanolic extract that shows a percentage of inhibition of 73.56% at the highest concentration tested. Cytotoxicity assays on LLCMK2 cells showed low toxicity of the extracts. These findings suggest that crude C. odorata extracts possess antischistosomal, antioxidant, and anti-inflammatory properties, supporting their potential integration into primary healthcare strategies for schistosomiasis control.

Sensitive diagnostic tools are essential to support schistosomiasis control and elimination programs, yet most long-standing parasitological and serological tests lack sufficient accuracy in low-intensity settings. The Helmintex (HTX) method, based on magnetic isolation of Schistosoma mansoni eggs from large stool volumes, is highly sensitive and serves as a reference standard for evaluating other diagnostic approaches but remains labour-intensive. We evaluated modifications aimed at reducing workload while preserving or enhancing performance. Eggs were seeded into human faeces and processed using standard HTX versus three key modifications: (i) cellulase digestion in 20% Tween-20, (ii) density separation with 60% Percoll and (iii) replacement of BioMag beads with magnetite nanopowder. In addition, we standardised an auramine-O fluorescent staining protocol for batch processing of HTX sediments from naturally infected samples. Sequential cellulase and Percoll treatments reduced the final sediment volume by 42.9%. Magnetite at 25 mg/mL achieved an average egg recovery of 70.4% compared with 38.5% for BioMag beads. Auramine-O staining facilitated rapid visualisation of eggs and retained fluorescence for at least 90 days. Together, these refinements streamline the HTX method, reinforcing its utility as a reference standard and positioning it as a practical tool for certification of transmission interruption in schistosomiasis-endemic areas.

BackgroundIn China’s post-transmission-interruption stage of schistosomiasis control, infection signals are often sparse, and conventional surveillance indicators focused on infection detection may not adequately capture residual risk across heterogeneous ecological settings. This study aimed to develop an operational indicator framework for assessing schistosomiasis transmission risk and supporting routine risk assessment and management in this stage.MethodsA county-level indicator framework for schistosomiasis transmission risk assessment was developed through a two-round Delphi consultation and weighted using a combined Delphi-entropy weight method. Using longitudinal data from six pilot counties during 2020–2024, an annual composite risk index (R) was calculated by weighted linear aggregation and classified into risk levels with trapezoidal fuzzy membership functions. Robustness was evaluated by perturbing the subjective preference coefficient (α) and examining the consistency of county-year rankings across scenarios using Spearman’s rank correlation.ResultsThe final framework comprised three first-level, twelve second-level, and thirty-nine third-level indicators spanning biological, environmental, and social domains. Across the six pilot counties, R ranged from 0.18 to 0.44 and the overall risk level was predominantly low. Nonetheless, distinct county-level risk profiles were observed between lake/marshland and mountainous settings. Risk rankings remained highly consistent under α perturbations (ρ = 0.909–0.998), indicating good robustness of the assessment results.ConclusionsThis framework translates multidimensional determinants relevant to the re-establishment of schistosomiasis transmission into interpretable county-level risk profiles. It provides an operational tool to support targeted surveillance and more efficient allocation of control resources in low-endemicity contexts.Supplementary InformationThe online version contains supplementary material available at 10.1186/s40249-026-01453-6.

Mass drug administration campaigns have enabled great progress in the prevention and control of schistosomiasis and soil transmitted helminthiasis. However, the persistence of these infections continues to challenge public health systems despite decades of control efforts. This study was commissioned to evaluate the feasibility of a transition from periodic mass drug administration campaigns to a sustainable, facility- and community-based delivery model in Western Kenya. The study is part of a non-randomized, controlled before-and-after study using a mixed-methods approach. Data were collected from 1,229 households, 24 health facilities (12 control, 12 intervention), focus group discussions, and key informant interviews. The analysis focused on six domains of mainstreaming feasibility: perception of mainstreaming among key stakeholders, processes, infrastructure and system readiness, acceptability and trust for primary healthcare-led treatment, facilitators, and barriers. Finally, we calculated a composite readiness index to grade facility readiness. Generally, community perceptions to schistosomiasis and soil-transmitted helminthiasis treatment benefits were found to be high in both the control and intervention groups. Qualitative data showed enhanced trust in the integrated model by virtue of the credibility and professional nature of health facility staff. An overwhelming majority of community members received treatment through household visits (95.5%) implying reliance on periodic MDA at baseline. Community Health Promoters remain a critical source of information on treatment opportunities for low-literacy populations, while media and health facilities are increasingly important among more educated groups. We also found high infrastructural and systemic readiness for treatment mainstreaming with respect to stock availability and data reporting systems. However, stock outs were reported among the facilities. High variability in health worker training coverage suggests a critical challenge in workforce preparedness. The findings point to a strong foundation for mainstreaming but underscore the need for a structured implementation package. Priority actions should include standardized operating procedures, supply chain and digital system strengthening, and expanded Community Health Promoter-led outreach activities to improve consistency, access, and sustainability of deworming services within primary healthcare platforms. Registration number NCT07507461, prospectively registered on 28th January, 2026.

BackgroundSchistosomiasis control relies largely on preventive chemotherapy; however, rapid reinfection persists in many endemic settings due to continued transmission by freshwater snail intermediate hosts. Biological control using natural predators has been proposed as a complementary strategy to reduce vector snail populations. The invasive North American crayfish Procambarus clarkii, which preys on schistosome-transmitting snails, represents a promising candidate. However, the ecological and biological factors influencing predator–prey interactions between crayfish and intermediate snail hosts remain poorly understood.MethodsWe evaluated the predatory potential of Procambarus clarkii on schistosomiasis-transmitting snails under controlled laboratory conditions. Aquarium-based experiments assessed the effects of snail species, infection status, prey size, and crayfish developmental stage on predation dynamics. Predation outcomes were quantified using cumulative predation and time-to-depletion analyses and analysed using exact binomial tests, Fisher’s exact tests, generalized linear models (GLMs), and paired Wilcoxon signed-rank tests.ResultsIn early-time cumulative predation analysis, infected snails were consumed more frequently than uninfected snails (64.3% vs. 35.7%; exact binomial test, p = 0.044). Time-to-depletion analysis also showed earlier clearance of infected snails (median 18 h vs. 20 h; paired Wilcoxon signed-rank test, p = 0.002). Predation did not differ significantly between snail species (p = 0.37), indicating no evidence of species-specific prey selection. Crayfish exhibited size-dependent predation, preferentially consuming larger snails (7–12 mm) over smaller snails (< 6 mm; p = 0.04), with no significant differences observed among larger size classes (p = 0.44). In predator–prey stage experiments, adult crayfish consumed similar proportions of adult and juvenile snails (82.8% vs. 80.6%), whereas juvenile crayfish consumed significantly more juvenile than adult snails (63/180 vs. 10/180; p < 0.001).ConclusionPredation by Procambarus clarkii was influenced by prey size and infection status rather than species identity. The preferential removal of infected and larger snails provides experimental evidence for the potential of crayfish as a complementary biological control agent within integrated schistosomiasis control strategies.

Sex-specific presentation, epidemiology, and control of schistosomiasis in women and adolescent girls.

BackgroundSchistosomiasis remains a major neglected tropical disease in Ghana with substantial health and social consequences for women and girls. Long-standing mass drug administration (MDA) programmes with praziquantel have been implemented since 2008, yet the disease remains endemic in Ghana raising significant concerns about World Health Organization (WHO) efforts towards elimination by 2030. The study thus aimed to assess the spatio-temporal and hotspots for female schistosomiasis (FS) in Ghana and provide insight that informs gender-sensitive public health interventions.MethodsWe conducted an ecological, retrospective, spatio-temporal analysis using routine surveillance data on FS. Case counts from female population data were extracted from the District Health Information Management System 2 (DHIMS-2) for all 260 districts in Ghana between 2020 and 2024. Annual and period prevalence per 10,000 female populations were estimated. Global Moran’s I was used to assess spatial autocorrelation, and clustering and hotspots were assessed using Anselin Local Moran’s I and Getis-Ord Gi* statistics respectively, with False Discovery Rate (FDR) correction.ResultsA total of 4864 FS cases were reported over the five years, with a significant increase in prevalence from 71.9 cases per 10,000 female population in 2020 to 99 cases per 10,000 female population in 2024. Majority of the cases occurred in the second half of the year. There was an observed diffusion of prevalence of the cases from the east-southern to west-southern part of the country. Spatial autocorrelation was observed for FS (Moran I index = 0.060032, Z-Score = 2.650757 and a P < 0.008). Ten districts showed high-high clustering, with districts in middle and south-western zones of the country showing significant hotspots for female schistosomiasis in Ghana.ConclusionsThe occurrence of female schistosomiasis is not a coincidence. Female populations in approximately 6.5% hotspot districts are at significant risk of female schistosomiasis infection. Hence, gender sensitive schistosomiasis control, including targeted MDA, should be directed towards clustered hotspots, focusing on zones with low prevalence fenced off by high prevalence zones.Graphical

Effective diagnosis of Schistosoma haematobium is critical for disease management. However, current tools often lack sensitivity for low-intensity infections, a challenge noted in the recent WHO Roadmap for Neglected Tropical Diseases. This study aimed to evaluate a novel cell-free DNA (cfDNA) quantitative Polymerase Chain Reaction (qPCR) assay, utilizing 20µl of plasma with crude DNA extraction. This approach intends to improve diagnostic accuracy and lower implementation barriers for molecular tests in field settings. We compared its performance against urine filtration microscopy and the Up-converting Reporter Particle Lateral Flow Circulating Anodic Antigen (UCP-LF CAA) test in pregnant women from Lambaréné, Gabon. A prospective cross-sectional study was conducted on 296 pregnant women in Gabon. EDTA blood, urine, and stool samples were collected from December 2018 to November 2020. Urine samples were analyzed by urine filtration microscopy and UCP-LF CAA. The cfDNA qPCR assay was performed retrospectively on 20µl of frozen plasma using a simplified DNA extraction method. Diagnostic accuracy was assessed via sensitivity, specificity, and agreement measures. Bayesian latent class analysis (BLCA) was used to estimate test performance in the absence of a gold standard. Diagnostic positivity varied: 24.3% by cfDNA qPCR, 18.6% by urine filtration microscopy, and 20.9% by UCP-LF CAA. Agreement between tests was limited. BLCA indicated qPCR to be the most sensitive (74.0%, 95% CrI:57.2-90.8), followed by UCP-LF CAA (65.7%, 95% CrI:49.0-82.8). Microscopy was the most specific (94.9%, 95% CrI :89.6-99.3). Estimated prevalence ranged between 22.5 and 27.1%. Receiver operating characteristic (ROC) analysis confirmed good individual performance (AUC 0.837-0.868), with performance improving when combining any two tests (AUC up to 0.931). This study validates the high sensitivity of a novel cfDNA qPCR approach using only 20µl of plasma, demonstrating performance comparable to microscopy and UCP-LF CAA. While microscopy maintains high specificity, combining it with a high-sensitivity test such as qPCR or UCP-LF CAA provides significant diagnostic improvement. Further optimizing the specificity of this streamlined qPCR assay brings us closer to a highly accurate, feasible point-of-care diagnostic crucial for schistosomiasis control programs in resource-limited settings.

Background/Objectives: Intestinal schistosomiasis caused by Schistosoma mansoni is often underestimated in low-transmission settings due to the limited sensitivity of traditional stool microscopy. More sensitive approaches, including antigen detection and molecular diagnostics, are required to detect infections where egg excretion is low or intermittent. This study aimed to determine the prevalence of S. mansoni infection among school-going children in Nelson Mandela Bay (NMB) using a multi-modal diagnostic approach. Methods: This cross-sectional study included 759 schoolchildren aged 5–14 years from 15 primary schools in NMB. Stool samples were analyzed using the Kato–Katz technique to detect S. mansoni eggs, while urine samples were tested using the point-of-care circulating cathodic antigen (POC-CCA) assay for antigen detection. A subset of stool samples from POC-CCA-positive participants (n = 28) was further analyzed using conventional PCR (cPCR), targeting the S. mansoni cox1 gene, for molecular confirmation. Only a single stool specimen was collected per participant. Results: Among the 759 participants (58% male, 42% female), no egg-positive cases were detected. However, POC-CCA testing identified S. mansoni antigen in 3.2% of participants. Of the 28 POC-CCA-positive samples analyzed by cPCR, 9 (32.1%) were PCR-positive, representing molecular confirmation within the antigen-positive subset rather than overall prevalence. Conclusions: Traditional microscopy underestimated S. mansoni prevalence in this low-prevalence setting. Antigen detection combined with molecular diagnostics improved case identification and highlighted ongoing transmission. These findings support the integration of sensitive diagnostic tools into schistosomiasis surveillance and control strategies in South Africa.

Urogenital schistosomiasis caused by Schistosoma haematobium remains endemic in sub-Saharan Africa. Diagnosis traditionally relies on urine microscopy to detect parasite eggs; however, its sensitivity declines in low-intensity infections. Artificial intelligence (AI)-assisted image analysis offers a promising approach to automate egg detection and enhance diagnostic accuracy, but its performance compared with standard microscopy is not well established. We conducted a systematic review following the PRISMA guidelines and checklist. Studies evaluating AI-assisted detection of S. haematobium compared with microscopy and/or molecular reference standards, published up to August 2025, were identified through searches in PubMed/MEDLINE, HINARI, Epistemonikos, Science Direct, Google Scholar and grey literature sources. Eligible studies were selected based on pre-defined inclusion and exclusion criteria. The quality of included studies was assessed using the QUADAS-2 tool. Heterogeneity among studies was evaluated using the Cochrane Q test and I² statistic. Data was analyzed using STATA version 14.1 and Review Manager version 5.4.1. Ten studies (15 datasets, 5,564 urine samples) conducted in sub-Saharan Africa met the inclusion criteria. AI-assisted tools demonstrated high diagnostic accuracy. The pooled sensitivity was 88% (95%CI 83%-91%) and pooled specificity was 89% (95% CI 83%-93%). The pooled diagnostic odds ratio was 54.00 (95% CI 30.41-95.88), indicating strong discrimination between infected and uninfected cases. The SROC curve yielded an AUC of 0.94 (95% CI 0.92-0.96), reflecting excellent overall accuracy. Heterogeneity across studies was high (I² = 100%), suggesting results varied by the specific AI platform and study context. AI-assisted microscopic diagnosis of S. haematobium achieved very good in this meta-analysis. These automated tools, whether smartphone-based or bench-top systems, showed promise for detecting infections and could help screen populations in endemic areas. With further validation in field settings and comparison to highly sensitive reference tests, AI diagnostic technology may become a valuable tool to improve case detection and support schistosomiasis control and elimination efforts.