Contemporary challenges of Schistosomiasis mansoni in Brazil: a review of epidemiological indicators, SUS protocols, and control strategies (2010–2026)

This scientific review analyzes the contemporary epidemiological landscape and public health management of Schistosomiasis mansoni in Brazil for the 2024–2026 triennium. The main objective of this study is to provide multiple diagnostic and environmental engineering dimensions, extending beyond normative official manuals to analyze systemic surveillance vulnerabilities, detection biases, and the chronic morbidity legacy in an aging population. Despite decades of control initiatives, Brazil remains the primary endemic epicenter in the Americas, currently transitioning from a morbidity control paradigm toward the World Health Organization’s goal of total transmission interruption. This study examines a paradoxical epidemiological transition where declining aggregate national prevalence is counterbalanced by the entrenchment of the disease in high-endemicity “pockets” in the Northeast and Southeast Regions. We evaluate the critical demographic shift toward an aging population presenting with severe chronic “legacy burdens,” such as Symmers’ pipe-stem fibrosis and portal hypertension. Within the scope of the Unified Health System (SUS), this review assesses the strategic shift toward high-sensitivity diagnostics, including point-of-care circulating cathodic antigen (POC-CCA) and molecular assays, to identify asymptomatic carriers. Furthermore, the analysis highlights the necessity of Integrated Environmental Engineering (IEE) and the Brazilian Legal Framework for Sanitation as definitive structural interventions to sustain elimination. We conclude that achieving the 2030 elimination target requires an unwavering “One Health” commitment, integrating rigorous clinical follow-up for chronic patients with universal sanitation and proactive malacological surveillance. Schistosomiasis, popularly known in Brazil as “barriga d’água,” remains a persistent public health threat despite decades of combat efforts. While the country has successfully reduced the number of deaths and severe acute cases, the disease has adapted and has found “pockets” of transmission in urban peripheries and coastal areas, where a lack of sanitation and clean water keeps the parasite in circulation. Our study highlights a concerning shift: the disease is now heavily affecting older people who have carried the infection for years, leading to severe liver and intestinal complications that are difficult to treat in advanced stages. We argue that simply providing medication is not enough to eliminate schistosomiasis. True eradication requires a “One Health” approach—an integrated strategy that combines high-sensitivity diagnostic tests with massive investments in basic sanitation and environmental engineering. By changing the environments where the snail hosts thrive and ensuring that every citizen has access to treated water, Brazil can ultimately break the cycle of poverty and disease, meeting the global goal of eliminating schistosomiasis as a public health problem by 2030.

The global and national imperative for schistosomiasis elimination: a comprehensive strategic analysis

Schistosomiasis, an intravascular parasitic disease caused by trematodes of the genus Schistosoma, represents one of the most significant challenges to contemporary global health and is rightfully categorized as a primary neglected tropical disease (NTD). While official Ministry of Health (MS) technical manuals establish normative operational workflows, this synthesis critically addresses systemic vulnerabilities—including the contraction of active municipal screening (SISPCE), COVID-19 pandemic-induced underreporting, and persistent chronic liver morbidity in aging cohorts—while emerging biotechnological tools such as environmental DNA (eDNA) and vector genomics are integrated to bridge operational gaps toward the WHO 2030 target. Within the current international healthcare architecture, the disease plays a central role in the World Health Organization (WHO) roadmap for 2021–2030 (1, 2). This strategic framework marks a historical pivot from traditional morbidity control, which focused merely on reducing parasite intensity, to the ambitious goal of total transmission interruption. This roadmap mandates the implementation of multifaceted, integrated interventions that synthesize preventive chemotherapy, rigorous snail control, and structural enhancements in water, sanitation, and hygiene (WASH) infrastructure to ensure that the elimination of the disease is not only achieved but also biologically and socially sustained (3). In addition, recent national guidelines from the Brazilian Ministry of Health (4) and experts from FioSchisto (5) emphasize tailored local strategies. To fully encompass the One Health approach, nonhuman definitive hosts, particularly wild rodents (e.g., Nectomys squamipes) and other mammals, must be considered because of their active role in maintaining the parasite’s biological cycle in endemic areas (4, 6).

In the geopolitical context of the Americas, Brazil serves as the paramount endemic epicenter, historically functioning as the primary reservoir for the pathogen in the Western Hemisphere. Epidemiological surveys from the mid-1990s documented a staggering burden, with prevalence estimates exceeding six million infected individuals. While decades of public health initiatives have successfully mitigated the most lethal acute clinical manifestations, the persistence of high-endemicity clusters reinforces the need for a coordinated national response. Robust public health surveillance is essential to prevent the resurgence of parasites in areas where transmission dynamics remain volatile (7, 8).

Study design, database search strategy, and secondary data extraction

This study employs a narrative synthesis review design complemented by secondary epidemiological data analysis. A comprehensive literature search was conducted across the PubMed/MEDLINE, SciELO, ScienceDirect, and official Brazilian Ministry of Health repositories for records published between January 2010 and February 2026. Search strings combined key terms: (“ Schistosoma mansoni ” OR “Schistosomiais”) AND (“Brazil” OR “SUS”) AND (“Epidemiology” OR “Diagnosis” OR “Praziquantel” OR “One Health” OR “Sanitation”). The inclusion criteria included peer-reviewed original research, systematic reviews, official technical guidelines (MS/WHO), and official public health data series. Non-peer-reviewed commentaries, duplicate reports, and studies lacking epidemiological relevance to Brazil were excluded.

Operational differentiation between the SINAN and SISPCE databases

Secondary epidemiological metrics specifically distinguish clinical cases reported in the Notifiable Diseases Information System (SINAN) from screening positivity rates in the Schistosomiasis Control Program Information System (SISPCE):

SINAN (Sistema de Informação de Agravos de Notificação): A nationwide mandatory system tracking the passive and active notification of individual confirmed clinical cases, sociodemographic variables (sex, age, race, location), clinical forms, and aggregate national incidence trends across all healthcare levels.

SISPCE (Sistema de Informação do Programa de Controle da Esquistossomose): An active surveillance database operated specifically by municipal endemia control teams in recognized endemic zones, tracking routine active parasitology surveys (fecal Kato-Katz exams), municipal population screening coverage, and local positivity rates.

Biological determinants and molecular invasion dynamics

The sustained transmission of Schistosoma mansoni within the Brazilian ecosystem is linked to the biological and physiological efficiency of its intermediate hosts, particularly the freshwater gastropod Biomphalaria glabrata. This mollusk species is recognized as the most effective vector because of its high degree of compatibility with the parasite, allowing for massive asexual replication within its tissues and the subsequent shedding of thousands of infective larvae (9, 10).

The transition from the aquatic environment to the definitive human host is facilitated by cercariae, the highly specialized larval stage. These larvae are equipped with a sophisticated molecular toolkit designed for rapid percutaneous invasion. Upon contact with human skin, cercariae release a potent cocktail of elastases and proteases that enzymatically dissolve the dermal extracellular matrix. Simultaneously, they deploy an array of molecular immunomodulators that suppress the host’s innate immune response, effectively “cloaking” the parasite during the critical initial phases of infection and ensuring successful migration into the venous system (11, 12).

Epidemiological dynamics and spatial heterogeneity of schistosomiasis in Brazil

The current epidemiological profile of schistosomiasis in Brazil, as evidenced by longitudinal data spanning from 2010 to 2023, reveals a complex and paradoxical transition in disease dynamics. According to the reported case series (Figure 1), the absolute number of notifications and the corresponding incidence rates exhibited a period of relative stability between 2010 and 2015, followed by a significant epidemic surge that peaked between 2016 and 2018. After this peak, a sharp decline in reported cases is observed from 2019 onward, reaching its nadir during the 2020–2022 period. This marked reduction must be interpreted with extreme caution, as it strongly reflects detection bias, severe underreporting, and the operational disruption of active field surveillance during the COVID-19 pandemic, alongside a sharp decrease in municipal participation in active SISPCE screening, rather than a total biological interruption of transmission (4, 5, 13). The aggregate national notification rate of 19.83 per 100,000 inhabitants reported for 2023 was calculated using total confirmed cases registered in SINAN (N = 40,314) as the numerator, divided by the total IBGE estimated resident population of Brazil for 2023 (N ≈ 203,080,756) as the denominator, multiplied by 100,000 (14). SISPEC data were not used for this aggregate national rate, as the SISPCE reflects positivity strictly within actively surveyed endemic municipalities. Geographically (Figure 2), the Northeast region, specifically the states of Pernambuco and Alagoas, and Southeast Brazil remain primary epicenters. In accordance with the official Ministry of Health technical guidelines (MS, 2024), endemicity is operationally stratified by survey positivity rates into low (<5%), moderate (5–14.9%), and high (≥15%) endemicity (4, 15). Persistent “pockets of high endemicity” refer to localized microgeographic clusters (e.g., peri-urban settlements or coastal communities) that maintain active screening positivity rates ≥ 15% because of persistent Biomphalaria infestation and inadequate sanitary infrastructure (15–17). In regions such as coastal Pernambuco, the prevalence rates in rural and peri-urban areas can reach 80%, a phenomenon driven by the synergy of historical socioenvironmental vulnerability and the expansion of the parasite into zones previously classified as low risk (18, 19). Consequently, the decline in the aggregate volume of notifications must be interpreted with caution, as it may reflect both the success of localized interventions and potential underreporting or shifts in diagnostic focus during the transition toward the 2024–2026 period.

The demographic transition of the disease is evident upon analysis of the current data (Figure 3), which shows a predominant concentration in adults and older individuals (mean age 40, median age 39). This pattern does not solely reflect a primary “demographic transition of transmission” but is substantially confounded by general population aging in Brazil and shifts in diagnostic screening. As routine active school-based screening declined, detection shifted toward passive presentation in primary health units (UBS), capturing an aging cohort carrying a cumulative “legacy burden”–individuals infected decades ago who developed progressive liver fibrosis (Symmers’ fibrosis) due to unmanaged chronic exposure (13). This is corroborated by the age distribution pyramid, which shows a predominant concentration of cases in the 30 to 39 and 40 to 49 age brackets, as well as a significant volume in individuals over 60 years of age. Recent clinical data from 2024 highlight this critical shift, necessitating specific diagnostic strategies for chronic forms and hepatic complications. Notification records indicate that approximately 58.06% of cases are male, a group that consistently shows higher infection volumes across nearly all adult age groups. With respect to sociodemographic indicators, the “brown” (mixed-race) population remains the most affected, accounting for 48.27% of the total notifications, with a notable longitudinal increase reaching 62% by 2023. Furthermore, the disease is strongly prevalent, with 78.35% of cases residing in urban zones and 15.97% in rural areas. Rather than indicating a primary shift in vector transmission alone, this concentration in urban areas is largely driven by migration to urban agglomerations, compounded by structural health system deficiencies in rural areas. SISPECE data from 2009 onward demonstrate that many rural municipalities abandoned routine control program (PCE) activities, resulting in a drastic reduction in diagnostic fecal examinations (16, 17). This shift suggests that the healthcare system is increasingly managing a burden of chronic infections where long-term exposure has culminated in severe pathologies such as Symmers’ pipe-stem fibrosis and portal hypertension (13, 17–20). The synergy of high urbanization and an aging infected population necessitates a recalibration of public health interventions to address these entrenched pockets of morbidity.

Molecularly, fibrosis in Symmers is a systematized periportal process driven by a dysregulated T-helper 2 (Th2) immune response to trapped parasite eggs. These eggs secrete antigens that trigger the release of profibrotic cytokines, such as interleukin-13 (IL-13) and transforming growth factor-beta 1 (TGF-β1), which activate hepatic stellate cells to deposit excessive amounts of collagen in the portal tract. This leads to intrahepatic portal flow obstruction, esophageal varices, and a stabilization of residual mortality rates in regions where diagnostic delays prevent early intervention (3, 12).

Strategic transition and economic engineering within the SUS

In response to these challenges, the clinical and epidemiological protocols of the Brazilian Ministry of Health have overhauled the transition of the Unified Health System (SUS) into an active elimination phase. This strategy moves beyond simple morbidity management toward a multidimensional framework that addresses the root causes of transmission. A primary focus is the shift from traditional, low-sensitivity Kato-Katz (K-K) fecal smears to high-sensitivity diagnostic technologies. The implementation of the point-of-care circulating cathodic antigen (POC-CCA) urine test allows for the detection of low-parasite-load infections and asymptomatic “supreaders” who would otherwise remain untreated and continue to fuel the transmission cycle (9, 20).

Furthermore, the 2024–2026 strategic plan emphasizes Integrated Environmental Engineering (IEE) as a superior long-term investment compared with exclusive reliance on the Mass Drug Administration (MDA). While MDA with praziquantel remains essential for reducing immediate morbidity, IEE initiatives, such as the paving of open drainage ditches, the installation of “snail-proof” irrigation, and the provision of universal treated water, permanently modify the habitat of Biomphalaria snails. Although the initial capital investment for IEE is higher, its long-term cost-effectiveness is superior in elimination settings, as it prevents reinfection and reduces the long-term economic burden associated with chronic disability and lost productivity (8, 21).

This convergence of molecular insights, sensitive diagnostic surveillance, and structural environmental reform represents the current Brazilian paradigm for eradicating schistosomiasis. By integrating longitudinal care for the aging chronic population with aggressive localized interventions in peri-urban “pockets,” the SUS aims to break the cycle of infection and achieve the WHO elimination goals by 2030 (3, 22).

Clinical and diagnostic framework of schistosomiasis within the unified health system

When performed by well-trained technicians, the specificity of the Kato–Katz (K-K) method is 100%. Within the routine flow of the Unified Health System (SUS), Kato-Katz remains the primary formally incorporated parasitological method for routine screening in primary health units (UBS) (4). Conversely, advanced or experimental diagnostic tools must be clearly distinguished by their SUS incorporation status (4, 5, 23):

POC-CCA Rapid Urine Test: Despite its field utility, POC-CCA is not recommended or formally incorporated by the Brazilian Ministry of Health for routine SUS because of unsatisfactory specificity and false-positive results observed in nonendemic Brazilian settings (4, 23).

Molecular Assays (qPCR/eDNA) and ultrasensitive CAAs: Highly sensitive tools restricted to the research setting and national reference laboratories (e.g., Fiocruz) for evaluating persistent cases or low-density foci (4, 5).

Helmintex and Serology (ELISA): Specialized parasitological and serological assays are utilized primarily in reference centers for posttreatment verification and transmission elimination monitoring (4, 5).

The clinical management of schistosomiasis within the Brazilian Unified Health System (SUS) is predicated on a nuanced understanding of the disease’s progression, which is bifurcated into distinct acute and chronic phases. The initial acute phase is characterized by cercarial dermatitis, a localized hypersensitivity reaction at the site of larval penetration and Katayama fever. The latter represents a systemic immune complex-mediated syndrome manifesting as fever, malaise, myalgia, and eosinophilia. Despite its clinical significance, Katayama fever is frequently underreported in national databases because of its nonspecific presentation, which often leads to misdiagnosis as other prevalent tropical febrile illnesses. As the infection transitions into the chronic phase, clinical manifestations diversify into intestinal, hepatointestinal, and severe hepatosplenic forms. The hepatosplenic stage is particularly critical, as it involves the development of periportal fibrosis, portal hypertension, and splenomegaly and requires a sophisticated transition from primary health care to specialized tertiary centers, as shown in Figure 4 (20, 24).

When performed by well-trained technicians, the specificity of the Kato-Katz (K-K) method is 100%, as the detection of schistosome eggs directly confirms infection (4). However, its sensitivity is profoundly compromised in low-endemicity settings. To mitigate this limitation, current Brazilian guidelines mandate the examination of multiple slides from different fecal samples (4). Furthermore, upcoming diagnostic advances, such as automated reading of K-K slides, offer promising potential to standardize and streamline high-throughput parasitological screening. A critical assessment of the current POC-CCA is essential: despite its field utility, POC-CCA is not currently recommended or approved by the Brazilian Ministry of Health (4). Thorough field evaluations in Brazil have demonstrated unsatisfactory performance, including false-positive results in nonendemic and uninfected individuals (23). Furthermore, polymerase chain reaction (PCR) diagnostics and ultrasensitive assays targeting circulating anodic antigen (CAA) have demonstrated superior diagnostic accuracy (Table 1). In posttreatment and low-transmission surveillance scenarios, parasitological methods such as HELMINTEX, which exhibit extremely high sensitivity for detecting low egg burdens, should be considered. Additionally, diverse serological assays (e.g., ELISA) widely offered in Brazil play a pivotal role, while serology requires careful interpretation in active transmission areas, it is invaluable for posttreatment monitoring and verifying transmission interruption (4, 5).

Pharmacological intervention within the SUS is centered on praziquantel (PZQ) (Table 2). In strict alignment with the Ministry of Health guidelines (MS, 2024) and WHO protocols, the standardized single oral dose is 50 mg/kg for adults (up to a maximum limit of 3 g) and 60 mg/kg for children (> 2 years old and > 10 kg) (4). The therapeutic dose for pediatric populations is standardized to 60 mg/kg across all clinical workflows. Recent clinical updates have focused on the safety and efficacy of crushed PZQ tablets for preschool-aged children, ensuring that this vulnerable demographic is adequately covered in mass deworming efforts (25). Beyond chemotherapy, the SUS clinical flowchart establishes a rigorous referral system that connects primary health care (PHC) units to high-complexity centers. This integrated care model is designed to manage the severe sequelae of the disease, including ectopic manifestations such as neuroschistosomiasis (schistosomal myeloradiculopathy) and advanced hepatosplenic forms requiring surgical intervention for portal hypertension. This multidisciplinary approach, which combines advanced molecular diagnostics, standardized chemotherapy, and specialized surgical management, forms the cornerstone of the Brazilian strategy to eliminate schistosomiasis as a public health threat by 2030 (8, 20, 23).

Contemporary therapeutic protocols and integrated control strategies for schistosomiasis (2024–2026)

The pharmacological management of schistosomiasis within the Brazilian Unified Health System (SUS) has reached a critical standardization milestone under the 2024 Ministry of Health protocols. Praziquantel (600 mg) is currently established as the exclusive drug of choice, following the formal discontinuation of oxamniquine from the national therapeutic arsenal. The standardized dosing regimen is meticulously calibrated to age-specific pharmacokinetics, requiring a single dose of 50 mg/kg for adults and 60 mg/kg for children over two years of age. This therapeutic consistency is vital for maintaining the efficacy of mass drug administration (MDA) programs in endemic zones, aligning with the World Health Organization’s 2022 guidelines, which expanded eligibility to younger cohorts to suppress the environmental egg burden more effectively. For severe acute manifestations, such as Katayama fever or neurological involvement, the protocol mandates the adjunctive use of corticosteroids to modulate the intense inflammatory response. In advanced chronic cases, particularly the hepatosplenic form, the clinical focus shifts toward managing the sequelae of portal hypertension through endoscopic sclerotherapy or surgical interventions for esophageal varices (20, 26).

In accordance with the One Health (Saúde Única) paradigm, the Brazilian strategy for 2024–2026 acknowledges that pharmacological intervention is insufficient for total elimination without structural environmental reform. The recent implementation of the Brazilian Legal Framework for Sanitation represents a pivotal shift, as it aims to universalize access to potable water and sewage treatment. By reducing the volume of untreated human waste entering freshwater ecosystems, these structural improvements directly interrupt the life cycle of the parasite at the miracidium-to-snail interface. Furthermore, the integration of new communication technologies has modernized health education initiatives. Communities in peri-urban “transmission pockets” are now engaged through digital platforms and mobile health (mHealth) tools, which facilitate real-time reporting of environmental risks and promote behavioral changes regarding water contact, thereby bridging the gap between clinical treatment and long-term prevention (8, 22).

The sustainability of these efforts is reinforced by the shift toward high-sensitivity molecular diagnostics, such as POC-CCA and qPCR, which ensure that MDA is targeted with geographic precision. While repeated chemotherapy cycles have historically been successful in reducing the prevalence of severe hepatosplenic forms, the current triennium emphasizes that the “last mile” toward elimination requires this synergy of universal sanitation, rigorous clinical follow-up for chronic patients, and localized vector control. This integrated approach ensures that the SUS not only manages the existing burden of disease but also systematically eradicates the environmental reservoirs that have sustained schistosomiasis in Brazil for centuries (21, 26).

Malacological surveillance and integrated control strategies for schistosomiasis elimination

The contemporary framework for malacological surveillance and control of schistosomiasis in Brazil is characterized by an integrated approach that harmonizes chemical, environmental, and social interventions. Central to this strategy is the systematic identification of transmission foci and the strategic application of molluskicides, primarily niclosamide. While chemical control remains a cornerstone for reducing intermediate host populations of the genus Biomphalaria, longitudinal studies indicate that gastropod populations often recover following consecutive treatments, a phenomenon that underscores the insufficiency of chemical intervention as a standalone measure. Consequently, modern surveillance has evolved to incorporate advanced molecular techniques, such as the detection of environmental DNA (eDNA). This technology allows for the identification of Schistosoma and its snail hosts within aquatic ecosystems even at low densities, providing health authorities with a high-resolution map of active transmission sites that traditional malacological surveys might overlook (27, 28).

The efficacy of malacological control is profoundly amplified when it is coupled with community-based health education initiatives. These programs are designed to mobilize vulnerable people, fostering a behavioral shift toward avoiding contact with potentially contaminated water bodies. However, the scientific literature suggests that the mere dissemination of information is often insufficient; inadequate baseline knowledge and persistent misconceptions regarding the life cycle of the parasite frequently hinder the effectiveness of educational interventions. Therefore, the current 2024–2026 triennium emphasizes a participatory model of health education that promotes deep community engagement and a clear understanding of the biological risks associated with local environmental features (29). This comprehensive integration of social, clinical, and environmental variables is conceptualized in the integrated One Health framework, detailed in Figure 5, which maps control strategies across the biological cycle.

Ultimately, basic sanitation and environmental management represent the definitive mechanisms for the permanent interruption of the schistosomiasis transmission cycle. While mass drug administration (MDA) with praziquantel is indispensable for reducing immediate morbidity and individual parasite loads, it cannot prevent reinfection in the absence of structural reforms. The implementation of universal access to potable water, efficient sewage drainage, and the permanent modification of snail-breeding habitats, such as the paving of drainage ditches, constitute the only sustainable pathway for medium- and long-term control. Historically successful programs in regions such as China and Egypt have demonstrated that the convergence of environmental engineering, safe water provision, and targeted vector suppression is essential for transitioning from control to total elimination (22, 30, 31).

Environmental management strategies are currently reemerging as critical tools in the “One Health” arsenal. These interventions involve both permanent modifications of the landscape to eliminate stagnant water niches and seasonal infrastructure maintenance to suppress snail proliferation during high-risk periods. By providing a structural barrier between human waste and freshwater ecosystems and between human skin and cercariae-infested water, these measures ensure that the biological cycle of Schistosoma mansoni is physically disrupted. This holistic integration of molecular surveillance, community mobilization, and structural sanitation forms the scientific basis for the Brazilian goal of eliminating schistosomiasis as a public health threat by 2030 (8, 32).

Critical analysis of schistosomiasis persistence: biological resilience and systemic neglect

Despite decades of targeted pharmacological interventions, the persistent endemicity of schistosomiasis is a multifaceted phenomenon rooted in the biological resilience of the intermediate host and the systemic socioeconomic vulnerabilities of affected populations. At the core of this persistence lies the extraordinary adaptive capacity of the gastropod Biomphalaria glabrata. High-resolution genomic analyses have revealed that Biomphalaria glabrata possesses a highly complex and plastic genetic architecture characterized by significant structural diversity and specific gene clusters that modulate susceptibility or resistance to Schistosoma mansoni infection. These genomic variations—particularly within the immune-related regions of the snail—allow the vector to sustain the parasite’s intramolluscan larval development across diverse environmental conditions, thereby ensuring a continuous supply of infective cercariae in endemic water bodies (9, 33, 34).

Beyond the biological prowess of the vector, the categorization of schistosomiasis as a neglected tropical disease (NTD) highlights a critical failure in global and national health priorities. This “negligence” is manifested in the chronic underfunding of large-scale eradication programs and a disproportionate reliance on human chemotherapy at the expense of comprehensive vector control. While mass drug administration effectively reduces morbidity in human hosts, the lack of systematic, long-term suppression of snail populations allows for the rapid recolonization of transmission foci. This cycle of reinfection is further complicated by the high mobility of definitive human hosts, which facilitates the constant introduction of new parasite genotypes into local snail populations, maintaining the genetic diversity and evolutionary vigor of Schistosoma mansoni (35–37).

The maintenance of Biomphalaria glabrata foci is linked to socioeconomic vulnerability and the absence of basic sanitary infrastructure. In many endemic regions of Brazil, the lack of treated water and adequate sewage disposal forces humans to contact stagnant water bodies that serve as ideal ecological niches for intermediate hosts. These environments are characterized by poor drainage and environmental degradation, which promote the accumulation of organic matter and provide the necessary conditions for snail proliferation. The synergy between human poverty and environmental precariousness creates a robust transmission loop that is resistant to purely medical interventions. Research has indicated that social determinants, such as housing quality and access to WASH (water, sanitation, and hygiene) services, are the primary drivers of environmental risk, as they dictate the frequency and intensity of human–vector interactions (38, 39).

Recent advancements in the field of molecular biology have begun to elucidate the intricate “interactome” between Biomphalaria glabrata and Schistosoma mansoni, identifying specific molecular targets that could be exploited for biocontrol. These include gene-editing techniques and RNA interference (RNAi) strategies aimed at reducing the compatibility of the vector with the parasite. However, the transition of these technologies from laboratory to field application remains constrained by ethical, environmental, and financial barriers. Therefore, the persistence of schistosomiasis in the 21st century must be understood as a failure of integrated public policy; until molecular innovations are combined with structural sanitation and the mitigation of socioeconomic inequality, the biological resilience of the snail and the parasite will continue to outpace existing control efforts (9, 39).

Future perspectives and knowledge gaps: beyond the 2030 goal

While the Brazilian roadmap for schistosomiasis elimination is technically grounded, several critical gaps must be addressed to ensure the sustainability of these efforts after 2030:

Precision malacology and green control: Current environmental surveillance relies on labor-intensive malacological surveys. The integration of environmental DNA (eDNA) tools to detect Biomphalaria species and S. mansoni cercariae in water bodies represents a vital frontier for early outbreak detection. Furthermore, as chemical control with niclosamide is highly toxic to nontargeted aquatic biota, the development of eco-friendly, plant-derived molluskicides leveraging agro-industrial byproducts is a strategic necessity within the One Health framework.

The “low-load” diagnostic paradox: As the incidence declines, the proportion of individuals with low parasite loads increases, rendering traditional fecal microscopy (Kato-Katz) technically obsolete for verification of elimination. There is a critical knowledge gap regarding the “gold standard” for post elimination monitoring; future research must evaluate the cost–benefit of large-scale implementation of high-sensitivity assays such as PCR or circulating anodic antigen (CAA) within the SUS laboratory network.

Legacy of morbidity and aging: Eliminating transmission does not immediately resolve the burden of the disease. A significant gap exists in the long-term management of the “morbidity legacy” in the aging cohort–elderly patients who, despite being parasitologically cured, suffer from chronic hepatic complications and portal hypertension.

Biotechnological frontiers: Future strategies must explore the ethical application of novel tools, such as genomic editing of intermediate hosts to reduce vector competence and the development of more palatable pediatric formulations of praziquantel to address treatment gaps in younger demographics.

Reservoir Ecology and One Health: To fully elucidate the complexity of transmission persistence, additional research must focus on evaluating the natural infection rates and reproductive viability of S. mansoni in wild rodents (Nectomys squamipes and Holochilus hydrius) in urban and peri-urban areas to determine their ability to maintain wild transmission cycles independently.

The ultimate elimination of schistosomiasis as a public health threat in Brazil necessitates an immediate paradigm shift toward a highly integrated model that synthesizes rigorous clinical vigilance with structural environmental reform. The transition from a morbidity control paradigm to total transmission interruption requires that pharmacological interventions be inextricably coupled with the universalization of basic sanitation and a safe water supply, as mandated by the Brazilian Legal Framework for Sanitation.

Sustained fiscal investment and political will are essential not only for the procurement of next-generation diagnostics but also for maintaining a multidisciplinary workforce capable of conducting sophisticated surveillance. Ultimately, elimination of schistosomiasis is not merely a pharmacological challenge; it is a social and environmental imperative. Only through a steadfast commitment to the “One Health” approach addressing biological, environmental, and socioeconomic determinants in a unified manner can Brazil secure a future free from the burden of this neglected tropical disease.