[Schistosomiasis in areas of low endemicity: an overly neglected disease. The example of Schistosoma monsoni in BrazilEsquistossomose em áreas de baixa endemicidade, uma doença muito negligenciada. O exemplo de Schistosoma mansoni no Brasil]. / La schistosomose dans les zones de faible endémicité, une maladie trop négligée. Le cas de Schistosoma monsoni au Brésil.

Human schistosomiasis is a parasitic disease caused by an infection with trematodes of the genus Schistosoma. The disease mainly affects impoverished populations. Around 800 million people are exposed to the infection, which is a public health problem in the tropical and subtropical regions of Africa, Asia, the Caribbean and South America. In Brazil, Schistosoma mansoni is the only species that causes schistosomiasis and the disease is widely distributed. Conventional diagnosis of the disease is carried out by detecting eggs using parasitological methods, such as the Kato-Katz test. Schistosomiasis has been reported in all regions of Brazil and is characterized as endemic in seven states in the Northeast Region and two states in the Southeast Region. In 2015, 78,7% of all cases reported in Brazil occurred in the Northeast Region. It is estimated that 1,5 million people is infected with this disease in Brazil and more than 25 millions live in areas with a high risk of transmission. Despite the reduction in mortality and morbidity, schistosomiasis was responsible for 8,756 deaths between 2000 and 2011 and 2,517 deaths between 2015 and 2019 in Brazil and it remains an important public health problem. In the state of Rio de Janeiro, some areas have low endemicity or isolated foci of Schistosoma mansoni and the majority of infected individuals have mild infections. The last survey of the disease in the state of Rio de Janeiro was carried out between 2010 and 2015 in students aged 7 to 17.Schistosomiasis was reported in 10 of the 21 municipalities studied. Of the 5,111 school children screened for S. mansoni infection, 46 (1,65%) were tested positive. Studies carried out in areas of low endemicity in Rio de Janeiro showed that among the 205 patients infected by S. mansoni in Sumidouro, around 84% were aged 14 or over and all, except one individual, had the intestinal form (91,2%) or hepato-intestinal (8,3%) of schistosomiasis. Another study carried out in Sumidouro showed that with tests based on patent Schistosoma egg infection determined by the Kato-Katz test, active infections were diagnosed in eight (8/108) individuals. The intensity of infection expressed by parasite loads ranged from 6 to 72 eggs per gram of feces/individual. The results showed DNA amplification in 32 of the 100 individuals tested by real-time PCR. All individuals with patent ovo infection showed positive DNA amplification. These studies showed that if we only analyzed school-age children using the Kato-Katz test, the majority of the infected population would never be diagnosed with S. mansoni infection. In situations of low endemicity, with low intensities of infection, with low severity in the population and in the most affected age groups, schistosomiasis requires a more sensitive diagnostic approach (e.g. screening by PCR rather than Kato test), otherwise many infected individuals will remain invisible to the healthcare system.

A esquistossomose humana é uma doença parasitária causada por uma infecçâo por vermes sanguíneos do gènero Schistosoma. A doença afeta principalmente populaçoes empobrecidas. Cerca de 800 milhoes de pessoas estâo expostas à infecçâo, sendo um problema de saúde pública nas regioes tropicais e subtropicais de África, Ásia, Caribe e América do Sul. No Brasil, o Schistosoma mansoni é a única espécie causadora da esquistossomose e a doença é amplamente distribuida. O diagnóstico convencional da doença é realizado pela detecçâo dos ovos através de métodos parasitológicos, como o teste de Kato-Katz. A esquistossomose foi notificada em todas as regioes do Brasil, e é caracterizada como endèmica em sete estados da Regiâo Nordeste e dois estados da Regiâo Sudeste. Em 2015, 78,7% de todos os casos notificados no Brasil ocorreram na Regiâo Nordeste. Estima-se que 1,5 milhâo de pessoas estejam infectadas com esta doença no Brasil e mais de 25 milhoes vivam em áreas com alto risco de transmissâo. Apesar da reduçâo da mortalidade e morbidade, a esquistossomose foi relatada em 8.756 mortes entre 2000 e 2011 e em 2.517 mortes entre 2015 e 2019 no Brasil e continua sendo um importante problema de saúde pública. No Estado do Rio de Janeiro, algumas áreas apresentam baixa endemicidade ou focos isolados de Schistosoma mansoni e a maioria dos individuos infectados apresenta infecçoes leves. O último levantamento da doença no Estado do Rio de Janeiro foi realizado entre 2010 e 2015 em estudantes de 7 a 17 anos. A esquistossomose foi relatada em 10 dos 21 municipios estudados. Das 5.111 crianças escolares triadas para infecçâo por S. mansoni, 46 (1,65%) testaram positivo. Estudos realizados em áreas de baixa endemicidade no Rio de Janeiro mostraram que dentre os 205 pacientes infectados por S. mansoni em Sumidouro, cerca de 84% tinham 14 anos ou mais e todos, exceto um individuo, tinham a forma intestinal (91,2%) ou hepato-intestinal (8,3%) da esquistossomose. Outro estudo realizado em Sumidouro, mostrou que testes baseados em infecçâo patente de ovo de Schistosoma determinada pelo teste de Kato-Katz, infecçoes ativas foram diagnosticadas em oito (8/108) individuos. A intensidade de infecçâo expressa pelas cargas parasitárias variou de 6 a 72 ovos por grama de fezes/individuo. Os resultados mostraram amplificaçâo do DNA em 32 dos 100 individuos testados por PCR em tempo real. Todos os indivíduos com infecçâo ovo-patente apresentaram amplificaçâo de DNA positiva. Tais estudos mostraram que se analisarmos apenas crianças em idade escolar pelo teste de Kato-Katz, a maioria da populaçâo infectada nunca seria diagnosticada com infecçâo pelo S. mansoni. Em situaçoes de baixa endemicidade, com baixas intensidades de infecçâo, com baixa gravidade na populaçâo e nas faixas etárias mais afetadas, a esquistossomose requer uma abordagem diagnóstica mais sensivel (por exemplo, triagem por PCR em vez do teste de Kato), caso contràrio, muitos individuos infectados permanecerâo invisiveis para o sistema de saúde.

Functional autoantibodies against G protein-coupled receptors in hepatic and pulmonary hypertensions in human schistosomiasis.

Introduction: Schistosomiasis (SM) is a parasitic disease caused by Schistosoma mansoni. SM causes chronic inflammation induced by parasitic eggs, with collagen/fibrosis deposition in the granuloma process in the liver, spleen, central nervous system, kidneys, and lungs. Pulmonary arterial hypertension (PAH) is a clinical manifestation characterized by high pressure in the pulmonary circulation and right ventricular overload. This study investigated the production of functional autoantibodies (fAABs) against the second loop of the G-protein-coupled receptor (GPCR) in the presence of hepatic and PAH forms of human SM. Methods: Uninfected and infected individuals presenting acute and chronic manifestations (e.g., hepatointestinal, hepato-splenic without PAH, and hepato-splenic with PAH) of SM were clinically evaluated and their blood was collected to identify fAABs/GPCRs capable of recognizing endothelin 1, angiotensin II, and a-1 adrenergic receptor. Human serum was analyzed in rat cardiomyocytes cultured in the presence of the receptor antagonists urapidil, losartan, and BQ123. Results: The fAABs/GPCRs from chronic hepatic and PAH SM individuals, but not from acute SM individuals, recognized the three receptors. In the presence of the antagonists, there was a reduction in beating rate changes in cultured cardiomyocytes. In addition, binding sites on the extracellular domain functionality of fAABs were identified, and IgG1 and/or IgG3 antibodies were found to be related to fAABs. Conclusion: Our data suggest that fAABs against GPCR play an essential role in vascular activity in chronic SM (hepatic and PAH) and might be involved in the development of hypertensive forms of SM.

Challenges to Schistosomiasis Control Program in Brazil: setbacks in the control program and critical analysis of the disease notification.

BACKGROUND: In 1970, Brazil implemented the Schistosomiasis Control Program (PCE, Portuguese acronym for Programa de Controle da Esquistossomose) was implemented in Brazil, where, through successive treatment interventions, the epidemiology and transmission of schistosomiasis have changed significantly over time. This study aimed to evaluate the PCE's effectiveness by critically analyzing the disease notification system. METHODS: An ecological study was conducted using data on reported schistosomiasis cases in Brazil between 2007 and 2020. RESULTS: The highest number of municipalities actively participating in the PCE was 750, recorded in 2007. Conversely, participation reached its lowest point in 2020, with only 259 municipalities involved. Over the past decade, there has been a drastic decline in the number of municipalities with active schistosomiasis control programs. During the same period, there was an observed increase in the number of deaths caused by schistosomiasis, while the number of reported cases decreased. This suggests an inverse correlation. CONCLUSIONS: The present data suggest that schistosomiasis cases are not correctly diagnosed or reported, reflecting a twisted image of the magnitude of this public health problem in Brazil.

Portal thrombosis after surgical treatment of schistosomatic portal hypertension.

OBJECTIVE: Several studies have investigated the correlation between the effects of different surgical treatments and laboratory exams for schistosomal portal hypertension, especially concerning portal system thrombosis. The etiopathogenic factors of this thrombosis are not fully understood. In this study, the correlation between surgical treatment for schistosomal portal hypertension and the occurrence of postoperative portal system thrombosis was investigated. METHODS: A total of 61 patients who underwent surgical treatment for schistosomal portal hypertension were distributed into four groups: Patients in Group 1 (n=12) underwent portal variceal disconnection associated with splenic artery ligation and spleen preservation. Patients in Group 2 (n=20) underwent portal variceal disconnection and total splenectomy. Patients in Group 3 (n=20) underwent portal variceal disconnection with subtotal splenectomy, preserving the upper splenic pole supplied by the splenogastric vessels. Patients in Group 4 (n=9) underwent portal variceal disconnection with total splenectomy and autogenous splenic implants on the greater omentum. Late postoperative portal vein thrombosis was diagnosed using Doppler ultrasound. RESULTS: Over the 10-year follow-up, portal vein thrombosis occurred in 26 operated patients (42.6%), with no significant difference observed among the four surgical groups (p=0.217). Most of the thrombi only partially occluded the portal system veins. All the patients presented with a thrombus inside the portal vein. There was no difference in hematological and biochemical tests between groups with or without portal vein thrombosis. CONCLUSIONS: Portal vein thrombosis is often observed in the late postoperative period, irrespective of the surgical treatment employed, and is not associated with patient characteristics or any hematological and biochemical tests.

The COVID-19 pandemic impacted the activities of the Schistosomiasis Control Program in Brazil: is the goal of controlling the disease by 2030 at risk?

BACKGROUND: Schistosomiasis continues to represent a serious public health problem in Brazil. With the coronavirus disease 2019 (COVID-19) pandemic, several control strategies were suspended, probably compromising the goals of eradicating the disease in the country. We aimed to assess the impact of the COVID-19 pandemic on Schistosomiasis Control Program (PCE) actions in all endemic states of Brazil. METHODS: We performed an ecological study using spatial analysis techniques. The PCE variables assessed were the population surveyed, the number of Kato-Katz tests, positive cases of schistosomiasis and the percentage of cases treated between 2015 and 2021. The percent change was calculated to verify if there was an increase or decrease in 2020 and 2021, along with time trend analyses provided by the Joinpoint model. Spatial distribution maps were elaborated considering the percent change. RESULTS: The surveyed population decreased in 2020 (-65.38%) and 2021 (-37.94%) across Brazil. There was a proportional reduction in the number of Kato-Katz tests (2020, -67.48%; 2021, -40.52%), a decrease in the percentage of positive cases (2020, -71.16%; 2021, -40.5%) and a reduction in the percentage of treated cases (2020, -72.09%; 2021, -41.67%). Time trend analyses showed a decreasing trend in most PCE variables. CONCLUSIONS: The PCE activities were impacted by the COVID-19 pandemic in Brazil and PCE strategies must be urgently reviewed, focusing on investments in all endemic areas.

Prevalence of helmintic infections in Brazilian Maxakali indigenous: a repeated cross-sectional design.

BACKGROUND: The prevalence of intestinal parasites is known to be high among Amerindian populations; further, there are serious problems in the healthcare of these populations in Brazil. The Maxakali, located in the northeastern region of Minas Gerais, Brazil, is an indigenous group that still preserves many of its cultural aspects. This study aimed to compare the positivity rate of schistosomiasis and soil-transmitted helminths in this ethnic group in epidemiological surveys conducted in 1972 and 2014. METHODS: Stool parasitological examinations were performed by the Kato-Katz technique during both periods in this population. In 2014, the parasitological diagnosis was also realized with the TF-Test® technique. RESULTS: In 1972, 270 inhabitants were examined. The positivity rates were 67.4% for Schistosoma mansoni, 72.9% for hookworms, 43.7% for Ascaris lumbricoides, and 23.7% for Trichuris trichiura. In 2014, 545 individuals were examined, and the positivity rates obtained were 45.7% for S. mansoni, 22.8% for hookworms, 0.6% for A. lumbricoides, and 2.8% for T. trichiura. CONCLUSIONS: The comparison of the parasitological surveys conducted in 1972 and 2014, indicates that the indigenous Maxakali remained neglected by the health and indigenous protection authorities during these four decades. The infection rate observed in 2014 for schistosomiasis and hookworm remains high, considering the current epidemiological view of these diseases in the Brazilian population.

Malacological, socio-environmental evaluation, and evidence of local transmission and maintenance of schistosomiasis in an urban area of Northeast Brazil.

To present the current epidemiological scenario of schistosomiasis related to urban transmission through an epidemiological risk assessment in Porto de Galinhas, a coastal area of Pernambuco, Brazil. Malacological and parasitological surveys were performed between the years 2018 and 2020. Snails were identified taxonomically and examined to confirm infection by Schistosoma mansoni, and so to identify Schistosomiasis Transmission Foci (STF) by the artificial light exposure technique. Stool samples were examined using the Kato-Katz method to identify schistosomiasis cases. Socioeconomic, environmental, behavioural and health data were collected by a questionnaire applied to participates in the survey and used to predict the schistosomiasis risk occurrence by multivariate logistic regression. In all, a total of 6466 snails of Biomphalaria glabrata were collected and 36 breeding sites were identified, of which 25 % were STF. A total of 2236 individuals took part of the survey which identified 187 cases of schistosomiasis, registering a positivity percentage of 8.36 %. The surveys identified the neighbourhoods with the highest risk for transmission while the socioenvironmental analysis identifies other risk factors for disease occurrence, such as gender, age range, level of education and absence of water drainage. We found that areas with poor sanitation, flooding during winter periods and dwellings located near mangroves should be treated by health authorities as priority areas for health interventions to minimize disease transmission. In addition, efforts to improve the population's educational level could certainly contribute to the adoption of measures to prevent and control this neglected tropical disease.

Dietary glycemic and energy load differentially modulates Schistosoma mansoni-induced granulomatous inflammation and response to antiparasitic chemotherapy.

The impact of diet composition and energy content on schistosomiasis evolution and treatment efficacy is still controversial. This study compared the impact of sucrose-rich diet and intermittent fasting on Schistosoma mansoni infection and praziquantel (PZQ)-based chemotherapy response in mice. BALB/c mice were infected with S. mansoni and followed for 15 weeks. The animals were randomized into nine groups receiving high glycemic load (high-sucrose diet - HSD), low caloric load (standard chow alternate-day fasting - ADF), and standard chow ad libitum (AL). Eight weeks after S. mansoni infection, these groups remained untreated or were treated with PZQ (300 mg/kg/day) for 3 days. Our results indicated that parasite load (S. mansoni eggs and parasite DNA levels), granulomatous inflammation (granulomas number and size), and liver microstructural damage (reduction in hepatocytes number, increase in nucleus-cytoplasm ratio, connective stroma expansion and fibrosis) were increased in ADF-treated animals. These animals also showed decreased eggs retention, granulomatous inflammation and collagen accumulation in the small intestine. Conversely, HSD diet and PZQ treatment attenuated all these parameters and stimulated hepatic regenerative response. PZQ also stimulated fibrosis resolution in HSD-treated mice, effect that was limited ADF-exposed mice. Our findings indicate that dietary glycemic and energy load can modulate schistosomiasis progression and the severity of hepatic and intestinal granulomatous inflammation in untreated and PZQ-treated mice. Thus, lower intestinal eggs retention may potentially be linked to worsening liver disease in ADF, while attenuation of hepatic and intestinal granulomatous inflammation is consistent with reduced parasite load in HSD- and PZQ-treated animals.

Accuracy of commercial ELISA and ICT for screening schistosomiasis infections at a low endemicity area in Brazil.

BACKGROUND: Control interventions recommended by the World Health Organization have successfully resulted in low-intensity schistosomiasis transmission areas. To achieve elimination of transmission, new diagnostic screening tools are needed to overcome less than adequate sensitivity of the currently used Kato-Katz faecal thick smear method. Ideally, in-house serological tests should be avoided due to not having a continuous supply of kits as would be necessary for large population studies. Quality assurance provided by manufacturers and proper performance evaluations are also needed. We evaluated the accuracy of two commercially available serology tests as screening methods for detecting light schistosomiasis infections. METHODS: Serum samples were collected in 2015 from individuals living in a low-endemicity locality in northeastern Brazil and deposited in a biorepository. We evaluated immunoglobulin G (IgG) and IgM enzyme-linked immunosorbent assays (ELISAs) and an immunochromatographic test (ICT). The Helmintex method was used to define true-positive samples. RESULTS: Overall sensitivity was close to 90% for both the IgG ELISA and ICT, yet specificity was 28% and 18%, respectively. For the IgM ELISA, the values were estimated to be 55% and 43%, respectively. CONCLUSIONS: Poor specificity and positive predictive values prevent these tests from being recommended for screening populations in low-intensity schistosomiasis-endemic areas.

Fragment library screening by X-ray crystallography and binding site analysis on thioredoxin glutathione reductase of Schistosoma mansoni.

Schistosomiasis is caused by parasites of the genus Schistosoma, which infect more than 200 million people. Praziquantel (PZQ) has been the main drug for controlling schistosomiasis for over four decades, but despite that it is ineffective against juvenile worms and size and taste issues with its pharmaceutical forms impose challenges for treating school-aged children. It is also important to note that PZQ resistant strains can be generated in laboratory conditions and observed in the field, hence its extensive use in mass drug administration programs raises concerns about resistance, highlighting the need to search for new schistosomicidal drugs. Schistosomes survival relies on the redox enzyme thioredoxin glutathione reductase (TGR), a validated target for the development of new anti-schistosomal drugs. Here we report a high-throughput fragment screening campaign of 768 compounds against S. mansoni TGR (SmTGR) using X-ray crystallography. We observed 49 binding events involving 35 distinct molecular fragments which were found to be distributed across 16 binding sites. Most sites are described for the first time within SmTGR, a noteworthy exception being the "doorstop pocket" near the NADPH binding site. We have compared results from hotspots and pocket druggability analysis of SmTGR with the experimental binding sites found in this work, with our results indicating only limited coincidence between experimental and computational results. Finally, we discuss that binding sites at the doorstop/NADPH binding site and in the SmTGR dimer interface, should be prioritized for developing SmTGR inhibitors as new antischistosomal drugs.

In Situ Preparation of Dehydrodieugenol-Loaded Silver Nanoparticles and their Antischistosomal Activity.

Schistosomiasis is a major neglected disease that imposes a substantial worldwide health burden, affecting approximately 250 million people globally. As praziquantel is the only available drug to treat schistosomiasis, there is a critical need to identify new anthelmintic compounds, particularly from natural sources. To enhance the activity of different natural products, one potential avenue involves its combination with silver nanoparticles (AgNP). Based on this approach, a one-step green method for the in situ preparation of dehydrodieugenol (DHDG) by oxidation coupling reaction using silver and natural eugenol is presented. AgNP formation was confirmed by UV-Vis spectroscopy due to the appearance of the surface plasmon resonance (SPR) band at 430 nm which is characteristic of silver nanoparticles. The nanoparticles were spherical with sizes in the range of 40 to 50 nm. Bioassays demonstrated that the silver nanoparticles loaded with DHDG exhibited significant anthelmintic activity against Schistosoma mansoni adult worms without toxicity to mammalian cells and an in vivo animal model (Caenorhabditis elegans), contributing to the development of new prototypes based on natural products for the treatment of schistosomiasis.

Matrix metalloproteinases inhibition reveals the association between inflammation, collagen accumulation and intestinal translocation of Schistosoma mansoni eggs in vivo.

Schistosomiasis mansoni is a parasitic infection that causes enterohepatic morbidity associated with severe granulomatous inflammation triggered by parasite eggs. In this disease, granulomatous inflammation leads to intestinal erosion and environmental excretion of S. mansoni eggs from feces, an essential process for propagating the parasite and infecting host organisms. Metalloproteinases (MMP) are involved in S. mansoni-induced hepatic granulomatous inflammation and fibrosis. However, the relationship between MMP and collagen accumulation with the intestinal excretion of parasite eggs remains unclear. Thus, the present study investigated whether MMP inhibition is capable of modulating granulomatous inflammation, collagen accumulation and mechanical resistance to the point of influencing the dynamics between intestinal retention and excretion of S. mansoni eggs in infected mice. Our findings indicated that doxycycline (a potent MMP inhibitor) aggravates intestinal inflammation and subverts collagen dynamics in schistosomiasis. By attenuating MMP-2 and MMP-9 activity, this drug is capable of enhancing fibrosis and mechanical resistance of the intestinal wall, hindering S. mansoni eggs translocation. Although collagen content was not correlated with MMP activity, intestinal retention and fecal excretion of parasite eggs in untreated mice; these correlations were observed for doxycycline-treated animals. Thus, our study provides evidence that doxycycline is able to attenuate fecal elimination of S. mansoni eggs by inhibiting MMP-2 and MMP-9 activity, events potentially associated with excessive collagen accumulation, which increases intestinal mechanical resistance and hinders eggs translocation through the intestinal wall. Variations in intestinal collagen dynamics are relevant since they may represent changes in the environmental dispersion of S. mansoni eggs, bringing repercussions for schistosomiasis propagation.

Development and evaluation of the in vitro schistosomicidal activity of solid dispersions based on 2-(-5-bromo-1-H-indole-3-yl-methylene)-N-(naphthalene-1-ylhydrazine-carbothiamide.

Among all the neglected diseases, schistosomiasis is considered the second most important parasitic infection after malaria. Praziquantel is the most widely used drug for this disease, but its exclusive use may result in the development of drug-resistant schistosomiasis. To increase the control of the disease, new drugs have been developed as alternative treatments, among them 2-(-5-bromo-1-h-indole-3-yl-methylene)-N-(naphthalene-1-ylhydrazine-carbothiamide (LQIT/LT-50), which showed promising schistosomicidal activity in nonclinical studies. However, LQIT/LT-50 presents low solubility in water, resulting in reduced bioavailability. To overcome this solubility problem, the present study aimed to develop LQIT/LT-50 solid dispersions for the treatment of schistosomiasis. Solid dispersions were prepared through the solvent method using Soluplus©, polyethylene glycol (PEG) or polyvinylpyrrolidone (PVP K-30) as hydrophilic carriers. The formulations with the best results in the compatibility tests, aqueous solubility and preliminary stability studies have undergone solubility tests and physicochemical characterizations by Fourier-transform infrared spectroscopy (FTIR), x-ray diffractometry (XRD), exploratory differential calorimetry (DSC), thermogravimetry (TG) and Raman spectroscopy. Finally, the schistosomicidal activity was evaluated in vitro. The phycochemical analyzes showed that when using PVP K-30, there was an interaction between the PVP K-30 and LQIT/LT-50, proving the successful development of the solid dispersion. Furthermore, an increase in the solubility of the new system was observed (LQIT/LT-50:PVP K-30) in addition to the improvement in the in vitro shistosomidal activity at 1:4 (w/w) molar ratio (i.e., 20% drug loading) when compared to LQIT/LT-50 alone. The development of the LQIT/LT-50:PVP K-30 1:4 solid dispersion is encouraging for the future development of new pharmaceutical solid formulations, aiming the schistosomicidal treatment.

Schistosomiasis: A neglected cause of pulmonary arterial hypertension in Brazil.

Schistosomiasis is a prevalent disease in Brazil whose etiological agent is Schistosoma mansoni, the main species associated with pulmonary arterial hypertension (PAH), a serious complication. It is estimated that this complication affects up to 15% of patients with the hepatosplenic form of the disease. Despite being an endemic country, Brazil does not have a screening scheme for cases of PAH associated with schistosomiasis (PAH-Sch), nor protocols for notification and treatment of this vascular complication. The objectives of this literature review are to gather knowledge about the pathophysiology, clinical manifestations, diagnosis and treatment of PAH-Sch and to highlight relevant aspects for the Brazilian reality. The pathophysiology, although lacking information, has proliferative vasculopathy as a central element. The clinical presentation of this disease can be asymptomatic or with nonspecific manifestations. Thus, complementary exams are essential for a confirmatory diagnosis, the gold standard being right heart catheterization, a scarce resource in endemic regions of the country. The treatment of PAH-Sch is similar to that performed for other causes of PAH, but the impact of anthelmintic therapy on the evolution of the vascular pathology is unknown. Therefore, Brazil needs to develop a screening plan for early diagnosis of PAH-Sch and new studies should be carried out to determine a more specific treatment.

Atuação da atenção primária em saúde para o enfrentamento da esquistossomose mansônica: uma revisão sistemática no Brasil / Action of primary health care for the coping of schistosomiasis mansoni: a systematic review in Bra-zil / Acción de la atención primaria de salud para combatir la esquistosomiasis mansoni: una revisión sis-temática en Brasil

Objetivo: Investigar, estimar e diagnosticar a atuação da Atenção Primária a Saúde (APS) no enfrentamento da esquistossomose mansônica no Brasil. Métodos: Trata-se de um estudo de revisão sistemática para avaliar a atuação da APS no contexto da esquistossomose, desde a criação do Programa de Agentes Comunitários de Saúde (PACS). Os dados foram obtidos por meio da metodologia do PRISMA (1991- abril/ 2021). Resultados: A busca identificou 14 trabalhos, a maioria desenvolvida no estado de Pernambuco. Os achados deste estudo mostram um quantitativo relativamente baixo de trabalhos abordando a Atenção Primária como principal política de saúde de cuidados básicos para esquistossomose, assim como a fragilidade de articulação da vigilância com a APS. Conclusões: Identificou-se a necessidade de mais estudos que discutam a APS como importante nível de atenção e estratégia viável para o controle da esquistossomose, que ainda mantém ações incipientes contribuindo para que a doença persista como um problema de saúde pública no Brasil (AU).

Objective: To investigate, estimate and diagnose the role of Primary Health Care (PHC) in coping with schistosomiasis mansoni in Brazil. Methods: This is a systematic review study to evaluate the performance of PHC in the context of schistosomiasis, since the creation of the Community Health Agents Program (PACS). Data were obtained using the PRISMA methodology (1991-April/2021). Results: The search identified 14 works, most of them developed in the state of Pernambuco. The findings of this study show a relatively low number of studies addressing Primary Care as the main health policy for basic care for schistosomiasis, as well as the fragility of articulation between surveillance and PHC. Conclusions: It was identified the need for more studies that discuss PHC as an important level of care and a viable strategy for the control of schistosomiasis, which still maintains incipient actions contributing to the disease persisting as a public health problem in Brazil (AU).

Objetivo: investigar, estimar y diagnosticar el papel de la Atención Primaria de Salud (APS) en el enfrentamiento de la esquistosomiasis mansoni en Brasil. Métodos: Se trata de un estudio de revisión sistemática para evaluar el desempeño de la APS en el contexto de la esquistosomiasis, desde la creación del Programa de Agentes Comunitarios de Salud (PACS). Los datos se obtuvieron mediante la metodología PRISMA (1991-abril/2021). Resultados: La búsqueda identificó 14 obras, la mayoría desarrolladas en el estado de Pernambuco. Los hallazgos de este estudio muestran un número relativamente bajo de estudios que abordan la Atención Primaria como la principal política de salud para la atención básica de la esquistosomiasis, así como la fragilidad de la articulación entre la vigilancia y la APS. Conclusiones: Se identificó la necesidad de más estudios que discutan la APS como un importante nivel de atención y una estrategia viable para el control de la esquistosomiasis, que aún mantiene acciones incipientes contribuyendo a que la enfermedad persista como problema de salud pública en Brasil (AU).

FioSchisto's expert perspective on implementing WHO guidelines for schistosomiasis control and transmission elimination in Brazil.

The World Health Organization (WHO) recognizes schistosomiasis as one of the Neglected Tropical Diseases targeted for global elimination in the 2030 Agenda of the Sustainable Development Goals. In Brazil, schistosomiasis mansoni is considered a public health problem, particularly prevalent among vulnerable populations living in areas with poor environmental and sanitary conditions. In 2022, the WHO published a Guideline encompassing recommendations to assist national programs in endemic countries in achieving morbidity control, eliminating schistosomiasis as a public health problem, and advancing towards interrupting transmission. The perspectives presented here, collectively prepared by members of the Oswaldo Cruz Foundation's (Fiocruz) Schistosomiasis Translational Program (FioSchisto), along with invited experts, examine the feasibility of the WHO recommendations for the Brazilian settings, providing appropriate recommendations for public health policies applicable to the epidemiological reality of Brazil, and suggests future research to address relevant issues. In Brazil, the provision of safe water and sanitation should be the key action to achieve schistosomiasis elimination goals. The agencies involved in measures implementation should act together with the Primary Care teams for planning, executing, monitoring, and evaluating actions in priority municipalities based on their epidemiological indicators. Host snails control should prioritize judicious ecological interventions at breeding sites. The Information, Education, and Communication (IEC) strategy should be associated with water and sanitation and other control actions, actively involving school community. To identify infected carriers, FioSchisto recommends a two-stage approach of immunological and molecular tests to verify transmission interruption during the intervention and beyond. Praziquantel administration should be done under medical supervision at the Primary Care level. MDA should be considered in exceptional settings, as a measure of initial attack strategy in locations presenting high endemicity, always integrated with water and sanitation, IEC, and snail control. To assist decision-making, as well as the monitoring and evaluation of strategic actions, there is a need for an Information System. FioSchisto considers this systematization essential to make investments in strategic research to support the improvement of schistosomiasis control actions. Efforts toward schistosomiasis elimination in Brazil will succeed with a paradigm shift from the vertical prescriptive framework to a community-centered approach involving intersectoral and interdisciplinary collaboration.