Documento de consenso para el manejo de la esquistosomiasis en atención primaria / Consensus document for the management of schistosomiasis in Primary Care

La esquistosomiasis humana es la enfermedad parasitaria con mayor morbimortalidad a nivel mundial después de la malaria. Es endémica en más de 78 países tropicales y subtropicales, sobre todo de África Subsahariana, estimándose que 236 millones de personas están infectadas. Puede causar graves complicaciones de salud a nivel genitourinario y hepatoesplénico, llegando a ocasionar la muerte de 300.000 personas cada año. El número de casos importados en los países occidentales se ha ido incrementado en los últimos años debido a la llegada de un importante número de migrantes procedentes de regiones endémicas y de un creciente número de viajeros que han visitado las mismas. Por otro lado, recientemente se han comunicado brotes de transmisión autóctona en Córcega (Francia) y Almería (España). Por todos estos aspectos, las autoridades sanitarias europeas han recomendado el cribado serológico de la enfermedad en todas las personas migrantes procedentes de zonas endémicas y que lleven menos de 5 años en Europa. Dado que atención primaria es habitualmente el primer punto de contacto de estas personas con el sistema sanitario, los médicos deben conocer los principales aspectos de la enfermedad, y ser dotados de los medios necesarios para su diagnóstico y tratamiento. Este documento ha sido elaborado por profesionales pertenecientes a 5 sociedades científicas de atención primaria (SEMFyC, SEMG, SEMERGEN), Pediatría (SEIP) y Medicina Tropical y Salud Internacional (SEMTSI), con objeto de establecer unas recomendaciones claras para el diagnóstico y el manejo de la esquistosomiasis en atención primaria.(AU)

Human schistosomiasis is the parasitic disease with the highest morbidity and mortality worldwide after malaria. It is endemic in more than 78 tropical and subtropical countries, especially in sub-Saharan Africa, and it is estimated that 236 million people are infected. It can cause serious health complications at the genitourinary and hepatosplenic level, leading to the death of 300,000 people each year. The number of imported cases in Western countries has increased in recent years due to the arrival of a significant number of migrants from endemic regions and a growing number of travelers who have visited them. On the other hand, outbreaks of autochthonous transmission have recently been reported in Corsica (France) and Almería (Spain). For all these reasons, the European health authorities have recommended serological screening for the disease in all migrants from endemic areas who have been living in Europe for less than 5 years. Since Primary Care is usually the first point of contact for these people with the Health System, doctors must know the main aspects of the disease, and be provided with the necessary means for its diagnosis and treatment. This document has been prepared by professionals belonging to five scientific societies of Primary Care (SEMFyC, SEMG, SEMERGEN), Pediatrics (SEIP) and Tropical Medicine and International Health (SEMTSI), in order to establish clear recommendations for the diagnosis and management of schistosomiasis in Primary Care.(AU)

Imported Schistosomiasis, China, 2010-2018.

China has made remarkable progress in reducing schistosomiasis caused by Schistosoma japonicum over the past 7 decades but now faces a severe threat from imported schistosomiasis. Results from national surveillance during 2010-2018 indicate integrating active surveillance into current surveillance models for imported cases is urgently needed to achieve schistosomiasis elimination in China.

Intestinal parasites including Cryptosporidium, Cyclospora, Giardia, and Microsporidia, Entamoeba histolytica, Strongyloides, Schistosomiasis, and Echinococcus: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice.

These updated guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation review the diagnosis, prevention, and management of intestinal parasites in the pre- and post-transplant period. Intestinal parasites are prevalent in the developing regions of the world. With increasing travel to and from endemic regions, changing immigration patterns, and the expansion of transplant medicine in developing countries, they are increasingly recognized as a source of morbidity and mortality in solid-organ transplant recipients. Parasitic infections may be acquired from the donor allograft, from reactivation, or from de novo acquisition post-transplantation. Gastrointestinal multiplex assays have been developed; some of the panels include testing for Cryptosporidium, Cyclospora, Entamoeba histolytica, and Giardia, and the performance is comparable to conventional methods. A polymerase chain reaction test, not yet widely available, has also been developed to detect Strongyloides in stool samples. New recommendations have been developed to minimize the risk of Strongyloides donor-derived events. Deceased donors with epidemiological risk factors should be screened for Strongyloides and recipients treated if positive as soon as the results are available. New therapeutic agents and studies addressing the optimal treatment regimen for solid-organ transplant recipients are unmet needs.

Schistosomiasis infection in pre-school aged children in Uganda: a qualitative descriptive study to identify routes of exposure.

BACKGROUND: Prevalence of schistosomiasis is high among children under five years in Uganda. Schistosomiasis control efforts over time have included periodic mass treatments in endemic areas for adults and school going children aged 5 years and above. This study explores behaviour practices of children age 2-4 years that increase the risk of schistosomiasis infection in this age group. METHODS: A qualitative descriptive study was conducted using in-depth interviews with 30 caregivers of children aged 2-4 years who tested positive for schistosomiasis in a national prevalence survey in 2017. Observations were done at water bodies where young children go with caretakers or other older children. The study was conducted in three Ugandan sub-regions of West Nile and East-central, and South-western with high, and low prevalence of schistosomiasis, respectively. Data were thematically analysed. Anonymised supporting photos from observations are also presented. RESULTS: Knowledge about schistosomiasis transmission was poor among caregivers, who concurrently had mixed right and wrong information. Reported avenues for contracting schistosomiasis included both correct: contact activities with infested water, and incorrect modes: contact with dirty water, sharing bathrooms, witchcraft, polluted air and contaminated food. The children in this study could have contracted schistosomiasis through the contact with infested water during activities such as bathing and playing, while their caregivers washed clothes, collected snail shells for poultry feeds, fetched water at the water bodies. These activities were reported by caregivers and observed in all study areas. Evidence of open defecation and urination in and near water bodies by adults and children was also observed. CONCLUSIONS: Pre-school children age 2-4 years are at a high risk of exposure to schistosomiasis while caretakers conduct activities in infested water bodies. There is need for prevention interventions to target children in their early stages of life to control schistosomiasis in this vulnerable population.

Prevalence and risk factors of bovine schistosomiasis in Northwestern Ethiopia.

BACKGROUND: Parasitic diseases remain major bottle neck to livestock development in developing nations. The objective of this study was to determine the prevalence and associated risk factors of Bovine Schistosomiasis (BS) in South Achefer District, northwestern Ethiopia. METHODS: A cross-sectional copro-parasitological and observational study was conducted in South Achefer district from October, 2015 to April, 2016. Faecal samples were collected from 360 randomly selected cattle for coprological examination of Schistosoma eggs using sedimentation technique. The geographical origin (kebele), signalment (breed, sex and age) and body condition of study animals were recorded as independent variables. RESULTS: Of the total of 360 faecal samples examined, 80 (22.2%) were found positive for Schistosoma bovis eggs. Prevalence of BS showed significant variability amongst study kebele's (p = 0.000) as well as between different breeds (p = 0.009), sexes (p = 0.030) and body condition groups (p = 0.000) of study animals. Compared to Gedema kebele, risk of Schistosomia bovis infection was significantly higher (p < 0.05) in Ahurie kebele (95% CI OR, 1.497-6.680) and lower in Kar kebele (95% CI OR, 0.069-0.507). Meanwhile, risk of BS was significantly higher in cattle with poor body condition (95% CI OR, 3.171-15.652) as compared to that exhibiting good body condition. Local breed (95% CI OR, 1.282-5.102) and female (95% CI OR, 1.018-3.634) cattle showed considerably higher risk of infection than crossbred and male cattle, respectively. CONCLUSION: Overall, agro-ecological, genotypic and sexual factors were important in determining prevalence of BS which had negative association with the nutritional status of cattle. Current and parallel prior observations underscore a need for careful consideration of the disease and its epidemiological drivers in genetic improvement programs and routine health management practices.

Parasitic Diseases that can Infect Travelers to Africa.

Travel is important in the spread of diseases, and the number of travelers is increasing daily. Therefore, the importance of the diseases that occur during or after travel is increasing. In underdeveloped countries in particular, parasitic diseases are epidemic or endemic, and these diseases lead to high numbers of deaths. People traveling from developed to underdeveloped countries have a higher risk of transmission of parasitic diseases during travel. Fifteen percent of the world's population lives in Africa. In terms of geography, economics, and development, the continent is divided into four regions: East Africa, South Africa, North Africa, and West Africa. In recent years, international travels to Africa have been increasing. During these travels, there is a risk of contracting parasitic diseases, such as malaria, schistosomiasis, trypanosomiasis (African sleeping disease), onchocerciasis, lymphatic filariasis, and leishmaniasis. Before traveling to Africa, it is vital to take measures against diseases in the region.

Up-regulation of Interleukin-21 Contributes to Liver Pathology of Schistosomiasis by Driving GC Immune Responses and Activating HSCs in Mice.

The pathology of schistosome egg-induced liver granuloma, fibrosis and eventually liver scarring is complicated. CD4+ helper T (Th) cells play critical roles in both host humoral immunity and cellular immunity against parasitic infection and immunopathology in schistosomiasis. Follicular helper T (Tfh) cells are another specialized subset of Th cells and involved in infectious diseases. However, the immune regulatory mechanism of Tfh cells in severe liver pathology of schistosomiasis is still poorly understood. In this study, using a S. japonicum-infected mouse model, we studied the dynamics and effects of Tfh cells in vivo and demonstrated that Tfh phenotype molecules ICOS, PD-1 and functional factor IL-21 were positively correlated with disease development by flow cytometry. Meanwhile, our results also showed that Tfh cells enriched in splenic germinal center (GC) and promoted B cells producing IgM with the progress of hepatic immunopathology by B-T co-culture experiments. More importantly, our data indicated that IL-21 contributed to the formation and development of hepatic egg granuloma and subsequent fibrosis by driving GC responses and activating HSCs by immunohistochemical detection and blocking assay in vitro. Our findings contribute to the better understanding of the immunopathogenesis of schistosomiasis and have implications for therapeutic intervention of hepatic fibrotic diseases.

Observer design for a schistosomiasis model.

This paper deals with the state estimation for a schistosomiasis infection dynamical model described by a continuous nonlinear system when only the infected human population is measured. The central idea is studied following two major angles. On the one hand, when all the parameters of the model are supposed to be well known, we construct a simple observer and a high-gain Luenberger observer based on a canonical controller form and conceived for the nonlinear dynamics where it is implemented. On the other hand, when the nonlinear uncertain continuous-time system is in a bounded-error context, we introduce a method for designing a guaranteed interval observer. Numerical simulations are included in order to test the behavior and the performance of the given observers.

The relative contribution of immigration or local increase for persistence of urban schistosomiasis in Salvador, Bahia, Brazil.

Urbanization is increasing across the globe, and diseases once considered rural can now be found in urban areas due to the migration of populations from rural endemic areas, local transmission within the city, or a combination of factors. We investigated the epidemiologic characteristics of urban immigrants and natives living in a neighborhood of Salvador, Brazil where there is a focus of transmission of Schistosoma mansoni. In a cross-sectional study, all inhabitants from 3 sections of the community were interviewed and examined. In order to determine the degree of parasite differentiation between immigrants and the native born, S. mansoni eggs from stools were genotyped for 15 microsatellite markers. The area received migrants from all over the state, but most infected children had never been outside of the city, and infected snails were present at water contact sites. Other epidemiologic features suggested immigration contributed little to the presence of infection. The intensity and prevalence of infection were the same for immigrants and natives when adjusted for age, and length of immigrant residence in the community was positively associated with prevalence of infection. The population structure of the parasites also supported that the contribution from immigration was small, since the host-to-host differentiation was no greater in the urban parasite population than a rural population with little distant immigration, and there had been little differentiation in the urban population over the past 7 years. Public health efforts should focus on eliminating local transmission, and once eliminated, reintroduction from distant migration is unlikely.

Recombinant adeno-associated virus-mediated inhibition of microRNA-21 protects mice against the lethal schistosome infection by repressing both IL-13 and transforming growth factor beta 1 pathways.

UNLABELLED: Schistosomiasis is a serious parasitic disease in humans, which can lead to liver fibrosis and death. Accumulating evidence indicated that targeting the deregulated microRNAs (miRNAs) could mitigate disease outcomes. Here, we showed that progressive hepatic schistosomiasis caused elevation of miR-21 and efficient and sustained inhibition of miR-21 by using highly hepatic tropic adeno-associated virus serotype 8 (rAAV8), which protected mice against lethal schistosome infection through attenuation of hepatic fibrosis (HF). We demonstrated an additive role of interleukin (IL)-13 and transforming growth factor beta 1 (TGF-ß1) in up-regulating miR-21 expression in hepatic stellate cells (HSCs) by activation of mothers against decapentaplegic (SMAD) proteins. Furthermore, down-regulation of miR-21 in HSCs reversed HF by enhancing SMAD7 expression, thus repressing TGF-ß1/Smad and IL-13/Smad pathways. CONCLUSION: This study suggests the mechanism of IL-13-mediated schistosomiasis HF by up-regulation of miR-21 and highlights the potential of rAAV8-mediated miR-21 inhibition as a therapeutic intervention for hepatic fibrotic diseases, such as schistosomiasis.

Schistosomiasis combined with colorectal carcinoma diagnosed based on endoscopic findings and clinicopathological characteristics: a report on 32 cases.

AIMS AND BACKGROUND: To improve understanding of the relationship between schistosome-related enteropathy and colorectal carcinoma with particular focus on endoscopic findings and clinicopathological characteristics of colonic schistosomiasis. MATERIALS AND METHODS: All cases of intestinal schistosomiasis diagnosed at West China Hospital, Chengdu, China, between October 2006 and October 2012 were included in this study. A total of 179 cases of colonic schistosomiasis diagnosed through colonoscopy and pathological examinations were collected for analysis and the demographics, symptoms, endoscopic findings and clinicopathological characteristics were retrospectively evaluated. RESULTS: Of the 179 colonic schistosomiasis patients, 32 combined with colorectal cancer (CRC) were found, between the ages of 44 and 85 years (24 males, 75%). These 32 lesions were classified as 12 endophytic/ulcerative (37.5%), 10 exophytic/fungating (31.2%), 4 annular (12.5%), 3 giant polypus (9.4%), and 3 IIc (superficial depressed type) (9.4%). The segments of rectum and sigmoid colon were involved in 19 patients (59.4%) and 6 patients (18.8%), respectively. The histopathologic types were classified as follows: 30 well- differentiated adenocarcinomas, one mucinous adenocarcinoma and one poorly differentiated adenocarcinoma. The pathological findings suggest colorectal malignancy with deposited schistosome ova. CONCLUSIONS: Chronic schistosomal infestation has a probable etiological role in promoting genesis of colorectal neoplasms.

Epidemiology of schistosomiasis in two high-risk communities of south Cote d'Ivoire with particular emphasis on pre-school-aged children.

Schistosomiasis control efforts mainly target school-aged children. We studied the epidemiology of schistosomiasis in two high-risk communities in south Côte d'Ivoire, placing particular emphasis on pre-school-aged children. We used a suite of diagnostic techniques, including Kato-Katz, urine filtration, reagent strips, and urine circulating cathodic antigen cassettes. Risk factors for schistosomiasis were determined by focus group discussions and a structured questionnaire. The prevalence of Schistosoma mansoni in the two study villages among the pre-school-aged children (age < 6 years) was 20.9% and 25.0%, whereas several-fold higher prevalences were found in school-aged children (58.7-68.4%) and adolescents/adults (59.5-61.7%). The prevalence of S. haematobium in the three age groups was 5.9-17.3%, 10.9-18.4%, and 3.8-21.3%, respectively. Most participants had light-intensity infections. Mothers' occupations and older siblings play important roles in the epidemiology of schistosomiasis in pre-schoolers. In the current epidemiologic settings, more attention is warranted on pre-school-aged children and adolescents/adults for successful schistosomiasis control.

[Progress in researches of molecular mechanism of schistosome cercariae infection].

Schistosome cercariae must penetrate skin as an initial step to successfully infect the final host. Proteolytic enzymes secreted from the acetabular glands of cercariae contribute significantly to the invasion process. Nowadays, the researches of molecular mechanism of schistosome infection mainly focus on the cercarial secretions including serine protease and cysteine protease. Previous researches already showed that Schistosoma mansoni penetrates the skin mainly depend on cercarial elastease secreted by cercariae while Schistosoma japonicum penetrates the skin chiefly by cathepsin B2. The illustration of molecular mechanism of schistosome cecariae infection will accelerate the identification of novel vaccines and drug targets.

[River beach contamination index in monitoring of schistosomiasis].

Diseased animals are the main source of infection of schistosomiasis. River beach wild fecal contamination is the direct risk factor for schistosomiasis transmission, and the river beach contamination index has important significance in the schistosomiasis monitoring. This paper reviews the river beach wild fecal contamination to the identification and evaluation of the risk of schistosomiasis transmission.

Esquistosomiasis como causa de hematuria macroscópica / Schistosomiasis as a cause of gross hematuria

La esquistosomiasis (o bilarzhiasis) es una enfermedad parasitaria muy extendida en el mundo, que deberemos considerar en el diagnóstico diferencial de diversas entidades, predominantemente la hematuria, ante población inmigrante procedente de áreas endémicas. Presentamos el caso de un varón de 11 años original de Gambia con hematuria macroscópica de larga evolución por esquistosomiasis vesical. El estudio microbiológico de orina demostró huevos de Schistosoma haematobium(AU)

Bilarzhia is one of the most prevalent parasitic diseases in the world, that we should consider in the differential diagnosis of different entities, such as hematuria, most of it occurs in immigrant population coming from endemic areas. We present a case report of a child eleven years old original from Gambia, with gross hematuria due to vesical esquistosomiasis. The urinary microbiology study showed Schistosoma haematobium eggs(AU)

[Automatic microscopic scanning system in etiological diagnosis of schistosomiasis].

OBJECTIVE: To apply the automatically microscopic scanning system in the etiological diagnosis of schistosomiasis, as an alternative to the traditional manual microscopy detection, and improve the detection rates and efficiency of examinations of fecal slides. METHODS: A single-blind method was used throughout the process of both the automatic microscopic scanning system and traditional manual microscopy reading. Each of five professionals read 20 Kato-Katz manure piece samples. The detection results and time for each sample were recorded. The two methods were compared by the film reading speed, sensitivity, specificity, and accuracy. RESULTS: The overall accuracy of the diagnosis of schistosomiasis of the automatically microscopic scanning image system was 99.00%, higher than that of the traditional manual microscopy detection (91.00%) (P < 0.05); the sensitivity and specificity of the image system were 98.57% and 100%, respectively, and also higher than those of the traditional manual microscopy method (90.00% and 93.33%) (all P < 0.05). CONCLUSIONS: The automatically microscopic scanning system is powerful, the scanning speed is fast, and the operation is easy. Its speed, accuracy, sensitivity and specificity are superior to those of the conventional manual microscopy; therefore, it is suitable for the etiological diagnosis of schistosomiasis at the grassroots' level.

Cerebral Schistosomiasis: case report and review of literature

Schistosomiasis is an infection caused by trematodes (flatworms from the phylum Platyhelminthes), which are acquired transcutaneously by swimming in contaminated waters. The central nervous system (CNS) schistosomiasis is a rare presentation of the disease. Brain infection to S. Mansoni has been rarely reported, in anedoctal fashion. It should be recognized early, since it disposes a specific treatment, and this treatment may prevent neurological deterioration. A high index of suspicion is necessary, mainly in patients coming from endemic areas, with brain or spinal cord lesions associated with eosinophilia and inflammatory CSF. Finding eggs from schistosoma into excrements or CNS biopsy confirms the diagnosis. We describe a 35-year old Brazilian man, harboring an isolated brain infection to S. mansoni.

Schistosomiasis among recreational users of Upper Nile River, Uganda, 2007.

After recreational exposure to river water in Uganda, 12 (17%) of 69 persons had evidence of schistosome infection. Eighteen percent self-medicated with praziquantel prophylaxis immediately after exposure, which was not appropriate. Travelers to schistosomiasis-endemic areas should consult a travel medicine physician.