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Sample records for schistosomiasis mansoni

  1. Interventions for treating schistosomiasis mansoni.

    Science.gov (United States)

    Saconato, H; Atallah, A

    2000-01-01

    Schistosomiasis is a parasite that is carried by freshwater snails. The intestinal form infects the intestine, liver and spleen and can be fatal. The objective of this review was to assess the effects of oxamniquine or praziquantel for treating Schistosomiasis mansoni We searched the Cochrane Infectious Diseases Group trials register, the Cochrane Controlled Trials Register, Medline, Lilacs and reference lists of articles. The Revista da Sociedade Brasileira de Medicina Tropical and Brazilian Tropical Medicine Congress abstracts were handsearched Randomised and quasi-randomised trials comparing oxamniquine and/or praziquantel to placebo for the treatment of Schistosomiasis mansoni. Two reviewers independently assessed trial quality and extracted data. Thirteen trials met the inclusion criteria. Praziquantel and oxamniquine were effective in curing Schistosoma mansoni infection when compared to placebo. In Africa, praziquantel 40 mg/Kg is more effective than oxamniquine 15 mg/Kg in individuals older than 14 years (OR 3.54, 95%CI 1.70, 7.38), but no difference was found when compared with oxamniquine 30 mg/Kg (OR 0.29, 95%CI 0.08, 1.01). In Brazil, praziquantel was equally effective when compared with oxamniquine in individuals older than 14 years (OR 1.70, 95%CI 0.83, 3.49). Both drugs appear safe. There was no difference in reinfection rate between zinc supplementation and placebo (OR 0.82, 95%CI 0.47, 1.41). IPraziquantel and oxamniquine both appear to be effective for the treatment of Schistosomiasis mansoni, although lower doses of oxamniquine (less than 30 milligrams per kilogram) may not be as effective.

  2. Schistosomiasis mansoni in Yemen: A review.

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    Sallam, J A; Wright, S G

    1992-05-01

    Schistosomiasis is a major public health problem in Yemen. In 1922 Schistosomiasis mansoni was first reported to be found in Yemeni patients. In 1951 the first population survey was carried out in Taiz and revealed the presence of Biomphalaria biossyi arabica where 35% of the snails were heavily infected with S. mansoni and in San'a no snails were infected. Although S. mansoni and S. hematobium infections have been found in most parts of Yemen Arab Republic (YAR) it seems that the disease is not a public health problem in some parts of the country such as Hodeidah, Al-Beidah, Mareb, and Al-Gouff. The source of S. mansoni and S. hematobium in Yemen was attributed to the continual migration of infected persons from Eritrea and other countries of East Africa to Yemen. The prevalence of infection is higher in rural than in urban areas. The complications of S. mansoni, notably portal hypertension, esophageal varices, and hematemesis have become a major clinical problem. The availability of Praziquantel as a safe and effective treatment makes case findings and treatment an important part of schistosomiasis control. Control of the disease also requires field studies followed by mollusciding, improvement of water supply and sanitation and, perhaps most importantly, health education.

  3. Schistosomiasis mansoni and soil-transmitted helminthiasis in ...

    African Journals Online (AJOL)

    Results: The overall infection rates of schistosomiasis mansoni, trichuriasis, ascariasis and hookworm infection were 73.7%, 41.5%, 37.2% and 28.4%, respectively. Other parasitic infections observed were caused by Hymenolepis nana (1.7%), Taenia species (1.4%), and Enterobius vermicularis (1.4%). Children in the age ...

  4. Schistosomiasis mansoni in school attenders and non-attenders in ...

    African Journals Online (AJOL)

    Background: Information on epidemiology of schistosomiasis in school age children and particularly non school attenders are scanty in northwestern Ethiopia. Objective: To assess the prevalence of Schistosoma mansoni in school attenders and non-attenders in Northwest Ethiopia. Methods: A parasitological survey was ...

  5. Schistosomiasis mansoni and soil-transmitted helminthiasis in ...

    African Journals Online (AJOL)

    Background: Schistosomiasis mansoni and soil-transmitted helminthiasis (STHs) are considerable medical and public health problems in Ethiopia. However, information is limited on the epidemiology of these infections in different localities even though it is needed to plan effective prevention and control measures.

  6. Decline in transmission of schistosomiasis mansoni in Oman.

    Science.gov (United States)

    Al Abaidani, Idris; Al-Abri, Seif; Shaban, Mahmoud; Ghugey, Satish L; Al Kathery, Salem; Al-Mashikhi, Khalid; Garba, Amadou; Gabrielli, Albis Francesco

    2016-12-12

    Intestinal schistosomiasis due to Schistosoma mansoni was first reported in Oman in 1979. We describe the trend in parasitological and serological prevalence of human infection with S. mansoni in the endemic area over the period 1982-2014, and the compliance of data generated by the national monitoring and evaluation system with schistosomiasis elimination criteria set by the Ministry of Health of Oman. Parasitological and serological assessments were carried out on population (mainly children) living in the area at risk for schistosomiasis in Dhofar, the country's only endemic Governorate, for a period of over 30 years. Kato-Katz thick smear and Indirect Haemagglutination Assay were the techniques employed. Data indicate a progressive decline in prevalence of S. mansoni throughout the 1980s and the 1990s, a recrudescence in the early 2000s, and a more marked decrease following the implementation of six rounds of mass treatment with praziquantel from 2007 to 2013. Latest parasitological prevalence (2011) was 0%, while latest serological prevalence (2014) was 0.11%. Transmission of schistosomiasis has reached very low levels in Oman. Elimination criteria established by the Ministry of Health of Oman (parasitological prevalence ≤ 1% and serological prevalence ≤ 5%) have been met since 2008. Further investigations are required to assess whether interruption of transmission has been achieved in some or all foci, in view of the establishment of a formal verification process under the auspices of WHO.

  7. Association between Schistosomiasis mansoni and hepatitis C: systematic review

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    Daniele Silva de Moraes Van-Lume

    2013-06-01

    Full Text Available OBJECTIVE: To perform a systematic review of the prevalence of the HCV/ S. mansoni co-infection and associated factors in Schistosoma mansoni -infected populations. METHODS: The bibliographic search was carried out using the Medline, Lilacs, SciELO, Cochrane Library and Ibecs databases. The criteria for the studies' selection and the extraction data were based on systematic review methods. Forty five studies were found, with nine being excluded in a first screening. Thirteen articles were used for data extraction. RESULTS: The HCV infection rates in schistosomiasis populations range from 1% in Ethiopia to 50% in Egypt. Several studies had poorly defined methodologies, even in areas characterized by an association between hepatitis C and schistosomiasis, such as Brazil and Egypt, which meant conclusions were inconsistent. HCV infection rates in schistosomotic populations were heterogeneous and risk factors for acquiring the virus varied widely. CONCLUSIONS: Despite the limitations, this review may help to identify regions with higher rates of hepatitis C and schistosomiasis association. However, more studies are necessary for the development of public health policies on prevention and control of both diseases.

  8. Extramedullary hematopoiesis in murine schistosomiasis mansoni

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    H. L. Lenzi

    1995-04-01

    Full Text Available During Schistosoma mansoni infection, there is morphological evidence of involvement of various hematopoietic growth factors, which cause eosinophil, neutrophil, megakaryocytic and erythroid extramedullary foci in the liver, lymph nodes and omental and mesenteric milky spots. While the eosinophil metaplasia in the periphery of hepatic granulomas roughly reproduced the intensity of the medullary eosinopoiesis, the neutrophil metaplasia, on the contrary, was more intense during the period of neutrophil depression in the bone marrow. This fact suggests that extramedullary hematopoietic foci are locally regulated, and amplify and/or compensate the systemic hematopoietic response during the infection.

  9. Oxamniquine, praziquantel and lovastatin association in the experimental Schistosomiasis mansoni

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    Neusa Araújo

    2008-08-01

    Full Text Available The activity of lovastatin associated with oxamniquine or praziquantel against schistosomiasis mansoni was evaluated in mice infected with Schistosoma mansoni. Forty days after infection, mice were treated with lovastatin, 400 mg/kg for five consecutive days by oral route, and on the last day of this sequence with 50 mg/kg oxamniquine or with 200 mg/kg praziquantel, both by oral route, single dose. Fifteen days later, the animals were perfused in parallel with an untreated control group. Studies were carried out in vitro, using lovastatin in culture medium containing S. mansoni worms proceeding from experimentally infected mice. In the in vivo trials, the association of lovastatin with oxamniquine or praziquantel did not show any additive action, but there were oogram changes when lovastatin was associated with oxamniquine. In vitro lovastatin was able to interrupt the maturation of S. mansoni eggs, which remained at the 1st or 2nd stages, depending on the dose used. The total number of morphologically dead eggs found in culture of worms exposed to 2 µg/ml or 4 µg/ml concentrations of lovastatin was significantly higher than the number of viable eggs. Using the probe Hoescht 33258 it was observed that 70% of the eggs considered morphologically viable in the treated groups (against 16% in the control group were labeled, indicating that the majority of the viable eggs had membrane permeability increased due to lovastatin action.

  10. Genital manifestations of schistosomiasis mansoni in women: important but neglected

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    Hermann Feldmeier

    1998-01-01

    Full Text Available Egg-induced lesions in the upper and the lower female reproductive tract are important complications of the infection with Schistosoma mansoni. The understanding of the pathophysiology and pathology of genital lesions is only rudimentary, simple and reliable diagnostic tools are not at hand, epidemiological data do not exist and how to treat best the women affected, is not known. In view of recent advances in the understanding of genital lesions induced by S. haematobium the existing literature is critically analysized and possible consequences of female genital schistosomiasis are outlined. We estimate that 6 to 27 % girls and women with intestinal schistosomiasis, at least temporarily, suffer from pathology induced by eggs sequestered somewhere in their genital organs. This is a mattern of concern and warrants more research into the epidemiology, pathology, diagnosis and therapy of this disease entity.

  11. Splenectomy Improves Hemostatic and Liver Functions in Hepatosplenic Schistosomiasis Mansoni.

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    Luiz Arthur Calheiros Leite

    Full Text Available Schistosomiasis mansoni is a chronic liver disease, in which some patients (5-10% progress to the most severe form, hepatosplenic schistosomiasis. This form is associated with portal hypertension and splenomegaly, and often episodes of gastrointestinal bleeding, even with liver function preserved. Splenectomy is a validated procedure to reduce portal hypertension following digestive bleeding. Here, we evaluate beneficial effects of splenectomy on blood coagulation factors and liver function tests in hepatosplenic schistosomiasis mansoni compared to non-operated patients.Forty-five patients who had undergone splenectomy surgery were assessed by laboratory analyses and ultrasound examination and compared to a non-operated group (n = 55. Blood samples were obtained for liver function tests, platelet count and prothrombin time. Coagulation factors (II, VII, VIII, IX and X, protein C and antithrombin IIa, plasminogen activator inhibitor-1 were measured by routine photometric, chromogenic or enzyme-linked immunosorbent assays, while hyperfibrinolysis was defined by plasminogen activator inhibitor-1 levels. Both groups had similar age, gender and pattern of periportal fibrosis. Splenectomized patients showed significant reductions in portal vein diameter, alkaline phosphatase and bilirubin levels compared to non-operated patients, while for coagulation factors there were significant improvement in prothrombin, partial thromboplastin times and higher levels of factor VII, VIII, IX, X, protein C and plasminogen activator inhibitor-1.This study shows that the decrease of flow pressure in portal circulation after splenectomy restores the capacity of hepatocyte synthesis, especially on the factor VII and protein C levels, and these findings suggest that portal hypertension in patients with hepatosplenic schistosomiasis influences liver functioning and the blood coagulation status.

  12. Acute schistosomiasis mansoni: revisited and reconsidered

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    José Roberto Lambertucci

    2010-07-01

    Full Text Available Acute schistosomiasis is a systemic hypersensitivity reaction against the migrating schistosomula and eggs. A variety of clinical manifestations appear during the migration of schistosomes in humans: cercarial dermatitis, fever, pneumonia, diarrhoea, hepatomegaly, splenomegaly, skin lesions, liver abscesses, brain tumours and myeloradiculopathy. Hypereosinophilia is common and aids diagnosis. The disease has been overlooked, misdiagnosed, underestimated and underreported in endemic areas, but risk groups are well known, including military recruits, some religious congregations, rural tourists and people practicing recreational water sports. Serology may help in diagnosis, but the finding of necrotic-exudative granulomata in a liver biopsy specimen is pathognomonic. Differentials include malaria, tuberculosis, typhoid fever, kala-azar, prolonged Salmonella bacteraemia, lymphoma, toxocariasis, liver abscesses and fever of undetermined origin. For symptomatic hospitalised patients, treatment with steroids and schistosomicides is recommended. Treatment is curative in those timely diagnosed.

  13. Intestinal schistosomiasis caused by both Schistosoma intercalatum and Schistosoma mansoni.

    Science.gov (United States)

    Tzanetou, Konstantina; Astriti, Myrto; Delis, Vassilios; Moustakas, George; Choreftaki, Theodosia; Papaliodi, Eugenia; Sarri, Katerina; Adamis, George

    2010-05-01

    A case is presented of intestinal schistosomiasis due to both Schistosoma intercalatum and Schistosoma mansoni in a 30-year-old man from Senegal with discussion of diagnostic approach, species identification and determination of the effect of treatment. The patient was admitted to hospital for investigation of renal failure, arterial hypertension and hypereosinophilia. Repeated stool examinations for ova and parasites were negative. Ultrasonography (US) and computed tomography (CT) of the abdomen showed no abnormalities. US of the urinary tract showed kidneys of borderline size with increased echogenicity. Cystoscopy and histopathological examination of bladder biopsy specimens were normal. Flexible colonoscopy revealed numerous nodular lesions in the rectosigmoid region and a few similar lesions in the transverse colon, the histopathological examination of which showed deposition of Schistosoma ova with granuloma formation. Examination of multiple crush biopsy specimens from the rectosigmoid region revealed numerous granulomas formed around Schistosoma eggs which had a terminal spine and were identified as S. intercalatum (longer than Schistosoma haematobium and with a slightly curved terminal spine) and a very few S. mansoni eggs. Crush biopsies from the lesions in the transverse colon showed only S. mansoni eggs. In conclusion, the examination of multiple crush biopsy specimens is a very sensitive and specific technique for species identification of Schistosoma, especially in mixed infections, and for defining the location and extent of the granulomas evoked by each species. Copyright 2010 Elsevier Ltd. All rights reserved.

  14. Serological studies on schistosomiasis mansoni in the northeast Brazil (I).

    Science.gov (United States)

    Tanabe, M; Okazaki, M; Okazaki, M; Kobayashi, S; Kaneko, N; Sekiguchi, T; Tateno, S; Motta, S R; Takeuchi, T

    1990-01-01

    Sera from the patients (N = 10) with schistosomiasis mansoni of the hospital of Federal University of Pernambuco, the Schistosoma mansoni egg-positive (N = 51) and -negative (N = 452) inhabitants in Cabo City area, out-patients (N = 37) of the IMIP hospital and Japanese immigrants (N = 127) in Petrolina City area of northeast Brazil as well as Japanese healthy subjects (N = 30) were examined by serological tests including an enzyme-linked immunosorbent assay with antigens prepared from eggs (ELISA-egg) and adult worms (ELISA-adult). The ELISA with egg or adult antigen correctly identified 100% of the uninfected individuals lived in non-endemic area of schistosomiasis. Moreover, when examined cross-reactivity of our ELISA with sera isolated from 78 subjects infected with various intestinal parasitic infections, only one of these sera reacted with the egg and adult antigens. On the examination of 51 sera from the egg-positive subjects, the ELISA-egg revealed the highest sensitivity (98.0%), whereas a large number of false negative reactions of ELISA-adult, Ouchterlony method using adult antigen, circumoval precipitation and immediate intradermal skin test were observed. A low sensitivity of these serologic tests except for ELISA-egg appears to be primarily due to their inability to detect antibody in the sera from egg-positive infantiles. There was no positive correlation between the absorbance values of these two types of ELISA among the sera isolated from ELISA-positive subjects. Rather, by the reactivity of these sera to egg or adult antigen, they could be divided into two subgroups; one reacted more positively with egg antigen and the other with adult antigen. Moreover, it was confirmed that the sera from young subjects (under 20 years old) appear to be highly reactive to the egg antigen than did aged ones. These data suggest that the ELISA with egg antigen, but not with the adult antigen, appears to be useful for the serological survey of schistosomiasis mansoni

  15. Identification of Schistosoma mansoni candidate antigens for diagnosis of schistosomiasis

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    Gardenia Braz Figueiredo Carvalho

    2011-11-01

    Full Text Available The development of a more sensitive diagnostic test for schistosomiasis is needed to overcome the limitations of the use of stool examination in low endemic areas. Using parasite antigens in enzyme linked immunosorbent assay is a promising strategy, however a more rational selection of parasite antigens is necessary. In this study we performed in silico analysis of the Schistosoma mansoni genome, using SchistoDB database and bioinformatic tools for screening immunogenic antigens. Based on evidence of expression in all parasite life stage within the definitive host, extracellular or plasmatic membrane localization, low similarity to human and other helminthic proteins and presence of predicted B cell epitopes, six candidates were selected: a glycosylphosphatidylinositol-anchored 200 kDa protein, two putative cytochrome oxidase subunits, two expressed proteins and one hypothetical protein. The recognition in unidimensional and bidimensional Western blot of protein with similar molecular weight and isoelectric point to the selected antigens by sera from S. mansoni infected mice indicate a good correlation between these two approaches in selecting immunogenic proteins.

  16. Schistosomiasis mansoni: novel chemotherapy using a cysteine protease inhibitor.

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    Maha-Hamadien Abdulla

    2007-01-01

    Full Text Available Schistosomiasis is a chronic, debilitating parasitic disease infecting more than 200 million people and is second only to malaria in terms of public health importance. Due to the lack of a vaccine, patient therapy is heavily reliant on chemotherapy with praziquantel as the World Health Organization-recommended drug, but concerns over drug resistance encourage the search for new drug leads.The efficacy of the vinyl sulfone cysteine protease inhibitor K11777 was tested in the murine model of schistosomiasis mansoni. Disease parameters measured were worm and egg burdens, and organ pathology including hepato- and splenomegaly, presence of parasite egg-induced granulomas in the liver, and levels of circulating alanine aminotransferase activity as a marker of hepatocellular function. K11777 (25 mg/kg twice daily [BID], administered intraperitoneally at the time of parasite migration through the skin and lungs (days 1-14 postinfection [p.i.], resulted in parasitologic cure (elimination of parasite eggs in five of seven cases and a resolution of other disease parameters. K11777 (50 mg/kg BID, administered at the commencement of egg-laying by mature parasites (days 30-37 p.i., reduced worm and egg burdens, and ameliorated organ pathology. Using protease class-specific substrates and active-site labeling, one molecular target of K11777 was identified as the gut-associated cathepsin B1 cysteine protease, although other cysteine protease targets are not excluded. In rodents, dogs, and primates, K11777 is nonmutagenic with satisfactory safety and pharmacokinetic profiles.The significant reduction in parasite burden and pathology by this vinyl sulfone cysteine protease inhibitor validates schistosome cysteine proteases as drug targets and offers the potential of a new direction for chemotherapy of human schistosomiasis.

  17. Human schistosomiasis mansoni: studies on in vitro granuloma modulation

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    Juçara C. Parra

    1992-01-01

    Full Text Available Infection with Schistosoma mansoni induces humoral and T cell mediated responses and leads to delayed hipersensitivity that results in granulomatous inflamatory disease around the parasite eggs. Regulation of these responses resulting in a reduction in this anti-egg inflamatory disease is appsrently determined by idiotypic repertoires of the patient, associated with genetic background and multiple external factors. We have previously reported on idiotype/anti-idiotype-receptor transactions in clinical human schistosomiasis. These findings support a hypothesis that anti-SEA cross-reactive idiotypes develop in some patients during the course of a chronic infection and participate in regulation of anti-SEA cellular immune responses. We repport here on experiments wich extend those observations to the regulation of granulomatous hypersensitivity measured by an in vitro granuloma model. T cells from chronic intestinal schistosomiasis patients were stimulated in vitro with anti-SEA idiotypes and assayed in an autologous in vitro granuloma assay for modulation of granuloma formation. These anti-SEA idiotype reactive T cells were capable of regulating autologous in vitro granuloma formation. This regulatory activity, initiated with stimulatory anti-SEA idiotypic antibodies, was antigenically specific and was dependent on the present of intact (F(ab'2 immunoglobulin molecules. The ability to elicit this regulatory activity appears to be dose dependent and is more easily demonstrated in chronically infected intestinal patients or SEA sensitized individuals. These data support the hypothesis that anti-SEA cross reactive idiotypes are important in regulating granulomatous hypersensitivy in chronic intestinal schistosomiasis patients and these cross-reactive idiotypes appear to play a major role in cell-cell interactions which result in the regulation of anti-SEA cellular immune responses.

  18. Magnetic resonance imaging of cerebellar Schistosomiasis mansoni; Ressonancia magnetica na esquistossomose mansoni cerebelar

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    Braga, Bruno Perocco; Costa Junior, Leodante Batista da [Hospital da Baleia, Belo Horizonte, MG (BRazil). Servico de Neurocirurgia; Lambertucci, Jose Roberto [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Faculdade de Medicina. Servico de Doencas Infecciosas e Parasitarias

    2003-10-01

    A 15-year-old boy was admitted to hospital with a history of headache, dizziness, vomiting and double vision that started two weeks before. His parents denied any previous disease. During clinical examination he presented diplopia on lateral gaze to the left and horizontal nystagmus. No major neurological dysfunction was detected. He was well built, mentally responsive and perceptive. Laboratory findings revealed a leukocyte count of 10,000/mL, a normal red blood cell count and no eosinophilia. The magnetic resonance images (MRI) of the brain showed a left cerebellar lesion with mass effect compressing the surrounding tissues. Contrast-enhanced images showed a mass like structure and punctate nodules (Figures A and B: axial and coronal contrast-enhanced T1-weighted MR images showed the nodular - yellow arrows - enhancement pattern of a left cerebellar intraxial lesion). The lesion extended to the vermis and brachium pons and compressed the medulla. There was no hydrocephalus. He was taken to the operating room with the presumptive diagnosis of a neuroglial tumor, and submitted to a lateral suboccipital craniectomy. A brown, brittle tumoral mass without a clearly defined margin with the cerebellar tissue was removed. Microscopic examination revealed schistosomal granulomas in the productive phase in the cerebellum (Figure C). After surgery, treatment with praziquantel (50 mg/kg/dia, single dose) and prednisone (1 mg/kg/day) was offered and the patient improved quickly. Thirty days later he was seen again at the outpatient clinic: he was asymptomatic and with no neurological impairment. This is the eighth case of cerebellar involvement in schistosomiasis mansoni and the second report of a tumoral form of cerebellar schistosomiasis documented by magnetic resonance images. (author)

  19. Forma aguda ou toxêmica da esquistossomose mansoni Acute or toxemic form of mansoni's schistosomiasis

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    Jayme Neves

    1992-01-01

    Full Text Available The acute toxemic form of schistosomiasis mansoni is studied under anatomic and clinical point of view, according to classification made by Neves, Raso and Bagliolo in 1975. The first phase is characterized by the following facts: cutaneous (immediate and late manifestations; high fever or in progressive elevation; intense diaphoresis abdominal disconfort; intense acquous diarrhea; dehidratation; loss of weight, dry cough; painful hepatosplenomegaly; discreet lymphademegaly, progressive increase of blood leucocytes and eosinophisles; radiological pulmonary alterations; absence of alterations in serum protein and hepatic functional tests; the hepatic function byopsy shows focus of acute hepatitis. The second stage or properly named toxemic period was clinically characterized by the neat aggravation of the previously observed phenomena. At last, the evolutive course of the disease has implication derived not only of the worm's presence, but from the intense dissemination of eggs in the tissue. In the pre-laying phase one studied the forms of cercarian dermatitis, prodromic and innapparent. In the post laying phase, the properly named acute toxemic form, with its types: pseudocholeraic, pseudotyphous, pseudodysenteric-bacillary, pseudonophritic, pseudoenterovirotic, the reactivated, the ischemic enterocolitis and others; whenever possible clinical and anatomic correlation will be made.

  20. A spectral analysis of the myoelectric activity of the left colon in patients with schistosomiasis mansoni

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    A.A.B. Ferraz

    2005-05-01

    Full Text Available The objective of the present study was to perform a spectral analysis of the electrical activity of the left colon of patients with hepatosplenic schistosomiasis. Thirty patients were studied, divided into 2 groups: group A was composed of 14 patients (9 males and 5 females with hepatosplenic schistosomiasis and group B was composed of 16 female patients without schistosomiasis mansoni. Three pairs of electrodes were implanted in the left colon at the moment of the surgical treatment. The signals of the electric activity of the colon were captured after postoperative recovery from the ileus and fed into a computer by means of a DATAQ data collection system which identified and captured frequencies between 0.02 and 10 Hz. Data were recorded, stored and analyzed using the WINDAQ 200 software. For electrical analysis, the average voltage of the electrical wave in the three electrodes of all patients, expressed as millivolts (mV, was considered, together with the maximum and minimum values, the root mean square (RMS, the skewness, and the results of the fast Fourier transforms. The average RMS of the schistosomiasis mansoni patients was 284.007 mV. During a long period of contraction, the RMS increased in a statistically significant manner from 127.455 mV during a resting period to 748.959 mV in patients with schistosomiasis mansoni. We conclude that there were no statistically significant differences in RMS values between patients with schistosomiasis mansoni and patients without the disease during the rest period or during a long period of contraction.

  1. RE-EVALUATION OF SCHISTOSOMIASIS MANSONI IN MINAS GERAIS, BRAZIL. III. "NOROESTE DE MINAS" MESOREGION

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    CARVALHO Omar S.

    1998-01-01

    Full Text Available This study was conducted to assess the presence of schistosomiasis mansoni in the "Noroeste de Minas" mesoregion, an area considered non-endemic. A malacologic survey and parasitologic stool examinations were undertaken in 13 municipalities of the mesoregion. A sample of 3,283 primary school students was submitted to fecal examination by the Kato-Katz method. A total of 3,627 planorbids was collected and examined. The molluscs were identified as Biomphalaria straminea in seven municipalities (Unaí, Bonfinópolis de Minas, Paracatu, João Pinheiro, Vazante, Lagamar and Lagoa Grande and as Biomphalaria peregrina in one (Presidente Olegário. All planorbids were negative for Schistosoma mansoni. Four students were diagnosed with schistosomiasis in the municipalities of Buritis, Formoso, Paracatu and Unaí, but none of these cases was considered autochthonous. The data obtained indicate that the "Noroeste de Minas" mesoregion continues to be non-endemic for schistosomiasis mansoni, although the presence of intermediate hosts associated with parasitized individuals emphasizes the need for epidemiological surveillance of schistosomiasis in this mesoregion.

  2. Protective Effect of Chronic Schistosomiasis in Baboons Coinfected with Schistosoma mansoni and Plasmodium knowlesi

    DEFF Research Database (Denmark)

    Nyakundi, Ruth K; Nyamongo, Onkoba; Maamun, Jeneby

    2016-01-01

    models. To examine this interaction, we conducted a randomized controlled study using the baboon (Papio anubis) to analyze the effect of chronic schistosomiasis on severe malaria. Two groups of baboons (n = 8 each) and a schistosomiasis control group (n = 3) were infected with 500 Schistosoma mansoni...... malaria. A total of 81% of baboons exposed to chronic S. mansoni infection with or without praziquantel treatment survived malaria, compared to only 25% of animals infected with P. knowlesi only (P = 0.01). Schistosome-infected animals also had significantly lower parasite burdens (P = 0.004) than...... the baboons in the P. knowlesi-only group and were protected from severe anemia. Coinfection was associated with increased spontaneous production of interleukin-6 (IL-6), suggesting an enhanced innate immune response, whereas animals infected with P. knowlesi alone failed to develop mitogen-driven tumor...

  3. [Critical analysis of the estimated number of Schistosomiasis mansoni carriers in Brazil].

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    Katz, N; Peixoto, S V

    2000-01-01

    The number of carriers of Schistosoma mansoni infection in Brazil was estimated based on the results of parasitological examinations of feces carried out by the Fundação Nacional de Saúde (FNS - National Health Foundation) in 1996 and 1997, as well as population data from 18 states collected by the Instituto Brasileiro de Geografia e Estatística (IBGE - Brazilian Institute of Geography and Statistics). This information allowed the number of carriers of schistosomiasis mansoni to be estimated at 7.1 million in 1996 and 6. 3 million in 1997. These figures may not reflect the true situation since the population sample used was not originally selected for this purpose. The absence of precise data indicates the need for an adequate national survey of the prevalence of schistosomiasis, which continues to be an important endemic parasitic disease, justifying greater efforts for its control in Brazil.

  4. Atypical presentation of cerebral schistosomiasis four years after exposure to Schistosoma mansoni

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    Matthew F. Rose

    2014-01-01

    Full Text Available Schistosomiasis is the second most socioeconomically devastating parasitic disease worldwide, affecting over 240 million people in 77 countries on 5 continents and killing 300,000 people annually in sub-Saharan Africa alone. Neuroschistosomiasis is caused by granuloma formation around eggs that lodge in the CNS, with Schistosoma mansoni and Schistosoma haematobium usually affecting the spinal cord and Schistosoma japonicum causing most reported cerebral disease. We report a case of a previously healthy 25-year-old woman native to the United States who presented with a single generalized tonic–clonic seizure without other neurologic symptoms four years after spending a semester in Ghana where she went swimming once in a river. Brain MRI showed areas of signal abnormality and mottled nodular linear enhancement in the left temporal and right posterior temporal/parietal lobes and right cerebellum without mass effect. A biopsy of the left temporal lesion showed prominent granulomas with dense mixed inflammatory infiltrates composed of eosinophils, plasma cells, and lymphocytes surrounding refractile egg shells containing characteristic embryonal cells and von Lichtenberg's envelope and displaying the pathognomonic spine shape of S. mansoni. Serum ELISA and antibody immunoblots confirmed exposure to S. mansoni. In summary, we describe the atypical combination of cerebral schistosomiasis due to S. mansoni, after a prolonged interval of four years, from a single known exposure.

  5. Schistosomiasis mansoni among school children of different water ...

    African Journals Online (AJOL)

    A total of eight species of helminth parasites were identified; the highest being Ascaris lumbricoides (10.45%) followed by Enterobius vermicularis (8.52%). The prevalence and intensity of S. mansoni infection showed the highest rate in the longstanding areas (13.73%), followed by the recently started irrigated areas from ...

  6. Soil-Transmitted Helminth Infections and Schistosomiasis mansoni ...

    African Journals Online (AJOL)

    Background: Schistosomes and geohelminths are highly prevalent causing serious health problem in the tropics. School children carry the heaviest burden of morbidity due to intestinal helminths and schistosomiasis infections. The aim of this study was to determine the prevalence and intensity of the major intestinal ...

  7. Soil-Transmitted Helminth Infections and Schistosomiasis mansoni ...

    African Journals Online (AJOL)

    user

    ABSTRACT. Background: Schistosomes and geohelminths are highly prevalent causing serious health problem in the tropics. School children carry the heaviest burden of morbidity due to intestinal helminths and schistosomiasis infections. The aim of this study was to determine the prevalence and intensity of the major.

  8. Phytol, a diterpene alcohol from chlorophyll, as a drug against neglected tropical disease Schistosomiasis mansoni.

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    Josué de Moraes

    Full Text Available BACKGROUND: Schistosomiasis is a major endemic disease that affects hundreds of millions worldwide. Since the treatment and control of this parasitic disease rely on a single drug, praziquantel, it is imperative that new effective drugs are developed. Here, we report that phytol, a diterpene alcohol from chlorophyll widely used as a food additive and in medicinal fields, possesses promising antischistosomal properties in vitro and in a mouse model of schistosomiasis mansoni. METHODS AND FINDINGS: In vitro, phytol reduced the motor activity of worms, caused their death and confocal laser scanning microscopy analysis showed extensive tegumental alterations in a concentration-dependent manner (50 to 100 µg/mL. Additionally, phytol at sublethal doses (25 µg/mL reduced the number of Schistosoma mansoni eggs. In vivo, a single dose of phytol (40 mg/kg administered orally to mice infected with adult S. mansoni resulted in total and female worm burden reductions of 51.2% and 70.3%, respectively. Moreover, phytol reduced the number of eggs in faeces (76.6% and the frequency of immature eggs (oogram pattern was significantly reduced. The oogram also showed increases in the proportion of dead eggs. Confocal microcopy studies revealed tegumental damage in adult S. mansoni recovered from mice, especially in female worms. CONCLUSIONS: The significant reduction in parasite burden by this chlorophyll molecule validates phytol as a promising drug and offers the potential of a new direction for chemotherapy of human schistosomiasis. Phytol is a common food additive and nonmutagenic, with satisfactory safety. Thus, phytol has potential as a safe and cost-effective addition to antischistosomal therapy.

  9. Phytol, a Diterpene Alcohol from Chlorophyll, as a Drug against Neglected Tropical Disease Schistosomiasis Mansoni

    Science.gov (United States)

    de Moraes, Josué; de Oliveira, Rosimeire N.; Costa, Jéssica P.; Junior, Antonio L. G.; de Sousa, Damião P.; Freitas, Rivelilson M.; Allegretti, Silmara M.; Pinto, Pedro L. S.

    2014-01-01

    Background Schistosomiasis is a major endemic disease that affects hundreds of millions worldwide. Since the treatment and control of this parasitic disease rely on a single drug, praziquantel, it is imperative that new effective drugs are developed. Here, we report that phytol, a diterpene alcohol from chlorophyll widely used as a food additive and in medicinal fields, possesses promising antischistosomal properties in vitro and in a mouse model of schistosomiasis mansoni. Methods and findings In vitro, phytol reduced the motor activity of worms, caused their death and confocal laser scanning microscopy analysis showed extensive tegumental alterations in a concentration-dependent manner (50 to 100 µg/mL). Additionally, phytol at sublethal doses (25 µg/mL) reduced the number of Schistosoma mansoni eggs. In vivo, a single dose of phytol (40 mg/kg) administered orally to mice infected with adult S. mansoni resulted in total and female worm burden reductions of 51.2% and 70.3%, respectively. Moreover, phytol reduced the number of eggs in faeces (76.6%) and the frequency of immature eggs (oogram pattern) was significantly reduced. The oogram also showed increases in the proportion of dead eggs. Confocal microcopy studies revealed tegumental damage in adult S. mansoni recovered from mice, especially in female worms. Conclusions The significant reduction in parasite burden by this chlorophyll molecule validates phytol as a promising drug and offers the potential of a new direction for chemotherapy of human schistosomiasis. Phytol is a common food additive and nonmutagenic, with satisfactory safety. Thus, phytol has potential as a safe and cost-effective addition to antischistosomal therapy. PMID:24392173

  10. Cerebral Schistosomiasis Caused by Schistosoma mansoni: a Case Report with Clinical Analysis

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    M Li

    2009-05-01

    Full Text Available "nCentral nervous system involvement arising from schistosomiasis is uncommon. It may be produced most fre­quently by Schistosoma japonicum infection, but reports of S. mansoni presenting as an intracerebral mass lesion are particularly rare. The authors describe the case of a 35-year-old woman with a 3-month history of partial epilep­tic seizures and head­aches. She immigrated to Egypt 4 years ago and had worked in Iraq for 2 years after the immigration. The patient's gen­eral physical and neurological examinations were unremarkable. Magnetic resonance (MR imaging revealed an enhanc­ing lesion with surrounding edema and mild mass effect in the left frontal lobe. A stereotactic brain biopsy demonstrated intraparenchymal granulomas surrounding S. mansoni eggs. S. mansoni was identified by stool examination. Prednisone (1 mg/kg per day for 1 week, with gradual with­drawal during the following 3 weeks and praziquantel (2 doses at 20 mg/kg per day therapy was initiated. The patient's symptoms resolved following medical treatment and the follow-up MR imaging yielded normal findings. This case is the rare imported case of cerebral schistosomiasis in China and the neuroschistosomiasis should be considered as the patient lived in a region in which this disease is endemic.

  11. Cytokine Pattern of T Lymphocytes in Acute Schistosomiasis mansoni Patients following Treated Praziquantel Therapy

    Science.gov (United States)

    Silveira-Lemos, Denise; Fernandes Costa-Silva, Matheus; Cardoso de Oliveira Silveira, Amanda; Azevedo Batista, Mauricio; Alves Oliveira-Fraga, Lúcia; Soares Silveira, Alda Maria; Barbosa Alvarez, Maria Carolina; Martins-Filho, Olindo Assis; Gazzinelli, Giovanni; Corrêa-Oliveira, Rodrigo; Teixeira-Carvalho, Andréa

    2013-01-01

    Acute schistosomiasis is associated with a primary exposure and is more commonly seen in nonimmune individuals traveling through endemic regions. In this study, we have focused on the cytokine profile of T lymphocytes evaluated in circulating leukocytes of acute Schistosomiasis mansoni-infected patients (ACT group) before and after praziquantel treatment (ACT-TR group). Our data demonstrated increased values of total leukocytes, eosinophils, and monocytes in both groups. Interestingly, we have observed that patients treated with praziquantel showed increased values of lymphocytes as compared with noninfected group (NI) or ACT groups. Furthermore, a decrease of neutrophils in ACT-TR was observed when compared to ACT group. Analyses of short-term in vitro whole blood stimulation demonstrated that, regardless of the presence of soluble Schistosoma mansoni eggs antigen (SEA), increased synthesis of IFN-γ and IL-4 by T-cells was observed in the ACT group. Analyses of cytokine profile in CD8 T cells demonstrated higher percentage of IFN-γ and IL-4 cells in both ACT and ACT-TR groups apart from increased percentage of IL-10 cells only in the ACT group. This study is the first one to point out the relevance of CD8 T lymphocytes in the immune response induced during the acute phase of schistosomiasis. PMID:23401741

  12. Assessment of control and epidemiologic details of the schistosomiasis mansoni in Bananal, São Paulo, Brazil

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    Horacio Manuel Santana Teles

    2014-06-01

    Full Text Available The purpose of our study in the municipality of Bananal, state of São Paulo, Brazil, was to stop the transmission of schistosomiasis mansoni. Particular emphasis was given to such items as the active surveillance and eventual treatment of hosts, mapping parasite foci, and increasing the extent of basic sanitation in the municipality. Now, our records indicate that the eradication of schistosomiasis in the municipality of Bananal is attainable. However, as the vector Biomphalaria tenagophila can still be found in some water bodies within this municipality, it remains included in the area where schistosomiasis is endemic, which calls for very strict measures to avoid the human cases of schistososomiasis. The expansion of the coverage of the basic sanitation network and treatment of Schistosoma mansoni cases diagnosed during periodic surveys are part of the plans to eradicate schistosomiasis in Bananal.

  13. Susceptibility of Argentinean Biomphalaria tenagophila and Biomphalaria straminea to infection by Schistosoma mansoni and the possibility of geographic expansion of mansoni schistosomiasis

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    Luciana Franceschi Simoes

    2013-10-01

    Full Text Available Introduction Human migration and the presence of natural vectors (mollusks of Schistosoma mansoni are the primary causes of the expansion of mansoni schistosomiasis into southern areas of South America. Water conditions are favorable for the expansion of this disease because of the extensive hydrographic network, which includes the basins of the Paraná and Uruguay rivers and favors mollusk reproduction. These rivers also aid agriculture and tourism in the area. Despite these favorable conditions, natural infection by S. mansoni has not yet been reported in Argentina, Uruguay, or Paraguay. Methods Two species of planorbid from Argentina, Biomphalaria straminea and B. tenagophila, were exposed to the miracidia of five Brazilian strains of S. mansoni. Results Biomphalaria tenagophila (Atalaya, Buenos Aires province was infected with the SJS strain (infection rate 3.3%, confirming the experimental susceptibility of this Argentinian species. Biomphalaria straminea (Rio Santa Lucía, Corrientes province was susceptible to two Brazilian strains: SJS (infection rate 6.7% and Sergipe (infection rate 6.7%. Conclusions These results demonstrate that species from Argentina have the potential to be natural hosts of S. mansoni and that the appearance of foci of mansoni schistosomiasis in Argentina is possible.

  14. Miltefosine Lipid Nanocapsules for Single Dose Oral Treatment of Schistosomiasis Mansoni: A Preclinical Study.

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    Maha M Eissa

    Full Text Available Miltefosine (MFS is an alkylphosphocholine used for the local treatment of cutaneous metastases of breast cancer and oral therapy of visceral leishmaniasis. Recently, the drug was reported in in vitro and preclinical studies to exert significant activity against different developmental stages of schistosomiasis mansoni, a widespread chronic neglected tropical disease (NTD. This justified MFS repurposing as a potential antischistosomal drug. However, five consecutive daily 20 mg/kg doses were needed for the treatment of schistosomiasis mansoni in mice. The present study aims at enhancing MFS efficacy to allow for a single 20mg/kg oral dose therapy using a nanotechnological approach based on lipid nanocapsules (LNCs as oral nanovectors. MFS was incorporated in LNCs both as membrane-active structural alkylphospholipid component and active antischistosomal agent. MFS-LNC formulations showed high entrapment efficiency (EE%, good colloidal properties, sustained release pattern and physical stability. Further, LNCs generally decreased MFS-induced erythrocyte hemolytic activity used as surrogate indicator of membrane activity. While MFS-free LNCs exerted no antischistosomal effect, statistically significant enhancement was observed with all MFS-LNC formulations. A maximum effect was achieved with MFS-LNCs incorporating CTAB as positive charge imparting agent or oleic acid as membrane permeabilizer. Reduction of worm load, ameliorated liver pathology and extensive damage of the worm tegument provided evidence for formulation-related efficacy enhancement. Non-compartmental analysis of pharmacokinetic data obtained in rats indicated independence of antischistosomal activity on systemic drug exposure, suggesting possible gut uptake of the stable LNCs and targeting of the fluke tegument which was verified by SEM. The study findings put forward MFS-LNCs as unique oral nanovectors combining the bioactivity of MFS and biopharmaceutical advantages of LNCs

  15. Miltefosine Lipid Nanocapsules for Single Dose Oral Treatment of Schistosomiasis Mansoni: A Preclinical Study.

    Science.gov (United States)

    Eissa, Maha M; El-Moslemany, Riham M; Ramadan, Alyaa A; Amer, Eglal I; El-Azzouni, Mervat Z; El-Khordagui, Labiba K

    2015-01-01

    Miltefosine (MFS) is an alkylphosphocholine used for the local treatment of cutaneous metastases of breast cancer and oral therapy of visceral leishmaniasis. Recently, the drug was reported in in vitro and preclinical studies to exert significant activity against different developmental stages of schistosomiasis mansoni, a widespread chronic neglected tropical disease (NTD). This justified MFS repurposing as a potential antischistosomal drug. However, five consecutive daily 20 mg/kg doses were needed for the treatment of schistosomiasis mansoni in mice. The present study aims at enhancing MFS efficacy to allow for a single 20mg/kg oral dose therapy using a nanotechnological approach based on lipid nanocapsules (LNCs) as oral nanovectors. MFS was incorporated in LNCs both as membrane-active structural alkylphospholipid component and active antischistosomal agent. MFS-LNC formulations showed high entrapment efficiency (EE%), good colloidal properties, sustained release pattern and physical stability. Further, LNCs generally decreased MFS-induced erythrocyte hemolytic activity used as surrogate indicator of membrane activity. While MFS-free LNCs exerted no antischistosomal effect, statistically significant enhancement was observed with all MFS-LNC formulations. A maximum effect was achieved with MFS-LNCs incorporating CTAB as positive charge imparting agent or oleic acid as membrane permeabilizer. Reduction of worm load, ameliorated liver pathology and extensive damage of the worm tegument provided evidence for formulation-related efficacy enhancement. Non-compartmental analysis of pharmacokinetic data obtained in rats indicated independence of antischistosomal activity on systemic drug exposure, suggesting possible gut uptake of the stable LNCs and targeting of the fluke tegument which was verified by SEM. The study findings put forward MFS-LNCs as unique oral nanovectors combining the bioactivity of MFS and biopharmaceutical advantages of LNCs, allowing targeting

  16. Association of oxamniquine praziquantel and clonazepam in experimental Schistosomiasis mansoni

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    Neusa Araujo

    2008-12-01

    Full Text Available The antischistosomal activity of clonazepam, when administered alone or in association with oxamniquine and praziquantel, was experimentally evaluated in mice infected with Schistosoma mansoni. The animals were treated 45 days post-infection with a single dose, by oral route, according to three treatment schedules: clonazepam 25 mg/kg and sacrificed 15 min, 1h or 4 h after treatment; clonazepam 1.0, 2.5 or 10.0 mg/kg and sacrificed 15 days post-treatment or with the dose of 10 mg/kg in association with oxamniquine 50 mg/kg or praziquantel 200 mg/kg, single dose, orally, every schedule with a control group. The efficacy of the drugs in vivo was assessed by means of worm counts and their distribution in mesentery and liver, mortality and oogram changes. In the chemotherapeutic schedules used, clonazepam did not present antischistosomal activity and the result of the association of this drug with oxamniquine or praziquantel was not significantly different from the one obtained when these two last drugs were administered alone. In the in vitro experiments, the worms exposed to 0.6 mg/mL clonazepam remained motionless throughout the 8-day-period of observation, without egg-laying, whereas the worms of the control group showed normal movements, egg-laying and hatching of miracidia on the last day of observation. The results obtained in the present study confirm the action of clonazepam on S. mansoni adult worm, in vitro, causing total paralysis of males and females. However, no additive or synergistic effects were observed when clonazepam were used in association with oxamniquine or praziquantel.

  17. Activity of the artemether in experimental schistosomiasis mansoni

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    Neusa Araújo

    1991-01-01

    Full Text Available The action of the ether artemisinin (artemether on Shistosoma mansoni in mice and the hansters experimentally infected with the LE strain was studied. In mice, the drugs showed high schistosomicidal activity using a single intramuscular dose of 100 mg/Kg/day. By the oral route, this dose showed a low activity. Mice treated with a single intramuscular dose of 200 mg/Kg/day, and examined 15 days after treatment, presented 100% alteration of the oogram; when examined 45 days after treatment, the oogram was normal. With doses of 100 mg/Kg/day, i.m., during 3 or 5 consecutive days, the death rate of mice was very high. Morphologic analysis of the worms collected by perfusion of mice treated with a single dose of 100 mg/Kg/day, i.m., detected a marked decrease in the length of male and female forms, degenerative alterations in the parenchyma and in the reproductive system of the females, with reduction of vitellinic material and in ovary volume; the intestinal contents presented a marked despigmentation. In the male worms signifcant alteration was not apparent by optical microscopy.

  18. Monocyte chemotactic protein-1 (MCP-1 in patients with chronic schistosomiasis mansoni: evidences of subclinical renal inflammation.

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    Ana Lúcia P Hanemann

    Full Text Available The aim of this study is to investigate renal markers and the biomarker MCP-1 in patients with schistosomiasis mansoni. This is a cross-sectional study with 85 patients aged 5 to 48 years, with a confirmed diagnosis of schistosomiasis mansoni through the Kato-Katz method. The patients were divided in three groups: control (G-I; infected by S. mansoni before treatment (G-II and infected by S. mansoni after treatment (G-III. Renal function was evaluated by tubular and glomerular biomarkers and through urinary MCP-1. Patients' mean age was 23.2 ± 13 years. There was no statistically significant difference between the groups regarding tubular and glomerular function evaluated through the traditional biomarkers. MCP-1 was higher in G-II and G-III, when compared to G-I; p=0.009 and p=0.007, respectively. There was no difference when comparing groups G-II and G-III (p=0.892. Although it was not different among the groups, there was a significant correlation between albuminuria and MCP-1. There was a significant increase in urinary MCP-1 levels in patients with schistosomiasis mansoni, which was associated with albuminuria. This protein has a role in the recruitment of monocytes to injury and inflammation sites . The increase of MCP-1 in the urine evidences that there is silent renal inflammation in these patients and the inflammatory status is not interrupted by specific treatment of the offending agent. Our findings suggest that urinary MCP-1 can be a sensitive marker of renal injury in patients with schistosomiasis mansoni.

  19. O Mastomys natalensis como modelo alternativo nos estudos da esquistossomose mansoni experimental Mastomys natalensis as alternative model in studies on experimental schistosomiasis mansoni

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Moreira Campos

    1984-02-01

    Full Text Available Foram estudados aspectos da infecção e da imunidade experimentais em um roedor — o Mastomys natalensis — inoculado com a cepa LE (Belo Horizonte do Schistosoma mansoni, comparando os resultados com os do camundongo albino, animal tido como melhor modelo experimental. Os parâmetros estudados ofereceram resultados em tudo semelhantes aos encontrados em camundongos, com o M. natalensis se mostrando bastante sensível à infecção pelo S. mansoni, sendo de grande utilidade para os estudos da biologia do parasito e/ou observações da imu-nologia advinda da infecção. Somando-se a tal fato a grande reprodutividade do animal em cativeiro, a criação fácil, o manejo e a manutenção simples em laboratório, sugere-se que seja o M. natalensis usado como modelo experimental alternativo nos diversos estudos da esquistossomose mansoni.It was studied aspects of experimental infection and immunity in a rodent — Mastomys natalensis — infected by the LE strain of Schistosoma mansoni. The results were compared with those from albino mouse, that is an excellent animal for experimental schistosomiasis. The studied parameters showed similar results to those found in the mouse. M. natalensis is highly susceptible to S. mansoni infection, being very useful for biological studies and/or immunity observations about this kind of infection. In addition, the high reproduction rate in captivity, easy handling and unexpensive maintenance in laboratory, suggest that M. natalensis could be used as an alternative experimental model in schistosomiasis mansoni studies.

  20. Liver and serum soluble protein changes and pathomorphology in undernourished mice with acute Schistosomiasis mansoni

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    Eridan M. Coutinho

    1991-12-01

    Full Text Available Body, liver and spleen weights; histopathology of the liver, spleen and intestines; hepatic and serum soluble proteins changes were the parameters studied in undernourished Swiss albino mice experimentally infected with S. mansoni. Non-infected deficient animab had lower liver/body weight and spleen/body weight ratios as compared to the controls (22.60% casein group. Infected mice showed higher values regardless the type of diet. Undernourished infected subgroup showed a persistent exudative periovular reaction in the liver. Soluble hepatic proteins content and serum protein fractions appeared to be lower in the deficient infected mice. A significant difference was detected in the gammaglobulin fraction between infected and non-infected animals fed the control diet with higher values for the former. Our data suggest that the effects of malnutrition, per se, are sometimes more detrimental to the host than those due to Manson 's schistosomiasis.

  1. Surgical indication in Schistosomiasis mansoni portal hypertension: follow-up from 1985 to 2001

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    Maria José Conceição

    2002-10-01

    Full Text Available The study had the objective to evaluate the benefits of surgical indication for portal hypertension in schistosomiasis patients followed from 1985 to 2001. Schistosoma mansoni eggs were confirmed by at least six stool examinations or rectal biopsy. Clinical examination, abdominal ultrasonography, and digestive endoscopy confirmed the diagnosis of esophageal varices. A hundred and two patients, 61.3% male (14-53 years old were studied. Digestive hemorrhage, hypersplenism, left hypochondrial pain, abdominal discomfort, and hypogonadism were, in a decreasing order, the major signs and symptoms determining surgical indication. Among the surgical techniques employed, either splenectomy associated to splenorenal anastomosis or azigoportal desvascularization, esophageal gastric descompression and esophageal sclerosis were used. Follow-up of patients revealed that, independent on the technique utilized, a 9.9% of death occurred, caused mainly by digestive hemorrhage due to the persistence of post-treatment varices. The authors emphasize the benefits of elective surgical indication allowing a normal active life.

  2. Performance of POC-CCA® in diagnosis of schistosomiasis mansoni in individuals with low parasite burden.

    Science.gov (United States)

    Siqueira, Liliane Maria Vidal; Couto, Flavia Fernanda Bubula; Taboada, Diana; Oliveira, Áureo Almeida de; Carneiro, Nidia Francisca de Figueiredo; Oliveira, Edward; Coelho, Paulo Marcos Zech; Katz, Naftale

    2016-01-01

    Schistosomiasis, caused by Schistosoma mansoni, is a public health concern in Brazil. However, the most popular diagnostic method, the Kato-Katz technique, exhibits low sensitivity in low-endemicity areas. We aimed to compare the performance of an immunological assay, the point-of-care circulating cathodic antigen (POC-CCA®) test, with that of two parasitological techniques in a low-endemicity population. Our study included 141 individuals living in Estreito de Miralta, Minas Gerais, Brazil. Fecal samples were obtained from all participants and analyzed for schistosomiasis using two parasitological techniques: the Kato-Katz technique and the saline gradient technique. Additionally, POC-CCA® strips were utilized for testing urine samples. The results obtained by the different techniques were compared. Analysis of two or 24 slides using the Kato-Katz technique resulted in a positivity rate of 10.6% (15/141) or 19.1% (27/141), respectively. The saline gradient technique yielded a positivity rate of 17.0% (24/141). The prevalence according to both parasitological techniques was 24.1% (34/141). The POC-CCA® test yielded a positivity rate of 22.7% (32/141); however, the positivity rate was merely 2.1% if trace results were considered negative. The agreements observed between POC-CCA® and the parasitological techniques were good (Kappa indexes > 0.64). The POC-CCA® test was more sensitive than the two-slide Kato-Katz technique (p < 0.05) in detecting cases of S. mansoni infection when trace results were considered positive. These findings reinforce the importance of using multiple diagnostic techniques in low-endemicity areas for effective control of disease.

  3. Molecular and cellular basis of hepatic fibrogenesis in experimental schistosomiasis mansoni infection

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    David J. Wyler

    1992-01-01

    Full Text Available Morbidity in schistosomiasis mansoni occurs primaryly as a result of the complications of hepatic fibrosis. Yet, the pathogenesis of schistosomal hepatic fibrosis is poorly understood. The fact that hepatic egg granuloma is the hallmark of this infection suggests a potential role for granulomatous inflamation in hepatic fibrogenesis. Our studies in a murine schistosomiasis model indicate that hepatic granuloma cells secrete a variety of fibrogenic cytokines that may initiate the scarring process. Among these cytokines, we identified a novel protein that we designated fibroplast stimulating factor-1 (FsF-1. FsF-1 is a lymphokine that can stimulate fibroplast growth and matrix synthesis. A notable feature of hepatic fibrosis in this model is that production of FsF-1 and other granuloma-derived fibrogenic cytokines is down-regulated in chronic infection, an event that may be under immunological control. The spontaneous reduction of FsF-1 secretion presumably accounts for reduced scar formation late in infection of mice. In the context of relevant clinical studies, our findings engender the hypothesis that Symmer's fibrosis may develop in a small suppopulation of individuals as a result of immunogenetically-determined dysregulation of fibrogenic cytokine production.

  4. Efficacy of low-dose myrrh protocols in the treatment of experimental schistosomiasis mansoni: hepatic improvement without parasitologic cure

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    Rashad Abdul-Ghani

    2010-11-01

    Full Text Available Rashad Abdul-Ghani1, Naguiba Loutfy2, Manal Sheta3, Azza Hassan21Department of Medical Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen; 2Tropical Health Department, High Institute of Public Health, 3Department of Pathology, Medical Research Institute, Alexandria University, Alexandria, EgyptAbstract: There is a new trend of “back to nature” in searching for antischistosomal drugs, particularly after the concerns raised about the possible emergence of schistosome isolates resistant/tolerant to praziquantel as well as for their relative safety and fewer side effects. Many plant derivatives have been investigated for efficacy against the Egyptian strain of Schistosoma mansoni, but much attention has been paid to myrrh extract, which is a purified sap obtained from Commiphora molmol. This extract has been produced and marketed in Egypt as a pharmaceutical preparation, but with a great discrepancy in its antischistosomal activity in both experimental and clinical studies. Most previous experimental studies used myrrh in the dosing protocol of 500 mg/kg/day for five days. In the present study, we investigated the therapeutic efficacy of three low-dose myrrh protocols against experimental schistosomiasis mansoni. All these protocols showed no significant efficacy in reducing parasite burdens and tissue egg loads or in changing oogram patterns. Nevertheless, there was an amelioration of hepatic lesions, with reductions in mean counts of hepatic granulomas as well as marked healing of these granulomas.Keywords: Schistosoma mansoni, schistosomiasis mansoni, myrrh, Commiphora molmol, antischistosomal chemotherapy

  5. Hemostatic dysfunction is increased in patients with hepatosplenic schistosomiasis mansoni and advanced periportal fibrosis.

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    Luiz Arthur Calheiros Leite

    Full Text Available BACKGROUND: Schistosomiasis mansoni is an endemic parasitic disease and a public health problem in Northeast Brazil. In some patients, hepatic abnormalities lead to periportal fibrosis and result in the most severe clinical form, hepatosplenic schistosomiasis. This study aimed to evaluate whether abnormal blood coagulation and liver function tests in patients with hepatosplenic schistosomiasis (n = 55 correlate with the severity of their periportal fibrosis. METHODOLOGY/PRINCIPAL FINDINGS: Blood samples were used for liver function tests, hemogram and prothrombin time (International Normalized Ratio, INR. The blood coagulation factors (II, VII, VIII, IX and X, protein C and antithrombin IIa (ATIIa, plasminogen activator inhibitor 1 (PAI-1 and D-dimer were measured by photometry or enzyme linked immunosorbent assay. Hyperfibrinolysis was defined on the basis of PAI-1 levels and a D-dimer concentration greater than a standard cut-off of 483 ng/mL. Standard liver function tests were all abnormal in the patient group compared to healthy controls (n = 29, including raised serum transaminases (p<0.001 and lower levels of albumin (p = 0.0156. Platelet counts were 50% lower in patients, while for coagulation factors there was a 40% increase in the INR (p<0.001 and reduced levels of Factor VII and protein C in patients compared to the controls (both p<0.001. Additionally, patients with more advanced fibrosis (n = 38 had lower levels of protein C compared to those with only central fibrosis (p = 0.0124. The concentration of plasma PAI-1 in patients was one-third that of the control group (p<0.001, and D-dimer levels 2.2 times higher (p<0.001 with 13 of the 55 patients having levels above the cut-off. CONCLUSION/SIGNIFICANCE: This study confirms that hemostatic abnormalities are associated with reduced liver function and increased liver fibrosis. Of note was the finding that a quarter of patients with hepatosplenic schistosomiasis and

  6. Use of a new glass microfibre histamine release method to study the modulation of the host response in human schistosomiasis mansoni. Individuals with different degrees of exposure to the disease show differing antibody biological function

    DEFF Research Database (Denmark)

    Satti, M.Z.; Ebbesen, F.; Vennervald, B.

    1996-01-01

    A new glass microfibre histamine release method was used to study the modulation of the host response in human schistosomiasis mansoni to improve our understanding of the role of basophils in the development of immunity in schistosomiasis mansoni. The histamine release from umbilical cord blood b...

  7. Experiences with the control of schistosomiasis mansoni in two foci in Central Africa

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    B. Gryseels

    1992-01-01

    Full Text Available Experiences with population-based chemotherapy and other methods for the control of schistosomiasis mansoni in two subsaharan foci are described. In the forest area of Maniema (Zaire, intense transmission of Schistosoma mansoni, high prevalences and intensities of infection, and important morbidity have been documental. Taking into account the limited financial means and the poor logistic conditions, the control strategy has been based mainly on targeted chemotherapy of heavily infected people (>600 epg. After ten years of intervention, prevalences and intensities have hardly been affected, but the initial severe hepatosplenic morbidity has almost disappeared. In Burundi, a national research and control programme has been initiated in 1982. Prevalences, intensities and morbidity were moderate, transmission was focal and erratic in time and space. A more structural control strategy was developed, based on screening and selective therapy, health education, sanitation and domestic water supply. Prevalences and intensities have been considerably reduced, though the results show focal and unpredicatable variations. Transmission and reinfection were not signifcantly affected by chemotherapy alone, and eventual outcome of repeated selective treatment appears to be limited by the sensitivity of the screening method. Intestinal morbidity was strongly reduced by community-based selective treatment, but hepatosplenic enlargement was hardly affected; this is possibly due to the confounding impact of increasing malaria morbidity. The experiences show the importance of local structures and conditions for the development of an adapted control strategy. It is further concluded that population-based chemotherapy is a highly valid tool for the rapid control of morbidity, but should in most operational conditions not be considered as a tool for transmission control. Integration of planning, execution and surveillance in regular health services...

  8. Chronic hepatosplenic schistosomiasis mansoni: magnetic resonance imaging and magnetic resonance angiography findings

    Energy Technology Data Exchange (ETDEWEB)

    Bezerra, A.S.; D' Ippolito, G.; Caldana, R.P.; Cecin, A.O.; Ahmed, M.; Szejnfeld, J. [Dept. of Diagnostic Imaging, Federal Univ. of Sao Paulo, Sao Paulo (Brazil)

    2007-02-15

    Purpose: To evaluate the hepatosplenic manifestations and the portal venous system in patients with chronic infection by Schistosoma mansoni. Material and Methods: A cross-sectional observational study was performed in 28 patients with chronic hepatosplenic schistosomiasis submitted to magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) of the abdomen. Images were interpreted independently by two radiologists to determine the reproducibility of image interpretation and who evaluated the presence of morphological alterations in the liver and spleen, such as hepatosplenomegaly, hepatic fissure widening, periportal fibrosis, and the presence of siderotic nodules. Interobserver and intra-observer agreement were measured with the kappa and intraclass correlation tests. Evaluation of venous collateral pathways and portal and splenic veins was done in consensus by both examiners. Results: Observers identified enlargement of the left lobe (78.5-92.8%) and caudate-to-right-lobe ratio (78.5-92.8%), irregularity of hepatic contours (89.2-96.4%), fissure widening (89.2-100%), and splenic siderotic nodules (84.2%). Splenomegaly, heterogeneity of hepatic parenchyma, peripheral hepatic vessels, and periportal fibrosis were observed in 100% of patients. MRI findings presented almost perfect interobserver (kappa 0.65-1) and intra-observer (kappa = 0.73-1 for observer 1, and kappa = 0.65-1 for observer 2) agreement for the variables analyzed. MRA showed the presence of collateral pathways in the majority of patients (71.4%) along with widening of portal and splenic veins. Conclusion: Using MRI, hepatosplenic alterations in schistosomiasis are characterized by heterogeneity of hepatic parenchyma, presence of peripheral perihepatic vessels, periportal fibrosis, splenomegaly, siderotic nodules, and the presence of venous collateral pathways.

  9. Liver and serum soluble protein changes and pathomorphology in undernourished mice with acute Schistosomiasis mansoni

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    Eridan M. Coutinho

    1991-12-01

    Full Text Available Body, liver and spleen weights; histopathology of the liver, spleen and intestines; hepatic and serum soluble proteins changes were the parameters studied in undernourished Swiss albino mice experimentally infected with S. mansoni. Non-infected deficient animab had lower liver/body weight and spleen/body weight ratios as compared to the controls (22.60% casein group. Infected mice showed higher values regardless the type of diet. Undernourished infected subgroup showed a persistent exudative periovular reaction in the liver. Soluble hepatic proteins content and serum protein fractions appeared to be lower in the deficient infected mice. A significant difference was detected in the gammaglobulin fraction between infected and non-infected animals fed the control diet with higher values for the former. Our data suggest that the effects of malnutrition, per se, are sometimes more detrimental to the host than those due to Manson 's schistosomiasis.No presente estudo os pesos corporal, hepático e esplénico; a morfologia patológica do fígado, baço e intestinos; e as modificações das proteínas solúveis hepáticas e séricas, foram os parâmetros investigados em camundongos albinos Suíços desnutridos e infectados com S. mansoni. Os animais desnutridos não infectados apresentaram relações fígado/peso corporal e baço! peso corporal com valores menores do que os animais controles (grupo caseina a 22,60%. Camundongos infectados mostraram esses índices mais elevados, independentemente do tipo de dieta. O subgrupo de camundongos desnutridos infectados apresentou, no fígado, reação periovular exsudativa persistente. O conteúdo de proteínas solúveis no fígado e no soro também mostrou-se reduzido nos camundongos infectados desnutridos. Diferença significativa foi detectada quanto às gamaglobulinas, comparando-se animais infectados com não infectados alimentados com a dieta controle II, valores mais altos ocorrendo no grupo dos

  10. Esquistossomose mansônica simulando neoplasia da bexiga Schistosomiasis mansoni simulating bladder neoplasia

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    Eduardo José Andrade Lopes

    2006-06-01

    Full Text Available Paciente de 36 anos de idade, proveniente de zona endêmica foi admitido com episódios de hematúria macroscópica total e disúria terminal. A citoscopia mostrou um tumor exofítico na parede anterior da bexiga, sugestivo de câncer. A biópsia revelou esquistossomose mansônica. Ressecção transuretral confirmou o diagnóstico. O paciente foi clinicamente tratado com oxamniquine, obtendo cura. O caso apresentado nesse trabalho enfatiza que nem todos os tumores de bexiga com hematúria microscópica são cânceres de bexiga.A 36-year-old patient, proceeding from an endemic area was admitted with episodes of total microscopic hematuria and terminal dysuria. Cytoscopy showed a protuberant tumor in the bladder anterior wall, suggestive of cancer. Biopsy revealed schistosomiasis mansoni. Transurethral resection confirmed the diagnosis. The patient was clinically treated and cured with oxamniquine. The case presented in this work emphasizes that not all the tumors of bladder with microscopic hematuria are bladder cancers.

  11. Prophylactic effect of artemether on human schistosomiasis mansoni among Egyptian children: A randomized controlled trial.

    Science.gov (United States)

    Elmorshedy, Hala; Tanner, Marcel; Bergquist, Robert N; Sharaf, Soraya; Barakat, Rashida

    2016-06-01

    A double-blind, randomized controlled trial was conducted in an endemic focus for Schistosoma mansoni in Kafr El-Sheikh Governorate, Northern Nile Delta, Egypt, to evaluate the prophylactic effect of artemether (ART) given in conjunction with praziquantel (PZQ). The study encompassed 913 primary school children randomly assigned to two treatment groups PZQ/ART and PZQ/ART-placebo. At baseline, both groups received 40 mg/kg body weight of PZQ twice four weeks apart, after which one group received 6 mg/kg body weight of ART every 3 weeks in 5 cycles during the transmission season and the other group received ART-placebo. At the end of the study, prevalence of infection among the PZQ/ART was approximately half that of the PZQ/ART-placebo group, i.e. 6.7% versus 11.6%, and incidence of new infections for the PZQ/ART was 2.7% versus 6.5% for the PZQ/ART-placebo. In conclusion, PZQ/ART combined therapy might be considered as an adjunct measure against human schistosomiasis, by specifically reducing transmission and therefore contribute to disease elimination. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  12. Freshwater snails and schistosomiasis mansoni in the State of Rio de Janeiro, Brazil: I - metropolitan mesoregion

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    Thiengo Silvana C

    2001-01-01

    Full Text Available In order to elaborate a planorbid chart of the State of Rio de Janeiro a survey of freshwater gastropods in the Metropolitan Mesoregion of this State was performed and revealed the occurrence of 20 species: Antillorbis nordestensis (Lucena, 1954; Biomphalaria glabrata (Say, 1818; Biomphalaria schrammi (Crosse, 1864; Biomphalaria straminea (Dunker, 1848; Biomphalaria tenagophila (Orbigny, 1835; Burnupia sp.; Drepanotrema anatinum (Orbigny, 1835; Drepanotrema cimex (Moricand, 1839; Drepanotrema lucidum (Pfeiffer, 1839; Ferrissia sp.; Gundlachia ticaga (Marcus & Marcus, 1962; Heleobia davisi Silva & Thomé, 1985; Lymnaea columella Say, 1817; Melanoides tuberculatus (Müller, 1774; Physa cubensis Pfeiffer, 1839; Physa marmorata Guilding, 1828; Pomacea sp.; Pomacea canaliculata (Lamarck, 1822; Pomacea lineata (Spix, 1827 and Pomacea sordida (Swainson, 1823. Among the planorbid species B. tenagophila was the most frequent, occurring in all municipalities surveyed. The present study extends the distribution of B. straminea in the State of Rio de Janeiro and reports new records for A. nordestensis, B. schrammi, G. ticaga, H. davisi and the genera Burnupia and Ferrissia. An account about the current transmission areas of schistosomiasis mansoni in this Mesoregion is presented as well.

  13. Histomorphometry of hepatic portal fibrosis in patients with surgical schistosomiasis mansoni

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    Brandt Carlos Teixeira

    2002-01-01

    Full Text Available The usual histology report of hepatic fibrosis in patients with hepatosplenic schistosomiasis mansoni presents no association with hemodynamic and clinical liver parameters. Histomorphometry is adding a new tool of investigation for measuring density of portal fibrosis in these patients. This investigation was set up for assessing a possible agreement between the well-accepted international classification and the fibrosis density grades measured by histomorphometry. Thirty-five children and equal number of adults were included in this study. All patients underwent splenectomy and ligature of the left gastric vein. Histology findings were assessed in surgical liver biopsy stained with Masson trichrome. The official histology report was used as reference. The histomorphometric studies were done by semi-automatic morphometry. The mean percentage (X of portal fibrosis plus or minus one standard deviation (SD was classified as grade II (7.06% up to 34.72%; grade I was up to 7.06%; and grade III above 34.72%. Although, not reaching statistical significance, there is a tendency of the fibrosis to be more intense in children than adults (X±SD - 22.02±13.46% versus 20.63%±15.33% "t" = 0.379 p>0.05. Seven out of nine (77.8% patients classified as grade I, by morphometry, had the same result on the official report, however, two (22.2% were described as grade III. Sixteen out of forty-four (36.4% classified as grade II on morphometry had the same classification as the histology grade, but, twenty seven (61.4% were classified as grade III and one (2.3% as grade I. Fifteen (21.4% out of 70 patients had grade III on both classifications, but, two (11.8% out of seventeen G III on morphometry were grade II. The kappa (k measurement of agreement between both classification was k = 0.319, showing a fair strength of association. The histomorphometric measurements of Symmers fibrosis in surgical patients with mansonic schistosomiasis partially support the report

  14. Schistosoma mansoni

    DEFF Research Database (Denmark)

    Friis, Henrik; Byskov, Jens

    1987-01-01

    Recent surveys in Ngamiland, Botswana, indicate increasing prevalence of Schistosoma mansoni infections. With the introduction of a schistosomiasis control programme, 354 of 373 schoolchildren were examined quantitatively for eggs of S. mansoni, and 317 were examined clinically for hepato- and sp...... with enlarged spleen. 21 of these had schistosomiasis. The prevalence of hepatomegaly was highest among those excreting above 1600 epg. Also the mean size of the enlarged livers increased with intensity of infection....

  15. Esquistossomose mansônica em camundongos experimentalmente subnutridos Mansoni schistosomiasis in experimentally undernourished mice

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    Luiz Augusto Magalhães

    1986-10-01

    Full Text Available Realizou-se estudo sobre o desenvolvimento da esquistossomose mansônica em camundongos submetidos à dieta hipoprotéica. Foram constituídos 4 grupos de Mus musculus "Swiss" da seguinte forma: 1 não infectados, normoprotéicos; 2 infectados, normoprotéicos; 3 não infectados, hipoprotéicos e 4 infectados, hipoprotéicos. Os animais foram sacrificados com 60 dias de infecção, aos 90 dias de idade. Verificou-se que os esquistossomos sofreram os efeitos da subnutrição do hospedeiro, principalmente os vermes machos, que além de terem seu desenvolvimento prejudicado, tiveram seu número reduzido aproximadamente pela metade. O número de granulomas foi menor nos roedores subnutridos e o tamanho da lesão foi reduzido. Houve acentuada leucopenia nos animais submetidos à dieta hipoprotéica, principalmente nos infectados subnutridos. A linfopenia e a eosinopenia acentuadas sugeriram que o sistema imunológico do hospedeiro foi afetado pela subnutrição. A taxa de mortalidade foi muito mais elevada nos animais infectados submetidos à dieta hipoprotéica. Concluiu-se que os camundongos subnutridos resistiram menos à infecção esquistossomótica apesar de terem apresentado menor número de lesões granulomatosas.Mansoni schistosomiasis was studied in mice fed on a low protein diet. Four groups of the Swiss breed Mus musculus were used in an experiment with two factors, each with two levels: 1-non-infected, normal diet; 2 - infected, normal diet ; 3 - non-infected, low protein diet; 4 - infected, low protein diet. The mice were killed for observation at age 90 days, after 60 days of infection, for those infected. It was found that the worms suffered the effects of malnutrition, mainly males, whose population count was cut by half, in addition to poor individual growth. The hepatic granuloma count was found to be smaller in the undernourished group; while the corresponding lesions were also generally smaller. There was a marked leukopenia in

  16. Idiotype/anti-idiotype immunoregulatory network correlates with an improved clinical outcome of schistosomiasis mansoni in humans.

    Science.gov (United States)

    Abdeen, Sherif H

    2011-03-15

    Anti-idiotypes (anti-Ids) have a potential role in the immune modulation of various diseases. To study the correlation of anti-Ids with schistosomiasis mansoni morbidity, ELISA using polyclonal idiotypes (Ids) was used to determine the presence of anti-Ids in sera of 69 patients susceptible and resistant to reinfection. Ids were purified against Soluble Worm Antigen (SWAP) from sera of New Zealand white rabbits immunized with SWAP. The results showed that anti-Ids were detected in 15 (40.5%) of susceptible and 21 (65.6%) of resistant patients. Correlation of intensity of infection with age revealed an inverse relationship in patients positive for anti-Ids (regression coefficient beta = -0.47, p Ids (beta = 0.67, p Ids and the lack of schistosome-related symptoms (chi2 = 3.6, p Ids revealed that those negative for anti-Ids were more vulnerable to develop symptoms (3.7 times) and hepatomegaly (8.1 times). In conclusion, the study further confirms the role of Id/anti-Id regulatory network as an important participant in the assortment of an improved clinical outcome of schistosomiasis. This may help to formulate a better understanding of the mechanisms of protective immunity in humans and provide perspective for the development of a future vaccine.

  17. Dificuldades no desenvolvimento de uma vacina para a esquistossomose mansoni Problems in the development of a vaccine against schistosomiasis mansoni

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    Naftale Katz

    1999-12-01

    Full Text Available Nas últimas duas décadas, os estudos com antígenos que possam conferir imunidade protetora à infecção experimental pelo Schistosoma mansoni tiveram grande impulso, especialmente devido ao avanço dos conhecimentos nos campos da biologia molecular e da imunologia. Embora, estes estudos tenham trazidos novas e importantes contribuições, até o momento, a proteção conferida tem girado em torno de 50% de diminuição do número de vermes e com alguns antígenos, também do número de ovos. As muitas perguntas ainda não respondidas indicam a necessidade de novas pesquisas a serem realizadas em animais de pequeno e grande porte, antes que estes antígenos candidatos a vacina, possam ser utlizados em ensaios clínicos.During the last two decades, studies on antigens that may confer protective immunity to experimental infection with Schistosoma mansoni have made great advances, due largely to increased knowledge in the fields of molecular biology and immunology. Although these studies have made new and important contributions, at the present time the degree of protection conferred remains at approximately 50% in reducing the number of flukes and, with some antigens, the number of eggs. The many questions still to be answered indicate the necessity of carrying out further research on small and large animals before these antigen candidates for vaccines can be used in clinical tests.

  18. Freshwater snails and Schistosomiasis mansoni in the state of Rio de Janeiro, Brazil: III - Baixadas Mesoregion

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    Silvana C Thiengo

    2002-10-01

    Full Text Available In this paper, the third of a series dealing with the survey of freshwater gastropods of the state of Rio de Janeiro, the results of collections carried out in the Mesoregion Baixadas from 2000 to 2002 are presented. Twenty-two species, belonging to seven families, were found. As to the snail intermediate hosts of Schistosoma mansoni, the most frequent species was Biomphalaria tenagophila besides some new findings of Biomphalaria straminea. No specimens were found harboring larval forms of S. mansoni although different kinds of cercariae had been observed.

  19. Evaluation of the Schistosoma mansoni Y-box-binding protein (SMYB1 potential as a vaccine candidate against schistosomiasis

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    Silvia Regina Costa Dias

    2014-06-01

    Full Text Available Schistosomiasis is a neglected tropical disease, and after malaria, is the second most important tropical disease in public health. A vaccine that reduces parasitemia is desirable to achieve mass treatment with a low cost. Although potential antigens have been identified and tested in clinical trials, no effective vaccine against schistosomiasis is available. Y-box-binding proteins (YBPs regulate gene expression and participate in a variety of cellular processes, including transcriptional and translational regulation, DNA repair, cellular proliferation, drug resistance and stress responses. The Schistosoma mansoni ortholog of the human YB-1, SMYB1, is expressed in all stages of the parasite life cycle. Although SMYB1 binds to DNA or RNA oligonucleotides, immunohistochemistry assays demonstrated that it is primarily localized in the cytoplasm of parasite cells. In addition, SMYB1 interacts with a protein involved in mRNA processing, suggesting that SMYB1 functions in the turnover, transport and/or stabilization of RNA molecules during post-transcriptional gene regulation. Here we report the potential of SMYB1 as a vaccine candidate. We demonstrate that recombinant SMYB1 stimulates the production of high levels of specific IgG1 antibodies in a mouse model. The observed levels of specific IgG1 and IgG2a antibodies indicate an actual protection against cercariae challenge. Animals immunized with rSMYB1 exhibited a 26% reduction in adult worm burden and a 28% reduction in eggs retained in the liver. Although proteins from the worm tegument are considered optimal targets for vaccine development, this study demonstrates that unexposed cytoplasmic proteins can reduce the load of intestinal worms and the number of eggs retained in the liver.

  20. Evaluation of the Schistosoma mansoni Y-box-binding protein (SMYB1) potential as a vaccine candidate against schistosomiasis.

    Science.gov (United States)

    Dias, Sílvia R C; Boroni, Mariana; Rocha, Elizângela A; Dias, Thomaz L; de Laet Souza, Daniela; Oliveira, Fabrício M S; Bitar, Mainá; Macedo, Andrea M; Machado, Carlos R; Caliari, Marcelo V; Franco, Glória R

    2014-01-01

    Schistosomiasis is a neglected tropical disease, and after malaria, is the second most important tropical disease in public health. A vaccine that reduces parasitemia is desirable to achieve mass treatment with a low cost. Although potential antigens have been identified and tested in clinical trials, no effective vaccine against schistosomiasis is available. Y-box-binding proteins (YBPs) regulate gene expression and participate in a variety of cellular processes, including transcriptional and translational regulation, DNA repair, cellular proliferation, drug resistance, and stress responses. The Schistosoma mansoni ortholog of the human YB-1, SMYB1, is expressed in all stages of the parasite life cycle. Although SMYB1 binds to DNA or RNA oligonucleotides, immunohistochemistry assays demonstrated that it is primarily localized in the cytoplasm of parasite cells. In addition, SMYB1 interacts with a protein involved in mRNA processing, suggesting that SMYB1 functions in the turnover, transport, and/or stabilization of RNA molecules during post-transcriptional gene regulation. Here we report the potential of SMYB1 as a vaccine candidate. We demonstrate that recombinant SMYB1 stimulates the production of high levels of specific IgG1 antibodies in a mouse model. The observed levels of specific IgG1 and IgG2a antibodies indicate an actual protection against cercariae challenge. Animals immunized with rSMYB1 exhibited a 26% reduction in adult worm burden and a 28% reduction in eggs retained in the liver. Although proteins from the worm tegument are considered optimal targets for vaccine development, this study demonstrates that unexposed cytoplasmic proteins can reduce the load of intestinal worms and the number of eggs retained in the liver.

  1. Evaluation of a 25-year-program for the control of schistosomiasis mansoni in an endemic area in Brazil.

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    Ana K Sarvel

    Full Text Available BACKGROUND: Various studies showed that chemotherapy can control schistosomiasis morbidity, but association of measures (water supply, sewage disposal and increase of socioeconomic conditions is necessary for transmission control. METHODOLOGY/PRINCIPAL FINDINGS: A survey dealing with socioeconomic conditions, snail survey, contact with natural waters, and clinical and stool examinations was undertaken at an endemic area in the State of Minas Gerais, Brazil. The methodology used was the same for both evaluations (1981 and 2005. Four hundred and seventy-five out of 1,474 individuals studied in 1981 could be contacted. From these, 358 were submitted to stool examination, and 231 of them were clinically examined. Patients eliminating S. mansoni eggs in their stools were treated. The results showed that the prevalence rate in Comercinho, a municipality of the State of Minas Gerais, Brazil, was substantially reduced to 70.4% and 1.7% in 1981 and 2005, respectively, as well as the frequency of the hepatosplenic form (7% to 1.3% after five treatments effectuated between 1981 and 1992. No other new case of this form was detected from 1981 onwards. Another important aspect to be considered was the improvement of people's living standard that occurred in the region after more than two decades' efforts (better housing, professional skill and adequate basic sanitation. CONCLUSION/SIGNIFICANCE: The control of morbidity and very significant decrease of schistosomiasis transmission in an area until then considered as hyperendemic was possible by means of association of successive specific treatments of the local population, together with the construction of privies, water supply in the houses and improvement of socioeconomic conditions.

  2. Immunopathology of human schistosomiasis mansoni: II. NK activity and stimulation by specific antigen

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    L. K. Benarroch

    1988-12-01

    Full Text Available Sixteen S. mansoni infected and untreated patients (5 with recent infection and 11 with chronic disease were evaluated for their in vitro natural killer (NK activity against the NK sensitive target K562 cell line. NK levels in 9 out of 11 patients (82% with chronic disease were significantly lower (mean = 15 ± 6%,compared with patients recently infected (mean = 41 ± 9% p < 0.001 and with the control group (mean = 38 ± 13% p < 0.001. However, both patients and controls NK activity was stimulated by soluble adult worm antigens (SAWA, indicating that NK function even in the chronic stage of the infection is able to respond to the parasite antigens. These results suggest the possibility of NK cell participation as effector mechanism against S. mansoni.

  3. Schistosomiasis mansoni in Bananal (State of São Paulo, Brazil: II. Intermediate hosts

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    Horacio Manuel Santana Teles

    2002-10-01

    Full Text Available We conducted monthly snail captures in Bananal, State of São Paulo, Brazil, between March 1998 and February 2001, to identify Schistosoma mansoni vectors, estimate seasonal population changes, and delimit foci. We also evaluated the impact of improvements in city water supply and basic sanitation facilities. We identified 28,651 vector specimens, 28,438 as Biomphalaria tenagophila, 49 of them (0.2% infected with S. mansoni, and 213 as B. straminea, none of the latter infected. Vectors predominated in water bodies having some vegetation along their banks. Neither population density nor local vegetation could be linked to vector infection. We found the first infected snails in 1998 (from March to May. Further captures of infected snails ocurred, without exception, from July to December, when rainfall was least. Irrespective of season, overall temperature ranged from 16.5ºC to 21ºC; pH values, from 6.0 to 6.8. Neither factor was associated with snail population density. Frequent contact of people with the river result from wading across it, extracting sand from its bottom, fishing, washing animals, etc. Despite a marked reduction in contamination, cercaria shedding persists. Whatever the location along its urban course, contact with river Bananal, particularly of the unprotected skin, entails risks of infection.

  4. Schistosomiasis

    OpenAIRE

    Husnawati, Eka; Lusiyana, Novyan

    2016-01-01

    Schistosomiasis, also known as bilharzia, is a zoonosis disease caused by blood flukes (trematodes) of the genus Schistosoma sp. There are a few species that can infect humans and animals, including Schistosoma aponicum, Schistosoma mansonia, Schistosoma hematobium, Schistosoma intercalatum Schistosoma guineensis and Schistosoma mekongi.1 This disease is endemic in 78 countries, in which 52 of them are countries with moderate-high level of endemicity. Schistosoma sp are very difficult to elim...

  5. THE SCHISTOSOMULA TEGUMENT ANTIGEN AS A POTENTIAL CANDIDATE FOR THE EARLY SEROLOGICAL DIAGNOSIS OF SCHISTOSOMIASIS MANSONI

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    Rafaella Grenfell

    2013-04-01

    Full Text Available If Schistosoma mansoni infection could be detected in its early stages, especially before the egg deposition in the host tissues, the development of severe pathologic lesions could be efficiently prevented. We therefore developed an indirect enzyme-linked immunosorbent assay based on the detection of specific IgG against schistosomula antigens (ELISA-SmTeg. The assay was applied in sera samples from non-infected and infected mice collected seven and 15 days post-infection. The results were compared to the number of adult worms obtained by perfusion of the murine hepatic system 50 days post-infection. The sensitivity and specificity of the ELISA-SmTeg were 100% (p = 0.0032 and 0.0048 respectively for seven and 15 days of infection with a cutoff value of 0.15 (p = 0.0002. Our findings show a novel low-cost serological assay using antigens which are easy to obtain, which was able to detect all the infected mice as early as seven days post-infection.

  6. Sociocultural aspects of schistosomiasis mansoni in an endemic area in Minas Gerais, Brazil

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    Gazzinelli Andréa

    1998-01-01

    Full Text Available A study to determine the sociocultural factors influencing knowledge, attitudes, and practices of individuals from a small community toward Schistosoma mansoni infection was carried out in an endemic area in the State of Minas Gerais, Brazil. The study used qualitative approaches to collect data from school-aged children and teachers. Specific findings were that the individuals interviewed were aware of the disease, but also held inaccurate popular beliefs about transmission. Misconceptions coexisted with accurate knowledge both in children and teachers. The disease was not seen as a major health problem and did not affect their activities since it did not cause severe symptoms in most of the individuals. Although the majority of the participants related transmission to water and lack of sanitation, they did not take any preventive measures since their subsistence is highly dependent on irrigation, farming, fishing, and other essential work that is directly related to water activities. The authors discuss the development of a health education program based on the knowledge and perception of individuals about the disease and its determinants as being important for the context and behavioral change.

  7. Association of Schistosoma mansoni-Specific IgG and IgE Antibody Production and Clinical Schistosomiasis Status in a Rural Area of Minas Gerais, Brazil

    Science.gov (United States)

    Negrão-Corrêa, Deborah; Fittipaldi, Juliana F.; Lambertucci, José Roberto; Teixeira, Mauro Martins; Antunes, Carlos Maurício de Figueiredo; Carneiro, Mariângela

    2014-01-01

    Background Studies in murine models and human populations have indicated that the collagen-rich granulomatous response against parasite eggs trapped in the liver is associated with the development of severe hepatosplenic schistosomiasis, characterized by periportal fibrosis and portal hypertension. The role of the humoral response in parasite susceptibility has been well established, but its participation in disease severity remains poorly understood. In this work, we evaluated the relationship between parasite-reactive IgE and IgG levels and schistosomiasis morbidity in infected patients with similar parasite burdens. Methodology/Principal Findings Ninety-seven Schistosoma mansoni-infected individuals were subjected to clinical examination and abdominal ultrasound analysis. IgG reactivity and IgE concentration against Schistosoma mansoni soluble egg antigens (SEA) and adult worm antigen preparation (SWAP) were evaluated by ELISA assay. Multivariable linear regression models were used to evaluate the relationship between parasite-reactive antibodies and the co-variables investigated. The study population showed low parasite burden (median 30 eggs/g feces), constant re-infection, and signs of fibrosis was detected in more than 30% of individuals. Most infected individuals showed IgG reactivity, and the median concentrations of IgE anti-SEA and anti-SWAP antibodies were 1,870 and 1,375 ng/mL, respectively. There was no association between parasite burden and antibody response or any parameter of disease severity. However, IgG anti-SWAP level was positively associated with morbidity parameters, such as spleen size and thickness of portal vein at the entrance and secondary branch. In contrast, the data also revealed independent inverse correlations between concentration of parasite-reactive IgE and gallbladder wall thickness, a marker of fibrosis in schistosomiasis. Conclusions/Significance The data indicate that IgG anti-SWAP is positively associated with severe

  8. Bone mineral content reduction in youth with surgical form of Schistosomiasis mansoni: factors involved in the pathogenesis

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    Brandt Carlos Teixeira

    2001-01-01

    Full Text Available Thirty two children and adolescents from 14 to 20 years of age, suffering from hepatosplenic schistosomiasis mansoni and bleeding esophageal varicose veins, were evaluated for bone mineral density (BMD, before undergoing medical and surgical treatment. The surgical protocol was splenectomy, autoimplantation of spleen tissue into a pouch of the major omentum and ligature of the left gastric vein. Follow up of these patients? ranges from one to ten years with a mean of five years. The BMD was measured at the lumbar spine (L2 - L4 through the dual energy absorptionmetry X-ray (DEXA, using a LUNAR DPX-L densitometer. The degree of Symmers´ fibrosis was assessed by semiautomatic hystomorphometry. In eleven patients, the serum magnesium was measured before an intravenous overload of this ion and subsequently after eight and twenty four hours. Urine was collected 24 hours before and 24 hours after the magnesium overload. Deficiency of magnesium was considered when the uptake of this ion was greater than 40%. There was a significant trend of association between the status of bone mineral content and the Symmers´ fibrosis degree (c² = 6.606 R = 0.01017. There was also a moderate agreement between the greater fibrosis densities ( > the mean percentage and bone mineral deficits. Although the normal bone mineral content was more found among the patients with better hepatic functional reserve, the results did not reach statistical significance. There was a marked magnesium retention (>95% in one patient who had severe osteoporosis and a slight depletion (<5% in another patient, who presented no bone mineral deficit. It was concluded that the patients included in this series, showed an important BMD deficit, specially among the females which has had a significant improvement after medical and surgical treatment. Bone mineral deficit was associated with the degree of Symmers´ fibrosis. Magnesium depletion was present in two out of eleven patients. It is

  9. Tratamento da esquistossomose mansônica hepatesplênica com praziquantel Treatment of hepatosplenic schistosomiasis mansoni with praziquantel

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    Amaury D. Coutinho

    1984-02-01

    obter um maior porcentual de cura, sem prejuízo da boa tolerância. A melhora clínica e laboratorial a longo prazo, isto é, seis ou mais meses após a medicação, foi marcante em todos os parâmetros estudados.Ninety-four patients, 22 males and 72 females, from 11 to 71 years old, with an average of 25 years, presenting the hepatosplenic form of Schistosomiasis mansoni were treated with a new anthelmintic drug — praziquantel — to investigate its efficacy and tolerance. In addition to the hepatosplenic form of the disease, 14 patients had the cardio-pulmonary hypertensive or cyanotic form and 16 had already been submitted to splenectomy. Two oral doses — 1 x 30 and 2 x 25 mg/kg body weight — were compared. Side-effects were noticed during the first two days following the drug administration but usually of mild intensity and short duration. The most frequent and, at times, more severe were abdominal pain or discomfort, diarrhea, headache, dizziness and nausea. Fever was present in 19.2% of the cases and urticaria and pruritus in two patients. The laboratorial investigation of liver function showed, in some cases, slight enzymatic alterations (AST, ALT, y GT 24 hours after medication, but without any major significance. No urinary, blood glucose or hematological changes have been detected, except, for the commonly seen increase of eosinophyls on the 7th and 30th day, related to the death of parasites inside the organism. Likewise, no abnormality was noticed in the electroencephalografic study. In the electrocardiogram it was observed in two patients a slight and transitory modification on the ventricular repolarization. With regard to the parasitological cure, it was observed in 62 patients Who have finished the 6 months control period, a total cure rate of 80.6%. With 30 mg/kg single dose this cure rate was 76.7% and with 25 mg/kg b.i.d. 84.4%. The non-cured patients, on the other hand, have shown a marked reduction in the number of S. mansoni eggs eliminated

  10. Importância epidemiológica de alguns animais silvestres na esquistossomose mansônica Epidemiologic importance of some wild rodents in the schistosomiasis mansoni

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    Urara Kawazoe

    1983-10-01

    ência da contaminação humana, na natureza. Porém, é possível que, futuramente, H. b. leucogaster na presença de B. glabrata, possa servir de reservatório da esquistossomose, na natureza, quando encontrados em abundância e desde que adaptados com cepas adequadas do parasita.The importance of some wild rodents as possible reservoir hosts of S. mansoni related to the epidemiologic chain of this parasite and some biological aspects of these rodents were studied in semi-natural habitats. The experiment was performed in an enclosed area of about 1,000 m² situated in Taubaté, State of S. Paulo, one of the endemic area of human schistosomiasis, during a period of three years and six months (from August 1973 to December 1976. Wild rodents of the following species were used as definitive hosts: Holochilus brasiliensis leucogaster, Zygodontomys lasiurus, Oryzomys nigripes eliurus and Cavia aperea aperea. Biomphalaria tenagophila and B. glabrata were used as intermediate hosts. From August 1973 to January 1976 it was not possible to find any B. tenagophila eliminating S. mansoni cercariae nor any rodents infected with the same parasite. In August, 1975, egg patches of B. glabrata snails were accidentaly introduced into the area and in 1976 some adult snails were eliminating S. mansoni cercariae. In that same year, two Holochilus that were born in the area were discharging S. mansoni eggs in their feces. Some biological data were collected from 41 H. b. leucogaster of which 28 individuals were introduced into and 14 were born in the area. The majority of body weights of rodents born in the area and captured for the first time was between 20 and 50 grams. In this group of 41 rodents observed, body weight continued to increase throughout the life span of each individual sampled. Z. lasiurus and C. a. aperea did not show any infection with S. mansoni and they did not leave any progeny in the area. O. n. eliurus reproduced in the area and remaining there for about 100 days did

  11. Schistosomiasis mansoni presenting as a cerebellar tumor: case report Esquistossomose mansônica apresentando-se como tumor cerebelar: relato de caso

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    Joacil Carlos da Silva

    2007-09-01

    Full Text Available The Manson's schistosomiasis tumoral form rarely affects the brain. There are only 12 cases prior related with a mean age of 25 years and a male predominance. We describe a 16-year-old Brazilian Northeastern boy with a cerebellar mass lesion. The radiological aspect was considered compatible with glioma and a gross total resection was performed. Microscopic examination disclosed intraparenchymal granulomas surrounding Schistosoma mansoni eggs. The case is compared with the literature findings and some peculiar aspects of this trematode infection are reviewed.A forma pseudotumoral da esquistossomose mansônica raramente acomete o encéfalo. Apenas 12 casos foram previamente descritos com idade média de 25 anos e predominância do sexo masculino. Relatamos um caso em paciente do nordeste brasileiro de 16 anos portador de lesão expansiva cerebelar. O aspecto radiológico foi considerado compatível com tumor cerebelar primário e ressecção radical realizada. Estudo histopatológico demonstrou granulomas intraparenquimatosos contornando ovos de Schistosoma mansoni. O caso é comparado com os achados da literatura e aspectos peculiares dessa neuropasitose são discutidos.

  12. Schistosomiasis mansoni in three localities of western lowland of the state of Maranhão before and after mass treatments

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    Raimundo Nonato Martins Cutrim

    1992-12-01

    Full Text Available A cross-sectional study for schistosomiasis was carried out in the localities of Aliança, Alegre and Coroatá (districts of Cururupu, São Bento and São João Batista, respectively in the lowland of the state of Maranhão, after respectively 13, 11 and 4 mass treatments with oxamniquine in the period of ten years (1977-1987. The study included clinical and quantitative fecal examination, skin test for Shistosoma mansoni infection, evaluation of man-water contact of the total population (829 persons in the three localities and other epidemiological investigations such as infection rate and dynamics of the snail population. After 13 mass treatments in Aliança, the prevalence of S. mansoni infection was reduced from 57.9% to 7.4%. In Coroatá with 11 mass treatments the prevalence fell from 69.2% to 12.8% and in Alegre, with only 4 mass treatments there was pratically no reduction in prevalence: 22.9% to 21%. After mass treatments the type II hepatointestinal clinical form was 10.8% in Aliança, 17.9% in Alegre and 18% in Coroatá. The hepatosplenic (type III form was not seen in Aliança and Coroatá but unexplanably it was 7.6% in Alegre. There was no correlation between the egg load elimination and the clinical forms.

  13. Study of the Activity of 3-benzyl-5-(4-chloro-arylazo-4-thioxo-imidazolidin-2-one against Schistosomiasis Mansoni in Mice

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    Andréa Cristina Apolinário da Silva

    2012-01-01

    Full Text Available Previous studies conducted with the imidazolidinic derivative 3-benzyl-5-(4-chloro-arylazo-4-thioxo-imidazolidin-2-one (LPSF-PT05 show outstanding activity against adult Schistosoma mansoni worms in vitro. In the first phase of this study, S. mansoni-infected mice were treated, orally, with 100 mg/Kg of the LPSF-PT05 in three formulations: Tween 80 and saline solution, oil/water (70 : 30 emulsion, and solid dispersion with polyethylene glycol (PEG. In the second phase, three other doses of the LPSF-PT05 in PEG were tested: 3, 10, 30 mg/kg. These treatment regimens significantly reduced the number of recovered worms due to increases in the solubility of the compound in this formulation; the greatest reduction (70.5% was observed at the dose of 100 mg/kg. There was no changes in the pattern of mature egg compared to immature eggs; however there was a significant increase in the number of dead eggs. Histopathological analysis of liver tissue showed changes in morphological aspects of the hepatic parenchyma with decrease exudative-productive hepatic granuloma stages, although we found no significant differences in IFN-γ, IL-4, IL-10, or NO production in response to the specific antigen SEA. The results show the derivative LPSF-PT05 to be a potential candidate in the etiological treatment of schistosomiasis with a possible dampening effect of the granulomatous process.

  14. Efficacy of an enzyme-linked immunosorbent assay as a diagnostic tool for schistosomiasis mansoni in individuals with low worm burden

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    Edward José de Oliveira

    2005-07-01

    Full Text Available IgM-ELISA is an immunoenzymatic method useful for detection of IgM antibodies against a fraction of Schistosoma mansoni adult worm antigen (AWA that is soluble in trichloroacetic acid (AWA-TCA. This method was applied to three groups of individuals with different clinical and epidemiological characteristics, and the results compared with those obtained by other diagnostic methods: immunofluorescence test for detection of IgM antibodies (IgM-IFT or IgG antibodies (IgG-IFT, ELISA for detection of IgG antibodies (IgG-ELISA, and two parasitological methods, Kato-Katz and miracidium hatching. The IgM-ELISA presented a sensitivity of 98%, when the parasitologic fecal examination was defined as reference diagnostic method, and a specificity of 98 and 97.3%, respectively for the group of clinically healthy individuals and other helminth carriers. A comparative analysis between the results of IgM-ELISA and those obtained by other serologic tests showed a good degree of agreement, with Kappa indices ranging from 0.95 to 0.98. The diagnostic efficacy of 97.8%, as determined with schistosomiasis patients with low parasitic burden, suggests the excellent performance of the IgM-ELISA and its usefulness for the diagnosis of schistosomiasis when applied in low endemic areas.

  15. Serum And Tissue Enzymes And Trace Elements In Hamsters With Schistosomiasis Mansoni And/Or Protein Energy Malnutrition

    OpenAIRE

    Al Nagdy, Sohair A. [سهير علي النجدي; Saoud, M. F. A.; Morcos, N. Y. S.

    1996-01-01

    Schistosomiasis is mostly widespread in communities suffering from protein energy malnutrition. The development of an animal model for each condition is required for better understanding of changes in certain biochemical indices in pure schistosomiasis or pure energy malnutrition or both. Measurements of some enzymes as well as trace elements have been found to be valuable as diagnostic and prognostic indicators for tissue destruction. Accordingly, the present investigation reports measuremen...

  16. TGF beta and IL13 in Schistosomiasis mansoni associated pulmonary arterial hypertension; a descriptive study with comparative groups.

    Science.gov (United States)

    Ferreira, Rita de Cassia dos Santos; Montenegro, Silvia Maria Lucena; Domingues, Ana Lucia Coutinho; Bandeira, Angela Pontes; Silveira, Carlos Antonio da Mota; Leite, Luiz Arthur Calheiros; Pereira, Clara de Almeida; Fernandes, Izolda Moura; Mertens, Alessandra Brainer; Almeida, Milena Oliveira

    2014-05-21

    It is suggested that interleukin (IL)-13 and transforming growth factor (TGF)-beta play a role in the pulmonary vascular changes found in animal models of schistosomiasis. The aim of this study was to assess and compare the serum levels of total TGF-beta and IL-13 of patients with schistosomiasis with pulmonary arterial hypertension (PAH) and patients with schistosomiasis without PAH. 34 patients from the schistosomiasis outpatient clinic of the Hospital das Clinicas, Recife, Pernambuco, Brazil, without PAH assessed by echocardiography and 34 patients from the Reference Centre of Pulmonary Hypertension of Pronto Socorro Cardiológico de Pernambuco, Recife, Brazil with PAH, confirmed by right heart catheterization, were enrolled on the study. Both groups presented with schistosomal periportal fibrosis after abdominal ultrasound. Serum levels of TGF-beta1 and IL-13 were determined by ELISA. Student t test to independent samples, Mann-Whitney test to nonparametric variables, Pearson correlation test for correlation analyses and Fisher Chi-squared test to compare categorical analyses were used. The median value of TGF-beta1 was significantly higher in patients with PAH (22496.9 pg/ml, interquartile range [IR] 15936.7 - 32087.8) than in patients without PAH (13629.9 pg/ml, IR: 10192.2- 22193.8) (p = 0.006). There was no difference in the median value of IL-13 in the group with Sch-PAH compared to patients without Sch-PAH (p > 0.05). Our results suggest that TGF-beta possibly plays a role in the pathogenesis of schistosomiasis-associated PAH.

  17. Quality control of the slides by Kato-Katz method for the parasitological diagnosis of schistosomiasis infection by Schistosoma mansoni

    OpenAIRE

    Barbosa, Constança S.; Gomes, Elainne Christine S.; Marcelino, Jeann Marie R.; Cavalcante, Karina R. L. J.; Nascimento, Wheverton Ricardo C.

    2017-01-01

    ABSTRACT Introduction: Kato-Katz is a laboratory method recommended by the Brazilian Ministry of Health (BMH) and the World Health Organization (WHO) as the gold standard for the diagnosis of human infection by Schistosoma mansoni. The method has great clinical and epidemiological relevance because it allows the parasite load quantification of the infected patient by calculating the number of eggs per gram (EPG) of feces. This classification may also be used to estimate the intensity of infe...

  18. Schistosomiasis mansoni in Bananal (State of São Paulo, Brazil: I. Efficiency of diagnostic and treatment procedures

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    Horacio Manuel Santana Teles

    2002-10-01

    Full Text Available Bananal is an important focus of Schistosoma mansoni in the State of São Paulo. Accordingly, programmed active search for human cases, annual coproscopic surveys and treatment of infected cases were started in 1998, aiming at producing a sharp prevalence rate drop by the year 2000. S. mansoni eggs were searched for in two Kato-Katz slides per patient. Cases were followed up according to the routine of the local Family Health Program. In 1998, 130 samples out of 3,860 showed S. mansoni eggs; in 1999, 105 out of 3,550, and in 2000, 64 out of 3,528. Prevalence rates were 3.4%, 2.9%, and 1.8%, and average egg-counts 59, 64, and 79 eggs per gram of feces respectively. Prevalence rates decreased steadily after treatment, but persistently positive cases showed no significant decrease in parasite burdens. Egg count variation depended on sex and age bracket. Persistent residual cases admittedly preclude the eradication of this infection by only searching for and treating carriers. In addition, resistance to therapy and low sensitivity of fecal examinations, can not be ignored. Moderate to heavy worm burdens, frequently associated with hepatomegaly elsewhere, produced no serious cases in Bananal.

  19. Schistosomiasis mansoni in urban Northeast Brazil: influence of rainfall regime on the population dynamics of Biomphalaria sp.

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    Daniel Santos Oliveira

    2013-09-01

    Full Text Available Introduction Our objective was to evaluate the influence of rainfall regime on the population dynamics of Biomphalaria in a potential urban focus of schistosomiasis in Aracaju, Brazil, during 2009-2010. Methods Snails were collected monthly and were counted, measured and identified; the level of infection and fecal contamination at the sampling sites was determined; rainfall data were obtained. Results High levels of fecal contamination were observed, and the abundance of Biomphalaria glabrata increased during the rainy and post-rainy seasons. The snails' size was variable, and infected snails were identified independently of rainfall. Conclusions These results provide evidence of anthropogenic and climate interference in an urban focus of schistosomiasis in the Aracaju metropolitan area.

  20. Community's awareness about intestinal schistosomiasis and the ...

    African Journals Online (AJOL)

    BACKGROUND: Intestinal schistosomiasis caused by Schistosoma mansoni(S. mansoni) infection is a widely distributed disease in several localities of Ethiopia. However, very limited information is available on the level of community's awareness about the disease. The aim of this study was to assess community's ...

  1. Esquistossomose na área hiperendêmica de Taquarendi: I Infecção pelo Schistosoma mansoni e formas graves Schistosomiasis in hyperendemic area of Taquarendi: I- Schistosoma mansoni infection and severe clinical forms

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    José Carlos Bina

    2003-04-01

    Full Text Available A localidade de Taquarendi (Bahia está situada em zona de caatinga, porém com pequena faixa de terra irrigada, onde se encontram caramujos Biomphalaria glabrata. Dos 1.532 habitantes, 1.105 (72,1% submeteram-se ao exame clínico e, destes, 1.058 (95,7% fizeram exame parasitológico de fezes. A prevalência da esquistossomose foi de 73,1%, sendo que 16,2% destes eliminavam mais de 1.000 ovos por grama de fezes. O exame clínico mostrou que o lobo esquerdo do f��gado estava aumentado e/ou endurecido em 54% dos pacientes e o baço foi palpado em 21,8%. Foram classificados como hepatosplênicas 9,8% dos examinados e como portadores da forma hepatintestinal avançada 3,7%. Houve relação direta entre estas formas clínicas da doença e a intensidade da carga parasitária acima de 1.000 ovos de S. mansoni por grama de fezes.The study was carried out in Taquarendi (Bahia, a caatinga zone with a small irrigated strip of land, where Biomphalaria glabrata snails are found. From the 1,532 inhabitants, 1,105 (72.1% were submitted to clinical examination and 1058 out of them (95.7% made stool examinations. Prevalence of schistosomiasis was 73.1% and 16.2% of these patients eliminated more than 1,000 eggs per gram of stool. By clinical examination, the size and the consistency of the left liver lobe were increased in 54% of the individuals and the spleen was palpable in 21.8%. The diagnosis of hepatosplenomegaly and of the advanced hepatointestinal clinical form was made, respectively, in 9.8% and 3.7%. A direct relationship between such clinical forms of the disease and the worm load over 1.000 S. mansoni eggs/g of fezes was found.

  2. Estudo da camada de fibras nervosas da retina em pacientes com esquistossomose mansônica: análise com GDxTM Study of retinal nerve fiber layer in patients with schistosomiasis mansoni: analysis with GDX TM

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    Rodrigo Almeida Vieira Santos

    2006-12-01

    Full Text Available OBJETIVO: Estudar a camada de fibras nervosas da retina de portadores de esquistossomose mansônica hepatoesplênica. MÉTODOS: Foram submetidos ao exame com o GDx Scanning Laser System, 23 portadores de esquistossomose na forma hepatoesplênica que tinham sido submetidos, quando crianças, a esplenectomia, ligadura da veia gástrica esquerda e auto-implante de tecido esplênico no omento maior. Todos apresentaram pressão intra-ocular menor que 21 mmHg. No grupo controle foram estudados 23 indivíduos com idade e condição socioeconômico-geográfica similar, sem esquistossomose. RESULTADOS: Em apenas um paciente do grupo portador de esquistossomose foram observadas alterações em quatro parâmetros: superior nasal, média superior, média da espessura e número de fibra. Todos os indivíduos do grupo controle apresentaram GDx com parâmetros dentro da normalidade. CONCLUSÃO: No estudo realizado não foi encontrado diferença significante entre os dois grupos. Apenas um paciente mostrou redução da camada de fibras nervosas.PURPOSE: To study the retinal nerve fiber layer in young patients suffering from hepatosplenic schistosomiasis mansoni. METHODS: Twenty-three patients with hepatosplenic schistosomiasis mansoni who were submitted, when children, to splenectomy, ligature of the left gastric vein and auto-implantation of spleen tissue in the major omentum underwent GDx Scanning Laser System evaluations. All patients presented with intraocular pressure below 21 mmHg. RESULTS: Only one patient suffering from hepatosplenic schistosomiasis mansoni showed abnormalities on the GDx examination. There were no abnormalities on GDx examination in the control group. CONCLUSION: There was no significant difference between the two groups of this study. Only one patient showed retinal nerve fiber layer reduction.

  3. Efficacy of soluble glycoprotein fraction from Allium sativum purified by size exclusion chromatography on murine Schistosomiasis mansoni.

    Science.gov (United States)

    Aly, Ibrahim; Taher, Eman E; El-Sayed, Hoda; Mohammed, Faten A; ELnain, Gehan; Hamad, Rabab S; Bayoumy, Elsayed M

    2017-06-01

    In this work, the efficiency of crude MeOH extracts and soluble glycoprotein fraction of Allium sativum purified by size-exclusion chromatography (SEC) on parasitological, histopathological and some biochemical parameters in Schistosoma mansoni infected mice were investigated. Animals were infected by tail immersion with 100 cercariae/each mouse and divided into five groups in addition to the normal control. The results revealed a significant decrease in mean worm burden in all treated mice especially in the group treated with soluble glycoprotein fraction of A. sativum as compared to infected non-treated control with the disappearance of female worms. Administration of the studied extracts revealed remarkable amelioration in the levels of all the measured parameters in S. mansoni infected mice. In addition, treatment of mice with crude A. sativum MeOH extract and soluble glycoprotein fraction of A. sativum decreased significantly the activities of studied enzymes as compared to the infected untreated group. The highest degrees of enhancement in pathological changes was observed in the treated one with soluble glycoprotein fraction of A. sativum compared to the infected group represented by small sized, late fibro-cellular granuloma, the decrease in cellular constituents and degenerative changes in eggs. In conclusion, A. sativum treatment had effective schistosomicidal activities, through reduction of worm burden and tissue eggs, especially when it was given in purified glycoprotein fraction. Moreover, the soluble glycoprotein fraction of A. sativum largely modulates both the size and the number of granulomas. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Assessment of oltipraz in schistosomiasis mansoni clinical trial Avaliação do oltipraz na esquistossomose mansônica. Ensaio clínico

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    Naftale Katz

    1984-06-01

    Full Text Available Seventy three children (6-15 years and 75 adults (18-47 years with active schistosomiasis mansoni were treated with oltipraz. All cases had at least 100 eggs per gram of feces as determined by the Kato-Katz technique. Children and adults were divided in two groups receiving respectively 25 or 30 mg/kg, as a single oral dose. Clinical examination, laboratories tests (haemogram, urinalysis, hepatic and kidney functions tests, glycemia, cholesterol, triglicerides, lipoprotein — HLD and LDL and ECG were performed before, 3 or 7 days and 1 month after treatment. Parasitological control with 3 daily coprological examinations, was done on the 1st, 3rd j 6th month after drug administration. Giddiness, somnolence, headache, nausea, vomiting and abdominal distress were the most frequent side effects. Pain in the finger tips that need further investigations also occurred. No significant alteration in complementary tests were observed, whereas eosinophilia 1 month after treatment was detected, probably indicating worm death. The cure rate in children was 81.8% and 74.2% with 25 and 30 mg/kg respectively, and in adults 75.0% and 81.2% of the patients. No statistical significant difference was observed between cure rate and side effects at different dosages employed, neither between adults nor children. In all groups the percentage of egg reduction in feces in the non cured patients was higher than 96.0%. Further investigation with this new compound is necessary to accomplish the real value of oltipraz in the schistosomiasis chemotherapy.Setenta e três crianças (6 a 15 anos e 75 adultos (18-47 anos com esquistossomose mansoni foram tratados com oltipraz. O diagnóstico foi feito através do exame parasitológico quantitativo de Kato-Katz e só os pacientes com 100 ou mais ovos por grama de fezes foram admitidos no ensaio. Crianças e adultos foram divididos em dois grupos cada, os quais eram tratados com 25 ou 30 mg/kg em dose única oral. Exame cl

  5. Serum hyaluronan and collagen IV as non-invasive markers of liver fibrosis in patients from an endemic area for schistosomiasis mansoni: a field-based study in Brazil

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    Carolina Coimbra Marinho

    2010-07-01

    Full Text Available Non-invasive markers of fibrosis have been used to diagnose liver fibrosis in a variety of diseases. Hyaluronic acid (HA and collagen IV (C-IV levels were measured in the sera of patients from an endemic area for schistosomiasis in Brazil to diagnose and to rank the intensity of liver fibrosis. Seventy-nine adult patients with schistosomiasis, in the age range of 21-82 years (49 ± 13.4 were submitted to clinical and ultrasonographic examinations. Ultrasound was employed to diagnose and categorise liver fibrosis according to World Health Organization patterns. Serum HA and C-IV levels were measured using commercial ELISA kits. Ultrasound revealed six patients with intense liver fibrosis, 21 with moderate, 23 with light and 29 without. Serum HA was able to separate individuals with fibrosis from those without (p < 0.001 and light from intense fibrosis (p = 0.029, but C-IV was not (p = 0.692. The HA diagnostic accuracy for fibrosis was 0.89. The 115.4 ng/mL cut-off level diagnosed patients with fibrosis (sensitivity 0.98, specificity 0.64. HA correlated positively with portal hypertension. Periportal fibrosis (subjective evaluation, age and collateral circulation predicted HA increase. In conclusion, we propose that serum HA can be used to identify patients with liver fibrosis in an endemic area for schistosomiasis mansoni in Brazil.

  6. DETECTION OF IgM ANTIBODIES TO Schistosoma mansoni GUT-ASSOCIATED ANTIGENS FOR THE STUDY OF THE DYNAMICS OF SCHISTOSOMIASIS TRANSMISSION IN AN ENDEMIC AREA WITH LOW WORM BURDEN

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    KANAMURA Herminia Y.

    1998-01-01

    Full Text Available For a period of 2 years, five follow-up measures of prevalence and incidence rates were estimated in a prospective study of S. mansoni infection in a group of schoolchildren who were living in a rural area of the Municipality of Itariri (São Paulo, Brazil, where schistosomiasis is transmitted by Biomphalaria tenagophila. Infection was determined by the examination of three Kato-Katz stool slides, and the parasitological findings were analyzed in comparison to serological data. In the five surveys, carried out at 6-month intervals (March-April and September-October, the prevalences were, respectively, 8.6, 6.8, 9.9, 5.8 and 17.2% by the Kato-Katz, and 56.5, 52.6, 60.8, 53.5 and 70.1% by the immunofluorescence test (IFT. Geometric mean egg counts were low: 57.8, 33.0, 35.6, 47.3 and 40.9 eggs per gram of feces, respectively. Of the total of 299 schoolchildren, who submitted five blood samples at 6-month intervals, one for each survey, 40% were IFT-positive throughout the study, and 22% were IFT-negative in all five surveys. Seroconversion from IFT negative to positive, indicating newly acquired S. mansoni infection, was observed more frequently in surveys carried out during March-April (after Summer holidays, than during September-October. Seasonal trends were not statistically significant for detection of S. mansoni eggs in stool. The results indicate that the use of IgM-IFT is superior to parasitological methods for detection of incidence of S. mansoni infection in areas with low worm burden.

  7. Acute Schistosomiasis: Report on Five Singular Cases

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    Lambertucci JR

    1997-01-01

    Full Text Available The cases of five patients with unusual manifestations of acute schistosomiasis mansoni are described in this paper. One patient developed skin lesions, three displayed diverse lung involvement, and one presented pyogenic liver abscesses caused by Staphylococcus aureus

  8. Estudo clínico-epidemiológico da esquistossomose mansoni em escolares da Ilha, município de Arcos, MG (Brasil, 1983 Clinical-epidemiological study of schistosomiasis mansoni in school children of Ilha, Arcos County, Minas Gerais, Brazil, 1983

    Directory of Open Access Journals (Sweden)

    Mark Drew Crosland Guimarães

    1985-02-01

    Full Text Available Foi realizado um estudo clínico-epidemiológico da esquistossomose em escolares (6 - 14 anos da Ilha, em Minas Gerais (Brasil. Foram feitos exame parasitológico de fezes pelo método de KATO-KATZ e exame clínico em, respectivamente, 86,7 e 85,4% da população escolar. Foi realizado levantamento sócio-econômico e foram pesquisados os sinais e sintomas apresentados pelos pacientes e seus contatos com águas naturais. O índice de infecção pelo Schistosoma mansoni foi 32,7%, predominaram as baixas contagens de ovos nas fezes (89,0% dos pacientes eliminavam menos de 500 ovos/grama de fezes e o índide de esplenomegalia foi 7,7%. Os pacientes positivos (com ovos de S. mansoni nas fezes foram comparados aos negativos (sem ovos nas fezes e com intradermoreação negativa, verificando-se que a infecção pelo S. mansoni era significativamente mais freqüente entre os trabalhadores rurais, entre os que residiam em casas de pior qualidade e entre aqueles cujos chefes de família eram analfabetos. Constituíram os maiores fatores de risco para a infecção pelo S. mansoni nesta área: a ter contatos com águas naturais para trabalhar na lavoura (Odds Ratio = 18,08; b ter contatos diários com águas naturais (OR = 13,82 e c ter contatos com águas naturais para pescar, nadar e/ou brincar (OR = 7,75 e 5,51, respectivamente. Os autores levantam a hipótese de que a transmissão da esquistossomose nesta localidade não ocorre no peridomicílio, mas sim nas lagoas próximas à Ilha e nas plantações agrícolas, provavelmente nas culturas de arroz de várzea.A schistosomiasis mansoni clinical-epidemiological study was carried out among school children (6-14 years old of the Ilha community, Minas Gerais. Stool examination, using the KATO-KATZ method, and clinical examination were performed on 86.7 and 85.4%, respectively, of the population studied. The signs and symptoms presented by the patients as well as their contacts with untreated water were

  9. Long term study on the effect of mollusciciding with niclosamide in stream habitats on the transmission of schistosomiasis mansoni after community-based chemotherapy in Makueni District, Kenya

    DEFF Research Database (Denmark)

    Kariuki, Henry C.; Madsen, Henry; Ouma, John H.

    2013-01-01

    BACKGROUND: Schistosoma mansoni infection is a persistent public health problem in many Kenyan communities. Although praziquantel is available, re-infection after chemotherapy treatment is inevitable, especially among children. Chemotherapy followed by intermittent mollusciciding of habitats of B...

  10. Akut schistosomiasis (Katayama-feber)

    DEFF Research Database (Denmark)

    Jensen, T; Rønne-Rasmussen, J O; Bygbjerg, Ib Christian

    1995-01-01

    Acute schistosomiasis (Katayama fever) may present with a broad spectrum of symptoms three to six weeks after primary infection by Schistosoma (S) mansoni, S. japonicum or, more rarely, S. haematobium. The acute phase of schistosomiasis is frequently confused with other feverish diseases. It occurs...... almost exclusively in nonimmune visitors to endemic areas. We describe seven cases of acute S. mansoni infection. The pathogenesis, clinical features, diagnosis and treatment are briefly discussed. Katayama fever should be considered in patients returning from endemic areas with fever and eosinophilia...

  11. Estudo epidemiológico da esquistossomose mansônica em áreas de irrigação do Nordeste brasileiro Epidemiological study on mansoni schistosomiasis in irrigation areas of Northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Amaury D. Coutinho

    1992-09-01

    Full Text Available É mundialmente reconhecida a importância das áreas de irrigação na disseminação da esquistossomose. O presente estudo foi desenvolvido no período de outubro de 1986 a dezembro de 1987 em 23 perímetros de irrigação do Nordeste semi-árido. A análise sócio-econômica-sanitária mostrou vários aspectos de interesse epidemiológico, salientando-se a presença de trabalhadores flutuantes originários de áreas endêmicas da parasitose e vivendo em más condições sanitárias nos lotes de irrigação. O estudo coprológico indicou os seguintes resultados: de 10.279 indivíduos examinados (82% da população somente 3 (três casos apresentaram-se positivos para S. mansoni. O estudo malacológico mostrou a presença exclusiva da Biomphalaria straminea em 17.188 amostras coletadas. Somente em um dos perímetros (São Gonçalo, Souza, PB foi constatada a infecção esquistossomótica ativa em 17 caramujos. Esses resultados indicam que as áreas de irrigação estudadas não constituem, no momento, problema relevante de transmissão da esquistossomose. Os autores consideram, porém, necessária uma permanente vigilância epidemiológica em todas as áreas de irrigação do Nordeste.It is acknowledged throughout the world that irrigation is very important in the dissemination of schistosomiasis. The present study, involving 23 irrigation projects in the semi-arid region of five northeastern states of Brazil, was conducted during the period of October 1986 to December 1987. Socio-economic-sanitary analysis identified a number of aspects of epidemiological importance, mainly the presence of migrant farm workers, coming from endemic areas of schistosomiasis and living in poor sanitary conditions in the irrigation areas. Parasitological exams of stool samples indicated that, out of 10,229 individuals examined (82% of the population, only three were S. mansoni positive. Malacological studies identified Biomphalaria straminea as the only species

  12. REVIEW ARTICLE Schistosomiasis and malignancy

    African Journals Online (AJOL)

    and colon carcinoma reviewed. SAfrMedJ1994; 84: 211-215. It has been estimated that over 250 million ... Historical background. Theodor Bilharz first found adult worms of the trema- tode, now known ..... A raised incidence of colorectal cancer in association with schistosomiasis due to S. mansoni has not been detected in ...

  13. Human schistosomiasis in Ngamiland, Botswana

    DEFF Research Database (Denmark)

    Andersen, L; Magnussen, Pascal; Wouters, J S

    1985-01-01

    To reassess the schistosomiasis problem in Ngamiland and especially in Maun area 552 primary school children and 213 adult labourers were examined with urinalysis and rectal snip. Of the pupils 80.3% were found positive for S. mansoni and 1.4% for S. haematobium; of the labourers 35.7% were...

  14. Schistosoma mansoni Infection in Finchaa Sugar Estate: Public ...

    African Journals Online (AJOL)

    The survey of Schistosoma mansoni (S. mansoni) in Finchaa Sugar Estate, Western Ethiopia, was conducted to investigate the prevalence and health problems of schistosomiasis with some of the risk factors. The examination was undertaken based on the analysis of retrospective clinical data from the health center and a ...

  15. Morbidade da esquistossomose mansoni no Brasil: II - Estudo em quatro áreas de campo nos Estados de Minas Gerais, Sergipe e Paraíba Morbidity of schistosomiasis mansoni in Brazil: II - Study in 4 field areas in the states of Minas Gerais, Sergipe and Paraiba

    Directory of Open Access Journals (Sweden)

    J. Rodrigues Coura

    1983-03-01

    Full Text Available Os autores fazem um estudo comparativo sobre a morbidade da esquistossomose mansoni em 4 áreas de campo no Brasil, duas na região Sudeste (Capitão Andrade, município de Inhomi e Padre Paraíso, ambas no Estado de Minas Gerais e duas outras na região nordeste (Riachuelo, no Estado de Sergipe e Alhandra, no Estado da Paraíba. A população total estudada nas 4 áreas foi de 4.870 pessoas, das quais 1.369 em Capitão Andrade (área 1, 850 em Riachuelo (área 2, 1.736 em Padre Paraíso (área 3 e 915 em alhandra (área 4. Na área 1, com uma população de 1.480 habitantes, foi tentado um estudo de toda a pupulação. Nas áreas 2, 3 e 4, devido ao grande número de habitantes, foi estudada uma amostra sistemática por conglomerado de aproximadamente 25% da população (grupamento familiar de uma em cada 4 residências. O estudo constou e uma avaliação das condições econômicas e sanitárias da população, do seu contacto com os focos locais de transmissão da esquistossomose, dos índices e intensidade da infecção pelo S. mansoni e das relações da carga parasitária com as diversas formas clínicas da doença em diferentes grupos etários. Paralelamente, foi feito um estudo dos hospedeiros intermediários de cada área e dos seus índices de infecção com cercárias de S. mansoni. Demonstrou-se uma prevalência de 60,8, 50,5, 63,1 e 46,6% de infecção ativa pelo S. mansoni para as áreas 1, 2, 3 e 4, com a mediana de eliminação de ovos de 207, 77,6, 391 e 211 respectivamente. Verificou-se, ainda, nas áreas da região Sudeste um aumento mais tardio dos parâmetros mencionados. Outras correlações com grupos etários, sexo, cor dos pacientes, bem como os índices de infecção dos planorbídeos com a forma clínica da doença foram feitas.The authors have carried out a comparative study on the morbidity of schistosomiasis mansoni in four field areas of Brazil, two in the Southeast Region (Capitão Andrade, Itanhomi Municipality

  16. human intestinal schistosomiasis in communities living near three ...

    African Journals Online (AJOL)

    Abrham

    2011-07-02

    Jul 2, 2011 ... snails (Biomphalaria pfeifferi and. Biomphalaria sudanica) are responsible for the transmission of S. mansoni in the country (6). The former is the most ..... G, VanLieshout L. Schistosomiasis mansoni in school attenders and non- attenders in Northwest Ethiopia. Ethiop J. Health Dev 2001; 15(2):117-23. 17.

  17. Atividade antiparasitária do artemether na esquistossomose mansônica experimental Antischistosomal activity of artemether in experimental Schistosomiasis mansoni

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    Susana Zevallos Lescano

    2004-02-01

    Full Text Available OBJETIVO: Avaliar o efeito da administração intramuscular de artemether a camundongos infectados experimentalmente por Schistosoma mansoni no momento da infecção, durante a maturação dos esquistossômulos e após iniciada a oviposição. MÉTODOS: Oitenta camundongos Balb/c, fêmeas adultas, foram divididos em oito grupos com 10 animais cada. Sete grupos foram infectados por S. mansoni empregando-se 60 cercárias para cada animal, inoculadas por via subcutânea; o grupo restante foi mantido sem infecção. Entre os sete grupos infectados, seis foram tratados com artemether, segundo o seguinte esquema: três grupos receberam dose correspondente a 100 mg/kg no dia 0, 20 ou 60 após inoculação das cercárias; os demais receberam 50 mg/kg de artemether, no mesmo período que os lotes anteriores. Da 9ª, 10ª e 11ª semanas após infecção os camundongos infectados por S. mansoni foram submetidos a exames de fezes pela técnica de Kato-Katz. No 80º dia do experimento, os animais sobreviventes foram sacrificados e submetidos à perfusão do sistema porta para recuperação de vermes. Determinaram-se, nessa ocasião, os pesos corporal, hepático e esplênico de cada animal. RESULTADOS: Observou-se queda na oviposição e no número de vermes recuperados entre os camundongos tratados com artemether (50 ou 100 mg/kg no 20º dia após infecção. A diminuição do número de vermes foi mais expressiva no caso de fêmeas de S. mansoni. Verificou-se, ainda, diminuição significativa nos pesos hepático e esplênico entre os animais tratados com 50 e 100 mg/kg de artemether no 20º dia e também entre os que receberam a droga na dose de 50 mg/kg 60 dias após infecção. CONCLUSÕES: Ficou evidenciada a atividade anti-Schistosoma do artemether, mesmo ao se empregar dose correspondente a 50 mg/kg, quando a droga foi administrada durante o período de maturação dos esquistossômulos no sistema porta do hospedeiro vertebrado.OBJECTIVE: To evaluate

  18. Nutrition and acute schistosomiasis

    Directory of Open Access Journals (Sweden)

    Eridan M. Coutinho

    1992-01-01

    Full Text Available In northeast Brazil, nutritional deficiency diseases and schistosomiasis mansoni overlap. An experimental model, wich reproduces the marasmatic clinical form of protein-energy malnutrition, was developed in this laboratory to study these interactions. Albino Swiss mice were fed with a food association ingested usually by human populations in northeast Brazil. This diet (Regional Basic Diet - RBD has negative effects on the growth, food intake and protein utilization in infected mice (acute phase of murine schistosomiasis. Nitrogen balance studies have also shown that infection with Schistosoma mansoni has apparently no effect on protein intestinal absorption in well nourished mice. However, the lowest absorption ratios have been detected among RBD - fed infected animals, suggesting that suprerimposed schistosome infection aggravated the nutritional status of the undernourished host. The serum proteins electrophoretic pattern, as far as albumins are concerned, is quite similar for non-infected undernourished and infected well-fed animals. So, the significance of albumins as a biochemical indicator of the nutritional status of human populations residing in endemic foci of Manson's schistosomiasis, is discussable.

  19. Schistosomiasis mansoni in an area of low transmission: II. Risk factors for infection Esquistossomose mansônica em área de baixa transmissão: II. Fatores de risco para infecção

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    Oswaldo Marçal Júnior

    1993-08-01

    Full Text Available Risk factors for Schistosoma mansoni infection were identified using a 1:1 matched case-control design. The work was conducted in the municipality of Pedro de Toledo, São Paulo State, Brazil, an area where the snail host is Biomphalaria tenagophila. Information on water contact patterns, knowledge, attitudes and pratices (kap, socioeconomic and sanitary conditions were obtained by mean of questionnaires. The crude odds ratio estimates and the adjusted odds ratio estimates using the logistic regression model are presented. Most of the examined individuals admitted recent water contacts (90.6% of the cases. The most frequent reason for contact was swimming, playing and fishing and the preferential site of contact was the river. According to the logistic regression technique, the main risk factors for infection were: a water contact through swimming, playing and fishing; b fording; c bad hygiene. We concluded that recreational activities are the main reasons for schistosomiasis transmission in Pedro de Toledo and leisure alternatives should be offered to the local population.A partir de um estudo de caso-controle por pareamento (1:1 foram determinados os fatores de risco para infecção por Schistosoma mansoni. O trabalho foi desenvolvido no município de Pedro de Toledo, São Paulo, Brasil, área onde Biomphalaria tenagophila é o hospedeiro intermediário. Por meio de questionários foram obtidas informações sobre o padrão de contato com águas naturais; percepção da doença e condições sanitárias e socio-econômicas. Os fatores de risco foram estimados individualmente e através de modelo logístico. A maioria dos pesquisados admitiu contatos recentes com águas naturais (90,6% dos casos. O motivo mais freqüente para estes contatos foi nadar, brincar e pescar. O rio representou o principal local de contato com águas naturais. De acordo com a técnica de regressão logística, os principais fatores de risco foram: a contato com

  20. Analysis of complex patterns of human exposure and immunity to Schistosomiasis mansoni: the influence of age, sex, ethnicity and IgE.

    Directory of Open Access Journals (Sweden)

    Angela Pinot de Moira

    2010-09-01

    Full Text Available Numerous factors may influence Schistosoma infection intensity and prevalence within endemic communities, including exposure-related factors such as local environment and behaviour, and factors relating to susceptibility to infection such as immunology and genetics. While animal studies performed in the laboratory can be tightly controlled, human populations are highly heterogeneous, varying according to demographic characteristics, genetic background and exposure to infection. The heterogeneous nature of human water contact behaviour in particular makes it difficult to distinguish between a lack of cercarial exposure and reduced susceptibility to infection as the cause for low levels of infection in the field.In this study we investigate risk factors for Schistosoma mansoni infection in a rural Ugandan fishing community receiving treatment as part of a multi-disciplinary longitudinal reinfection study. More specifically, we examine the influence that age, sex and ethnic background have on susceptibility to reinfection after anti-helminth drug treatment, but use individual estimates of cercarial exposure and multivariable methods in an attempt to remove noise created by environmental and behavioural heterogeneities. We then investigate whether schistosome-specific IgE immune responses could account for any remaining variations in susceptibility to reinfection. Our findings suggest that observed ethnic- and sex-related variations in S. mansoni reinfection were due to variations in cercarial exposure, as opposed to biological differences in susceptibility to infection. Age-related differences in reinfection were not explained by exposure, however, and appeared linked to the balance of IgE and IgG(4 to the tegumental antigen SmTAL1 (formerly Sm22.6, which itself was significantly related to resistance to reinfection.This study highlights the benefit of taking a multidisciplinary approach in complex field settings; it allows the ecology of a

  1. Comportamento experimental de amostras de Schistosoma mansoni em relação às formas clínicas de esquistossomose: I. Estudo em camundongos Experimental behavior of samples of Schistosoma mansoni in relation to clinical forms of schistosomiasis: I. Study in mice

    Directory of Open Access Journals (Sweden)

    Mario José da Conceição

    1986-03-01

    ção da doença.Twenty isolates of Schistosoma mansoni were obtained from patients, all males 13 to 30 years old, autochtonous from the Village of Capitão Andrade, municipality of Itanhomi, state of Minas gerais, where an evolutive study of Manson's schistosomiasis is being performed since 1973. The isolates came from six patients with schistosome-infections (type I0, six with the hepato-instestinal form (type Ii, and eight with the hepaoesplenic form (type III. Each isolate was inoculated in mice divided in three groups of 16, exposed to 25, 50 and 100 cercariae, respectively. Controls were 12 uninfected mice. After 90 days adult worms were recovered from the portal by perfusion, from four mice of each experimental groups. Mice dying at various intervals and half of the rest f mice in each group sacrificed on the 90th and the 180th days were studied according to the following parameters: 1 weight of liver, spleen, lung and instestine; 2 egg count in the small intestine (proximal and medial and large intestine (distal. The average numbers of worms obtained by perfusion from groups I, II and III were 21.9%, 22% and 17.8% respectively. The average natural mortality rates of mice submitted to infection with 25,50 and 100 cercariae were, respectively, 12.4%, 23.2% and 40.2% for group I,4.7%, 19.5% and 22.2% for group II and 11.4%, 29.5% and 41.6% for group III, being therefore proportional to the inocula. The weight of the organs of the infected animals and the number of S. mansoni eggs was always proportional to the inoculum and the highest number of eggs were found in the median and proximal portion of the intestines in all three groups. The conclusion was the following: there was no correlation between the clinical forms of schistosomiasis and the behaviour of the isolates of S. mansoni in mice, the parasitological alternations being proportional to the inoculum used and the duration of the infection.

  2. Morbidade da esquistossomose mansoni no Brasil: III Estudo evolutivo em uma área endêmica no período de dez anos Morbidity of schistosomiasis mansoni in Brazil. III.Evolutive study in an endemic area in a period of 10 years

    Directory of Open Access Journals (Sweden)

    José Rodrigues Coura

    1984-12-01

    conta própria.Four cross sectional studies on morbidity of schistosomiasis mansoni were carried out respectively in 1973, 1974, 1979 and 1983 in the Village of Capitão Andrade, District of Itanhomi, State of Minas Gerais, Brazil, through clinical and fecal examination of the population. In addition a comparison was made of the dinamic and infection rate of the snails and the man-water contact between 1973-1974. The present study compares the prevalence of the human infection by S. mansoni and the evolutive pattern of the disease in the area from 1973 to 1983. besides 190 persons infected with S. mansoni and 134 non-infected, were followed-up during this period. The infection rate was 60.8% among 1,234 persons examined in 1973,, decreasing to 36.2% of the 1,269 examined in 1983. However, the intense migration of the population in the area and the specific treatment of 7% of person by their own decision may be partially responsible for this reduction. Although there was a decrease of more than 50% in the mean egg output of S. mansoni, there was no change in the morbility of the disease and in the proportion of the different clinical forms. The incidence of S. mansoni infection among 134 persons followed-up during the ten years was 40.3% (annual average of 4%, with 61.9% in males. The incidence of the clinical forms was 51.8% for type I (intestinal form, 38.9% for type II (hepatointestinal and 9.3% for type III (hepatoesplenic. The clinical evolutive pattern of 190 patients followed-up during the mentioned period showed that 75.3% had no change, 12.1% deteriored and 12,6% improved. two thirds of those which improved (8.4% had receveid specific treatment.

  3. Studies on heterologous immunity in schistosomiasis

    Science.gov (United States)

    Preston, J. M.; Nelson, G. S.; Saeed, A. A.

    1972-01-01

    Previous studies have shown that when cattle are exposed to cercariae of Schistosoma mansoni they develop considerable resistance to subsequent challenge with S. mattheei. The present study showed that when sheep are immunized with S. mansoni cercariae they too develop a marked resistance to subsequent challenge with S. mattheei. A small proportion of the immunizing cercariae reached maturity and a few viable S. mansoni eggs were found in the faeces of the sheep. The results of this experiment provide further evidence that heterologous immunity may be of significance in limiting the severity of schistosomiasis in both man and domestic animals in areas where animal and human schistosomes occur together. PMID:4540678

  4. Sociocultural aspects of schistosomiasis mansoni in an endemic area in Minas Gerais, Brazil Aspectos sócio-culturais da esquistossomose mansoni em área endêmica de Minas Gerais, Brasil

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    Andréa Gazzinelli

    1998-10-01

    Full Text Available A study to determine the sociocultural factors influencing knowledge, attitudes, and practices of individuals from a small community toward Schistosoma mansoni infection was carried out in an endemic area in the State of Minas Gerais, Brazil. The study used qualitative approaches to collect data from school-aged children and teachers. Specific findings were that the individuals interviewed were aware of the disease, but also held inaccurate popular beliefs about transmission. Misconceptions coexisted with accurate knowledge both in children and teachers. The disease was not seen as a major health problem and did not affect their activities since it did not cause severe symptoms in most of the individuals. Although the majority of the participants related transmission to water and lack of sanitation, they did not take any preventive measures since their subsistence is highly dependent on irrigation, farming, fishing, and other essential work that is directly related to water activities. The authors discuss the development of a health education program based on the knowledge and perception of individuals about the disease and its determinants as being important for the context and behavioral change.Este estudo foi realizado em área endêmica do Estado de Minas Gerais, Brasil, com o objetivo de determinar os fatores sócio-culturais que influenciam o conhecimento, as atitudes e práticas dos indivíduos da comunidade em relação a esquistossomose mansoni. Os resultados mostraram que tanto crianças quanto professores conhecem a doença e possuem concepções corretas e incorretas sobre a transmissão. A doença não é vista como um problema importante de saúde pública e não afeta as atividades pelo fato de não causar sintomas graves na maior parte da população. Apesar da maioria dos entrevistados relacionar a transmissão da doença à água e falta de saneamento básico, não utiliza nenhuma medida preventiva para evitar a infec

  5. Immunity to schistosomiasis mansoni in guinea-pigs vaccinated with radiation-attenuated cercariae. Humoral responses against skin-stage schistosomula

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, J.R.; McLaren, D.J.

    1987-02-01

    The anti-schistosomular humoral responses of guinea-pigs vaccinated with radiation-attenuated cercariae of Schistosoma mansoni have been investigated in vitro. The sera of vaccinated animals contain schistosomulicidal complement-fixing antibodies which peak in titre at week 5 after vaccination and predominantly consist of IgG/sub 2/ and IgM antibodies. The ability of the serum to arm macrophages from normal animals to bind to schistosomula, also peaks in titre at week 5 and is associated with IgG/sub 2/ antibodies. Basophils from normal animals can be sensitized in vitro by vaccine serum to degranulate in the presence of schistosomular antigens. This anaphylactic antibody activity is associated with IgG/sub 1/ but not IgE antibodies, and peaks in titre at week 10. Three antigens (14 kD, 20 kD and 43 kD) are specifically and transiently detected by vaccine serum on Western blots of schistosomular proteins; these antigens are first discernible at week 4, but were virtually undetectable at week 12.

  6. Immunohistochemical expression of oestrogen and progesterone receptors during experimental acute and chronic murine Schistosomiasis mansoni Expressão imunohistoquímica de receptores para estrogênio e progesterona nas fases aguda e crônica da esquistossomose mansônica experimental em camundongos

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    Fawzia Ahmed Habib

    2010-10-01

    Full Text Available INTRODUCTION: The responsibility of Schistosoma mansoni in female infertility is still controversial. This study was conducted to evaluate the effect of acute and chronic schistosomiasis mansoni infection on the endometrium using immunohistochemical analysis of uterine hormone receptor expression. METHODS: Twenty-four nonpregnant swiss albino mice were divided into three groups: control, noninfected; acute; and chronic Schistosoma mansoni infection. Histological sections of uterine specimens were examined by light microscope with an image analyzing system to detect structural histological, estrogen receptor (ER and progesterone receptor (PR expression in the endometrium. RESULTS: No secretory phase was detected in the endometrium in acute and chronic Schistosoma infection. Hormone receptor expression (ER and PR showed statistically significant differences among the groups (pINTRODUÇÃO: A responsabilidade do Schistosoma mansoni em esterilidade feminina é ainda controversa. Este estudo é conduzido para avaliar o efeito da esquistossomose mansoni aguda e crônica no endométrio usando análise de imuno-histoquímíca da expressão de receptor hormonal uterina. MÉTODOS: Vinte e quatro camundongos fêmeas albinas suíças não grávidas foram divididas em 3 grupos (controle não-infectado, grupos agudos e crônicos infeccionados com Schistosoma mansoni. As seções histológicas de espécimes uterinos foram examinadas por microscópio leve com imagem, analisando sistema para detectar no endométrio expressões histológicas estruturais, receptor de estrogênio (ER e receptor de progesterona (PR. RESULTADOS: Nenhuma fase secretora foi detectada no endométrio com infecção aguda e crônica de Schistosoma. A expressão hormonal de receptor (ER e PR mostrou diferenças estatisticamente significantes entre grupos diferentes (p<0,05 com baixa significativa hormonal de ER com infecção crônica (comparado com controle proliferativo, controle secret

  7. Epidemiological survey on schistosomiasis caused by Schistosoma ...

    African Journals Online (AJOL)

    Objective: To assess the current state of schistosomiasis (Schistosoma haematobium and Schistosoma mansoni) in Taïbong Sub Division, in Mayo-Kani Division, an epidemiological survey was conducted from September to November 2014 in four government primary schools, to determine the prevalence of these human ...

  8. Assessment of schistosomiasis and intestinal helminths following ...

    African Journals Online (AJOL)

    The following intestinal parasites were found in stools with various prevalence: Schistosoma mansoni 0.1% (95% CI: 0% - 0.3%) and Ancylostoma duodenale 0.1% (95% CI: 0% - 0.2%). The prevalence of urinary schistosomiasis in the Centre and Plateau Central regions had been greatly reduced from the previous level in ...

  9. Index of Potential Contamination for Intestinal Schistosomiasis ...

    African Journals Online (AJOL)

    Bheema

    deployedto assess associated risk factors among infected children. Out of the examined children, ... health problem, and to a great extent children of 10-14 years age group were responsible in the transmission and ... Although several epidemiological studies for intestinal schistosomiasis due to S. mansoni infection were ...

  10. HIV and schistosomiasis : studies in Tanzania

    NARCIS (Netherlands)

    Downs, J.A.

    2016-01-01

    Schistosomiasis is a helminthic worm infection that affects 260 million people worldwide, 90% of whom live in sub-Saharan Africa. In Tanzania, where the research in this thesis was conducted, two species of schistosomes are highly endemic (Schistosoma haematobium and S. mansoni), with more than 50%

  11. Stool examination and rectal biopsy in the diagnosis and evaluation of therapy of schistosomiasis mansoni Exame de fezes e biópsia retal no diagnóstico e controle de cura da esquistossomose mansoni

    Directory of Open Access Journals (Sweden)

    Ana Lúcia Teles Rabello

    1992-12-01

    Full Text Available From each of a group of 217 adult males selected through enzyme-immunoassay or skin-test (Group A, six stool samples were examined by both the Lutz/Hoffman, Pons & Janer (Lutz/HPJ and Kato/Katz methods. In addition, one oogram of the rectal mucosa was performed. By these methods, schistosomiasis was detected in 44.7%, 47.5% and 40.1% of the individuals respectively. To evaluate the methods in the assessment of cure, the last 40 patients from group A, treated with a single oral dose of oxamniquine at 15 mg/kg were followed up for six months (Group B. The criteria for parasitological cure included three stool examinations by Kato/Katz and Lutz/HPJ methods, one, three and six months post-treatment and a rectal biopsy between the fourth and sixth months post-treatment. The examinations were negative in 87.5%, 90% and 95% of the patients, respectively. The efficacy of oxamniquine was 82.5% when the three methods were considered together and there was no statistically significant difference between the sensitivity of the individual methods.Em um grupo de 217 adultos do sexo masculino selecionados através de ELISA ou intradermoreação, realizaram-se seis exames de fezes pelos métodos de Lutz/Hoffman, Pons e Janer (Lutz/HPJ e Kato/Katz e um oograma da mucosa retal, observando-se positividade em 44,7%, 47,5% e 40,1%, respectivamente. A análise comparativa dos resultados mostrou: 1 aumento da sensibilidade de ambos os métodos de exames de fezes até a terceira amostra examinada; 2 maior sensibilidade da biópsia retal quando comparada ao exame de uma única amostra fecal pelos métodos de Lutz/HPJ ou Kato/Katz; 3 igual sensibilidade pelo exame de duas a cinco amostras fecais pelo método de Kato/Katz ou duas a seis amostras pelo método de Lutz/HPJ e a biópsia retal; 4 sensibilidade superior de seis amostras fecais pelo método de Kato/Katz, quando comparado à biópsia retal; 5 igual sensibilidade entre o mesmo número de amostras examinadas pelos

  12. Epidemiology of Schistosomiasis in Egypt: Travel through Time: Review

    Directory of Open Access Journals (Sweden)

    Rashida M.R. Barakat

    2013-09-01

    Full Text Available Schistosomiasis is a parasitic disease caused by blood flukes (Trematodes of the genus Schistosoma (S.. It is well documented that schistosomiasis haematobium was endemic in Ancient Egypt. Infection was diagnosed in mummies 3000, 4000 and 5000 years old. Scott was the first to describe the pattern of schistosomiasis infection in Egypt. Schistosomiasis haematobium was highly prevalent (60% both in the Nile Delta and Nile Valley South of Cairo in districts of perennial irrigation while it was low (6% in districts of basin irrigation. Schistosoma mansoni infected 60% of the population in the Northern and Eastern parts of the Nile Delta and only 6% in the Southern part. Neither S. mansoni cases nor its snail intermediate host were found in the Nile Valley South of Cairo. The building of the Aswan High Dam -which was completed in 1967 – did not cause any increase in schistosomiasis prevalence. In 1990, a study conducted in nine governorates of Egypt confirmed the change in the pattern of schistosomiasis transmission in the Delta. There was an overall reduction in S. mansoni prevalence while Schistosoma haematobium had continued to disappear. In Middle and Upper Egypt there was consistent reduction in the prevalence of S. haematobium except in Sohag, Qena, and Aswan governorates. However, foci of S. mansoni were detected in Giza, Fayoum, Menya and Assiut. All schistosomiasis control projects implemented in Egypt from 1953 to 1985 adopted the strategy of transmission control and were based mainly on snail control supplemented by anti-bilharzial chemotherapy. In 1997, the National Schistosomiasis Control Program (NSCP was launched in the Nile Delta. It adopted morbidity control strategy with Praziquantel mass treatment as the main component. In 1996, before the NSCP, 168 villages had S. mansoni prevalence >30%, 324 villages 20–30% and 654 villages 10–20%. By the end of 2010, in the whole country only 29 villages had prevalence >3% and none had

  13. Schistosoma mansoni: a rare cause of tubal infection

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    CA Faria

    Full Text Available S. haematobium is an important cause of urinary schistosomiasis, and symptomatic female genital infection is a common gynecological finding in areas where S. haematobium is prevalent. On the other hand, genital manifestations of intestinal schistosomas as S. mansoni are not frequent or are misdiagnosed. A case of a 40-year-old woman with abnormal uterine bleeding and asymptomatic tubal infection by S. mansoni identified in histological examination is presented.

  14. Descrição de um novo foco endêmico de esquistossomose mansônica no Estado de São Paulo, Brasil The description of a new endemic focus of schistosomiasis mansoni in the state of S. Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Afonso Dinis Costa Passos

    1979-12-01

    Full Text Available Foi descrito novo foco endêmico de esquistossomose mansônica situado na Cidade de Bebedouro, Estado de São Paulo, Brasil. Foram analisados 221 casos diagnosticados da doença segundo a idade, sexo e origem (autóctone ou não, bem como foram discutidos os fatores envolvidos no aparecimento do foco, alertando-se para a necessidade de medidas de controle.A new endemic focus of schistosomiasis mansoni in the town of Bebedouro, S. Paulo, Brazil, is described. Two hundred and twenty-one cases are analyzed according to sex, age, and origin (autochthonous or not, the factors involved in the emergence of the focus are discussed and the necessity for control measure is emphasized.

  15. Morbidade da esquistossomose mansoni no Brasil. I - Estudo de 4.652 casos observados no Rio de Janeiro de 1960 a 1979 Morbidity of schistosomiasis mansoni in Brazil. I - Study of 4652 cases observed in Rio de Janeiro from 1960 to 1979

    Directory of Open Access Journals (Sweden)

    J. Rodrigues Coura

    1982-03-01

    Full Text Available No período de vinte anos (1960-1979, os autores observaram na Clínica de Doenças Infecciosas e Parasitárias da Faculdade de Medicina da Universidade Federal do Rio de Janeiro, sediada no Pavilhão Carlos Chagas do Hospital São Francisco de Assis, 4.652 casos de esquistossomose mansoni procedentes de 18 Estados do Brasil. Entre os casos observados 87,18% eram da forma hepatointestinal e 12,82% da forma hepatoesplênica entre os quais 30 tinham a forma pulmonar associada. Adicionalmente 30 casos da forma aguda ou toxémica foram estudados no mesmo Serviço, em famílias residentes no Rio de Janeiro. Além da observação clínica e do estudo epidemiológico incluindo o perfil migratório de cada caso e da casuística como um todo, foram realizados exames complementares como hemograma, mielograma, dosagem de transaminases, provas de função hepática, eletroforese de proteínas séricas, biópsia hepática, radiografias de tórax e de esôfago, esplenoportografia, eletrocardiograma e estudos hemodinâmicos do sistema porta, do coração e da artéria pulmonar em grupos de pacientes selecionados.A study of 4.652 schistosomiasis mansoni patients from 18 different States in Brazil, indicates a general picture of the morbidity of this disease in the country. Patients migrants (4.652 from different States were studied in the Department of Tropical Medicine of Federal University of Rio de Janeiro, between 1960 and 1979, with the following parameters: selected by a positive stool examination (sedimentation technique, clinical and epidemiological evaluation to determine the clinical form, migration pattern, age, sex and race. A routine chest X ray, E. C. G., haematologic and biochemistry tests, were performed. In a selected group of hepatosplenic cases a liver, biopsy, splenoportography and a portal hemodynamic study were done. Although some regional, familial, racial and/or individual differences in morbidity have been observed, the intensity of the

  16. A next-generation proteome array for Schistosoma mansoni.

    Science.gov (United States)

    de Assis, Rafael Ramiro; Ludolf, Fernanda; Nakajima, Rie; Jasinskas, Al; Oliveira, Guilherme C; Felgner, Philip L; Gaze, Soraya T; Loukas, Alex; LoVerde, Philip T; Bethony, Jeffrey M; Correa-Oliveira, Rodrigo; Calzavara-Silva, Carlos E

    2016-06-01

    A proteome microarray consisting of 992 Schistosoma mansoni proteins was produced and screened with sera to determine antibody signatures indicative of the clinical stages of schistosomiasis and the identification of subunit vaccine candidates. Herein, we describe the methods used to derive the gene list for this array (representing approximately 10% of the predicted S. mansoni proteome). We also probed a pilot version of the microarray with sera from individuals either acutely or chronically infected with S. mansoni from endemic areas in Brazil and sera from individuals resident outside the endemic area (USA) to determine if the array is functional and informative. Copyright © 2016. Published by Elsevier Ltd.

  17. Computational Vaccinology: An Important Strategy to Discover New Potential S. mansoni Vaccine Candidates

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    Carina S. Pinheiro

    2011-01-01

    Full Text Available The flatworm Schistosoma mansoni is a blood fluke parasite that causes schistosomiasis, a debilitating disease that occurs throughout the developing world. Current schistosomiasis control strategies are mainly based on chemotherapy, but many researchers believe that the best long-term strategy to control schistosomiasis is through immunization with an antischistosomiasis vaccine combined with drug treatment. Several papers on Schistosoma mansoni vaccine and drug development have been published in the past few years, representing an important field of study. The advent of technologies that allow large-scale studies of genes and proteins had a remarkable impact on the screening of new and potential vaccine candidates in schistosomiasis. In this postgenomic scenario, bioinformatic technologies have emerged as important tools to mine transcriptomic, genomic, and proteomic databases. These new perspectives are leading to a new round of rational vaccine development. Herein, we discuss different strategies to identify potential S. mansoni vaccine candidates using computational vaccinology.

  18. Association between prostate cancer and schistosomiasis in young patients: a case report and literature review

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    Albert Bacelar

    Full Text Available This case report refers to a 47-year old patient with prostate cancer associated with schistosomiasis mansoni, who was submitted to radical prostatectomy. This is the third report published in the literature with respect to this association, and up to the present time it is still not known whether a cause and effect relationship exists between the two pathologies. The association between schistosomiasis and cancer has been well-documented in bladder cancer; however, there are no data yet proving the association of this disease with prostatic neoplasia. In this report, a third documented case of prostatic adenocarcinoma and schistosomiasis mansoni is described and a literature review is performed.

  19. Transmission of Schistosoma mansoni in Tikur Wuha area, Southern ...

    African Journals Online (AJOL)

    The snails collected were checked for trematode infection by shedding. Laboratory-bred mice were exposed to schistosome cercariae and definite identification of the schistosome was made using eggs and adult worm morphology. Results: The prevalence and intensity of schistosomiasis mansoni was 12% and 69 eggs ...

  20. A rapid diagnostic test for schistosomiasis mansoni

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    Clelia Christina Mello-Silva

    2013-12-01

    Full Text Available This article presents an improvement to the Kato-Katz (KK method, making it faster and more efficient for the visualisation of fertile eggs in stool samples. This modified KK method uses sodium acetate formalin as a fixative and reveals the intensity of infection in less than 1 h, reducing the diagnostic time without increasing the cost. This modified method may contribute to future epidemiological studies in both hospitals and the field due to its rapid and precise diagnostic, which allow for immediate treatment.

  1. The Scourge of Tropical Water Resources, Schistosomiasis,

    Science.gov (United States)

    1980-12-13

    schistosomiasis, we are actually referring to three distinct diseases caused by three different species to helmninth parasites: Schistosoma mansoni, S...African dams in human terms, we need to consider the communities of people and animals that had to be resettled to make way for them: 75,000 people in the...the flies and mosquitoes that spread parasitic infections. Moved into new areas, people and their animals have been exposed to local disease-causing

  2. Schistosomiasis Morbidity and Management of Cases in Africa

    NARCIS (Netherlands)

    M.J. van der Werf (Marieke)

    2003-01-01

    textabstractSchistosomiasis is one of the most prevalent parasitic infections and an important public health problem in many developing countries. The main early symptom if Schistosoma haematobium infection is hematuria, and S. mansoni infection causes bloody diarrhea. Current estimates of the

  3. Reversal of Liver Fibrosis in Chronic Murine Schistosomiasis ...

    African Journals Online (AJOL)

    Purpose: To evaluate the safety, pharmacological effect and mechanism of action of an antifibrotic compound, safironil (SAF)/praziquantel (PZQ) combination on reversal of liver fibrogenesis in chronic murine Schistosomiasis mansoni. Methods: The antifibrotic effect of 0.5, 1 and 2 mg/ml of SAF was evaluated in vitro ...

  4. Current status of intestinal Schistosomiasis and soil- transmitted ...

    African Journals Online (AJOL)

    Bernt Lindtjorn

    Table 2: Prevalence and intensity of intestinal schistosomiasis and ascariasis using Kato-Katz method in 8 elementary schools in Adwa Town, northern Ethiopia, 2007. School. No. Examined. Positive for. Male. Female. Total no. examined. S. mansoni. A. lumbricoides. No. (%) epg. No. (%). Epg. May Guagua. 28. 22. 50.

  5. Whole genome analysis of a schistosomiasis-transmitting freshwater snail

    DEFF Research Database (Denmark)

    Adema, Coen M; Hillier, Ladeana W; Jones, Catherine S

    2017-01-01

    Biomphalaria snails are instrumental in transmission of the human blood fluke Schistosoma mansoni. With the World Health Organization's goal to eliminate schistosomiasis as a global health problem by 2025, there is now renewed emphasis on snail control. Here, we characterize the genome of Biompha...

  6. SmTRC1, a novel Schistosoma mansoni DNA transposon, discloses new families of animal and fungi transposons belonging to the CACTA superfamily

    National Research Council Canada - National Science Library

    DeMarco, Ricardo; Venancio, Thiago M; Verjovski-Almeida, Sergio

    2006-01-01

    ...) and so far have only been described in plants. Large transcriptome and genome sequence data have recently become publicly available for Schistosoma mansoni, a digenetic blood fluke that is a major causative agent of schistosomiasis in humans...

  7. Comparative Study of the Accuracy of Different Techniques for the Laboratory Diagnosis of Schistosomiasis Mansoni in Areas of Low Endemicity in Barra Mansa City, Rio de Janeiro State, Brazil

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    Maria Cristina Carvalho Espírito-Santo

    2015-01-01

    Full Text Available Schistosomiasis constitutes a major public health problem, with an estimated 200 million people infected worldwide. Many areas of Brazil show low endemicity of schistosomiasis, and the current standard parasitological techniques are not sufficiently sensitive to detect the low-level helminth infections common in areas of low endemicity (ALEs. This study compared the Kato-Katz (KK; Hoffman, Pons, and Janer (HH; enzyme-linked immunosorbent assay- (ELISA- IgG and ELISA-IgM; indirect immunofluorescence technique (IFT-IgM; and qPCR techniques for schistosomiasis detection in serum and fecal samples, using the circumoval precipitin test (COPT as reference. An epidemiological survey was conducted in a randomized sample of residents from five neighborhoods of Barra Mansa, RJ, with 610 fecal and 612 serum samples. ELISA-IgM (21.4% showed the highest positivity and HH and KK techniques were the least sensitive (0.8%. All techniques except qPCR-serum showed high accuracy (82–95.5%, differed significantly from COPT in positivity P<0.05, and showed poor agreement with COPT. Medium agreement was seen with ELISA-IgG (Kappa = 0.377 and IFA (Kappa = 0.347. Parasitological techniques showed much lower positivity rates than those by other techniques. We suggest the possibility of using a combination of laboratory tools for the diagnosis of schistosomiasis in ALEs.

  8. Human Schistosomiasis: Clinical Perspective: Review

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    Rashad S. Barsoum

    2013-09-01

    Full Text Available The clinical manifestations of schistosomiasis pass by acute, sub acute and chronic stages that mirror the immune response to infection. The later includes in succession innate, TH1 and TH2 adaptive stages, with an ultimate establishment of concomitant immunity. Some patients may also develop late complications, or suffer the sequelae of co-infection with other parasites, bacteria or viruses. Acute manifestations are species-independent; occur during the early stages of invasion and migration, where infection-naivety and the host’s racial and genetic setting play a major role. Sub acute manifestations occur after maturity of the parasite and settlement in target organs. They are related to the formation of granulomata around eggs or dead worms, primarily in the lower urinary tract with Schistosoma haematobium, and the colon and rectum with Schistosoma mansoni, Schistosoma japonicum, Schistosoma intercalatum and Schistosoma mekongi infection. Secondary manifestations during this stage may occur in the kidneys, liver, lungs or other ectopic sites. Chronic morbidity is attributed to the healing of granulomata by fibrosis and calcification at the sites of oval entrapment, deposition of schistosomal antigen-antibody complexes in the renal glomeruli or the development of secondary amyloidosis. Malignancy may complicate the chronic lesions in the urinary bladder or colon. Co-infection with salmonella or hepatitis viruses B or C may confound the clinical picture of schistosomiasis, while the latter may have a negative impact on the course of other co-infections as malaria, leishmaniasis and HIV. Prevention of schistosomiasis is basically geared around education and periodic mass treatment, an effective vaccine being still experimental. Praziquantel is the drug of choice in the treatment of active infection by any species, with a cure rate of 80%. Other antischistosomal drugs include metrifonate for S. haematobium, oxamniquine for S. mansoni and

  9. Prevalence and clinical correlates of Schistosoma mansoni co-infection among malaria infected patients, Northwest Ethiopia.

    Science.gov (United States)

    Getie, Sisay; Wondimeneh, Yitayih; Getnet, Gebeyaw; Workineh, Meseret; Worku, Ligabaw; Kassu, Afework; Moges, Beyene

    2015-09-28

    In Ethiopia, where malaria and schistosomiasis are co-endemic, co-infections are expected to be high. However, data about the prevalence of malaria-schistosomiasis co-infection and their clinical correlation is lacking. Therefore, the aim of this study was to assess prevalence of Schistosoma mansoni co-infection and associated clinical correlates in malaria patients. A cross-sectional study was conducted in 2013 at Chwahit Health Center, in northwest Ethiopia. Blood film positive malaria patients (N = 205) were recruited for the study. Clinical, parasitological, hematological, and biochemical parameters were assessed from every study participant. Stool samples were also collected and processed with Kato-Katz technique to diagnose and classify intensity of Schistosoma mansoni. The prevalence of Schistosoma mansoni and malaria co-infection was 19.5%. The age group of 16-20 years old was significantly associated with co-infection. Co-infected patients with a moderate-heavy egg burden of Schistosoma mansoni had significantly high mean Plasmodium parasitemia. On the other hand, age group of 6-10 years old and moderate-heavy Schistosoma mansoni co-infection were significantly associated with severe malaria. Prevalence of malaria and Schistosoma mansoni co-infection in the study area was considerably high. Severity of malaria and parasitemia of Plasmodium were associated with certain age groups and intensity of concurrent Schistosoma mansoni. Further study is needed to explore the underlying mechanisms of interaction between malaria and Schistosoma mansoni.

  10. Evaluation of a linear spectral mixture model and vegetation indices (NDVI and EVI in a study of schistosomiasis mansoni and Biomphalaria glabrata distribution in the state of Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Ricardo JPS Guimarães

    2010-07-01

    Full Text Available This paper analyses the associations between Normalized Difference Vegetation Index (NDVI and Enhanced Vegetation Index (EVI on the prevalence of schistosomiasis and the presence of Biomphalaria glabrata in the state of Minas Gerais (MG, Brazil. Additionally, vegetation, soil and shade fraction images were created using a Linear Spectral Mixture Model (LSMM from the blue, red and infrared channels of the Moderate Resolution Imaging Spectroradiometer spaceborne sensor and the relationship between these images and the prevalence of schistosomiasis and the presence of B. glabrata was analysed. First, we found a high correlation between the vegetation fraction image and EVI and second, a high correlation between soil fraction image and NDVI. The results also indicate that there was a positive correlation between prevalence and the vegetation fraction image (July 2002, a negative correlation between prevalence and the soil fraction image (July 2002 and a positive correlation between B. glabrata and the shade fraction image (July 2002. This paper demonstrates that the LSMM variables can be used as a substitute for the standard vegetation indices (EVI and NDVI to determine and delimit risk areas for B. glabrata and schistosomiasis in MG, which can be used to improve the allocation of resources for disease control.

  11. Evaluation of a linear spectral mixture model and vegetation indices (NDVI and EVI) in a study of schistosomiasis mansoni and Biomphalaria glabrata distribution in the state of Minas Gerais, Brazil.

    Science.gov (United States)

    Guimarães, Ricardo J P S; Freitas, Corina C; Dutra, Luciano V; Scholte, Ronaldo G C; Amaral, Ronaldo S; Drummond, Sandra C; Shimabukuro, Yosio E; Oliveira, Guilherme C; Carvalho, Omar S

    2010-07-01

    This paper analyses the associations between Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) on the prevalence of schistosomiasis and the presence of Biomphalaria glabrata in the state of Minas Gerais (MG), Brazil. Additionally, vegetation, soil and shade fraction images were created using a Linear Spectral Mixture Model (LSMM) from the blue, red and infrared channels of the Moderate Resolution Imaging Spectroradiometer spaceborne sensor and the relationship between these images and the prevalence of schistosomiasis and the presence of B. glabrata was analysed. First, we found a high correlation between the vegetation fraction image and EVI and second, a high correlation between soil fraction image and NDVI. The results also indicate that there was a positive correlation between prevalence and the vegetation fraction image (July 2002), a negative correlation between prevalence and the soil fraction image (July 2002) and a positive correlation between B. glabrata and the shade fraction image (July 2002). This paper demonstrates that the LSMM variables can be used as a substitute for the standard vegetation indices (EVI and NDVI) to determine and delimit risk areas for B. glabrata and schistosomiasis in MG, which can be used to improve the allocation of resources for disease control.

  12. Schistosoma mansoni antigen detects Schistosoma mekongi infection.

    Science.gov (United States)

    Nickel, Beatrice; Sayasone, Somphou; Vonghachack, Youthanavanh; Odermatt, Peter; Marti, Hanspeter

    2015-01-01

    Northern Cambodia and Southern Laos are highly endemic for Schistosoma mekongi. However, there is currently no immunological assay available that is specific for this form of schistosomiasis. We have validated Schistosoma mansoni antigens to detect S. mekongi-directed antibodies in human sera collected from a highly S. mekongi endemic region in Laos. On two consecutive days stool samples of 234 individuals were analyzed by Kato-Katz for presence of S. mekongi eggs and the results were correlated with serology. A sensitivity of 94.5% was calculated for a combination of ELISA and indirect fluorescence assay (IFA) as compared to the detection of S. mekongi eggs in stool samples as gold standard. The results demonstrate that S. mansoni antigens can be used for the diagnosis of S. mekongi infections. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Effect of maternal Schistosoma mansoni infection and praziquantel treatment during pregnancy on Schistosoma mansoni infection and immune responsiveness among offspring at age five years.

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    Robert Tweyongyere

    Full Text Available Offspring of Schistosoma mansoni-infected women in schistosomiasis-endemic areas may be sensitised in-utero. This may influence their immune responsiveness to schistosome infection and schistosomiasis-associated morbidity. Effects of praziquantel treatment of S. mansoni during pregnancy on risk of S. mansoni infection among offspring, and on their immune responsiveness when they become exposed to S. mansoni, are unknown. Here we examined effects of praziquantel treatment of S. mansoni during pregnancy on prevalence of S. mansoni and immune responsiveness among offspring at age five years.In a trial in Uganda (ISRCTN32849447, http://www.controlled-trials.com/ISRCTN32849447/elliott, offspring of women treated with praziquantel or placebo during pregnancy were examined for S. mansoni infection and for cytokine and antibody responses to SWA and SEA, as well as for T cell expression of FoxP3, at age five years.Of the 1343 children examined, 32 (2.4% had S. mansoni infection at age five years based on a single stool sample. Infection prevalence did not differ between children of treated or untreated mothers. Cytokine (IFNγ, IL-5, IL-10 and IL-13 and antibody (IgG1, Ig4 and IgE responses to SWA and SEA, and FoxP3 expression, were higher among infected than uninfected children. Praziquantel treatment of S. mansoni during pregnancy had no effect on immune responses, with the exception of IL-10 responses to SWA, which was higher in offspring of women that received praziquantel during pregnancy than those who did not.We found no evidence that maternal S. mansoni infection and its treatment during pregnancy influence prevalence and intensity of S. mansoni infection or effector immune response to S. mansoni infection among offspring at age five years, but the observed effects on IL-10 responses to SWA suggest that maternal S. mansoni and its treatment during pregnancy may affect immunoregulatory responsiveness in childhood schistosomiasis. This might have

  14. Vaccine strategies against schistosomiasis

    Directory of Open Access Journals (Sweden)

    A. Capron

    1992-01-01

    Full Text Available In this review the authors analyze the effector and regulatory mechanisms in the immune response to schistosomiasis. To study these mechanisms two animal models were used, mouse and rat. The mouse totaly permissive host like human, show prominent-T cell control in the acquisition of resistance. But other mechanisms like antibody mediated cytotoxity (ADCC involving eosinophils and IgG antibodies described in humans, are observed in rats. Also in this animal, it is observed specific IgE antibody high production and blood and tisssue eosinophilia. Using the rat model and schistosomula as target, some ADCC features have emerged: the cellular population involved are bone marrow derived inflammatory cell (mononuclear phagocytes, eosinophils and platelets, interacting with IgE through IgE Fc receptors. Immunization has been attempted using the recombinant protein Sm28/GST. Protection has been observed in rodents with significant decrease of parasite fecundity and egg viability affecting the number, size and volume of liver egg granulomas. The association of praziquantel and immunization with with Sm28/GST increases the resistance to infection and decreases egg viability. The authors suggest the possibility of the stablishment of a future vaccine against Schistosoma mansoni.

  15. Further development of the baboon as a model for acute schistosomiasis

    Directory of Open Access Journals (Sweden)

    Raymond T. Damian

    1992-01-01

    Full Text Available Baboons develop a syndrome, including eosinophilia and transient fever, after infection with carcariae of Schistosoma mansoni that is consistent with the human syndrome of acute schistosomiasis. Radiotelemetry can be used to follow the course of fever in infected baboons. Individual variations in intensity of disease were noted in baboons. These symptoms and signs were more closely linked to the onset of oviposition by the newly matured worms than they were to the presence of migrating schistosoma or maturing worms. The baboon is concluded to be a suitable and useful model for human acute schistosomiasis mansoni.

  16. Biosensor for Hepatocellular Injury Corresponds to Experimental Scoring of Hepatosplenic Schistosomiasis in Mice

    Directory of Open Access Journals (Sweden)

    Martina Sombetzki

    2016-01-01

    Full Text Available Severe hepatosplenic injury of mansonian schistosomiasis is caused by Th2 mediated granulomatous response against parasite eggs entrapped within the periportal tissue. Subsequent fibrotic scarring and deformation/sclerosing of intrahepatic portal veins lead to portal hypertension, ascites, and oesophageal varices. The murine model of Schistosoma mansoni (S. mansoni infection is suitable to establish the severe hepatosplenic injury of disease within a reasonable time scale for the development of novel antifibrotic or anti-infective strategies against S. mansoni infection. The drawback of the murine model is that the material prepared for complex analysis of egg burden, granuloma size, hepatic inflammation, and fibrosis is limited due to small amounts of liver tissue and blood samples. The objective of our study was the implementation of a macroscopic scoring system for mice livers to determine infection-related organ alterations of S. mansoni infection. In addition, an in vitro biosensor system based on the detection of hepatocellular injury in HepG2/C3A cells following incubation with serum of moderately (50 S. mansoni cercariae and heavily (100 S. mansoni cercariae infected mice affirmed the value of our scoring system. Therefore, our score represents a valuable tool in experimental schistosomiasis to assess severity of hepatosplenic schistosomiasis and reduce animal numbers by saving precious tissue samples.

  17. GPCR and IR genes in Schistosoma mansoni miracidia

    OpenAIRE

    Liang, Di; Zhao, Min; Wang, Tianfang; McManus, Donald P.; Cummins, Scott F.

    2016-01-01

    Background Schistosoma species are responsible for the disease schistosomiasis, a highly prevalent helminthic disease that requires a freshwater snail as intermediate host. The S. mansoni free-living miracidium must utilize olfaction to find a suitable snail host, and certain types of rhodopsin G protein-coupled receptors (GPCRs) and ionotropic receptors (IRs) have been identified as olfactory receptors in other animal phyla. The Schistosoma genome project, together with the recent availabili...

  18. Enhancing Schistosomiasis Control Strategy for Zimbabwe: Building on Past Experiences

    Directory of Open Access Journals (Sweden)

    Moses J. Chimbari

    2012-01-01

    Full Text Available Schistosoma haematobium and Schistosoma mansoni are prevalent in Zimbabwe to levels that make schistosomiasis a public health problem. Following three national surveys to map the disease prevalence, a national policy on control of schistosomiasis and soil transmitted helminths is being developed. This paper reviews the experiences that Zimbabwe has in the area of schistosomiasis control with a view to influence policy. A case study approach to highlight key experiences and outcomes was adopted. The benefits derived from intersectoral collaboration that led to the development of a model irrigation scheme that incorporates schistosomiasis control measures are highlighted. Similarly, the benefits of using plant molluscicides and fish and duck biological agents (Sargochromis codringtonii and Cairina moschata are highlighted. Emphasis was also placed on the importance of utilizing locally developed water and sanitation technologies and the critical human resource base in the area of schistosomiasis developed over years. After synthesis of the case studies presented, it was concluded that while there is a need to follow the WHO recommended guidelines for schistosomiasis control it is important to develop a control strategy that is informed by work already done in the country. The importance of having a policy and local guidelines for schistosomiasis control is emphasized.

  19. HIV and schistosomiasis in rural Zimbabwe

    DEFF Research Database (Denmark)

    Kotzé, Sebastian Ranzi; Zinyama-Gutsire, Rutendo; Kallestrup, Per

    2015-01-01

    BACKGROUND: Vitamin A has widespread effects on immune function and is therefore interesting in HIV-infection. Retinol-binding protein (RBP or RBP4) is a negative acute-phase protein and a marker of vitamin A status. Our aim was to investigate the association of RBP with HIV progression, infection...... with schistosomiasis, inflammatory cytokines, and mortality. METHODS: The study included 192 HIV-infected and 177 HIV-uninfected individuals from Mupfure in rural Zimbabwe. Of these, 208 were infected with Schistosoma haematobium, 27 with S. mansoni and 48 with both. Plasma RBP, HIV-RNA, CD4 cell count, haemoglobin......, cytokines, clinical staging (CDC category), self-reported level of function (Karnoffsky Performance Score, KPS) and schistosomiasis status were assessed at baseline. Participants were followed up for survival 3-4 years post-enrolment. RESULTS: RBP levels were lower in HIV-infected individuals(p

  20. Uma concepção popular sobre a esquistossomose mansônica: os modos de transmissão e prevenção na perspectiva de gênero A popular concept of schistosomiasis mansoni: modes of transmission and prevention in the perspective of gender differences

    Directory of Open Access Journals (Sweden)

    Ceci V. Noronha

    1995-03-01

    Full Text Available Estudo sobre as concepções e práticas populares acerca da transmissão e prevenção das parasitoses, com ênfase para a esquistossomose mansônica. Explora a existência de um sistema popular de cuidados de saúde que mescla elementos da biomedicina e da medicina tradicional como forma de compreender e manejar os fenômenos de saúde/doença. Descreve as diferenças entre morbidade e sexo/gênero na concepção dos sujeitos entrevistados. Apresenta o discurso popular sobre as parasitoses, discutindo as dificuldades das ações de controle. Considera as contradições entre hábitos e valores culturais e as medidas de controle conhecidas, criticando a imprecisão das ações educativas nos programas oficiais de intervenção.This is a study on popular ideas, beliefs and practices concerning the transmission and prevention of parasitic diseases, specifically schistosomiasis mansoni. The author explored the existence of a popular belief system within the health care system, combining elements from biomedicine and folk medicine for the understanding and management of the health/disease phenomenon. The study describes the differences in perception of morbidity and gender among the interviewwees. Finally, the study presents popular discourse on parasitic diseases and discusses diffculties with control measures. It considers the contradiction between cultural values and habits and conventional control measures, critically assessing the lack of precision in health education measures under government prevention programs.

  1. The feasibility of MS and advanced data processing for monitoring Schistosoma mansoni infection

    DEFF Research Database (Denmark)

    Balog, Crina I.A.; Alexandrov, Theodore; Derks, Rico J.

    2010-01-01

    Sensitive diagnosis, monitoring of disease progression and the evaluation of chemotherapeutic interventions are of prime importance for the improvement of control and prevention strategies for Schistosomiasis. The aim of the present study was to identify novel markers of Schistosoma mansoni infec...

  2. Knowledge, attitude, and practices towards schistosomiasis among rural population in Yemen.

    Science.gov (United States)

    Sady, Hany; Al-Mekhlafi, Hesham M; Atroosh, Wahib M; Al-Delaimy, Ahmed K; Nasr, Nabil A; Dawaki, Salwa; Al-Areeqi, Mona A; Ithoi, Init; Abdulsalam, Awatif M; Chua, Kek Heng; Surin, Johari

    2015-08-25

    Schistosomiasis is highly prevalent in Yemen, with an estimated 3 million cases, particularly among rural communities. This community-based study aims to evaluate the knowledge, attitude and practices (KAP) on schistosomiasis among rural communities in Yemen. A cross-sectional study was carried out among 250 households from ten rural districts in Yemen. Overall, 400 children were screened for urogenital and intestinal schistosomiasis. Moreover, parents were interviewed using a pre-tested questionnaire to collect information about the demographic and socioeconomic information and their KAP concerning schistosomiasis. A total of 127 (31.8%) children were found to be excreting schistosome eggs in either their urine or faeces (22.5% S. haematobium and 8.0% S. mansoni). Although 92.4% of the respondents had heard about schistosomiasis, 49.8%, 68.0% and 47.2% had knowledge concerning the transmission, signs and symptoms, and prevention, respectively. In addition, 77.1% considered schistosomiasis as harmful while 48.5% believed that schistosomiasis could be prevented, albeit their practices to prevent infections were still inadequate. Significant associations between the KAP and age, education, employment status and household monthly income were reported (P Yemen was inadequate, and that this could be a challenging obstacle to the elimination of schistosomiasis in these communities. Besides the current mass drug administration, school and community-based health education regarding schistosomiasis is imperative among these communities to significantly reduce the transmission and morbidity of schistosomiasis.

  3. Ocular pathological changes in hamsters experimentally infected with Schistosoma mansoni.

    Science.gov (United States)

    Ismail, H I H; Ashour, D S; Abou Rayia, D M; Ali, A L

    2016-11-01

    Ocular lesions have been reported in patients with schistosomiasis; however, the problem with studying schistosomal infection of the human eye is that biopsies are almost impossible to take, and histopathological examination of suspicious lesions can only be undertaken post-mortem or after enucleation. This work aimed to study the possible effects and pathogenesis of schistosomiasis on the eye. This study involved 55 hamsters; five hamsters remained non-infected and the remaining 50 hamsters were infected with Schistosoma mansoni cercariae. Infected hamsters were sacrificed on weeks 8, 12, 16 and 20 post-infection (pi). Eye sections were prepared and stained for histopathological and immunohistochemical studies. Histopathological changes detected in hamsters infected after 16 and 20 weeks included looseness and oedema of the innermost retinal layers together with hyperplastic polypoid growth. Neither eggs nor granulomata were detected in eye sections throughout the experimental period. Deposition of S. mansoni antigen was revealed in 35% of infected hamsters. Later, on weeks 16 and 20 pi, moderate subepithelial conjuctival deposits and marked subchoroidal and scleral deposition were detected. In conclusion, the deposition of schistosomal antigen and immune complexes may play a pivotal role in the ocular changes that occur in schistosomiasis, even in the absence of detectable Schistosoma eggs. Schistosomiasis should be suspected in cases with unexplained ophthalmological findings, especially in endemic areas.

  4. Aspectos ultrassonográficos associados à morbidade de formas clínicas crônicas de esquistossomose mansônica, utilizando-se protocolo proposto pela Organização Mundial da Saúde Sonographic features associated with morbidity of chronic clinical presentations of schistosomiasis mansoni using the protocol proposed by the World Health Organization

    Directory of Open Access Journals (Sweden)

    Daniel Alvarenga Fernandes

    2013-02-01

    Full Text Available OBJETIVO: Avaliar aspectos ultrassonográficos associados à morbidade em pacientes com formas clínicas crônicas de esquistossomose mansônica, utilizando-se protocolo proposto pela Organização Mundial da Saúde (OMS. MATERIAIS E MÉTODOS: Foram avaliadas duas populações distintas: a área endêmica e b institucional terciária, com histopatológico confirmando fibrose. Critérios de inclusão: diagnóstico confirmado por parasitológico de fezes para Schistosoma mansoni (método Kato-Katz. Critérios de exclusão: sorologia positiva para HIV, HTLV-1, VHB ou VHC. Foi utilizado protocolo ultrassonográfico de Niamey, proposto pela OMS. RESULTADOS: Avaliando-se isoladamente as medidas dos espaços periportais, estas se mostraram sem alterações em 21% dos indivíduos com doença avançada da instituição terciária. Utilizando-se todos os parâmetros do protocolo, 100% dos indivíduos da instituição terciária, com forma grave da doença, apresentaram fibrose periportal avançada. Em pacientes hepatoesplênicos da área endêmica não se identificou fibrose à ultrassonografia. CONCLUSÃO: O protocolo ultrassonográfico proposto pela OMS detecta fibrose periportal avançada nos pacientes com forma grave da doença, com maior sensibilidade do que a medida do espaço periportal isoladamente. A complexidade de identificação das fases iniciais da fibrose periportal, em áreas endêmicas, pela ultrassonografia, pode suscitar o campo da complementação diagnóstica e a continuidade do aprimoramento dos protocolos ultrassonográficos nestas áreas.OBJECTIVE: To evaluate sonographic features associated with morbidity in patients with chronic clinical presentations of schistosomiasis mansoni, according to the protocol proposed by the World Health Organization (WHO. MATERIALS AND METHODS: Two distinctive populations were evaluated: a patients from an endemic area, and b patients from a tertiary institution, with histopathologically confirmed

  5. Photodynamic therapy for Schistosoma mansoni: Promising outcomes.

    Science.gov (United States)

    de Melo, Nathália Bandeira; Dos Santos, Letícia Fernanda Moreira; de Castro, Mayara Santos; Souza, Raquel Lopes Martins; Marques, Marcos José; Castro, Aline Pereira; de Castro, Andreísa Teixeira; de Carli, Marina Lara; Hanemann, João Adolfo Costa; Silva, Matheus Siqueira; Moraes, Gabriel de Oliveira Isac; Beijo, Luiz Alberto; Brigagão, Maísa Ribeiro Pereira Lima; Sperandio, Felipe Fornias

    2017-11-01

    The purpose of this study was to assess, for the very first time, the effects of photodynamic therapy (PDT) on Schistosoma mansoni in vitro by measuring reactive oxygen species (ROS) generation throughout the treatment, as well as the behavior of the parasites (mating, motility and contraction/shortening), and damage to their tegument and excretory systems. The parasites were divided into 4 groups: control, photosensitizer, laser and PDT. Light irradiation was delivered with an InGaAlP low-level laser device operating at 660nm, with 40mW and 100J/cm(2). For PDT, different toluidine blue dye (TBO) concentrations and times of exposure were utilized. Interestingly, TBO-mediated PDT was able to kill S. mansoni (P<0.001) due to the significant amount of ROS released that inflicted damages in the tegument and excretory system, as well as contraction and cessation of motility. In addition, males of S. mansoni were shown to be more sensitive to PDT if compared to their corresponding females when the optimal TBO concentration of 31.2μL was considered (P=0.0126). PDT presents two major advantages: not inducing microbial resistance and also lacking adverse effects. Therefore, PDT may become a promising therapeutic alternative for schistosomiasis in the near future, especially for cases of allergy and resistance to praziquantel. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. New insights into the genetic diversity of Schistosoma mansoni and S. haematobiumin Yemen.

    Science.gov (United States)

    Sady, Hany; Al-Mekhlafi, Hesham M; Webster, Bonnie L; Ngui, Romano; Atroosh, Wahib M; Al-Delaimy, Ahmed K; Nasr, Nabil A; Chua, Kek Heng; Lim, Yvonne A L; Surin, Johari

    2015-10-20

    Human schistosomiasis is a neglected tropical disease of great importance that remains highly prevalent in Yemen, especially amongst rural communities. In order to investigate the genetic diversity of human Schistosoma species, a DNA barcoding study was conducted on S. mansoni and S. haematobium in Yemen. A cross-sectional study was conducted to collect urine and faecal samples from 400 children from five provinces in Yemen. The samples were examined for the presence of Schistosoma eggs. A partial fragment of the schistosome cox1 mitochondrial gene was analysed from each individual sample to evaluate the genetic diversity of the S. mansoni and S. haematobium infections. The data was also analysed together with previous published cox1 data for S. mansoni and S. haematobium from Africa and the Indian Ocean Islands. Overall, 31.8 % of participants were found to be excreting schistosome eggs in either the urine or faeces (8.0 % S. mansoni and 22.5 % S. haematobium). Nineteen unique haplotypes of S. mansoni were detected and split into four lineages. Furthermore, nine unique haplotypes of S. haematobium were identified that could be split into two distinct groups. This study provides novel and interesting insights into the population diversity and structure of S. mansoni and S. haematobium in Yemen. The data adds to our understanding of the evolutionary history and phylogeography of these devastating parasites whilst the genetic information could support the control and monitoring of urogenital and intestinal schistosomiasis in these endemic areas.

  7. Epidemic transmission of intestinal schistosomiasis in the seasonal part of the Okavango Delta, Botswana

    DEFF Research Database (Denmark)

    Appleton, C.C.; Ellery, W.N.; Byskov, Jens

    2008-01-01

    A well documented epidemic of human intestinal schistosomiasis caused by Schistosoma mansoni occurred at Maun in the seasonal part of the Okavango Delta, Botswana, building from very few cases in the 1950s and early 1960s to a peak prevalence of >80% in the 1980s. A retrospective analysis...

  8. Endomyocardial fibrosis (EMF) in a Ugandan child with advanced hepatosplenic schistosomiasis: coincidence or connection?

    Science.gov (United States)

    Bustinduy, Amaya L; Luzinda, Kenneth; Mpoya, Simon; Gothard, Philip; Stone, Neil; Wright, Stephen; Stothard, J Russell

    2014-10-01

    An association between late-stage hepatosplenic schistosomiasis and endomyocardial fibrosis (EMF) has been suggested but not proven. We present the case of a 12-year-old Ugandan boy with striking comorbidities, including advanced periportal fibrosis caused by Schistosoma mansoni infection and right ventricular EMF, and discuss the possible correlation between both diseases. © The American Society of Tropical Medicine and Hygiene.

  9. Schistosomiasis and infection with human immunodeficiency virus 1 in rural Zimbabwe

    DEFF Research Database (Denmark)

    Erikstrup, Christian; Kallestrup, Per; Zinyama-Gutsire, Rutendo B L

    2008-01-01

    We previously reported that treatment for schistosomiasis in persons infected with human immunodeficiency virus 1 (HIV-1) attenuated HIV replication as measured by plasma HIV RNA. We investigated systemic inflammation as measured by plasma levels of soluble tumor necrosis factor-alpha receptor II...... (sTNF-rII), interleukin-8, (IL-8), and IL-10 during schistosomiasis and HIV co-infection and after schistosomiasis treatment. The cohort was composed of 378 persons who were or were not infected with HIV-1, Schistosoma haematobium, or S. mansoni. Schistosomiasis-infected persons were randomized...... to receive praziquantel (40 mg/kg) at baseline or at the three-month follow-up. sTNF-rII and IL-8 were positively associated with schistosomiasis intensity as measured by circulating anodic antigen (CAA), regardless of HIV status. Interleukin-10 was positively associated with CAA in HIV-negative participants...

  10. GPCR and IR genes in Schistosoma mansoni miracidia.

    Science.gov (United States)

    Liang, Di; Zhao, Min; Wang, Tianfang; McManus, Donald P; Cummins, Scott F

    2016-10-26

    Schistosoma species are responsible for the disease schistosomiasis, a highly prevalent helminthic disease that requires a freshwater snail as intermediate host. The S. mansoni free-living miracidium must utilize olfaction to find a suitable snail host, and certain types of rhodopsin G protein-coupled receptors (GPCRs) and ionotropic receptors (IRs) have been identified as olfactory receptors in other animal phyla. The Schistosoma genome project, together with the recent availability of proteomic databases, allowed for studies to explore receptors within S. mansoni, some of which may contribute to host finding. We have identified 17 rhodopsin-type GPCR sequences in S. mansoni belonging to four subclasses, including ligand-specific GPCRs (i.e. neuropeptide and opsin). RT-PCR demonstrated the expression of nine out of the 17 GPCRs in the free-living miracidia, each of which have been characterized for homology to S. haematobium. Among the nine GPCRs, two are predicted as Gq-opsins. We also describe the characterization of a Schistosoma-encoded IR based on similarity with other species IR and conservation of IR-like domains. Schistosoma mansoni IR is expressed in miracidia at 3 and 6 h post-hatch. The identification of receptors in S. mansoni miracidia, presented here, contributes not only to further understanding of Schistosoma biology and signal transduction but also provides a basis for approaches that may modify parasite behaviour.

  11. Praziquantel treatment decreases Schistosoma mansoni genetic diversity in experimental infections.

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    Regina Coeli

    Full Text Available BACKGROUND: Schistosomiasis has a considerable impact on public health in many tropical and subtropical areas. In the new world, schistosomiasis is caused by the digenetic trematode Schistosoma mansoni. Chemotherapy is the main measure for controlling schistosomiasis, and the current drug of choice for treatment is praziquantel (PZQ. Although PZQ is efficient and safe, its repetitive large-scale use in endemic areas may lead to the selection of resistant strains. Isolates less susceptible to PZQ have been found in the field and selected for in the laboratory. The impact of selecting strains with a decreased susceptibility phenotype on disease dynamics and parasite population genetics is not fully understood. This study addresses the impact of PZQ pressure on the genetics of a laboratory population by analyzing frequency variations of polymorphic genetic markers. METHODOLOGY: Infected mice were treated with increasing PZQ doses until the highest dose of 3 × 300 mg/Kg was reached. The effect of PZQ treatment on the parasite population was assessed using five polymorphic microsatellite markers. Parasitological and genetic data were compared with those of the untreated control. After six parasite generations submitted to treatment, it was possible to obtain a S. mansoni population with decreased susceptibility to PZQ. In our experiments we also observed that female worms were more susceptible to PZQ than male worms. CONCLUSIONS: The selective pressure exerted by PZQ led to decreased genetic variability in S. mansoni and increased endogamy. The understanding of how S. mansoni populations respond to successive drug pressure has important implications on the appearance and maintenance of a PZQ resistance phenotype in endemic regions.

  12. The hidden epidemic of schistosomiasis in recent African immigrants and asylum seekers to Italy.

    Science.gov (United States)

    Beltrame, Anna; Buonfrate, Dora; Gobbi, Federico; Angheben, Andrea; Marchese, Valentina; Monteiro, Geraldo Badona; Bisoffi, Zeno

    2017-08-01

    The prevalence of schistosomiasis among recent refugees from sub-Saharan Africa in Italy is unknown. This is a retrospective review of African immigrants screened at Centre for Tropical Diseases of Negrar from March 2014 to February 2016. Of the 373 immigrants tested, 34% were positive at least at one schistosomiasis test. The proportion of positive ELISA serology was 103/373 (27.6%). At microscopy, infected subjects were 65/373 (17.4%), (51% Schistosoma haematobium, 38% Schistosoma mansoni, 11% both). CCA antigen for S. mansoni was positive in 47/373 individuals (12.6%). We found a particularly high positivity rate in subjects from Mali (72.1%) and Ivory Coast (48%). This "hidden epidemic" of schistosomiasis cannot be longer neglected, considering the risk of severe complications, and the effective and inexpensive treatment available.

  13. Drug resistance in Schistosomiasis: a review

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    John I. Bruce

    1987-01-01

    Full Text Available Drug resistance associated with the treatment of human schistosomiasis appears to be an emerging problem requiring more attention from the scientific community than the subject currently receives. Drug-resistant strains of Schistosoma mansoni have been isolated by various investigators as a result of laboratory experimentation or from a combination of field and laboratory studies. Review of this data appears to indicate that the lack of susceptibility observed for some of the isolated strains cannot be ascribed solely to previous administration of antischistosome drugs and thus further studies are required to elucidate this phenomena. Strains of S. mansoni have now been identified from Brazil which are resistant to oxamniquine, hycanthone and niridazole; from Puerto Rico which are resistant to hycanthone and oxamniquine; and from Kenya which are resistant to niridazole and probably oxamniquine. Strains derived by in vitro selection and resistant to oxamniquine and possibly to oltipraz are also available. All of these strains are currently maintained in the laboratory in snails and mice, thus providing for the first time an opportunity for indepth comparative studies. Preliminary data indicates that S. haematobium strains resistant to metrifonate may be occurring in Kenya. This problem could poise great difficulty in the eventual development of antischistosomal agents. Biomphalaria glabrata from Puerto Rico and Brazil were found to be susceptible to drug-resistant S. mansoni from each country.

  14. Studies on heterologous immunity in schistosomiasis*

    Science.gov (United States)

    Amin, M. A.; Nelson, G. S.; Saoud, M. F. A.

    1968-01-01

    Previous studies on heterologous immunity in mice have indicated that Schistosoma bovis and S. mattheei could be used to limit the severity of infection resulting from subsequent challenge by S. mansoni. These observations have now been extended to study the immunizing effect in rhesus monkeys of both S. mattheei and S. bovis. The bovine schistosomes were shown to be relatively non-pathogenic in rhesus monkeys. Immunization with 1000-2000 cercariae resulted in a marked reduction in the pathogenic effect of subsequent challenge with S. mansoni. This effect was demonstrated by a decrease in the worm load and tissue egg densities in 10 immunized monkeys as compared with 5 control animals. There was no correlation between fluorescent antibody titres and the intensity of infection or the degree of acquired immunity. There was a cross-reaction between S. mansoni and the bovine schistosomes. It is suggested that natural heterologous immunity (zooprophylaxis) may be of considerable epidemiological importance in determining the severity of schistosomiasis in man. PMID:4970323

  15. Schistosomiasis and associated infections

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    Lambertucci JR

    1998-01-01

    Full Text Available In hospital-based series viral hepatitis B has been frequently described in association with schistosomiasis whilst in field-based studies the association has not been confirmed. The association between schistosomiasis and Salmonella bacteraemia has been well documented. More recently, acute schistosomiasis has been shown to be a facilitating factor in the genesis of pyogenic liver abscesses caused by Staphylococcus aureus. New evidences indicate an interaction between the acquired immunodeficiency syndrome (AIDS and schistosomiasis. In this paper, data on the association of schistosomiasis with other infections are updated.

  16. Experimental schistosomiasis in the Common Marmoset Callithrix jacchus

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    Oliveira Ana Luna de

    2004-01-01

    Full Text Available In order to evaluate Callithrix jacchus as an animal model for mansoni schistosomiasis, a group of 10 male animals were once percutaneously exposed to 250 cercariae of the Schistosoma mansoni SLM (São Lourenço da Mata strain. Animals were periodically bled for measuring serum level of enzymes and proteins and for blood cell counting. When comparing pre-infection to post-infection values, a significant increase was found for alkaline phosphatase at 15 to 120 days p.i., differential counts of eosinophil at 45 and 60 days, and total protein and global eosinophil counts at 120 days. No Schistosoma mansoni eggs were found in stools. Adult worms of small size were recovered from five animals. At day 120, the number of Schistosoma mansoni eggs/g of tissue was 0-289.7 (liver, 0-30.1 (large intestine and 0-171.4 (small intestine. These findings lead us to classify Callithrix jacchus as a non-permissive host to the SLM strain of Schistosoma mansoni.

  17. Fast evolutionary rates associated with functional loss in class I glucose transporters of Schistosoma mansoni.

    Science.gov (United States)

    Cabezas-Cruz, Alejandro; Valdés, James J; Lancelot, Julien; Pierce, Raymond J

    2015-11-19

    . Finally, taking into account the differences in the dynamics of glucose transport of the Platyhelminthes-specific transporters of S. mansoni compared to that of humans, we conclude that S. mansoni glucose transporters may be targets for rationally designed drugs against schistosomiasis.

  18. Histopathological study of Schistosoma mansoni infection in the murine model using the PC (Pará) and LILA (Maranhão) strains

    OpenAIRE

    Lopes, Igor da Costa; Santos, Vanessa RC dos; Souza, Vera LR Barros; Rodrigues, Izabel R de C

    2006-01-01

    Experimental models of Schistosoma mansoni infections in mammals have contributed greatly in understanding the pathology and pathogenesis of human infection. The absence of earlier reviews regarding specific strains of the Amazon region prompted research, which the main objective was to describe histopathological lesions in different phases of schistosomiasis in a murine model using PC (Pará) and LILA (Maranhão) S. mansoni strains. One hundred and eighty young female albino swiss mice (Mus mu...

  19. Functional Diversity of the Schistosoma mansoni Tyrosine Kinases

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    Lívia G. A. Avelar

    2011-01-01

    Full Text Available Schistosoma mansoni, one of the causative agents of schistosomiasis, has a complex life cycle infecting over 200 million people worldwide. Such a successful and prolific parasite life cycle has been shown to be dependent on the adaptive interaction between the parasite and hosts. Tyrosine kinases (TKs play a key role in signaling pathways as demonstrated by a large body of experimental work in eukaryotes. Furthermore, comparative genomics have allowed the identification of TK homologs and provided insights into the functional role of TKs in several biological systems. Finally, TK structural biology has provided a rational basis for obtaining selective inhibitors directed to the treatment of human diseases. This paper covers the important aspects of the phospho-tyrosine signaling network in S. mansoni, Caenorhabditis elegans, and humans, the main process of functional diversification of TKs, that is, protein-domain shuffling, and also discusses TKs as targets for the development of new anti-schistosome drugs.

  20. The spatial distribution of Schistosoma mansoni infection in four regions of western Côte d’Ivoire

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    Rufin K. Assaré

    2015-06-01

    Full Text Available Schistosomiasis poses a considerable public health burden in sub- Saharan Africa and a sound understanding of the spatial distribution facilitates to better target control interventions. The objectives of this study were i to assess the prevalence of Schistosoma mansoni among school-aged children in four regions of western Côte d’Ivoire; ii to determine demographic, climatic and environmental factors that influence the distribution of S. mansoni; and iii to map and predict the distribution of S. mansoni in non-sampled locations. Parasitological surveys were carried out in 264 schools from June to December 2011. In each school, we aimed to examine 50 children for S. mansoni infection using duplicate Kato-Katz thick smears. Schools were georeferenced using a hand-held global positioning system receiver. Demographic data were obtained from readily available school lists, while climatic and environmental data were extracted from open-access remote sensing databases. Multivariable, binary non-spatial models and a Bayesian geostatistical logistic regression model were used to identify demographic, climatic and environmental risk factors for S. mansoni infection. Risk maps were developed based on observed S. mansoni prevalences and using Bayesian geostatistical models to predict prevalences at non-sampled locations. Overall, 12,462 children provided a sufficiently large stool sample to perform at least one Kato-Katz thick smear. The observed overall prevalence of S. mansoni infection was 39.9%, ranging from 0 to 100% at the unit of the school. Bayesian geostatistical analysis revealed that age, sex, altitude and difference between land surface temperature at day and night were significantly associated with S. mansoni infection. The S. mansoni risk map presented here is being been used by the national schistosomiasis control programme for spatial targeting of praziquantel and other interventions.

  1. Use of Indicator Kriging to Investigate Schistosomiasis in Minas Gerais State, Brazil

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    Ricardo J. P. S. Guimarães

    2012-01-01

    Full Text Available Geographic Information Systems (GISs are composed of useful tools to map and to model the spatial distribution of events that have geographic importance as schistosomiasis. This paper is a review of the use the indicator kriging, implemented on the Georeferenced Information Processing System (SPRING to make inferences about the prevalence of schistosomiasis and the presence of the species of Biomphalaria, intermediate hosts of Schistosoma mansoni, in areas without this information, in the Minas Gerais State, Brazil. The results were two maps. The first one was a map of Biomphalaria species, and the second was a new map of estimated prevalence of schistosomiasis. The obtained results showed that the indicator kriging can be used to better allocate resources for study and control of schistosomiasis in areas with transmission or the possibility of disease transmission.

  2. Risk factors for human schistosomiasis in the Upper Benue valley, in northern Cameroon.

    Science.gov (United States)

    Ndassa, A; Mimpfoundi, R; Gake, B; Paul Martin, M V; Poste, B

    2007-09-01

    The Upper Benue valley is inhabited by human populations of mixed background and socio-economic status. The area is an old and intense focus of both urinary schistosomiasis (caused by Schistosoma haematobium) and intestinal schistosomiasis (caused by S. mansoni). Most of the local villages have stand-pipes that provide clean drinking water but bathing, laundry, dishwashing and swimming are largely confined to nearby, snail-infested rivers, streams, irrigation canals and pools. The results of interviews and a multivariate analysis indicated that, in this region of Cameroon, a subject's age, knowledge of schistosomiasis, ethnic group and intensity of water contact (with rivers, streams and pools) were all significantly associated with schistosome infection. Curiously, a high level of knowledge about schistosomiasis was positively associated with infection.

  3. [Identification of schistosomiasis risk areas using spatial analysis in Lauro de Freitas, Bahia State, Brazil].

    Science.gov (United States)

    Cardim, Luciana Lobato; Ferraudo, Antonio Sergio; Pacheco, Selma Turrioni Azevedo; Reis, Renato Barbosa; Silva, Marta Mariana Nascimento; Carneiro, Deborah Daniela M Trabuco; Bavia, Maria Emilia

    2011-05-01

    The spread of schistosomiasis mansoni defies efforts by Brazil's Unified National Health System, thus demonstrating the need to reassess endemic control programs in the country. The aim of this study was to demarcate geographic areas at risk of schistosomiasis in Lauro de Freitas, Bahia State, Brazil, and to establish the epidemiological and socioeconomic profile of the disease in this municipality (county). Kernel density estimator exploratory analysis was used for visual identification of areas at risk. Kulldorff & Nagarwalla's spatial analysis was used to obtain statistically significant clusters and to measure risk. These technologies identified four risk areas for schistosomiasis. Clusters identified within the risk areas were characterized by lower socioeconomic conditions. Multiple correspondence analyses showed a distinct profile for positive patients in the primary cluster. The techniques employed here represent an important methodological acquisition for tracking and controlling schistosomiasis in Lauro de Freitas.

  4. Assessment of toxicity of Moringa oleifera flower extract to Biomphalaria glabrata, Schistosoma mansoni and Artemia salina.

    Science.gov (United States)

    Rocha-Filho, Cláudio A A; Albuquerque, Lidiane P; Silva, Luanna R S; Silva, Patrícia C B; Coelho, Luana C B B; Navarro, Daniela M A F; Albuquerque, Monica C P A; Melo, Ana Maria M A; Napoleão, Thiago H; Pontual, Emmanuel V; Paiva, Patrícia M G

    2015-08-01

    This study reports the effect of an aqueous extract from Moringa oleifera Lam. flowers on Biomphalaria glabrata embryos and adults and on Schistosoma mansoni adult worms. The extract contains tannins, saponins, flavones, flavonols, xanthones, and trypsin inhibitor activity. The toxicity of the extract on Artemia salina larvae was also investigated to determine the safety of its use for schistosomiasis control. After incubation for 24h, the flower extract significantly (poleifera flower extract had deleterious effects on B. glabrata adults and embryos. However, unrestricted use to control schistosomiasis should be avoided due to the toxicity of this extract on A. salina. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Intermediate and definitive hosts of Schistosoma mansoni in Corrientes province, Argentina

    OpenAIRE

    C Edgardo Borda; María JF Rea

    2006-01-01

    Corrientes province is located in the humid subtropical region of Argentina northeast on the left riverbank of Paraná River in the border with the South of Brazil. This is a region without schistosomiasis but planorbid and rodents that would serve as host of the life cycle of Schistosoma mansoni inhabit here. The objective of this work is to know the role of rodent as definitive host of schistosomiasis. Biomphalaria tenagophila (4 to 8 mm Ø) from Maloyas, exposed each to 10 miracidia of SJ2 s...

  6. Schistosoma mansoni cercariae exploit an elastohydrodynamic coupling to swim efficiently

    CERN Document Server

    Krishnamurthy, Deepak; Bhargava, Arjun; Prakash, Manu

    2016-01-01

    The motility of many parasites is critical for the infection process of their host, as exemplified by the transmission cycle of the blood fluke Schistosoma mansoni. In their human infectious stage, immature, submillimetre-scale forms of the parasite known as cercariae swim in freshwater and infect humans by penetrating through the skin. This infection causes Schistosomiasis, a parasitic disease that is comparable to malaria in its global socio-economic impact. Given that cercariae do not feed and hence have a finite lifetime of around 12 hours, efficient motility is crucial for the parasite's survival and transmission of Schistosomiasis. However, a first-principles understanding of how cercariae swim is lacking. Via a combined experimental, theoretical and robotics based approach, we demonstrate that cercariae propel themselves against gravity by exploiting a unique elastohydrodynamic coupling. We show that cercariae beat their tail in a periodic fashion while maintaining a fixed flexibility near their poster...

  7. A Loop-Mediated Isothermal Amplification (LAMP) Assay for Early Detection of Schistosoma mansoni in Stool Samples: A Diagnostic Approach in a Murine Model

    Science.gov (United States)

    Fernández-Soto, Pedro; Gandasegui Arahuetes, Javier; Sánchez Hernández, Alicia; López Abán, Julio; Vicente Santiago, Belén; Muro, Antonio

    2014-01-01

    Background Human schistosomiasis, mainly due to Schistosoma mansoni species, is one of the most prevalent parasitic diseases worldwide. To overcome the drawbacks of classical parasitological and serological methods in detecting S. mansoni infections, especially in acute stage of the disease, development of cost-effective, simple and rapid molecular methods is still needed for the diagnosis of schistosomiasis. A promising approach is the loop-mediated isothermal amplification (LAMP) technology. Compared to PCR-based assays, LAMP has the advantages of reaction simplicity, rapidity, specificity, cost-effectiveness and higher amplification efficiency. Additionally, as results can be inspected by the naked eye, the technique has great potential for use in low-income countries. Methodology/Principal findings A sequence corresponding to a mitochondrial S. mansoni minisatellite DNA region was selected as a target for designing a LAMP-based method to detect S. mansoni DNA in stool samples. We used a S. mansoni murine model to obtain well defined stool and sera samples from infected mice with S. mansoni cercariae. Samples were taken weekly from week 0 to 8 post-infection and the Kato-Katz and ELISA techniques were used for monitoring the infection. Primer set designed were tested using a commercial reaction mixture for LAMP assay and an in house mixture to compare results. Specificity of LAMP was tested using 16 DNA samples from different parasites, including several Schistosoma species, and no cross-reactions were found. The detection limit of our LAMP assay (SmMIT-LAMP) was 1 fg of S. mansoni DNA. When testing stool samples from infected mice the SmMIT-LAMP detected S. mansoni DNA as soon as 1 week post-infection. Conclusions/Significance We have developed, for the first time, a cost-effective, easy to perform, specific and sensitive LAMP assay for early detection of S. mansoni in stool samples. The method is potentially and readily adaptable for field diagnosis and

  8. A loop-mediated isothermal amplification (LAMP assay for early detection of Schistosoma mansoni in stool samples: a diagnostic approach in a murine model.

    Directory of Open Access Journals (Sweden)

    Pedro Fernández-Soto

    2014-09-01

    Full Text Available Human schistosomiasis, mainly due to Schistosoma mansoni species, is one of the most prevalent parasitic diseases worldwide. To overcome the drawbacks of classical parasitological and serological methods in detecting S. mansoni infections, especially in acute stage of the disease, development of cost-effective, simple and rapid molecular methods is still needed for the diagnosis of schistosomiasis. A promising approach is the loop-mediated isothermal amplification (LAMP technology. Compared to PCR-based assays, LAMP has the advantages of reaction simplicity, rapidity, specificity, cost-effectiveness and higher amplification efficiency. Additionally, as results can be inspected by the naked eye, the technique has great potential for use in low-income countries.A sequence corresponding to a mitochondrial S. mansoni minisatellite DNA region was selected as a target for designing a LAMP-based method to detect S. mansoni DNA in stool samples. We used a S. mansoni murine model to obtain well defined stool and sera samples from infected mice with S. mansoni cercariae. Samples were taken weekly from week 0 to 8 post-infection and the Kato-Katz and ELISA techniques were used for monitoring the infection. Primer set designed were tested using a commercial reaction mixture for LAMP assay and an in house mixture to compare results. Specificity of LAMP was tested using 16 DNA samples from different parasites, including several Schistosoma species, and no cross-reactions were found. The detection limit of our LAMP assay (SmMIT-LAMP was 1 fg of S. mansoni DNA. When testing stool samples from infected mice the SmMIT-LAMP detected S. mansoni DNA as soon as 1 week post-infection.We have developed, for the first time, a cost-effective, easy to perform, specific and sensitive LAMP assay for early detection of S. mansoni in stool samples. The method is potentially and readily adaptable for field diagnosis and disease surveillance in schistosomiasis-endemic areas.

  9. A Latent Markov Modelling approach to the evaluation of Circulating Cathodic Antigen strips for Schistosomiasis diagnosis pre- and post-praziquantel treatment in Uganda

    DEFF Research Database (Denmark)

    Koukounari, Artemis; Donnelly, Christl A.; Moustaki, Irini

    2013-01-01

    Markov Models (LMMs). The aim was to evaluate the diagnostic accuracy of Circulating Cathodic Antigen (CCA) and of double Kato-Katz (KK) faecal slides over three consecutive days for Schistosoma mansoni infection simultaneously by age group at baseline and at two follow-up times post treatment...... as well as CCA for mapping surveys of S. mansoni infection, although additional diagnostic tools should be incorporated in schistosomiasis elimination programs....

  10. Prevalence and associated factors of Schistosomiasis among children in Yemen: implications for an effective control programme.

    Directory of Open Access Journals (Sweden)

    Hany Sady

    Full Text Available Schistosomiasis, one of the most prevalent neglected tropical diseases, is a life-threatening public health problem in Yemen especially in rural communities. This cross-sectional study aims to determine the prevalence and associated risk factors of schistosomiasis among children in rural Yemen.Urine and faecal samples were collected from 400 children. Urine samples were examined using filtration technique for the presence of Schistosoma haematobium eggs while faecal samples were examined using formalin-ether concentration and Kato Katz techniques for the presence of S. mansoni. Demographic, socioeconomic and environmental information were collected via a validated questionnaire. Overall, 31.8% of the participants were found to be positive for schistosomiasis; 23.8% were infected with S. haematobium and 9.3% were infected with S. mansoni. Moreover, 39.5% of the participants were anaemic whereas 9.5% had hepatosplenomegaly. The prevalence of schistosomiasis was significantly higher among children aged >10 years compared to those aged ≤ 10 years (P<0.05. Multivariate analysis confirmed that presence of other infected family member (P<0.001, low household monthly income (P = 0.003, using unsafe sources for drinking water (P = 0.003, living nearby stream/spring (P = 0.006 and living nearby pool/pond (P = 0.002 were the key factors significantly associated with schistosomiasis among these children.This study reveals that schistosomiasis is still highly prevalent in Yemen. These findings support an urgent need to start an integrated, targeted and effective schistosomiasis control programme with a mission to move towards the elimination phase. Besides periodic drug distribution, health education and community mobilisation, provision of clean and safe drinking water, introduction of proper sanitation are imperative among these communities in order to curtail the transmission and morbidity caused by schistosomiasis. Screening and treating other infected

  11. African schistosomiasis in mainland China: risk of transmission and countermeasures to tackle the risk.

    Science.gov (United States)

    Wang, Wei; Liang, You-Sheng; Hong, Qing-Biao; Dai, Jian-Rong

    2013-08-28

    Schistosomiasis is a major disease of public health importance in humans occurring in 76 countries of the tropics and sub-tropics. In China, schistosomiasis japonica is one of the highest priorities in communicable disease control defined by the central government. Since 1970s, the habitats of Biomphalaria straminea, an intermediate host of Schistosoma mansoni in South America, have been identified in Hong Kong Special Administrative Region and Shenzhen city, Guangdong province of China. With the sharp growth in the China-aided projects in Africa and labor services export to Africa, a gradual rise in the cases infected with S. haematobium or S. mansoni is reported in those returning from Africa to China. The existence of intermediate snail hosts and import of infectious source of schistosomiasis results in concern about the transmission of African schistosomiasis in mainland China in the context of global climate change. This paper evaluates the risk of transmission of African schistosomiasis in China, and proposes countermeasures and research priorities to tackle the risk.

  12. CASE REPORT Cerebral schistosomiasis

    African Journals Online (AJOL)

    0b013e3182704d1e]. 5. Sanelli PC, Lev MH, Gonzalez RG, Schaefer PW. Unique linear and nodular MR enhancement pattern in schistosomiasis of the central nervous system: Report of three patients. AJR 2001;177(6):1471-1474. Cerebral schistosomiasis.

  13. Bioquímica da esquistossomose mansônica: VII. Alterações lipídicas das membranas lisossômicas durante a faze inicial da agressão hepática Biochemistry of schistosomiasis mansoni: VII. Changes of the lipid composition of lynsosomal membranes at the initialphase of liver injury

    Directory of Open Access Journals (Sweden)

    Luiz Erlon Araújo Rodrigues

    1988-03-01

    sphingomyelines increased, respectively from 58 ± 9,7 to 60 ± 8,5, from 72 ± 7,8 to 111 ± 15,7 and from 36 ± 4,9 to 63 ± 7,1 µg/mg. The free fatty acids showed no statistical significance on their variations. They varied from 1,7 ± 0,25 µEq/g in the controls to 1,8 ± 0,39 Eq/g in the infected animals. These results indicated that in the initial phase of hepatic schistosomiasis, before the formation of granulomas, important changes on the lipidic constitution of lysosomal membranes can be detected. It seems that they are provoked by the catabolic excreted by immature or adult worms of Schistosoma mansoni present in the portal vein system.

  14. Schistosomiasis research in Africa

    DEFF Research Database (Denmark)

    Utzinger, Jürg; Brattig, Norbert W.; Kristensen, Thomas K.

    2013-01-01

    , social and cross-cutting issues pertaining to the epidemiology and control of schistosomiasis. We summarize key achievements made by CONTRAST, many of which are featured in this special issue of Acta Tropica. Together with an independent view put forth by an eminent schistosomiasis researcher...... alliance to optimize schistosomiasis control and transmission surveillance in sub-Saharan Africa - was ahead of the game. Indeed, launched in October 2006, this 4-year project funded by the European Commission made important contributions for sustainable schistosomiasis control in the selected African...... countries through innovation, validation and application of new tools and locally adapted intervention strategies complementary to preventive chemotherapy. Moreover, CONTRAST articulated a research agenda for schistosomiasis elimination, framed by 10 key questions. Here, we provide a rationale for CONTRAST...

  15. Anti-inflammatory Properties Of Menthol And Menthone In Schistosoma Mansoni Infection.

    OpenAIRE

    Zaia, Mauricio G.; Cagnazzo, Túlio di Orlando; Feitosa, Karina A.; Soares,Edson G.; Faccioli, Lúcia H.; Silmara M. Allegretti; Afonso, Ana; Anibal,Fernanda de Freitas

    2016-01-01

    Schistosomiasis is a parasitic disease caused by several species of trematode worms and it is believed that more than 261 million people are affected worldwide. New drug development has become essential because there is a risk of the parasite becoming resistant to Praziquantel, the only drug available for this infection. This study evaluated parasitological, immunological and histological parameters in mice infected with Schistosoma mansoni and treated with an herbal commercial medicine. This...

  16. Histological assessment of granulomas in natural and experimental Schistosoma mansoni infections using whole slide imaging.

    Directory of Open Access Journals (Sweden)

    Kátia B Amaral

    Full Text Available The pathology of schistosomiasis mansoni, a neglected tropical disease of great clinical and socioeconomic importance, results from the parasite eggs that become trapped in host tissues, particularly in the liver and intestines. Continuous antigenic stimulation from these eggs leads to recruitment of inflammatory cells to the sites of infection with formation of periovular granulomas. These complex structures have variable size and composition and are the most striking histopathological feature of schistosomiasis mansoni. However, evaluation of granulomas by conventional microscopy methods is time-consuming and limited, especially in large-scale studies. Here, we used high resolution Whole Slide Imaging (WSI, which allows fast scanning of entire histological slides, and multiple morphometric evaluations, to assess the granulomatous response elicited in target organs (liver, small and large intestines of two models of schistosomiasis mansoni. One of the advantages of WSI, also termed virtual microscopy, is that it generates images that simultaneously offer high resolution and a wide field of observation. By using a model of natural (Nectomys squamipes, a wild reservoir captured from endemic areas in Brazil and experimental (Swiss mouse infection with Schistosoma mansoni, we provided the first detailed WSI characterization of granulomas and other pathological aspects. WSI and quantitative analyses enabled a fast and reliable assessment of the number, evolutional types, frequency and areas of granulomas and inflammatory infiltrates and revealed that target organs are differentially impacted by inflammatory responses in the natural and experimental infections. Remarkably, high-resolution analysis of individual eosinophils, key cells elicited by this helminthic infection, showed a great difference in eosinophil numbers between the two infections. Moreover, features such as the intestinal egg path and confluent granulomas were uncovered. Thus, WSI may

  17. Specific schistosomiasis treatment as a strategy for disease control

    Directory of Open Access Journals (Sweden)

    José Rodrigues Coura

    2010-07-01

    Full Text Available The great hope for schistosomiasis treatment began with the development of oxamniquine and praziquantel. These drugs can be administered orally in a single dose and have a high curative power with minor side effects. In this study, we carried out a field experiment involving a population of 3,782 people. The population was examined at four localities in Minas Gerais within the valleys of the Doce and Jequitinhonha Rivers. In this cohort, there were 1,790 patients infected with Schistosoma mansoni (47.3% and we showed that only 1,403 (78.4% could be treated with oxamniquine in a single dose of 12.5-20 mg/kg orally. The other 387 (21.6% were not treated during the first stage because of contraindications (pregnancy or impeditive diseases, absences or refusals. It was observed that, on average, 8.8-17% of the infected patients continued to excrete S. mansoni eggs at the end of the 2nd month after treatment and 30-32% of the cohort was infected by the end of the 24th month. In one of the areas that we followed-up for a total of 30 years, the prevalence of the infection with S. mansoni fell from 60.8-19.3% and the hepatosplenic form of the disease dropped from 5.8-1.3%. We conclude that specific treatment of schistosomiasis reduces the prevalence of infection in the short-term and the morbidity due to schistosomiasis in medium to long-term time frames, but does not help to control disease transmission.

  18. Cardamonin, a schistosomicidal chalcone from Piper aduncum L. (Piperaceae) that inhibits Schistosoma mansoni ATP diphosphohydrolase.

    Science.gov (United States)

    de Castro, Clarissa C B; Costa, Poliana S; Laktin, Gisele T; de Carvalho, Paulo H D; Geraldo, Reinaldo B; de Moraes, Josué; Pinto, Pedro L S; Couri, Mara R C; Pinto, Priscila de F; Da Silva Filho, Ademar A

    2015-09-15

    Schistosomiasis is one of the world's major public health problems, and praziquantel (PZQ) is the only available drug to treat this neglected disease with an urgent demand for new drugs. Recent studies indicated that extracts from Piper aduncum L. (Piperaceae) are active against adult worms of Schistosoma mansoni, the major etiological agent of human schistosomiasis. We investigated the in vitro schistosomicidal activity of cardamonin, a chalcone isolated from the crude extract of P. aduncum. Also, this present work describes, for the first time, the S. mansoni ATP diphosphohydrolase inhibitory activity of cardamonin, as well as, its molecular docking with S. mansoni ATPDase1, in order to investigate its mode of inhibition. In vitro schistosomicidal assays and confocal laser scanning microscopy were used to evaluate the effects of cardamonin on adult schistosomes. Cell viability was measured by MTT assay, and the S. mansoni ATPase activity was determined spectrophotometrically. Identification of the cardamonin binding site and its interactions on S. mansoni ATPDase1 were made by molecular docking experiments. A bioguided fractionation of the crude extract of P. aduncum was carried out, leading to identification of cardamonin as the active compound, along with pinocembrin and uvangoletin. Cardamonin (25, 50, and 100 µM) caused 100% mortality, tegumental alterations, and reduction of oviposition and motor activity of all adult worms of S. mansoni, without affecting mammalian cells. Confocal laser scanning microscopy showed tegumental morphological alterations and changes on the numbers of tubercles of S. mansoni worms in a dose-dependent manner. Cardamonin also inhibited S. mansoni ATP diphosphohydrolase (IC50 of 23.54 µM). Molecular docking studies revealed that cardamonin interacts with the Nucleotide-Binding of SmATPDase 1. The nature of SmATPDase 1-cardamonin interactions is mainly hydrophobic and hydrogen bonding. This report provides evidence for the in vitro

  19. Genetic variation between Biomphalaria alexandrina snails susceptible and resistant to Schistosoma mansoni infection.

    Science.gov (United States)

    El-Nassery, Suzanne M F; Abou-El-Naga, Iman F; Allam, Sonia R; Shaat, Eman A; Mady, Rasha F M

    2013-01-01

    Much effort has been made to control schistosomiasis infection in Egypt. However, enduring effects from such strategies have not yet been achieved. In this study, we sought to determine the genetic variability related to the interaction between Biomphalaria alexandrina snails and Schistosoma mansoni. Using RAPD-PCR with eight (10 mers) random primers, we were able to determine the polymorphic markers that differed between snails susceptible and resistant to Schistosoma mansoni infection using five primers out of the eight. Our results suggest that the RAPD-PCR technique is an efficient means by which to compare genomes and to detect genetic variations between schistosomiasis intermediate hosts. The RAPD technique with the above-noted primers can identify genomic markers that are specifically related to the Biomphalaria alexandrina/Schistosoma mansoni relationship in the absence of specific nucleotide sequence information. This approach could be used in epidemiologic surveys to investigate genetic diversity among Biomphalaria alexandrina snails. The ability to determine resistant markers in Biomphalaria alexandrina snails could potentially lead to further studies that use refractory snails as agents to control the spread of schistosomiasis.

  20. Intermediate and definitive hosts of Schistosoma mansoni in Corrientes province, Argentina

    Directory of Open Access Journals (Sweden)

    C Edgardo Borda

    2006-10-01

    Full Text Available Corrientes province is located in the humid subtropical region of Argentina northeast on the left riverbank of Paraná River in the border with the South of Brazil. This is a region without schistosomiasis but planorbid and rodents that would serve as host of the life cycle of Schistosoma mansoni inhabit here. The objective of this work is to know the role of rodent as definitive host of schistosomiasis. Biomphalaria tenagophila (4 to 8 mm Ø from Maloyas, exposed each to 10 miracidia of SJ2 strain of S. mansoni natives from Brazil were susceptible (5%. The degree of compatibility was Class II of Frandsen. Five wild rodents captured in the same ecological niche were exposed transcutaneously to infection with 40 cercariae for animal: two Olygoryzomys flavescens, two Holochilus braziliensis, and one Scapteromys tuncidus. Only one H. braziliensis eliminated eggs in feces. Prepatent period was of 83 days. With these feces, two of six (33.3% B. tenagophila from Maloyas were infected with miracidium. It was demonstrated, in an area free of schistosomiasis, that life cycle S. mansoni is closed with planorbid and rodents that live in the same ecological niche.

  1. Anti-Inflammatory Properties of Menthol and Menthone in Schistosoma mansoni Infection

    Science.gov (United States)

    Zaia, Mauricio G.; Cagnazzo, Túlio di Orlando; Feitosa, Karina A.; Soares, Edson G.; Faccioli, Lúcia H.; Allegretti, Silmara M.; Afonso, Ana; Anibal, Fernanda de Freitas

    2016-01-01

    Schistosomiasis is a parasitic disease caused by several species of trematode worms and it is believed that more than 261 million people are affected worldwide. New drug development has become essential because there is a risk of the parasite becoming resistant to Praziquantel, the only drug available for this infection. This study evaluated parasitological, immunological and histological parameters in mice infected with Schistosoma mansoni and treated with an herbal commercial medicine. This drug consists of menthol (30–55%) and menthone (14–32%). A 60 day treatment regimen with the herbal medicine decreased the number of S. mansoni eggs in the feces, liver, and intestine and reduced the number of hepatic granulomas. We observed a reduction of 84% in blood eosinophilia and a decrease in the IL-4 and IL-10 blood levels after treatment. Therefore, we propose that schistosomiasis treatment with this herbal medicine for 60 days has an immunomodulatory and anti-inflammatory action in this animal model for schistosomiasis thus contributing to the decrease in physio pathological effects caused by S. mansoni infection. PMID:27378927

  2. Genetic Variation between Biomphalaria alexandrina Snails Susceptible and Resistant to Schistosoma mansoni Infection

    Directory of Open Access Journals (Sweden)

    Suzanne M. F. El-Nassery

    2013-01-01

    Full Text Available Much effort has been made to control schistosomiasis infection in Egypt. However, enduring effects from such strategies have not yet been achieved. In this study, we sought to determine the genetic variability related to the interaction between Biomphalaria alexandrina snails and Schistosoma mansoni. Using RAPD-PCR with eight (10 mers random primers, we were able to determine the polymorphic markers that differed between snails susceptible and resistant to Schistosoma mansoni infection using five primers out of the eight. Our results suggest that the RAPD-PCR technique is an efficient means by which to compare genomes and to detect genetic variations between schistosomiasis intermediate hosts. The RAPD technique with the above-noted primers can identify genomic markers that are specifically related to the Biomphalaria alexandrina/Schistosoma mansoni relationship in the absence of specific nucleotide sequence information. This approach could be used in epidemiologic surveys to investigate genetic diversity among Biomphalaria alexandrina snails. The ability to determine resistant markers in Biomphalaria alexandrina snails could potentially lead to further studies that use refractory snails as agents to control the spread of schistosomiasis.

  3. The hepatoprotective activity of blue green algae in Schistosoma mansoni infected mice.

    Science.gov (United States)

    Mohamed, Azza H; Osman, Gamalat Y; Salem, Tarek A; Elmalawany, Alshimaa M

    2014-10-01

    This study aims to evaluate the immunomodulatory effects of a natural product, blue green algae (BGA) (100 mg/kg BW), alone or combined with praziquantel PZQ (250 mg/kg BW) on granulomatous inflammation, liver histopathology, some biochemical and immunological parameters in mice infected with Schistosoma mansoni. Results showed that the diameter and number of egg granuloma were significantly reduced after treatment of S. mansoni-infected mice with BGA, PZQ and their combination. The histopathological alterations observed in the liver of S. mansoni-infected mice were remarkably inhibited after BGA treatments. BGA decreased the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) as well as the level of total protein (TP) while the level of albumin was increased. Treatment of infected mice with BGA, PZQ as well as their combination led to significant elevation in the activities of hepatic antioxidant enzymes glutathione peroxidase (GPX) and glutathione-S-transferase (GST) as compared with control group. Combination of BGA and PZQ resulted in significant reduction in the level of intercellular adhesion molecules-1 (ICAM-1), vascular adhesion molecules-1 (VCAM-1) and tumor necrosis factor-alpha (TNF-α) when compared to those of the S. mansoni-infected group. Overall, BGA significantly inhibited the liver damage accompanied with schistosomiasis, exhibited a potent antioxidant and immunoprotective activities. This study suggests that BGA can be considered as promising for development a complementary and/or alternative medicine against schistosomiasis. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Schistosomiasis: a case of severe infection with fatal outcome

    Directory of Open Access Journals (Sweden)

    Cristiane Rúbia Ferreira

    2012-03-01

    Full Text Available Schistosomiasis is one of the most common parasitic diseases, stillconsidered of public health significance. Acute schistosomiasis is of difficultdiagnosis and therefore has been overlooked, misdiagnosed, underestimatedand underreported in endemic areas. The delay between the exposure tocontaminated water and the initial symptoms may explain this challengingdiagnosis. Acute schistosomiasis is frequently reported in non-immuneindividuals while reinfection cases occurring in endemic areas is scarcelydocumented. The later usually shows a benign course but fatal cases do exist.The authors report a case of a young female patient, in the late puerperium,with a three-month history of weight loss, intermittent fever, cough, thoracicand abdominal pain and increased abdominal girth. Physical examinationshowed a tachycardia, tachypnea and hypotension. Laboratory tests showeda mild anemia, eosinophilia, and a slightly elevation of liver enzymes. Thoraxand abdominal multidetector computed tomography evidenced a diffuseand bilateral pulmonary micronodules and peritoneal and intestinal wallthickening. The patient progressed rapidly to hepatic insufficiency, and deathafter respiratory insufficiency. An autopsy was performed and the findingswere compatible with acute Schistosomiasis in a patient previously exposedto Schistosoma mansoni.

  5. High prevalence and presumptive treatment of schistosomiasis and strongyloidiasis among African refugees.

    Science.gov (United States)

    Posey, Drew L; Blackburn, Brian G; Weinberg, Michelle; Flagg, Elaine W; Ortega, Luis; Wilson, Marianna; Secor, W Evan; Sanders-Lewis, Kolby; Won, Kimberly; Maguire, James H

    2007-11-15

    Schistosomiasis and strongyloidiasis cause substantial morbidity and mortality among hundreds of millions of infected persons worldwide. In the United States, these infections are most commonly found among international travelers, immigrants, and refugees from areas of endemicity. Refugees resettled to the United States since 2000 include >3800 "Lost Boys and Girls" of Sudan and 8000 Somali Bantu. Many Lost Boys and Girls of Sudan reported chronic abdominal pain only since arrival, and some received diagnoses of schistosomiasis or strongyloidiasis. We assessed seroprevalence of these infections among these refugees and hypothesized an association between infection and abdominal pain. We offered a survey assessing chronic abdominal pain and serologic testing for schistosomiasis and strongyloidiasis to all 800 attendees of a Lost Boys and Girls of Sudan reunion in the United States. Serologic testing was performed on preimmigration specimens obtained from 100 United States-bound Somali Bantu refugees. Of the 462 Sudanese refugees (58%) tested, 44% and 46% were seropositive for schistosomiasis (primarily due to Schistosoma mansoni) and strongyloidiasis, respectively; 24% of those who tested positive for schistosomiasis had S. mansoni antigenemia. Forty-six percent reported chronic abdominal pain, which was not associated with either infection. Among 100 Somali Bantu, 73% and 23% tested seropositive for schistosomiasis (primarily due to Schistosoma haematobium) and strongyloidiasis, respectively. The high seroprevalence of schistosomiasis and strongyloidiasis among Sudanese Lost Boys and Girls and Somali Bantu refugees supports presumptive treatment for these refugees. Current refugee resettlement policies inadequately address these diseases; our data support consideration of predeparture presumptive therapy for all refugees from areas of endemicity.

  6. Bladder morbidity and hepatic fibrosis in mixed Schistosoma haematobium and S. mansoni Infections: a population-wide study in Northern Senegal.

    NARCIS (Netherlands)

    Meurs, L.; Mbow, M.; Vereecken, K.M.; Menten, J.; Mboup, S.; Polman, K.

    2012-01-01

    Background: The global distribution map of schistosomiasis shows a large overlap of Schistosoma haematobium- and S. mansoni-endemic areas in Africa. Yet, little is known about the consequences of mixed Schistosoma infections for the human host. A recent study in two neighboring co-endemic

  7. A COMPARATIVE EPIDEMIOLOGIC STUDY OF SPECIFIC ANTIBODIES (IgM AND IgA AND PARASITOLOGICAL FINDINGS IN AN ENDEMIC AREA OF LOW TRANSMISSION OF Schistosoma mansoni

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    KANAMURA Herminia Yohko

    1998-01-01

    Full Text Available The diagnostic potential of circulating IgM and IgA antibodies against Schistosoma mansoni gut-associated antigens detected by the immunofluorescence test (IFT on adult worm paraffin sections was evaluated comparatively to the fecal parasitological method, for epidemiological purposes in low endemic areas for schistosomiasis. Blood samples were collected on filter paper from two groups of schoolchildren living in two different localities of the municipality of Itariri (São Paulo, Brazil with different histories and prevalences of schistosomiasis. The parasitological and serological data were compared to those obtained for another group of schoolchildren from a non-endemic area for schistosomiasis. The results showed poor sensitivity of the parasitological method in detecting individuals with low worm burden and indicate the potential of the serological method as an important tool to be incorporated into schistosomiasis control and vigilance programs for determining the real situation of schistosomiasis in low endemic areas.

  8. Schistosomiasis Mansoni among School Children of Different Water ...

    African Journals Online (AJOL)

    PO Box 231, Mekelle, Ethiopia (*taddej2002@gmail.com). 2Department of ... The current trend of harvesting water to supplement the agricultural productivity is associated with the expansion of ..... Reports from. Egypt had also shown an increase in prevalence from 0.05% to 60% within less than five years following the ...

  9. Primary spinal cord mansoni schistosomiasis : a case report ...

    African Journals Online (AJOL)

    The authors present the case of a 25-year-old male with a paraplegia of fluctuating character which still proved to be a diagnostic problem after investigations which included myelography, CT-myelography and magnetic resonance imaging. Laminectomy and biopsy revealed a schistosomal granuloma in the region of the ...

  10. primary spinal cord mansoni schistosomiasis : a case report

    African Journals Online (AJOL)

    The authors present the case of a 25-year-old male with a paraplegia of fluctuating character which still proved to be a diagnostic problem after investigations which included myelography, CT-myelography and magnetic resonance imaging. Laminectomy and biopsy revealed a schistosomal granuloma in the region of the ...

  11. Vaccination with Enzymatically Cleaved GPI-Anchored Proteins from Schistosoma mansoni Induces Protection against Challenge Infection

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    Vicente P. Martins

    2012-01-01

    Full Text Available The flatworm Schistosoma mansoni is a blood fluke parasite that causes schistosomiasis, a debilitating disease that occurs throughout the developing world. Current schistosomiasis control strategies are mainly based on chemotherapy, but many researchers believe that the best long-term strategy to control schistosomiasis is through immunization with an antischistosomiasis vaccine combined with drug treatment. In the search for potential vaccine candidates, numerous tegument antigens have been assessed. As the major interface between parasite and mammalian host, the tegument plays crucial roles in the establishment and further course of schistosomiasis. Herein, we evaluated the potential of a GPI fraction, containing representative molecules located on the outer surface of adult worms, as vaccine candidate. Immunization of mice with GPI-anchored proteins induced a mixed Th1/Th2 type of immune response with production of IFN-γ and TNF-α, and low levels of IL-5 into the supernatant of splenocyte cultures. The protection engendered by this vaccination protocol was confirmed by 42% reduction in worm burden, 45% reduction in eggs per gram of hepatic tissue, 29% reduction in the number of granulomas per area, and 53% reduction in the granuloma fibrosis. Taken together, the data herein support the potential of surface-exposed GPI-anchored antigens from the S. mansoni tegument as vaccine candidate.

  12. Vaccination with enzymatically cleaved GPI-anchored proteins from Schistosoma mansoni induces protection against challenge infection.

    Science.gov (United States)

    Martins, Vicente P; Pinheiro, Carina S; Figueiredo, Barbara C P; Assis, Natan R G; Morais, Suellen B; Caliari, Marcelo V; Azevedo, Vasco; Castro-Borges, William; Wilson, R Alan; Oliveira, Sergio C

    2012-01-01

    The flatworm Schistosoma mansoni is a blood fluke parasite that causes schistosomiasis, a debilitating disease that occurs throughout the developing world. Current schistosomiasis control strategies are mainly based on chemotherapy, but many researchers believe that the best long-term strategy to control schistosomiasis is through immunization with an antischistosomiasis vaccine combined with drug treatment. In the search for potential vaccine candidates, numerous tegument antigens have been assessed. As the major interface between parasite and mammalian host, the tegument plays crucial roles in the establishment and further course of schistosomiasis. Herein, we evaluated the potential of a GPI fraction, containing representative molecules located on the outer surface of adult worms, as vaccine candidate. Immunization of mice with GPI-anchored proteins induced a mixed Th1/Th2 type of immune response with production of IFN-γ and TNF-α, and low levels of IL-5 into the supernatant of splenocyte cultures. The protection engendered by this vaccination protocol was confirmed by 42% reduction in worm burden, 45% reduction in eggs per gram of hepatic tissue, 29% reduction in the number of granulomas per area, and 53% reduction in the granuloma fibrosis. Taken together, the data herein support the potential of surface-exposed GPI-anchored antigens from the S. mansoni tegument as vaccine candidate.

  13. Use of Molecular Methods for the Rapid Mass Detection of Schistosoma mansoni (Platyhelminthes: Trematoda) in Biomphalaria spp. (Gastropoda: Planorbidae).

    Science.gov (United States)

    Caldeira, Roberta Lima; Jannotti-Passos, Liana Konovaloffi; Dos Santos Carvalho, Omar

    2017-01-01

    The low stringency-polymerase chain reaction (LS-PCR) and loop-mediated isothermal amplification (LAMP) assays were used to detect the presence of S. mansoni DNA in (1) Brazilian intermediate hosts (Biomphalaria glabrata, B. straminea, and B. tenagophila) with patent S. mansoni infections, (2) B. glabrata snails with prepatent S. mansoni infections, (3) various mixtures of infected and noninfected snails; and (4) snails infected with other trematode species. The assays showed high sensitivity and specificity and could detect S. mansoni DNA when one positive snail was included in a pool of 1,000 negative specimens of Biomphalaria. These molecular approaches can provide a low-cost, effective, and rapid method for detecting the presence of S. mansoni in pooled samples of field-collected Biomphalaria. These assays should aid mapping of transmission sites in endemic areas, especially in low prevalence regions and improve schistosomiasis surveillance. It will be a useful tool to monitor low infection rates of snails in areas where control interventions are leading towards the elimination of schistosomiasis.

  14. Schistosomiasis in Malawi

    DEFF Research Database (Denmark)

    Makaula, Peter; Sadalaki, John R.; Muula, Adamson S.

    2014-01-01

    and Google Scholar using th keywords: "schistosomiasis", "Bilharzia", "Bulinus" and "Biomphalaria" in combination with "Malawi". These searche were supplemented by iterative reviews of reference lists for relevant publications in peer reviewed internationa scientific journals or other media. The recovered......Introduction: Schistosomiasis remains an important public health problem that undermines social and economi development in tropical regions of the world, mainly Sub-Saharan Africa. We are not aware of any systematic revie of the literature of the epidemiology and transmission of schistosomiasis...... in Malawi since 1985. Therefore, w reviewed the current state of knowledge of schistosomiasis epidemiology and transmission in this country an identified knowledge gaps and relevant areas for future research and research governance Methods: We conducted computer-Aided literature searches of Medline, SCOPUS...

  15. Molluscicides in schistosomiasis control

    OpenAIRE

    McCullough, F. S.; Gayral, Ph.; DUNCAN, J; Christie, J. D.

    1980-01-01

    Although mollusciciding can be a cost-effective method of controlling schistosomiasis transmission, only one organic molluscicide, niclosamide, is now being produced commercially, and only a few compounds are at present being tested in the laboratory. In future, improved cost-effective use of molluscicides will require more precise knowledge of schistosomiasis transmission patterns in each endemic area and improved application techniques. In snail control studies using controlled-release form...

  16. Susceptibility of Biomphalaria tenagophila and Biomphalaria straminea to Schistosoma mansoni infection detected by low stringency polymerase chain reaction

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    JANNOTTI-PASSOS Liana Konovaloff

    2000-01-01

    Full Text Available In order to determine Schistosoma mansoni infection rates in Biomphalaria tenagophila and B. straminea, low stringency polymerase chain reaction (LS-PCR technique was used as a complementary method to light exposure technique. LS-PCR has already been standardized in our laboratory to detect the trematode DNA in B. glabrata. Higher S. mansoni infection rates were detected using conventional method and LS-PCR. The parasite DNA profile was detected in both species after 7-day exposure to miracidia, using LS-PCR. This technique enables early detection of schistosomiasis transmission focuses, in endemic areas, before the beginning of cercariae shedding.

  17. Schistosoma mansoni infection reduces the incidence of murine cerebral malaria

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    Heyfets Alina

    2010-01-01

    Full Text Available Abstract Background Plasmodium and Schistosoma are two of the most common parasites in tropical areas. Deregulation of the immune response to Plasmodium falciparum, characterized by a Th1 response, leads to cerebral malaria (CM, while a Th2 response accompanies chronic schistosomiasis. Methods The development of CM was examined in mice with concomitant Schistosoma mansoni and Plasmodium berghei ANKA infections. The effect of S. mansoni egg antigen injection on disease development and survival was also determined. Cytokine serum levels were estimated using ELISA. Statistical analysis was performed using t-test. Results The results demonstrate that concomitant S. mansoni and P. berghei ANKA infection leads to a reduction in CM. This effect is dependent on infection schedule and infecting cercariae number, and is correlated with a Th2 response. Schistosomal egg antigen injection delays the death of Plasmodium-infected mice, indicating immune involvement. Conclusions This research supports previous claims of a protective effect of helminth infection on CM development. The presence of multiple parasitic infections in patients from endemic areas should therefore be carefully noted in clinical trials, and in the development of standard treatment protocols for malaria. Defined helminth antigens may be considered for alleviation of immunopathological symptoms.

  18. Structural studies of Schistosoma mansoni adenylate kinases

    Energy Technology Data Exchange (ETDEWEB)

    Marques, I.A. [Universidade Federal de Goias (UFG), Goiania, GO (Brazil); Pereira, H.M.; Garrat, R.C. [Universidade de Sao Paulo (USP-SC), Sao Carlos, SP (Brazil)

    2012-07-01

    Full text: Parasitic diseases are a major cause of death in developing countries, however receive little or no attention from pharmaceutical companies for the development of novel therapies. In this respect, the Center for Structural Molecular Biology (CBME) of the Institute of Physics of Sao Carlos (IFSC / USP) has developed expertise in all stages of the development of active compounds against target enzymes from parasitic diseases. The present work focuses on the adenylate kinase enzymes (ADK's) from Schistosoma mansoni. These enzymes are widely distributed and catalyze the reaction of phosphoryl exchange between nucleotides in the reaction 2ADP to ATP + AMP, which is critical for the cells life cycle. Due to the particular property of the reaction catalyzed, the ADK's are recognized as reporters of the cells energetic state, translating small changes in the balance between ATP and ADP into a large change in concentration of AMP. The genome of S. mansoni was recently sequenced by the Sanger Center in England. On performing searches for genes encoding adenylate kinases we found two such genes. The corresponding gene products were named ADK1 (197 residues) and ADK2 (239 residues), and the two sequences share only 28 percent identity. Both have been cloned into the pET-28a(+)vector, expressed in E. coli and purified. Preliminary tests of activity have been performed only for ADK1 showing it to be catalytically active. Crystallization trials were performed for both proteins and thus far, crystals of ADK1 have been obtained which diffract to 2.05 at the LNLS beamline MX2 and the structure solved by molecular replacement. Understanding, at the atomic level, the function of these enzymes may help in the development of specific inhibitors and may provide tools for developing diagnostic tests for schistosomiasis. (author)

  19. Schistosoma mansoni cercariae swim efficiently by exploiting an elastohydrodynamic coupling

    Science.gov (United States)

    Krishnamurthy, Deepak; Katsikis, Georgios; Bhargava, Arjun; Prakash, Manu

    2017-03-01

    The motility of many parasites is critical for infecting their host, as exemplified in the transmission cycle of the parasite Schistosoma mansoni. In its human infectious stage, submillimetre-scale forms of the parasite known as cercariae swim in freshwater and infect humans by penetrating the skin. This infection causes schistosomiasis, a disease comparable to malaria in global socio-economic impact. Given that cercariae do not feed and hence have a lifetime of around 12 hours, efficient motility is crucial for schistosomiasis transmission. Despite this, a first-principles understanding of how cercariae swim is lacking. Combining biological experiments, a novel theoretical model and its robotic realization, we show that cercariae use their forked tail to swim against gravity using a novel swimming gait, described here as a `T-swimmer gait'. During this gait, cercariae beat their tail periodically while maintaining an increased flexibility near their posterior and anterior ends. This flexibility allows an interaction between fluid drag and bending resistance--an elastohydrodynamic coupling, to naturally break time-reversal symmetry and enable locomotion at small length scales. Finally, we find that cercariae maintain this flexibility at an optimal regime for efficient swimming. We anticipate that our work sets the ground for linking the swimming of cercariae to disease transmission, and could potentially enable explorations of novel strategies for schistosomiasis control and prevention.

  20. The changing pattern of pathology due to Schistosoma mansoni infection

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    Zilton A. Andrade

    1985-09-01

    Full Text Available A survey of the autopsy data on hepatosplenic schistosomiasis during periods, before and after the advent of new chemotherapeutic drugs, revealed that: a the pathological presentation was the same for the two periods; b the number of cases in the last five years is progressively decreasing; c hepatosplenic disease due to schistosomiasis is becoming rare in young people. These data represent a change in the pattern of pathology in schistosomiasis, probably related to new chemotherapy.Uma revisão dos dados de necrópsias realizadas em portadores da forma hépato-esplênica da esquistossomose, feita em dois períodos, antes e após a introdução das novas e efetivas drogas contra o S. mansoni, revelou que: a as lesões encontradas foram qualitativamente as mesmas nos dois períodos; b a percentagem dos casos hépato-esplênicos mostra decréscimo progressivo nos últimos cinco anos do estudo; c os casos de esquistossomose hépato-esplênica estão se tornando raros em jovens. Tais elementos constituem uma mudança no padrão de apresentação da doença, possivelmente relacionada com a introdução da nova quimioterapia curativa.

  1. Increased IL-17, a Pathogenic Link between Hepatosplenic Schistosomiasis and Amyotrophic Lateral Sclerosis: A Hypothesis

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    Oswald Moling

    2014-01-01

    Full Text Available The immune system protects the organism from foreign invaders and foreign substances and is involved in physiological functions that range from tissue repair to neurocognition. However, an excessive or dysregulated immune response can cause immunopathology and disease. A 39-year-old man was affected by severe hepatosplenic schistosomiasis mansoni and by amyotrophic lateral sclerosis. One question that arose was, whether there was a relation between the parasitic and the neurodegenerative disease. IL-17, a proinflammatory cytokine, is produced mainly by T helper-17 CD4 cells, a recently discovered new lineage of effector CD4 T cells. Experimental mouse models of schistosomiasis have shown that IL-17 is a key player in the immunopathology of schistosomiasis. There are also reports that suggest that IL-17 might have an important role in the pathogenesis of amyotrophic lateral sclerosis. It is hypothesized that the factors that might have led to increased IL-17 in the hepatosplenic schistosomiasis mansoni might also have contributed to the development of amyotrophic lateral sclerosis in the described patient. A multitude of environmental factors, including infections, xenobiotic substances, intestinal microbiota, and vitamin D deficiency, that are able to induce a proinflammatory immune response polarization, might favor the development of amyotrophic lateral sclerosis in predisposed individuals.

  2. Schistosomiasis transmission at high altitude crater lakes in Western Uganda

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    Philbert Clouds

    2008-08-01

    Full Text Available Abstract Background Contrary to previous reports which indicated no transmission of schistosomiasis at altitude >1,400 m above sea level in Uganda, in this study it has been established that schistosomiasis transmission can take place at an altitude range of 1487–1682 m above sea level in western Uganda. Methods An epidemiological survey of intestinal schistosomiasis was carried out in school children staying around 13 high altitude crater lakes in Western Uganda. Stool samples were collected and then processed with the Kato-Katz technique using 42 mg templates. Thereafter schistosome eggs were counted under a microscope and eggs per gram (epg of stool calculated. A semi-structured questionnaire was used to obtain demographic data and information on risk factors. Results 36.7% of the pupils studied used crater lakes as the main source of domestic water and the crater lakes studied were at altitude ranging from 1487–1682 m above sea level. 84.6% of the crater lakes studied were infective with over 50% of the users infected. The overall prevalence of Schistosoma mansoni infection was 27.8% (103/370 with stool egg load ranging from 24–6048 per gram of stool. 84.3%( 312 had light infections (400 egg/gm of stool. Prevalence was highest in the age group 12–14 years (49.5% and geometric mean intensity was highest in the age group 9–11 years (238 epg. The prevalence and geometric mean intensity of infection among girls was lower (26%; 290 epg compared to that of boys (29.6%; 463 epg (t = 4.383, p Conclusion and recommendations The altitudinal threshold for S. mansoni transmission in Uganda has changed and use of crater water at an altitude higher than 1,400 m above sea level poses a risk of acquiring S. mansoni infection in western Uganda. However, further research is required to establish whether the observed altitudinal threshold change is as a result of climate change or other factors. It is also necessary to establish the impact this could

  3. Tandem repeat recombinant proteins as potential antigens for the sero-diagnosis of Schistosoma mansoni infection.

    Science.gov (United States)

    Kalenda, Yombo Dan Justin; Kato, Kentaro; Goto, Yasuyuki; Fujii, Yoshito; Hamano, Shinjiro

    2015-12-01

    The diagnosis of schistosome infection, followed by effective treatment and/or mass drug administration, is crucial to reduce the disease burden. Suitable diagnostic tests and field-applicable tools are required to sustain schistosomiasis control programs. We therefore assessed the potential of tandem repeat (TR) proteins for sero-diagnosis of Schistosoma mansoni infection using an experimental mouse model. TR genes in the genome of S. mansoni were searched in silico and 7 candidates, named SmTR1, 3, 8, 9, 10, 11 and 15, were selected. Total RNA was extracted from S. mansoni adult worms and eggs. Target TR genes were amplified, cloned, and the proteins were expressed in Escherichia coli competent cells. Female BALB/c mice were infected with 100 S. mansoni cercariae and sera were collected each week post-infection for 18 weeks. The levels of IgG antibodies to SmTR antigens were compared to those to soluble egg antigen (SEA) and to soluble worm antigen preparation (SWAP). Sera of infected mice reacted to all the antigens whereas those of naïve mice did not. IgG responses to SmTR1, 3, 9 and 10 were detected at the early stage of infection. Interestingly, antibodies reacting to SmTR3, 9, 10 and 15 dramatically decreased 4 weeks after treatment with praziquantel, while those against SEA and SWAP remained elevated. Our study suggests that TR proteins, especially SmTR10, may be suitable antigens for sero-diagnosis of infection by S. mansoni and are potential markers for monitoring and surveillance of schistosomiasis, including re-infection after treatment with praziquantel. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  4. Further evaluation of an updated PCR assay for the detection of Schistosoma mansoni DNA in human stool samples.

    Science.gov (United States)

    Gomes, Luciana I; Marques, Letícia H S; Enk, Martin J; Coelho, Paulo Marcos Z; Rabello, Ana

    2009-12-01

    A previously reported sensitive PCR assay for the detection of Schistosoma mansoni DNA was updated and evaluated. Changes in the DNA extraction method, including the use of a worldwide available commercial kit and the inclusion of additional quality control measures, increased the robustness of the test, as confirmed by the analysis of 67 faecal samples from an endemic area in Brazil. The PCR assay is at hand as a proven, reliable diagnostic test for the control of schistosomiasis in specific settings.

  5. Novel Therapeutic and Prevention Approaches for Schistosomiasis: Review

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    Rashika A.F. El Ridi

    2013-09-01

    Full Text Available Schistosomiasis is a debilitating disease affecting approximately 600 million people in 74 developing countries, with 800 million, mostly children at risk. To circumvent the threat of having praziquantel (PZQ as the only drug used for treatment, several PZQ derivatives were synthesized, and drugs destined for other parasites were used with success. A plethora of plant-derived oils and extracts were found to effectively kill juvenile and adult schistosomes, yet none was progressed to pre- and clinical studies except an oleo-gum resin extracted from the stem of Commiphora molmol, myrrh, which action was challenged in several trials. We have proposed an essential fatty acid, a component of our diet and cells, the polyunsaturated fatty acid arachidonic acid (ARA as a remedy for schistosomiasis, due to its ability to activate the parasite tegument-bound neutral sphingomyelinase, with subsequent hydrolysis of the apical lipid bilayer sphingomyelin molecules, allowing access of specific antibody molecules, and eventual worm attrition. This concept was convincingly supported using larval and adult Schistosoma mansoni and Schistosoma haematobium worms in in vitro experiments, and in vivo studies in inbred mice and outbred hamsters. Even if ARA proves to be an entirely effective and safe therapy for schistosomiasis, it will not prevent reinfection, and accordingly, the need for developing an effective vaccine remains an urgent priority. Our studies have supported the status of S. mansoni calpain, glutathione-S-transferase, aldolase, triose phosphate isomerase, glyceraldehyde 3-phosphate dehydrogenase, enolase, and 2-cys peroxiredoxin as vaccine candidates, as they are larval excreted-secreted products and, contrary to the surface membrane molecules, are entirely accessible to the host immune system effector elements. We have proposed that the use of these molecules, in conjunction with Th2 cytokines-inducing adjuvants for recruiting and activating

  6. Malacological assessment and natural infestation of Biomphalaria straminea (Dunker, 1848 by Schistosoma mansoni (Sambon, 1907 and Chaetogaster limnaei (K. von Baer, 1827 in an urban eutrophic watershed

    Directory of Open Access Journals (Sweden)

    M. Callisto

    Full Text Available The objective of this study was to perform a malacological assessment at the Ibirité reservoir watershed in the metropolitan region of Belo Horizonte (Minas Gerais and to evaluate the natural infestation rate of Biomphalaria straminea (Gastropoda: Planorbidaeby Schistosoma mansoni (Platyhelminthes: Trematoda and Chaetogaster limnaei (Oligochaeta: Naididae. The samples were collected from July to August 2002. The B. straminea individuals collected were kept in the laboratory; the natural infestation rate by S. mansoni and C. limnaei was assessed weekly. The malacological assessment identified fivemollusk species present in the Ibirité reservoir watershed: B. straminea, Physa marmorata, Lymnea sp., Melanoides tuberculatus,and Pomacea austrum. Laboratory observations showed that the B. straminea individuals were infected by C. limnaei rather than S. mansoni. Although there was no infection of B. straminea by S. mansoni,presence of B. straminea in itself merits close attention due to possible risk of human schistosomiasis by the local population.

  7. S. mansoni bolsters anti-viral immunity in the murine respiratory tract.

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    Sebastian Scheer

    Full Text Available The human intestinal parasite Schistosoma mansoni causes a chronic disease, schistosomiasis or bilharzia. According to the current literature, the parasite induces vigorous immune responses that are controlled by Th2 helper cells at the expense of Th1 helper cells. The latter cell type is, however, indispensable for anti-viral immune responses. Remarkably, there is no reliable literature among 230 million patients worldwide describing defective anti-viral immune responses in the upper respiratory tract, for instance against influenza A virus or against respiratory syncitial virus (RSV. We therefore re-examined the immune response to a human isolate of S. mansoni and challenged mice in the chronic phase of schistosomiasis with influenza A virus, or with pneumonia virus of mice (PVM, a mouse virus to model RSV infections. We found that mice with chronic schistosomiasis had significant, systemic immune responses induced by Th1, Th2, and Th17 helper cells. High serum levels of TNF-α, IFN-γ, IL-5, IL-13, IL-2, IL-17, and GM-CSF were found after mating and oviposition. The lungs of diseased mice showed low-grade inflammation, with goblet cell hyperplasia and excessive mucus secretion, which was alleviated by treatment with an anti-TNF-α agent (Etanercept. Mice with chronic schistosomiasis were to a relative, but significant extent protected from a secondary viral respiratory challenge. The protection correlated with the onset of oviposition and TNF-α-mediated goblet cell hyperplasia and mucus secretion, suggesting that these mechanisms are involved in enhanced immune protection to respiratory viruses during chronic murine schistosomiasis. Indeed, also in a model of allergic airway inflammation mice were protected from a viral respiratory challenge with PVM.

  8. A very high infection intensity of Schistosoma mansoni in a Ugandan Lake Victoria Fishing Community is required for association with highly prevalent organ related morbidity.

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    Edridah M Tukahebwa

    Full Text Available In schistosomiasis control programmes using mass chemotherapy, epidemiological and morbidity aspects of the disease need to be studied so as to monitor the impact of treatment, and make recommendations accordingly. These aspects were examined in the community of Musoli village along Lake Victoria in Mayuge district, highly endemic for Schistosoma mansoni infection.A cross sectional descriptive study was undertaken in a randomly selected sample of 217 females and 229 males, with a mean age of 26 years (SD ± 16, range 7-76 years. The prevalence of S. mansoni was 88.6% (95% CI: 85.6-91.5. The geometric mean intensity (GMI of S. mansoni was 236.2 (95% CI: 198.5-460.9 eggs per gram (epg faeces. Males had significantly higher GMI (370.2 epg than females (132.6 epg and age was also significantly associated with intensity of infection. Levels of water contact activities significantly influenced intensity of infection and the highest intensity of infection was found among people involved in fishing. However, organomegaly was not significantly associated with S. mansoni except for very heavy infection (>2000 epg. Liver image patterns C and D indicative of fibrosis were found in only 2.2% and 0.2%, respectively. S. mansoni intensity of infection was associated with portal vein dilation and abnormal spleen length. Anaemia was observed in 36.4% of the participants but it was not associated with S. mansoni infection intensity. Considering growth in children as one of the morbidity indicators of schistosomiasis, intensity of S. mansoni was significantly associated with stunting.Although organ-related morbidity, with the exception of periportal fibrosis, and S. mansoni infections were highly prevalent, the two were only associated for individuals with very high infection intensities. These results contrast starkly with reports from Ugandan Lake Albert fishing communities in which periportal fibrosis is more prevalent.

  9. High burden of Schistosoma mansoni infection in school-aged children in Marolambo District, Madagascar.

    Science.gov (United States)

    Spencer, Stephen A; Penney, James M St John; Russell, Hannah J; Howe, Anthony P; Linder, Cortland; Rakotomampianina, Andriamahitsisambatra L D; Nandimbiniaina, Anjara M; Squire, S Bertel; Stothard, J Russell; Bustinduy, Amaya L; Rahetilahy, Alain M

    2017-06-24

    A school-based survey was undertaken to assess prevalence and infection intensity of schistosomiasis in school-aged children in the Marolambo District of Madagascar. School-aged children from six purposively selected schools were tested for Schistosoma haematobium by urine filtration and Schistosoma mansoni using circulating cathodic antigen (CCA) and Kato-Katz stool analysis. The investigators did not address soil-transmitted helminths (STH) in this study. Of 399 school-aged children screened, 93.7% were infected with S. mansoni based on CCA analysis. Kato-Katz analysis of stool revealed S. mansoni infection in 73.6% (215/ 292). Heavy infections (> 400 eggs per gram) were common (32.1%; 69/ 215), with a mean of 482 eggs per gram of stool. Moderate infection intensities were detected in 31.2% (67/ 215) and light infection intensities in 36.7% (79/ 215) of infected participants. No infection with S. haematobium was detected by urine filtration. Intestinal schistosomiasis appears a considerable public health issue in this remote area of Madagascar where there is a pressing need for mass drug administration.

  10. Esquistossomose mansônica. I - evolução do quadro patológico: análise parasitológica, hematológica e histopatológica Schistosomiasis mansoni. I - evolution of the pathologic picture: parasitologic, hematologic, and histopathologic analyses

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    Ajax Mercês Atta

    1981-02-01

    Full Text Available Com o objetivo de acompanhar a evolução da infecção bissexual primária de camundongos por S. mansoni, foram infectados camundongos Swiss com 100 cercárias da linhagem mineira (BH de Schistosoma mansoni. A evolução da infecção foi acompanhada por um período de 8 semanas. Foi verificada uma relação entre o número de granulomas hepáticos e o número de vermes totais. O ganho de peso corporal, o peso do baço e a percentagem do peso do fígado em relação ao peso corporal foram diferentes quando comparados os animais infectados e controles. O quadro leucocitário dos camundongos infectados apresentou alterações no número de leucócitos totais, neutrófilos e linfócitos. Os exames histológicos do baço e do fígado revelaram alterações nestes órgãos de acordo com a fase da infecção.In order to accompany the evolution of primary bisexual inifection of mice by Schistosoma mansoni, Swiss mice were infected with 100 cercariae of the Belo Horizonte strain of Schistosoma mansoni, and the infection's evolution was followed for eight weeks. A relationship between the number of hepatic granulomas and the number of worms was verified. Body weight gain, spleen, and the percentage of the liver weight in relation to body weight were different when compared to infected and control animals. White blood cells in the infected mice presented alterations in the total number of leukocytes, neutrophils, and lymphocytes. The histologic analyses of the spleen and liver revealed alterations in these organs; these alterations varied according to the stage of infection.

  11. Schistosomiasis control in Brazil

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    Katz Naftale

    1998-01-01

    Full Text Available In 1975 the Special Programme for Schistosomiasis Control was introduced in Brazil with the objective of controlling this parasitic disease in six northeastern states. The methodology applied varied largely from state to state, but was based mainly on chemotherapy, This Programme was modified about ten years after it beginning with the main goals including control of morbidity and the blockage of establishment of new foci in non-endemic areas. In two states, Bahia and Minas Gerais, the schistosomiasis control programme started in 1979 and 1983, respectively. The recently made evaluation of those two programmes is the main focus of this paper. It must also be pointed out, that the great majority of the studies performed by different researchers in Brazil, at different endemic areas, consistently found significant decrease on prevalence and incidence, when control measures are repeatedly used for several years. Significant decrease of hepatosplenic forms in the studied areas is well documented in Brazil. After more than 20 years of schistosomiasis control programmes in our country, chemotherapy has shown to be a very important tool for the control of morbidity and to decrease prevalence and incidence in endemic areas. Nevertheless, in medium and long terms, sanitation, water supply, sewage draining and health education seem to be the real tools when the aim is persistent and definitive schistosomiasis control.

  12. Control of schistosomiasis transmission

    Directory of Open Access Journals (Sweden)

    Luiz C. de S. Dias

    1995-04-01

    Full Text Available Despite the success of control programmes, schistosomiasis is still a serious public health problem in the world. More than 70 countries where 200 million individuals are evaluated to be infected of a total 600 million at risk. Though there have been important local success in the control of transmission, globally the infection has increased. Economic constrains in developing countries, environmental changes associated with migration and water resources development have been blocking the progress. The main objective of schistosomiasis control is to achieve reduction of disease due to schistosomiasis. We discussed the control measures like: health education, diagnosis and chemotherapy, safe water supplies, sanitation and snail control. We emphasized the need to give priority to school-age children and the importance of integrating the measures of control into locally available systems of health care. The control of schistosomiasis is directly related to the capacity of the preventive health services of an endemic country. The strategy of control requires long-term commitment from the international to the local level.

  13. implications for schistosomiasis control

    African Journals Online (AJOL)

    of adult and 26% school children could relate hematuria to wading, a common means of exposure to urinary schistosomiasis. More than half ... energy malnutrition, and reduced mental and physiological performance [2]. Control measures ..... performance in Guatemala. Transactions of the Royal Society of Tropical Medicine ...

  14. Schistosomiasis control in China

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    Hong-Chang Yuan

    1995-04-01

    Full Text Available After three decades' efforts, schistosomiasis japonica were controlled in one-third (4/12 of endemic provinces and 68.2 (259/380 of endemic counties throughout the country. The remaining 121 endemic counties are located primarily in the lake and mountainous regions. The epidemiological and ecological features of the lake and mountainous areas are different from the other endemic areas. The major schistosomiasis control efforts in China can be characterized as follows: (1 Application of centralized leadership and management, since schistosomiasis control is a task not only of the Ministry of Public Health, but also of all local governments in the endemic areas; (2 Integration of actions taken by various departments or bureaus, such as agriculture, water conservation and public health; (3 Promotion of mass participation; (4 Organization of strong professional teams; (5 Raising sufficient funds. Strategies on schistosomiasis control applied in different areas are divided into three levels: (1 In the areas where the schistosomiasis has been successfully controlled, surveillance must be maintained and immediate action should be taken where new infections occur and/or vector snails are found, so that control can be reestablished quickly; (2 In the areas where schistosomiasis has been partially controlled, any residents and/or live-stock infected should be examined and treated promptly with due care, and environment modifying and/or mollusciding must be used to eliminate the remaining snails; (3 In the areas where transmission has not been controlled, the main strategy is to control morbidity. Mass or selective chemotherapy with praziquental should be applied to both infected persosns and the live-stock, and environment modification for the snail-ridden areas should be taken but should be coordinated with agriculture where possible. Advance cases must be treated; and epidemics of Katayama fever prevented; water supply and sanitation shoud be improved

  15. [Schistosomiasis due to Schistosoma intercalatum and urbanization in central Africa].

    Science.gov (United States)

    Ripert, C

    2003-08-01

    The species name of Schistosoma intercalatum, Fischer 1934 is linked to the shape and the size of his eggs, which are intermediate between those of S. haematobium and S. bovis. S. intercalatum is the instrument of an intestinal form of schistosomiasis looking like the form induced by S. mansoni but characterized by a low location of the lesions, mainly situated at the rectum and sigmoid level. The spreading area of S. intercalatum is bound to Central Africa. The foci are often urban and of a size limited to a town district. Bulinus forskalii is the intermediate host mostly involved in transmitting S. intercalatum lower Guinea strain, which is the strain found in the largest number of foci. B. crystallinus too transmits the parasite in the area of Gamba in Gabon. The Central Basin congolese strain of S. intercalatum is transmitted by Bulinus globosus. The houses where inhabitants are voiding eggs of S. intercalatum are just in front of the river bank or stream which are snails'breeding places. S. intercalatum is expending at the present time because of the development of built-up areas which are characterized by a disorganized town-planning. The disease is due to the high faecal pollution of the environment, causing a contamination of the urban hydrographic network which is the setting of schistosomiasis transmission. Although primely linked to the forest area, S. intercalatum is spreading with deforestation. Coming from the savannah area, S. haematobium is now invading the forest area, entering into competition with S. intercalatum. But since Bulinus acting as intermediate hosts of S. haematobium are more heliophilous than Bulinus transmitting S. intercalatum, urinary schistosomiasis has a tendency to supplant recto-sigmoidal schistosomiasis, especially in foci where hybridization between the two species of schistosomes is occurring.

  16. Chemotherapeutic Studies on Schistosomiasis.

    Science.gov (United States)

    1978-10-01

    Guide for the Care and Use of Laboratory Animals ” , DHEW Publication Num- ber ( NIH ) 73-23; as prepared by the Institute of Laboratory Animal Resour ces...Colony . The Rionipha laria qiabrata (Paulista ~ Strain) snail colony continues to provide Schistosoma mansoni cercar iae in sufficient quantities...reduced number of experimental compounds per test run. Addi- tional ly, the reduced numbers of animals provided the opportunity to perform other

  17. Morbidity due to Schistosoma mansoni--Entamoeba histolytica coinfection in hamsters (Mesocricetus auratus).

    Science.gov (United States)

    Dolabella, Silvio Santana; Coelho, Paulo Marcos Zech; Borçari, Izabela Torquetti; Mello, Nelson Azevedo Santos Teixeira; Andrade, Zilton de Araújo; Silva, Edward Felix

    2007-01-01

    Data on Schistosoma mansoni-Entamoeba histolytica coinfection are scarce in the literature. In the present study, hamsters that had been infected for 70 days with Schistosoma mansoni (LE strain) were inoculated via the portal vein with two strains of trophozoites of Entamoeba histolytica: ICB-EGG (highly virulent) and ICB-RPS (non-virulent). The most evident result of coinfection was increased morbidity and mortality, in comparison with either of the infections alone. Histologically, there were no evident signs of interaction between these two infections. The morphological findings of schistosomal granuloma and amoebic abscesses in the liver were similar to those seen in the respective single-infection controls. However, there was severe wasting of the animals with both infections and greater numbers of amoebic lesions in their livers. The results obtained indicated that schistosomiasis aggravates the course of amoebiasis in hamsters.

  18. Microgeographical and tribal variations in water contact and Schistosoma mansoni exposure within a Ugandan fishing community.

    Science.gov (United States)

    Pinot de Moira, Angela; Fulford, Anthony J C; Kabatereine, Narcis B; Kazibwe, Francis; Ouma, John H; Dunne, David W; Booth, Mark

    2007-06-01

    To explore patterns of water contact and Schistosoma mansoni exposure by age, sex, tribe and space within a single village. For 10 months, we systematically observed water contacts made by the 800 inhabitants of a small Ugandan fishing village. In order to estimate cercarial exposure, times spent in water were weighted by snail infection levels, time of day and degree of immersion. There were marked differences in water contact patterns between the two main tribes, which inhabited geographically distinct ends of the village resulting in geographically distinct spatial patterns of water contact. The distributions of the intermediate hosts, Biomphalaria sudanica and Biomphalaria stanleyi, also appeared to differ over small distances. This led to quite different exposure patterns between the two tribes, particularly amongst females. Schistosoma mansoni exposure can vary markedly within a single village. Such non-homogenous patterns of exposure are likely to have wider implications for schistosomiasis control programmes and research studies.

  19. Schistosoma mansoni Infection and Associated Determinant Factors among School Children in Sanja Town, Northwest Ethiopia

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    Ligabaw Worku

    2014-01-01

    Full Text Available Background. Intestinal schistosomiasis is one of the most widespread parasitic infections in tropical and subtropical countries. Objective. To determine the prevalence of S. mansoni infection and associated determinant factors among school children in Sanja Town, northwest Ethiopia. Methods. A cross-sectional study was conducted from February to March, 2013. 385 school children were selected using stratified proportionate systematic sampling technique. Pretested questionnaire was used to collect sociodemographic data and associated determinant factors. Stool samples were examinedusing formol-ether concentration and Kato-Katz technique. Data were entered and analyzed using SPSS 20.0 statistical software. Multivariate logistic regression was done for assessing associated risk factors and proportions for categorical variables were compared using chi-square test. P values less than 0.05 were taken as statistically significant. Results. The prevalence of S. mansoni infection was 89.9% (n=346. The overall helminthic infection in this study was 96.6% (n=372. Swimming in the river, washing clothes and utensil using river water, crossing the river with bare foot, and fishing activities showed significant association with the occurrence of S. mansoni infection. Conclusion. Schistosoma mansoni infection was high in the study area. Therefore, mass deworming at least twice a year and health education for community are needed.

  20. Hybridism between Biomphalaria cousini and Biomphalaria amazonica and its susceptibility to Schistosoma mansoni

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    Tatiana Maria Teodoro

    2011-11-01

    Full Text Available Molecular techniques can aid in the classification of Biomphalaria species because morphological differentiation between these species is difficult. Previous studies using phylogeny, morphological and molecular taxonomy showed that some populations studied were Biomphalaria cousini instead of Biomphalaria amazonica. Three different molecular profiles were observed that enabled the separation of B. amazonica from B. cousini. The third profile showed an association between the two and suggested the possibility of hybrids between them. Therefore, the aim of this work was to investigate the hybridism between B. cousini and B. amazonica and to verify if the hybrids are susceptible to Schistosoma mansoni. Crosses using the albinism factor as a genetic marker were performed, with pigmented B. cousini and albino B. amazonica snails identified by polymerase chain reaction-restriction fragment length polymorphism. This procedure was conducted using B. cousini and B. amazonica of the type locality accordingly to Paraense, 1966. In addition, susceptibility studies were performed using snails obtained from the crosses (hybrids and three S. mansoni strains (LE, SJ, AL. The crosses between B. amazonica and B. cousini confirmed the occurrence of hybrids. Moreover, hybrids can be considered potential hosts of S. mansoni because they are susceptible to LE, SJ and AL strains (4.4%, 5.6% and 2.2%, respectively. These results indicate that there is a risk of introducing schistosomiasis mansoni into new areas.

  1. The association of Schistosoma mansoni infection with hepatocellular carcinoma

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    Fausto Edmundo Lima Pereira

    1984-06-01

    Full Text Available The association of Schistosoma mansoni infection with hepatocellular carcinoma (HCC was studied in Espirito Santo State, Brazil. Schistosoma infection was diagnosed by stool examinations or by histological finding at autopsy. HCC was diagnosed by biopsy, laparoscopy and biopsy or at autopsy. Among 45 cases of HCC six had Schistosoma mansoni infection (13.04%. The occurrence of Schistosoma infection among HCC HBs Ag positive or negative was similar (13.3 3% and 13.63% respectively. The chi squared comparison showed no significant differences between the frequency of schistosomiasis in patients with HCC and the frequency of Schistosoma infection among people living in the Espirito Santo State (5.9% among children of elementary school from all the counties of the State and 6.7% in people that attended medical care in Vitoria, the capital of the State. Therefore, the authors believe that the association of schistosomiasis mansoni with HCC may be casual, specially in areas where the Schistosoma mansoni infection is frequent.Foi estudada a associação de infecção pelo Schistosoma mansoni em pacientes portadores de carcinoma hepatocelular (CHC diagnosticados no Espírito Santo. O diagnóstico de esquistossomosefoi feito pelo exame parasitológico das fezes ou pelos achados histológicos à necrópsia. O diagnóstico de CHC foi feito por laparoscopia e biópsia, somente biópsia ou por necrópsia. Entre 45 casos de CHC, seis apresentavam infecção pelo S. mansoni (13,04%. A ocorrência de infecção esquistossomótica nos CHC HBsAg positivos ou negativos foi semelhante (13,33 e 13,63% respectivamente. A comparação pelo método do qui quadrado não mostrou diferença significativa entre a freqüência de infeccção esquistossomótica nos pacientes com CHC e a freqüência de esquistossomose na população que vive no E. Santo (5,97% entre crianças do curso primário de todas as regiões do Estado e 6,75% entre a população que procura recursos m

  2. Malnutrition and hepatic fibrosis in murine schistosomiasis

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    Eridan M Coutinho

    2004-08-01

    Full Text Available In this paper, four different approaches attempting to reproduce the schistosomal liver fibrosis in undernourished mice are reported: shifting from a deficient to a balanced diet and vice-versa, repeated infections, influence of the genetic background, and immunological response. Infections were performed with 30 cercariae of Schistosoma mansoni and lasted at least four months. Undernourished mice were unable to reproduce the picture of "pipestem" fibrosis, except the C57 BL/10 inbred strain, four out of 21 mice developing the liver lesion. A link of this histological finding to the type of parasite strain can not be discarded at the moment. Repeated infections increased collagen deposition mainly in well nourished animals (seven out of 16 Swiss mice developed "pipestem"-like fibrosis. In undernourished infected Swiss mice the serum levels of soluble egg antigen specific antibodies IgG1, IgG2a, IgG2b, and IgG3 were two to four times lower than those detected for well nourished controls. The decreased humoral immune response coupled to the morphological, morphometric, and biochemical results reinforce the influence of the host nutritional status on the connective tissue changes of hepatic schistosomiasis.

  3. Studies on heterologous immunity in schistosomiasis

    Science.gov (United States)

    Massoud, J.; Nelson, G. S.

    1972-01-01

    Experiments were carried out in mice, cattle, and sheep to investigate the possibility that heterologous immune reactions may occur between the schistosomes prevalent in man and domestic animals in Iran. Immunization with Ornithobilharzia turkestanicum from cattle produced a considerable degree of immunity in mice against challenge with Schistosoma bovis, S. haematobium, and S. mansoni. The results of immunizing cattle with O. turkestanicum, S. bovis, and S. haematobium were even more striking; there was a reduction of 30-40% in the number of adult worms and a proportionally greater reduction in the tissue egg counts. Sheep developed a less marked immunity. Supplementary experiments on homologous immunity showed that mice developed a considerable degree of immunity against S. bovis. The results of the heterologous immunity experiments with S. haematobium and S. bovis are of particular interest as both parasites often occur in the same area and are often transmitted by the same snail host, man and cattle being exposed to the cercariae of both species simultaneously. The reciprocal immunity produced by these infections may be mutually beneficial in limiting the severity of schistosomiasis in man and domestic animals in the endemic areas. PMID:4540679

  4. Serological Screening of the Schistosoma mansoni Adult Worm Proteome

    Science.gov (United States)

    Ludolf, Fernanda; Patrocínio, Paola R.; Corrêa-Oliveira, Rodrigo; Gazzinelli, Andréa; Falcone, Franco H.; Teixeira-Ferreira, André; Perales, Jonas; Oliveira, Guilherme C.; Silva-Pereira, Rosiane A.

    2014-01-01

    Background New interventions tools are a priority for schistosomiasis control and elimination, as the disease is still highly prevalent. The identification of proteins associated with active infection and protective immune response may constitute the basis for the development of a successful vaccine and could also indicate new diagnostic candidates. In this context, post-genomic technologies have been progressing, resulting in a more rational discovery of new biomarkers of resistance and antigens for diagnosis. Methodology/Principal Findings Two-dimensional electrophoresed Schistosoma mansoni adult worm protein extracts were probed with pooled sera of infected and non-infected (naturally resistant) individuals from a S. mansoni endemic area. A total of 47 different immunoreactive proteins were identified by mass spectrometry. Although the different pooled sera shared most of the immunoreactive protein spots, nine protein spots reacted exclusively with the serum pool of infected individuals, which correspond to annexin, major egg antigen, troponin T, filamin, disulphide-isomerase ER-60 precursor, actin and reticulocalbin. One protein spot, corresponding to eukaryotic translation elongation factor, reacted exclusively with the pooled sera of non-infected individuals living in the endemic area. Western blotting of two selected recombinant proteins, major egg antigen and hemoglobinase, showed a similar recognition pattern of that of the native protein. Concluding/Significance Using a serological proteome analysis, a group of antigens related to the different infection status of the endemic area residents was identified and may be related to susceptibility or resistance to infection. PMID:24651847

  5. Inheritance of Schistosoma mansoni infection incompatibility in Biomphalaria alexandrina snails

    Directory of Open Access Journals (Sweden)

    Iman F Abou El Naga

    2010-03-01

    Full Text Available In this study, we looked at the inheritance of susceptibility and resistance to Schistosoma mansoni infection in the first generation of crossbred Biomphalaria alexandrina snails. Our ultimate goal is to use such information to develop a biological method of controlling schistosomiasis. We infected laboratory-bred snails with S. mansoni miracidia and examined cercarial shedding to determine susceptibility and resistance. Five parental groups were used: Group I contained 30 susceptible snails, Group II contained 30 resistant snails, Group III contained 15 susceptible and 15 resistant snails, Group IV contained 27 susceptible and three resistant snails and Group V contained three susceptible and 27 resistant snails. The percentage of resistant snails in the resulting progeny varied according to the ratio of susceptible and resistant parents per group; they are 7%, 100%, 68%, 45% and 97% from Groups I, II, III, IV and V, respectively. On increasing the percentage of resistant parent snails, the percentage of resistant progeny increased, while cercarial production in their susceptible progeny decreased.

  6. Basophil depletion downregulates Schistosoma mansoni egg-induced granuloma formation.

    Science.gov (United States)

    Anyan, William K; Seki, Takenori; Kumagai, Takashi; Obata-Ninomiya, Kazushige; Furushima-Shimogawara, Rieko; Kwansa-Bentum, Bethel; Akao, Nobuaki; Bosompem, Kwabena M; Boakye, Daniel A; Wilson, Michael D; Karasuyama, Hajime; Ohta, Nobuo

    2013-12-01

    Granuloma formation around parasite eggs during schistosomal infection is considered to be controlled by Th2 cytokines. However, it is still controversial which cell populations are responsible for the host Th2 cytokine-dependent granuloma formation. Basophils have recently attracted attention because of their ability to produce large amounts of IL-4. Therefore, we investigated whether basophils play an essential role in the induction of granuloma formation induced by Schistosoma mansoni eggs. Together with our previous observation that basophil numbers increased markedly in the spleen at 7 weeks postinfection, immunohistochemical staining using anti-mMCP8 monoclonal antibody (mAb) showed basophil infiltration in the granulomatous lesions formed around parasite eggs. To examine the roles of basophils more directly, we treated mice with anti-CD200R3 mAb to deplete basophils. Depletion of basophils resulted in a reduction of basophil number with concomitant downregulation of egg granuloma formation at 7 weeks postinfection. Moreover, we observed a significant reduction in the size of egg granulomas formed in basophil-depleted mice in the pulmonary granuloma model. Taken together, these findings indicated that basophils are essential for S. mansoni egg-induced granuloma formation, and this may serve as a novel therapeutic target in ameliorating the pathology of schistosomiasis. © 2013.

  7. Serological screening of the Schistosoma mansoni adult worm proteome.

    Directory of Open Access Journals (Sweden)

    Fernanda Ludolf

    2014-03-01

    Full Text Available BACKGROUND: New interventions tools are a priority for schistosomiasis control and elimination, as the disease is still highly prevalent. The identification of proteins associated with active infection and protective immune response may constitute the basis for the development of a successful vaccine and could also indicate new diagnostic candidates. In this context, post-genomic technologies have been progressing, resulting in a more rational discovery of new biomarkers of resistance and antigens for diagnosis. METHODOLOGY/PRINCIPAL FINDINGS: Two-dimensional electrophoresed Schistosoma mansoni adult worm protein extracts were probed with pooled sera of infected and non-infected (naturally resistant individuals from a S. mansoni endemic area. A total of 47 different immunoreactive proteins were identified by mass spectrometry. Although the different pooled sera shared most of the immunoreactive protein spots, nine protein spots reacted exclusively with the serum pool of infected individuals, which correspond to annexin, major egg antigen, troponin T, filamin, disulphide-isomerase ER-60 precursor, actin and reticulocalbin. One protein spot, corresponding to eukaryotic translation elongation factor, reacted exclusively with the pooled sera of non-infected individuals living in the endemic area. Western blotting of two selected recombinant proteins, major egg antigen and hemoglobinase, showed a similar recognition pattern of that of the native protein. CONCLUDING/SIGNIFICANCE: Using a serological proteome analysis, a group of antigens related to the different infection status of the endemic area residents was identified and may be related to susceptibility or resistance to infection.

  8. Natural infection of wild rodents by Schistosoma mansoni parasitological aspects

    Directory of Open Access Journals (Sweden)

    Rosângela Rodrigues e Silva

    1992-01-01

    Full Text Available The evaluation of the role of rodents as natural hosts of Schistosoma mansoni was studied at the Pamparrão Valley, Sumidouro, RJ, with monthly captures and examination of the animals. Twenty-three Nectomys squamipes and 9 Akodom arviculoides with a shistosomal infection rate of 56.5% and 22.2% respectively eliminated a great majority of viable eggs. With a strain isolated from one of the naturally infected N. squamipes, we infected 75% of simpatric Biomphalaria glabrata and 100% of albino Mus musculus mice. The adult worms, isolated from N. squamipes after perfusion were located mainly in the liver (91.5% and the mesenteric veins (8.5%. The male/female proportion was 2:1. The eggs were distributed on small intestine segments (proximal, medial and distal portions and the large intestine without any significant differences in egg concentration of these segments. In A. arviculoides, the few eggs eliminated by the stools were viable and there was litlle egg retention on intestinal segments. Considering the ease to complete S. mansoni biological cycle in the Nectomys/Biomphalaria/Nectomys system under laboratory conditions, probably the same is likely to occur in natural conditions. In support to this hypotesis there are also the facts that human mansonic shistosomiasis has a very low prevalence in Sumidouro and endemicity among the rodents has not changed even after repetead treatments of the local patients. Based on our experiments, we conclude that N. squamipes has become a natural host of S. mansoni and possibly may participate in keeping the cycle of schistosomiasis transmission at Pamparrão Valley.

  9. Esquistossomose mansônica: II - evolução dos níveis de proteínas séricas e do perfil eletroforético por técnicas de imunoeletroforese quantitativa Schistosomiasis mansoni: II - evolution of the levels of serum proteins and of their electrophoretic pattern as traced by quantitative immunoelectrophoresis

    Directory of Open Access Journals (Sweden)

    Ajax Mercês Atta

    1981-04-01

    Full Text Available Camundongos Swiss foram infectados com 100 cercárias da linhagem mineira (BH do Schistosoma mansoni e sacrificados semanalmente no período de 8 semanas de infecção. Os níveis de proteínas séricas totais destes animais não diferiram dos apresentados pelos animais controles. Os níveis de albumina sérica determinados por "Rocket immunoelectrophoresis" acharam-se diminuídos nas 5.ª, 6.ª e 7.ª semanas de infecção. O perfil obtido por imunoeletroforese cruzada revelou alterações em componentes séricos com mobilidade nas regiões de gama, beta e em menor grau de alfa-globulinas, após a oviposição do parasito.Swiss mice were infected with 100 cercariae of the Belo Horizonte strain of Schistosoma mansoni and were sacrificed weekly during eight weeks following of infection. The levels of serum protein totals in these animals did not differ from those presented by the control animals. However, serum albumin levels that were determined by rocket immunoelectrophoresis were lower during the 5th, 6th, and 7th weeks of infection. The pattern determined by crosed immunoelectrophoresis revealed alterations in serum components with mobility in the gamma and beta regions and, to a lesser degree, alpha-globulins, after oviposition by the parasite.

  10. Combination of the two schistosomal antigens Sm14 and Sm29 elicits significant protection against experimental Schistosoma mansoni infection.

    Science.gov (United States)

    Ewaisha, Radwa E; Bahey-El-Din, Mohammed; Mossallam, Shereen F; Amer, Eglal I; Aboushleib, Hamida M; Khalil, Amal M

    2014-10-01

    Schistosomiasis continues to be a serious helminthic disease that is widespread in many regions in the world. Disease management relies mainly on early treatment with praziquantel, nevertheless, re-infection rates can still be high. An effective vaccine against Schistosoma mansoni is still lacking; a situation which hinders the efforts to eradicate the disease worldwide. Most investigators test S. mansoni antigens individually, rather than in combination, in their vaccine trials. A single-antigen vaccine is likely to elicit less protection against schistosomiasis than a multi-antigen vaccine. In the current study, we have selected two promising S. mansoni antigens, Sm14 and Sm29, and investigated their combination as a potential vaccine. Recombinant Sm14 and a truncated form of Sm29, designated TrSm29, were successfully expressed in Escherichiacoli. The two antigens were purified using affinity chromatography and administered to Swiss albino mice individually and in combination. Significant protection against S. mansoni infection was observed in mice immunized with the Sm14/TrSm29 combination in the presence/absence of the immunoadjuvant poly (I:C). The poly (I:C)-adjuvanted combination resulted in 40.3%, 68.2%, and 57.9% reduction in adult worm burden, liver egg burden and intestinal eggs, respectively. Granuloma size and count were also reduced besides improvement of the histopathological picture of livers of immunized mice. This study demonstrates the importance of using multi-antigen vaccines as an effective and simple approach to fulfill enhanced protection against schistosomiasis. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. The Causal Role of IL-4 and IL-13 in Schistosoma mansoni Pulmonary Hypertension.

    Science.gov (United States)

    Kumar, Rahul; Mickael, Claudia; Chabon, Jacob; Gebreab, Liya; Rutebemberwa, Alleluiah; Garcia, Alexandra Rodriguez; Koyanagi, Daniel E; Sanders, Linda; Gandjeva, Aneta; Kearns, Mark T; Barthel, Lea; Janssen, William J; Mauad, Thais; Bandeira, Angela; Schmidt, Eric; Tuder, Rubin M; Graham, Brian B

    2015-10-15

    The etiology of schistosomiasis-associated pulmonary arterial hypertension (PAH), a major cause of PAH worldwide, is poorly understood. Schistosoma mansoni exposure results in prototypical type-2 inflammation. Furthermore, transforming growth factor (TGF)-β signaling is required for experimental pulmonary hypertension (PH) caused by Schistosoma exposure. We hypothesized type-2 inflammation driven by IL-4 and IL-13 is necessary for Schistosoma-induced TGF-β-dependent vascular remodeling. Wild-type, IL-4(-/-), IL-13(-/-), and IL-4(-/-)IL-13(-/-) mice (C57BL6/J background) were intraperitoneally sensitized and intravenously challenged with S. mansoni eggs to induce experimental PH. Right ventricular catheterization was then performed, followed by quantitative analysis of the lung tissue. Lung tissue from patients with schistosomiasis-associated and connective tissue disease-associated PAH was also systematically analyzed. Mice with experimental Schistosoma-induced PH had evidence of increased IL-4 and IL-13 signaling. IL-4(-/-)IL-13(-/-) mice, but not single knockout IL-4(-/-) or IL-13(-/-) mice, were protected from Schistosoma-induced PH, with decreased right ventricular pressures, pulmonary vascular remodeling, and right ventricular hypertrophy. IL-4(-/-)IL-13(-/-) mice had less pulmonary vascular phospho-signal transducer and activator of transcription 6 (STAT6) and phospho-Smad2/3 activity, potentially caused by decreased TGF-β activation by macrophages. In vivo treatment with a STAT6 inhibitor and IL-4(-/-)IL-13(-/-) bone marrow transplantation also protected against Schistosoma-PH. Lung tissue from patients with schistosomiasis-associated and connective tissue disease-associated PAH had evidence of type-2 inflammation. Combined IL-4 and IL-13 deficiency is required for protection against TGF-β-induced pulmonary vascular disease after Schistosoma exposure, and targeted inhibition of this pathway is a potential novel therapeutic approach for patients with

  12. Schistosomiasis and intestinal parasites in rural villages in southwest Nigeria: an indication for expanded programme on drug distribution and integrated control programme in Nigeria.

    Science.gov (United States)

    Adewunmi, C O; Gebremedhin, G; Becker, W; Olurunmola, F O; Dörfler, G; Adewunmi, T A

    1993-09-01

    A cross sectional survey of schistosomiasis, intestinal parasite infections and pattern of schistosomiasis transmission was undertaken in four rural villages around the Erinle dam, Nigeria. The prevalence of Schistosoma haematobium ranged from 10% to 60%. 30% of infected school children excreted over 50 eggs/10 ml urine and high rates of haematuria, proteinuria, leucocyturia and nitrites in urine were observed in infected children and the villagers. Prevalence of infection with S. mansoni ranged from 11.4% to 36.8%. Intensity of infection based on geometric mean eggs/gram of faeces ranged between 100 and 545.7 eggs/g. Malacological surveys showed that Biomphalaria pfeifferi was the predominant potential snail hosts recovered at all the contact sites. Higher infections with schistosome parasites were also recorded for B. pfeifferi than Bulinus globosus. The pattern of transmission of schistosomiasis by the snails is consistent and makes incorporation of community-based focal application of a molluscicide such as Tetrapleura tetraptera in integrated control of schistosomiasis feasible in the area. Prevalence and intensity with Ascaris lumbricoides was high. The highest prevalence was 68.9% while the highest intensity of infection was 2,440.9 eggs/gram of faeces. Multiple infections occured with various combinations of Ascaris lumbricoides, hookworm, S. haematobium, Fasciola gigantica, S. mansoni, and Entamoeba histolytica (as double, triple or quadruple infections). The results suggest an integrated approach to the control of schistosomiasis and intestinal parasites in this part of the country.

  13. Schistosome syntenin partially protects vaccinated mice against Schistosoma mansoni infection.

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    Barbara C Figueiredo

    2014-08-01

    Full Text Available Schistosomiasis is a neglected tropical disease caused by several species of trematode of the genus Schistosoma. The disease affects more than 200 million people in the world and causes up to 280,000 deaths per year, besides having high morbidity due to chronic illness that damages internal organs. Current schistosomiasis control strategies are mainly based on chemotherapy, but many researchers believe that the best long-term strategy to control disease is a combination of drug treatment and immunization with an anti-schistosome vaccine. Among the most promising molecules as vaccine candidates are the proteins present in the tegument and digestive tract of the parasite.In this study, we describe for the first time Schistosoma mansoni syntenin (SmSynt and we evaluate its potential as a recombinant vaccine. We demonstrate by real-time PCR that syntenin is mainly expressed in intravascular life stages (schistosomula and adult worms of the parasite life cycle and, by confocal microscopy, we localize it in digestive epithelia in adult worms and schistosomula. Administration of siRNAs targeting SmSynt leads to the knock-down of syntenin gene and protein levels, but this has no demonstrable impact on parasite morphology or viability, suggesting that high SmSynt gene expression is not essential for the parasites in vitro. Mice immunization with rSmSynt, formulated with Freund's adjuvant, induces a Th1-type response, as suggested by the production of IFN-γ and TNF-α by rSmSynt-stimulated cultured splenocytes. The protective effect conferred by vaccination with rSmSynt was demonstrated by 30-37% reduction of worm burden, 38-43% reduction in the number, and 35-37% reduction in the area, of liver granulomas.Our report is the first characterization of syntenin in Schistosoma mansoni and our data suggest that this protein is a potential candidate for the development of a multi-antigen vaccine to control schistosomiasis.

  14. Detection of Schistosoma mansoni and Schistosoma haematobium by Real-Time PCR with High Resolution Melting Analysis

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    Hany Sady

    2015-07-01

    Full Text Available The present study describes a real-time PCR approach with high resolution melting-curve (HRM assay developed for the detection and differentiation of Schistosoma mansoni and S. haematobium in fecal and urine samples collected from rural Yemen. The samples were screened by microscopy and PCR for the Schistosoma species infection. A pair of degenerate primers were designed targeting partial regions in the cytochrome oxidase subunit I (cox1 gene of S. mansoni and S. haematobium using real-time PCR-HRM assay. The overall prevalence of schistosomiasis was 31.8%; 23.8% of the participants were infected with S. haematobium and 9.3% were infected with S. mansoni. With regards to the intensity of infections, 22.1% and 77.9% of S. haematobium infections were of heavy and light intensities, respectively. Likewise, 8.1%, 40.5% and 51.4% of S. mansoni infections were of heavy, moderate and light intensities, respectively. The melting points were distinctive for S. mansoni and S. haematobium, categorized by peaks of 76.49 ± 0.25 °C and 75.43 ± 0.26 °C, respectively. HRM analysis showed high detection capability through the amplification of Schistosoma DNA with as low as 0.0001 ng/µL. Significant negative correlations were reported between the real-time PCR-HRM cycle threshold (Ct values and microscopic egg counts for both S. mansoni in stool and S. haematobium in urine (p < 0.01. In conclusion, this closed-tube HRM protocol provides a potentially powerful screening molecular tool for the detection of S. mansoni and S. haematobium. It is a simple, rapid, accurate, and cost-effective method. Hence, this method is a good alternative approach to probe-based PCR assays.

  15. Detection of Schistosoma mansoni and Schistosoma haematobium by Real-Time PCR with High Resolution Melting Analysis.

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    Sady, Hany; Al-Mekhlafi, Hesham M; Ngui, Romano; Atroosh, Wahib M; Al-Delaimy, Ahmed K; Nasr, Nabil A; Dawaki, Salwa; Abdulsalam, Awatif M; Ithoi, Init; Lim, Yvonne A L; Chua, Kek Heng; Surin, Johari

    2015-07-16

    The present study describes a real-time PCR approach with high resolution melting-curve (HRM) assay developed for the detection and differentiation of Schistosoma mansoni and S. haematobium in fecal and urine samples collected from rural Yemen. The samples were screened by microscopy and PCR for the Schistosoma species infection. A pair of degenerate primers were designed targeting partial regions in the cytochrome oxidase subunit I (cox1) gene of S. mansoni and S. haematobium using real-time PCR-HRM assay. The overall prevalence of schistosomiasis was 31.8%; 23.8% of the participants were infected with S. haematobium and 9.3% were infected with S. mansoni. With regards to the intensity of infections, 22.1% and 77.9% of S. haematobium infections were of heavy and light intensities, respectively. Likewise, 8.1%, 40.5% and 51.4% of S. mansoni infections were of heavy, moderate and light intensities, respectively. The melting points were distinctive for S. mansoni and S. haematobium, categorized by peaks of 76.49 ± 0.25 °C and 75.43 ± 0.26 °C, respectively. HRM analysis showed high detection capability through the amplification of Schistosoma DNA with as low as 0.0001 ng/µL. Significant negative correlations were reported between the real-time PCR-HRM cycle threshold (Ct) values and microscopic egg counts for both S. mansoni in stool and S. haematobium in urine (p < 0.01). In conclusion, this closed-tube HRM protocol provides a potentially powerful screening molecular tool for the detection of S. mansoni and S. haematobium. It is a simple, rapid, accurate, and cost-effective method. Hence, this method is a good alternative approach to probe-based PCR assays.

  16. Treatment and education reduce the severity of schistosomiasis periportal fibrosis

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    Paula Carolina Valenca Silva

    2013-07-01

    Full Text Available Introduction This study evaluates the factors associated with the development of severe periportal fibrosis in patients with Schistosoma mansoni. Methods A cross-sectional study was conducted from April to December 2012 involving 178 patients infected with S. mansoni who were treated in the Hospital das Clínicas of Pernambuco, Brazil. Information regarding risk factors was obtained using a questionnaire. Based on the patients' epidemiological history, clinical examination, and upper abdomen ultrasound evaluation, patients were divided into 2 groups: 137 with evidence of severe periportal fibrosis and 41 patients without fibrosis or with mild or moderate periportal fibrosis. Univariate and multivariate analyses were conducted using EpiInfo software version 3.5.5. Results Illiterate individuals (30.1% and patients who had more frequent contact with contaminated water in towns in the Zona da Mata of Pernambuco (33.2% were at greater risk for severe periportal fibrosis. Based on multivariate analysis, it was determined that an education level of up to 11 years of study and specific prior treatment for schistosomiasis were preventive factors for severe periportal fibrosis. Conclusions The prevailing sites of the severe forms of periportal fibrosis are still within the Zona da Mata of Pernambuco, although there has been an expansion to urban areas and the state coast. Specific treatment and an increased level of education were identified as protective factors, indicating the need for implementing social, sanitary, and health education interventions aimed at schistosomiasis to combat the risk factors for this major public health problem.

  17. Absence of linkage between MHC and a gene involved in susceptibility to human schistosomiasis

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    Chiarella J.M.

    1998-01-01

    Full Text Available Six hundred million people are at risk of infection by Schistosoma mansoni. MHC haplotypes have been reported to segregate with susceptibility to schistosomiasis in murine models. In humans, a major gene related to susceptibility/resistance to infection by S. mansoni (SM1 and displaying the mean fecal egg count as phenotype was detected by segregation analysis. This gene displayed a codominant mode of inheritance with an estimated frequency of 0.20-0.25 for the deleterious allele and accounted for more than 50% of the variance of infection levels. To determine if the SM1 gene segregates with the human MHC chromosomal region, we performed a linkage study by the lod score method. We typed for HLA-A, B, C, DR and DQ antigens in 11 informative families from an endemic area for schistosomiasis in Bahia, Brazil, by the microlymphocytotoxicity technique. HLA-DR typing by the polymerase chain reaction with sequence-specific primers (PCR-SSP and HLA-DQ were confirmed by PCR-sequence-specific oligonucleotide probes (PCR-SSOP. The lod scores for the different q values obtained clearly indicate that there is no physical linkage between HLA and SM1 genes. Thus, susceptibility or resistance to schistosomiasis, as defined by mean fecal egg count, is not primarily dependent on the host's HLA profile. However, if the HLA molecule plays an important role in specific immune responses to S. mansoni, this may involve the development of the different clinical aspects of the disease such as granuloma formation and development of hepatosplenomegaly.

  18. Eukaryotic Protein Kinases (ePKs of the Helminth Parasite Schistosoma mansoni

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    Zerlotini Adhemar

    2011-05-01

    Full Text Available Abstract Background Schistosomiasis remains an important parasitic disease and a major economic problem in many countries. The Schistosoma mansoni genome and predicted proteome sequences were recently published providing the opportunity to identify new drug candidates. Eukaryotic protein kinases (ePKs play a central role in mediating signal transduction through complex networks and are considered druggable targets from the medical and chemical viewpoints. Our work aimed at analyzing the S. mansoni predicted proteome in order to identify and classify all ePKs of this parasite through combined computational approaches. Functional annotation was performed mainly to yield insights into the parasite signaling processes relevant to its complex lifestyle and to select some ePKs as potential drug targets. Results We have identified 252 ePKs, which corresponds to 1.9% of the S. mansoni predicted proteome, through sequence similarity searches using HMMs (Hidden Markov Models. Amino acid sequences corresponding to the conserved catalytic domain of ePKs were aligned by MAFFT and further used in distance-based phylogenetic analysis as implemented in PHYLIP. Our analysis also included the ePK homologs from six other eukaryotes. The results show that S. mansoni has proteins in all ePK groups. Most of them are clearly clustered with known ePKs in other eukaryotes according to the phylogenetic analysis. None of the ePKs are exclusively found in S. mansoni or belong to an expanded family in this parasite. Only 16 S. mansoni ePKs were experimentally studied, 12 proteins are predicted to be catalytically inactive and approximately 2% of the parasite ePKs remain unclassified. Some proteins were mentioned as good target for drug development since they have a predicted essential function for the parasite. Conclusions Our approach has improved the functional annotation of 40% of S. mansoni ePKs through combined similarity and phylogenetic-based approaches. As we

  19. First report of schistosomiasis on Serrambi beach, Ipojuca, State of Pernambuco

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    Verônica Santos Barbosa

    2015-12-01

    Full Text Available Abstract: INTRODUCTION : The expansion of schistosomiasis to previously unaffected areas is being monitored by identifying new cases and georeferencing outbreaks of vector snails. METHODS : In 2014, the Laboratório de Esquistossomose began an epidemiological survey in Serrambi and registered 2,574 people living there. RESULTS : Of these subjects, 1,414 (54.9% underwent feces examination and 63 (4.5% were diagnosed with Schistosoma mansoni infection. At this locality, seven breeding sites each were identified for Biomphalaria straminea and Biomphalaria glabrata. At two sites, B. glabrata were shedding cercariae. CONCLUSIONS : Implementing preventive measures is necessary to avoid the establishment of schistosomiasis in yet another tourist locality, Pernambuco.

  20. Schistosomiasis risk mapping in the state of Minas Gerais, Brazil, using a decision tree approach, remote sensing data and sociological indicators

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    Flávia T Martins-Bedê

    2010-07-01

    Full Text Available Schistosomiasis mansoni is not just a physical disease, but is related to social and behavioural factors as well. Snails of the Biomphalaria genus are an intermediate host for Schistosoma mansoni and infect humans through water. The objective of this study is to classify the risk of schistosomiasis in the state of Minas Gerais (MG. We focus on socioeconomic and demographic features, basic sanitation features, the presence of accumulated water bodies, dense vegetation in the summer and winter seasons and related terrain characteristics. We draw on the decision tree approach to infection risk modelling and mapping. The model robustness was properly verified. The main variables that were selected by the procedure included the terrain's water accumulation capacity, temperature extremes and the Human Development Index. In addition, the model was used to generate two maps, one that included risk classification for the entire of MG and another that included classification errors. The resulting map was 62.9% accurate.

  1. Perceptions about interventions to control schistosomiasis among the Lake Victoria island communities of Koome, Uganda.

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    Richard E Sanya

    2017-10-01

    Full Text Available Praziquantel-based mass treatment is the main approach to controlling schistosomiasis mansoni in endemic areas. Interventions such as provision and use of safe water, minimising contact with infested water, disposal of stool in latrines and snail control provide key avenues to break the transmission cycle and can sustain the benefits of mass treatment in the long term. Efforts are also being made to develop a schistosomiasis vaccine which, if effective, might reduce the incidence of re-infection after treatment. However, any interventions deployed need to be acceptable to, and sustainable by, the target communities.In this qualitative study, we investigated the perceptions of six Lake Victoria island communities of Koome, Uganda, about interventions to control Schistosoma mansoni infection and their willingness to participate in Schistosoma vaccine trials. Thirty-two in-depth interviews, 12 key informant interviews and 10 focus group discussions were conducted. Data were analysed using a thematic content approach.Intestinal schistosomiasis was not regarded as a serious health problem because a mass treatment programme is in place. However, the communities lack safe water sources and latrines. Mass treatment with praziquantel, safe water supplies and use of toilets were deemed the most acceptable interventions by the participants. The communities are willing to participate in Schistosoma vaccine trials.Knowledge of a community's perception about interventions to control schistosomiasis can be valuable to policy makers and programme implementers intending to set up interventions co-managed by the community members. In this study, the views of the Lake Victoria island communities of Koome are presented. This study also provides data to guide further work on alternative interventions such as Schistosoma vaccine trials in these communities.

  2. Predicting the effects of climate change on Schistosoma mansoni transmission in eastern Africa.

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    McCreesh, Nicky; Nikulin, Grigory; Booth, Mark

    2015-01-06

    Survival and fitness attributes of free-living and sporocyst schistosome life-stages and their intermediate host snails are sensitive to water temperature. Climate change may alter the geographical distribution of schistosomiasis by affecting the suitability of freshwater bodies for hosting parasite and snail populations. We have developed an agent-based model of the temperature-sensitive stages of the Schistosoma mansoni and intermediate host snail lifecycles. The model was run using low, moderate and high warming climate projections over eastern Africa. For each climate projection, eight model scenarios were used to determine the sensitivity of predictions to different relationships between air and water temperature, and different snail mortality rates. Maps were produced showing predicted changes in risk as a result of increasing temperatures over the next 20 and 50 years. Baseline model output compared to prevalence data indicates suitable temperatures are necessary but not sufficient for both S. mansoni transmission and high infection prevalences. All else being equal, infection risk may increase by up to 20% over most of eastern Africa over the next 20 and 50 years. Increases may be higher in Rwanda, Burundi, south-west Kenya and eastern Zambia, and S. mansoni may become newly endemic in some areas. Results for 20-year projections are robust to changes in simulated intermediate host snail habitat conditions. There is greater uncertainty about the effects of different habitats on changes in risk in 50 years' time. Temperatures are likely to become suitable for increased S. mansoni transmission over much of eastern Africa. This may reduce the impact of control and elimination programmes. S. mansoni may also spread to new areas outside existing control programmes. We call for increased surveillance in areas defined as potentially suitable for emergent transmission.

  3. Low transmission areas of schistosomiasis in Venezuela: consequences on the diagnosis, treatment, and control

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    Belkisyolé Alarcón de Noya

    2006-10-01

    Full Text Available Schistosomiasis low transmission areas as Venezuela, can be defined as those where the vector exists, the prevalence of active cases is under 25%, individuals with mild intensity of infection predominate and are mostly asymptomatic. These areas are the consequence of effective control programs, however, "silent" epidemiological places are difficult to trace, avoiding the opportune diagnosis and treatment of infected persons. Clinic and abdominal ultrasound have not shown to discriminate infected from uninfected persons in areas where besides Schistosoma mansoni, intestinal parasites are the rule. Under these conditions, serology remains as a very valuable diagnostic tool, since it gives a closer approximation to the true prevalence. In this sense, circumoval precipitin test, ELISA-SEA with sodium metaperiodate, and alkaline phosphatase immunoassay joined to coprology allow the identification of the "schistosomiasis cases". In relation to public health, schistosomiasis has been underestimated by the sanitary authorities and the investment on its control is being transferred to other diseases of major social and political relevance neglecting sanitary efforts and allowing growth of snail population. Some strategies of diagnosis and control should be done before schistosomiasis reemergence occurs in low transmission areas.

  4. Improvement of a tissue maceration technique for the determination of placental involvement in schistosomiasis.

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    Holtfreter, Martha Charlotte; Neubauer, Heinrich; Groten, Tanja; El-Adawy, Hosny; Pastuschek, Jana; Richter, Joachim; Häussinger, Dieter; Pletz, Mathias Wilhelm; Schleenvoigt, Benjamin Thomas

    2017-04-01

    Schistosomiasis in pregnancy may cause low birth weight, prematurity and stillbirth of the offspring. The placenta of pregnant women might be involved when schistosome ova are trapped in placental tissue. Standard histopathological methods only allow the examination of a limited amount of placental tissue and are therefore not sufficiently sensitive. Thus, placental schistosomiasis remains underdiagnosed and its role in contributing to schistosomiasis-associated pregnancy outcomes remains unclear. Here we investigated an advanced maceration method in order to recover a maximum number of schistosome ova from the placenta. We examined the effect of different potassium hydroxide (KOH) concentrations and different tissue fixatives with respect to maceration success and egg morphology. Placental tissue was kept either in 0.9% saline, 5% formalin or 70% ethanol and was macerated together with Schistosoma mansoni infested mouse livers and KOH 4% or 10%, respectively. We found that placenta maceration using 4% KOH at 37°C for 24 h was the most effective method: placental tissue was completely digested, egg morphology was well preserved and alkaline concentration was the lowest. Ethanol proved to be the best fixative for this method. Here we propose an improved maceration technique in terms of sensitivity, safety and required skills, which may enable its wider use also in endemic areas. This technique may contribute to clarifying the role of placental involvement in pregnant women with schistosomiasis.

  5. Water-contact patterns and risk factors for Schistosoma mansoni infection in a rural village of Northeast Brazil

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    SILVA Antônio Augusto Moura da

    1997-01-01

    Full Text Available Schistosomiasis mansoni in the Serrano village, municipality of Cururupu, state of Maranhão, Brazil, is a widely spread disease. The PECE (Program for the Control of Schistosomiasis, undertaken since 1979 has reduced the prevalence of S. mansoni infection and the hepatosplenic form of the disease. Nevertheless piped water is available in 84% of the households, prevalence remains above 20%. In order to identify other risk factors responsible for the persistence of high prevalence levels, a cross-sectional survey was carried out in a systematic sample of 294 people of varying ages. Socioeconomic, environmental and demographic variables, and water contact patterns were investigated. Fecal samples were collected and analyzed by the Kato-Katz technique. Prevalence of S. mansoni infection was 24.1%, higher among males (35.5% and between 10-19 years of age (36.6%. The risk factors identified in the univariable analysis were water contacts for vegetable extraction (Risk Ratio - RR = 2.92, crossing streams (RR = 2.55, bathing (RR = 2.35, fishing (RR = 2.19, hunting (RR = 2.17, cattle breeding (RR = 2.04, manioc culture (RR = 1.90 and leisure (RR = 1.56. After controlling for confounding variables by proportional hazards model the risks remained higher for males, vegetable extraction, bathing in rivers and water contact in rivers or in periodically inundated parts of riverine woodland (swamplands

  6. Optimization of the Helmintex method for schistosomiasis diagnosis.

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    Favero, Vivian; Frasca Candido, Renata Russo; De Marco Verissimo, Carolina; Jones, Malcolm K; St Pierre, Timothy G; Lindholz, Catieli Gobetti; Da Silva, Vinicius Duval; Morassutti, Alessandra Loureiro; Graeff-Teixeira, Carlos

    2017-06-01

    A diagnostic test that is reliable, sensitive, and applicable in the field is extremely important in epidemiological surveys, during medical treatment for schistosomiasis, and for the control and elimination of schistosomiasis. The Helmintex (HTX) method is based on the use of magnetic beads to trap eggs in a magnetic field. This technique is highly sensitive, but the screening of fecal samples consumes lots of time, thus delaying the results, especially in field studies. The objective of this work was to determine the effects of incorporation of the detergent Tween-20 into the method in an attempt to decrease the final pellet volume produced by the HTX method as well as the use of ninhydrin to stain the Schistosoma mansoni eggs. We showed that these modifications reduced the final volume of the fecal sediment produced in the last step of the HTX method by up to 69% and decreased the screening time to an average of 10.1 min per sample. The use of Tween 20 and ninhydrin led to a high percentage of egg recovery (27.2%). The data obtained herein demonstrate that the addition of detergent and the use of ninhydrin to the HTX process can optimize the screening step and also improve egg recovery, thus justifying the insertion of these steps into the HTX method. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Comparison of purified 12 kDa and recombinant 15 kDa Fasciola hepatica antigens related to a Schistosoma mansoni fatty acid binding protein

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    George V. Hillyer

    1995-04-01

    Full Text Available Vaccines in schistosomiasis using homologous antigens have been studied extensively in experimentally infected mammalian hosts. Vaccines using heterologous antigens have received comparatively less attention. This review summarizes recent work on a heterologous 12 kDa Fasciola hepatica antigenic polypeptide which cross reacts with Schistosoma mansoni. A cDNA has been cloned and sequenced, and the predicted amino acid sequence of the recombinant protein has been shown to have significant (44 identity with a 14 kDa S. mansoni fatty acid binding protein. Thus in the parasitic trematodes fatty acid binding proteins may be potential vaccine candidates. The F. hepatica recombinant protein has been overexpressed and purified and denoted rFh15. Preliminary rFh15 migrates more slowly (i.e. may be slightly larger than nFh12 on SDS-PAGE and has a predicted pI of 6.01 vs. observed pI of 5.45. Mice infected with F. hepatica develop antibodies to nFh12 by 2 weeks of infection vs. 6 weeks of infection to rFh15; on the other hand, mice with schistosomiasis mansoni develop antibodies to both nFh12 and rFh15 by 6 weeks of infection. Both the F. hepatica and S. mansoni cross-reactive antigens may be cross-protective antigens with the protection inducing capability against both species.

  8. Molluscicides in schistosomiasis control.

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    McCullough, F S; Gayral, P; Duncan, J; Christie, J D

    1980-01-01

    Although mollusciciding can be a cost-effective method of controlling schistosomiasis transmission, only one organic molluscicide, niclosamide, is now being produced commercially, and only a few compounds are at present being tested in the laboratory. In future, improved cost-effective use of molluscicides will require more precise knowledge of schistosomiasis transmission patterns in each endemic area and improved application techniques. In snail control studies using controlled-release formulations only the organotins, especially tributyltin oxide (TBTO), have given satisfactory long-term results. However, large-scale field trials of organotin formulations have not been implemented and their use cannot be recommended as their chronic toxicity in mammals has not yet been determined. The development of molluscicides of indigenous plant origin deserves support. Endod, derived from the berries of the climbing plant Phytolacca dodecandra, is the most extensively tested plant molluscicide, but data on its chronic toxicity to non-target organisms are lacking. The mode of action of molluscicides has not been extensively studied, though knowledge of the properties required of molluscicidal molecules has contributed to the discovery and development of niclosamide and nicotinanilide. In general, molluscicides probably cause stress on the water balance system, which in gastropods in thought to be under neurosecretory control.

  9. MONITORING POSITIVITY FOR Schistosoma mansoni IN RODENTS Holochilus sp. NATURALLY INFECTED

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    Guilherme Silva Miranda

    2015-07-01

    Full Text Available The occurrence of non-human mammals such as schistosomiasis reservoir has always been an aggravating factor to be studied. Family cricetidae rodents like Nectomys sp, seem to have an important role in the potentiation of the spread of it. However, for Holochilus sp. (Rodentia: Cricetidae, found in Maranhão, studies with this function seem scarce. Thereby, we aimmed to analyze the infection rate of these animals for S. mansoni in São Bento – MA, endemic area for the parasite. These rodents were monitored during 12 months, by the Tomahawk traps for caught and triplicates of stool tests blades, made by Kato–Katz kit, for parasitogical exam. A total of 101 rodents were captured, of which 28.7% were naturally infected by S. mansoni (17.3% females and 82.7% males. This analysis showed that an average of 2.4 rodents was infected for one year, being possible to find positive animals in almost all the collects. Therefore, the rodent Holochilus sp. is a potential candidate in ensuring the maintenance of the schistosomiasis cycle in the region under study.

  10. In-silico screening of Schistosoma mansoni Sirtuin1 inhibitors for prioritization of drug candidates.

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    Singh, Raghvendra; Yadav, Birendra Singh; Singh, Swati; Pandey, Paras Nath; Mani, Ashutosh

    2016-01-01

    Schistosomiasis is a common, neglected parasitic disease caused by Schistosoma mansoni. Availability of two specific drug oxamniquine and praziquintel for treatment of the disease is a major concern. Recently NAD+ dependent lysine deacetylases have been identified as new drug targets in pathogens. Sirtuins are NAD+ dependent lysine deacetylases that are involved in a wide variety of vital cellular processes. Amongst them, members of sirtuin's class1 proteins are considered to be main target of the drugs. Sirtinol and Salermide are two known inhibitors of Schistosoma mansoni Class1sirtuin which is a protein with unknown 3-D structure. Here, we investigate molecular insights of interaction between modeled sirtuin1 structure and it's inhibitors, that were derivatives of Sirtinol and Salermide, to prioritize them for their binding affinities with target. A detailed examination of absorption, distribution, metabolism and toxicity of these inhibitors has also been included in the study. Finally we found two derivatives of Sirtinol to be most appropriate drug candidates for Schistosomiasis.

  11. A patologia da esquistossomose mansoni no coelho Pathology of Manson's shistosomiasis in rabits

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    Zilton A. Andrade

    1988-09-01

    Full Text Available Coelhos com infecções maciças (20.000 cercárias pelo Schistosoma mansoni desenvolvendo dentro de três a dez meses intensas e peculiares lesões no sistema porta intrahepático; estas consisten en endoflebite poliposa e endoflebite granulomatosa oclusiva, que evoluem para a cicatrização, com hialinização dos polipos endoteliais e com ectasia vascular, ou com trombose, organização e recanalização. Nos períodos tardios, estas lesões se acompanham de fibrose periportal, septal e de espessamento da trama reticular intra-parenquimal. Embora podendo ser bem intensas, tais lesões têm um caráter focal, pois se relacionam com grupos de vermes alojados em alguns segmentos da veia porta, não determinam hipertensão porta, nem têm semelhanças com as lesões da esquistossomose humana. Os granulomas periovulares quase não aparecem no fígado, mas se formam bem nos intestinos, especialmetne nos dois ou três primeiros meses após a infecção. A patologia da esquistossomose no coelho tem, portanto, aspectos peculiares, os quais merecem ser bem conhecidos, uma vez que este modelo pode se revelar de interesse para estudantes dos imunológicos e imunopatológicos.The pathology of Schistosomiasis mansoni in rabbits was studied with special consideration to worm burden and duration of infection. Heavy and prolonged infectious resulted in severe changes involving the intrahepatic portal vein branches, such as: polypoid endophlebitis, granulomatous endophlebitis and, later on, vascular occlusion and recanalization, vascular ectasia, fibrosis and hyalinization of the endothelial polyps. Living and dead adult worms, rather than the mature eggs, were the main pathogenetic factors. For some time the lesions tend to be limited to the portal vein banches, not extending to the periportal tissues, but, after 8 to 10 months, variable degree of portal, septal and intra-parenchymal fibrosis can be formed. However, both vascular and fibrotic changes in the

  12. Experimental evidence and ecological perspectives for the adaptation of Schistosoma mansoni Sambon, 1907 (Digenea: Schistosomatidae to a wild host, the water-rat, Nectomys squamipes Brants, 1827 (Rodentia: Sigmodontinae

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    Paulo Sérgio D'Andrea

    2002-10-01

    Full Text Available Due to the semi aquatic habits and the overlap of the geographical distribution of the water-rat, Nectomys spp., with schistosomiasis endemic areas, these wild rodents are very likely to acquire Schistosoma mansoni infection in their daily activities. The role of the water-rat in the S. mansoni cycle would be substantiated if one could prove that these rodents acquire the parasite during their own activity time, a completely independent time schedule of human activities. To pursue this goal, we performed two field experiments in the municipality of Sumidouro, State of Rio de Janeiro, Brazil, a schistosomiasis endemic area where N. squamipes is found naturally infected. One experiment was devised as a series of observations of activity time of the water-rat. The other experiment was a test of the occurrence of late transmission of S. mansoni to the water-rat. The daily activity pattern showed that the water-rat is active chiefly just after sunset. At both diurnal and late exposition essays the water-rat sentinels got infected by S. mansoni. These findings clarify ecological and behavioral components necessary to the adaptation of S. mansoni to the water-rat as a non human definitive host and the existence of a transmission cycle involving this animals as a reservoir.

  13. Epidemiology of intestinal helminthiasis among school children with emphasis on Schistosoma mansoni infection in Wolaita zone, Southern Ethiopia

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    Bereket Alemayehu

    2017-06-01

    Full Text Available Abstract Background Intestinal helminth infections are major parasitic diseases causing public health problems in Ethiopia. Although the epidemiology of these infections are well documented in Ethiopia, new transmission foci for schistosomiasis are being reported in different parts of the country. The objective of this study was to assess the prevalence of Schistosoma mansoni and other intestinal helminth infections among school children and determine the endemicity of schistosomiasis in Wolaita Zone, southern Ethiopia. Methods Cross-sectional parasitological and malacological surveys were conducted by collecting stool samples for microscopic examination and snails for intermediate host identification. Stool samples were collected from 503 children and processed for microscopic examination using Kato-Katz and formalin-ether concentration methods. Snails collected from aquatic environments in the study area were identified to species level and Biomphalaria pfeifferi snails, the intermediate host of S. mansoni,, were individually exposed to artificial light in order to induce cercariae shedding. Cercariae shed from snails were used to infect laboratory-bred Swiss albino mice in order to identify the schistosome to species level. Results The overall prevalence of intestinal helminth infections was 72.2% among school children. S. mansoni infection prevalence was 58.6%. The prevalence and intensity of S. mansoni infections varied among schools and sex of children. Swimming was the only factor reported to be significantly associated with S. mansoni infection (AOR = 2.954, 95% CI:1.962-4.449. Other intestinal helminth species identified were hookworms (27.6%, Ascaris lumbricoides (8.7%, E. vermicularis (2.8%, Taenia species (2.6%, T. trichiura (1.2% and H. nana (0.6%. Only B. pfeifferi snails collected from streams shed schistosome cercariae and 792 adult S. mansoni worms were harvested from mice exposed to cercariae shed from B. pfeifferi on the 6th

  14. Epidemiology of intestinal helminthiasis among school children with emphasis on Schistosoma mansoni infection in Wolaita zone, Southern Ethiopia.

    Science.gov (United States)

    Alemayehu, Bereket; Tomass, Zewdneh; Wadilo, Fiseha; Leja, Dawit; Liang, Song; Erko, Berhanu

    2017-06-20

    Intestinal helminth infections are major parasitic diseases causing public health problems in Ethiopia. Although the epidemiology of these infections are well documented in Ethiopia, new transmission foci for schistosomiasis are being reported in different parts of the country. The objective of this study was to assess the prevalence of Schistosoma mansoni and other intestinal helminth infections among school children and determine the endemicity of schistosomiasis in Wolaita Zone, southern Ethiopia. Cross-sectional parasitological and malacological surveys were conducted by collecting stool samples for microscopic examination and snails for intermediate host identification. Stool samples were collected from 503 children and processed for microscopic examination using Kato-Katz and formalin-ether concentration methods. Snails collected from aquatic environments in the study area were identified to species level and Biomphalaria pfeifferi snails, the intermediate host of S. mansoni,, were individually exposed to artificial light in order to induce cercariae shedding. Cercariae shed from snails were used to infect laboratory-bred Swiss albino mice in order to identify the schistosome to species level. The overall prevalence of intestinal helminth infections was 72.2% among school children. S. mansoni infection prevalence was 58.6%. The prevalence and intensity of S. mansoni infections varied among schools and sex of children. Swimming was the only factor reported to be significantly associated with S. mansoni infection (AOR = 2.954, 95% CI:1.962-4.449). Other intestinal helminth species identified were hookworms (27.6%), Ascaris lumbricoides (8.7%), E. vermicularis (2.8%), Taenia species (2.6%), T. trichiura (1.2%) and H. nana (0.6%). Only B. pfeifferi snails collected from streams shed schistosome cercariae and 792 adult S. mansoni worms were harvested from mice exposed to cercariae shed from B. pfeifferi on the 6th week post-exposure. The present study found high

  15. Fagocitose e viabilidade monocitária de pacientes com esquistossomose mansônica na forma hepatoesplênica submetidos à esplenectomia e ao auto-implante esplênico Phagocytes rate and cellular viability of the monocytes in patients with hepatosplenic schistosomiasis mansoni who underwent splenectomy and auto-implantation of spleen tissue

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    Carlos Teixeira Brandt

    2006-10-01

    Full Text Available Esquistossomose mansônica persiste como problema médico-social no nordeste brasileiro. Em crianças, o tratamento cirúrgico inclui esplenectomia e auto-implante esplênico. Este procedimento reduz a septicemia pós-esplenectomia. O objetivo deste estudo foi analisar a taxa de fagocitose e viabilidade de fagócitos mononucleares em portadores de esquistossomose hepatoesplênica, submetidos à cirurgia, de 1991 a 2001. Dos 22 indivíduos analisados, 11 eram portadores de esquistossomose hepatoesplênica, submetidos à esplenectomia e auto-implante esplênico (Grupo estudo e 11 eram sadios (Grupo Controle. Os grupos tinham média de idades similar e procediam da mesma zona endêmica (Timbaúba-PE. Não se evidenciou diferença na taxa de fagocitose comparando-se o grupo controle (36,1%±4,9% e o grupo estudo (33,5%±5,7%, p=0,2773. Todavia, a viabilidade dos fagócitos após estímulo com lipopolissacarídio foi maior (94% no grupo controle, quando comparado ao grupo estudo (65%, pMansonic schistosomiasis remains a medical-social issue in Northeastern Brazil. In children, surgical treatment includes splenectomy and spleen autoimplantation. This procedure reduces post-splenectomy sepsis. The aim of this study was to analyze the phagocyte rate and the cellular viability of monocytes in patients with hepatosplenic schistosomiasis, who underwent splenectomy and spleen autoimplantation from 1991 to 2001. Of the 22 individuals analyzed, 11 were patients who underwent splenectomy and spleen autoimplantation (Study group and 11 were healthy individuals from the same region (Control group. Both groups presented similar mean age. No difference was found in the phagocyte rate between the control group (36.1%±4.9% and study group (33.5%±5.7%. However, phagocyte viability after stimulation with lipopolysaccharide was higher (94% in control group, when compared to the study group (65%, p<0.001. It is possible to hypothesize that monocytes from the study

  16. Detection of Schistosoma mansoni and Schistosoma haematobium by Real-Time PCR with High Resolution Melting Analysis

    Science.gov (United States)

    Sady, Hany; Al-Mekhlafi, Hesham M.; Ngui, Romano; Atroosh, Wahib M.; Al-Delaimy, Ahmed K.; Nasr, Nabil A.; Dawaki, Salwa; Abdulsalam, Awatif M.; Ithoi, Init; Lim, Yvonne A. L.; Chua, Kek Heng; Surin, Johari

    2015-01-01

    The present study describes a real-time PCR approach with high resolution melting-curve (HRM) assay developed for the detection and differentiation of Schistosoma mansoni and S. haematobium in fecal and urine samples collected from rural Yemen. The samples were screened by microscopy and PCR for the Schistosoma species infection. A pair of degenerate primers were designed targeting partial regions in the cytochrome oxidase subunit I (cox1) gene of S. mansoni and S. haematobium using real-time PCR-HRM assay. The overall prevalence of schistosomiasis was 31.8%; 23.8% of the participants were infected with S. haematobium and 9.3% were infected with S. mansoni. With regards to the intensity of infections, 22.1% and 77.9% of S. haematobium infections were of heavy and light intensities, respectively. Likewise, 8.1%, 40.5% and 51.4% of S. mansoni infections were of heavy, moderate and light intensities, respectively. The melting points were distinctive for S. mansoni and S. haematobium, categorized by peaks of 76.49 ± 0.25 °C and 75.43 ± 0.26 °C, respectively. HRM analysis showed high detection capability through the amplification of Schistosoma DNA with as low as 0.0001 ng/µL. Significant negative correlations were reported between the real-time PCR-HRM cycle threshold (Ct) values and microscopic egg counts for both S. mansoni in stool and S. haematobium in urine (p PCR assays. PMID:26193254

  17. Sintomatologia intestinal na fase crônica da esquistossomose mansoni

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    Eleonora L. Peixinho

    1986-03-01

    Full Text Available Com o objetivo de investigar os sintomas intestinais na fase crônica da esquistossomose mansoni, estudamos 102 indivíduos na faixa etária de nove a dezenove anos, dos 144previamente selecionados entre os moradores autóctones dos distritos de Lagoa Redonda e Menezes, portadores de Schistosoma mansoni. Todos foram submetidos a uma anamnese segmentar com a finalidade de detectara presença de cinco sintomas intestinais: dor abdominal, diarréia, muco e rajas de sangue nas fezes e enterorragia. Metade dos pacientes foi medicada com mebendazole e posteriormente com oxamniquine, constituindo-se no grupo caso, enquanto a outra metade, tratada apenas com mebendazole, constituiu-se no grupo controle. Os resultados mostram que a esquistossomose é provavelmente a responsável pelas queixas de muco e/ou rajas de sangue nas fezes, ocorrendo uma redução dessas queixas, estatisticamente significante, após a terapêutica específica.A total of 102 autochthonous patients from the districts of Lagoa Redonda and Menezes (Sapeaçu, Bahia, with ages rangingfrom nine to 19years, were evaluated for intestinal symptoms related to the chronic phase of Schistosomiasis mansoni, with emphasis on the following complaints: abdominal pain, diarrhea, mucus and blood in the stools. One half of the sample (case group was treated with mebendazole followed by oxamniquine; the otherhalf (control group received only mebendazole. The results showed that schistosomiasis is probably responsible for the appearance of mucus and/or blood in the stools, since a statistically significant reduction of such manifestations was achieved with specific treatment.

  18. Soil transmitted helminths and schistosoma mansoni infections among school children in zarima town, northwest Ethiopia

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    Birhan Wubet

    2011-07-01

    Full Text Available Abstract Background In Ethiopia, because of low quality drinking water supply and latrine coverage, helminths infections are the second most predominant causes of outpatient morbidity. Indeed, there is a scarcity of information on the prevalence of soil transmitted helminths and Schistosomiasis in Ethiopia, special in study area. Therefore, the aim of this study was to determine the prevalence and associated risk factors of soil transmitted helminths and intestinal Schistosomiasis. Methods Cross-sectional study was conducted among 319 school children of Zarima town from April 1 to May 25, 2009. A pre-tested structured questionnaire was used to collect socio-demographic data and possible risk factors exposure. Early morning stool samples were collected and a Kato Katz semi concentration technique was used to examine and count parasitic load by compound light microscope. Data entry and analysis was done using SPSS-15 version and p-value Results Out of 319 study subjects, 263 (82.4% of the study participants infected with one or more parasites. From soil transmitted helminths, Ascaris lumbricoides was the predominant isolate (22% followed by Hookworms (19% and Trichuris trichiura (2.5%. Schistosoma mansoni was also isolated in 37.9% of the study participants. Hookworm and S. mansoni infections showed statistically significant associations with shoe wearing and swimming habit of school children, respectively. Conclusion Prevalence of soil transmitted helminths (STH and S.mansoni was high and the diseases were still major health problem in the study area which alerts public health intervention as soon as possible.

  19. Combined spatial prediction of schistosomiasis and soil-transmitted helminthiasis in Sierra Leone: a tool for integrated disease control.

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    Mary H Hodges

    Full Text Available BACKGROUND: A national mapping of Schistosoma haematobium was conducted in Sierra Leone before the mass drug administration (MDA with praziquantel. Together with the separate mapping of S. mansoni and soil-transmitted helminths, the national control programme was able to plan the MDA strategies according to the World Health Organization guidelines for preventive chemotherapy for these diseases. METHODOLOGY/PRINCIPAL FINDINGS: A total of 52 sites/schools were selected according to prior knowledge of S. haematobium endemicity taking into account a good spatial coverage within each district, and a total of 2293 children aged 9-14 years were examined. Spatial analysis showed that S. haematobium is heterogeneously distributed in the country with significant spatial clustering in the central and eastern regions of the country, most prevalent in Bo (24.6% and 8.79 eggs/10 ml, Koinadugu (20.4% and 3.53 eggs/10 ml and Kono (25.3% and 7.91 eggs/10 ml districts. By combining this map with the previously reported maps on intestinal schistosomiasis using a simple probabilistic model, the combined schistosomiasis prevalence map highlights the presence of high-risk communities in an extensive area in the northeastern half of the country. By further combining the hookworm prevalence map, the at-risk population of school-age children requiring integrated schistosomiasis/soil-transmitted helminth treatment regimens according to the coendemicity was estimated. CONCLUSIONS/SIGNIFICANCE: The first comprehensive national mapping of urogenital schistosomiasis in Sierra Leone was conducted. Using a new method for calculating the combined prevalence of schistosomiasis using estimates from two separate surveys, we provided a robust coendemicity mapping for overall urogenital and intestinal schistosomiasis. We also produced a coendemicity map of schistosomiasis and hookworm. These coendemicity maps can be used to guide the decision making for MDA strategies in combination

  20. Prevalence of Schistosoma mansoni infection and the therapeutic efficacy of praziquantel among school children in Manna District, Jimma Zone, southwest Ethiopia

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    Mitiku Bajiro

    2016-10-01

    Full Text Available Abstract Background Intestinal schistosomiasis is one of the neglected tropical parasitic diseases caused by Schistosoma mansoni. Currently, the control measures for the disease are mainly based on mass drug administration (MDA with praziquantel (PZQ targeting the school-age children. In Ethiopia, the potential foci for schistosomiasis and therapeutic efficacy of PZQ among school-age children remain poorly explored. Therefore, we determined both the prevalence and intensity of S. mansoni infection and the therapeutic efficacy of PZQ among school children in the Manna District (new foci for S. mansoni, Jimma Zone, southwest Ethiopia. Methods A cross-sectional study was conducted among the school children aged between 6 and 18 years in three primary schools in Manna district from March to April 2014. For diagnosis of S. mansoni, a single stool sample was obtained from each child and processed using single Kato Katz and examined under light microscopy. A questionnaire was used to collect demographic information of the school children participated in the study. School children excreting eggs of S. mansoni were administered with 40 mg/kg of PZQ and re-examined after three weeks post-treatment. The therapeutic efficacy of PZQ against S. mansoni was evaluated by means of cure rate and egg reduction rate. Results The overall prevalence of S. mansoni among the school children in the three primary schools in Manna District was 24.0 %. Higher prevalence was recorded for males 25.6 % (61/238 than for females 22.5 % (59/262. Majority (27.5 % of infection intensity was light with mean faecal egg count (FEC of 202 eggs per gram (EPG. The therapeutic efficacy of PZQ at a dose of 40 mg/kg was highly efficient (cure rate of 99.1 % and egg reduction rate of 99.9 % among the school children in the three primary schools in Manna District. Conclusions The school children in the three primary schools of Manna District, Jimma Zone were at moderate risk of the

  1. Flavonoids and Sesquiterpene Lactones from Artemisia absinthium and Tanacetum parthenium against Schistosoma mansoni Worms.

    Science.gov (United States)

    de Almeida, Luísa Maria Silveira; de Carvalho, Lara Soares Aleixo; Gazolla, Matheus Coutinho; Silva Pinto, Pedro Luiz; da Silva, Marcos Paulo Nascimento; de Moraes, Josué; Da Silva Filho, Ademar A

    2016-01-01

    Human schistosomiasis, caused by trematode worms of the genus Schistosoma, is one of the most significant neglected tropical diseases, affecting more than 200 million individuals worldwide and praziquantel is the only available drug to treat this disease. Artemisia absinthium L. and Tanacetum parthenium L. are species popularly used as anthelmintics. We investigated the in vitro schistosomicidal activity of crude extracts of A. absinthium (AA) and T. parthenium (TP) and their isolated compounds. AA and TP, at 200 μg/mL, were active, causing 100% mortality of all adult worms. Chromatographic fractionation of AA leads to isolation of artemetin and hydroxypelenolide, while santin, apigenin, and parthenolide were isolated from TP. Artemetin, hydroxypelenolide, santin, and apigenin, at 100 μM, were inactive against adult worms. Parthenolide (12.5 to 100 μM) caused 100% mortality, tegumental alterations, and reduction of motor activity of all adult worms of S. mansoni, without affecting mammalian cells. Confocal laser scanning microscopy showed tegumental morphological alterations and changes on the numbers of tubercles of S. mansoni worms. This report provides the first evidence for the in vitro activity of parthenolide against adult worms of S. mansoni, opening the route to further schistosomicidal studies with this compound.

  2. Activation-induced apoptosis in peripheral blood mononuclear cells during hepatosplenic Schistosoma mansoni infections.

    Science.gov (United States)

    Ghoneim, H M; Demian, S R; Heshmat, M G; Ismail, N S; El-Sayed, Laila H

    2008-01-01

    It is well established that programmed cell death (apoptosis) is an important regulator of host responses during infection with a variety of intra- and extra-cellular pathogens. The present work aimed at assessment of in vitro spontaneous and phytohemagglutinin (PHA)-induced apoptosis in mononuclear cells isolated from patients with hepatosplenic form of S. mansoni infections. Cell death data were correlated to the degree of lymphoproliferative responses to PHA as well as to the serum anti-schistosomal antibody titers. A markedly significant increase in PHA-induced apoptosis in lymphocytes isolated from S. mansoni-infected patients was seen when compared to the corresponding healthy controls. However, a slight difference was recorded between the two studied groups regarding the spontaneous apoptosis. This was accompanied with a significant impairment of in vitro PHA-induced lymphoproliferation of T cells from S. mansoni patients. Data of the present study supports the hypothesis that activation-induced cell death (AICD) is a potentially contributing factor in T helper (Th) cell regulation during chronic stages of schistosomiasis, which represents a critically determinant factor in the host-parasite interaction and might influence the destiny of parasitic infections either towards establishment of chronic infection or towards host death.

  3. A comparative chemogenomics strategy to predict potential drug targets in the metazoan pathogen, Schistosoma mansoni.

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    Conor R Caffrey

    Full Text Available Schistosomiasis is a prevalent and chronic helmintic disease in tropical regions. Treatment and control relies on chemotherapy with just one drug, praziquantel and this reliance is of concern should clinically relevant drug resistance emerge and spread. Therefore, to identify potential target proteins for new avenues of drug discovery we have taken a comparative chemogenomics approach utilizing the putative proteome of Schistosoma mansoni compared to the proteomes of two model organisms, the nematode, Caenorhabditis elegans and the fruitfly, Drosophila melanogaster. Using the genome comparison software Genlight, two separate in silico workflows were implemented to derive a set of parasite proteins for which gene disruption of the orthologs in both the model organisms yielded deleterious phenotypes (e.g., lethal, impairment of motility, i.e., are essential genes/proteins. Of the 67 and 68 sequences generated for each workflow, 63 were identical in both sets, leading to a final set of 72 parasite proteins. All but one of these were expressed in the relevant developmental stages of the parasite infecting humans. Subsequent in depth manual curation of the combined workflow output revealed 57 candidate proteins. Scrutiny of these for 'druggable' protein homologs in the literature identified 35 S. mansoni sequences, 18 of which were homologous to proteins with 3D structures including co-crystallized ligands that will allow further structure-based drug design studies. The comparative chemogenomics strategy presented generates a tractable set of S. mansoni proteins for experimental validation as drug targets against this insidious human pathogen.

  4. Flavonoids and Sesquiterpene Lactones from Artemisia absinthium and Tanacetum parthenium against Schistosoma mansoni Worms

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    Luísa Maria Silveira de Almeida

    2016-01-01

    Full Text Available Human schistosomiasis, caused by trematode worms of the genus Schistosoma, is one of the most significant neglected tropical diseases, affecting more than 200 million individuals worldwide and praziquantel is the only available drug to treat this disease. Artemisia absinthium L. and Tanacetum parthenium L. are species popularly used as anthelmintics. We investigated the in vitro schistosomicidal activity of crude extracts of A. absinthium (AA and T. parthenium (TP and their isolated compounds. AA and TP, at 200 μg/mL, were active, causing 100% mortality of all adult worms. Chromatographic fractionation of AA leads to isolation of artemetin and hydroxypelenolide, while santin, apigenin, and parthenolide were isolated from TP. Artemetin, hydroxypelenolide, santin, and apigenin, at 100 μM, were inactive against adult worms. Parthenolide (12.5 to 100 μM caused 100% mortality, tegumental alterations, and reduction of motor activity of all adult worms of S. mansoni, without affecting mammalian cells. Confocal laser scanning microscopy showed tegumental morphological alterations and changes on the numbers of tubercles of S. mansoni worms. This report provides the first evidence for the in vitro activity of parthenolide against adult worms of S. mansoni, opening the route to further schistosomicidal studies with this compound.

  5. Comparison of Schistosoma mansoni soluble cercarial antigens and soluble egg antigens for serodiagnosing schistosome infections.

    Science.gov (United States)

    Smith, Huw; Doenhoff, Mike; Aitken, Cara; Bailey, Wendi; Ji, Minjun; Dawson, Emily; Gilis, Henk; Spence, Grant; Alexander, Claire; van Gool, Tom

    2012-01-01

    A Schistosoma mansoni cercarial antigen preparation (cercarial transformation fluid--SmCTF) was evaluated for detection of anti-schistosome antibodies in human sera in 4 collaborating laboratories. The performance of SmCTF was compared with that of S. mansoni egg antigens (SmSEA) in an indirect enzyme-immunoassay (ELISA) antigen assay, the latter being used routinely in 3 of the 4 participating laboratories to diagnose S. mansoni and S. haematobium infections. In the fourth laboratory the performance of SmCTF was compared with that of S. japonicum egg antigens (SjSEA) in ELISA for detection of anti-S. japonicum antibodies. In all 4 laboratories the results given by SmCTF in ELISA were very similar to those given by the antigen preparation routinely used in the respective laboratory to detect anti-schistosome antibodies in human infection sera. In so far as the ELISA results from SmCTF are thus so little different from those given by schistosome egg antigens and also cheaper to produce, the former is a potentially useful new diagnostic aid for schistosomiasis.

  6. Comparison of Schistosoma mansoni soluble cercarial antigens and soluble egg antigens for serodiagnosing schistosome infections.

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    Huw Smith

    Full Text Available A Schistosoma mansoni cercarial antigen preparation (cercarial transformation fluid--SmCTF was evaluated for detection of anti-schistosome antibodies in human sera in 4 collaborating laboratories. The performance of SmCTF was compared with that of S. mansoni egg antigens (SmSEA in an indirect enzyme-immunoassay (ELISA antigen assay, the latter being used routinely in 3 of the 4 participating laboratories to diagnose S. mansoni and S. haematobium infections. In the fourth laboratory the performance of SmCTF was compared with that of S. japonicum egg antigens (SjSEA in ELISA for detection of anti-S. japonicum antibodies. In all 4 laboratories the results given by SmCTF in ELISA were very similar to those given by the antigen preparation routinely used in the respective laboratory to detect anti-schistosome antibodies in human infection sera. In so far as the ELISA results from SmCTF are thus so little different from those given by schistosome egg antigens and also cheaper to produce, the former is a potentially useful new diagnostic aid for schistosomiasis.

  7. Scrotal Swelling and Testicular Atrophy due to Schistosomiasis in a 9-Year-Old Boy: A Case Report

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    Peter F. Rambau

    2011-01-01

    Full Text Available Schistosomiasis is a communicable disease which commonly involves urinary bladder causing hematuria, or large bowel causing bloody stool. The common species encountered in this lake region surrounding Lake Victoria in Tanzania are Schistosoma haematobium and Schistosoma mansoni. Complications can lead to portal hypertension due portal fibrosis in liver, and fibrosis in lung can lead to pulmonary hypertension; this commonly seen with S. mansoni. Major complications of S. maeametobium are chronic cystitis with squamous metaplasia with subsequent development of squamous cell carcinoma. Involvement of spinal cord causing paraplegia has been observed in S. haematobium. Other unusual pathology of schistosomiasis has been described, such as involvement of the appendix, ovary, prostate, and cervix. Here, we present a case of schistosomiasis in a 9-year-old boy who presented with left scrotal pain for one year which was accompanied by scrotal swelling; surgical exploration was done, and the finding was hydrocele and atrophic testes with nodules on the surface. Histological examination reveals atrophic testis and heavy active granulomatous inflammation with schistosoma eggs consistent with Schistosoma haematobium in the tunica vaginalis.

  8. Effect of praziquantel treatment of Schistosoma mansoni during pregnancy on intensity of infection and antibody responses to schistosome antigens

    DEFF Research Database (Denmark)

    Tweyongyere, Robert; Mawa, Patrice A.; Emojong, Nicholas O.

    2009-01-01

    Background Praziquantel treatment of schistosomiasis during pregnancy was only recommended in 2002; hence the effects of treatment during pregnancy are not fully known. We have therefore evaluated the effects on infection intensity and the immunological effects of praziquantel treatment against...... after delivery. Infection intensity after treatment was assessed by a single Kato-Katz examination of stool samples with duplicate slides and categorised as undetected, light (1-99 eggs per gram (epg)), moderate (100-399 epg) or heavy (=400 epg). Antibodies against S. mansoni worm and egg antigens were......E, but these boosts were less pronounced than in women whose treatment was delayed until after delivery. Praziquantel had limited effects on antibodies against egg antigens. Conclusion S mansoni antigen-specific antibody levels and praziquantel-induced boosts in antibody levels were broadly suppressed during...

  9. Susceptibility of Nectomys rattus (Pelzen, 1883 to experimental infection with Schistosoma mansoni (Sambon, 1907: a potential reservoir in Brazil

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    Ribeiro Ana Cláudia

    1998-01-01

    Full Text Available The aim of the present research was to evaluate the potential of Nectomys rattus, the "water rat", to develop Schistosoma mansoni infection. Comparison with N. squamipes was carried out. Both species of rodents were submitted to transcutaneous infection using different infective cercariae loads: 50, 100 or 500. N. rattus showed high susceptibility to S. mansoni, with an infection rate of 71%. Rodents were able to excrete viable eggs of S. mansoni in the feaces during all infection period. For both species, the small intestine, followed by the liver and the large intestine, presented the highest concentration of eggs among the surveyed organs. Infection caused no animal death. Moreover, N. rattus accomplished the parasite's life cycle, by infecting the snails Biomphalaria glabrata and later Mus musculus. These evidences indicate that both N. rattus, as for N. squamipes are potential reservoirs for schistosomiasis in Brazil. Considering the fact that N. rattus and N. squamipes exist in the same natural ecosystems of S. mansoni, we suggest that these rodents must be regarded as influential factors in epidemiology surveys.

  10. Evaluation of the Anti-schistosomal Effects of Turmeric (Curcuma longa Versus Praziquantel in Schistosoma mansoni Infected Mice

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    Atef HUSSEIN

    2017-12-01

    Full Text Available AbstractBackground: Curcumin is the major active ingredient of Curcuma longa L., traditionally known as turmeric and has been shown to exhibit a wide range of pharmacological activities including anti-parasitic effect. However, it is found to be water-insoluble and has low bioavailability. The aim of this study was to explore the potential role of turmeric solved in olive oil either alone or in combination with praziquantel (PZQ in treatment of schistosomiasis mansoni.Methods: The whole turmeric powder suspended in olive oil (as a solvent is indicated to S. mansoni-infected mice aiming to study its potential therapeutic role, either alone or in combination with PZQ.Results: Turmeric significantly reduced S. mansoni worm burden and complete absence of adult worms achieved in mice treated with combination of turmeric and PZQ. Turmeric has slight non-significant effect on the oogram pattern in all examined S. mansoni infected mice. Turmeric and PZQ found to exert a significant reduction of granuloma size in comparison with control. However, turmeric has a non-significant effect on granuloma number. On the other hand, turmeric or/and PZQ treated mice showed obvious improvement of pathology with mild cloudy swelling and less hydropic degeneration.Conclusion: Turmeric significantly reduced parasite worm burden, granuloma size and consequently the pathology of affected liver, it still far less effective than PZQ.

  11. Cerebral schistosomiasis | Ravi | SA Journal of Radiology

    African Journals Online (AJOL)

    Although schistosomiasis (bilharzia) is one of the most common parasitic infections in humans, schistosomal infection of the nervous system is rare. This report is of an unusual case of primary cerebral schistosomiasis and describes its magnetic resonance imaging appearance.

  12. Prevalence of urinary schistosomiasis among secondary school ...

    African Journals Online (AJOL)

    Prevalence of urinary schistosomiasis among secondary school students in Ibadan, Nigeria. ... The inclusion of health education package aimed at changing behavior of school children from adverse water contact practices was recommended. Keywords: prevalence, urinary schistosomiasis, secondary school students.

  13. New insights into the molecular epidemiology and population genetics of Schistosoma mansoni in Ugandan pre-school children and mothers.

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    Martha Betson

    Full Text Available Significant numbers of pre-school children are infected with Schistosoma mansoni in sub-Saharan Africa and are likely to play a role in parasite transmission. However, they are currently excluded from control programmes. Molecular phylogenetic studies have provided insights into the evolutionary origins and transmission dynamics of S. mansoni, but there has been no research into schistosome molecular epidemiology in pre-school children. Here, we investigated the genetic diversity and population structure of S. mansoni in pre-school children and mothers living in lakeshore communities in Uganda and monitored for changes over time after praziquantel treatment. Parasites were sampled from children (<6 years and mothers enrolled in the longitudinal Schistosomiasis Mothers and Infants Study at baseline and at 6-, 12- and 18-month follow-up surveys. 1347 parasites from 35 mothers and 45 children were genotyped by direct sequencing of the cytochrome c oxidase (cox1 gene. The cox1 region was highly diverse with over 230 unique sequences identified. Parasite populations were genetically differentiated between lakes and non-synonymous mutations were more diverse at Lake Victoria than Lake Albert. Surprisingly, parasite populations sampled from children showed a similar genetic diversity to those sampled from mothers, pointing towards a non-linear relationship between duration of exposure and accumulation of parasite diversity. The genetic diversity six months after praziquantel treatment was similar to pre-treatment diversity. Our results confirm the substantial genetic diversity of S. mansoni in East Africa and provide significant insights into transmission dynamics within young children and mothers, important information for schistosomiasis control programmes.

  14. Further evaluation of an updated PCR assay for the detection of Schistosoma mansoni DNA in human stool samples

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    Luciana I Gomes

    2009-12-01

    Full Text Available A previously reported sensitive PCR assay for the detection of Schistosoma mansoni DNA was updated and evaluated. Changes in the DNA extraction method, including the use of a worldwide available commercial kit and the inclusion of additional quality control measures, increased the robustness of the test, as confirmed by the analysis of 67 faecal samples from an endemic area in Brazil. The PCR assay is at hand as a proven, reliable diagnostic test for the control of schistosomiasis in specific settings.

  15. Prevalence of urinary schistosomiasis and associated haemato ...

    African Journals Online (AJOL)

    Schistosomiasis was found to be associated with hematuria (97.3%) and proteinuria (79.6%). Conclusion: Haematuria and proteinuria have a potential value in the screening for community diagnosis of urinary schistosomiasis in endemic areas. Vesical schistosomiasis is recognized as a significant public health problem ...

  16. The role of the immunological background of mice in the genetic variability of Schistosoma mansoni as detected by random amplification of polymorphic DNA.

    Science.gov (United States)

    Cossa-Moiane, I L; Mendes, T; Ferreira, T M; Mauricio, I; Calado, M; Afonso, A; Belo, S

    2015-11-01

    Schistosomiasis is a parasitic disease caused by flatworms of the genus Schistosoma. Among the Schistosoma species known to infect humans, S. mansoni is the most frequent cause of intestinal schistosomiasis in sub-Saharan Africa and South America: the World Health Organization estimates that about 200,000 deaths per year result from schistosomiasis in sub-Saharan Africa alone. The Schistosoma life cycle requires two different hosts: a snail as intermediate host and a mammal as definitive host. People become infected when they come into contact with water contaminated with free-living larvae (e.g. when swimming, fishing, washing). Although S. mansoni has mechanisms for escaping the host immune system, only a minority of infecting larvae develop into adults, suggesting that strain selection occurs at the host level. To test this hypothesis, we compared the Belo Horizonte (BH) strain of S. mansoni recovered from definitive hosts with different immunological backgrounds using random amplification of polymorphic DNA-polymerase chain reaction (RAPD-PCR). Schistosoma mansoni DNA profiles of worms obtained from wild-type (CD1 and C57BL/6J) and mutant (Jα18- / - and TGFβRIIdn) mice were analysed. Four primers produced polymorphic profiles, which can therefore potentially be used as reference biomarkers. All male worms were genetically distinct from females isolated from the same host, with female worms showing more specific fragments than males. Of the four host-derived schistosome populations, female and male adults recovered from TGFβRIIdn mice showed RAPD-PCR profiles that were most similar to each other. Altogether, these data indicate that host immunological backgrounds can influence the genetic diversity of parasite populations.

  17. Selecting targets for the diagnosis of Schistosoma mansoni infection: An integrative approach using multi-omic and immunoinformatics data

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    Siqueira, Liliane M. V.; Lopes, Marcelo D.; Lopes, Débora O.; Coelho, Paulo Marcos Z.; Teixeira-Carvalho, Andréa

    2017-01-01

    In order to effectively control and monitor schistosomiasis, new diagnostic methods are essential. Taking advantage of computational approaches provided by immunoinformatics and considering the availability of Schistosoma mansoni predicted proteome information, candidate antigens of schistosomiasis were selected and used in immunodiagnosis tests based on Enzime-linked Immunosorbent Assay (ELISA). The computational selection strategy was based on signal peptide prediction; low similarity to human proteins; B- and T-cell epitope prediction; location and expression in different parasite life stages within definitive host. Results of the above-mentioned analysis were parsed to extract meaningful biological information and loaded into a relational database developed to integrate them. In the end, seven proteins were selected and one B-cell linear epitope from each one of them was selected using B-cell epitope score and the presence of intrinsically disordered regions (IDRs). These predicted epitopes generated synthetic peptides that were used in ELISA assays to validate the rational strategy of in silico selection. ELISA was performed using sera from residents of areas of low endemicity for S. mansoni infection and also from healthy donors (HD), not living in an endemic area for schistosomiasis. Discrimination of negative (NEG) and positive (INF) individuals from endemic areas was performed using parasitological and molecular methods. All infected individuals were treated with praziquantel, and serum samples were obtained from them 30 and 180 days post-treatment (30DPT and 180DPT). Results revealed higher IgG levels in INF group than in HD and NEG groups when peptides 1, 3, 4, 5 and 7 were used. Moreover, using peptide 5, ELISA achieved the best performance, since it could discriminate between individuals living in an endemic area that were actively infected from those that were not (NEG, 30DPT, 180DPT groups). Our experimental results also indicate that the

  18. Association of Eumycetoma and Schistosomiasis

    Science.gov (United States)

    van Hellemond, Jaap J.; Vonk, Alieke G.; de Vogel, Corné; Koelewijn, Rob; Vaessen, Norbert; Fahal, Ahmed H.; van Belkum, Alex; van de Sande, Wendy W. J.

    2013-01-01

    Eumycetoma is a morbid chronic granulomatous subcutaneous fungal disease. Despite high environmental exposure to this fungus in certain regions of the world, only few develop eumycetoma for yet unknown reasons. Animal studies suggest that co-infections skewing the immune system to a Th2-type response enhance eumycetoma susceptibility. Since chronic schistosomiasis results in a strong Th2-type response and since endemic areas for eumycetoma and schistosomiasis do regionally overlap, we performed a serological case-control study to identify an association between eumycetoma and schistosomiasis. Compared to endemic controls, eumycetoma patients were significantly more often sero-positive for schistosomiasis (p = 0.03; odds ratio 3.2, 95% CI 1.18–8.46), but not for toxoplasmosis, an infection inducing a Th1-type response (p = 0.6; odds ratio 1.5, 95% CI 0.58–3.83). Here, we show that schistosomiasis is correlated to susceptibility for a fungal disease for the first time. PMID:23717704

  19. [Radiculomyelopathy in schistosomiasis].

    Science.gov (United States)

    Detzler, J; Backes, H; Guldner, J

    2017-11-16

    The increasing migration of people from their homeland in far distant regions to Europe in the last few years has strongly influenced the rise of previously rarely seen diseases. They not only originate from the respective homeland but also from the transit countries during the migration process. We report the case of a 27-year-old male migrant from Eritrea, who after months of flight as a refugee travelling through various African countries, presented at our hospital with a progressive, painful radiculopathy. Whole spine magnetic resonance imaging (MRI) showed a focus located in the myelon, extending from T11 to the medullary conus. The differential diagnostic clarification ultimately revealed an infection with Schistosoma mansoni. After guideline-conform treatment with praziquantel for 3 days and additional administration of corticosteroids for 3 months, a slow regression of the findings and improvement of the symptoms could be shown clinically and by MRI. This case study shows the importance of taking the medical history and that a closer look at the potential exposure in the homeland and transit countries should be of great benefit in reaching the diagnosis, especially in patients with a migration background.

  20. Enhanced protective efficacy of a chimeric form of the schistosomiasis vaccine antigen Sm-TSP-2.

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    Mark S Pearson

    Full Text Available The large extracellular loop of the Schistosoma mansoni tetraspanin, Sm-TSP-2, when fused to a thioredoxin partner and formulated with Freund's adjuvants, has been shown to be an efficacious vaccine against murine schistosomiasis. Moreover, Sm-TSP-2 is uniquely recognised by IgG(1 and IgG(3 from putatively resistant individuals resident in S. mansoni endemic areas in Brazil. In the present study, we expressed Sm-TSP-2 at high yield and in soluble form in E. coli without the need for a solubility enhancing fusion partner. We also expressed in E. coli a chimera called Sm-TSP-2/5B, which consisted of Sm-TSP-2 fused to the immunogenic 5B region of the hookworm aspartic protease and vaccine antigen, Na-APR-1. Sm-TSP-2 formulated with alum/CpG showed significant reductions in adult worm and liver egg burdens in two separate murine schistosomiasis challenge studies. Sm-TSP-2/5B afforded significantly greater protection than Sm-TSP-2 alone when both antigens were formulated with alum/CpG. The enhanced protection obtained with the chimeric fusion protein was associated with increased production of anti-Sm-TSP-2 antibodies and IL-4, IL-10 and IFN-γ from spleen cells of vaccinated animals. Sera from 666 individuals from Brazil who were infected with S. mansoni were screened for potentially deleterious IgE responses to Sm-TSP-2. Anti-Sm-TSP-2 IgE to this protein was not detected (also shown previously for Na-APR-1, suggesting that the chimeric antigen Sm-TSP-2/5B could be used to safely and effectively vaccinate people in areas where schistosomes and hookworms are endemic.

  1. Enhanced protective efficacy of a chimeric form of the schistosomiasis vaccine antigen Sm-TSP-2.

    Science.gov (United States)

    Pearson, Mark S; Pickering, Darren A; McSorley, Henry J; Bethony, Jeffrey M; Tribolet, Leon; Dougall, Annette M; Hotez, Peter J; Loukas, Alex

    2012-01-01

    The large extracellular loop of the Schistosoma mansoni tetraspanin, Sm-TSP-2, when fused to a thioredoxin partner and formulated with Freund's adjuvants, has been shown to be an efficacious vaccine against murine schistosomiasis. Moreover, Sm-TSP-2 is uniquely recognised by IgG(1) and IgG(3) from putatively resistant individuals resident in S. mansoni endemic areas in Brazil. In the present study, we expressed Sm-TSP-2 at high yield and in soluble form in E. coli without the need for a solubility enhancing fusion partner. We also expressed in E. coli a chimera called Sm-TSP-2/5B, which consisted of Sm-TSP-2 fused to the immunogenic 5B region of the hookworm aspartic protease and vaccine antigen, Na-APR-1. Sm-TSP-2 formulated with alum/CpG showed significant reductions in adult worm and liver egg burdens in two separate murine schistosomiasis challenge studies. Sm-TSP-2/5B afforded significantly greater protection than Sm-TSP-2 alone when both antigens were formulated with alum/CpG. The enhanced protection obtained with the chimeric fusion protein was associated with increased production of anti-Sm-TSP-2 antibodies and IL-4, IL-10 and IFN-γ from spleen cells of vaccinated animals. Sera from 666 individuals from Brazil who were infected with S. mansoni were screened for potentially deleterious IgE responses to Sm-TSP-2. Anti-Sm-TSP-2 IgE to this protein was not detected (also shown previously for Na-APR-1), suggesting that the chimeric antigen Sm-TSP-2/5B could be used to safely and effectively vaccinate people in areas where schistosomes and hookworms are endemic.

  2. Activity of liver microsomal enzymes during the chronic phase of murine schistosomiasis

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    F.P. Conte

    2007-05-01

    Full Text Available The effects of schistosomiasis on microsomal enzymes were studied on post-infection day 90 when accumulated damage and fibrosis are most intense but granulomatous reaction around the eggs harbored in the liver is smaller than during the earlier phases. Swiss Webster (SW and DBA/2 mice of either sex (N = 12 per sex per group were infected with 100 Schistosoma mansoni cercariae on postnatal day 10 and killed on post-infection day 90. Cytochrome P-450 (CYP concentration and alkoxyresorufin-O-dealkylases (EROD, MROD, BROD, and PROD, p-nitrophenol-hydroxylase (PNPH, coumarin-7-hydroxylase (COH, and UDP-glucuronosyltransferase (UGT activities were measured in hepatic microsomes. Age-matched mice of the same sex and strain were used as controls. In S. mansoni-infected mice, CYP1A- and 2B-mediated activities (control = 100% were reduced in SW (EROD: male (M 36%, female (F 38%; MROD: M 38%, F 39%; BROD: M 46%, F 19%; PROD: M 50%, F 28% and DBA/2 mice (EROD: M 64%, F 58%; MROD: M 60%; BROD: F 49%; PROD: M 73% while PNPH (CYP2E1 was decreased in SW (M 31%, F 38% but not in DBA/2 mice. COH did not differ between infected and control DBA/2 and UGT, a phase-2 enzyme, was not altered by infection. In conclusion, chronic S. mansoni infection reduced total CYP content and all CYP-mediated activities evaluated in SW mice, including those catalyzed by CYP2E1 (PNPH, CYP1A (EROD, MROD and 2B (BROD, PROD. In DBA/2 mice, however, CYP2A5- and 2E1-mediated activities remained unchanged while total CYP content and activities mediated by other CYP isoforms were depressed during chronic schistosomiasis.

  3. Molecular characterization of serine protease inhibitor isoform 3, SmSPI, from Schistosoma mansoni.

    Science.gov (United States)

    Pakchotanon, Pattarakul; Molee, Patamaporn; Nuamtanong, Supaporn; Limpanont, Yanin; Chusongsang, Phiraphol; Limsomboon, Jareemate; Chusongsang, Yupa; Maneewatchararangsri, Santi; Chaisri, Urai; Adisakwattana, Poom

    2016-08-01

    Serine protease inhibitors, known as serpins, are pleiotropic regulators of endogenous and exogenous proteases, and molecule transporters. They have been documented in animals, plants, fungi, bacteria, and viruses; here, we characterize a serpin from the trematode platyhelminth Schistosoma mansoni. At least eight serpins have been found in the genome of S. mansoni, but only two have characterized molecular properties and functions. Here, the function of S. mansoni serpin isoform 3 (SmSPI) was analyzed, using both computational and molecular biological approaches. Phylogenetic analysis showed that SmSPI was closely related to Schistosoma haematobium serpin and Schistosoma japonicum serpin B10. Structure determined in silico confirmed that SmSPI belonged to the serpin superfamily, containing nine α-helices, three β-sheets, and a reactive central loop. SmSPI was highly expressed in schistosomules, predominantly in the head gland, and in adult male and female with intensive accumulation on the spines, which suggests that it may have a role in facilitating intradermal and intravenous survival. Recombinant SmSPI was overexpressed in Escherichia coli; the recombinant protein was of the same size (46 kDa) as the native protein. Immunological analysis suggested that mice infected with S. mansoni responded to rSmSPI at 8 weeks postinfection (wpi) but not earlier. The inhibitory activity of rSmSPI was specific to chymotrypsin but not trypsin, neutrophil elastase, and porcine pancreatic elastase. Elucidating the biological and physiological functions of SmSPI as well as other serpins will lead to further understanding of host-parasite interaction machinery that may provide novel strategies to prevent and control schistosomiasis in the future.

  4. Differential expression of small RNA pathway genes associated with the Biomphalaria glabrata/Schistosoma mansoni interaction

    Science.gov (United States)

    Babá, Élio Hideo; Caldeira, Roberta Lima

    2017-01-01

    The World Health Organization (WHO) estimates that approximately 240 million people in 78 countries require treatment for schistosomiasis, an endemic disease caused by trematodes of the genus Schistosoma. In Brazil, Schistosoma mansoni is the only species representative of the genus whose passage through an invertebrate host, snails of the genus Biomphalaria, is obligatory before infecting a mammalian host, including humans. The availability of the genome and transcriptome of B. glabrata makes studying the regulation of gene expression, particularly the regulation of miRNA and piRNA processing pathway genes, possible. This might assist in better understanding the biology of B. glabrata as well as its relationship to the parasite S. mansoni. Some aspects of this interaction are still poorly explored, including the participation of non-coding small RNAs, such as miRNAs and piRNAs, with lengths varying from 18 to 30 nucleotides in mature form, which are potent regulators of gene expression. Using bioinformatics tools and quantitative PCR, we characterized and validated the miRNA and piRNA processing pathway genes in B. glabrata. In silico analyses showed that genes involved in miRNA and piRNA pathways were highly conserved in protein domain distribution, catalytic site residue conservation and phylogenetic analysis. Our study showed differential expression of putative Argonaute, Drosha, Piwi, Exportin-5 and Tudor genes at different snail developmental stages and during infection with S. mansoni, suggesting that the machinery is required for miRNA and piRNA processing in B. glabrata at all stages. These data suggested that the silencing pathway mediated by miRNAs and piRNAs can interfere in snail biology throughout the life cycle of the snail, thereby influencing the B. glabrata/S. mansoni interaction. Further studies are needed to confirm the participation of the small RNA processing pathway proteins in the parasite/host relationship, mainly the effective

  5. Surgical hepatosplenic mansonic schistosomiasis in adolescents: repercussions of the post-treatment schistosomotic burden on the hepatic functional reserve

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    Carlos Teixeira Brandt

    2001-09-01

    Full Text Available Schistosomiasis mansoni affects the hepatic functional reserve. Clinical treatment with oxamniquine is not 100% effective and there has been found strain of this parasite resistant to this drug. The aims of this investigation were: (1 to examine the presence of residual parasite burden after medical and surgical treatment on adolescents with surgical schistosomiasis mansoni and (2 to assess the effect on the hepatic functional reserve in patients with and without residual infection. Twenty nine children with hepatosplenic schistosomiasis mansoni and bleeding esophageal varices were treated with oxamniquine. They underwent splenectomy, ligature of the left gastric vein and autologous implantation of spleen tissue into the greater omentum. After a mean post-operative follow up of five years they underwent rectal biopsy for schistosomotic egg search. They were divided in patients with and without infection. In 20 patients the submucosal egg search was negative, however, in 9 it was positive. The hepatic functional reserve in the patients without infection was as follows: 17 were Child-Pugh A and 3 Child-Pugh B. In the patients who were still infected 6 were Child-Pugh A and 3 Child-Pugh B. The chi2 analysis of the hepatic functional reserve showed chi2 = 3.19 - p= 0.07. From the results the following conclusion can be drawn: residual infection or reinfection in the follow up period had not interfered with the distribution of the hepatic functional reserve of the patients in this series. However, there was a trend for a decrease of this parameter in patients with residual infection.

  6. Schistosomes of small mammals from the Lake Victoria Basin, Kenya: new species, familiar species, and implications for schistosomiasis control.

    Science.gov (United States)

    Hanelt, B; Mwangi, I N; Kinuthia, J M; Maina, G M; Agola, L E; Mutuku, M W; Steinauer, M L; Agwanda, B R; Kigo, L; Mungai, B N; Loker, E S; Mkoji, G M

    2010-06-01

    Recent schistosomiasis control efforts in sub-Saharan Africa have focused nearly exclusively on treatment of humans with praziquantel. However, the extent to which wild mammals act as reservoirs for Schistosoma mansoni and therefore as sources of renewed transmission following control efforts is poorly understood. With the objective to study the role of small mammals as reservoir hosts, 480 animals belonging to 9 rodent and 1 insectivore species were examined for infection with schistosomes in Kisumu, in the Lake Victoria Basin, Kenya. Animals were collected from 2 sites: near the lakeshore and from Nyabera Marsh draining into the lake. A total of 6.0% of the animals captured, including 5 murid rodent species and 1 species of shrew (Crocidura olivieri) were infected with schistosomes. Four schistosome species were recovered and identified using cox1 DNA barcoding: S. mansoni, S. bovis, S. rodhaini and S. kisumuensis, the latter of which was recently described from Nyabera Marsh. Schistosoma mansoni and S. rodhaini were found infecting the same host individual (Lophuromys flavopunctatus), suggesting that this host species could be responsible for the production of hybrid schistosomes found in the area. Although the prevalence of S. mansoni infection in these reservoir populations was low (1.5%), given their potentially vast population size, their impact on transmission needs further study. Reservoir hosts could perpetuate snail infections and favour renewed transmission to humans once control programmes have ceased.

  7. Inflammation, oxidative stress and L-fucose as indispensable participants in schistosomiasis-associated colonic dysplasia.

    Science.gov (United States)

    Soliman, Nema Ali; Keshk, Walaa Arafa; Shoheib, Zeinab Salah; Ashour, Dalia Salah; Shamloula, Maha Moustafa

    2014-01-01

    Schistosomiasis is a parasitic disease causing chronic ill health in humans with a serious consequences for socio-economic development in tropical and subtropical regions. There is also evidence linking Schistosoma mansoni to colonic carcinoma occurrence. The aim of this study was to evaluate some inflammatory and oxidative stress biomarkers, as well as L-fucose as linkers between intestinal schistosomiasis and colonic dysplasia development in mice. This study was conducted upon 80 mice that were divided the control group (10 non infected mice) and infected group which was subdivided into 7 sub-groups (10 mice each) according to the time of sacrifaction in the post infection (p.i.) period, 10 mice being sacrificed every two weeks from 6 weeks p.i. to 18 weeks p.i. Tumor necrosis factor alpha (TNF-α), inducible nitric oxide synthase (iNOS), and pentraxin 3 (PTX3) levels were estimated by immunoassay. The L-fucose level, and thioredoxin reductase (TrxR) and lactate dehydrogenase (LDH) activities were also evaluated in colonic tissue. The current study revealed statistically significant elevation in the studied biochemical markers especially at 16 and 18 weeks p.i. The results were confirmed by histopathological examination that revealed atypical architectural and cytological changes in the form of epithelial surface serration and nuclear hyper-chromatizia at 14, 16 and 18 weeks p.i. inflammation, oxidative stress and L-fucose together may form an important link between Schistosomal mansoni infection and colonic dysplasia and they can be new tools for prediction of colonic dysplasia development in experimental schistosomiasis.

  8. Knowledge attitudes and practices of grade three primary schoolchildren in relation to schistosomiasis, soil transmitted helminthiasis and malaria in Zimbabwe

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    Brouwer Kimberly C

    2011-06-01

    Full Text Available Abstract Background Helminth infection rates in grade three children are used as proxy indicators of community infection status and to guide treatment strategies in endemic areas. However knowledge, attitudes and practices (KAP of this target age group (8-10 years in relation to schistosomiasis, soil transmitted helminthiasis (STHs and malaria is not known at a time when integrated plasmodium - helminth control strategies are being advocated. This study sought to assess KAP of grade 3 children in relation to schistosomiasis, STHs and malaria in order to establish an effective school based health education for disease transmission control. Methods Grade 3 children (n = 172 attending four randomly selected primary schools (one in rural and 3 in the commercial farming areas in Zimbabwe were interviewed using a pre-tested interviewer administered questionnaire. The urine filtration technique was used to determine S. haematobium infection status. Infection with S. mansoni and STHs was determined using a combination of results from the Kato Katz and formol ether concentration techniques. P. falciparum was diagnosed by examination of Giemsa stained thick blood smears. Results It was observed that 32.0%, 19.2% and 4.1% of the respondents had correct knowledge about the causes of schistosomiasis, malaria and STHs, respectively, whilst 22.1%, 19.2% and 5.8% knew correct measures to control schistosomiasis, malaria and STHs. Sixty-two percent and 44.8% did not use soap to wash hands after toilet and before eating food respectively, whilst 33.1% never wore shoes. There were no functional water points and soap for hand washing after toilet at all schools. There was a high prevalence distribution of all parasites investigated in this study at Msapa primary school - S. haematobium (77.8%, S. mansoni (33.3% hookworms (29.6% and P. falciparum (48.1%. Reports that participant had suffered from schistosomiasis and malaria before were significant predictors of

  9. The Schistosoma mansoni phylome: using evolutionary genomics to gain insight into a parasite's biology.

    Science.gov (United States)

    Silva, Larissa Lopes; Marcet-Houben, Marina; Nahum, Laila Alves; Zerlotini, Adhemar; Gabaldón, Toni; Oliveira, Guilherme

    2012-11-13

    Schistosoma mansoni is one of the causative agents of schistosomiasis, a neglected tropical disease that affects about 237 million people worldwide. Despite recent efforts, we still lack a general understanding of the relevant host-parasite interactions, and the possible treatments are limited by the emergence of resistant strains and the absence of a vaccine. The S. mansoni genome was completely sequenced and still under continuous annotation. Nevertheless, more than 45% of the encoded proteins remain without experimental characterization or even functional prediction. To improve our knowledge regarding the biology of this parasite, we conducted a proteome-wide evolutionary analysis to provide a broad view of the S. mansoni's proteome evolution and to improve its functional annotation. Using a phylogenomic approach, we reconstructed the S. mansoni phylome, which comprises the evolutionary histories of all parasite proteins and their homologs across 12 other organisms. The analysis of a total of 7,964 phylogenies allowed a deeper understanding of genomic complexity and evolutionary adaptations to a parasitic lifestyle. In particular, the identification of lineage-specific gene duplications pointed to the diversification of several protein families that are relevant for host-parasite interaction, including proteases, tetraspanins, fucosyltransferases, venom allergen-like proteins, and tegumental-allergen-like proteins. In addition to the evolutionary knowledge, the phylome data enabled us to automatically re-annotate 3,451 proteins through a phylogenetic-based approach rather than solely sequence similarity searches. To allow further exploitation of this valuable data, all information has been made available at PhylomeDB (http://www.phylomedb.org). In this study, we used an evolutionary approach to assess S. mansoni parasite biology, improve genome/proteome functional annotation, and provide insights into host-parasite interactions. Taking advantage of a proteome

  10. Utility of repeated praziquantel dosing in the treatment of schistosomiasis in high-risk communities in Africa: a systematic review.

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    Charles H King

    2011-09-01

    Full Text Available Controversy persists about the optimal approach to drug-based control of schistosomiasis in high-risk communities. In a systematic review of published studies, we examined evidence for incremental benefits from repeated praziquantel dosing, given 2 to 8 weeks after an initial dose, in Schistosoma-endemic areas of Africa.We performed systematic searches of electronic databases PubMed and EMBASE for relevant data using search terms 'schistosomiasis', 'dosing' and 'praziquantel' and hand searches of personal collections and bibliographies of recovered articles. In 10 reports meeting study criteria, improvements in parasitological treatment outcomes after two doses of praziquantel were greater for S. mansoni infection than for S. haematobium infection. Observed cure rates (positive to negative conversion in egg detection assays were, for S. mansoni, 69-91% cure after two doses vs. 42-79% after one dose and, for S. haematobium, 46-99% cure after two doses vs. 37-93% after a single dose. Treatment benefits in terms of reduction in intensity (mean egg count were also different for the two species-for S. mansoni, the 2-dose regimen yielded an weighted average 89% reduction in standardized egg counts compared to a 83% reduction after one dose; for S. haematobium, two doses gave a 93% reduction compared to a 94% reduction with a single dose. Cost-effectiveness analysis was performed based on Markov life path modeling.Although schedules for repeated treatment with praziquantel require greater inputs in terms of direct costs and community participation, there are incremental benefits to this approach at an estimated cost of $153 (S. mansoni-$211 (S. haematobium per additional lifetime QALY gained by double treatment in school-based programs. More rapid reduction of infection-related disease may improve program adherence, and if, as an externality of the program, transmission can be reduced through more effective coverage, significant additional benefits are

  11. Evaluation of the cytokine mannose-binding lectin as a mediator of periportal fibrosis progression in patients with schistosomiasis

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    Paula Carolina Valença Silva

    2015-06-01

    Full Text Available INTRODUCTION : We hypothesized higher mannose-binding lectin level and classic factors (i.e., age, sex, alcohol consumption, exposure, and specific treatment are associated with the severity of periportal fibrosis in schistosomiasis. METHODS : This cross-sectional study involved 79 patients infected with Schistosoma mansoni with severe or mild/moderate periportal fibrosis. Serum concentrations of mannose-binding lectin were obtained by enzyme-linked immunosorbent assay (ELISA. RESULTS: Higher serum level of mannose-binding lectin was significantly associated with advanced periportal fibrosis. CONCLUSIONS: Mannose-binding lectin may contribute to liver pathology in schistosomiasis and may represent a risk factor for advanced periportal fibrosis in the Brazilian population studied.

  12. Mao Zedong's fight against schistosomiasis.

    Science.gov (United States)

    Fan, Kawai; Lai, Honkei

    2008-01-01

    In 1956, Mao Zedong began a mass campaign against schistosomiasis in the People's Republic of China. The campaign, which integrated mass mobilization, science, agricultural production, local construction projects, and prophylactic measures, was fueled primarily by a determination to accelerate China's agricultural development. The initial success of this campaign encouraged Mao to embark on the next stage of socialism, the Great Leap Forward. As attention was diverted away from schistosomiasis, however, the disease has again become a major burden to the health of the country.

  13. Reinfection immunity in schistosomiasis. With special reference to immunity induced by radiation attenuated Cercariae

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    Kamiya, Haruo

    1987-07-01

    Schistosomiasis is one of the most important parasitic diseases in the world, especially in endemic areas of developing countries. This situation has prompted parasitologist to attempt intensive researches on immune mechanisms, especially those of reinfection immunity associated with eliminating challenge infection. The current knowledge of reinfection immunity against Schistosoma spp. infection was therefore reviewed briefly and discussed with special reference to our data on protective immune responses induced by radiation-attenuated cercarial infection. A recently developed technique of compressed organ autoradiography (COA) has contributed to assessing parasite attrition in immune animals following challenge infection. Our study using COA has demonstrated that major attrition of schistosomula from challenge infection occurs in the skin of CBA/Ca mice vaccinated with 20 Krad gamma radiation-attenuated cercariae of S. mansoni, while in both lungs and liver of similarly vaccinated guinea pig model. Furthermore, gamma-irradiation to cercariae affected their migration potential and surface-antigen profiles. The immunizing stimuli of gamma radiation-attenuated cercariae profoundly affected the expression of responsiveness in vaccinated animals. The change in antigenic profiles and migration potential of those vaccinating population was discussed in relation to the kinetics of reinfection immunity induced in vaccinated amimal models. These works might provide a base line data to develop a practical vaccine for schistosomiasis using defined antigens. It must be emphasized that these vaccines could serve as a practical prophylactic measure for schistosomiasis in the endemic areas, even if the vaccines fail to induce sterilizing immunity. (author). 141 refs.

  14. Macrophage P2X7 Receptor Function Is Reduced during Schistosomiasis: Putative Role of TGF-β1

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    Suellen D’arc Santos Oliveira

    2014-01-01

    Full Text Available Schistosomiasis is a chronic inflammatory disease whose macrophages are involved in immunopathology modulation. Although P2X7 receptor signaling plays an important role in inflammatory responses mediated by macrophages, no reports have examined the role of P2X7 receptors in macrophage function during schistosomiasis. Thus, we evaluated P2X7 receptor function in peritoneal macrophages during schistosomiasis using an ATP-induced permeabilization assay and measurements of the intracellular Ca2+ concentration. ATP treatment induced significantly less permeabilization in macrophages from S. mansoni-infected mice than in control cells from uninfected animals. Furthermore, P2X7-mediated increases in intracellular Ca2+ levels were also reduced in macrophages from infected mice. TGF-β1 levels were increased in the peritoneal cavity of infected animals, and pretreatment of control macrophages with TGF-β1 reduced ATP-induced permeabilization, mimicking the effect of S. mansoni infection. Western blot and qRT-PCR data showed no difference in P2X7 protein and mRNA between uninfected, infected, and TGF-β1-treated groups. However, immunofluorescence analysis revealed reduced cell surface localization of P2X7 receptors in macrophages from infected and TGF-β1-treated mice compared to controls. Therefore, our data suggest that schistosomiasis reduces peritoneal macrophage P2X7 receptor signaling. This effect is likely due to the fact that infected mice have increased levels of TGF-β1, which reduces P2X7 receptor cell surface expression.

  15. Uptake of preventive treatment for intestinal schistosomiasis among school children in Jinja district, Uganda: a cross sectional study.

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    Simon Muhumuza

    Full Text Available BACKGROUND: In Uganda, the current national health sector strategic and investment plan underscores schistosomiasis as one of the diseases targeted for elimination by the year 2015. However, uptake of treatment among school children is unknown but suspected to be low. We estimated the uptake and predictors of preventive treatment with praziquantel. METHODS: In a cross sectional study carried out in Jinja district of Uganda, a random sample of 1,010 children in 12 primary schools was questioned about their uptake of praziquantel, knowledge and perceptions about schistosomiasis, support for taking preventive treatment and the dangers of taking praziquantel. The prevalence and mean intensity of infection with Schistosoma mansoni were determined. RESULTS: Self reported uptake of praziquantel at last mass treatment was 28.2% (95% confidence interval (CI: 22.9%-33.6%. Overall prevalence and mean intensity of S. mansoni infection was 35% (95% CI: 25.4%-37.9% and 116.1 eggs per gram (epg of stool (95% CI: 98.3-137.1 respectively. Uptake of praziquantel was more likely if a child was from a school with high prevalence of infection, had knowledge about schistosomiasis transmission and prevention, and reported teachers' support to take praziquantel. Of the 285 children who took praziquantel, 142 (49.8% developed side effects. Of the 725 children who did not take the drug, 522 (72.0% reported fear of side effects as a major reason for non-uptake. CONCLUSIONS: Uptake of praziquantel in this population is very low. Fear of side effects of praziquantel, lack of knowledge about schistosomiasis transmission and prevention and lack of teacher support are some of the major factors associated with low uptake.

  16. Strongyloides stercoralis disseminated infection and schistosomiasis in an AIDS patient

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    Rodrigo Martins Brandão

    2012-12-01

    Full Text Available Strongyloides stercoralis hyperinfection syndrome is classically associated with impaired host response and implies in an overburden of larvae in its usual cycle. It has been recognized as a severe and potentially fatal condition in immunocompromised individuals, especially those using oral corticosteroids. Infection with Schistosoma mansoni not only increases the susceptibility to HIV infection, but also promotes progression to disease. The association of the most severe forms of strongyloidiasis and AIDS is scarcely described, even more when S. mansoni is also associated. The authors describe a case of a 34-year-old previously healthy male, admitted to the emergency department with a history of hematemesis associated with dyspnea, hemoptysis, and fever. He referred homosexual relations for 6 years. Physical examination showed an ill-looking patient, and was remarkable for tachycardia, tachypnea, diaphoresis, and pulse oximetry of 70% in room air. Lungs examination revealed the presence of rales in the left base. Chest radiography showed a diffuse and bilateral reticulo-nodular pattern. HIV serology was positive. Empirical antimicrobial therapy and corticosteroids were initiated. On the third day of hospitalization, petechiae appeared over the periumbilical area, but no further investigation was undertaken because the patient died soon after. The autopsy findings were compatible with S. stercoralis disseminated infection, a hepatic intestinal chronic form of schistosomiasis, and septic shock as the primary cause of death. The authors call attention to this infrequent association.

  17. Schistosoma mansoni Infections, Undernutrition and Anaemia among Primary Schoolchildren in Two Onshore Villages in Rorya District, North-Western Tanzania.

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    Munisi, David Zadock; Buza, Joram; Mpolya, Emmanuel A; Kinung'hi, Safari M

    2016-01-01

    Undernutrition and anaemia remains to be a major public health problem in many developing countries, where they mostly affect children. Intestinal parasitic infections are known to affect both growth and haemoglobin levels. Much has been reported on the impact of geohelminths on anaemia and undernutrition, leaving that of Schistosoma mansoni not well studied. Therefore this study intended to determine the association between S.mansoni infections, anaemia and undernutrition among schoolchildren in Rorya district, Northwestern Tanzania. A cross-sectional study was carried among schoolchildren in two onshore villages namely Busanga and Kibuyi in Rorya district. Single stool specimens were collected from 513 randomly selected schoolchildren and processed for microscopic examination using the Kato-Katz method. Nutritional status was determined by anthropometry. Blood samples were also collected and examined for malaria parasites and haemoglobin levels using the Giemsa stain and HaemoCue methods, respectively. A pretested questionnaire was used to collect socio-demographic data and associated factors. The prevalence of S. mansoni infection and malaria was 84.02% and 9.16%, respectively. Other parasites found were Ascaris lumbricoides (1.36%) and Hookworm (1.36%). The prevalence of stunting and wasting was 38.21% and 14.42%, respectively. The prevalence of anaemia was 29.43%, whereby 0.58% had severe anaemia. S. mansoni infection was not found to be associated with undernutrition or anaemia (p>0.05). The risk of stunting and wasting increased with increasing age (pAnaemia was associated with age, sex and village of residence (panaemia are highly prevalent in the study area. The observed rates of undernutrition and anaemia were seen not to be associated with S.mansoni infection suggesting possibly being a result of poor dietary nutrients. This study suggests that policy makers should consider Rorya district for inclusion into national schistosomiasis control and school

  18. Prevalence of intestinal helminth infection among school children in Maksegnit and Enfranz Towns, northwestern Ethiopia, with emphasis on Schistosoma mansoni infection.

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    Gashaw, Fikru; Aemero, Mulugeta; Legesse, Mengistu; Petros, Beyene; Teklehaimanot, Tilahun; Medhin, Girmay; Berhe, Nega; Mekonnen, Yalemtsehay; Erko, Berhanu

    2015-10-31

    Schistosomiasis is endemic in Ethiopia and previously unknown transmission foci have been reported from time to time in different parts of the country. Further surveys are required in areas where endemicity of the disease is not known to cover them with control program if transmission is taking place. This study, therefore, aims to assess the magnitude of schistosomiasis mansoni and soil-transmitted helminthiasis in Maksegnit and Enfranz Towns, northwestern Ethiopia. Cross-sectional parasitological and malacological surveys were conducted in three schools found in Maksegnit and Enfranz Towns. Stool specimens were collected from 550 randomly selected school children (age range 5 to 17 years) and processed for microscopic examination using Kato-Katz method (single smear per stool sample). Malacological survey was conducted in Gumara and Garno Rivers found in the study areas. Biomphalaria pfeifferi snails collected from the two rivers were individually exposed to artificial light in order to induce cercarial shedding. Laboratory-bred Swiss albino mice were exposed to the cercariae and definite identification of the schistosome species was made based on morphology. The overall prevalence of S. mansoni infection was found to be 49%; however, it varied by schools, with Selam having 60.7%, and Maksegnit Number 1 and 2 having 45.8 and 39.6%, respectively. The respective mean intensity of S. mansoni infection among school children in Selam, Maksegnit Number 1 and Maksegnit Number 2 Schools were 243, 194 and 183 eggs per gram of stool (epg). In all the study areas there was no difference in prevalence of S. mansoni infection in relation to age, however, the prevalence varied by sex, with males having highest prevalence (54.5% vs 44.1%) (p = 0.012). Adult S. mansoni worms were harvested from mice exposed to cercariae shed from B. pfeifferi on the 6(th) week post-exposure. The prevalence of Ascaris lumbricoides single infection was 16.5% while its co-infection with S

  19. Improvement of the liver pathology by the aqueous extract and the n-butanol fraction of Sida pilosa Retz in Schistosoma mansoni-infected mice.

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    Jatsa, Hermine Boukeng; Russo, Remo Castro; Pereira, Cintia Aparecida de Jesus; Aguilar, Edenil Costa; Garcia, Cristiana Couto; Araújo, Emília Souza; Oliveira, Jailza Lima Rodrigues; Rodrigues, Vanessa Fernandes; de Oliveira, Vinícius Gustavo; Alvarez-Leite, Jacqueline Isaura; Braga, Fernão Castro; Louis-Albert Tchuem Tchuente; Kamtchouing, Pierre; Negrão-Corrêa, Deborah Aparecida; Teixeira, Mauro Martins

    2016-03-02

    Sida pilosa Retz (Malvaceae) is a plant used in Africa for the treatment of intestinal helminthiasis, lower abdominal pains and dysmenorrhea. In order to determine the potential use of S. pilosa in the treatment of schistosomiasis mansoni, we evaluated the schistosomicidal, antioxidant and anti-fibrotic properties of the aqueous extract and the n-butanol fraction of its aerial parts. S. pilosa aqueous extract (SpAE) at 100, 200 and 400mg/kg and n-butanol fraction (SpBF) at 50, 100 and 200mg/kg were administered per os to Schistosoma mansoni-infected mice for 4 weeks. Praziquantel (100mg/kg × 5 days) was used as reference drug. After sacrifice, worm burden and egg count, transaminases and proteins levels were evaluated. Malondialdehyde (MDA), lipid hydroperoxydes (LOOH), catalase (CAT), superoxide dismutase (SOD), eosinophil peroxidase (EPO) and myeloperoxidase (MPO) were also measured. The anti-fibrotic effect of the plant was evaluated by the determination of hydroxyproline and γ-interferon (IFN-γ). The treatment of S. mansoni-infected mice by SpAE or SpBF resulted in a moderate reduction of worm burden and egg load in the liver and intestine. Both SpAE and SpBF significantly reversed the increasing liver proteins, MDA, LOOH and CAT levels induced by the infection. Moreover, SOD activity was improved by SpAE and SpBF. Schistosomiasis mansoni considerably increased the EPO (p<0.001) and MPO activities (p<0.001). SpAE treatment significantly reduced EPO and MPO activities at all doses. SpBF failed to reduce the increasing MPO and decreased EPO only at the highest dose. S. mansoni-infection induced an increase in hydroxyproline content (p<0.001) and a decrease in IFN-γ level (p<0.001). Both SpAE and SpBF significantly reduced hepatic hydroxyproline content, while only SpAE (p<0.05) improved IFN-γ level. These results suggest that the liver pathology in schistosomiasis mansoni is improved by S. pilosa aqueous extract, which disclosed a moderate schistosomicidal

  20. A case of vulval schistosomiasis

    African Journals Online (AJOL)

    the lesions on the left that may be lichen planus like, but not typical. The nodules. A case of vulval schistosomiasis. O'Mahony D, MBBCh, DCH, DTM&H, DPH, DIP MID COG (SA), FRCGP. Family Practitioner, Bridge Street, Port St Johns. Banach L, MD, PhD, MIAC. Associate Professor, Department of Pathology, Faculty of ...

  1. Schistosomiasis collection at NHM (SCAN

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    Emery Aidan M

    2012-09-01

    Full Text Available Abstract Background The Natural History Museum (NHM is developing a repository for schistosomiasis-related material, the Schistosomiasis Collection at NHM (SCAN as part of its existing Wolfson Wellcome Biomedical Laboratory (WWBL. This is timely because a major research and evaluation effort to understand control and move towards elimination of schistosomiasis in Africa has been initiated by the Schistosomiasis Consortium for Operational Research and Evaluation (SCORE, resulting in the collection of many important biological samples, including larval schistosomes and snails. SCAN will collaborate with a number of research groups and control teams and the repository will acquire samples relevant to both immediate and future research interest. The samples collected through ongoing research and field activities, WWBL’s existing collections, and other acquisitions will be maintained over the long term and made available to the global research community for approved research purposes. Goals include: · Consolidation of the existing NHM schistosome and snail collections and transfer of specimens into suitable long-term storage systems for DNA retrieval, · Long-term and stable storage of specimens collected as part of on going field programmes initially in Africa especially relating to the SCORE research programmes, · Provision of access to snail and schistosome collections for approved research activities.

  2. Targeted identification of Schistosoma mansoni egg glycans

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    Robijn, Marjolein Louise Maria

    2008-01-01

    Schistosomiasis, also known as bilharzia, is a disease that still occurs in many parts of Africa, the Middle East and Southern America, mainly Brasil and the Caribbean. Schistosomiasis is, after malaria, the second most common parasitic infection. Currently 200 million people are infected with the

  3. Biomphalaria species distribution and its effect on human Schistosoma mansoni infection in an irrigated area used for rice cultivation in northeast Brazil

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    Delmany Moitinho Barboza

    2012-09-01

    Full Text Available The role of irrigated areas for the spread of schistosomiasis is of worldwide concern. The aim of the present study was to investigate the spatial distribution of the intermediate snail host Biomphalaria in an area highly endemic for schistosomiasis due to Schistosoma mansoni, evaluating the relationship between irrigation and types of natural water sources on one hand, and the influence of place and time of water exposure on the intensity of human infection on the other. A geographical information system (GIS was used to map the distribution of the intermediate snail hosts in Ilha das Flores, Sergipe, Brazil, combined with a clinical/epidemiological survey. We observed a direct correlation between the intensity of human infection with S. mansoni and irrigation projects. Malacological studies to identify snail species and infection rates showed that B. glabrata is the main species responsible for human schistosomiasis in the municipality, but that B. straminea also plays a role. Our results provide evidence for a competitive selection between the two snail species in rice fields with a predominance of B. glabrata in irrigation systems and B. straminea in natural water sources.

  4. Efficacy of praziquantel and reinfection patterns in single and mixed infection foci for intestinal and urogenital schistosomiasis in Cameroon.

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    Tchuem Tchuenté, Louis-Albert; Momo, Sabine C; Stothard, J Russell; Rollinson, David

    2013-11-01

    The regular administration of the anthelminthic drug praziquantel (PZQ) to school-aged children (and other high-risk groups) is the cornerstone of schistosomiasis control. Whilst the performance of PZQ against single schistosome species infections is well-known, performance against mixed species infections is less so, as are patterns of re-infection following treatment. To address this, a study using a double treatment with PZQ, administered at 40 mg/kg spaced by 3 weeks, took place in two mixed intestinal-urogenital schistosomiasis foci in northern Cameroon (Bessoum and Ouro-Doukoudje) and in one single intestinal schistosomiasis infection focus (Makenene). A total of just under 1000 children were examined and the Schistosoma-infected children were re-examined at several parasitological follow-ups over a 1-year period posttreatment. Overall cure rates against Schistosoma spp. in the three settings were good, 83.3% (95% confidence interval (CI)=77.9-87.7%) in Bessoum, 89.0% (95% CI=79.1-94.6%) in Ouro Doukoudje, and 95.3% (95% CI=89.5-98.0%) in Makenene. Interestingly, no case of mixed schistosome infection was found after treatment. Cure rates for S. mansoni varied from 99.5% to 100%, while that for S. haematobium were considerably lower, varying from 82.7% to 88.0%. Across transmission settings, patterns of re-infection for each schistosome species were different such that generalizations across foci were difficult. For example, at the 6-month follow-up, re-infection rates were higher for S. haematobium than for S. mansoni with re-infection rates for S. haematobium varying from 9.5% to 66.7%, while for S. mansoni, lower rates were observed, ranging between nil and 24.5%. At the 12-month follow-up, re-infection rates varied from 9.1% to 66.7% for S. haematobium and from nil to 27.6% for S. mansoni. Alongside these parasitological studies, concurrent malacological surveys took place to monitor the presence of intermediate host snails of schistosomiasis. In the two

  5. Cross-species protection: Schistosoma mansoni Sm-p80 vaccine confers protection against Schistosoma haematobium in hamsters and baboons.

    Science.gov (United States)

    Karmakar, Souvik; Zhang, Weidong; Ahmad, Gul; Torben, Workineh; Alam, Mayeen U; Le, Loc; Damian, Raymond T; Wolf, Roman F; White, Gary L; Carey, David W; Carter, Darrick; Reed, Steven G; Siddiqui, Afzal A

    2014-03-05

    The ability of the Schistosoma mansoni antigen, Sm-p80, to provide cross-species protection against Schistosoma haematobium challenge was evaluated in hamster and baboon models. Pronounced reduction in worm burden (48%) and in tissue egg load (64%) was observed in hamsters vaccinated with recombinant Sm-p80 admixed with glucopyranosyl lipid adjuvant-stable emulsion (GLA-SE). Similarly, in baboons, the Sm-p80/GLA-SE vaccine produced a 25% reduction in S. haematobium adult worms and decreased the egg load in the urinary bladder by 64%. A 40% and 53% reduction in fecal and urine egg output, respectively, was observed in vaccinated baboons. A balanced pro-inflammatory (Th17 and Th1) and Th2 type of response was generated after vaccination and appears indicative of augmented prophylactic efficacy. These data on cross-species protection coupled with the prophylactic, therapeutic and antifecundity efficacy against the homologous parasite, S. mansoni, reinforces Sm-p80 as a promising vaccine candidate. It is currently being prepared for GMP-compliant manufacture and for further pre-clinical development leading to human clinical trials. These results solidify the expectation that the Sm-p80 vaccine will provide relief for both the intestinal and the urinary schistosomiasis and thus will be greatly beneficial in reducing the overall burden of schistosomiasis. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Spatial distribution of schistosomiasis and geohelminthiasis cases in the rural areas of Pernambuco, Brazil

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    Verônica Santos Barbosa

    2012-10-01

    Full Text Available INTRODUCTION: The prevalence and intensity of geohelminth infections and schistosomiasis remain high in the rural areas of Zona da Mata, Pernambuco (ZMP, Brazil, where these parasites still represent a significant public health problem. The present study aimed to spatially assess the occurrences of schistosomiasis and geohelminthiasis in the ZMP. METHODS: The ZMP has a population of 1,132,544 inhabitants, formed by 43 municipalities. An ecological study was conducted, using secondary data relating to positive human cases and parasite loads of schistosomiasis and positive human cases of geohelminthiasis that were worked up in Excel 2007. We used the coordinates of the municipal headquarters to represent the cities which served as the unit of analysis of this study. The Kernel estimator was used to spatially analyze the data and identify distribution patterns and case densities, with analysis done in ArcGIS software. RESULTS: Spatial analysis from the Kernel intensity estimator made it possible to construct density maps showing that the northern ZMP was the region with the greatest number of children infected with parasites and the populations most intensely infected by Schistosoma mansoni. In relation to geohelminths, there was higher spatial distribution of cases of Ascaris lumbricoides and Trichuris trichiura in the southern ZMP, and greater occurrence of hookworms in the northern/central ZMP. CONCLUSIONS: Despite several surveys and studies showing occurrences of schistosomiasis and geohelminthiasis in the ZMP, no preventive measures that are known to have been effective in decreasing these health hazards have yet been implemented in the endemic area.

  7. Expression, purification and characterization of two leucine aminopeptidases of the blood fluke, Schistosoma mansoni.

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    Maggioli, Gabriela; Rinaldi, Gabriel; Giaudrone, Ines; Berasain, Patricia; Tort, José F; Brindley, Paul J; Carmona, Carlos

    2018-01-01

    Schistosomiasis is a major neglected tropical disease (NTD) and considered the most important of the human helminthiases in terms of morbidity and mortality. Whereas treatment with praziquantel has been effective since the 1980s, the potential for the emergence of drug resistance has propelled the search for new interventions. Studies have revealed key roles of proteases in parasitic helminths during establishment of infection, tissue invasion, immune evasion, parasite feeding and development throughout the different developmental stages, pinpointing them as possible candidates. The leucine aminopeptidases (LAPs), members of the M17 family of Zn-metalloproteases, preferentially cleave leucine (Leu) residues at the N-terminal end of proteins and short peptides. These enzymes display broad proteolytic activities beyond Leu hydrolysis and are involved in processing, maturation, activation and/or degradation of substrates. As a vaccine immunogen, LAP induces protection against infection with the liver fluke Fasciola hepatica. Herein, two LAPs, SmLAP1 (Smp_030000) and SmLAP2 (Smp_083870) of the human blood fluke Schistosoma mansoni were cloned, expressed, purified and biochemically characterized. The enzymes differed in activity against diagnostic substrates, including leucine, methionine and arginine, with an optimal pH of 8.0. The activity increased in the presence of Mg+2 and Mn+2, and was inhibited by bestatin, a specific inhibitor of aminopeptidase. In addition, 1,10-phenanthroline and EDTA inhibited the enzymatic activity of SmLAP2. Finally, immunolocalization using antibodies specific for SmLAP1 and SmLAP2 identified the expression of these proteases in the egg and adult developmental stages of S. mansoni, and in intestinal epithelia, vitelline cells and sub-tegumental regions of the parasite. Characterization of schistosome proteases not only enhances understanding of the biology of schistosomes and schistosomiasis, but may also provide novel intervention

  8. A meta-analysis of experimental studies of attenuated Schistosoma mansoni vaccines in the mouse model

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    Mizuho eFukushige

    2015-02-01

    Full Text Available Schistosomiasis is a water-borne, parasitic disease of major public health importance. There has been considerable effort for several decades towards the development of a vaccine against the disease. Numerous mouse experimental studies using attenuated Schistosoma mansoni parasites for vaccination have been published since the 1960s. However, to date, there has been no systematic review or meta-analysis of these data. The aim of this study is to identify measurable experimental conditions that affect the level of protection against re-infection with S. mansoni in mice vaccinated with radiation attenuated cercariae. Following a systematic review, a total of 755 observations were extracted from 105 articles (published 1963-2007 meeting the searching criteria. Random effects meta-regression models were used to identify the influential predictors.Three predictors were found to have statistically significant effects on the level of protection from vaccination: increasing numbers of immunizing parasites had a positive effect on fraction of protection whereas increasing radiation dose and time to challenge infection had negative effects. Models showed that the irradiated cercariae vaccine has the potential to achieve protection as high as 78% with a single dose vaccination. This declines slowly over time but remains high for at least 8 months after the last immunization. These findings provide insights into the optimal delivery of attenuated parasite vaccination and into the nature and development of protective vaccine induced immunity against schistosomiasis which may inform the formulation of human vaccines and the predicted duration of protection and thus frequency of booster vaccines.

  9. HIV-1 Integrates Widely throughout the Genome of the Human Blood Fluke Schistosoma mansoni.

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    Sutas Suttiprapa

    2016-10-01

    Full Text Available Schistosomiasis is the most important helminthic disease of humanity in terms of morbidity and mortality. Facile manipulation of schistosomes using lentiviruses would enable advances in functional genomics in these and related neglected tropical diseases pathogens including tapeworms, and including their non-dividing cells. Such approaches have hitherto been unavailable. Blood stream forms of the human blood fluke, Schistosoma mansoni, the causative agent of the hepatointestinal schistosomiasis, were infected with the human HIV-1 isolate NL4-3 pseudotyped with vesicular stomatitis virus glycoprotein. The appearance of strong stop and positive strand cDNAs indicated that virions fused to schistosome cells, the nucleocapsid internalized and the RNA genome reverse transcribed. Anchored PCR analysis, sequencing HIV-1-specific anchored Illumina libraries and Whole Genome Sequencing (WGS of schistosomes confirmed chromosomal integration; >8,000 integrations were mapped, distributed throughout the eight pairs of chromosomes including the sex chromosomes. The rate of integrations in the genome exceeded five per 1,000 kb and HIV-1 integrated into protein-encoding loci and elsewhere with integration bias dissimilar to that of human T cells. We estimated ~ 2,100 integrations per schistosomulum based on WGS, i.e. about two or three events per cell, comparable to integration rates in human cells. Accomplishment in schistosomes of post-entry processes essential for HIV-1replication, including integrase-catalyzed integration, was remarkable given the phylogenetic distance between schistosomes and primates, the natural hosts of the genus Lentivirus. These enigmatic findings revealed that HIV-1 was active within cells of S. mansoni, and provided the first demonstration that HIV-1 can integrate into the genome of an invertebrate.

  10. Satellite climatology and the environmental risk of Schistosoma mansoni in Ethiopia and east Africa.

    Science.gov (United States)

    Malone, J B; Yilma, J M; McCarroll, J C; Erko, B; Mukaratirwa, S; Zhou, X

    2001-04-27

    Annual and seasonal composite maps prepared from the normalized difference vegetation index (NDVI) and earth surface maximum temperature (T(max)) satellite data from the archives of the Global land 1-km program of the United States Geological Survey (USGS) were studied for. their potential value, using geographic information system (GIS) methods, as surrogates of climate data in the development of environmental risk models for schistosomiasis in Ethiopia. Annual, wet season and dry season models were developed and iteratively analyzed for relationships with Schistosoma mansoni distribution and infection prevalence rates. Model-predicted endemic area overlays that best fit the distribution of sites with over 5% prevalence corresponded to values of NDVI 125-145 and T(max) 20-33 degrees C in the annual composite map, NDVI 125-145 and T(max) 18-29 degrees C for the wet season map, and NDVI 125-140 and T(max) 22-37 degrees C for the dry season map. The model-predicted endemic area was similar to that of a prior model developed using an independent agroecologic zone data set from the United Nations Food and Agriculture Organization (FAO). Results were consistent with field and laboratory data on the preferences and limits of tolerance of the S. mansoni-Biomphalaria pfeifferi system. Results suggest that Global 1-km NDVI and T(max), when used together, can be used as surrogate climate data for development of GIS risk assessment models for schistosomiasis. The model developed for Ethiopia based on global 1-km satellite data was extrapolated to a broader area of East Africa. When used with FAO agroecologic zone climate data limits of Africa extrapolation area.

  11. Evaluation of urine CCA assays for detection of Schistosoma mansoni infection in Western Kenya.

    Science.gov (United States)

    Shane, Hillary L; Verani, Jennifer R; Abudho, Bernard; Montgomery, Susan P; Blackstock, Anna J; Mwinzi, Pauline N M; Butler, Sara E; Karanja, Diana M S; Secor, W Evan

    2011-01-25

    Although accurate assessment of the prevalence of Schistosoma mansoni is important for the design and evaluation of control programs, the most widely used tools for diagnosis are limited by suboptimal sensitivity, slow turn-around-time, or inability to distinguish current from former infections. Recently, two tests that detect circulating cathodic antigen (CCA) in urine of patients with schistosomiasis became commercially available. As part of a larger study on schistosomiasis prevalence in young children, we evaluated the performance and diagnostic accuracy of these tests--the carbon test strip designed for use in the laboratory and the cassette format test intended for field use. In comparison to 6 Kato-Katz exams, the carbon and cassette CCA tests had sensitivities of 88.4% and 94.2% and specificities of 70.9% and 59.4%, respectively. However, because of the known limitations of the Kato-Katz assay, we also utilized latent class analysis (LCA) incorporating the CCA, Kato-Katz, and schistosome-specific antibody results to determine their sensitivities and specificities. The laboratory-based CCA test had a sensitivity of 91.7% and a specificity of 89.4% by LCA while the cassette test had a sensitivity of 96.3% and a specificity of 74.7%. The intensity of the reaction in both urine CCA tests reflected stool egg burden and their performance was not affected by the presence of soil transmitted helminth infections. Our results suggest that urine-based assays for CCA may be valuable in screening for S. mansoni infections.

  12. The Schistosoma mansoni Cytochrome P450 (CYP3050A1 Is Essential for Worm Survival and Egg Development.

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    Peter D Ziniel

    2015-12-01

    Full Text Available Schistosomiasis affects millions of people in developing countries and is responsible for more than 200,000 deaths annually. Because of toxicity and limited spectrum of activity of alternatives, there is effectively only one drug, praziquantel, available for its treatment. Recent data suggest that drug resistance could soon be a problem. There is therefore the need to identify new drug targets and develop drugs for the treatment of schistosomiasis. Analysis of the Schistosoma mansoni genome sequence for proteins involved in detoxification processes found that it encodes a single cytochrome P450 (CYP450 gene. Here we report that the 1452 bp open reading frame has a characteristic heme-binding region in its catalytic domain with a conserved heme ligating cysteine, a hydrophobic leader sequence present as the membrane interacting region, and overall structural conservation. The highest sequence identity to human CYP450s is 22%. Double stranded RNA (dsRNA silencing of S. mansoni (SmCYP450 in schistosomula results in worm death. Treating larval or adult worms with antifungal azole CYP450 inhibitors results in worm death at low micromolar concentrations. In addition, combinations of SmCYP450-specific dsRNA and miconazole show additive schistosomicidal effects supporting the hypothesis that SmCYP450 is the target of miconazole. Treatment of developing S. mansoni eggs with miconazole results in a dose dependent arrest in embryonic development. Our results indicate that SmCYP450 is essential for worm survival and egg development and validates it as a novel drug target. Preliminary structure-activity relationship suggests that the 1-(2,4-dichlorophenyl-2-(1H-imidazol-1-ylethan-1-ol moiety of miconazole is necessary for activity and that miconazole activity and selectivity could be improved by rational drug design.

  13. Monocyte Subsets in Schistosomiasis Patients with Periportal Fibrosis

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    Jamille Souza Fernandes

    2014-01-01

    Full Text Available A major issue with Schistosoma mansoni infection is the development of periportal fibrosis, which is predominantly caused by the host immune response to egg antigens. Experimental studies have pointed to the participation of monocytes in the pathogenesis of liver fibrosis. The aim of this study was to characterize the subsets of monocytes in individuals with different degrees of periportal fibrosis secondary to schistosomiasis. Monocytes were classified into classical (CD14++CD16−, intermediate (CD14++CD16+, and nonclassical (CD14+CD16++. The expressions of monocyte markers and cytokines were assessed using flow cytometry. The frequency of classical monocytes was higher than the other subsets. The expression of HLA-DR, IL-6, TNF-α, and TGF-β was higher in monocytes from individuals with moderate to severe fibrosis as compared to other groups. Although no differences were observed in receptors expression (IL-4R and IL-10R between groups of patients, the expression of IL-12 was lower in monocytes from individuals with moderate to severe fibrosis, suggesting a protective role of this cytokine in the development of fibrosis. Our data support the hypothesis that the three different monocyte populations participate in the immunopathogenesis of periportal fibrosis, since they express high levels of proinflammatory and profibrotic cytokines and low levels of regulatory markers.

  14. Effects of proteasome inhibitor MG-132 on the parasite Schistosoma mansoni

    Science.gov (United States)

    de Paula, Renato G.; Ornelas, Alice M. M.; Moreira, Érika B. C.; Badoco, Fernanda Rafacho; Magalhães, Lizandra G.; Verjovski-Almeida, Sergio; Rodrigues, Vanderlei

    2017-01-01

    inhibitor genes, IAP1 and BRE1, and in contrast, down-regulation of Apaf-1 apoptotic activator, thus suggesting that apoptosis is deregulated in S. mansoni exposed to MG-132. A considerable insight has been gained concerning the potential of MG-132 as a gene expression modulator, and overall the data suggest that the proteasome might be an important molecular target for the design of new drugs against schistosomiasis. PMID:28898250

  15. Analysis of Schistosoma mansoni genes shared with Deuterostomia and with possible roles in host interactions

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    Verjovski-Almeida Sergio

    2007-11-01

    Full Text Available Abstract Background: Schistosoma mansoni is a blood helminth parasite that causes schistosomiasis, a disease that affects 200 million people in the world. Many orthologs of known mammalian genes have been discovered in this parasite and evidence is accumulating that some of these genes encode proteins linked to signaling pathways in the parasite that appear to be involved with growth or development, suggesting a complex co-evolutionary process. Results: In this work we found 427 genes conserved in the Deuterostomia group that have orthologs in S. mansoni and no members in any nematodes and insects so far sequenced. Among these genes we have identified Insulin Induced Gene (INSIG, Interferon Regulatory Factor (IRF and vasohibin orthologs, known to be involved in mammals in mevalonate metabolism, immune response and angiogenesis control, respectively. We have chosen these three genes for a more detailed characterization, which included extension of their cloned messages to obtain full-length sequences. Interestingly, SmINSIG showed a 10-fold higher expression in adult females as opposed to males, in accordance with its possible role in regulating egg production. SmIRF has a DNA binding domain, a tryptophan-rich N-terminal region and several predicted phosphorylation sites, usually important for IRF activity. Fourteen different alternatively spliced forms of the S. mansoni vasohibin (SmVASL gene were detected that encode seven different protein isoforms including one with a complete C-terminal end, and other isoforms with shorter C-terminal portions. Using S. mansoni homologs, we have employed a parsimonious rationale to compute the total gene losses/gains in nematodes, arthropods and deuterostomes under either the Coelomata or the Ecdysozoa evolutionary hypotheses; our results show a lower losses/gains number under the latter hypothesis. Conclusion: The genes discussed which are conserved between S. mansoni and deuterostomes, probably have an

  16. The Schistosoma mansoni phylome: using evolutionary genomics to gain insight into a parasite’s biology

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    Silva Larissa

    2012-11-01

    Full Text Available Abstract Background Schistosoma mansoni is one of the causative agents of schistosomiasis, a neglected tropical disease that affects about 237 million people worldwide. Despite recent efforts, we still lack a general understanding of the relevant host-parasite interactions, and the possible treatments are limited by the emergence of resistant strains and the absence of a vaccine. The S. mansoni genome was completely sequenced and still under continuous annotation. Nevertheless, more than 45% of the encoded proteins remain without experimental characterization or even functional prediction. To improve our knowledge regarding the biology of this parasite, we conducted a proteome-wide evolutionary analysis to provide a broad view of the S. mansoni’s proteome evolution and to improve its functional annotation. Results Using a phylogenomic approach, we reconstructed the S. mansoni phylome, which comprises the evolutionary histories of all parasite proteins and their homologs across 12 other organisms. The analysis of a total of 7,964 phylogenies allowed a deeper understanding of genomic complexity and evolutionary adaptations to a parasitic lifestyle. In particular, the identification of lineage-specific gene duplications pointed to the diversification of several protein families that are relevant for host-parasite interaction, including proteases, tetraspanins, fucosyltransferases, venom allergen-like proteins, and tegumental-allergen-like proteins. In addition to the evolutionary knowledge, the phylome data enabled us to automatically re-annotate 3,451 proteins through a phylogenetic-based approach rather than solely sequence similarity searches. To allow further exploitation of this valuable data, all information has been made available at PhylomeDB (http://www.phylomedb.org. Conclusions In this study, we used an evolutionary approach to assess S. mansoni parasite biology, improve genome/proteome functional annotation, and provide insights into

  17. Effects of proteasome inhibitor MG-132 on the parasite Schistosoma mansoni.

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    Enyara R Morais

    apoptosis inhibitor genes, IAP1 and BRE1, and in contrast, down-regulation of Apaf-1 apoptotic activator, thus suggesting that apoptosis is deregulated in S. mansoni exposed to MG-132. A considerable insight has been gained concerning the potential of MG-132 as a gene expression modulator, and overall the data suggest that the proteasome might be an important molecular target for the design of new drugs against schistosomiasis.

  18. Estudo piloto sobre esquistossomose mansoni em área rural do Município de Itanhomi, Vale do Rio Doce, Minas Gerais

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    Maria José Conceição

    1978-12-01

    Full Text Available Neste trabalho os autores apresentam dados relativos à prevalência e formas clinicas da esquistossomose mansoni, hospedeiro intermediário e determinação do seu índice de infecção em Santa Luzia do Carneiro, área rural do Município de Itanhomi, Vale do Rio Doce, Minas Gerais. O estudo seccional da população revelou 42,1% de positividade para ovos de S.mansoni em um exame de fezes peto método de Lutz (Hoffmann, Ponz, Janer e um percentual de 6,8% de pacientes com hepato-esplenomegalia. O hospedeiro intermediário encontrado foi a B.glabrata com um índice de infecção de 3,2%.Data on prevalence and morbidity of Schistosomiasis mansoni, local intermediate host and its rate of infection, in the county of Santa Luzia do Carneiro, State of Minas Gerais, Brazil, are presented. A cross-seccionai study demonstrated a figure of 42.1 per cent of positivity for S.mansoni eggs in one faeces parasitoiogic examination by Lutz method (Hoffman, Pons, Janer metod. Liver and spleen eniagement were observed in 6.8 per cent of the patients. The intermediate host B.glabrata showed an infection rate of 3.2per cent.

  19. Evaluation of urine-circulating cathodic antigen (Urine-CCA) cassette test for the detection of Schistosoma mansoni infection in areas of moderate prevalence in Ethiopia.

    Science.gov (United States)

    Erko, Berhanu; Medhin, Girmay; Teklehaymanot, Tilahun; Degarege, Abraham; Legesse, Mengistu

    2013-08-01

    To evaluate the diagnostic performance of antigen detecting urine-CCA cassette test for the detection of Schistosoma mansoni infection in areas of moderate prevalence in Ethiopia. Stool specimens were collected from 620 schoolchildren on three consecutive days. The samples were microscopically examined using double Kato slides; midstream urine specimens were also collected for three consecutive days and tested for S. mansoni. The sensitivity of the urine-CCA cassette test was determined using combined results of six Kato-Katz thick smears and three urine-CCA cassette tests as gold standard. The specificity of the urine-CCA cassette test was evaluated in an area where schistosomiasis is not endemic. Prevalence of S. mansoni infection as determined by single urine-CCA cassette test was 65.9%, by single Kato-Katz smear 37.3% and by six Kato-Katz thick smears 53.1% (P CCA cassette test was significantly (P CCA cassette test showed 100% specificity in endemic settings. In moderate and high prevalence areas, urine-CCA cassette test is more sensitive than the Kato-Katz method and can be used for screening and mapping of S. mansoni infection. © 2013 Blackwell Publishing Ltd.

  20. schistosomiasis presenting as acute appendicitis

    African Journals Online (AJOL)

    Damary

    2006-10-10

    Oct 10, 2006 ... Revista Do Institution De Medicina Tropical de Sao Paulo. 1962; 8: 167-172. 5. Jones H.J.S., Ibrahim A.E.K. and Deroda J.K.. Schistosomiasis of the appendix in the UK. Brit. J. Clin. Pract. 1997; 51: 183. 6. Lee J.FY., Chung C.C. and Lau W.Y. A case of schistosomal appendicitis. IJCP 1997; 51: 518-519. 7.

  1. Synergistic effects of in vitro combinations of piplartine, epiisopiloturine and praziquantel against Schistosoma mansoni.

    Science.gov (United States)

    Campelo, Yuri Dias Macedo; Mafud, Ana Carolina; Véras, Leiz Maria Costa; Guimarães, Maria Adelaide; Yamaguchi, Lydia F; Lima, David Fernandes; Arcanjo, Daniel Dias Rufino; Kato, Massuo J; Mendonça, Ronaldo Z; Pinto, Pedro Luiz Silva; Mascarenhas, Yvonne Primerano; Silva, Marcos P N; de Moraes, Josué; Eaton, Peter; de Souza de Almeida Leite, José Roberto

    2017-04-01

    Schistosomiasis is a world health problem, and praziquantel is the only drug currently used for the treatment. There is some evidence that extensive monotherapy of praziquantel may be leading to drug resistance in the parasite. In order to find alternative treatments, the effects of the combination of epiisopiloturine (EPI), piplartine (PPT) and praziquantel (PZQ) were evaluated. Similarity analysis of these compounds was performed using optimized molecular structures to compare the shape and the charge modeling of combinations between PZQ and EPI or PPT. Supported by this data, in vitro association of PZQ-PPT, PZQ-EPI, and EPI-PPT was carried out, and the activity of these combinations against Schistosoma mansoni was assessed. The results showed synergistic activity with a combination index (CI) of 0.42 for the treatment with PZQ-PPT. Both PZQ-EPI and EPI-PPT combinations also showed synergistic effects, with CI values of 0.86 and 0.61, respectively. Surface alterations in the tegument of adult schistosomes after the treatments were observed using laser confocal microscopy and scanning electron microscopy. Additionally, the association of EPI-PPT decreased the cytotoxicity when compared with both isolated compounds in three different lines of mammalian cells. Thus, synergistic combinations of PZQ-PPT, PZQ-EPI, and EPI-PPT create the possibility of reduced doses to be used against Schistosoma mansoni. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  2. Two sequential PCR amplifications for detection of Schistosoma mansoni in stool samples with low parasite load

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    Maria Cristina Carvalho do Espírito-Santo

    2012-10-01

    Full Text Available Schistosomiasis constitutes a major public health problem, with an estimated 200 million individuals infected worldwide and 700 million people living in risk areas. In Brazil there are areas of high, medium and low endemicity. Studies have shown that in endemic areas with a low prevalence of Schistosoma infection the sensitivity of parasitological methods is clearly reduced. Consequently diagnosis is often impeded due to the presence of false-negative results. The aim of this study is to present the PCR reamplification (Re-PCR protocol for the detection of Schistosoma mansoni in samples with low parasite load (with less than 100 eggs per gram (epg of feces. Three methods were used for the lysis of the envelopes of the S. mansoni eggs and two techniques of DNA extraction were carried out. Extracted DNA was quantified, and the results suggested that the extraction technique, which mixed glass beads with a guanidine isothiocyanate/phenol/chloroform (GT solution, produced good results. PCR reamplification was conducted and detection sensitivity was found to be five eggs per 500 mg of artificially marked feces. The results achieved using these methods suggest that they are potentially viable for the detection of Schistosoma infection with low parasite load.

  3. Two sequential PCR amplifications for detection of Schistosoma mansoni in stool samples with low parasite load.

    Science.gov (United States)

    Espírito-Santo, Maria Cristina Carvalho do; Alvarado-Mora, Mónica Viviana; Pinto, Pedro Luiz Silva; Carrilho, Flair José; Pinho, João Renato Rebello; Gryschek, Ronaldo Cesar Borges

    2012-01-01

    Schistosomiasis constitutes a major public health problem, with an estimated 200 million individuals infected worldwide and 700 million people living in risk areas. In Brazil there are areas of high, medium and low endemicity. Studies have shown that in endemic areas with a low prevalence of Schistosoma infection the sensitivity of parasitological methods is clearly reduced. Consequently diagnosis is often impeded due to the presence of false-negative results. The aim of this study is to present the PCR reamplification (Re-PCR) protocol for the detection of Schistosoma mansoni in samples with low parasite load (with less than 100 eggs per gram (epg) of feces). Three methods were used for the lysis of the envelopes of the S. mansoni eggs and two techniques of DNA extraction were carried out. Extracted DNA was quantified, and the results suggested that the extraction technique, which mixed glass beads with a guanidine isothiocyanate/phenol/chloroform (GT) solution, produced good results. PCR reamplification was conducted and detection sensitivity was found to be five eggs per 500 mg of artificially marked feces. The results achieved using these methods suggest that they are potentially viable for the detection of Schistosoma infection with low parasite load.

  4. Schistosoma mansoni: parasitology and immunology of baboons vaccinated with irradiated cryopreserved schistosomula

    Energy Technology Data Exchange (ETDEWEB)

    Damian, R.T.; Powell, M.R.; Roberts, M.L. (Georgia Univ., Athens (USA). Dept. of Zoology); Clark, J.D. (Georgia Univ., Athens (USA). Lab. Animal Medicine); Stirewalt, M.A.; Lewis, F.A. (Biomedical Research Inst., Rockville, MD (USA))

    1985-06-01

    Young baboons (Papio cynocephalus) were vaccinated with ..gamma..-irradiated (500 Gy) cryopreserved Puerto Rican strain schistosomula of S. mansoni. Protection against heterologous, normal Kenyan Strain S. mansoni challenge infection was erratic and partial; and two putative correlates of immunity, reduced worm fecundity and change in worm location (anterior shift) were not observed. However, immunization of baboons with this vaccine resulted in a stimulated immune system. Both cellular and humoral anamnesis were demonstrable in vaccinated-challenged baboons. Schistosome infection-associated IgM hypergammaglobulinemia was also greatly reduced in vaccinated-challenged baboons. However IgG antibodies to adult, egg, and cercarial antigens were increased after challenge infection in preimmunized baboons. Vaccination appears to have resulted in a redirection of the immune system into anti-parasite channels, but this more specific immune response was insufficient to confer good protection against challenge infection in this experiment. The dampening effect of the vaccine on the hypergammaglobulinemia of schistosomiasis is another candidate for a possible ''anti-pathogenesis'' effect of irradiated schistosome larval vaccines.

  5. Treatment of acute experimental schistosomiasis Tratamento da esquistossomose aguda experimental

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    Zilton A. Andrade

    1989-12-01

    Full Text Available A model of acute schistosomiasis of the mouse was used to observe whether curative treatment would be followed by an enhancement of the hepatic and splenic lesions, as a consequence of the massive destruction of worms and eggs within the portal system. Mice infected with 50 cercariae of Schistosoma mansoni were treated with both oxamniquine and praziquantel on the 50th day of infection and submitted to a sequential histologic examination from the 2nd to the 45th day after treatment. Although severe focal lesions due to dead and disintegranting worms were present in the livers of the treated animals, no aggravation of the general changes (reative hepatitis and splenitis, or periovular granulomas was seen in comparison with a control non-treated group. Of 50 animals treated during the acute phase of schistosomiasis only one died espontaneously, while 16 ou of 30 infected controls died before the end of the experiment. The present investigation indicates that curative treatment during the acute phase of schistosomiasis does not enhance previous lesions at first and results in progressive disappearance of the lesions starting six days following chemotherapy.Foi utilizado um modelo de esquistossomose aguda do camundongo para testar se o tratamentop curativo da parasitose nesta fase poderia produzir uma exacerbação das lesões hepáticas e esplênicas, em virtude da destruição maciça de vermes e ovos nointerior do sistema porta. Camundongos infectados com 50 cercárias do Schistosoma mansoni foram tratados no 50º dia da infecção por uma combinação de oxamniquine e praziquantel e submetidos a exames histopatológicos seqüenciados desde o 2º até o 45º dia após o tratamento. Muito embora tenham sido encontrados lesões focais intensas causadas por vermes mortos no interior do fígado, não foi encontrada qualquer evidência de agravamento das lesões gerais (hepatite reacional e esplenite, ou nos granulomas periovulares quando se fez

  6. Geostatistical model-based estimates of Schistosomiasis prevalence among individuals aged ≤ 20 years in West Africa.

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    Nadine Schur

    2011-06-01

    Full Text Available BACKGROUND: Schistosomiasis is a water-based disease that is believed to affect over 200 million people with an estimated 97% of the infections concentrated in Africa. However, these statistics are largely based on population re-adjusted data originally published by Utroska and colleagues more than 20 years ago. Hence, these estimates are outdated due to large-scale preventive chemotherapy programs, improved sanitation, water resources development and management, among other reasons. For planning, coordination, and evaluation of control activities, it is essential to possess reliable schistosomiasis prevalence maps. METHODOLOGY: We analyzed survey data compiled on a newly established open-access global neglected tropical diseases database (i to create smooth empirical prevalence maps for Schistosoma mansoni and S. haematobium for individuals aged ≤ 20 years in West Africa, including Cameroon, and (ii to derive country-specific prevalence estimates. We used Bayesian geostatistical models based on environmental predictors to take into account potential clustering due to common spatially structured exposures. Prediction at unobserved locations was facilitated by joint kriging. PRINCIPAL FINDINGS: Our models revealed that 50.8 million individuals aged ≤ 20 years in West Africa are infected with either S. mansoni, or S. haematobium, or both species concurrently. The country prevalence estimates ranged between 0.5% (The Gambia and 37.1% (Liberia for S. mansoni, and between 17.6% (The Gambia and 51.6% (Sierra Leone for S. haematobium. We observed that the combined prevalence for both schistosome species is two-fold lower in Gambia than previously reported, while we found an almost two-fold higher estimate for Liberia (58.3% than reported before (30.0%. Our predictions are likely to overestimate overall country prevalence, since modeling was based on children and adolescents up to the age of 20 years who are at highest risk of infection. CONCLUSION

  7. Geostatistical model-based estimates of Schistosomiasis prevalence among individuals aged ≤ 20 years in West Africa.

    Science.gov (United States)

    Schur, Nadine; Hürlimann, Eveline; Garba, Amadou; Traoré, Mamadou S; Ndir, Omar; Ratard, Raoult C; Tchuem Tchuenté, Louis-Albert; Kristensen, Thomas K; Utzinger, Jürg; Vounatsou, Penelope

    2011-06-01

    Schistosomiasis is a water-based disease that is believed to affect over 200 million people with an estimated 97% of the infections concentrated in Africa. However, these statistics are largely based on population re-adjusted data originally published by Utroska and colleagues more than 20 years ago. Hence, these estimates are outdated due to large-scale preventive chemotherapy programs, improved sanitation, water resources development and management, among other reasons. For planning, coordination, and evaluation of control activities, it is essential to possess reliable schistosomiasis prevalence maps. We analyzed survey data compiled on a newly established open-access global neglected tropical diseases database (i) to create smooth empirical prevalence maps for Schistosoma mansoni and S. haematobium for individuals aged ≤ 20 years in West Africa, including Cameroon, and (ii) to derive country-specific prevalence estimates. We used Bayesian geostatistical models based on environmental predictors to take into account potential clustering due to common spatially structured exposures. Prediction at unobserved locations was facilitated by joint kriging. Our models revealed that 50.8 million individuals aged ≤ 20 years in West Africa are infected with either S. mansoni, or S. haematobium, or both species concurrently. The country prevalence estimates ranged between 0.5% (The Gambia) and 37.1% (Liberia) for S. mansoni, and between 17.6% (The Gambia) and 51.6% (Sierra Leone) for S. haematobium. We observed that the combined prevalence for both schistosome species is two-fold lower in Gambia than previously reported, while we found an almost two-fold higher estimate for Liberia (58.3%) than reported before (30.0%). Our predictions are likely to overestimate overall country prevalence, since modeling was based on children and adolescents up to the age of 20 years who are at highest risk of infection. We present the first empirical estimates for S. mansoni and S

  8. Schistosoma mansoni Infection of Mice, Rats and Humans Elicits a Strong Antibody Response to a Limited Number of Reduction-Sensitive Epitopes on Five Major Tegumental Membrane Proteins.

    Science.gov (United States)

    Krautz-Peterson, Greice; Debatis, Michelle; Tremblay, Jacqueline M; Oliveira, Sergio C; Da'dara, Akram A; Skelly, Patrick J; Shoemaker, Charles B

    2017-01-01

    Schistosomiasis is a major disease of the developing world for which no vaccine has been successfully commercialized. While numerous Schistosoma mansoni worm antigens have been identified that elicit antibody responses during natural infections, little is known as to the identities of the schistosome antigens that are most prominently recognized by antibodies generated through natural infection. Non-reducing western blots probed with serum from schistosome-infected mice, rats and humans on total extracts of larval or adult schistosomes revealed that a small number of antigen bands predominate in all cases. Recognition of each of these major bands was lost when the blots were run under reducing condition. We expressed a rationally selected group of schistosome tegumental membrane antigens in insect host cells, and used the membrane extracts of these cells to unambiguously identify the major antigens recognized by S. mansoni infected mouse, rat and human serum. These results revealed that a limited number of dominant, reduction-sensitive conformational epitopes on five major tegumental surface membrane proteins: SmTsp2, Sm23, Sm29, SmLy6B and SmLy6F, are primary targets of mouse, rat and human S. mansoni infection sera antibodies. We conclude that, Schistosoma mansoni infection of both permissive (mouse) and non-permissive (rat) rodent models, as well as humans, elicit a dominant antibody response recognizing a limited number of conformational epitopes on the same five tegumental membrane proteins. Thus it appears that neither infecting schistosomula nor mature adult schistosomes are substantively impacted by the robust circulating anti-tegumental antibody response they elicit to these antigens. Importantly, our data suggest a need to re-evaluate host immune responses to many schistosome antigens and has important implications regarding schistosome immune evasion mechanisms and schistosomiasis vaccine development.

  9. Schistosoma mansoni Infection of Mice, Rats and Humans Elicits a Strong Antibody Response to a Limited Number of Reduction-Sensitive Epitopes on Five Major Tegumental Membrane Proteins.

    Directory of Open Access Journals (Sweden)

    Greice Krautz-Peterson

    2017-01-01

    Full Text Available Schistosomiasis is a major disease of the developing world for which no vaccine has been successfully commercialized. While numerous Schistosoma mansoni worm antigens have been identified that elicit antibody responses during natural infections, little is known as to the identities of the schistosome antigens that are most prominently recognized by antibodies generated through natural infection. Non-reducing western blots probed with serum from schistosome-infected mice, rats and humans on total extracts of larval or adult schistosomes revealed that a small number of antigen bands predominate in all cases. Recognition of each of these major bands was lost when the blots were run under reducing condition. We expressed a rationally selected group of schistosome tegumental membrane antigens in insect host cells, and used the membrane extracts of these cells to unambiguously identify the major antigens recognized by S. mansoni infected mouse, rat and human serum. These results revealed that a limited number of dominant, reduction-sensitive conformational epitopes on five major tegumental surface membrane proteins: SmTsp2, Sm23, Sm29, SmLy6B and SmLy6F, are primary targets of mouse, rat and human S. mansoni infection sera antibodies. We conclude that, Schistosoma mansoni infection of both permissive (mouse and non-permissive (rat rodent models, as well as humans, elicit a dominant antibody response recognizing a limited number of conformational epitopes on the same five tegumental membrane proteins. Thus it appears that neither infecting schistosomula nor mature adult schistosomes are substantively impacted by the robust circulating anti-tegumental antibody response they elicit to these antigens. Importantly, our data suggest a need to re-evaluate host immune responses to many schistosome antigens and has important implications regarding schistosome immune evasion mechanisms and schistosomiasis vaccine development.

  10. Evaluation of serum levels of IL-9 and IL-17 in human Schistosoma mansoni infection and their relationship with periportal fibrosis.

    Science.gov (United States)

    Barreto, Ana Virgínia Matos Sá; Lacerda, Glaucia Alyne Nunes de; Figueiredo, Anna Lígia de Castro; Diniz, George Tadeu Nunes; Gomes, Elainne Christine Souza; Domingues, Ana Lúcia Coutinho; Barbosa, Constança Simões; Montengro, Silvia Maria Lucena; Morais, Clarice Neuenschwander Lins de

    2016-12-01

    Serum levels of IL-9 and IL-17 cytokines were evaluated in patients in the acute, chronic phases and clinical forms of human schistosomiasis and in different classifications of periportal fibrosis. No significant differences between the groups of the disease with serum levels of cytokine were found. However, this study discusses the results of some cytokines that have not fully defined roles in the pathology of human schistosomiasis. Furthermore, an examination was made of subjects in the acute phase. This is an important group that is difficult to identify in areas where the disease is endemic. More studies are being undertaken to study the role of IL-9 and IL-17 in human Schistosoma mansoni infection and their relationship with the immunopathogenesis of disease. Copyright © 2016 Elsevier GmbH. All rights reserved.

  11. The Role of Efflux Pumps in Schistosoma mansoni Praziquantel Resistant Phenotype

    Science.gov (United States)

    Armada, Ana; Belo, Silvana; Carrilho, Emanuel; Viveiros, Miguel; Afonso, Ana

    2015-01-01

    Background Schistosomiasis is a neglected disease caused by a trematode of the genus Schistosoma that is second only to malaria in public health significance in Africa, South America, and Asia. Praziquantel (PZQ) is the drug of choice to treat this disease due to its high cure rates and no significant side effects. However, in the last years increasingly cases of tolerance to PZQ have been reported, which has caused growing concerns regarding the emergency of resistance to this drug. Methodology/Principal Findings Here we describe the selection of a parasitic strain that has a stable resistance phenotype to PZQ. It has been reported that drug resistance in helminths might involve efflux pumps such as members of ATP-binding cassette transport proteins, including P-glycoprotein and multidrug resistance-associated protein families. Here we evaluate the role of efflux pumps in Schistosoma mansoni resistance to PZQ, by comparing the efflux pumps activity in susceptible and resistant strains. The evaluation of the efflux activity was performed by an ethidium bromide accumulation assay in presence and absence of Verapamil. The role of efflux pumps in resistance to PZQ was further investigated comparing the response of susceptible and resistant parasites in the absence and presence of different doses of Verapamil, in an ex vivo assay, and these results were further reinforced through the comparison of the expression levels of SmMDR2 RNA by RT-PCR. Conclusions/Significance This work strongly suggests the involvement of Pgp-like transporters SMDR2 in Praziquantel drug resistance in S. mansoni. Low doses of Verapamil successfully reverted drug resistance. Our results might give an indication that a combination therapy with PZQ and natural or synthetic Pgp modulators can be an effective strategy for the treatment of confirmed cases of resistance to PZQ in S. mansoni. PMID:26445012

  12. Comparative efficacy of one versus two doses of praziquantel on cure rate of Schistosoma mansoni infection and re-infection in Mayuge District, Uganda

    DEFF Research Database (Denmark)

    Tukahebwa, Edridah M.; Vennervald, Birgitte J; Nuwaha, Fred

    2013-01-01

    BACKGROUND: The current recommended control strategy for schistosomiasis is annual treatment using 40 mg/kg of praziquantel. However, praziquantel is only effective on adult worms and giving a second dose may increase its efficacy. We assessed the effect of one versus two doses of praziquantel...... months after treatment. RESULTS: Those who received two doses were more likely to be cured (69.7%) compared to those who received a single dose (47.9%) (¿(2) = 18.5, p ... intensity. However, there is no added advantage on reduction of S. mansoni re-infection by administering two doses of praziquantel. CLINICAL TRIALS.GOV IDENTIFIER: NCT00215267....

  13. Prospective European-wide multicentre study on a blood based real-time PCR for the diagnosis of acute schistosomiasis

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    Wichmann Dominic

    2013-01-01

    Full Text Available Abstract Background Acute schistosomiasis constitutes a rare but serious condition in individuals experiencing their first prepatent Schistosoma infection. To circumvent costly and time-consuming diagnostics, an early and rapid diagnosis is required. So far, classic diagnostic tools such as parasite microscopy or serology lack considerable sensitivity at this early stage of Schistosoma infection. To validate the use of a blood based real-time polymerase chain reaction (PCR test for the detection of Schistosoma DNA in patients with acute schistosomiasis who acquired their infection in various endemic regions we conducted a European-wide prospective study in 11 centres specialized in travel medicine and tropical medicine. Methods Patients with a history of recent travelling to schistosomiasis endemic regions and freshwater contacts, an episode of fever (body temperature ≥38.5°C and an absolute or relative eosinophil count of ≥700/μl or 10%, were eligible for participation. PCR testing with DNA extracted from serum was compared with results from serology and microscopy. Results Of the 38 patients with acute schistosomiasis included into the study, PCR detected Schistosoma DNA in 35 patients at initial presentation (sensitivity 92%. In contrast, sensitivity of serology (enzyme immunoassay and/or immunofluorescence assay or parasite microscopy was only 70% and 24%, respectively. Conclusion For the early diagnosis of acute schistosomiasis, real-time PCR for the detection of schistosoma DNA in serum is more sensitive than classic diagnostic tools such as serology or microscopy, irrespective of the region of infection. Generalization of the results to all Schistosoma species may be difficult as in the study presented here only eggs of S. mansoni were detected by microscopy. A minimum amount of two millilitre of serum is required for sufficient diagnostic accuracy.

  14. Factors influencing phagocytosis of Salmonella typhimurium by macrophages in murine schistosomiasis

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    Muniz-Junqueira Maria Imaculada

    1997-01-01

    Full Text Available We investigated the influence of Salmonella typhimurium load and specific antibodies on phagocytosis in schistosomiasis. Macrophages from Schistosoma mansoni-infected mice showed depressed capacity to increase the phagocytosis in the presence of a high bacterial load, due to a reduced involvement of these cells in phagocytosis and to a deficient ability to increase the number of phagocytosed bacteria. Normal and Salmonella-infected mice increased their phagocytic capacity when exposed to a high bacterial load. Antibody to Salmonella increased the phagocytic capacity of macrophages from Schistosoma-infected mice due to an increase in the number of bacteria phagocytosed but caused no modification in the number of macrophages engaged in phagocytosis. Our data indicate that macrophages from Schistosoma-infected mice work close to their functional limit, since no increase in phagocytosis was observed after increasing the bacterial load. Specific antibodies can improve their phagocytic capacity and, therefore, could help clearing concurrent infection.

  15. Schistosoma mansoni and Host-Parasite Interactions

    NARCIS (Netherlands)

    S.M-C.A. de Walick (Saskia)

    2015-01-01

    markdownabstract__Abstract__ Blood-dwelling parasitic trematodes (flatworms) of the genus Schistosoma cause the disease schistosomiasis or Bilharzia. There are 5 different Schistosoma species that infect humans and many other infecting different mammals. Over 200 million people worldwide are

  16. Schistosomiasis and malignancy | Lemmer | South African Medical ...

    African Journals Online (AJOL)

    It is generally accepted that schistosomiasis, if not causative, is at least associated with malignancy. In this review, the epidemiology of schistosomiasis and bladder carcinoma, as well as the role of chronic bladder infection, are discussed together with known carcinogenic factors, possible abnormal vitamin metabolism ...

  17. Community perceptions of schistosomiasis transmission, prevalence ...

    African Journals Online (AJOL)

    Most respondents were familiar with the snails' habitats, but had poor knowledge on aquatic plants harbouring snails, as 57% of the respondents did not know about aquatic plants being associated with schistosomiasis snails. Only 3% of the respondents associated snails with schistosomiasis transmission. Sixty percent ...

  18. Intestinal Schistosomiasis and the Associated Transmission Factors ...

    African Journals Online (AJOL)

    Africa, affecting populations living where water supply and sanitation are poor and inadequate. Pre-school aged children (PSAC) have ... Keywords: Intestinal schistosomiasis prevalence, Pre-school children, Rwanda. Background. Schistosomiasis is a .... facilities (Republic of Rwanda, 2012). Study design and population.

  19. The risk of schistosomiasis in Zimbabwean triathletes

    African Journals Online (AJOL)

    incidence of schistosomiasis was 64%. Exposure of triathletes to fresh-water dam swimming in Zimbabwe ... Humans may become infected with schistosomiasis by bathing, wading or immersing limbs in infested ... questionnaire enquiring about other recreational activities in fresh water, and whether they had recently (in the ...

  20. [Parasitological profile of two forms of schistosomiasis (urinary and intestinal forms) at ten sites in Burkina Faso (Sub-Saharan Africa country)].

    Science.gov (United States)

    Zongo, Dramane; Kabre, B Gustave; Dayeri, Dianou; Savadogo, Boubacar; Poda, Jean-Noël

    2013-01-01

    In spite of great progress in schistosomiasis control during the last decade in Burkina Faso, this disease remains a public health concern in the country. Indeed, our study consisted of the analysis of parasitological data related to Schistosoma haematobium and Schistosoma mansoni and in malacological investigations. The prevalence rate of Schistosoma haematobium varies from 3.3% to 50.4% and from 3.3% to 39.1% for Schistosoma mansoni, but only in the western part of Burkina Faso. Schoolboys are more infested than girls, but the phenomenon is reversed in adults. Biomphalaria pfeifferi, Bulinus truncatus, Bulinus senegalensis and Bulinus globosus were collected during this study. Thus, the behavioral factors as well as the dynamics and the distribution of the intermediate mollusks play a major role in the persistence of the disease. Copyright © 2013. Published by Elsevier SAS.

  1. Cross-immunoreactivity between anti-potato apyrase antibodies and mammalian ATP diphosphohydrolases: potential use of the vegetal protein in experimental schistosomiasis

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    P Faria-Pinto

    2006-10-01

    Full Text Available We have previously showed that Schistosoma mansoni ATP-diphosphohydrolase and Solanum tuberosum potato apyrase share epitopes and the vegetable protein has immunostimulatory properties. Here, it was verified the in situ cross-immunoreactivity between mice NTPDases and anti-potato apyrase antibodies produced in rabbits, using confocal microscopy. Liver samples were taken from Swiss Webster mouse 8 weeks after infection with S. mansoni cercariae, and anti-potato apyrase and TRITC-conjugated anti-rabbit IgG antibody were tested on cryostat sections. The results showed that S. mansoni egg ATP diphosphohydrolase isoforms, developed by anti-potato apyrase, are expressed in miracidial and egg structures, and not in granulomatous cells and hepatic structures (hepatocytes, bile ducts, and blood vessels. Therefore, purified potato apyrase when inoculated in rabbit generates polyclonal sera containing anti-apyrase antibodies that are capable of recognizing specifically S. mansoni ATP diphosphohydrolase epitopes, but not proteins from mammalian tissues, suggesting that autoantibodies are not induced during potato apyrase immunization. A phylogenetic tree obtained for the NTPDase family showed that potato apyrase had lower homology with mammalian NTPDases 1-4, 7, and 8. Further analysis of potato apyrase epitopes could implement their potential use in schistosomiasis experimental models.

  2. Comparative evaluation of Schistosoma mansoni, Schistosoma intercalatum, and Schistosoma haematobium alkaline phosphatase antigenicity by the alkaline phosphatase immunoassay (APIA).

    Science.gov (United States)

    Cesari, I M; Ballén, D E; Mendoza, L; Ferrer, A; Pointier, J-P; Kombila, M; Richard-Lenoble, D; Théron, A

    2014-04-01

    To know if alkaline phosphatase (AP) from schistosomes other than Schistosoma mansoni can be used as diagnostic marker for schistosomiasis in alkaline phosphatase immunocapture assay (APIA), we comparatively tested n-butanol extracts of adult worm membranes from a Venezuelan (JL) strain of S. mansoni (Ven/AWBE/Sm); a Cameroonian (EDEN) strain of Schistosoma intercalatum (Cam/AWBE/Si) and a Yemeni strain of Schistosoma haematobium (Yem/AWBE/Sh). APIA was evaluated with sera of patients from Venezuela, Senegal, and Gabon infected with S. mansoni, from Gabon infected with S. intercalatum or S. haematobium, from Chine infected with Schistosoma japonicum and from Cambodian patients infected with Schistosoma mekongi. Results indicate that 92.5% (37/40) of Venezuela sera, 75% (15/20) of Senegal sera, 39.5% (17/43) of S. haematobium sera, and 19.2% (5/26) S. intercalatum sera were APIA-positive with the Ven/AWBE/Sm preparation. APIA with the Cam/AWBE/Si preparation showed that 53.8% of S. intercalatum-positive sera had anti-AP antibodies, and 51.2% S. haematobium-positive sera cross-immunocapturing the S. intercalatum AP. APIA performed with Yem/AWBE/Sh showed that 55.8% S. haematobium sera were positive. Only two out of nine S. japonicum sera were APIA-positive with the Ven/AWBE/Sm and Cam/AWBE/Si, and no reaction was observed with Cambodian S. mekongi-positive sera. AP activity was shown to be present in all the schistosome species/strains studied. The use of APIA as a tool to explore the APs antigenicity and the presence of Schistosoma sp. infections through the detection of anti-Schistosoma sp. AP antibodies in a host, allowed us to demonstrate the antigenicity of APs of S. mansoni, S. intercalatum, and S. haematobium.

  3. Tratamento da hipertensão pulmonar esquistossomótica Treatment of schistosomiasis-associated pulmonary hypertension

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    Ricardo de Amorim Correa

    2011-04-01

    Full Text Available A esquistossomose mansoni é a terceira doença parasitária endêmica mais prevalente do mundo. Estima-se que mais de 200 milhões de pessoas estejam infectadas com uma das espécies do parasita Schistosoma. Dessas, 270.000 pessoas (4,6% são portadoras de hipertensão arterial pulmonar, que é associada à forma hepatoesplênica da doença. Essa alta prevalência coloca a hipertensão pulmonar esquistossomótica como a causa mais frequente de hipertensão pulmonar no mundo. Entretanto, o tratamento dirigido especificamente ao acometimento vascular pulmonar não está ainda estabelecido. Relatamos o caso de uma paciente portadora dessa doença que foi tratada com um inibidor de fosfodiesterase-5 (sildenafil com resultados satisfatórios.Schistosomiasis mansoni is the third most prevalent endemic parasitic disease in the world. It is estimated that over 200 million people are infected with parasites belonging to one of the Schistosoma species. Of those, 270,000 people (4.6% suffer from pulmonary arterial hypertension, which is associated with the hepatosplenic form of the disease. This high prevalence makes schistosomiasis-associated pulmonary hypertension the leading cause of pulmonary hypertension worldwide. However, no specific treatment for the pulmonary vascular component of the disease has yet been devised. We report the case of a patient with schistosomiasis-associated pulmonary hypertension who was treated satisfactorily with a phosphodiesterase-5 inhibitor (sildenafil.

  4. Integrated community-directed intervention for schistosomiasis and soil transmitted helminths in western Kenya – a pilot study

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    Mwinzi Pauline NM

    2012-08-01

    Full Text Available Abstract Background Schistosome and soil-transmitted helminth (STH infections are recognized as major global public health problems, causing severe and subtle morbidity, including significant educational and nutritional effects in children. Although effective and safe drugs are available, ensuring access to these drugs by all those at risk of schistosomiasis and STHs is still a challenge. Community-directed intervention (CDI has been used successfully for mass distribution of drugs for other diseases such as onchocerciasis and lymphatic filariasis. A national control programme is yet to be instituted in Kenya and evidence for cost-effective strategies for reaching most affected communities is needed. This study evaluated the effectiveness and feasibility of the CDI strategy in the control of schistosomiasis and STHs, in East Uyoma location, Rarieda district, a community of western Kenya that is highly endemic for both infections. Results Pre-treatment prevalence of S. mansoni averaged 17.4% (range 5-43% in the entire location. Treatment coverage in different villages ranged from 54.19 to 96.6% by community drug distributor (CDD records. Assessment from a household survey showed coverage of 52.3 -91.9% while the proportion of homesteads (home compounds covered ranged from 54.9-98.5%. Six months after one round of drug distribution, the prevalence levels of S. mansoni, hookworm and Trichuris trichura infections were reduced by 33.2%, 69.4% and 42.6% respectively. Conclusions This study shows that CDI is an accepted and effective strategy in the mass treatment of schistosomiasis and STH infections in resource constrained communities in Kenya and may be useful in similar communities elsewhere. A controlled trial comparing CDI and school based mass drug administration to demonstarte their relative advantages is ongoing.

  5. Evaluation of the CCA Immuno-Chromatographic Test to Diagnose Schistosoma mansoni in Minas Gerais State, Brazil.

    Science.gov (United States)

    Silveira, Alda Maria Soares; Costa, Emanuele Gama Dutra; Ray, Debalina; Suzuki, Brian M; Hsieh, Michael H; Fraga, Lucia Alves de Oliveira; Caffrey, Conor R

    2016-01-01

    The Kato-Katz (KK) stool smear is the standard test for the diagnosis of Schistosoma mansoni infection, but suffers from low sensitivity when infections intensities are moderate to low. Thus, misdiagnosed individuals remain untreated and contribute to the disease transmission, thereby forestalling public health efforts to move from a modality of disease control to one of elimination. As an alternative, the urine-based diagnosis of schistosomiasis mansoni via the circulating cathodic antigen immuno-chromatographic test (CCA-ICT) has been extensively evaluated in Africa with the conclusion that it may replace the KK test in areas where prevalences are moderate or high. The objective was to measure the performance of the CCA-ICT in a sample study population composed of residents from non-endemic and endemic areas for schistosomiasis mansoni in two municipalities of Minas Gerais state, Brazil. Volunteers (130) were classified into three infection status groups based on duplicate Kato-Katz thick smears from one stool sample (2KK test): 41 negative individuals from non-endemic areas, 41 negative individuals from endemic areas and 48 infected individuals from endemic areas. Infection status was also determined by the CCA-ICT and infection exposure by antibody ELISA (enzyme-linked immunosorbent assay) to S. mansoni soluble egg antigen (SEA) and soluble (adult) worm antigen preparation (SWAP). Sensitivity and specificity were influenced by whether the trace score visually adjudicated in the CCA-ICT was characterized as positive or negative for S. mansoni infection. An analysis of a two-graph receiver operating characteristic was performed to change the cutoff point. When the trace score was interpreted as a positive rather than as a negative result, the specificity decreased from 97.6% to 78.0% whereas sensitivity increased from 68.7% to 85.4%. A significantly positive correlation between the CCA-ICT scores and egg counts was identified (r = 0.6252, p = 0.0001). However

  6. Evaluation of the CCA Immuno-Chromatographic Test to Diagnose Schistosoma mansoni in Minas Gerais State, Brazil.

    Directory of Open Access Journals (Sweden)

    Alda Maria Soares Silveira

    2016-01-01

    Full Text Available The Kato-Katz (KK stool smear is the standard test for the diagnosis of Schistosoma mansoni infection, but suffers from low sensitivity when infections intensities are moderate to low. Thus, misdiagnosed individuals remain untreated and contribute to the disease transmission, thereby forestalling public health efforts to move from a modality of disease control to one of elimination. As an alternative, the urine-based diagnosis of schistosomiasis mansoni via the circulating cathodic antigen immuno-chromatographic test (CCA-ICT has been extensively evaluated in Africa with the conclusion that it may replace the KK test in areas where prevalences are moderate or high.The objective was to measure the performance of the CCA-ICT in a sample study population composed of residents from non-endemic and endemic areas for schistosomiasis mansoni in two municipalities of Minas Gerais state, Brazil. Volunteers (130 were classified into three infection status groups based on duplicate Kato-Katz thick smears from one stool sample (2KK test: 41 negative individuals from non-endemic areas, 41 negative individuals from endemic areas and 48 infected individuals from endemic areas. Infection status was also determined by the CCA-ICT and infection exposure by antibody ELISA (enzyme-linked immunosorbent assay to S. mansoni soluble egg antigen (SEA and soluble (adult worm antigen preparation (SWAP. Sensitivity and specificity were influenced by whether the trace score visually adjudicated in the CCA-ICT was characterized as positive or negative for S. mansoni infection. An analysis of a two-graph receiver operating characteristic was performed to change the cutoff point. When the trace score was interpreted as a positive rather than as a negative result, the specificity decreased from 97.6% to 78.0% whereas sensitivity increased from 68.7% to 85.4%. A significantly positive correlation between the CCA-ICT scores and egg counts was identified (r = 0.6252, p = 0

  7. Bladder Morbidity and Hepatic Fibrosis in Mixed Schistosoma haematobium and S. mansoni Infections: A Population-Wide Study in Northern Senegal

    Science.gov (United States)

    Meurs, Lynn; Mbow, Moustapha; Vereecken, Kim; Menten, Joris; Mboup, Souleymane; Polman, Katja

    2012-01-01

    Background The global distribution map of schistosomiasis shows a large overlap of Schistosoma haematobium- and S. mansoni-endemic areas in Africa. Yet, little is known about the consequences of mixed Schistosoma infections for the human host. A recent study in two neighboring co-endemic communities in Senegal indicated that infection intensities of both species were higher in mixed than in single infections. Here, we investigated the relationship between mixed Schistosoma infections and morbidity in the same population. So far, this has only been studied in children. Methods Schistosoma infection was assessed by microscopy. Schistosoma-specific morbidity was assessed by ultrasound according to WHO guidelines. Multivariable logistic regression models were used to identify independent risk factors for morbidity. Principal Findings Complete parasitological and morbidity data were obtained from 403 individuals. Schistosoma haematobium-specific bladder morbidity was observed in 83% and S. mansoni-specific hepatic fibrosis in 27% of the participants. Bladder morbidity was positively associated with S. haematobium infection intensity (OR = 1.9 (95% CI 1.3–2.9) for a 10-fold increase in intensity). Moreover, people with mixed infections tended to have less bladder morbidity than those with single S. haematobium infections (OR = 0.3 (95% CI 0.1–1.1)). This effect appeared to be related to ectopic S. mansoni egg elimination in urine. Hepatic fibrosis on the other hand was not related to S. mansoni infection intensity (OR = 0.9 (95% CI 0.6–1.3)), nor to mixed infections (OR = 1.0 (95% CI 0.7–1.7)). Conclusions/Significance This is the first population-wide study on the relationship between mixed Schistosoma infections and morbidity. Mixed infections did not increase the risk of S. mansoni-associated morbidity. They even tended to reduce the risk of S. haematobium-associated morbidity, suggesting a protective effect of S. mansoni infection on bladder

  8. Evolution of schistosomiasis-induced pathology after therapy and interruption of exposure to schistosomes: a review of ultrasonographic studies.

    Science.gov (United States)

    Richter, J

    2000-10-23

    Ultrasonography (US) is suitable for diagnosing schistosomiasis-related organic pathology and is particularly useful to assess its evolution after therapy and/or interruption of exposure to the Schistosoma parasites. Evolution of pathology after treatment: Regression of hepatic abnormalities in Schistosma mansoni-infected children and adolescents has been observed already from 7 months post-therapy on. This does, however, not occur in all cases: individual differences are great ranging from spontaneous regression of pathology without treatment to persistence of pathology lasting for years after therapy even without re-infection. Intensity and duration of exposure, different parasite strains, patients' age and genetic background all influence the evolution of pathology. In communities at continuous exposure to S. mansoni infection, repeated re-treatment is required to control hepatosplenic morbidity. In Schistosoma japonicum infection, changes around the portal tree may regress, but characteristic diffuse abnormalities described as 'network pattern' abnormalities do not resolve. In Schistosoma haematobium infection bladder abnormalities and urinary tract obstruction frequently resolve after treatment. Clinically relevant pathology may resurge from 1 year after therapy on if exposure continues. Subjects with more advanced pathology before therapy, appear to be at higher risk of pathology re-appearance. Evolution of pathology after interruption of exposure to schistosomiasis: Knowledge on the evolution of pathology induced by S. mansoni is limited to some reports in emigrants and to the experience of ultrasonographists working in areas, where transmission has been partially interrupted. Due to the longevity of the parasite, infection may last for many years. Even after elimination of the parasites severe pathology may persist for long. In S. haematobium infection spontaneous healing after interruption of re-exposure may occur, but cases have been reported where

  9. SmTRC1, a novel Schistosoma mansoni DNA transposon, discloses new families of animal and fungi transposons belonging to the CACTA superfamily

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    Verjovski-Almeida Sergio

    2006-11-01

    Full Text Available Abstract Background The CACTA (also called En/Spm superfamily of DNA-only transposons contain the core sequence CACTA in their Terminal Inverted Repeats (TIRs and so far have only been described in plants. Large transcriptome and genome sequence data have recently become publicly available for Schistosoma mansoni, a digenetic blood fluke that is a major causative agent of schistosomiasis in humans, and have provided a comprehensive repository for the discovery of novel genes and repetitive elements. Despite the extensive description of retroelements in S. mansoni, just a single DNA-only transposon belonging to the Merlin family has so far been reported in this organism. Results We describe a novel S. mansoni transposon named SmTRC1, for S. mansoni Transposon Related to CACTA 1, an element that shares several characteristics with plant CACTA transposons. Southern blotting indicates approximately 30–300 copies of SmTRC1 in the S. mansoni genome. Using genomic PCR followed by cloning and sequencing, we amplified and characterized a full-length and a truncated copy of this element. RT-PCR using S. mansoni mRNA followed by cloning and sequencing revealed several alternatively spliced transcripts of this transposon, resulting in distinct ORFs coding for different proteins. Interestingly, a survey of complete genomes from animals and fungi revealed several other novel TRC elements, indicating new families of DNA transposons belonging to the CACTA superfamily that have not previously been reported in these kingdoms. The first three bases in the S. mansoni TIR are CCC and they are identical to those in the TIRs of the insects Aedes aegypti and Tribolium castaneum, suggesting that animal TRCs may display a CCC core sequence. Conclusion The DNA-only transposable element SmTRC1 from S. mansoni exhibits various characteristics, such as generation of multiple alternatively-spliced transcripts, the presence of terminal inverted repeats at the extremities of

  10. In vivo T cell depletion regulates resistance and morbidity in murine schistosomiasis

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    Phillips, S.M.; Linette, G.P.; Doughty, B.L.; Byram, J.E.; Von Lichtenberg, F.

    1987-08-01

    These studies assessed the roles of subpopulations of T lymphocytes in inducing and modulating resistance to schistosomiasis and thereby influencing subsequent morbidity. C57BL/6 mice were depleted in vivo of Lyt-1+, Lyt-2+, and L3T4+ cells by the daily administration of monoclonal antibodies. The development of protective immunity, induced by exposure to irradiated Schistosoma mansoni cercariae as expressed in depleted animals, was compared to that demonstrated in undepleted, normal, and congenitally athymic C57BL/6 mice. The development of morbidity was determined by spleen weight, portal pressure and reticuloendothelial system activity. The results indicated that depletion of specific subpopulations of T lymphocytes minimally affected the primary development of parasites; however, depletion strongly influenced the development of resistance to the parasite and subsequent morbidity due to infection. Depletion of T lymphocytes by anti-Lyt-1+ or anti-L3T4+ antibody decreased the development of resistance, antibody and delayed-type hypersensitivity directed against schistosome antigens. Morbidity due to disease was increased. Depletion of Lyt-2+ cells produced opposite changes with augmented resistance and reduced morbidity. Congenitally athymic mice developed minimal resistance and morbidity. Moreover, resistance was inversely related to the morbidity shown by a given animal. These studies indicate that the development of protective immunity to S. mansoni cercariae is regulated by discrete subpopulations of T lymphocytes. The feasibility of decreasing morbidity by increasing specific immunologically mediated resistance is suggested.

  11. Spatial distribution of schistosomiasis foci on Itamaracá Island, Pernambuco, Brazil

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    CS Barbosa

    2004-08-01

    Full Text Available Acute cases of schistosomiasis have been found on the coastal area of Pernambuco, Brazil, due to environmental disturbances and disorderly occupation of the urban areas. This study identifies and spatially marks the main foci of the snail host species, Biomphalaria glabrata on Itamaracá Island. The chaotic occupation of the beach resorts has favoured the emergence of transmission foci, thus exposing residents and tourists to the risk of infection. A database covering five years of epidemiological investigation on snails infected by Schistosoma mansoni in the island was produced with information from the geographic positioning of the foci, number of snails collected, number of snails tested positive, and their infection rate. The spatial position of the foci were recorded through the Global Positioning System (GPS, and the geographical coordinates were imported by AutoCad. The software packages ArcView and Spring were used for data processing and spatial analysis. AutoCad 2000 was used to plot the pairs of coordinates obtained from GPS. Between 1998 and 2002 5009 snails, of which 12.2% were positive for S. mansoni, were collected in Forte Beach. A total of 27 foci and areas of environmental risk were identified and spatially analyzed allowing the identification of the areas exposed to varying degrees of risk.

  12. [Urinary schistosomiasis in ancient Egypt].

    Science.gov (United States)

    Ziskind, Bernard

    2009-12-01

    First described by Theodor Bilharz in 1851, Schistosoma haematobium, the worm responsible for urinary schistosomiasis, was a major health problem along the Nile Valley until the present days. Haematuria, the main symptom of this parasitic disease, was known and treated in Egyptian medical papyri since 1550 B.C. A relationship between haematuria and the god Seth was envisaged. Sir Marc Armand Ruffer, pioneer of paleopathology, found (1910) calcified Schistosoma eggs in Egyptian mummies of the xxth dynasty, establishing that bilharzia plagued ancient Egypt people. The ELISA method demonstrated the Schistosoma circulating anodic antigen in 45% of mummies studied.

  13. Acute schistosomiasis: clinical, diagnostic and therapeutic features Esquistossomose aguda: aspectos clínicos, diagnósticos e terapêuticos

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    J. R. Lambertucci

    1993-10-01

    Full Text Available Three distinct syndromes caused by schistosomiasis have been described: cercarial dermatitis or swimmer's itch, acute schistosomiasis or Katayama fever, and chronic schistosomiasis. Complications of acute schistosomiasis have also been reported. The absence of a serological marker for the acute stage has hindered early diagnosis and treatment. Recently, an ELISA test using KLH (keyhole limpet haemocyanin as antigen, has proved useful in differentiating acute from chronic schistosomiasis mansoni. Clinical and experimental evidence indicate that steroids act synergistically with schistosomicides in the treatment of Katayama syndrome. In this paper, clinical, diagnostic and therapeutic features of acute schistosomiasis are updated.A esquistossomose apresenta-se clinicamente em três formas distintas: dermatite cercariana, esquistossomose aguda ou febre de Katayama e esquistossomose crônica. Há na literatura relatos de complicações da fase aguda. A ausencia de um marcador sorológico simples e confiável tem dificultado o diagnóstico precoce e, como consequência, o tratamento adequado de pacientes na fase aguda da doença. Recentemente, o teste de ELISA, realizado com o antígeno KLM (hemocianina do caramujo Megathura crenulata, tem se mostrado util na identificação dos pacientes com febre de Katayama. Evidências clínicas e experimentais apontam no sentido de uma ação sinérgica entre os corticosteróides e os esquistossomicidas no tratamento da esquistossomose toxêmica. Neste artigo, alguns aspectos clínicos, diagnósticos e terapêuticos da esquistossomose aguda são atualizados.

  14. Mapping and prediction of schistosomiasis in Nigeria using compiled survey data and Bayesian geospatial modelling

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    Uwem F. Ekpo

    2013-05-01

    Full Text Available Schistosomiasis prevalence data for Nigeria were extracted from peer-reviewed journals and reports, geo-referenced and collated in a nationwide geographical information system database for the generation of point prevalence maps. This exercise revealed that the disease is endemic in 35 of the country’s 36 states, including the federal capital territory of Abuja, and found in 462 unique locations out of 833 different survey locations. Schistosoma haematobium, the predominant species in Nigeria, was found in 368 locations (79.8% covering 31 states, S. mansoni in 78 (16.7% locations in 22 states and S. intercalatum in 17 (3.7% locations in two states. S. haematobium and S. mansoni were found to be co-endemic in 22 states, while co-occurrence of all three species was only seen in one state (Rivers. The average prevalence for each species at each survey location varied between 0.5% and 100% for S. haematobium, 0.2% to 87% for S. mansoni and 1% to 10% for S. intercalatum. The estimated prevalence of S. haematobium, based on Bayesian geospatial predictive modelling with a set of bioclimatic variables, ranged from 0.2% to 75% with a mean prevalence of 23% for the country as a whole (95% confidence interval (CI: 22.8-23.1%. The model suggests that the mean temperature, annual precipitation and soil acidity significantly influence the spatial distribution. Prevalence estimates, adjusted for school-aged children in 2010, showed that the prevalence is <10% in most states with a few reaching as high as 50%. It was estimated that 11.3 million children require praziquantel annually (95% CI: 10.3-12.2 million.

  15. A Schistosoma haematobium-specific real-time PCR for diagnosis of urogenital schistosomiasis in serum samples of international travelers and migrants.

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    Lieselotte Cnops

    Full Text Available BACKGROUND: Diagnosis of urogenital schistosomiasis by microscopy and serological tests may be elusive in travelers due to low egg load and the absence of seroconversion upon arrival. There is need for a more sensitive diagnostic test. Therefore, we developed a real-time PCR targeting the Schistosoma haematobium-specific Dra1 sequence. METHODOLOGY/PRINCIPAL FINDINGS: The PCR was evaluated on urine (n = 111, stool (n = 84 and serum samples (n = 135, and one biopsy from travelers and migrants with confirmed or suspected schistosomiasis. PCR revealed a positive result in 7/7 urine samples, 11/11 stool samples and 1/1 biopsy containing S. haematobium eggs as demonstrated by microscopy and in 22/23 serum samples from patients with a parasitological confirmed S. haematobium infection. S. haematobium DNA was additionally detected by PCR in 7 urine, 3 stool and 5 serum samples of patients suspected of having schistosomiasis without egg excretion in urine and feces. None of these suspected patients demonstrated other parasitic infections except one with Blastocystis hominis and Entamoeba cyst in a fecal sample. The PCR was negative in all stool samples containing S. mansoni eggs (n = 21 and in all serum samples of patients with a microscopically confirmed S. mansoni (n = 22, Ascaris lumbricoides (n = 1, Ancylostomidae (n = 1, Strongyloides stercoralis (n = 1 or Trichuris trichuria infection (n = 1. The PCR demonstrated a high specificity, reproducibility and analytical sensitivity (0.5 eggs per gram of feces. CONCLUSION/SIGNIFICANCE: The real-time PCR targeting the Dra1 sequence for S. haematobium-specific detection in urine, feces, and particularly serum, is a promising tool to confirm the diagnosis, also during the acute phase of urogenital schistosomiasis.

  16. A malacological survey in the Manso Power Plant, State of Mato Grosso, Brazil: new records of freshwater snails, including transmitters of schistosomiasis and exotic species

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    Monica Ammon Fernandez

    2014-07-01

    Full Text Available Introduction Schistosomiasis is a parasitic disease of public health concern in Brazil, and the construction of hydroelectric dams, in addition to increasing permanent human settlement and tourism, has created conditions suitable for the establishment of mollusks that can transmit schistosomiasis. Such areas require a number of actions to prevent the establishment of schistosomiasis. This paper reports on a freshwater malacological survey carried out in the geographical area of the Manso Power Plant. Methods Mollusks were collected in 18 municipalities in the State of Mato Grosso between February 2002 and February 2004 (qualitative study and from April 2009 to February 2011 (quantitative study. Results Thirty-one species of mollusks were collected, including newly recorded species (Antillorbis nordestensis and Burnupia ingae. In addition, the geographic distributions of known species, including Biomphalaria straminea, a snail vector of Schistosoma mansoni, were expanded. A total of 4,507 specimens were collected in the APM Manso reservoir (Usina Hidrelétrica de Aproveitamento Múltiplo de Manso during the quantitative study, and Biomphalaria amazonica was found in six of the 10 localities analyzed. The Afroasiatic species Melanoides tuberculata, introduced after February 2009, was the dominant species (relative abundance 94.96%. Conclusions The study area is epidemiologically important due to the occurrence of B. straminea and B. amazonica, which are vectors of schistosomiasis, and M. tuberculata, a snail host of Centrocestus formosanus, which is responsible for centrocestiasis transmission. Observations of M. tuberculata and the exotic freshwater clams Corbicula fluminea and Corbicula largillierti raise concerns about biodiversity.

  17. A tale of two neglected tropical infections: using GIS to assess the spatial and temporal overlap of schistosomiasis and leprosy in a region of Minas Gerais, Brazil.

    Science.gov (United States)

    Phillips, David Alexander; Ferreira, José Antonio; Ansah, Deidra; Teixeira, Herica Sa; Kitron, Uriel; Filippis, Thelma de; Alcântara, Marcelo H de; Fairley, Jessica K

    2017-04-01

    Despite public health efforts to reduce the global burden of leprosy, gaps remain in the knowledge surrounding transmission of infection. Helminth co-infections have been associated with a shift towards the lepromatous end of the disease spectrum, potentially increasing transmission in co-endemic areas. Using this biologically plausible association, we conducted a geographic information systems (GIS) study to investigate the spatial associations of schistosomiasis and leprosy in an endemic area of Minas Gerais (MG), Brazil. Data on new cases of Mycobacterium leprae and Schistosoma mansoni infections from 2007-2014 were retrieved from the Brazilian national notifiable diseases information system for seven municipalities in and surrounding Vespasiano, MG. A total of 139 cases of leprosy and 200 cases of schistosomiasis were mapped to a municipality level. For one municipality, cases were mapped to a neighborhood level and a stratified analysis was conducted to identify spatial associations. A relative risk of 6.80 [95% confidence interval (CI) 1.46 - 31.64] of leprosy was found in neighborhoods with schistosomiasis. Incidence rates of leprosy increased with corresponding incidence rates of schistosomiasis, and the temporal trends of both infections were similar. The associations found in this project support the hypothesis that helminth infections may influence the transmission of leprosy in co-endemic areas.

  18. A tale of two neglected tropical infections: using GIS to assess the spatial and temporal overlap of schistosomiasis and leprosy in a region of Minas Gerais, Brazil

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    David Alexander Phillips

    Full Text Available BACKGROUND Despite public health efforts to reduce the global burden of leprosy, gaps remain in the knowledge surrounding transmission of infection. Helminth co-infections have been associated with a shift towards the lepromatous end of the disease spectrum, potentially increasing transmission in co-endemic areas. OBJECTIVES Using this biologically plausible association, we conducted a geographic information systems (GIS study to investigate the spatial associations of schistosomiasis and leprosy in an endemic area of Minas Gerais (MG, Brazil. METHODS Data on new cases of Mycobacterium leprae and Schistosoma mansoni infections from 2007-2014 were retrieved from the Brazilian national notifiable diseases information system for seven municipalities in and surrounding Vespasiano, MG. A total of 139 cases of leprosy and 200 cases of schistosomiasis were mapped to a municipality level. For one municipality, cases were mapped to a neighborhood level and a stratified analysis was conducted to identify spatial associations. FINDINGS A relative risk of 6.80 [95% confidence interval (CI 1.46 - 31.64] of leprosy was found in neighborhoods with schistosomiasis. Incidence rates of leprosy increased with corresponding incidence rates of schistosomiasis, and the temporal trends of both infections were similar. CONCLUSIONS The associations found in this project support the hypothesis that helminth infections may influence the transmission of leprosy in co-endemic areas.

  19. Schistosomiasis differentially affects vasoconstrictor responses: up-regulation of 5-HT receptor-mediated aorta contraction

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    Suellen D'Arc dos Santos Oliveira

    2011-06-01

    Full Text Available Schistosomiasis, classified by the World Health Organization as a neglected tropical disease, is an intravascular parasitic disease associated to a chronic inflammatory state. Evidence implicating inflammation in vascular dysfunction continues to mount, which, broadly defined, reflects a failure in the control of intracellular Ca2+ and consequently, vascular contraction. Therefore, we measured aorta contraction induced by 5-hydroxytryptamine (5-HT and endothelin-1 (ET-1, two important regulators of vascular contraction. Isometric aortic contractions were determined in control and Schistosoma mansoni-infected mice. In the infected animals, 5-HT induced a 50% higher contraction in relation to controls and we also observed an increased contraction in response to Ca2+ mobilisation from sarcoplasmic reticulum. Nevertheless, Rho kinase inhibition reduced the contraction in response to 5-HT equally in both groups, discarding an increase of the contractile machinery sensitivity to Ca2+. Furthermore, no alteration was observed for contractions induced by ET-1 in both groups. Our data suggest that an immune-vascular interaction occurs in schistosomiasis, altering vascular contraction outside the mesenteric portal system. More importantly, it affects distinct intracellular signalling involved in aorta contraction, in this case increasing 5-HT receptor signalling.

  20. Reduced uptake of mass treatment for schistosomiasis control in absence of food

    DEFF Research Database (Denmark)

    Muhumuza, Simon; Olsen, Annette; Katahoire, Anne

    2015-01-01

    BACKGROUND: Sustaining high uptake of praziquantel is key for long-term control of schistosomiasis. During mass treatment in 2013, we randomized 12 primary schools into two groups; one group received education messages for schistosomiasis prevention for two months prior to mass treatment, while...... the other, in addition to the education messages, received a pre-treatment snack shortly before mass treatment. The uptake of praziquantel in the snack schools was 94 % compared to 79 % in the non-snack schools. During mass treatment in 2014, no snack was provided. We compared the uptake of praziquantel......, the difference in the geometric mean intensity of S. mansoni infection in both the snack and non-snack schools was not statistically significant; 38.3 eggs per gram of stool (epg) and 145.7 epg (p = 0.197) and 78.4 epg and 322.5 epg (p = 0.120), respectively. CONCLUSION: Our results show that in absence of food...

  1. Prevalence of schistosomiasis among patients attending Qena General Hospital over the years 2011 and 2012.

    Science.gov (United States)

    Sayed, Fatma Galal; Alsalahy, Mohammed; Abd-el-Kader, Mohammed Sayed; Abdalla, Osama Hussein; Ahmed, Samar S

    2014-08-01

    Schistosomiasis is a public health problem in Egypt. To detect the prevalence of schistosomiasis in Qena Governorate, 1601 urine and stool samples of patients attending Qena General Hospital were examined of whom 1601 patients had urinary symptoms and 893 patients had dysentery and bloody stool. Sheets were filled out on each patient. Also, a total of 7590 Bulinus truncatus and Biomphalaria alexandrina snails were collected from water bodies in Qena Governorate. The overall prevalence of S. haematobium was 13.9%; with maximum among 6-18 year-old age group and higher in males than in females. Risk factors for S. haematobium infection were this age group; particularly males. However, males swim and play in water bodies and women wash cloths and utensils there, and children swimming or playing in canals. The S. haematobium peak of infection was in winter correlated with the highest prevalence in Dandara City, Qena City, Awlad-Amr and El Hijarat. S. mansoni were negative in the examined individuals. The infective rate among snails was 1.82% in B. truncatus and 0.0% among B. alexandrina and M. tuberculata.

  2. Effect of different stages of Schistosoma mansoni infection on the parasite burden and immune response to Strongyloides venezuelensis in co-infected mice.

    Science.gov (United States)

    de Rezende, Michelle Carvalho; Araújo, Emília Souza; Moreira, João Marcelo Peixoto; Rodrigues, Vanessa Fernandes; Rodrigues, Jailza Lima; Pereira, Cíntia A de Jesus; Negrão-Corrêa, Deborah

    2015-12-01

    Multiple schistosome and soil-transmitted nematode infections are frequently reported in human populations living in tropical areas of developing countries. In addition to exposure factors, the host immune response plays an important role in helminth control and morbidity in hosts with multiple infections; however, these aspects are difficult to evaluate in human populations. In the current study, female Swiss mice were simultaneously co-infected with Strongyloides venezuelensis and Schistosoma mansoni or infected with St. venezuelensis at 2, 4, or 14 weeks after Sc. mansoni infection. The simultaneously infected mice showed a similar parasite burden for St. venezuelensis compared with mono-infected mice. In contrast, there was a significant reduction of St. venezuelensis burden (primarily during the migration of the larvae) in mice that were previously infected with Sc. mansoni at the acute or chronic phase. Independent of the stage of Sc. mansoni infection, the St. venezuelensis co-infection was capable of inducing IL-4 production in the small intestine, increasing the IgE concentration in the serum and increasing eosinophilia in the lungs and intestine. This result suggests that the nematode infection stimulates local type 2 immune responses independently of the schistosomiasis stage. Moreover, previous Sc. mansoni infection stimulated early granulocyte infiltration in the lungs and trematode-specific IgM and IgG1 production that recognized antigens from St. venezuelensis infective larvae; these immune responses would act in the early control of St. venezuelensis larvae. Our data suggest that the effect of multiple helminth infections on host susceptibility and morbidity largely depends on the species of parasite and the immune response.

  3. Potential role of meflquine (antimalarial drug and methanol extract of Chenopodium ambrosioides and Sesbania sesban in mice infected with Schistosoma mansoni

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    Mohamed Abdel-Wahab El-Emam

    2015-08-01

    Full Text Available Objective: To elucidate the efficacy of mefloquine and methanol extract of the plants Chenopodium ambrosioides (C. ambrosioides and Sesbania sesban (S. sesban as a combined therapy for the treatment of Schistosoma mansoni (S. mansoni infected mice, and study the parasitological, biochemical and histological parameters of treated mice. Methods: Two groups of male Swiss Albino mice were infected with S. mansoni cercariae. The first group untreated served as control. The second group was orally treated with a single dose (200 mg/kg of mefloquine 3 weeks post infection, then subsequently divided into 2 subgroups; the first orally retreated with the plant extracts 1 000 mg/kg of S. sesban followed by 1 250 mg/kg of C. ambrosioides with an 1 h interval, for 2 successive days. The second sub-group was re-treated with the same (dose and method plant extracts after 7 weeks post infection. Results: The results showed that S. mansoni infected mice treated with mefloquine and the plants’ extracts 3 weeks post infection significantly (P < 0.01 reduced the worm burden/ mouse by 95.5% and the few worms recovered from sacrificed mice in this treatment failed to lay ova. Moreover, no worms were recovered from infected mice treated with mefloquine (3 weeks post infection and re-treated by the plant’s extracts at 7 weeks post infection. Also, treatment of infected mice with mefloquine followed by the plants’ extracts either at 3 or 7 weeks post infection ameliorated the activities of the serum enzymes alanine aminotransferase, aspartate aminotransferase, alkline phosphatase and acid phosphatase as well as the hepatic granulomatous lesions compared to infected untreated group. Conclusions: It is concluded that successive treatment of S. mansoni infected mice with mefloquine and methanol extract of the plants C. ambrosioides and S. sesban could be a promising device in the strategy of schistosomiasis control.

  4. Unique roles for lipids in Schistosoma mansoni.

    Science.gov (United States)

    Furlong, S T

    1991-02-01

    The dynamic interplay among lipids has been exploited by S. mansoni to evolve some unique processes that are vital for its long-term survival within the mammalian host. Lipids are required by the parasite not only to maintain its surface integrity and structural requirements but also for egg production and cell-cell signalling. However, S. mansoni is incapable of synthesizing essential lipids and must obtain these from its host. In this review, Stephen Furlong describes the roles and routes of acquisition o f lipids by this parasite.

  5. A esquistossomose mansoni no contexto da política de saúde brasileira Schistosoma mansoni in the context of the Brazilian health policy

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    Sandra Helena Cerrato Tibiriçá

    2011-01-01

    Full Text Available São muitos os fatores envolvidos na determinação da emergência e reemergência de doenças infecciosas. No caso da esquistossomose destacam-se os fatores biológicos como os relacionados ao habitat, às mutações e adaptações de microrganismos e hospedeiros, à resposta imunológica do hospedeiro e às adaptações bioecológicas de hospedeiros intermediários. Somam-se a esses, os não menos importantes fatores relacionados à gestão política, ocupação do ambiente e alocação de recursos financeiros. O Brasil reúne, hoje, importantes condições ecoepidemiológicas para a reemergência da esquistossomose e aumento da prevalência de algumas formas graves como mielorradiculopatia esquistossomótica, principalmente em áreas de baixa endemicidade. A expansão de suas fronteiras atinge os meios urbanos e rurais, destinados ao trabalho ou ao lazer, com comprometimento inclusive de setores de renda como o ecoturismo. Os avanços nas pesquisas acerca dos hospedeiros intermediário e definitivo do Schistosoma mansoni, para se transformarem em benefícios públicos, necessitam da sustentabilidade gerencial pública comprometida, interdisciplinar, fortalecida nas diferentes esferas de governo, vinculada ás sociedades civis tecnicamente capacitadas ao gerenciamento e comprometidas com as necessidades de saúde da população.There are many factors involved in the determination of the emergence and reemergence of infectious diseases. In the case of Schistosomiasis biological factors are highlighted as related to the habitat, to the microorganisms and hosts adaptations and mutations, to the immunologic reply of the host and to the bio-ecology adaptations of intermediate hosts. These are added to the not less important factors related to the management politics, occupation of the environment and allocation of financial resources. Brazil congregates, today, an important echo-epidemiologic conditions for the reemergence of Schistosomiasis. The

  6. Esquistossomose: nova ocorrência de Biomphalaria straminea em Belo Horizonte, Minas Gerais Schistosomiasis: new occurrence of Biomphalaria straminea in Belo Horizonte, Minas Gerais

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    Cecília Pereira de Souza

    1996-12-01

    Full Text Available Em Belo Horizonte, Minas Gerais, Brasil, a Biomphalaria straminea é encontrada na região da Pampulha. Recentemente, o molusco foi encontrado em valas da antiga Barragem de Santa Lúcia, foco extinto de esquistossomose transmitida por B. glabrata. Os moluscos foram coletados e examinados para verificar se estavam naturalmente infectados com Schistosoma mansoni. Os exemplares negativos foram usados para criação ou infecção com a cepa LE de S. mansoni, mantida no laboratório, e outra cepa VGS, obtida de ovos de fezes de escolar de Belo Horizonte. Dentre 1.890 moluscos capturados em 1994 e 1995, nenhum estava infectado com S. mansoni. Dentre 87 exemplares coletados no criadouro e expostos à cepa LE, nove (10,3% eliminaram cercárias; dentre 83 moluscos da F1, dez (12,0% eliminaram cercárias e dentre 88 exemplares coletados e expostos à cepa VGS, dez (11,3% eliminaram cercárias. Em Belo Horizonte, a esquistossomose é transmitida por B. glabrata e B. tenagophila. Entretanto, atualmente existe o risco de aparecimento de novo foco, no qual a B. straminea poderá vir a ser a transmissora, se medidas profiláticas adequadas não forem tomadas pelas autoridades responsáveis pela construção de um parque e lago no local.In Belo Horizonte, Minas Gerais, Brazil, the snail Biomphalaria straminea was found in the Pampulha region. Recently the snail was found in ditches in the old Santa Lúcia Reservoir, a now-extinct focus of schistosomiasis transmission by B. glabrata. The snails were collected and examined to verify whether they were naturally infected with Schistosoma mansoni. Negative specimens were used for breeding or infection with the LE strain of S. mansoni from the laboratory and another strain obtained from eggs found in the feces of a schoolchild (VGS from Belo Horizonte. Among the 1890 snails collected from 1994 to 1995, none were infected with S. mansoni. Among 87 snails collected and exposed to the LE strain, 9 (10.3% shed cercariae

  7. Inferences on the biochemical and environmental regulation of universal stress proteins from Schistosomiasis parasites

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    Mbah AN

    2013-05-01

    Full Text Available Andreas N Mbah,1,2 Ousman Mahmud,1 Omotayo R Awofolu,2 Raphael D Isokpehi11Center for Bioinformatics and Computational Biology, Department of Biology, Jackson State University, Jackson, MS, USA; 2Department of Environmental Sciences, College of Agriculture and Environmental Sciences, University of South Africa, Pretoria, South AfricaBackground: Human schistosomiasis is a freshwater snail-transmitted disease caused by parasitic flatworms of the Schistosoma genus. Schistosoma haematobium, Schistosoma mansoni, and Schistosoma japonicum are the three major species infecting humans. These parasites undergo a complex developmental life cycle, in which they encounter a plethora of environmental signals. The presence of genes encoding the universal stress protein (USP domain in the genomes of Schistosoma spp. suggests these flatworms are equipped to respond to unfavorable conditions. Though data on gene expression is available for USP genes, their biochemical and environmental regulation are incompletely understood. The identification of additional regulatory molecules for Schistosoma. USPs, which may be present in the human, snail, or water environments, could also be useful for schistosomiasis interventions.Methods: We developed a protocol that includes a visual analytics stage to facilitate integration, visualization, and decision making, from the results of sequence analyses and data collection on a set of 13 USPs from S. mansoni and S. japonicum.Results: Multiple sequence alignment identified conserved sites that could be key residues regulating the function of USPs of the Schistosoma spp. Based on the consistency and completeness of sequence annotation, we prioritized for further research the gene for a 184-amino-acid-long USP that is present in the genomes of the three human-infecting Schistosoma spp. Calcium, zinc, and magnesium ions were predicted to interact with the protein product of the gene.Conclusion: Given that the initial effects of

  8. Reduction of Urogenital Schistosomiasis with an Integrated Control Project in Sudan

    Science.gov (United States)

    Lee, Young-Ha; Jeong, Hoo Gn; Kong, Woo Hyun; Lee, Soon-Hyung; Cho, Han-Ik; Nam, Hae-Sung; Ismail, Hassan Ahmed Hassan Ahmed; Alla, Gibril Nouman Abd; Oh, Chung Hyeon; Hong, Sung-Tae

    2015-01-01

    Purpose Schistosomiasis remains a major public health concern in Sudan, particularly Schistosoma haematobium infection. This study presents the disease-reduction outcomes of an integrated control program for schistosomiasis in Al Jabalain locality of White Nile State, Sudan from 2009 through 2011. Methods The total population of the project sites was 482,902, and the major target group for intervention among them was 78,615 primary school students. For the cross-sectional study of the prevalence, urine and stool specimens were examined using the urine sedimentation method and the Kato cellophane thick smear method, respectively. To assess the impacts of health education for students and a drinking water supply facility at Al Hidaib village, questionnaire survey was done. Results The overall prevalence for S. haematobium and S. mansoni at baseline was 28.5% and 0.4%, respectively. At follow-up survey after 6–9 months post-treatment, the prevalence of S. haematobium infection was reduced to 13.5% (95% CI = 0.331–0.462). A higher reduction in prevalence was observed among girls, those with moderately infected status (around 20%), and residents in rural areas, than among boys, those with high prevalence (>40%), and residents in urban areas. After health education, increased awareness about schistosomiasis was checked by questionnaire survey. Also, a drinking water facility was constructed at Al Hidaib village, where infection rate was reduced more compared to that in a neighboring village within the same unit. However, we found no significant change in the prevalence of S. mansoni infection between baseline and follow-up survey (95% CI = 0.933–6.891). Conclusions At the end of the project, the prevalence of S. haematobium infection was reduced by more than 50% in comparison with the baseline rate. Approximately 200,000 subjects had received either praziquantel therapy, health education, or supply of clean water. To consolidate the achievements of this

  9. Antigens of worms and eggs showed a differentiated detection of specific IgG according to the time of Schistosoma mansoni infection in mice

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    Rafaella Fortini Queiroz Grenfell

    2012-08-01

    Full Text Available INTRODUCTION: The correlation between the immunological assay and the antibody titer can offer a tool for the experimental analysis of different phases of the disease. METHODS: Two simple immunological assays for Schistosoma mansoni in mice sera samples based on specific IgG detection for worms soluble antigens and eggs soluble antigens were standardized and evaluated in our laboratory. Fifty mice were used in negative and positive groups and the results obtained by enzyme-linked immunosorbent assays (ELISA assays were compared with the number of worms counted and the IgG titers at different times of infection. RESULTS: Data showed that ELISA using adult worm antigens (ELISA-SWAP presented a satisfactory correlation between the absorbance value of IgG titers and the individual number of worms counted after perfusion technique (R²=0.62. In addition, ELISA-SWAP differentially detected positive samples with 30 and 60 days post infection (p=0.011 and 0.003, respectively, whereas ELISA using egg antigens (ELISA-SEA detected samples after 140 days (p=0.03. CONCLUSIONS: These data show that the use of different antigens in immunological methods can be used as potential tools for the analysis of the chronological evolution of S. mansoni infection in murine schistosomiasis. Correlations with human schistosomiasis are discussed.

  10. Antigens of worms and eggs showed a differentiated detection of specific IgG according to the time of Schistosoma mansoni infection in mice.

    Science.gov (United States)

    Grenfell, Rafaella Fortini Queiroz; Martins, Watson Hermann; Silva-Moraes, Vanessa; Barata, Suedali Villas-Boas; Ribeiro, Elizandra Giani; Oliveira, Edward; Coelho, Paulo Marcos Zech

    2012-01-01

    The correlation between the immunological assay and the antibody titer can offer a tool for the experimental analysis of different phases of the disease. Two simple immunological assays for Schistosoma mansoni in mice sera samples based on specific IgG detection for worms soluble antigens and eggs soluble antigens were standardized and evaluated in our laboratory. Fifty mice were used in negative and positive groups and the results obtained by enzyme-linked immunosorbent assays (ELISA) assays were compared with the number of worms counted and the IgG titers at different times of infection. Data showed that ELISA using adult worm antigens (ELISA-SWAP) presented a satisfactory correlation between the absorbance value of IgG titers and the individual number of worms counted after perfusion technique (R²=0.62). In addition, ELISA-SWAP differentially detected positive samples with 30 and 60 days post infection (p=0.011 and 0.003, respectively), whereas ELISA using egg antigens (ELISA-SEA) detected samples after 140 days (p=0.03). These data show that the use of different antigens in immunological methods can be used as potential tools for the analysis of the chronological evolution of S. mansoni infection in murine schistosomiasis. Correlations with human schistosomiasis are discussed.

  11. Aluminum hydroxide associated to Schistosoma mansoni 22.6 kDa protein abrogates partial protection against experimental infection but not alter interleukin-10 production

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    Lucila GG Pacífico

    2006-10-01

    Full Text Available The need to develop a vaccine against schistosomiasis led several researches and our group to investigate proteins from Schistosoma mansoni as vaccine candidates. Sm22.6 is a protein from S. mansoni that shows high identity with Sj22.6 and Sh22.6 (79 and 91%, respectively. These proteins are associated with high levels of IgE and protection to reinfection. Previously, we have shown that Sm22.6 induced a partial protection of 34.5% when used together with Freund's adjuvant and produced a Th0 type of immune response with interferon-g and interleukin-4. In this work, mice were immunized with Sm22.6 alone or with aluminum hydroxide adjuvant and high levels of IgG, IgG1, and IgG2a were measured. Unfortunately, no protection was detected. Since IL-10 is a modulating cytokine in schistosomiasis, we also observed a high level of this molecule in splenocytes of vaccinated mice. In conclusion, we did not observe the adjuvant effect of aluminum hydroxide associated with rSm22.6 in protective immunity.

  12. Urinary schistosomiasis, perception and treatment-seeking ...

    African Journals Online (AJOL)

    structured questionnaire. The degree of awareness stood at 94.75% though none of the respondents knew the causative agent of urinary schistosomiasis. The number of respondents that accepted involvement in one water-related activity or the ...

  13. Fase aguda da esquistossomose mansoni

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    Edward Tonelli

    1972-10-01

    Full Text Available O A. faz um estudo panorâmico sobre a fase aguda da esquistossomose mansoni, abordando o quadro clínico e seu diagnóstico, os exames subsidiários, o diagnóstico diferencial, a terapêutica e os aspectos evolutivos. As manifestações clinicas dos períodos de incubação, de estado e de supressão são abordados. O diagnóstico da fase aguda é baseado em dado epidemiológico, 110 exame fisico e em exames subsidiários. O dado epidemiológico. em geral, é positivo, com menção a banho infectante, comumente 30 a 40 dias antes do início do quadro clínico e ao exame físico, encontramos hipertermia (38 - 4G°C, prostração, micropoliadenia hepatomegalia dolorosa em 95%, dos casos e esplenomegalia em 70% dos casos. Os exames prioritários para o diagnóstico são o exame parasiiológico de fezes seriado, que é positivo para ovos viáveis de S. mansoni e o leucograma seriado, que, geralmente, acusa leucocitose com eosinofilia. Em caso de dúvida ou para complementação diagnostica, podemos recorrer à endoscovia retal, ao oograma e á biópsia hepática. A endoscopia acusa, comumente, mucosa hiperêmica, edemaciada, friável, granulosa, com pontos hemorrágicos e o exame colhido por punção biópsia revela, entre outros achados, granulomas na fase necrótica-exsudativa. O diagnóstico diferencial deve ser feito com as seguintes entidades clínicas: gastroenterites. febre tifóide, disenteria bacilar, amebíase aguda, salmonelose septicêrnica prolongada, devendo, ainda, figurar a tuberculose miliar, abdome agudo, a G.N.D.A., a mononucleose infecciosa, a leptospirose, a hepatite e as poaneurites. A terapeutica é baseada nos cuidados gerais, na córticoterapia e na terapêutica específica. Observamos regressão dramática do quadro toxinfeccioso. nas primeiras 24 a 48 horas com a córticoterapia (prednisona que tem duração aproximada de 7 a 10 dias. A terapêutica específica (derivado nitrotiazolico = ambilhar e derivado hidroximet

  14. SCHISTOSOMA MANSONI OF THE CONUS MEDULARIS: CASE ...

    African Journals Online (AJOL)

    hi-tech

    , P.O Box 20723, Nairobi, Kenya. Request for reprints to: Dr. P.K. Wanyoike, Kenyatta National Hospital, P.O Box 20723, Nairobi, Kenya. SCHISTOSOMA MANSONI OF THE CONUS MEDULARIS: CASE REPORT. P. K. WANYOIKE and M. M. ...

  15. Metabonomic investigation of human Schistosoma mansoni infection

    DEFF Research Database (Denmark)

    Balog, Crina I.A.; Meissner, Axel; Göraler, Sibel

    2011-01-01

    involving a well-characterized cohort of 447 individuals from a rural area in Uganda near Lake Victoria with a high prevalence of Schistosoma mansoni, a species predominantly occurring in Africa including Madagascar and parts of South America. Cohort samples were collected from individuals at five time...

  16. Increased endothelial cell-leukocyte interaction in murine schistosomiasis: possible priming of endothelial cells by the disease.

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    Suellen D S Oliveira

    Full Text Available BACKGROUND AND AIMS: Schistosomiasis is an intravascular parasitic disease associated with inflammation. Endothelial cells control leukocyte transmigration and vascular permeability being modulated by pro-inflammatory mediators. Recent data have shown that endothelial cells primed in vivo in the course of a disease keep the information in culture. Herein, we evaluated the impact of schistosomiasis on endothelial cell-regulated events in vivo and in vitro. METHODOLOGY AND PRINCIPAL FINDINGS: The experimental groups consisted of Schistosoma mansoni-infected and age-matched control mice. In vivo infection caused a marked influx of leukocytes and an increased protein leakage in the peritoneal cavity, characterizing an inflamed vascular and cellular profile. In vitro leukocyte-mesenteric endothelial cell adhesion was higher in cultured cells from infected mice as compared to controls, either in the basal condition or after treatment with the pro-inflammatory cytokine tumor necrosis factor (TNF. Nitric oxide (NO donation reduced leukocyte adhesion to endothelial cells from control and infected groups; however, in the later group the effect was more pronounced, probably due to a reduced NO production. Inhibition of control endothelial NO synthase (eNOS increased leukocyte adhesion to a level similar to the one observed in the infected group. Besides, the adhesion of control leukocytes to endothelial cells from infected animals is similar to the result of infected animals, confirming that schistosomiasis alters endothelial cells function. Furthermore, NO production as well as the expression of eNOS were reduced in cultured endothelial cells from infected animals. On the other hand, the expression of its repressor protein, namely caveolin-1, was similar in both control and infected groups. CONCLUSION/SIGNIFICANCE: Schistosomiasis increases vascular permeability and endothelial cell-leukocyte interaction in vivo and in vitro. These effects are partially

  17. The prevalence of schistosomiasis in school-aged children as an appropriate indicator of its prevalence in the community

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    Ana Paula Braz Pereira

    2010-07-01

    Full Text Available School-aged children (6-15 years from the endemic area of Pernambuco were evaluated both as a target group for and an indicator of schistosomiasis control in the community. Parasitological data were drawn from baseline stool surveys of whole populations that were obtained to diagnose Schistosoma mansoni infection. Nineteen representative localities were selected for assessing the prevalence of schistosomiasis among individuals in the following age groups: 0-5, 6-15, 16-25, 26-40 and 41-80 years. For each locality, the prevalence in each age group was compared to that of the overall population using contingency table analysis. To select a reference group, the operational difficulties of conducting residential surveys were considered. School-aged children may be considered to be the group of choice as the reference group for the overall population for the following reasons: (i the prevalence of schistosomiasis in this age group had the highest correlation with the prevalence in the overall population (r = 0.967, (ii this age group is particularly vulnerable to infection and plays an important role in parasite transmission and (iii school-aged children are the main target of the World Health Organization in terms of helminth control. The Schistosomiasis Control Program should consider school-aged children both as a reference group for assessing the need for intervention at the community level and as a target group for integrated health care actions of the Unified Health System that are focused on high-risk groups.

  18. Gaining and sustaining schistosomiasis control

    DEFF Research Database (Denmark)

    Ezeamama, Amara E.; He, Chun-La; Shen, Ye

    2016-01-01

    chemotherapy (PCT) with praziquantel (PZQ)? This paper describes the process SCORE used to transform this question into a harmonized research protocol, the study design for answering this question, the village eligibility assessments and data resulting from the first year of the study. METHODS: Beginning......-aged children. Seven studies are currently being implemented in five African countries. During the first year, villages were screened for eligibility, and data were collected on prevalence and intensity of infection prior to randomisation and the implementation of different schemes of PZQ intervention...... strategies. RESULTS: These studies of different treatment schedules with PZQ will provide the most comprehensive data thus far on the optimal frequency and continuity of PCT for schistosomiasis infection and morbidity control. CONCLUSIONS: We expect that the study outcomes will provide data for decision...

  19. The therapeutic effect of the neuropeptide hormone somatostatin on Schistosoma mansoni caused liver fibrosis

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    Peeters Theo

    2005-06-01

    . mansoni caused increased hydroxyproline levels (9.37 ± 0.63 μmol at wk10; 9.65 ± 0.96 μmol at wk14 as compared to uninfected animals (1.06 ± 0.10 μmol. This significant increase in collagen content (P = 0.01; 0.007 respectively marks the fibrosis observed at these time points. Treatment with somatostatin resulted in a significant decrease in hydroxyproline levels both at wk10 (4.76 ± 0.58 μmol and at wk14 (5.8 ± 1.13 μmol (P = 0.01; 0.03 respectively. Endogenous somatostatin levels were increased at wk10 (297 ± 37.24 pg/ml and wk14 (206 ± 13.30 pg/ml of infection as compared to uninfected mice (119 ± 11.99 pg/ml (P = 0.01; 0.008 respectively. Circulating somatostatin levels in infected animals were not significantly affected by somatostatin treatment. Hepatocyte status remained unaltered and granulomas were not remarkably changed in size or cellularity. Conclusion Our experiments reveal an antifibrotic effect of somatostatin in schistosomiasis. We have previously shown that the somatostatin receptors SSTR2 and SSTR3 are present on the parasite egg and worms. We therefore hypothesize that somatostatin reduces either the number of parasite eggs or the secretion of fibrosis inducing-mediators. Our data suggest somatostatin may have therapeutic potential in S. mansoni mediated liver pathology.

  20. Study of the snail intermediate hosts for Schistosoma mansoni on Itamaracá Island in northeast Brazil: spatial displacement of Biomphalaria glabrata by Biomphalaria straminea.

    Science.gov (United States)

    Barbosa, Constança S; Barbosa, Verônica S; Nascimento, Wheverton C; Pieri, Otavio S; Araújo, Karina C G M

    2014-05-01

    In 2012 a malacological survey of the breeding sites of Biomphalaria glabrata and B. straminea , the two intermediate host snails of Schistosoma mansoni , was carried out on Itamaraca Island in Pernambuco, Brazil. This study has now been extended by studying the competition between the two species. Snails were collected and dissected to identify the species and tests were performed to verify S. mansoni infection. Student's t test was used to compare the proportion between the two species and their breeding sites and a parasitological survey was conducted among local residents, using the Kato-Katz method. The spatial distribution of the two snail species was determined using TerraView, while a snail density map was constructed by Kernel estimate. The survey identified two breeding sites for B. glabrata with 17 specimens and 19 breeding sites for B. straminea with 459 snails, all of them negative for S. mansoni infection. The statistical analysis revealed that the proportion of the numbers of specimens and breeding sites of B. straminea (37.84 ± 9.01) were significantly greater than those of B. glabrata (8.50 ± 6.50). Parasitological examinations from 41 residents diagnosed two cases of schistosomiasis with parasite loads of 60 and 84 eggs per 1 g of stool, respectively. This indiction of a competitive process between the two snail species requires monitoring of schistosomiasis in the resident and travelling human populations occupying this environment, which could potentially result in social and economic changes on the island risking its attraction as a centre for eco-tourism.

  1. [Ecological civilization and schistosomiasis control in Yujiang County].

    Science.gov (United States)

    Ai, Dong-Yun; Liu, Bu-Yun

    2012-02-01

    This article describes the main approach of ecological civilization construction and great changes and achievements in the original schistosomiasis endemic areas, Yujiang County, Jiangxi Province. Ecological civilization is an important part of schistosomiasis control work.

  2. Chemotherapeutic efficacy of a natural combination in the treatment of mansonic schistosomiasis: an experimental study

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    Rashad Abdul-Ghani

    2011-01-01

    Full Text Available Rashad Abdul-Ghani1, Naguiba Loutfy2, Manal Sheta3, Azza Hassan21Department of Medical Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen; 2Tropical Health Department, High Institute of Public Health, 3Department of Pathology, Medical Research Institute, Alexandria University, Alexandria, EgyptPurpose: Combination chemotherapy of Schistosoma mansoni has been studied previously, with praziquantel being the basis of combination. Artemether and myrrh are compounds of a natural origin that have been investigated experimentally and clinically against schistosomiasis. Artemether is used as an antimalarial drug, and has been used as a chemoprophylactic drug against Schistosoma japonica in China whereas myrrh extract is manufactured and prescribed as an antischistosomal drug in Egypt. The present study investigated the experimental efficacy of combining artemether and myrrh using three different protocols in mice infected with the Egyptian strain of S. mansoni.Methods: Experiments were performed on 40 eight-week-old female Swiss albino mice divided into three experimental groups and one control group. Assessment of efficacy was based on a suite of parasitologic and histopathologic parameters. Parasitologic parameters included reductions in total and female worm burdens, reductions in hepatic and intestinal wall tissue egg loads, and alterations in oogram patterns in the experimental groups compared to the infected untreated control. Histopathologic parameters comprised microscopic examination of liver sections stained with hematoxylin and eosin to study the reductions in the mean counts and diameters of hepatic granulomas as well as their healing ratios compared to the control.Results: Reductions of 43.9%–58.2% in total worm burdens and 42.4%–63.7% in female worm burdens were induced. Meanwhile, significant reductions of 63.1%–77.8% in eggs per gram of small intestinal tissue and of 56.5%–66.3% in eggs

  3. Immunization with PIII, a fraction of Schistosoma mansoni soluble adult worm antigenic preparation, affects nitric oxide production by murine spleen cells

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    Diana Magalhães de Oliveira

    1998-01-01

    Full Text Available Nitric oxide (NO is an important effector molecule involved in immune regulation and defense. NO produced by cytokine-activated macrophages was reported to be cytotoxic against the helminth Schistosoma mansoni. Identification and characterization of S. mansoni antigens that can provide protective immunity is crucial for understanding the complex immunoregulatory events that modulate the immune response in schistosomiasis. It is, then, essential to have available defined, purified parasite antigens. Previous work by our laboratory identified a fraction of S. mansoni soluble adult worm antigenic preparation (SWAP, named PIII, able to elicit significant in vitro cell proliferation and at the same time lower in vitro and in vivo granuloma formation when compared either to SEA (soluble egg antigen or to SWAP. In the present work we report the effect of different in vivo trials with mice on their spleen cells ability to produce NO. We demonstrate that PIII-immunization is able to significantly increase NO production by spleen cells after in vitro stimulation with LPS. These data suggest a possible role for NO on the protective immunity induced by PIII.

  4. High rate of failure in treatment of imported schistosomiasis

    DEFF Research Database (Denmark)

    Helleberg, Marie; Thybo, Sören

    2011-01-01

    There is an increasing number of imported cases of schistosomiasis in Europe, but there are only few studies on the efficacy of praziquantel for the treatment of schistosomiasis in non-endemic settings.......There is an increasing number of imported cases of schistosomiasis in Europe, but there are only few studies on the efficacy of praziquantel for the treatment of schistosomiasis in non-endemic settings....

  5. Schistosomiasis

    Science.gov (United States)

    ... to its preferred body part, depending on its species. These areas include the: Bladder Rectum Intestines Liver ... subtropical areas worldwide. Symptoms Symptoms vary with the species of worm and the phase of infection. Many ...

  6. Elimination of schistosomiasis: the tools required.

    Science.gov (United States)

    Bergquist, Robert; Zhou, Xiao-Nong; Rollinson, David; Reinhard-Rupp, Jutta; Klohe, Katharina

    2017-11-20

    Historically, the target in the schistosomiasis control has shifted from infection to morbidity, then back to infection, but now as a public health problem, before moving on to transmission control. Currently, all endemic countries are encouraged to increase control efforts and move towards elimination as required by the World Health Organization (WHO) roadmap for the global control of the neglected tropical diseases (NTDs) and the WHA65.21 resolution issued by the World Health Assembly. However, schistosomiasis prevalence is still alarmingly high and the global number of disability-adjusted life years (DALYs) due to this infection has in fact increased due to inclusion of some 'subtle' clinical symptoms not previously counted. There is a need to restart and improve efforts to reach the elimination goal. To that end, the first conference of the Global Schistosomiasis Alliance (GSA) Research Working Group was held in mid-June 2016 in Shanghai, People's Republic of China. It reviewed current progress in schistosomiasis control and elimination, identified pressing operational research gaps that need to be addressed and discussed new tools and strategies required to make elimination a reality. The articles emanating from the lectures and discussions during this meeting, together with some additional invited papers, have been collected as a special issue of the 'Infectious Diseases of Poverty' entitled 'Schistosomiasis Research: Providing the Tools Needed for Elimination', consisting of 26 papers in all. This paper refers to these papers and discusses critical questions arising at the conference related to elimination of schistosomiasis. The currently most burning questions are the following: Can schistosomiasis be eliminated? Does it require better, more highly sensitive diagnostics? What is the role of preventive chemotherapy at the elimination stage? Is praziquantel sufficient or do we need new drugs? Contemplating these questions, it is felt that the heterogeneity

  7. The use of protein hydrolysate improves the protein intestinal absorption in undernourished mice infected with Schistosoma mansoni

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    Coutinho Eridan M.

    2002-01-01

    Full Text Available Patients residing in endemic areas for schistosomiasis in Brazil are usually undernourished and when they develop the hepatosplenic clinical form of the disease should usually receive hospital care, many of them being in need of nutritional rehabilitation before specific treatment can be undertaken. In the mouse model, investigations carried out in our laboratory detected a reduced aminoacid uptake in undernourished animals which is aggravated by a superimposed infection with Schistosoma mansoni. However, in well-nourished infected mice no dysfunction occurs. In this study, we tried to improve the absorptive intestinal performance of undernourished mice infected with S. mansoni by feeding them with hydrolysed casein instead of whole casein. The values obtained for the coefficient of protein intestinal absorption (cpia among well-nourished mice were above 90% (either hydrolysed or whole protein. In undernourished infected mice, however, the cpia improved significantly after feeding them with hydrolysed casein, animals reaching values close to those obtained in well-nourished infected mice.

  8. An atlas for Schistosoma mansoni organs and life-cycle stages using cell type-specific markers and confocal microscopy.

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    James J Collins

    2011-03-01

    Full Text Available Schistosomiasis (bilharzia is a tropical disease caused by trematode parasites (Schistosoma that affects hundreds of millions of people in the developing world. Currently only a single drug (praziquantel is available to treat this disease, highlighting the importance of developing new techniques to study Schistosoma. While molecular advances, including RNA interference and the availability of complete genome sequences for two Schistosoma species, will help to revolutionize studies of these animals, an array of tools for visualizing the consequences of experimental perturbations on tissue integrity and development needs to be made widely available. To this end, we screened a battery of commercially available stains, antibodies and fluorescently labeled lectins, many of which have not been described previously for analyzing schistosomes, for their ability to label various cell and tissue types in the cercarial stage of S. mansoni. This analysis uncovered more than 20 new markers that label most cercarial tissues, including the tegument, the musculature, the protonephridia, the secretory system and the nervous system. Using these markers we present a high-resolution visual depiction of cercarial anatomy. Examining the effectiveness of a subset of these markers in S. mansoni adults and miracidia, we demonstrate the value of these tools for labeling tissues in a variety of life-cycle stages. The methodologies described here will facilitate functional analyses aimed at understanding fundamental biological processes in these parasites.

  9. Anthelmintic Activity of Crude Extract and Essential Oil of Tanacetum vulgare (Asteraceae against Adult Worms of Schistosoma mansoni

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    Loyana Silva Godinho

    2014-01-01

    Full Text Available Schistosomiasis, a parasitic disease caused by trematode flatworms of the genus Schistosoma, affects more than 200 million people worldwide, and its control is dependent on a single drug, praziquantel. Tanacetum vulgare (Asteraceae is used in folk medicine as a vermifuge. This study aimed to investigate the in vitro schistosomicidal activity of the crude extract (TV and the essential oil (TV-EO from the aerial parts of T. vulgare. TV-EO was obtained by hydrodistillation and analyzed by GC/MS, which allowed the identification of β-thujone (84.13% as the major constituent. TV and TV-EO, at 200 μg/mL, decreased motor activity and caused 100% mortality of all adult worms. At 100 and 50 μg/mL, only TV caused death of all adult worms, while TV-EO was inactive. TV (200 μg/mL was also able to reduce viability and decrease production of developed eggs. Confocal laser scanning microscopy showed morphological alterations in the tegument of the S. mansoni surface after incubation with TV (50 and 100 μg/mL. Quantitative analysis on the schistosomes tegument showed that TV caused changes in the numbers of tubercles of S. mansoni male worms in a dose-dependent manner. The findings suggest that T. vulgare is a potential source of schistosomicidal compounds.

  10. Anthelmintic Activity of Crude Extract and Essential Oil of Tanacetum vulgare (Asteraceae) against Adult Worms of Schistosoma mansoni

    Science.gov (United States)

    Godinho, Loyana Silva; Aleixo de Carvalho, Lara Soares; Barbosa de Castro, Clarissa Campos; Dias, Mirna Meana; Pinto, Priscila de Faria; Crotti, Antônio Eduardo Miller; Pinto, Pedro Luiz Silva; de Moraes, Josué; Da Silva Filho, Ademar A.

    2014-01-01

    Schistosomiasis, a parasitic disease caused by trematode flatworms of the genus Schistosoma, affects more than 200 million people worldwide, and its control is dependent on a single drug, praziquantel. Tanacetum vulgare (Asteraceae) is used in folk medicine as a vermifuge. This study aimed to investigate the in vitro schistosomicidal activity of the crude extract (TV) and the essential oil (TV-EO) from the aerial parts of T. vulgare. TV-EO was obtained by hydrodistillation and analyzed by GC/MS, which allowed the identification of β-thujone (84.13%) as the major constituent. TV and TV-EO, at 200 μg/mL, decreased motor activity and caused 100% mortality of all adult worms. At 100 and 50 μg/mL, only TV caused death of all adult worms, while TV-EO was inactive. TV (200 μg/mL) was also able to reduce viability and decrease production of developed eggs. Confocal laser scanning microscopy showed morphological alterations in the tegument of the S. mansoni surface after incubation with TV (50 and 100 μg/mL). Quantitative analysis on the schistosomes tegument showed that TV caused changes in the numbers of tubercles of S. mansoni male worms in a dose-dependent manner. The findings suggest that T. vulgare is a potential source of schistosomicidal compounds. PMID:24672320

  11. Seasonal patterns in the transmission of Schistosoma haematobium, S. mattheei and S. mansoni in the highveld region of Zimbabwe.

    Science.gov (United States)

    Chandiwana, S K; Christensen, N O; Frandsen, F

    1987-12-01

    The pattern of fluctuation in the population size of Bulinus globosus and Biomphalaria pfeifferi, in their infection rates with Schistosoma haematobium/S. mattheei and S. mansoni, respectively, and in the cercarial population size as monitored using hamster immersions, was elucidated in streams in the temperate highveld region of Zimbabwe over a 27-month period during 1982-1984. The results revealed that transmission of S. mansoni was erratic and unpredictable without a clearcut seasonal transmission pattern. In contrast, transmission of S. haematobium and S. mattheei exhibited a marked seasonal pattern, being most intensive during the hot, dry season (September-November) and markedly reduced during the cold, dry season (June-August). During the rainy (December-February) and warm, post-rainy (March-May) seasons transmission was moderate and variable, but occasionally intensive. The results also showed that rodent immersion is to be preferred to measurements of snail population size and snail infection rate in elucidating seasonality of transmission of schistosomiasis.

  12. Recombinant Mycobacterium bovis BCG expressing the Sm14 antigen of Schistosoma mansoni protects mice from cercarial challenge.

    Science.gov (United States)

    Varaldo, Paula B; Leite, Luciana C C; Dias, Waldely O; Miyaji, Eliane N; Torres, Fabio I G; Gebara, Vera C; Armôa, Geraldo R G; Campos, Adriano S; Matos, Denise C S; Winter, Nathalie; Gicquel, Brigitte; Vilar, Mônica M; McFadden, Johnjoe; Almeida, Marilia S; Tendler, Miriam; McIntosh, Douglas

    2004-06-01

    The Sm14 antigen of Schistosoma mansoni was cloned and expressed in Mycobacterium bovis BCG as a fusion with the Mycobacterium fortuitum beta-lactamase protein under the control of its promoter, pBlaF*; the protein was localized in the bacterial cell wall. The rBCG-Sm14 strain was shown to be relatively stable in cultured murine and bovine monocytes in terms of infectivity, bacterial persistence, and plasmid stability. The immunization of mice with rBCG-Sm14 showed no induction of anti-Sm14 antibodies; however, splenocytes of immunized mice released increased levels of gamma interferon upon stimulation with recombinant Sm14 (rSm14), indicating an induction of a Th1-predominant cellular response against Sm14. Mice immunized with one or two doses of rBCG-Sm14 and challenged with live S. mansoni cercaria showed a 48% reduction in worm burden, which was comparable to that obtained by immunization with three doses of rSm14 purified from Escherichia coli. The data presented here further enhance the status of Sm14 as a promising candidate antigen for the control of schistosomiasis and indicate that a one-dose regimen of rBCG-Sm14 could be considered a convenient means to overcome many of the practical problems associated with the successful implementation of a multiple-dose vaccine schedule in developing countries.

  13. Development of species-specific primers for identification of Biomphalaria arabica, the intermediate host of Schistosoma mansoni in Saudi Arabia.

    Science.gov (United States)

    Al-Quraishy, Saleh A; Bin Dajem, Saad M; Mostafa, Osama M; Ibrahim, Essam H; Al-Qahtani, Ahmed

    2014-01-01

    Schistosoma mansoni is mediated through the intermediate host Biomphalaria arabica which lives in Saudi Arabia. Molecular characterization and identification of this intermediate host are important for epidemiological studies of schistosomiasis. The present work aimed to determine the molecular variations among the populations of B. arabica found in Southern part of Saudi Arabia, and to develop species-specific primers for identification of these snails as a first step in the development of multiplex PCR for simultaneously identifying the snails and diagnosing its infections in a single step. Five populations of Saudi B. arabica snails were collected from freshwater bodies. Three populations were collected from Asser and two populations were collected from AL-Baha. Genomic DNA was extracted from snails and was amplified using five different RAPD-PCR primers. The banding patterns of amplified materials by primers P1 and P5 were identical in all populations. However, the rest primers displayed intra-specific differences among populations with variable degrees. Largest sizes of RAPD-PCR products were cloned into TA cloning vector as a preparatory step for DNA sequence analysis. After sequencing, similarity searches of obtained DNA sequences revealed that there are no similar sequences submitted to genebank data bases and its associated banks. The results obtained will be helpful in the development of simultaneous identification of B. arabica snails and diagnosis of S. mansoni infection within it in a single step by an implementation of multiplex PCR.

  14. Ultrastructural study of morphological changes in Schistosoma mansoni after in vitro exposure to the monoterpene rotundifolone.

    Science.gov (United States)

    Matos-Rocha, Thiago José; Cavalcanti, Marília Gabriela Dos Santos; Barbosa-Filho, José Maria; Lúcio, Ana Silvia Suassuna Carneiro; Veras, Dyana Leal; Marques, Márcia Ortiz Mayo; Alves, Luiz Carlos; Brayner, Fábio André

    2017-01-01

    Schistosomiasis, a parasitic disease caused by trematode flatworms of the genus Schistosoma, affects more than 200 million people worldwide, and its control is dependent on a single drug, praziquantel. Here, we report the in vitro effect of rotundifolone, a monoterpene isolated from Mentha x villosa (Lamiaceae), on Schistosoma mansoni adult worms. The in vitro effect of rotundifolone on adult Schistosoma mansoni was evaluated by analysis of behavior and mortality and through a scanning electron microscopic analysis of ultrastructural changes in the tegument of the worms. At concentrations of 3.54 and 7.09μg/mL-1 rotundifolone, no worm mortality was observed at any of the sampling intervals. A minor reduction in movement of the tail, suckers, and gynecophoral canal membrane was observed after 96 h of exposure to 7.09μg/mL-1 rotundifolone. At 70.96μg/mL-1, a lack of movement was observed from 72h onwards and all worms were deemed dead; similar effects were observed at 48h with 177.4μg/mL-1, and at 24h with 354.8μg/mL-1 and 700.96μg/mL-1. Rotundifolone also caused death of all parasites and separation of coupled pairs into individual males and females after 24h at 354.8μg/mL-1. The main changes in the tegument induced by the different ROT treatments were: after 24h incubation, bubble lesions spread over the entire body and loss of tubercles occurred in some regions of the ventral region.

  15. Whole-Organ Isolation Approach as a Basis for Tissue-Specific Analyses in Schistosoma mansoni

    Science.gov (United States)

    Hahnel, Steffen; Lu, Zhigang; Wilson, R. Alan; Grevelding, Christoph G.; Quack, Thomas

    2013-01-01

    Background Schistosomiasis is one of the most important parasitic diseases worldwide, second only to malaria. Schistosomes exhibit an exceptional reproductive biology since the sexual maturation of the female, which includes the differentiation of the reproductive organs, is controlled by pairing. Pathogenicity originates from eggs, which cause severe inflammation in their hosts. Elucidation of processes contributing to female maturation is not only of interest to basic science but also considering novel concepts combating schistosomiasis. Methodology/Principal Findings To get direct access to the reproductive organs, we established a novel protocol using a combined detergent/protease-treatment removing the tegument and the musculature of adult Schistosoma mansoni. All steps were monitored by scanning electron microscopy (SEM) and bright-field microscopy (BF). We focused on the gonads of adult schistosomes and demonstrated that isolated and purified testes and ovaries can be used for morphological and structural studies as well as sources for RNA and protein of sufficient amounts for subsequent analyses such as RT-PCR and immunoblotting. To this end, first exemplary evidence was obtained for tissue-specific transcription within the gonads (axonemal dynein intermediate chain gene SmAxDynIC; aquaporin gene SmAQP) as well as for post-transcriptional regulation (SmAQP). Conclusions/Significance The presented method provides a new way of getting access to tissue-specific material of S. mansoni. With regard to many still unanswered questions of schistosome biology, such as elucidating the molecular processes involved in schistosome reproduction, this protocol provides opportunities for, e.g., sub-transcriptomics and sub-proteomics at the organ level. This will promote the characterisation of gene-expression profiles, or more specifically to complete knowledge of signalling pathways contributing to differentiation processes, so discovering involved molecules that may

  16. A rationale for schistosomiasis control in elementary schools of the rainforest zone of pernambuco, Brazil.

    Science.gov (United States)

    Favre, Tereza C; Pereira, Ana P B; Galvão, Aline F; Zani, Luciana C; Barbosa, Constança S; Pieri, Otávio S

    2009-01-01

    Since its beginning in 1999, the Schistosomiasis Control Program within the Unified Health System (PCE-SUS) has registered a cumulative coverage of just 20% of the population from the Rainforest Zone of Pernambuco (ZMP), northeast Brazil. This jeopardizes the accomplishment of the minimum goal of the Fifty-Fourth World Health Assembly, resolution WHA54.19, of providing treatment for schistosomiasis and soil-transmitted helminthiases (STH) to 75% of school-aged children at risk, which requires attending at least 166,000 residents in the 7-14 age range by year 2010 in that important endemic area. In the present study, secondary demographic and parasitological data from a representative municipality of the ZMP are analyzed to provide evidence that the current, community-based approach to control schistosomiasis and STH is unlikely to attain the WHA-54.19 minimum goal and to suggest that school-based control actions are also needed. Data available on the PCE-SUS activities related to diagnosis and treatment of the population from the study municipality were obtained from the State Secretary of Health of Pernambuco (SES/PE) for 2002-2006, complemented by the Municipal Secretary of Health (SMS) for 2003-2004. Data from a school-based stool survey carried out by the Schistosomiasis Reference Service of the Oswaldo Cruz Foundation (SRE/Fiocruz) in 2004 were used to provide information on infection status variation among school-aged children (7-14 years). According to the SES, from 2004 to 2006, only 2,977 (19.5%) of the estimated 15,288 residents of all ages were examined, of which 396 (13.3%) were positive for Schistosoma mansoni. Among these, only 180 (45.5%) were treated. According to the SMS, of the 1,766 examined in the 2003-2004 population stool survey 570 (32.3%) were children aged 7-14 years. One year later, the SRE/Fiocruz school survey revealed that the infection status among those children remained unchanged at 14%-15% prevalence. By 2006, the school

  17. A multivalent chimeric vaccine composed of Schistosoma mansoni SmTSP-2 and Sm29 was able to induce protection against infection in mice.

    Science.gov (United States)

    Pinheiro, C S; Ribeiro, A P D; Cardoso, F C; Martins, V P; Figueiredo, B C P; Assis, N R G; Morais, S B; Caliari, M V; Loukas, A; Oliveira, S C

    2014-07-01

    Schistosoma mansoni is a blood fluke parasite responsible for schistosomiasis. The best long-term strategy to control schistosomiasis is through immunization combined with drug treatment. In this study, we cloned, expressed and purified SmTSP-2 fused to the N- and C-terminal halves of Sm29 and tested these chimeras as vaccine candidates using an adjuvant approved to be used in humans. The results demonstrated that vaccination with SmTSP-2 fused to N- or C-terminus of Sm29-induced reduction in worm burden and liver pathology when compared to control animals. Additionally, we detected high levels of mouse-specific IgG, IgG1 and IgG2a against both chimeras and significant amounts of IFN-γ and TNF-α and no IL-4. Finally, studies with sera from patients resistant to infection and living in schistosomiasis endemic areas revealed high levels of specific IgG to both chimeras when compared to healthy individuals. In conclusion, SmTSP-2/Sm29 chimeras tested here induced partial protection against infection and might be a potential vaccine candidate. © 2014 John Wiley & Sons Ltd.

  18. Schistosoma mansoni major egg antigen Smp40: molecular modeling and potential immunoreactivity for anti-pathology vaccine development

    Directory of Open Access Journals (Sweden)

    Mohamed F Abouel-Nour

    2006-06-01

    Full Text Available The pathogenesis of Schistosoma mansoni infection is largely determined by host T-cell mediated immune responses such as the granulomatous response to tissue deposited eggs and subsequent fibrosis. The major egg antigens have a valuable role in desensitizing the CD4+ Th cells that mediate granuloma formation, which may prevent or ameliorate clinical signs of schistosomiasis.S. mansoni major egg antigen Smp40 was expressed and completely purified. It was found that the expressed Smp40 reacts specifically with anti-Smp40 monoclonal antibody in Western blotting. Three-dimensional structure was elucidated based on the similarity of Smp40 with the small heat shock protein coded in the protein database as 1SHS as a template in the molecular modeling. It was figured out that the C-terminal of the Smp40 protein (residues 130 onward contains two alpha crystallin domains. The fold consists of eight beta strands sandwiched in two sheets forming Greek key. The purified Smp40 was used for in vitro stimulation of peripheral blood mononuclear cells from patients infected with S. mansoni using phytohemagglutinin mitogen as a positive control. The obtained results showed that there is no statistical difference in interferon-g, interleukin (IL-4 and IL-13 levels obtained with Smp40 stimulation compared with the control group (P > 0.05 for each. On the other hand, there were significant differences after Smp40 stimulation in IL-5 (P = 0.006 and IL-10 levels (P < 0.001 compared with the control group. Gaining the knowledge by reviewing the literature, it was found that the overall pattern of cytokine profile obtained with Smp40 stimulation is reported to be associated with reduced collagen deposition, decreased fibrosis, and granuloma formation inhibition. This may reflect its future prospect as a leading anti-pathology schistosomal vaccine candidate.

  19. Detection of Schistosoma mansoni eggs in feces through their interaction with paramagnetic beads in a magnetic field.

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    Candida Fagundes Teixeira

    Full Text Available BACKGROUND: Diagnosis of intestinal schistosomiasis in low endemic areas is a problem because often control measures have reduced egg burdens in feces to below the detection limits of classical coproparasitological methods. Evaluation of molecular methods is hindered by the absence of an established standard with maximum sensitivity and specificity. One strategy to optimize method performance, where eggs are rare events, is to examine large amounts of feces. A novel diagnostic method for isolation of Schistosoma mansoni eggs in feces, and an initial evaluation of its performance is reported here. METHODOLOGY/PRINCIPAL FINDINGS: Known amounts of S. mansoni eggs were seeded into 30 g of normal human feces and subjected to a sequence of spontaneous sedimentation, sieving, Ritchie method, incubation and isolation through interaction with paramagnetic beads. Preliminary tests demonstrated the efficacy of lectins as ligands, but they also indicated that the paramagnetic beads alone were sufficient to isolate the eggs under a magnetic field through an unknown mechanism. Eggs were identified by microscopic inspection, with a sensitivity of 100% at 1.3 eggs per gram of feces (epg. Sensitivity gradually decreased to 25% at a concentration of 0.1 epg. In a preliminary application of the new method to the investigation of a recently established focus in southern Brazil, approximately 3 times more eggs were detected than with the thick-smear Kato-Katz method. CONCLUSIONS/SIGNIFICANCE: The novel S. mansoni detection method may significantly improve diagnosis of infections with low burdens in areas of recent introduction of the parasite, areas under successful control of transmission, or in infected travelers. It may also improve the evaluation of new treatments and vaccines.

  20. Morphological Characteristics of Schistosoma mansoni PZQ-resistant and -susceptible Strains are Different in Presence of Praziquantel

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    António ePinto-Almeida

    2016-04-01

    Full Text Available Schistosomiasis is one of the most common human parasitic diseases whose socioeconomic impact is only surpassed by malaria. Praziquantel (PZQ is the only drug commercially available for the treatment of all schistosome species causing disease in humans. However, there has been stronger evidences of PZQ-resistance on Schistosoma mansoni and thus it is very important to study the phenotypic characteristics associated with it. The aim of this study was to evaluate morphological alterations in S. mansoni PZQ-resistant adult worms and eggs, by comparing a PZQ-resistant strain obtained under PZQ drug pressure with a PZQ-susceptible strain. For this, scanning electronic microscopy was used to assess tegumental responsiveness of both strains under PZQ exposure, and optical microscopy allowed the monitoring of worms and eggs in the presence of the drug. Those assays showed that PZQ-susceptible worms exposed to the drug had more severe tegumental damages than the resistant one, which had only minor alterations. Moreover, contrary to what occurred in the susceptible strain, resistant worms were viable after PZQ exposure and gradually regaining full motility after removal of the drug. Eggs from resistant strain parasites are considerably smaller than those from susceptible strain. Our results suggest that there might be a difference in the tegument composition of the resistant strain and that worms are less responsive to PZQ. Changes observed in egg morphology might imply alterations in the biology of schistosomes associated to PZQ-resistance, which could impact on transmission and pathology of the disease. Moreover, we propose a hypothetical scenario where there is a different egg tropism of the S. mansoni resistant strain. This study is the first comparing two strains that only differ in their resistance characteristics, which makes it a relevant step in the search for resistance determinants.

  1. Effectiveness of a pre-treatment snack on the uptake of mass treatment for schistosomiasis in Uganda

    DEFF Research Database (Denmark)

    Muhumuza, Simon; Olsen, Annette; Katahoire, Anne

    2014-01-01

    -treatment snack on uptake of mass treatment.Methods and Findings:In a cluster randomized trial carried out in Jinja district, Uganda, 12 primary schools were randomized into two groups; one received education messages for schistosomiasis prevention for two months prior to mass treatment, while the other......, in addition to the education messages, received a pre-treatment snack shortly before mass treatment. Four weeks after mass treatment, uptake of praziquantel was assessed among a random sample of 595 children in the snack schools and 689 children in the non-snack schools as the primary outcome. The occurrence...... of side effects and the prevalence and mean intensity of Schistosoma mansoni infection were determined as the secondary outcomes. Uptake of praziquantel was higher in the snack schools, 93.9% (95% CI 91.7%-95.7%), compared to that in the non-snack schools, 78.7% (95% CI 75.4%-81.7%) (p = 0...

  2. Schistosoma mansoni: kinetics of glomerulonephritis in Mongolian gerbils and its correlation with intensity and duration of infection

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    Chisty M.M.

    2002-06-01

    Full Text Available The frequent occurrence of glomerular lesions in schistosomiasis patients has been reported, although appropriate animal models for the study of schistosomal glomerulonephritis have not been developed. To analyze the relationship between glomerulonephritis and Schistosoma mansoni infection, gerbils, Meriones unguiculatus, were infected with different number of cercariae and sacrificed at different weeks of post infection. Fifty cercariae were the optimum dose to produce the disease, glomerulonephritis, without early death of the animal. Infected gerbils showed heterogeneous types of glomerular lesions with increased serum creatinine level. Immune complex deposition was not detected at glomeruli of infected gerbils even by means of immunuofluorescence and also by transmission electron microscopy. However, infiltration of mononuclear cells in and around some of the altered glomeruli was observed. Immunohistochemical staining, using monoclonal antibody (HUSM-M.g. 15 specific to gerbils T-cells, revealed significant infiltration of T-cells. These findings suggest that T-cells might be involved in the development of glomerulonephritis. Gerbil could be a useful model to clarify the role of T-cells in the development of glomerulonephritis of schistosomiasis

  3. 20 YEARS OF PROGRESS IN SCHISTOSOMIASIS RESEARCH

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    M. Sudomo

    2012-09-01

    Full Text Available Preliminary studies of schistosomiasis in Indonesia were made in the late 1930's and the early 1940's. The first human case of S. japonicum was discovered by Muller and Tesch from the Lindu valley of Central Sulawesi (Celebes. Early epidemiological studies prior to World War II demonstrated that, in addition to man, wild deer and domestic dogs served as reservoir hosts, "and subsequent microscopic examination of adult worms from these mammals confirmed them to be S. japonicum. Although extensive snail surveys were conducted at that time, the molluscan host was not found. The schistosomiasis problem in Lindu Valley virtually remained dormant until the 1970's. In the 1970's there was a resurgence of interest in the epidemiology of schistosomiasis in Indonesia. A new schistosomiasis area in the Napu valley was discovered. During this period, the intermediate host, Oncomelania hupensis was found in the Lake Lindu valley. This confirmed that the uisease situation in Indonesia was, in fact, a form of classical oriental schistosomiasis similar in its biology and transmission to that found in the Philippines, Japan, and China. The molluscan host of S. japonicum in the Lake Lindu Valley was subsequently described as a new species, O. h. iindoensis, and is most similar to O. h. quadrasi, the vector host in the Philippines. The disease occurs now only in two very isolated areas, the Lake Lindu valley and Napu valley in Central Sulawesi.

  4. Anthelmintic activity in vivo of epiisopiloturine against juvenile and adult worms of Schistosoma mansoni.

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    Maria A Guimarães

    2015-03-01

    Full Text Available Schistosomiasis is a serious disease currently estimated to affect more that 207 million people worldwide. Due to the intensive use of praziquantel, there is increasing concern about the development of drug-resistant strains. Therefore, it is necessary to search for and investigate new potential schistosomicidal compounds. This work reports the in vivo effect of the alkaloid epiisopiloturine (EPI against adults and juvenile worms of Schistosoma mansoni. EPI was first purified its thermal behavior and theoretical solubility parameters charaterised. In the experiment, mice were treated with EPI over the 21 days post-infection with the doses of 40 and 200 mg/kg, and 45 days post-infection with single doses of 40, 100 and 300 mg/kg. The treatment with EPI at 40 mg/kg was more effective in adult worms when compared with doses of 100 and 300 mg/kg. The treatment with 40 mg/kg in adult worms reduced parasite burden significantly, lead to reduction in hepatosplenomegaly, reduced the egg burden in faeces, and decreased granuloma diameter. Scanning electron microscopy revealed morphological changes to the parasite tegument after treatment, including the loss of important features. Additionally, the in vivo treatment against juvenile with 40 mg/kg showed a reduction of the total worm burden of 50.2%. Histopathological studies were performed on liver, spleen, lung, kidney and brain and EPI was shown to have a DL50 of 8000 mg/kg. Therefore EPI shows potential to be used in schistosomiasis treatment. This is the first time that schistosomicidal in vivo activity of EPI has been reported.

  5. Intestinal Schistosomiasis among Primary Schoolchildren in Two On-Shore Communities in Rorya District, Northwestern Tanzania: Prevalence, Intensity of Infection and Associated Risk Factors

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    David Z. Munisi

    2016-01-01

    Full Text Available In Tanzania, Schistosoma mansoni is of great public health importance. Understanding the prevalence and infection intensity is important for targeted, evidence-based control strategies. This study aimed at studying the prevalence, intensity, and risk factors of S. mansoni among schoolchildren in the study area. A cross-sectional study was conducted in Busanga and Kibuyi villages. Sampled 513 schoolchildren provided stool specimens which were examined using kato-katz method. Pretested questionnaire was used to collect sociodemographic data and associated risk factors. The prevalence of S. mansoni infection was 84.01%, with geometric mean egg intensity of 167.13 (95% CI: 147.19–189.79 eggs per gram of stool (epg. Other parasites detected were Ascaris lumbricoides (1.4% and hookworms (1.4%. The geometric mean infection intensity in Busanga and Kibuyi were 203.70 (95% CI: 169.67–244.56 and 135.98 (95% CI: 114.33–161.73 epg, respectively. Light, moderate, and heavy infection intensities were 34.11%, 39.91%, and 25.99%, respectively. Village of residence, parent’s level of education, toilet use, and treatment history were predictors of infection. The high prevalence and infection intensity in this study were associated with village, parent’s level of education, inconsistent toilet use, and treatment history. To control the disease among at-risk groups, these factors need to be considered in designing integrated schistosomiasis control interventions.

  6. Schistosoma mansoni Egg, Adult Male and Female Comparative Gene Expression Analysis and Identification of Novel Genes by RNA-Seq

    Science.gov (United States)

    Anderson, Letícia; Amaral, Murilo S.; Beckedorff, Felipe; Silva, Lucas F.; Dazzani, Bianca; Oliveira, Katia C.; Almeida, Giulliana T.; Gomes, Monete R.; Pires, David S.; Setubal, João C.; DeMarco, Ricardo; Verjovski-Almeida, Sergio

    2015-01-01

    Background Schistosomiasis is one of the most prevalent parasitic diseases worldwide and is a public health problem. Schistosoma mansoni is the most widespread species responsible for schistosomiasis in the Americas, Middle East and Africa. Adult female worms (mated to males) release eggs in the hepatic portal vasculature and are the principal cause of morbidity. Comparative separate transcriptomes of female and male adult worms were previously assessed with using microarrays and Serial Analysis of Gene Expression (SAGE), thus limiting the possibility of finding novel genes. Moreover, the egg transcriptome was analyzed only once with limited bacterially cloned cDNA libraries. Methodology/Principal findings To compare the gene expression of S. mansoni eggs, females, and males, we performed RNA-Seq on these three parasite forms using 454/Roche technology and reconstructed the transcriptome using Trinity de novo assembly. The resulting contigs were mapped to the genome and were cross-referenced with predicted Smp genes and H3K4me3 ChIP-Seq public data. For the first time, we obtained separate, unbiased gene expression profiles for S. mansoni eggs and female and male adult worms, identifying enriched biological processes and specific enriched functions for each of the three parasite forms. Transcripts with no match to predicted genes were analyzed for their protein-coding potential and the presence of an encoded conserved protein domain. A set of 232 novel protein-coding genes with putative functions related to reproduction, metabolism, and cell biogenesis was detected, which contributes to the understanding of parasite biology. Conclusions/Significance Large-scale RNA-Seq analysis using de novo assembly associated with genome-wide information for histone marks in the vicinity of gene models constitutes a new approach to transcriptome analysis that has not yet been explored in schistosomes. Importantly, all data have been consolidated into a UCSC Genome Browser search

  7. The diterpenoid 7-keto-sempervirol, derived from Lycium chinense, displays anthelmintic activity against both Schistosoma mansoni and Fasciola hepatica.

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    Jennifer Edwards

    2015-03-01

    Full Text Available BACKGROUND: Two platyhelminths of biomedical and commercial significance are Schistosoma mansoni (blood fluke and Fasciola hepatica (liver fluke. These related trematodes are responsible for the chronic neglected tropical diseases schistosomiasis and fascioliasis, respectively. As no vaccine is currently available for anti-flukicidal immunoprophylaxis, current treatment is mediated by mono-chemical chemotherapy in the form of mass drug administration (MDA (praziquantel for schistosomiasis or drenching (triclabendazole for fascioliasis programmes. This overreliance on single chemotherapeutic classes has dramatically limited the number of novel chemical entities entering anthelmintic drug discovery pipelines, raising significant concerns for the future of sustainable blood and liver fluke control. METHODOLOGY/ PRINCIPLE FINDINGS: Here we demonstrate that 7-keto-sempervirol, a diterpenoid isolated from Lycium chinense, has dual anthelmintic activity against related S. mansoni and F. hepatica trematodes. Using a microtiter plate-based helminth fluorescent bioassay (HFB, this activity is specific (Therapeutic index = 4.2, when compared to HepG2 cell lines and moderately potent (LD50 = 19.1 μM against S. mansoni schistosomula cultured in vitro. This anti-schistosomula effect translates into activity against both adult male and female schistosomes cultured in vitro where 7-keto-sempervirol negatively affects motility/behaviour, surface architecture (inducing tegumental holes, tubercle swelling and spine loss/shortening, oviposition rates and egg morphology. As assessed by the HFB and microscopic phenotypic scoring matrices, 7-keto-sempervirol also effectively kills in vitro cultured F. hepatica newly excysted juveniles (NEJs, LD50 = 17.7 μM. Scanning electron microscopy (SEM evaluation of adult F. hepatica liver flukes co-cultured in vitro with 7-keto-sempervirol additionally demonstrates phenotypic abnormalities including breaches in tegumental

  8. Antiparasitic activity of menadione (vitamin K3) against Schistosoma mansoni in BABL/c mice.

    Science.gov (United States)

    Kapadia, Govind J; Soares, Ingrid A O; Rao, G Subba; Badoco, Fernanda R; Furtado, Ricardo A; Correa, Mariana B; Tavares, Denise C; Cunha, Wilson R; Magalhães, Lizandra G

    2017-03-01

    Schistosomiasis is one of the neglected tropical diseases affecting nearly quarter of a billion people in economically challenged tropical and subtropical countries of the world. Praziquantel (PZQ) is the only drug currently available to treat this parasitic disease in spite being ineffective against juvenile worms and concerns about developing resistance to treat reinfections. Our earlier in vitro viability studies demonstrated significant antiparasitic activity of menadione (MEN) (vitamin K3) against Schistosoma mansoni adult worms. To gain insight into plausible mechanism of antischistosomal activity of MEN, its effect on superoxide anion levels in adult worms were studied in vitro which showed significant increases in both female and male worms. Further confirmation of the deleterious morphological changes in their teguments and organelles were obtained by ultrastructural analysis. Genotoxic and cytotoxic studies in male Swiss mice indicated that MEN was well tolerated at the oral dose of 500mg/kg using the criteria of MNPCE frequency and PCE/RBC ratio in the bone marrow of infected animals. The in vivo antiparasitic activity of MEN was conducted in female BALB/c mice infected with S. mansoni and significant reductions (P<0.001) in total worm burden were observed at single oral doses of 40 and 400mg/kg (48.57 and 61.90%, respectively). Additionally, MEN significantly reduced (P<0.001) the number of eggs in the liver of infected mice by 53.57 and 58.76%, respectively. Similarly, histological analysis of the livers showed a significant reduction (P<0.001) in the diameter of the granulomas. Since MEN is already in use globally as an over-the-counter drug for a variety of common ailments and a dietary supplement with a safety record in par with similar products when used in recommended doses, the above antiparasitic results which compare reasonably well with PZQ, make a compelling case for considering MEN to treat S. mansoni infection in humans. Copyright © 2016

  9. Epidemiological survey on schistosomiasis caused by Schistosoma ...

    African Journals Online (AJOL)

    SARAH

    2015-06-30

    Jun 30, 2015 ... haematobium and Schistosoma mansoni in primary schools in the Sub-Division of Taïbong-Dziguilao, Cameroon. 8397 ... and stool tests. The examination of urinary sediment and stool samples under the microscope revealed a prevalence of .... education of the population and environmental remediation ...

  10. Schistosomiasis in european travelers and migrants

    DEFF Research Database (Denmark)

    Lingscheid, Tilman; Kurth, Florian; Clerinx, Jan

    2017-01-01

    non-European immigrants. Overall, only 18.6% of travelers had received pretravel advice; 95% of infections were acquired in the African region. On species level, Schistosoma mansoni was identified in 570 (39%) and Schistosoma haematobium in 318 (22%) cases; 57.5% of patients were symptomatic. Acute...

  11. Potential of Sentinel Satellites for Schistosomiasis Monitoring

    Science.gov (United States)

    Li, C.-R.; Tang, L.-L.; Niu, H.-B.; Zhou, X.-N.; Liu, Z.-Y.; Ma, L.-L.; Zhou, Y.-S.

    2012-04-01

    Schistosomiasis is a parasitic disease that menaces human health. In terms of impact this disease is second only to malaria as the most devastating parasitic disease. Oncomelania hupensis is the unique intermediate host of Schistosoma, and hence monitoring and controlling of the number of oncomelania is key to reduce the risk of schistosomiasis transmission. Remote sensing technology can real-timely access the large-scale environmental factors related to oncomelania breeding and reproduction, such as temperature, moisture, vegetation, soil, and rainfall, and can also provide the efficient information to determine the location, area, and spread tendency of oncomelania. Many studies show that the correlation coefficient between oncomelania densities and remote sensing environmental factors depends largely on suitable and high quality remote sensing data used in retrieve environmental factors. Research achievements on retrieving environmental factors (which are related to the living, multiplying and transmission of oncomelania) by multi-source remote data are shown firstly, including: (a) Vegetation information (e.g., Modified Soil-Adjusted Vegetation Index, Normalized Difference Moisture Index, Fractional Vegetation Cover) extracted from optical remote sensing data, such as Landsat TM, HJ-1A/HSI image; (b) Surface temperature retrieval from Thermal Infrared (TIR) and passive-microwave remote sensing data; (c) Water region, soil moisture, forest height retrieval from synthetic aperture radar data, such as Envisat SAR, DLR's ESAR image. Base on which, the requirements of environmental factor accuracy for schistosomiasis monitoring will be analyzed and summarized. Our work on applying remote sensing technique to schistosomiasis monitoring is then presented. The fuzzy information theory is employed to analyze the sensitivity and feasibility relation between oncomelania densities and environmental factors. Then a mechanism model of predicting oncomelania distribution and

  12. Application of an ELISA test using Schistosoma bovis adult worm antigens in travellers and immigrants from a schistosomiasis endemic area and its correlation with clinical findings.

    Science.gov (United States)

    Pardo, Javier; Arellano, Jose Luis Pérez; López-Vélez, Rogelio; Carranza, Cristina; Cordero, Miguel; Muro, Antoio

    2007-01-01

    We have recently evaluated an ELISA for the diagnosis of human schistosomiasis using S. bovis adult worm antigens (AWA Sb), showing a sensitivity of 94% and a specificity of 97% for patients diagnosed by egg detection. Nevertheless, the comparison of this AWA Sb ELISA with direct parasitological findings as the gold standard could introduce a selection bias, due to the well-known lack of sensitivity of direct methods in the detection of acute schistosomiasis and of low burden infections. The objective of the present work is to compare it with parasitological methods and commercial indirect haemagglutination test using S. mansoni antigens (WA Sm IHA) in 254 immigrants and travellers with different clinical settings; in addition, to find specific bands in the EITB of different phases of schistosomiasis. The AWA Sb ELISA showed 72% of seropositivity in patients with Katayama fever, while patients with eosinophilia and genito-urinary complaints showed 27% and 93%, respectively. The diagnosis yield was globally higher than direct egg detection or WA Sm IHA test with regard to the clinical setting. Finally, the utilization of EITB with S. bovis AWA permits the confirmation of diagnosis in chronic and acute phases of the disease.

  13. Utility of Schistosoma bovis adult worm antigens for diagnosis of human schistosomiasis by enzyme-linked immunosorbent assay and electroimmunotransfer blot techniques.

    Science.gov (United States)

    Pardo, J; Carranza, C; Turrientes, M C; Pérez Arellano, J L; López Vélez, R; Ramajo, V; Muro, A

    2004-11-01

    Immunodiagnostic methods based on the detection of antibodies continue to be the most effective and practical methods for the diagnosis of imported schistosomiasis. Schistosoma bovis is a species whose final natural hosts are bovines, ovines, caprines, and small wild ruminants. Different studies have demonstrated the analogies existing between S. bovis and other Schistosoma species which affect humans. The objective of this work was to evaluate the utility of S. bovis adult worm antigens (AWA) for the diagnosis of imported human schistosomiasis by enzyme-linked immunosorbent assay (ELISA) and electroimmunotransfer blotting (EITB) techniques. By detecting eggs, the ELISA for S. bovis AWA was able to definitively detect imported cases with a sensitivity of 94%. The specificity of the ELISA for S. bovis AWA was 97%. There were no differences between the results of the S. bovis AWA ELISA for patients infected with Schistosoma mansoni and those infected with Schistosoma haematobium. The EITB technique showed bands of 85, 37, and 20 kDa, which are characteristic of infections with Schistosoma spp. Specific bands to indicate infection by different species of Schistosoma have not been detected. The combined use of the ELISA for S. bovis AWA and EITB increased the global sensitivity of the study to 97%. Our findings suggest that the ELISA for S. bovis AWA is a useful test for the immunodiagnosis of imported schistosomiasis and that EITB for detecting S. bovis AWA permits the confirmation of diagnosis when the ELISA for S. bovis AWA is positive.

  14. Notes on the use of urine-CCA dipsticks for detection of intestinal schistosomiasis in preschool children.

    Science.gov (United States)

    Navaratnam, A M D; Mutumba-Nakalembe, M J; Stothard, J R; Kabatereine, N B; Fenwick, A; Sousa-Figueiredo, J C

    2012-10-01

    Urine-dipstick diagnostic tests that detect schistosome circulating cathodic antigen (CCA) have the potential to provide more sensitive and rapid testing for intestinal schistosomiasis in field-based surveys; this is especially so when examining preschool children, from whom it may be difficult to obtain consecutive stool samples. To assess the performance of urine dipsticks, 569 preschool children from four villages along the shore of Lake Albert, Uganda, were screened for Schistosoma mansoni by Kato-Katz (K-K) examination of a single stool sample and CCA urine dipsticks. The prevalence of infection was 32.2% by K-K and 40.0% by CCA tests. Sensitivity and specificity were influenced by whether 'trace' results from the CCA test were characterised as positive or negative for infection with S. mansoni; ambiguities around this issue need to be resolved. Nevertheless, the CCA test showed particular promise for routine epidemiological screening in this setting. Copyright © 2012 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.

  15. Schistosomiasis and HIV in rural Zimbabwe: efficacy of treatment of schistosomiasis in individuals with HIV coinfection

    DEFF Research Database (Denmark)

    Kallestrup, Per; Zinyama, Rutendo; Gomo, Exnevia

    2006-01-01

    There is evidence from experimental models that the praziquantel-induced clearance of schistosomiasis is dependent on the host's immune response. Consequently, human immunodeficiency virus (HIV)-related immunodeficiency may impair the effect of praziquantel treatment.......There is evidence from experimental models that the praziquantel-induced clearance of schistosomiasis is dependent on the host's immune response. Consequently, human immunodeficiency virus (HIV)-related immunodeficiency may impair the effect of praziquantel treatment....

  16. Rural tourism as risk factor for the transmission of schistosomiasis in Minas Gerais, Brazil.

    Science.gov (United States)

    Enk, Martin J; Caldeira, Roberta L; Carvalho, Omar S; Schall, Virginia T

    2004-01-01

    Recently, the booming rural tourism in endemic areas of the state of Minas Gerais was identified as a contributing factor in the dissemination of the infection with Schistosoma mansoni. This article presents data from six holiday resorts in a rural district approximately 100 km distant from Belo Horizonte, MG, Brazil, where a possibly new and until now unperceived way of transmission was observed. The infection takes place in swimming pools and little ponds, which are offered to tourists and the local population for fishing and leisure activities. The health authorities of the district reported cases of schistosomiasis among the local population after visiting these sites. As individuals of the non-immune middle class parts of the society of big urban centers also frequent these resorts, infection of these persons cannot be excluded. A malacological survey revealed the presence of molluscs of the species Biomphalaria glabrata and Biomphalaria straminea at the resorts. The snails (B. glabrata) of one resort tested positive for S. mansoni. In order to resolve this complex problem a multidisciplinary approach including health education, sanitation measures, assistance to the local health services, and evolvement of the local political authorities, the local community, the tourism association, and the owners of the leisure resorts is necessary. This evidence emphasizes the urgent need for a participative strategic plan to develop the local tourism in an organized and well-administered way. Only so this important source of income for the region can be ensured on the long term without disseminating the disease and putting the health of the visitors at risk.

  17. Epigenetic changes modulate schistosome egg formation and are a novel target for reducing transmission of schistosomiasis.

    Directory of Open Access Journals (Sweden)

    Vitor Coutinho Carneiro

    2014-05-01

    Full Text Available Treatment and control of schistosomiasis relies on the only available drug, praziquantel, and the search for alternative chemotherapeutic agents is therefore urgent. Egg production is required for the transmission and immunopathology of schistosomiasis and females of S. mansoni lay 300 eggs daily. A large fraction of the total mRNA in the mature female worm encodes one eggshell protein, Smp14. We report that the nuclear receptors SmRXR1 and SmNR1 regulate Smp14 transcription through the recruitment of two histone acetyltransferases (HATs, SmGCN5 and SmCBP1. The treatment of HEK293 cells with histone deacetylase (HDAC inhibitors (NaB or TSA produced an 8-fold activation of the SmRXR1/SmNR1-mediated Smp14 promoter activity. Incubation with synthetic HAT inhibitors, including PU139, significantly impaired the Smp14 promoter activity in these cells. Worm pairs cultivated in the presence of PU139 exhibited limited expression of Smp14 mRNA and protein. ChIP analysis demonstrated chromatin condensation at the Smp14 promoter site in worms treated with PU139. ChIP also revealed the presence of H3K27me3 and the absence of RNA Pol II at the Smp14 promoter region in the PU139-treated worms. Most significantly, the PU139-mediated inhibition of Smp14 expression resulted in a significant number of abnormal eggs as well as defective eggs within the ootype. In addition, scanning electron microscopy revealed structural defects and unformed eggshells, and vitelline cell leakage was apparent. The dsRNAi-targeting of SmGCN5 or SmCBP1 significantly decreased Smp14 transcription and protein synthesis, which compromised the reproductive system of mature female worms, egg-laying and egg morphology. Our data strongly suggest that the inhibition of Smp14 expression targeting SmGCN5 and/or SmCBP1 represents a novel and effective strategy to control S. mansoni egg development.

  18. Schistosoma mansoni: vaccination of mice with 10-krad-irradiated, cryopreserved schistosomules

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, F.A.; Stirewalt, M.A.; Leef, J.L.

    1984-06-01

    Protection against a Schistosoma mansoni cercarial challenge was evaluated in mice immunized with a vaccine composed of 10-krad-irradiated, cryopreserved schistosomules. The level of resistance induced in C57B1/6 or NMRI (CV) mice increased with the number of schistosomules injected. Up to 83% reduction in challenge worm burden was achieved when 5000 schistosomules were injected per mouse. Intramuscular injection of the vaccine was superior to subcutaneous. Multiple immunizations, up to 3 at 4-week intervals, did not increase the resistance induced by a single immunization. A high level of protection developed in as little as 2 weeks and was maintained through at least 12 weeks postimmunization. The vaccine irradiated with 10 krad from either a 60-cobalt or 137-cesium source induced equivalent levels of resistance, and no differences were found in the immunogenicity of vaccines comprised of organisms irradiated as cercariae or as 1- to 3-hr-old schistosomules. These findings are basic to the development of a cryopreserved, live vaccine against schistosomiasis of humans or domestic animals.

  19. Sex-Biased Expression of MicroRNAs in Schistosoma mansoni

    Science.gov (United States)

    Marco, Antonio; Kozomara, Ana; Hui, Jerome H. L.; Emery, Aidan M.; Rollinson, David; Griffiths-Jones, Sam; Ronshaugen, Matthew

    2013-01-01

    Schistosomiasis is an important neglected tropical disease caused by digenean helminth parasites of the genus Schistosoma. Schistosomes are unusual in that they are dioecious and the adult worms live in the blood system. MicroRNAs play crucial roles during gene regulation and are likely to be important in sex differentiation in dioecious species. Here we characterize 112 microRNAs from adult Schistosoma mansoni individuals, including 84 novel microRNA families, and investigate the expression pattern in different sexes. By deep sequencing, we measured the relative expression levels of conserved and newly identified microRNAs between male and female samples. We observed that 13 microRNAs exhibited sex-biased expression, 10 of which are more abundant in females than in males. Sex chromosomes showed a paucity of female-biased genes, as predicted by theoretical evolutionary models. We propose that the recent emergence of separate sexes in Schistosoma had an effect on the chromosomal distribution and evolution of microRNAs, and that microRNAs are likely to participate in the sex differentiation/maintenance process. PMID:24069470

  20. Elimination of Schistosoma mansoni Adult Worms by Rhesus Macaques: Basis for a Therapeutic Vaccine?

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    R Alan Wilson

    2008-09-01

    Full Text Available Among animal models of schistosomiasis, the rhesus macaque is unique in that an infection establishes but egg excretion rapidly diminishes, potentially due to loss of adult worms from the portal system via shunts or death by immune attack.To investigate this, six rhesus macaques were exposed to Schistosoma mansoni cercariae and the infection monitored until portal perfusion at 18 weeks. Despite a wide variation in worm numbers recovered, fecal egg output and circulating antigen levels indicated that a substantial population had established in all animals. Half the macaques had portal hypertension but only one had portacaval shunts, ruling out translocation to the lungs as the reason for loss of adult burden. Many worms had a shrunken and pallid appearance, with degenerative changes in intestines and reproductive organs. Tegument, gut epithelia and muscles appeared cytologically intact but the parenchyma was virtually devoid of content. An early and intense IgG production correlated with low worm burden at perfusion, and blood-feeding worms cultured in the presence of serum from these animals had stunted growth. Using immunoproteomics, gut digestive enzymes, tegument surface hydrolases and antioxidant enzymes were identified as targets of IgG in the high responder animals.It appears that worms starve to death after cessation of blood feeding, as a result of antibody-mediated processes. We suggest that proteins in the three categories above, formulated to trigger the appropriate mechanisms operating in rhesus macaques, would have both prophylactic and therapeutic potential as a human vaccine.

  1. Schistosoma mansoni Polo-like kinases and their function in control of mitosis and parasite reproduction.

    Science.gov (United States)

    Dissous, Colette; Grevelding, Christoph G; Long, Thavy

    2011-06-01

    Polo-like kinases are important regulators of cell cycle progression and mitosis. They constitute a family of conserved serine/threonine kinases which are highly related in their catalytic domains and contain polo boxes involved in protein-protein interactions and subcellular localization. In mammals, five Plks (Plk 1-5) encompass diverse roles in centrosome dynamics, spindle formation, intra S-phase and G2/M checkpoints and DNA damage response. Plk1 is a key positive regulator of mitosis and is overexpressed in various types of cancers. Plk4 is a divergent member of the Plk family, with essential functions in centriole duplication. Homozygous disruption of Plk1 or Plk4 in mice is lethal in embryos. Two Plk members SmPlk1 and SmSak, homologous to Plk1 and Plk4 respectively, are present in the parasitic platyhelminth Schistosoma mansoni. Structural and functional analyses of SmPlk1 have demonstrated its conserved function in the regulation of cell cycle G2/M transition in Xenopus oocytes. The anti-cancer drug BI 2536 (the most potent and selective Plk1 inhibitor) inhibits specifically the catalytic activity of SmPlk1 and induced profound alterations in schistosome gonads, indicating a role of SmPlk1 in parasite gametogenesis and its potential as a novel chemotherapeutic target against schistosomiasis. Functions of SmSak in cell cycle regulation and schistosome gonad development are currently investigated.

  2. Polyethyleneimine (PEI mediated siRNA gene silencing in the Schistosoma mansoni snail host, Biomphalaria glabrata.

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    Matty Knight

    2011-07-01

    Full Text Available An in vivo, non-invasive technique for gene silencing by RNA interference (RNAi in the snail, Biomphalaria glabrata, has been developed using cationic polymer polyethyleneimine (PEI mediated delivery of long double-stranded (ds and small interfering (si RNA. Cellular delivery was evaluated and optimized by using a 'mock' fluorescent siRNA. Subsequently, we used the method to suppress expression of Cathepsin B (CathB with either the corresponding siRNA or dsRNA of this transcript. In addition, the knockdown of peroxiredoxin (Prx at both RNA and protein levels was achieved with the PEI-mediated soaking method. B. glabrata is an important snail host for the transmission of the parasitic digenean platyhelminth, Schistosoma mansoni that causes schistosomiasis in the neotropics. Progress is being made to realize the genome sequence of the snail and to uncover gene expression profiles and cellular pathways that enable the snail to either prevent or sustain an infection. Using PEI complexes, a convenient soaking method has been developed, enabling functional gene knockdown studies with either dsRNA or siRNA. The protocol developed offers a first whole organism method for host-parasite gene function studies needed to identify key mechanisms required for parasite development in the snail host, which ultimately are needed as points for disrupting this parasite mediated disease.

  3. The extracellular release of Schistosoma mansoni HMGB1 nuclear protein is mediated by acetylation

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    Coutinho Carneiro, Vitor; Moraes Maciel, Renata de; Caetano de Abreu da Silva, Isabel; Furtado Madeira da Costa, Rodrigo [Instituto de Bioquimica Medica, Programa de Biotecnologia e Biologia Molecular, Universidade Federal do Rio de Janeiro, CCS, Ilha do Fundao, Rio de Janeiro 21941-590 (Brazil); Neto Paiva, Claudia; Torres Bozza, Marcelo [Departamento de Imunologia, Instituto de Microbiologia Professor Paulo de Goes, Universidade Federal do Rio de Janeiro, CCS, Ilha do Fundao, Rio de Janeiro 21941-590 (Brazil); Rosado Fantappie, Marcelo, E-mail: fantappie@bioqmed.ufrj.br [Instituto de Bioquimica Medica, Programa de Biotecnologia e Biologia Molecular, Universidade Federal do Rio de Janeiro, CCS, Ilha do Fundao, Rio de Janeiro 21941-590 (Brazil)

    2009-12-25

    Schistosoma mansoni HMGB1 (SmHMGB1) was revealed to be a substrate for the parasite histone acetyltransferases SmGCN5 and SmCBP1. We found that full-length SmHMGB1, as well as its HMG-box B (but not HMG-box A) were acetylated in vitro by SmGCN5 and SmCBP1. However, SmCBP1 was able to acetylate both substrates more efficiently than SmGCN5. Interestingly, the removal of the C-terminal acidic tail of SmHMGB1 (SmHMGB1{Delta}C) resulted in increased acetylation of the protein. We showed by mammalian cell transfection assays that SmHMGB1 and SmHMGB1{Delta}C were transported from the nucleus to the cytoplasm after sodium butyrate (NaB) treatment. Importantly, after NaB treatment, SmHMGB1 was also present outside the cell. Together, our data suggest that acetylation of SmHMGB1 plays a role in cellular trafficking, culminating with its secretion to the extracellular milieu. The possible role of SmHMGB1 acetylation in the pathogenesis of schistosomiasis is discussed.

  4. Exposure to Hycanthone alters chromatin structure around specific gene functions and specific repeats in Schistosoma mansoni

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    David eRoquis

    2014-07-01

    Full Text Available Schistosoma mansoni is a parasitic plathyhelminth responsible for intestinal schistosomiasis (or bilharziasis, a disease affecting 67 million people worldwide and causing an important economic burden. The schistosomicides hycanthone, and its later proxy oxamniquine, were widely used for treatments in endemic areas during the 20th century. Recently, the mechanism of action, as well as the genetic origin of a stably and Mendelian inherited resistance for both drugs was elucidated in two strains. However, several observations suggested early on that alternative mechanisms might exist, by which resistance could be induced for these two drugs in sensitive lines of schistosomes. This induced resistance appeared rapidly, within the first generation, but was metastable (not stably inherited. Epigenetic inheritance could explain such a phenomenon and we therefore re-analyzed the historical data with our current knowledge of epigenetics. In addition, we performed new experiments such as ChIP-seq on hycanthone treated worms. We found distinct chromatin structure changes between sensitive worms and induced resistant worms from the same strain. No specific pathway was discovered, but genes in which chromatin structure modification were observed are mostly associated with transport and catabolism, which makes sense in the context of the elimination of the drug. Specific differences were observed in the repetitive compartment of the genome. We finally describe what types of experiments are needed to understand the complexity of heritability that can be based on genetic and/or epigenetic mechanisms for drug resistance in schistosomes.

  5. Morbidity due to Schistosoma mansoni - Entamoeba histolytica coinfection in hamsters (Mesocricetus auratus Morbidade em hamsters (Mesocricetus auratus devido à co-infecção Schistosoma mansoni - Entamoeba histolytica

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    Silvio Santana Dolabella

    2007-04-01

    Full Text Available Data on Schistosoma mansoni-Entamoeba histolytica coinfection are scarce in the literature. In the present study, hamsters that had been infected for 70 days with Schistosoma mansoni (LE strain were inoculated via the portal vein with two strains of trophozoites of Entamoeba histolytica: ICB-EGG (highly virulent and ICB-RPS (non-virulent. The most evident result of coinfection was increased morbidity and mortality, in comparison with either of the infections alone. Histologically, there were no evident signs of interaction between these two infections. The morphological findings of schistosomal granuloma and amoebic abscesses in the liver were similar to those seen in the respective single-infection controls. However, there was severe wasting of the animals with both infections and greater numbers of amoebic lesions in their livers. The results obtained indicated that schistosomiasis aggravates the course of amoebiasis in hamsters.Dados sobre a co-infecção Schistosoma mansoni-Entamoeba histolytica são escassos na literatura. No presente estudo, hamsters com 70 dias de infecção por Schistosoma mansoni (cepa LE foram inoculados com trofozoítos de Entamoeba histolytica, cepa ICB-EGG (virulenta e cepa ICB-RPS (não virulenta, via veia porta. O mais evidente resultado da co-infecção foi o aumento da morbidade e mortalidade, quando comparado com os animais com somente uma das infecções. Histologicamente, não houve sinais evidentes da interação entre as duas infecções. O aspecto morfológico do granuloma esquistossomótico e do abcesso hepático amebiano são similares aos observados nos controles, com somente uma infecção. Entretanto, foi observado que os animais co-infectados apresentavam-se mais debilitados e com maior número de lesões amebianas no fígado. Os resultados obtidos indicam que a esquistossomose agrava o curso da infecção amebiana em hamsters.

  6. Post-splenectomy infections in chronic schistosomiasis as a consequence of bacterial translocation

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    Kedma de Magalhães Lima

    2015-06-01

    Full Text Available INTRODUCTION : Bacterial translocation is the invasion of indigenous intestinal bacteria through the gut mucosa to normally sterile tissues and internal organs. Schistosomiasis may cause alterations in the immune system and damage to the intestines, portal system and mesenteric lymph nodes. This study investigated bacterial translocation and alterations in the intestinal microbiota and mucosa in schistosomiasis and splenectomized mice. METHODS : Forty female 35-day-old Swiss Webster mice were divided into the following four groups with 10 animals each: schistosomotic (ESF, splenectomized schistosomotic (ESEF, splenectomized (EF and control (CF. Infection was achieved by introduction of 50 Schistosoma mansoni (SLM cercariae through the skin. At 125 days after birth, half of the parasitized and unparasitized mice were subjected to splenectomy. Body weights were recorded for one week after splenectomy; then, the mice were euthanized to study bacterial translocation, microbiota composition and intestinal morphometry. RESULTS : We observed significant reductions in the weight increases in the EF, ESF and ESEF groups. There were increases of at least 1,000 CFU of intestinal microbiota bacteria in these groups compared with the CF. The EF, ESF and ESEF mice showed decreases in the heights and areas of villi and the total villus areas (perimeter. We observed frequent co-infections with various bacterial genera. CONCLUSIONS : The ESEF mice showed a higher degree of sepsis. This finding may be associated with a reduction in the immune response associated with the absence of the spleen and a reduction in nutritional absorption strengthened by both of these factors (Schistosoma infection and splenectomy.

  7. Schistosomiasis epidemiology and control: how did we get here and where should we go?

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    RF Sturrock

    2001-09-01

    Full Text Available Although a disease of great antiquity, scientific studies of schistosomiasis began only 150 years ago. The complete life-cycle was not described until just before the First World War, making it possible at last to plan proper community control programmes. Inadequate tools prevented their effective implementation until well after the Second World War when new tools became available, thanks to the newly formed World Health Organization. Molluscicides spearheaded control programmes until the late 1970s but were then replaced by the newly developed, safe drugs still used today. Whatever the method used, the initial goal of eradication was, in the light of experience and cost, gradually replaced by less ambitious targets; first to stop transmission and then to reduce morbidity. The most successful programmes combined several methods to minimise reinfection after chemotherapy. Comparisons between different programmes are difficult without using appropriate, standardised diagnostic techniques and the correct epidemiological measurements. Some examples will be presented, mainly from our studies on Schistosoma mansoni in Kenya. Drug resistance on a scale comparable with malaria has not occurred in schistosomiasis but the likely withdrawal of all drugs except praziquantel leaves its control extremely vulnerable to this potential problem. An effective, affordable vaccine for use in endemic countries is unlikely to be ready for at least 5 years, and developing strategies for its use could take a further decade or more, judging from experience with drugs and molluscicides. In the interim, by analogy with malaria, the most cost-effective approach would the use of drugs combined with other methods to stop transmission, including molluscicides. The cost of molluscicides needs to be reduced and fears allayed about their supposedly adverse ecological effects.

  8. The relationship between water, sanitation and schistosomiasis: a systematic review and meta-analysis.

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    Jack E T Grimes

    2014-12-01

    Full Text Available Access to "safe" water and "adequate" sanitation are emphasized as important measures for schistosomiasis control. Indeed, the schistosomes' lifecycles suggest that their transmission may be reduced through safe water and adequate sanitation. However, the evidence has not previously been compiled in a systematic review.We carried out a systematic review and meta-analysis of studies reporting schistosome infection rates in people who do or do not have access to safe water and adequate sanitation. PubMed, Web of Science, Embase, and the Cochrane Library were searched from inception to 31 December 2013, without restrictions on year of publication or language. Studies' titles and abstracts were screened by two independent assessors. Papers deemed of interest were read in full and appropriate studies included in the meta-analysis. Publication bias was assessed through the visual inspection of funnel plots and through Egger's test. Heterogeneity of datasets within the meta-analysis was quantified using Higgins' I2.Safe water supplies were associated with significantly lower odds of schistosomiasis (odds ratio (OR = 0.53, 95% confidence interval (CI: 0.47-0.61. Adequate sanitation was associated with lower odds of Schistosoma mansoni, (OR = 0.59, 95% CI: 0.47-0.73 and Schistosoma haematobium (OR = 0.69, 95% CI: 0.57-0.84. Included studies were mainly cross-sectional and quality was largely poor.Our systematic review and meta-analysis suggests that increasing access to safe water and adequate sanitation are important measures to reduce the odds of schistosome infection. However, most of the studies were observational and quality was poor. Hence, there is a pressing need for adequately powered cluster randomized trials comparing schistosome infection risk with access to safe water and adequate sanitation, more studies which rigorously define water and sanitation, and new research on the relationships between water, sanitation, hygiene, human

  9. The relationship between water, sanitation and schistosomiasis: a systematic review and meta-analysis.

    Science.gov (United States)

    Grimes, Jack E T; Croll, David; Harrison, Wendy E; Utzinger, Jürg; Freeman, Matthew C; Templeton, Michael R

    2014-12-01

    Access to "safe" water and "adequate" sanitation are emphasized as important measures for schistosomiasis control. Indeed, the schistosomes' lifecycles suggest that their transmission may be reduced through safe water and adequate sanitation. However, the evidence has not previously been compiled in a systematic review. We carried out a systematic review and meta-analysis of studies reporting schistosome infection rates in people who do or do not have access to safe water and adequate sanitation. PubMed, Web of Science, Embase, and the Cochrane Library were searched from inception to 31 December 2013, without restrictions on year of publication or language. Studies' titles and abstracts were screened by two independent assessors. Papers deemed of interest were read in full and appropriate studies included in the meta-analysis. Publication bias was assessed through the visual inspection of funnel plots and through Egger's test. Heterogeneity of datasets within the meta-analysis was quantified using Higgins' I2. Safe water supplies were associated with significantly lower odds of schistosomiasis (odds ratio (OR) = 0.53, 95% confidence interval (CI): 0.47-0.61). Adequate sanitation was associated with lower odds of Schistosoma mansoni, (OR = 0.59, 95% CI: 0.47-0.73) and Schistosoma haematobium (OR = 0.69, 95% CI: 0.57-0.84). Included studies were mainly cross-sectional and quality was largely poor. Our systematic review and meta-analysis suggests that increasing access to safe water and adequate sanitation are important measures to reduce the odds of schistosome infection. However, most of the studies were observational and quality was poor. Hence, there is a pressing need for adequately powered cluster randomized trials comparing schistosome infection risk with access to safe water and adequate sanitation, more studies which rigorously define water and sanitation, and new research on the relationships between water, sanitation, hygiene, human behavior

  10. Prevalence of Schistosomiasis in Wurukum, Makurdi Local ...

    African Journals Online (AJOL)

    prevalence 43.3%), while none of those who use pipe borne and bore-hole water exclusively was infected (p < 0.05). Key words: urinary schistosomiasis, prevalence, water sources. Journal of Medical Laboratory Science Vol.12(2) 2003: 47 - 51 ...

  11. Perceptions and practices on schistosomiasis among communities ...

    African Journals Online (AJOL)

    Abstract: A study on perceptions and practices related to schistosomiasis was conducted among adult people in Ukerewe. Island, in north-western Tanzania where ... Symptoms such as swollen abdomen were associated with witchcraft and taboos such as smelling, seeing or killing a python. Treatment-seeking practices ...

  12. Intestinal Schistosomiasis and the Associated Transmission Factors ...

    African Journals Online (AJOL)

    cost, and simplicity. However, the sensitivity of this method is low particularly in areas of low endemicity, and low- infection intensities (e.g. in young children), and may be affected by day to day .... Schistosomiasis were assessed using logistic regression. ..... Transactions of the Royal Society of Tropical. Medicine and ...

  13. Human Schistosomiasis, And Nigerian Environment And Climate ...

    African Journals Online (AJOL)

    Human schistosomiasis, commonly called “bilharziasis” after a German pathologist, Theodor Bilharz (who first discovered the parasitic agent in Egypt in 1851) is caused by parasitic trematode of the genus, Schistosoma. There are at least 19 varieties of schistosomes, of which five are pathogenic parasites of man: S.

  14. Urinary schistosomiasis and concomitant urinary tract pathogens ...

    African Journals Online (AJOL)

    This study on the prevalence of urinary schistosomiasis and concomitant urinary tract pathogens was carried out between August and December, 1998, among school children in Ibadan North Local Government Area. Terminal urine sample collected from only pupils in classes 3 to 6 for the study were analyzed accordingly ...

  15. community perceptions of schistosomiasis transmission, prevalence ...

    African Journals Online (AJOL)

    91 No. 7 July 2014. COMMUNITY PERCEPTIONS OF SCHISTOSOMIASIS TRANSMISSION, PREVALENCE AND CONTROL IN RELATION ..... yacinth. & hippo grass. W ater H yacinth. & ambatch trees. W ater H yacinth. & reeds. W ater H yacinth h/grass & reeds. H ippo grass. A mbatch tree. A mbatch tree &. R eeds. R eeds.

  16. Prevalence of schistosomiasis infection among primary school ...

    African Journals Online (AJOL)

    A study on the prevalence of schistosomiasis infection was carried out among primary schools pupils in Awgu LGA, Enugu State, Nigeria. The primary schools include; Central Primary School Agbaogugu, Akegbi Primary School, Ogbaku Primary School, Ihe Primary School and Owelli-Court Primary School between ...

  17. coinfection with malaria, hookworm and schistosomiasis among ...

    African Journals Online (AJOL)

    Esem

    Introduction:A school based rapid survey was conducted th th from the 17 to the 19 of May 2011in Zambezi District of. Zambia to determine the prevalence and coinfection rate of malaria, hookworm and schistosomiasis in schoolchildren in other to inform decision maker. Methodology: The study design, sampling methods,.

  18. Schistosoma mansoni and soil-transmitted helminths among preschool-aged children in Chuahit, Dembia district, Northwest Ethiopia: prevalence, intensity of infection and associated risk factors

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    Agersew Alemu

    2016-05-01

    Full Text Available Abstract Background Intestinal schistosomiasis and soil-transmitted helminthiasis are the major public health problems globally. Compared with any other age group, pre-school aged children and school-aged children are the most exposed. There are few studies showing the burden of intestinal schistosomiasis, and soil-transmitted helminthiasis among pre-school aged children in Ethiopia. Hence, this study aimed to assess the prevalence of schistosoma mansoni and soil-transmitted helminths and associated risk factors among preschool aged children of Chuahit and surrounding Kebeles, Northwest Ethiopia. Methods A community based cross sectional study was conducted from February 2 to March 27 2015. Four hundred one preschool-aged children were included in the study by using two stage cluster sampling technique. Pretested structured questionnaire was employed to collected data via face-to-face interview technique. A single stool specimen was collected, and a portion of the sample was processed by Kato Katz method. Results Of the total children, 141 (35.2 % harbored one or more intestinal helminthes. Schistosoma mansoni was found in 45 (11.2 % of preschool age children. Ascaris lumbricoides was the predominant isolate, 77 (19.2 % followed by S. mansoni, 45 (11.2 %. The least parasites isolated were Tania species, 2 (0.5 %. After adjusting for other variables, being mothers who did not have the habit of washing hands after toilet (AOR = 7.3, 95%CI: 2.97–17.95, being occupationally housewife mothers (AOR = 8.9, 95%CI: 2.27–25.4, using protected spring water as a main family source of water (AOR = 3.9, 95%CI: 1.2–12.3 and child habit of not wearing shoe (AOR = 1.91, 95%CI: 1.01–3.64 were significantly associated with high prevalence of soil-transmitted helminthiasis among preschool-age children in Chuahit. Conclusion The current study showed that relatively higher level of STH and S. mansoni among preschool-aged children in

  19. Dual targeting of insulin and venus kinase Receptors of Schistosoma mansoni for novel anti-schistosome therapy.

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    Mathieu Vanderstraete

    Full Text Available BACKGROUND: Chemotherapy of schistosomiasis relies on a single drug, Praziquantel (PZQ and mass-use of this compound has led to emergence of resistant strains of Schistosoma mansoni, therefore pointing out the necessity to find alternative drugs. Through their essential functions in development and metabolism, receptor tyrosine kinases (RTK could represent valuable drug targets for novel anti-schistosome chemotherapies. Taking advantage of the similarity between the catalytic domains of S. mansoni insulin receptors (SmIR1 and SmIR2 and Venus Kinase Receptors (SmVKR1 and SmVKR2, we studied the possibility to fight schistosomes by targeting simultaneously the four receptors with a single drug. METHODOLOGY/PRINCIPAL FINDINGS: Several commercial RTK inhibitors were tested for their potential to inhibit the kinase activities of SmIR1, SmIR2, SmVKR1 and SmVKR2 intracellular domains (ICD expressed in Xenopus oocytes. We measured the inhibitory effect of chemicals on meiosis resumption induced by the active ICD of the schistosome kinases in oocytes. The IR inhibitor, tyrphostin AG1024, was the most potent inhibitory compound towards SmIR and SmVKR kinases. In vitro studies then allowed us to show that AG1024 affected the viability of both schistosomula and adult worms of S. mansoni. At micromolar doses, AG1024 induced apoptosis and caused schistosomula death in a dose-dependent manner. In adult worms, AG1024 provoked alterations of reproductive organs, as observed by confocal laser scanner microscopy. With 5 µM AG1024, parasites were no more feeding and laying eggs, and they died within 48 h with 10 µM. CONCLUSION/SIGNIFICANCE: IRs and VKRs are essential in S. mansoni for key biological processes including glucose uptake, metabolism and reproduction. Our results demonstrate that inhibiting the kinase potential and function of these receptors by a single chemical compound AG1024 at low concentrations, leads to death of schistosomula and adult worms

  20. Dual targeting of insulin and venus kinase Receptors of Schistosoma mansoni for novel anti-schistosome therapy.

    Science.gov (United States)

    Vanderstraete, Mathieu; Gouignard, Nadège; Cailliau, Katia; Morel, Marion; Lancelot, Julien; Bodart, Jean-François; Dissous, Colette

    2013-01-01

    Chemotherapy of schistosomiasis relies on a single drug, Praziquantel (PZQ) and mass-use of this compound has led to emergence of resistant strains of Schistosoma mansoni, therefore pointing out the necessity to find alternative drugs. Through their essential functions in development and metabolism, receptor tyrosine kinases (RTK) could represent valuable drug targets for novel anti-schistosome chemotherapies. Taking advantage of the similarity between the catalytic domains of S. mansoni insulin receptors (SmIR1 and SmIR2) and Venus Kinase Receptors (SmVKR1 and SmVKR2), we studied the possibility to fight schistosomes by targeting simultaneously the four receptors with a single drug. Several commercial RTK inhibitors were tested for their potential to inhibit the kinase activities of SmIR1, SmIR2, SmVKR1 and SmVKR2 intracellular domains (ICD) expressed in Xenopus oocytes. We measured the inhibitory effect of chemicals on meiosis resumption induced by the active ICD of the schistosome kinases in oocytes. The IR inhibitor, tyrphostin AG1024, was the most potent inhibitory compound towards SmIR and SmVKR kinases. In vitro studies then allowed us to show that AG1024 affected the viability of both schistosomula and adult worms of S. mansoni. At micromolar doses, AG1024 induced apoptosis and caused schistosomula death in a dose-dependent manner. In adult worms, AG1024 provoked alterations of reproductive organs, as observed by confocal laser scanner microscopy. With 5 µM AG1024, parasites were no more feeding and laying eggs, and they died within 48 h with 10 µM. IRs and VKRs are essential in S. mansoni for key biological processes including glucose uptake, metabolism and reproduction. Our results demonstrate that inhibiting the kinase potential and function of these receptors by a single chemical compound AG1024 at low concentrations, leads to death of schistosomula and adult worms. Thus, AG1024 represents a valuable hit compound for further design of anti

  1. Dual Targeting of Insulin and Venus Kinase Receptors of Schistosoma mansoni for Novel Anti-schistosome Therapy

    Science.gov (United States)

    Vanderstraete, Mathieu; Gouignard, Nadège; Cailliau, Katia; Morel, Marion; Lancelot, Julien; Bodart, Jean-François; Dissous, Colette

    2013-01-01

    Background Chemotherapy of schistosomiasis relies on a single drug, Praziquantel (PZQ) and mass-use of this compound has led to emergence of resistant strains of Schistosoma mansoni, therefore pointing out the necessity to find alternative drugs. Through their essential functions in development and metabolism, receptor tyrosine kinases (RTK) could represent valuable drug targets for novel anti-schistosome chemotherapies. Taking advantage of the similarity between the catalytic domains of S. mansoni insulin receptors (SmIR1 and SmIR2) and Venus Kinase Receptors (SmVKR1 and SmVKR2), we studied the possibility to fight schistosomes by targeting simultaneously the four receptors with a single drug. Methodology/Principal Findings Several commercial RTK inhibitors were tested for their potential to inhibit the kinase activities of SmIR1, SmIR2, SmVKR1 and SmVKR2 intracellular domains (ICD) expressed in Xenopus oocytes. We measured the inhibitory effect of chemicals on meiosis resumption induced by the active ICD of the schistosome kinases in oocytes. The IR inhibitor, tyrphostin AG1024, was the most potent inhibitory compound towards SmIR and SmVKR kinases. In vitro studies then allowed us to show that AG1024 affected the viability of both schistosomula and adult worms of S. mansoni. At micromolar doses, AG1024 induced apoptosis and caused schistosomula death in a dose-dependent manner. In adult worms, AG1024 provoked alterations of reproductive organs, as observed by confocal laser scanner microscopy. With 5 µM AG1024, parasites were no more feeding and laying eggs, and they died within 48 h with 10 µM. Conclusion/Significance IRs and VKRs are essential in S. mansoni for key biological processes including glucose uptake, metabolism and reproduction. Our results demonstrate that inhibiting the kinase potential and function of these receptors by a single chemical compound AG1024 at low concentrations, leads to death of schistosomula and adult worms. Thus, AG1024

  2. Morbidade da esquistossomose no Brasil: IV. Evolução em pacientes tratados e seus controles Morbidity of schistosomiasis in Brazil: IV. Course in patientes treated and their controls

    Directory of Open Access Journals (Sweden)

    Mozart Lima dos Santos

    1986-03-01

    Full Text Available Um estudo comparativo sobre a evolução da morbidade da esquistossomose mansoni em pacientes tratados e não tratados em uma área endêmica, foi realizado após um e seis anos do tratamento inicial. No primeiro ano após o tratamento verificou-se uma drástica redução do número de ovos de S. mansoni por grama de fezes eliminadas pelos pacientes tratados em relação aos controles e também melhores condições clínicas dos pacientes tratados. Entretanto, ao final de seis anos de observação, embora o número de ovos de S. mansoni eliminados pelos pacientes tratados ainda fosse menor do que no grupo controle ele se aproximava do número inicial antes do tratamento. Em ambos os grupos houve evolução para formas clínicas mais graves, embora com uma certa tendência para maior gravidade no grupo controle. Recomenda-se que o tratamento da população em áreas endêmicas deva ser feito com intervalos de dois a três anos e não se dispensam medidas profiláticas como suprimento de aguá encanada nas casas e educação de base da população.A comparative study on the evolutive morbidity of schistosomiasis mansoni in treated and non-treatd patients in an endemic area was carried-out with evalution of the treatment after one and six years. In the first uear after treatment there was both an improvement in the clinical conditions and a dramatic reduction in the number of S. mansoni eggs eliminated by the treated patients in relation to the controls. However, after six years of observations, although the number of S. mansoni eggs eliminated by the treated patients was still less than in the control group, it was nearly the same number as before treatment. in both treated and non-treated groups there was an increase in the severity of the clinical forms of schistosomiasis, with a certain tenency of greater severity in the control group. Therefore the authors recommend that the specific treatment of the population in endemic area should be done

  3. Schistosoma mansoni Infection Can Jeopardize the Duration of Protective Levels of Antibody Responses to Immunizations against Hepatitis B and Tetanus Toxoid.

    Science.gov (United States)

    Riner, Diana K; Ndombi, Eric M; Carter, Jennifer M; Omondi, Amos; Kittur, Nupur; Kavere, Emmy; Korir, Harrison K; Flaherty, Briana; Karanja, Diana; Colley, Daniel G

    2016-12-01

    Schistosomiasis is a disease of major public health importance in sub-Saharan Africa. Immunoregulation begins early in schistosome infection and is characterized by hyporesponsiveness to parasite and bystander antigens, suggesting that a schistosome infection at the time of immunization could negatively impact the induction of protective vaccine responses. This study examined whether having a Schistosoma mansoni infection at the time of immunization with hepatitis B and tetanus toxoid (TT) vaccines impacts an individual's ability to achieve and maintain protective antibody levels against hepatitis B surface antigen or TT. Adults were recruited from Kisumu Polytechnic College in Western Kenya. At enrollment, participants were screened for schistosomiasis and soil transmitted helminths (STHs) and assigned to groups based on helminth status. The vaccines were then administered and helminth infections treated a week after the first hepatitis B boost. Over an 8 month period, 3 blood specimens were obtained for the evaluation of humoral and cytokine responses to the vaccine antigens and for immunophenotyping. 146 individuals were available for final analysis and 26% were S. mansoni positive (Sm+). Schistosomiasis did not impede the generation of initial minimum protective antibody levels to either hepatitis B or TT vaccines. However, median hepatitis B surface antibody levels were significantly lower in the Sm+ group after the first boost and remained lower, but not significantly lower, following praziquantel (PZQ) treatment and final boost. In addition, 8 months following TT boost and 7 months following PZQ treatment, Sm+ individuals were more likely to have anti-TT antibody levels fall below levels considered optimal for long term protection. IL-5 levels in response to in vitro TT stimulation of whole blood were significantly higher in the Sm+ group at the 8 month time period as well. Individuals with schistosomiasis at the start the immunizations were capable of

  4. Schistosoma mansoni Infection Can Jeopardize the Duration of Protective Levels of Antibody Responses to Immunizations against Hepatitis B and Tetanus Toxoid.

    Directory of Open Access Journals (Sweden)

    Diana K Riner

    2016-12-01

    Full Text Available Schistosomiasis is a disease of major public health importance in sub-Saharan Africa. Immunoregulation begins early in schistosome infection and is characterized by hyporesponsiveness to parasite and bystander antigens, suggesting that a schistosome infection at the time of immunization could negatively impact the induction of protective vaccine responses. This study examined whether having a Schistosoma mansoni infection at the time of immunization with hepatitis B and tetanus toxoid (TT vaccines impacts an individual's ability to achieve and maintain protective antibody levels against hepatitis B surface antigen or TT.Adults were recruited from Kisumu Polytechnic College in Western Kenya. At enrollment, participants were screened for schistosomiasis and soil transmitted helminths (STHs and assigned to groups based on helminth status. The vaccines were then administered and helminth infections treated a week after the first hepatitis B boost. Over an 8 month period, 3 blood specimens were obtained for the evaluation of humoral and cytokine responses to the vaccine antigens and for immunophenotyping.146 individuals were available for final analysis and 26% were S. mansoni positive (Sm+. Schistosomiasis did not impede the generation of initial minimum protective antibody levels to either hepatitis B or TT vaccines. However, median hepatitis B surface antibody levels were significantly lower in the Sm+ group after the first boost and remained lower, but not significantly lower, following praziquantel (PZQ treatment and final boost. In addition, 8 months following TT boost and 7 months following PZQ treatment, Sm+ individuals were more likely to have anti-TT antibody levels fall below levels considered optimal for long term protection. IL-5 levels in response to in vitro TT stimulation of whole blood were significantly higher in the Sm+ group at the 8 month time period as well.Individuals with schistosomiasis at the start the immunizations were

  5. Thermostability of heterophile antibodies from human sera infected with Schistosoma mansoni and geo-helminths: an immuno-metric statistical analysis Termo estabilidade de anticorpos líticos heterófilos de soro de pacientes infectados com Schistosoma mansoni e geo-helmintos: uma análise estatística imuno-métrica

    Directory of Open Access Journals (Sweden)

    Munir Chamone

    2006-06-01

    Full Text Available Antibody in human sera that induces lysis of sheep erythrocytes in hemolytic assay was investigated. The present study showed that the presence in serum of the thermostable cytolytic anti-sheep red blood cells antibodies is dependent on the Schistosoma mansoni infection, and this is more frequent in adults than in children. The thermostable characteristic of hemolysins in normal sera was not dependent on the presence of Ascaris lumbricoides, Trichuris trichiura or hookworm geo-helminths. Further, thermostable complement-activating heterophile antibodies were noticed in children in association with massive number of S. mansoni eggs. The results were obtained by using the z- and the chi-square tests. The z-test allows us to formulate a one-sided alternative, i.e., a tendency of one of the attributes. On the other hand, the chi-square test analyzes the independence between attributes by using a contingency table. Besides the obtained results being interesting in the field of schistosomiasis mansoni, they can provide a new insight into the use of statistics in medical science.Foram investigados anticorpos de soro humano que provocam lise de eritrócitos de carneiro em ensaios hemolíticos. O presente estudo mostra que a presença de anticorpos citolíticos termoestáveis contra hemácias de carneiro é dependente da infecção por Schistosoma mansoni e é mais freqüente em adultos do que em crianças. A característica termo estável da hemolisina em soros normais não é dependente da presença de Ascaris lumbricoides, Trichuris trichiura ou ancilostomídeos. Além disto, anticorpos heterófilos hemolíticos termo estáveis ativadores de complemento foram demonstrados em crianças com associação de altas cargas de ovos de S. mansoni. Os resultados foram obtidos usando-se os testes z- e o qui quadrado. O teste z- nos permite formular uma alternativa "one side", isto é, a tendência de um dos atributos. Por outro lado o teste do qui quadrado

  6. Polarized Th2 like cells, in the absence of Th0 cells, are responsible for lymphocyte produced IL-4 in high IgE-producer schistosomiasis patients

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    Soares-Silveira Alda

    2002-07-01

    Full Text Available Abstract Background Human resistance to re-infection with S. mansoni is correlated with high levels of anti-soluble adult worm antigens (SWAP IgE. Although it has been shown that IL-4 and IL-5 are crucial in establishing IgE responses in vitro, the active in vivo production of these cytokines by T cells, and the degree of polarization of Th2 vs. Th0 in human schistosomiasis is not known. To address this question, we determined the frequency of IL-4 and IFN-γ or IL-5 and IL-2 producing lymphocytes from schistosomiasis patients with high or low levels of IgE anti-SWAP. Results Our analysis showed that high and low IgE-producers responded equally to schistosomiasis antigens as determined by proliferation. Moreover, patients from both groups displayed similar percentages of circulating lymphocytes. However, high IgE-producers had an increased percentage of activated CD4+ T cells as compared to the low IgE-producers. Moreover, intracellular cytokine analysis, after short-term stimulation with anti-CD3/CD28 mAbs, showed that IgE high-producers display an increase in the percentage of T lymphocytes expressing IL-4 and IL-5 as compared to IgE low-responders. A coordinate control of the frequency of IL-4 and IL-5 producing lymphocytes in IgE high, but not IgE low-responders, was observed. Conclusions High IgE phenotype human schistosomiasis patients exhibit a coordinate regulation of IL-4 and IL-5 producing cells and the lymphocyte derived IL-4 comes from true polarized Th2 like cells, in the absence of measurable Th0 cells as measured by co-production of IL-4 and IFN-γ.

  7. The spatial and seasonal distribution of Bulinus truncatus, Bulinus forskalii and Biomphalaria pfeifferi, the intermediate host snails of schistosomiasis, in N’Djamena, Chad

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    Wendelin Moser

    2014-11-01

    Full Text Available There is a paucity of epidemiological and malacological data pertaining to schistosomiasis in Chad. In view of a recently articulated elimination agenda, a deeper understanding of the spatio-temporal distribution of schistosomiasis inter- mediate host snails is pivotal. We conducted cross-sectional malacological surveys during the dry season (April/May 2013 and after the short rainy season (October 2013 in N’Djamena, the capital of Chad. Snails were identified at the genus and species level using morphological keys and molecular DNA barcoding approaches. Those belonging to Bulinus and Biomphalaria were examined for cercarial shedding. Snail habitats were characterised and their predictive potential for the presence of schistosomiasis intermediate host snails explored. Seasonal patterns were studied using geographical information system and kriging in order to interpolate snail abundance data to make predictions at non-sampled locations across N’Djamena. Overall, 413 Bulinus truncatus, 369 Bulinus forskalii and 108 Biomphalaria pfeifferi snails were collected and subjected to cercarial shedding. During the dry season, one Bu. truncatus of 119 snails collected shed Schistosoma spp. cer- cariae (0.84%, while S. mansoni was shed by one of 108 Bi. pfeifferi snails (0.93%. None of the snails collected after the rainy season shed Schistosoma spp. cercariae. The abundance of Bu. truncatus and Bu. forskalii showed an inverse U-shape relationship with the square term of conductivity, i.e. low abundance at the lowest and highest levels of conductivity and high abundance at intermediate levels. Bi. pfeifferi showed a negative, linear association with pH in the dry seasons. It is planned to link these intermediate host snail data to infection data in human populations with the goal to draw a predictive risk map that can be utilised for control and elimination of schistosomiasis in N’Djamena.

  8. Role of Regulatory Immune Responses in the Pathogenesis of Schistosomiasis

    Science.gov (United States)

    2008-07-15

    primarily with the production of eggs by schistosomes. Our previous studies, using a murine model of Schistosoma mansoni infection, demonstrated that...5 Hypothesis and Specific Aims Our previous studies, using a murine model of Schistosoma mansoni infection, demonstrated that...during worm development. To assess this possibility, the regulatory response in infected animals will be disrupted to determine its effect on S

  9. The prolonged use of niclosamide as a molluscicide for the control of Schistosoma mansoni Uso prolongado da niclosamida como moluscicida para o controle do Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Pedro Coura-Filho

    1992-10-01

    Full Text Available Applications of niclosamide at three-monthly intervals were undertaken for 14 years in foci of Biomphalaria glabrata in the water sources of Peri-Peri (Capim Branco, MG. All the residents of the area were submitted to an annual fecal examination (Kato/Katz and those individuals eliminating Schistosoma mansoni eggs were treated with oxamniquine. A malacological survey was undertaken at three-monthly intervals by means of ten scoops with a perforated ladle each ten metres along the two banks of the ditches and streams of the region. Where snails were found, molluscicide was applied by means of dripping or aspersion using a 3 ppm aqueous suspension of niclosamide. Initially, a mean of 14.3% of snails in the region were found to be eliminating cercariae. Following the first four applications of molluscicide, this was reduced to 0.0% and maintained at about 1.5% throughout the program. Thus, there was a continued possibility of schistosomiasis transmission in the area and it was observed that the population of snails reestablished itself within three months of molluscicide application. The results obtained in this study do not encourage the continual use of niclosamide as the only method of control of schistosomiasis.Aplicações trimestrais de niclosamida foram realizadas catorze anos em focos de Biomphalaria glabrata nas coleções hídricas de Peri-Peri, (Capim Branco, MG. Anualmente, os residentes da área eram submetidos a um exame coproscópio (Kato-Katz e os que eliminavam ovos de Schistosoma mansoni nas fezes eram tratados com oxarnniquine. O levantamento malacológico trimestral foi realizado através de dez conchadas a cada dez metros nas duas margens das valas e córregos da região. Onde eram encontrados caramujos aplicava-se o moluscicida pela técnica de gotejamento ou aspersão de suspensão aquosa da niclosamida a 3 ppm. O índice médio de caramujos eliminando cercarias na região era de 14,3%. Após as quatro primeiras aplica

  10. The influence of the regional basic diet from northeast Brazil on health and nutritional conditions of mice infected with Schistosoma mansoni

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    Eridan M. Coutinho

    1992-03-01

    Full Text Available Protein nutritionalstatus indicators were studied in weanling albino Swiss mice infected with S. mansoni andfed the Regional Basic Diet (RBDfrom Northeast Brazil, a multideficient diet of low-protein content. Each mouse was infected percutaneously with 80 cercariae. The experiment lasted 63 days. The growth curve, food consumption, protein intake, weight gain, Protein Efficiency Ratio (PER and Net Protein Ratio (NPR were the parameters investigated. RBD-fed mice showed a marked weight loss, a lower food and protein intake, a slower body weight gain and lower rates of food protein utilization when compared to casein-fed animals. Differences between infected and non-infected mice were not consistent. The present results suggest that the effects of RBD-induced malnutrition on health and nutritional conditions of the mice are more severe than those of Manson's schistosomiasis, in the initial phase of the disease.

  11. Single versus double dose praziquantel comparison on efficacy and Schistosoma mansoni re-infection in preschool-age children in Uganda

    DEFF Research Database (Denmark)

    Nalugwa, Allen; Nuwaha, Fred; Tukahebwa, Edridah Muheki

    2015-01-01

    (PZQ) treatment on cure rates (CRs), egg reduction rates (ERRs) and re-infection rates 8 months later, in children aged 1-5 years living along Lake Victoria, Uganda. METHODOLOGY/PRINCIPAL FINDINGS: Infected children (n= 1017) were randomized to receive either a single or double dose of PZQ. Initially......BACKGROUND: Schistosoma mansoni infection is proven to be a major health problem of preschool-age children in sub-Saharan Africa, yet this age category is not part of the schistosomiasis control program. The objective of this study was to compare the impact of single and double dose praziquantel......, abdominal pain and bloody diarrhea. Overall re-infection rate 8 months post treatment was 44.5%. CONCLUSIONS: PZQ is efficacious and relatively safe to use in preschool-age children but there is still an unmet need to improve its formulation to suit small children. Two PZQ doses lead to significant...

  12. Production of Shistosoma mansoni cercariae by Biomphalaria glabrata from a focus in Belo Horizonte, Minas Gerais Produção de cercárias de Schistosoma mansoni por Biomphalaria glabrata de foco em Belo Horizonte, Minas Gerais

    Directory of Open Access Journals (Sweden)

    Cecília Pereira de Souza

    1994-12-01

    Full Text Available The snail density, levels of infection and the monthly production of Schistosoma mansoni cercariae by Biomphalaria glabrata were determined in a focus of Barreiro de Baixo (Belo Horizonte, MG, Brazil. During a period of 38 months (1984 to 1987 5,366 snails were collected of which 324 (6.03% were infected with S. mansoni. The total number of cercariae shed was 5,667,312. Each snail shed an average of 17,422 cercariae during the time that it was under study in the laboratory. The greatest longevity of infected snails was 218 days. Natural cure was observed in 42 (12.9% of the infected specimens about 130 days after collection. The average snail density in the focus during the period of study was 16.3 snails per scoop. The shedding of cercariae by snails collected from the field was compared with laboratory bred specimens infected in mass with the LE strain of S. mansoni from Belo Horizonte. The laboratory infected snails shed an average of 6,061 cercariae each, a value 2.8 times less than the field specimens due to a shorter life span. The prevalence of schistosomiasis in the focus was 14.3%.A densidade planorbídica, as taxas de infecção e a produção mensal de cercárias de Schistosoma mansoni por Biomphalaria glabrata, foram determinadas em foco do Barreiro de Baixo (Belo Horizonte MG, Brasil. Durante 38 meses, de 1984 a 1987, foram capturados 5.366 moluscos dentre os quais 324 (6,03% estavam infectados com o S. mansoni. O total de cercárias eliminadas foi de 5.667.312. Cada molusco eliminou em média 17.422 cercárias durante sua permanência no laboratório. A maior longevidade dos moluscos infectados foi de 218 dias. Foi observada a cura natural de 42 (12,9% dos exemplares infectados, após cerca de 130 dias de captura. A densidade planorbídica média, no foco durante esse período foi de 16,3 moluscos por conchada. A eliminação de cercárias pelos moluscos do campo foi comparada com a de exemplares criados no laboratório, infectados

  13. Studies on the molluscicidal activity of Agave angustifolia and Pittosporum tobira on schistosomiasis transmitting snails.

    Science.gov (United States)

    Ibrahim, Abdalla M; Abdel-Gawad, Mahfouz M; El-Nahas, Hanan A; Osman, Nadia S

    2015-04-01

    In the search for new molluscicidal plants for controlling the snail vectors of schistosomiasis, laboratory evaluation was made to assess the molluscicidal activity of Agave angustifolia and Pittosporum tobira plants against Biomphalaria alexandrina snails. Results indicated that both plants have promising molluscicidal activity as the LC90 of the dry powder of both plants was 120 ppm. Both plants showed marked cercaricidal and miracidicidal potencies against S. mansoni larvae. The LC90 of both plants (120 ppm) killed most B. alexandrina eggs within 24 h of exposure. The sub-lethal concentrations of both plants markedly suppressed the survival rate of B. alexandrina snails and the mortality increased with increasing the concentrations and the exposure period up to 10 successive weeks. The accumulative toxic effect of these concentrations was continuous during the recovery period. Also, the reproductive rates of exposed snails were greatly affected even through the recovery period. This depression in reproductive ability of snails was accompanied by histological damage in the hermaphrodite glands of exposed snails. Meanwhile, the growth of snails was estimated weekly and it showed great inhibition in exposed snails comparing with the control ones.

  14. Autotransplant of spleen tissue in children with schistosomiasis: evaluation of splenic function after splenosis.

    Science.gov (United States)

    Brandt, C T; Maciel, D T; Caneca, O A; Castro, C M; Araújo, L B

    2001-01-01

    Autotransplantation of spleen tissue has been done, in the past ten years, in children with schistosomiasis mansoni with bleeding varices. The purposes of this investigation were: (1) to study the morphology and function of the remnant spleen tissue; (2) to quantify the production of tuftsin; and (3) to assess the immune response to pneumococcal vaccine of these patients. Twenty three children, who underwent splenectomy and autologous implantation of spleen tissue into the greater omentum were included in this investigation. The average postoperative follow-up is five years. Splenosis was proved by colloid liver-spleen scans. Search for Howell-Jolly bodies assessed the filtration function. Tuftsin and the titer of pneumococcal antibodies were quantified by ELISA. Splenosis was evident in all children; however, it was insufficient in two. Howell-Jolly bodies were found only in these two patients. The mean tuftsin serum concentration (335.0 +/- 29.8 ng/ml) was inside the normal range. The immune response to pneumococcal vaccination was adequate in 15 patients; intermediate in four; and inadequate in four. From the results the following conclusions can be drawn: splenosis was efficient in maintaining the filtration splenic function in more than 90% and produced tuftsin inside the range of normality. It also provided the immunologic splenic response to pneumococcal vaccination in 65% of the patients of this series.

  15. Autotransplant of spleen tissue in children with schistosomiasis: evaluation of splenic function after splenosis

    Directory of Open Access Journals (Sweden)

    Carlos Teixeira Brandt

    2001-09-01

    Full Text Available Autotransplantation of spleen tissue has been done, in the past ten years, in children with schistosomiasis mansoni with bleeding varices. The purposes of this investigation were: (1 to study the morphology and function of the remnant spleen tissue; (2 to quantify the production of tuftsin; and (3 to assess the immune response to pneomococcal vaccine of these patients. Twenty three children, who underwent splenectomy and autologous implantation of spleen tissue into the greater omentum were included in this investigation. The average postoperative follow-up is five years. Splenosis was proved by colloid liver-spleen scans. Search for Howell-Jolly bodies assessed the filtration function. Tuftsin and the titer of pneumococcal antibodies were quantified by ELISA. Splenosis was evident in all children; however, it was insufficient in two. Howell-Jolly bodies were found only in these two patients. The mean tuftsin serum concentration (335.0 ± 29.8 ng/ml was inside the normal range. The immune response to pneumococcal vaccination was adequate in 15 patients; intermediate in four; and inadequate in four. From the results the following conclusions can be drawn: splenosis was efficient in maintaining the filtration splenic function in more than 90% and produced tuftsin inside the range of normality. It also provided the immunologic splenic response to pneumococcal vaccination in 65% of the patients of this series.

  16. The outcome of acute schistosomiasis infection in adult mice with postnatal exposure to maternal malnutrition

    Directory of Open Access Journals (Sweden)

    Christiane Leal Corrêa

    2011-08-01

    Full Text Available Maternal malnutrition during the lactation period in early development may have long-term programming effects on adult offspring. We evaluated the combined effects of parasitological behaviour and histopathological features and malnutrition during lactation. Lactating mice and their pups were divided into a control group (fed a normal diet of 23% protein, a protein-restricted group (PR (fed a diet containing 8% protein and a caloric-restricted group (CR (fed according to the PR group intake. At the age of 60 days, the offspring were infected with Schistosoma mansoni cercariae and killed at nine weeks post-infection. Food intake, body and liver masses, leptinaemia, corticosteronaemia, collagen morphometry and neogenesis and the cellular composition of liver granulomas were studied. PR offspring showed reduced weight gain and hypophagia, whereas CR offspring became overweight and developed hyperphagia. The pre-patent period was longer (45 days in both programmed offspring as compared to controls (40 days. The PR-infected group had higher faecal and intestinal egg output and increased liver damage. The CR-infected group showed a lower number of liver granulomas, increased collagen neogenesis and a higher frequency of binucleate hepatocytes, suggesting a better modulation of the inflammatory response and increased liver regeneration. Taken together, our findings suggest that neonatal malnutrition of offspring during lactation affects the outcome of schistosomiasis in mice.

  17. Systematic Review and Meta-analysis of the Impact of Chemical-Based Mollusciciding for Control of Schistosoma mansoni and S. haematobium Transmission

    Science.gov (United States)

    King, Charles H.; Sutherland, Laura J.; Bertsch, David

    2015-01-01

    Background Programs for schistosomiasis control are advancing worldwide, with many benefits noted in terms of disease reduction. Yet risk of reinfection and recurrent disease remain, even in areas with high treatment coverage. In the search for means to better prevent new Schistosoma infections, attention has returned to an older strategy for transmission control, i.e., chemical mollusciciding, to suppress intermediate host snail species responsible for S. mansoni and S. haematobium transmission. The objective of this systematic review and meta-analysis was to summarize prior experience in molluscicide-based control of Bulinus and Biomphalaria spp. snails, and estimate its impact on local human Schistosoma infection. Methodology/Principal Findings The review was registered at inception with PROSPERO (CRD42013006869). Studies were identified by online database searches and hand searches of private archives. Eligible studies included published or unpublished mollusciciding field trials performed before January 2014 involving host snails for S. mansoni or S. haematobium, with a primary focus on the use of niclosamide. Among 63 included papers, there was large variability in terms of molluscicide dosing, and treatment intervals varied from 3–52 weeks depending on location, water source, and type of application. Among 35 studies reporting on prevalence, random effects meta-analysis indicated that, on average, odds of infection were reduced 77% (OR 0.23, CI95% 0.17, 0.31) during the course of mollusciciding, with increased impact if combined with drug therapy, and progressively greater impact over time. In 17 studies reporting local incidence, risk of new infection was reduced 64% (RR 0.36 CI95% 0.25, 0.5), but additional drug treatment did not appear to influence incidence effects. Conclusion/Significance While there are hurdles to implementing molluscicide control, its impact on local transmission is typically strong, albeit incomplete. Based on past experience

  18. Evaluation of circulating cathodic antigen (CCA) urine-cassette assay as a survey tool for Schistosoma mansoni in different transmission settings within Bugiri District, Uganda.

    Science.gov (United States)

    Adriko, M; Standley, C J; Tinkitina, B; Tukahebwa, E M; Fenwick, A; Fleming, F M; Sousa-Figueiredo, J C; Stothard, J R; Kabatereine, N B

    2014-08-01

    Diagnosis of schistosomiasis at the point-of-care (POC) is a growing topic in neglected tropical disease research. There is a need for diagnostic tests which are affordable, sensitive, specific, user-friendly, rapid, equipment-free and delivered to those who need it, and POC is an important tool for disease mapping and guiding mass deworming. The aim of present study was to evaluate the relative diagnostic performance of two urine-circulating cathodic antigen (CCA) cassette assays, one commercially available and the other in experimental production, against results obtained using the standard Kato-Katz faecal smear method (six thick smears from three consecutive days), as a 'gold-standard', for Schistosoma mansoni infection in different transmission settings in Uganda. Our study was conducted among 500 school children randomly selected across 5 schools within Bugiri district, adjacent to Lake Victoria in Uganda. Considering results from the 469 pupils who provided three stool samples for the six Kato-Katz smears, 293 (76%) children had no infection, 109 (23%) were in the light intensity category, while 42 (9%) and 25 (5%) were in the moderate and heavy intensity categories respectively. Following performance analysis of CCA tests in terms of sensitivity, specificity, negative and positive predictive values, overall performance of the commercially available CCA test was more informative than single Kato-Katz faecal smear microscopy, the current operational field standard for disease mapping. The current CCA assay is therefore a satisfactory method for surveillance of S. mansoni in an area where disease endemicity is declining due to control interventions. With the recent resolution on schistosomiasis elimination by the 65th World Health Assembly, the urine POC CCA test is an attractive tool to augment and perhaps replace the Kato-Katz sampling within ongoing control programmes. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Prevalence of Schistosoma mansoni and soil transmitted helminths ...

    African Journals Online (AJOL)

    western Tanzania. Nyamatongo ... of uptake of preventive chemotherapy, S. mansoni and STH with 95% confidence interval (95% CI) was obtained ... Ethical approval was obtained from the joint Ethical and Review Committee of Bugando Medical.

  20. High prevalence and morbidity of Schistosoma mansoni along the ...

    African Journals Online (AJOL)

    High prevalence and morbidity of Schistosoma mansoni along the Albert Nile in Uganda. Emmanuel I. Odongo-Aginya, Lorenz Grigull, Ulrich Schweigmann, Tom Loroni-Lakwo, Jochem HH Enrich, Bruno Gryseels, Ekkehard Doehring ...

  1. Ruptured ectopic pregnancy associated with tubal schistosomiasis

    Directory of Open Access Journals (Sweden)

    L Sahu

    2013-01-01

    Full Text Available Endemic in major parts of Africa and Middle East, Schistosoma haematobium is a common cause of recurrent urogenital infections and obstetric complications such as spontaneous abortions, ectopic pregnancies, and low birth weight babies. The involvement of fallopian tubes is not rare in endemic areas and may predispose to ectopic pregnancy and infertility. Indian subcontinent is a very lowrisk region for schistosoma infection. Tubal schistosomiasis is not exceptional in endemic zones, but is rarely found in India. The species most often isolated is S. haematobium. Contamination occurs via vascular anastomoses between the bladder and the genital organs. We report a case of tubal schistosomiasis presenting as ruptured ectopic pregnancy discovered on a surgical specimen after salpingectomy.

  2. Change in children's school behavior after mass administration of praziquantel for Schistosoma mansoni infection in endemic areas of western Kenya: A pilot study using the Behavioral Assessment System for Children (BASC-2.

    Directory of Open Access Journals (Sweden)

    Rosemary Musuva

    Full Text Available Schistosomiasis is a parasite-related chronic inflammatory condition that can cause anemia, decreased growth, liver abnormalities, and deficits in cognitive functioning among children.This study used the Behavior Assessment System for Children (BASC-2 to collect data on thirty-six 9-12 year old school-attending children's behavioral profiles in an Schistosoma mansoni-endemic area of western Kenya, before and after treatment with praziquantel for S. mansoni infection. BASC-2 T scores were significantly reduced post-treatment (p < 0.05 for each of the 'negative' behavior categories including externalizing problems (hyperactivity, aggression, and conduct problems that are disruptive in nature, internalizing problems (anxiety, depression, somatization, atypicality, and withdrawal, school problems (academic difficulties, included attention problems and learning problems, and the composite behavioral symptoms index (BSI, signifying improved behavior. While the observed improvement in the 'positive' behavior category of adaptive skills (adaptability, functional communication, social skills, leadership, and study skills was not statistically significant, there were significant improvements in two adaptive skills subcategories: social skills and study skills.Results of this study suggest that children have better school-related behaviors without heavy S. mansoni infection, and that infected children's behaviors, especially disruptive problem behaviors, improve significantly after praziquantel treatment.

  3. Sm21.6 a novel EF-hand family protein member located on the surface of Schistosoma mansoni adult worm that failed to induce protection against challenge infection but reduced liver pathology.

    Science.gov (United States)

    Lopes, Debora O; Paiva, Leonardo F; Martins, Mauricio A; Cardoso, Fernanda C; Rajão, Matheus A; Pinho, Jean M; Caliari, Marcelo V; Correa-Oliveira, Rodrigo; Mello, Samantha M; Leite, Luciana C C; Oliveira, Sergio C

    2009-06-24

    Schistosomiasis continues to be a significant public health problem that affects 200 million people worldwide. This is one of the most important parasitic diseases, and one whose effective control is unlikely in the absence of a vaccine. In this study, we have isolated a cDNA clone encoding the Schistosoma mansoni Sm21.6 protein that has 45% and 44% identity with Sm22.6 and Sj21.7 EF-hand containing antigens, respectively. Confocal microscopy analysis revealed that Sm21.6 is a membrane-associated protein localized on the S. mansoni adult worm. Mouse immunization with rSm21.6 induced a mixed Th1/Th2 cytokine profile and no protection against infection. However, vaccination with rSm21.6 reduced by 28% of liver granuloma numbers, 21% of granuloma area and 34% of fibrosis. Finally, rSm21.6 was recognized by sera from individuals resistant to reinfection compared with patients susceptible to reinfection and this molecule should be further studied as potential biomarker for disease resistance. In conclusion, Sm21.6 is a new tegument protein from S. mansoni that plays an important role in reducing pathology induced by parasite infection.

  4. Intensity of Schistosoma mansoni, hepatitis B, age, and sex predict levels of hepatic periportal thickening/fibrosis (PPT/F): a large-scale community-based study in Ethiopia.

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    Berhe, Nega; Myrvang, Bjørn; Gundersen, Svein G

    2007-12-01

    To elucidate determinants of morbidity in schistosomiasis mansoni, a community-based study was undertaken involving 2,451 subjects (mean age, 18.8 +/- 15.3 [SD] years) from four endemic sites in Ethiopia. Overall prevalence of infection was 65.9%, reported blood in stools was 35.8%, and schistosomal periportal thickening/fibrosis (PPT/F) was 4.6%. Similarly, 43.2% were positive for at least one marker of hepatitis B virus (HBV), 5.3% were HBsAg positive, and 1.3% were anti-hepatitis C virus (HCV) positive. Prevalence of PPT/F increased significantly with increasing community prevalence and intensity of S. mansoni infection. In a multiple logistic regression analysis, intensity of egg excretion, markers of HBV infection, age, and male sex were significantly associated with PPT/F, whereas co-infection with other intestinal helminths was associated with lower odds for PPT/F. HCV was not associated with S. mansoni infection or with schistosomal PPT/F. In conclusion, integrated helminth control targeting school-aged children, who have the highest burden infection, should be used to substantially reduce the risk of periportal fibrosis.

  5. Efficacy and safety of praziquantel in preschool-aged children in an area co-endemic for Schistosoma mansoni and S. haematobium.

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    Jean T Coulibaly

    Full Text Available In sub-Saharan Africa the recommended strategy to control schistosomiasis is preventive chemotherapy. Emphasis is placed on school-aged children, but in high endemicity areas, preschool-aged children are also at risk, and hence might need treatment with praziquantel. Since a pediatric formulation (e.g., syrup is not available outside of Egypt, crushed praziquantel tablets are used, but the efficacy and safety of this treatment regimen is insufficiently studied.We assessed the efficacy and safety of crushed praziquantel tablets among preschool-aged children (<6 years in the Azaguié district, south Côte d'Ivoire, where Schistosoma mansoni and S. haematobium coexist. Using a cross-sectional design, children provided two stool and two urine samples before and 3 weeks after treatment. Crushed praziquantel tablets, mixed with water, were administered at a dose of 40 mg/kg. Adverse events were assessed and graded 4 and 24 hours posttreatment by interviewing mothers/guardians.Overall, 160 preschool-aged children had at least one stool and one urine sample examined with duplicate Kato-Katz thick smears and a point-of-care circulating cathodic antigen (POC-CCA cassette for S. mansoni, and urine filtration for S. haematobium diagnosis before and 3 weeks after praziquantel administration. According to the Kato-Katz and urine filtration results, we found high efficacy against S. mansoni (cure rate (CR, 88.6%; egg reduction rate (ERR, 96.7% and S. haematobium (CR, 88.9%; ERR, 98.0%. POC-CCA revealed considerably lower efficacy against S. mansoni (CR, 53.8%. Treatment was generally well tolerated, but moderately severe adverse events (i.e., body and face inflammation, were observed in four Schistosoma egg-negative children.Crushed praziquantel administered to preschool-aged children at a dose of 40 mg/kg is efficacious against S. mansoni and S. haematobium in a co-endemic setting of Côte d'Ivoire. Further research is required with highly sensitive

  6. Modelling within Host Parasite Dynamics of Schistosomiasis

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    Edward T. Chiyaka

    2010-01-01

    Full Text Available Schistosomiasis infection is characterized by the presence of adult worms in the portal and mesenteric veins of humans as part of a complex migratory cycle initiated by cutaneous penetration of the cercariae shed by infected freshwater snails. The drug praziquantel is not always effective in the treatment against schistosomiasis at larvae stage. However, our simulations show that it is effective against mature worms and eggs. As a result, the study and understanding of immunological responses is key in understanding parasite dynamics. We therefore introduce quantitative interpretations of human immunological responses of the disease to formulate mathematical models for the within-host dynamics of schistosomiasis. We also use numerical simulations to demonstrate that it is the level of T cells that differentiates between either an effective immune response or some degree of infection. These cells are responsible for the differentiation and recruitment of eosinophils that are instrumental in clearing the parasite. From the model analysis, we conclude that control of infection is much attributed to the value of a function f, a measure of the average number of larvae penetrating a susceptible individual having hatched from an egg released by an infected individual. This agrees with evidence that there is a close association between the ecology, the distribution of infection and the disease.

  7. Ultrasonographic Diagnosis of Schistosoma mansoni Eggs in Rectum

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    Fabio G. Rodrigues

    2016-01-01

    Full Text Available Schistosomiasis is a trematode infection endemic in more than 70 countries that affects an estimated 250 million people. We report the case of a 60-year-old healthy female referred for endoscopic ultrasound after rectal examination revealed granular lesions. Ultrasound revealed the presence of deep mucosal nodular lesions with calcified/hyperechoic inclusions. Histologic evaluation has confirmed the final diagnosis of chronic schistosomal colitis. In patients with nonspecific intestinal lesions without a suspected diagnosis of schistosomiasis, endoscopic ultrasound can be enlightening. Schistosomiasis is still an endemic infection in some parts of Brazil and other tropical regions, causing colorectal lesions with unspecific presentation.

  8. Intestinal fibrovascular nodules caused by Schistosoma mansoni infection in Calomys callosus Rengger, 1830 (Rodentia: Cricetidae: a model of concomitant fibrosis and angiogenesis

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    Jane A Lenzi

    2002-10-01

    Full Text Available Human schistosomiasis develops extensive and dense fibrosis in portal space, together with congested new blood vessels. This study demonstrates that Calomys callosus infected with Schistosoma mansoni also develops fibrovascular lesions, which are found in intestinal subserosa. Animals were percutaneously infected with 70 cercariae and necropsied at 42, 45, 55, 80, 90 and 160 days after infection. Intestinal sections were stained for brightfield, polarization microscopy, confocal laser scanning, transmission and scanning electron microscopies. Immunohistological analysis was also performed and some nodules were aseptically collected for cell culture. Numerous intestinal nodules, appearing from 55 up to 160 days after infection, were localized at the interface between external muscular layer and intestinal serosa, consisting of fibrovascular tissue forming a shell about central granuloma(s. Intranodular new vessels were derived from the vasculature of the external vascular layer and were positive for laminin, chondroitin-sulfate, smooth muscle alpha-actin and FVIII-RA. Fibroblastic cells and extracellular matrix components (collagens I, III and VI, fibronectin and tenascin comprised the stroma. Intermixed with the fibroblasts and vessels there were variable number of eosinophils, macrophages and haemorrhagic foci. In conclusion, the nodules constitute an excellent and accessible model to study fibrogenesis and angiogenesis, dependent on S. mansoni eggs. The fibrogenic activity is fibroblastic and not myofibroblastic-dependent. The angiogenesis is so prominent that causes haemorrhagic ascites.

  9. A long-term intake of a protein hydrolysate seems to increase the risk of encephalopathy in mice infected with Schistosoma mansoni

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    Haroldo S Ferreira

    1998-01-01

    Full Text Available Previous investigations showed that Schistosoma mansoni infection aggravates protein malabsorption in undernourished mice and this can be reverted by administration of casein hydrolysate. The present study was undertaken to evaluate the effects of ingestion of casein hydrolysate for long periods. Albino Swiss mice were divided into eight groups. Diets contained 5% (undernourished or 20% (controls casein levels. For each group there were sub-groups ingesting whole or hydrolysed casein for 12 weeks. Infection with S. mansoni developed in half of the animals under each diet. All undernourished mice developed malabsorption. Low albuminemia was detected i