Science.gov

Sample records for schistosomiasis occur independently

  1. Schistosomiasis

    MedlinePlus

    ... the United States. It is common in many tropical and subtropical areas worldwide. Symptoms Symptoms vary with ... schistosomiasis, especially if you have: Traveled to a tropical or subtropical area where the disease is known ...

  2. Schistosomiasis

    PubMed Central

    Tucker, Matthew S.; Karunaratne, Laksiri B.; Lewis, Fred A.; Freitas, Tori C.; Liang, Yung-san

    2014-01-01

    Schistosomiasis is the second most important parasitic disease in the world in terms of public health impact. Globally, it is estimated that the disease affects over 200 million people and is responsible for 200,000 deaths each year. The three major schistosomes infecting humans are Schistosoma mansoni, S. japonicum, and S. haematobium. Much immunological research has focused on schistosomiasis because of the pathological effects of the disease, which include liver fibrosis and bladder dysfunction. This Unit covers a wide range of aspects of maintaining the life cycles of these parasites, including preparation of schistosome egg antigen, maintenance of intermediate snail hosts, infection of the definitive and intermediate hosts, and others. The Unit primariiy focues on S. mansoni, but also includes coverage of S. japonicum and S. haematobium life cycles. PMID:18432750

  3. Interactome disassembly during apoptosis occurs independent of caspase cleavage.

    PubMed

    Scott, Nichollas E; Rogers, Lindsay D; Prudova, Anna; Brown, Nat F; Fortelny, Nikolaus; Overall, Christopher M; Foster, Leonard J

    2017-01-12

    Protein-protein interaction networks (interactomes) define the functionality of all biological systems. In apoptosis, proteolysis by caspases is thought to initiate disassembly of protein complexes and cell death. Here we used a quantitative proteomics approach, protein correlation profiling (PCP), to explore changes in cytoplasmic and mitochondrial interactomes in response to apoptosis initiation as a function of caspase activity. We measured the response to initiation of Fas-mediated apoptosis in 17,991 interactions among 2,779 proteins, comprising the largest dynamic interactome to date. The majority of interactions were unaffected early in apoptosis, but multiple complexes containing known caspase targets were disassembled. Nonetheless, proteome-wide analysis of proteolytic processing by terminal amine isotopic labeling of substrates (TAILS) revealed little correlation between proteolytic and interactome changes. Our findings show that, in apoptosis, significant interactome alterations occur before and independently of caspase activity. Thus, apoptosis initiation includes a tight program of interactome rearrangement, leading to disassembly of relatively few, select complexes. These early interactome alterations occur independently of cleavage of these protein by caspases.

  4. Human Schistosomiasis: Clinical Perspective: Review

    PubMed Central

    Barsoum, Rashad S.; Esmat, Gamal; El-Baz, Tamer

    2013-01-01

    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 Artemether and, possibly

  5. Hepatobiliary Schistosomiasis

    PubMed Central

    Shaker, Yehia; Samy, Nervana; Ashour, Esmat

    2014-01-01

    Schistosomiasis is an ancient parasitic disease that has afflicted Egyptians since the time of the pharaohs. The disease is caused by lodged schistosome eggs in the host liver, evoking an immune response and leading in some patients to the development of hepatic granuloma and fibrosis. Here, we review the epidemiology, immunopathogenesis, and clinical profile of schistosomiasis. This information may aid in the development of more efficacious treatments and improved disease prognosis. PMID:26357627

  6. Cutaneous ectopic schistosomiasis: diagnostic challenge*

    PubMed Central

    Barros, Cláudia Renata Castro do Rêgo; Maia, Daniela Cristina Caetano; dos Santos, Josemir Belo; Medeiros, Camila Carolina Queiroz; de Araújo, Jessica Guido

    2016-01-01

    Cutaneous schistosomiasis is a rare clinical manifestation of schistosomiasis, an infectious and parasitic disease, caused in Brazil by the trematode Schistosoma mansoni. The lesions are due to the deposition of eggs or, rarely, adult worms, usually involving the genital and groin areas. Extra-genital lesions occur mainly on the torso as papules of zosteriform appearance. The case of a patient with ectopic cutaneous schistosomiasis is reported in this article, due to the rarity of its occurrence and its difficult clinical diagnosis. PMID:26982792

  7. Naturally occurring CD4+Foxp3+ regulatory T cells are an essential, IL-10-independent part of the immunoregulatory network in Schistosoma mansoni egg-induced inflammation.

    PubMed

    Baumgart, Martin; Tompkins, Fae; Leng, Jin; Hesse, Matthias

    2006-05-01

    In acute and chronic schistosomiasis, survival of the host requires a carefully balanced immune response against highly immunogenic parasite eggs. We characterized the phenotype, distribution, and functional role of CD4(+)Foxp3(+) naturally occurring regulatory T cells (naTregs) in schistosome egg-induced inflammation. In adoptive transfer experiments and by intracellular staining for Foxp3, we demonstrate significant frequencies of naTregs in hepatic granulomas and draining lymphoid tissues of mice infected with the trematode Schistosoma mansoni. Strikingly, egg-induced inflammation does not change the normal ratio between naTregs and effector CD4(+) T cells at the inflammatory site or in lymphoid organs in acute or chronic disease. However, increasing frequencies of CD103-expressing cells in the naTreg compartment indicate a change in phenotype for naTregs with disease progression. Because CD103 was described recently as an activation marker for naTregs, we speculate that naTregs in chronic schistosomiasis are potentially more suppressive. Furthermore, we found that most naTregs do not contribute to egg-induced IL-4 and IL-10 production. Importantly, depletion of CD25(+) naTregs strongly enhances the frequency of IL-4-producing effector T cells in acute egg-induced inflammation. It does not change clonal expansion of activated CD4(+) T cells. This regulation of egg-induced cytokine production does not require the presence of IL-10. These data demonstrate that naTregs limit egg-induced effector-cytokine production in our model. Our results identify naTregs as an important, IL-10-independent part of the regulatory network in schistosome egg-induced inflammation.

  8. Genitourinary schistosomiasis.

    PubMed

    Al-Ghorab, M M; Smith, D R

    1979-01-01

    Schistosomiasis is a chronic granulomatous disease endemic in the Middle East and Africa, which undermines the function of the genitourinary tract to a serious degree. It is amenable to medical treatment in the early stages but therapy usually is negated by frequent reinfestations. Patients who have complications in the chronic stage of the disease require the level of judicious handling that always taxes the ingenuity and skill of the urologic surgeon.

  9. Hepatic and Intestinal Schistosomiasis: Review

    PubMed Central

    Elbaz, Tamer; Esmat, Gamal

    2013-01-01

    Schistosomiasis is an endemic disease in Egypt caused by the trematode Schistosoma which has different species. Hepatic schistosomiasis represents the best known form of chronic disease with a wide range of clinical manifestations. The pathogenesis of schistosomiasis is related to the host cellular immune response. This leads to granuloma formation and neo angiogenesis with subsequent periportal fibrosis manifested as portal hypertension, splenomegaly and esophageal varices. Intestinal schistosomiasis is another well identified form of chronic schistosomal affection. Egg deposition and granuloma formation eventually leads to acute then chronic schistosomal colitis and is commonly associated with polyp formation. It frequently presents as abdominal pain, diarrhea, tenesmus and anal pain. Definite diagnosis of schistosomiasis disease depends on microscopy and egg identification. Marked progress regarding serologic diagnosis occurred with development of recent PCR techniques that can confirm schistosomal affection at any stage. Many antischistosomal drugs have been described for treatment, praziquantel being the most safe and efficient drug. Still ongoing studies try to develop effective vaccines with identification of many target antigens. Preventive programs are highly needed to control the disease morbidity and to break the cycle of transmission. PMID:25685451

  10. The chronic enteropathogenic disease schistosomiasis.

    PubMed

    Olveda, David U; Olveda, Remigio M; McManus, Donald P; Cai, Pengfei; Chau, Thao N P; Lam, Alfred K; Li, Yuesheng; Harn, Donald A; Vinluan, Marilyn L; Ross, Allen G P

    2014-11-01

    Schistosomiasis is a chronic enteropathogenic disease caused by blood flukes of the genus Schistosoma. The disease afflicts approximately 240 million individuals globally, causing approximately 70 million disability-adjusted life years lost. Chronic infections with morbidity and mortality occur as a result of granuloma formation in the intestine, liver, or in the case of Schistosoma haematobium, the bladder. Various methods are utilized to diagnose and evaluate liver fibrosis due to schistosomiasis. Liver biopsy is still considered the gold standard, but it is invasive. Diagnostic imaging has proven to be an invaluable method in assessing hepatic morbidity in the hospital setting, but has practical limitations in the field. The potential of non-invasive biological markers, serum antibodies, cytokines, and circulating host microRNAs to diagnose hepatic fibrosis is presently undergoing evaluation. This review provides an update on the recent advances made with respect to gastrointestinal disease associated with chronic schistosomiasis.

  11. Human schistosomiasis.

    PubMed

    Colley, Daniel G; Bustinduy, Amaya L; Secor, W Evan; King, Charles H

    2014-06-28

    Human schistosomiasis--or bilharzia--is a parasitic disease caused by trematode flukes of the genus Schistosoma. By conservative estimates, at least 230 million people worldwide are infected with Schistosoma spp. Adult schistosome worms colonise human blood vessels for years, successfully evading the immune system while excreting hundreds to thousands of eggs daily, which must either leave the body in excreta or become trapped in nearby tissues. Trapped eggs induce a distinct immune-mediated granulomatous response that causes local and systemic pathological effects ranging from anaemia, growth stunting, impaired cognition, and decreased physical fitness, to organ-specific effects such as severe hepatosplenism, periportal fibrosis with portal hypertension, and urogenital inflammation and scarring. At present, preventive public health measures in endemic regions consist of treatment once every 1 or 2 years with the isoquinolinone drug, praziquantel, to suppress morbidity. In some locations, elimination of transmission is now the goal; however, more sensitive diagnostics are needed in both the field and clinics, and integrated environmental and health-care management will be needed to ensure elimination.

  12. Drugs for treating urinary schistosomiasis

    PubMed Central

    Kramer, Christine V; Zhang, Fan; Sinclair, David; Olliaro, Piero L

    2014-01-01

    Background Urinary schistosomiasis is caused by an intravascular infection with parasitic Schistosoma haematobium worms. The adult worms typically migrate to the venous plexus of the human bladder and excrete eggs which the infected person passes in their urine. Chronic infection can cause substantial morbidity and long-term complications as the eggs become trapped in human tissues causing inflammation and fibrosis. We summarised evidence of drugs active against the infection. This is new edition of a review first published in 1997. Objectives To evaluate the efficacy and safety of drugs for treating urinary schistosomiasis. Search methods We searched the Cochrane Infectious Diseases Group Specialized Register, MEDLINE, CENTRAL, EMBASE and LILACS and reference lists of articles up to 23 May 2014. Selection criteria Randomized controlled trials (RCTs) of antischistosomal drugs and drug combinations compared to placebo, no intervention, or each other. Data collection and analysis Two researchers independently screened the records, extracted the data and assessed risk of bias. The primary efficacy outcomes were parasitological failure (defined as the continued presence of S. haematobium eggs in the urine at time points greater than one month after treatment), and percent reduction of egg counts from baseline. We presented dichotomous data as risk ratios (RR), and continuous data as mean difference (MD), alongside their 95% confidence intervals (CIs). Where appropriate we combined trials in meta analyses or tables. We assessed the quality of evidence using the GRADE approach. Main results We included 30 RCTs enrolling 8165 participants in this review. Twenty-four trials were conducted in children in sub-Saharan Africa, and 21 trials were over 20 years old. Many studies were assessed as being at unclear risk of bias due to inadequate descriptions of study methods. Praziquantel On average, a single 40 mg/kg dose of praziquantel reduced the proportion of people still

  13. Domain loss has independently occurred multiple times in plant terpene synthase evolution

    PubMed Central

    Hillwig, Matthew L.; Xu, Meimei; Toyomasu, Tomonobu; Tiernan, Mollie S.; Wei, Gao; Cui, Guanghong; Huang, Luqi; Peters, Reuben J.

    2011-01-01

    SUMMARY The extensive family of plant terpene synthases (TPSs) generally has a bi-domain structure, yet phylogenetic analyses consistently indicate that these evolved from larger diterpene synthases. In particular, that duplication of the diterpene synthase genes required for gibberellin phytohormone biosynthesis provided an early predecessor, whose loss of a ~220 amino acid “internal sequence element” (now recognized as the γ domain) gave rise to the precursor of modern mono- and sesqui-TPSs found in all higher plants. Intriguingly, TPSs are conserved by taxonomic relationships rather than function, demonstrating that such functional radiation has occurred both repeatedly and relatively recently, yet phylogenetic analyses assume that “internal/γ” domain loss represents a single evolutionary event. Here we provide evidence that such loss was not a singular event, but rather has occurred multiple times. Specifically, we provide an example of a bi-domain diterpene synthase, from Salvia miltiorrhiza, along with a sesquiterpene synthase from Triticum aestivum (wheat) that is not only closely related to diterpene synthases, but retains the ent-kaurene synthase activity relevant to the ancestral gibberellin metabolic function. Indeed, while the wheat sesquiterpene synthase clearly no longer contains the “internal/γ” domain, it is closely related to rice diterpene synthase genes that retain the ancestral tri-domain structure. Thus, these findings provide examples of key evolutionary intermediates underlying the bi-domain structure observed in the expansive plant TPS gene family, as well as indicating that “internal/γ” domain loss has independently occurred multiple times, highlighting the complex evolutionary history of this important enzymatic family. PMID:21999670

  14. Fruit growth in Arabidopsis occurs via DELLA-dependent and DELLA-independent gibberellin responses.

    PubMed

    Fuentes, Sara; Ljung, Karin; Sorefan, Karim; Alvey, Elizabeth; Harberd, Nicholas P; Østergaard, Lars

    2012-10-01

    Fruit growth and development depend on highly coordinated hormonal activities. The phytohormone gibberellin (GA) promotes growth by inducing degradation of the growth-repressing DELLA proteins; however, the extent to which DELLA proteins contribute to GA-mediated gynoecium and fruit development remains to be clarified. Here, we provide an in-depth characterization of the role of DELLA proteins in Arabidopsis thaliana fruit growth. We show that DELLA proteins are key regulators of reproductive organ size and important for ensuring optimal fertilization. We demonstrate that the seedless fruit growth (parthenocarpy) observed in della mutants can be directly attributed to the constitutive activation of GA signaling. It has been known for >75 years that another hormone, auxin, can induce formation of seedless fruits. Using mutants with complete lack of DELLA activity, we show here that auxin-induced parthenocarpy occurs entirely through GA signaling in Arabidopsis. Finally, we uncover the existence of a DELLA-independent GA response that promotes fruit growth. This response requires GIBBERELLIN-INSENSITIVE DWARF1-mediated GA perception and a functional 26S proteasome and involves the basic helix-loop-helix protein SPATULA as a key component. Taken together, our results describe additional complexities in GA signaling during fruit development, which may be particularly important to optimize the conditions for successful reproduction.

  15. Chemotherapy Studies on Schistosomiasis.

    DTIC Science & Technology

    Schistosoma mansoni, *Chemotherapy, *Prophylaxis, Preventive medicine, Mice, Drugs, Brazil , Laboratory tests, Snails, Cercariae, Tropical medicine, Selection, Parasitology, Schistosomiasis, Chemotherapeutic agents, Medical research

  16. Naturally Occurring β-Nicotinamide Adenine Dinucleotide-Independent Avibacterium paragallinarum Isolate in Peru.

    PubMed

    Falconi-Agapito, Francesca; Saravia, Luis E; Flores-Pérez, Aldo; Fernández-Díaz, Manolo

    2015-06-01

    The β-nicotinamide adenine dinucleotide (NAD) requirement has been considered to be essential for the isolation of the causal agent of infectious coryza, Avibacterium paragallinarum. Nevertheless, NAD-independent reports from South Africa and Mexico dismissed this paradigm. It is now accepted that both NAD-dependent and NAD-independent agents are able to cause infectious coryza and thus belong to the species A. paragallinarum. Here, we report for the first time in Peru a NAD-independent isolate from broiler chickens with typical signs of infectious coryza that have received a trivalent inactivated vaccine against infectious coryza. The isolate was identified based on its morphology, biochemical and serologic tests, and PCR results. Partial 16S rRNA gene sequence analysis confirmed the isolate as A. paragallinarum. There have been no cases of NAD-independent A. paragallinarum isolates reported in South America. Increasing reports around the world highlight not only the need to reconsider the in vitro nutritional requirements of this species for its correct isolation but also the cross-protection conferred by commercial infectious coryza vaccines against NAD-independent isolates.

  17. Schistosomiasis (Bilharzia)

    MedlinePlus

    ... praziquantel. If this were to occur, an alternative drug would be needed as a substitute. To fulfill this need, NIAID-supported researchers are conducting basic research to learn more about certain biochemical pathways that ...

  18. Immunopathogenesis of human schistosomiasis.

    PubMed

    Burke, M L; Jones, M K; Gobert, G N; Li, Y S; Ellis, M K; McManus, D P

    2009-04-01

    Schistosomiasis continues to be a significant cause of parasitic morbidity and mortality worldwide. This review considers the basic features of the pathology and clinical outcomes of hepatointestinal and genitourinary schistosomiasis, presents an overview of the numerous studies on animal models that have clarified many of the immunopathological features, and provides insight into our current understanding of the immunopathogenesis and genetic control of human schistosomiasis. In murine schistosomiasis, pathology is induced by a CD4(+) Th2 driven granulomatous response directed against schistosome eggs lodged in the host liver. The Th2 cytokines IL-4 and IL-13 drive this response, whereas IL-10, IL13Ralpha2, IFN-gamma and a subset of regulatory T-cells act to limit schistosome induced pathology. A variety of cell types including hepatic stellate cells, alternatively activated macrophages and regulatory T-cells have also been implicated in the pathogenesis of schistosomiasis. Current knowledge suggests the immunopathogenic mechanisms underlying human schistosomiasis are likely to be similar. The review also considers the future development of anti-pathology schistosome vaccines. As fibrosis is an important feature of many other diseases such as Crohn's disease and sarcoidosis, a comprehensive understanding of the cellular and molecular mechanisms involved in schistosomiasis may also ultimately contribute to the development an effective disease intervention strategy for other granulofibrotic diseases.

  19. Pattern reorganization occurs independently of cell division during Drosophila wing disc regeneration in situ.

    PubMed

    Díaz-García, Sandra; Baonza, Antonio

    2013-08-06

    One of the most intriguing problems in developmental biology is how an organism can replace missing organs or portions of its body after injury. This capacity, known as regeneration, is conserved across different phyla. The imaginal discs of Drosophila melanogaster provide a particularly well-characterized model for analyzing regeneration. We have developed a unique method to study organ regeneration under physiological conditions using the imaginal discs of Drosophila. Using this method, we revisited different aspects of organ regeneration. The results presented in this report suggest that during the initial stages of regeneration, different processes occur, including wound healing, a temporary loss of markers of cell-fate commitment, and pattern reorganization. We present evidence indicating that all of these processes occur even when cell division has been arrested. Our data also suggested that Wingless is not required during the early stages of disc regeneration.

  20. Pattern reorganization occurs independently of cell division during Drosophila wing disc regeneration in situ

    PubMed Central

    Díaz-García, Sandra; Baonza, Antonio

    2013-01-01

    One of the most intriguing problems in developmental biology is how an organism can replace missing organs or portions of its body after injury. This capacity, known as regeneration, is conserved across different phyla. The imaginal discs of Drosophila melanogaster provide a particularly well-characterized model for analyzing regeneration. We have developed a unique method to study organ regeneration under physiological conditions using the imaginal discs of Drosophila. Using this method, we revisited different aspects of organ regeneration. The results presented in this report suggest that during the initial stages of regeneration, different processes occur, including wound healing, a temporary loss of markers of cell-fate commitment, and pattern reorganization. We present evidence indicating that all of these processes occur even when cell division has been arrested. Our data also suggested that Wingless is not required during the early stages of disc regeneration. PMID:23878228

  1. Rapid bursts of androgen-binding protein (Abp) gene duplication occurred independently in diverse mammals

    PubMed Central

    2008-01-01

    Background The draft mouse (Mus musculus) genome sequence revealed an unexpected proliferation of gene duplicates encoding a family of secretoglobin proteins including the androgen-binding protein (ABP) α, β and γ subunits. Further investigation of 14 α-like (Abpa) and 13 β- or γ-like (Abpbg) undisrupted gene sequences revealed a rich diversity of developmental stage-, sex- and tissue-specific expression. Despite these studies, our understanding of the evolution of this gene family remains incomplete. Questions arise from imperfections in the initial mouse genome assembly and a dearth of information about the gene family structure in other rodents and mammals. Results Here, we interrogate the latest 'finished' mouse (Mus musculus) genome sequence assembly to show that the Abp gene repertoire is, in fact, twice as large as reported previously, with 30 Abpa and 34 Abpbg genes and pseudogenes. All of these have arisen since the last common ancestor with rat (Rattus norvegicus). We then demonstrate, by sequencing homologs from species within the Mus genus, that this burst of gene duplication occurred very recently, within the past seven million years. Finally, we survey Abp orthologs in genomes from across the mammalian clade and show that bursts of Abp gene duplications are not specific to the murid rodents; they also occurred recently in the lagomorph (rabbit, Oryctolagus cuniculus) and ruminant (cattle, Bos taurus) lineages, although not in other mammalian taxa. Conclusion We conclude that Abp genes have undergone repeated bursts of gene duplication and adaptive sequence diversification driven by these genes' participation in chemosensation and/or sexual identification. PMID:18269759

  2. Vaginal chlamydial clearance following primary or secondary infection in mice occurs independently of TNF-α.

    PubMed

    Kamalakaran, Sangamithra; Chaganty, Bharat K R; Gupta, Rishein; Guentzel, M Neal; Chambers, James P; Murthy, Ashlesh K; Arulanandam, Bernard P

    2013-01-01

    The role of TNF-α in chlamydial clearance is uncertain. Antibody-mediated depletion of TNF-α in mice and guinea pigs has been shown not to significantly affect chlamydial clearance, whereas production of TNF-α in addition to IFN-γ from T cells has been shown to correlate with enhanced clearance. The aim of our study is to evaluate the mechanistic role of TNF-α in clearance of primary and secondary chlamydial infection from the genital tract (GT) using C57BL/6 TNF-α deficient (TNF-α(-/-)) and wild type (WT) mice. Chlamydial shedding from the lower GT was evaluated following primary and secondary intravaginal challenge. Also, antibody and antigen specific cytokine responses were analyzed from the infected GT and spleens, and oviduct pathology determined to analyze the role of TNF-α in upper GT pathological sequelae. MHC II(-/-) mice, known to display muted adaptive immune responses and failure to resolve genital chlamydial infections, were used as a negative control. Following both primary and secondary genital chlamydial infection, TNF-α(-/-) mice exhibited elevated granzyme B production, but similar IFN-γ and antibody responses. Importantly, absence of TNF-α did not significantly alter the resolution of infection. However, TNF-α(-/-) mice displayed significantly reduced upper genital tract (UGT) pathology compared to WT mice. This study demonstrates mechanistically that optimal chlamydial clearance following primary and secondary chlamydial genital infection can occur in the complete absence of TNF-α, and considered with the reduction of upper GT pathology in TNF-α(-/-) mice, suggests that targeted induction of anti-chlamydial TNF-α responses by vaccination may be unnecessary, and moreover could be potentially pathogenic.

  3. Vaginal chlamydial clearance following primary or secondary infection in mice occurs independently of TNF-α

    PubMed Central

    Kamalakaran, Sangamithra; Chaganty, Bharat K. R.; Gupta, Rishein; Guentzel, M. Neal; Chambers, James P.; Murthy, Ashlesh K.; Arulanandam, Bernard P.

    2013-01-01

    The role of TNF-α in chlamydial clearance is uncertain. Antibody-mediated depletion of TNF-α in mice and guinea pigs has been shown not to significantly affect chlamydial clearance, whereas production of TNF-α in addition to IFN-γ from T cells has been shown to correlate with enhanced clearance. The aim of our study is to evaluate the mechanistic role of TNF-α in clearance of primary and secondary chlamydial infection from the genital tract (GT) using C57BL/6 TNF-α deficient (TNF-α−/−) and wild type (WT) mice. Chlamydial shedding from the lower GT was evaluated following primary and secondary intravaginal challenge. Also, antibody and antigen specific cytokine responses were analyzed from the infected GT and spleens, and oviduct pathology determined to analyze the role of TNF-α in upper GT pathological sequelae. MHC II−/− mice, known to display muted adaptive immune responses and failure to resolve genital chlamydial infections, were used as a negative control. Following both primary and secondary genital chlamydial infection, TNF-α−/− mice exhibited elevated granzyme B production, but similar IFN-γ and antibody responses. Importantly, absence of TNF-α did not significantly alter the resolution of infection. However, TNF-α−/− mice displayed significantly reduced upper genital tract (UGT) pathology compared to WT mice. This study demonstrates mechanistically that optimal chlamydial clearance following primary and secondary chlamydial genital infection can occur in the complete absence of TNF-α, and considered with the reduction of upper GT pathology in TNF-α−/− mice, suggests that targeted induction of anti-chlamydial TNF-α responses by vaccination may be unnecessary, and moreover could be potentially pathogenic. PMID:23483844

  4. Schistosomiasis in Lake Malawi.

    PubMed

    Cetron, M S; Chitsulo, L; Sullivan, J J; Pilcher, J; Wilson, M; Noh, J; Tsang, V C; Hightower, A W; Addiss, D G

    1996-11-09

    Schistosomiasis is a parasitic infection caused by trematodes. Humans are infected through skin contact with free-swimming cercariae which develop in freshwater snails. Schistosomiasis has been endemic to Malawi for several decades, but the open waters and shores of Lake Malawi have long been thought to be risk-free with regard to schistosomiasis transmission. However, in 1992, two US Peace Corps volunteers developed central nervous system schistosomiasis due to infection with Schistosoma haematobium following recreational water exposure at Cape Maclear on Lake Malawi. In light of these infections, a cross-sectional survey of resident expatriates and visitors to Malawi was subsequently conducted during March-April 1993 to determine the transmission potential and risk for acquiring schistosomiasis in the lake. 305 US citizens and 650 non-US foreign nationals participated in the study. Serological evidence of current or past schistosome infection was identified in 303 subjects. Indeed, seroprevalence was 32% among expatriates whose freshwater exposure was limited to Lake Malawi; S. haematobium antibodies were found in 135 of 141 seropositive specimens. The risk of seropositivity increased with the number of freshwater exposures at Lake Malawi resorts. While many resort areas in the southwestern lake region posed a significant risk, Cape Maclear was the location most strongly associated with seropositivity. Schistosome-infected Bulinus globosus, the snail vector of S. haematobium in Malawi, were found at Cape Maclear and other locations along the lakeshore.

  5. Schistosomiasis-associated kidney disease: A review

    PubMed Central

    da Silva, Geraldo Bezerra; Duarte, Daniella Bezerra; Barros, Elvino José Guardão; Daher, Elizabeth De Francesco

    2013-01-01

    Schistosomiasis is a parasitic disease caused by organisms from the genus Schistosoma. The disease is endemic in tropical areas, where there are currently millions of people living in areas with transmission risk. Schistosomiasis-associated kidney disease is not frequently described in literature. The disease has a chronic evolution, with variable severity. Glomerulonephritis is described in 10-12% in autopsy studies. Proteinuria is reported in 20% of patients with S. mansoni infection. Schistosomal glomerulopathy generally occur in young patients, male, with hepato-splenomegaly. The glomerular lesion in schistosomiasis has an immunological nature. Antigens from the parasite seem to be related to glomerulopathy and have been found in the sera of humans and animals infected by the S. mansoni. Vesical involvement is common in the infection by S. haematobium, a parasitic disease prevalent in African countries. In the S. haematobium infection, hematuria and dysuria can be observed due to inflammation and ulceration in the bladder mucosa, generaly occuring 3 to 4 months after primary infection. Specific antiparasitic treatment is indicated to all patients infected by Schistosoma. There are 2 drugs available for treatment, praziquantel and oxamniquine. We revise the general aspects of the disease and describe the features of renal involvement in schistosomiasis.

  6. Surgical pathology of schistosomiasis.

    PubMed Central

    Mohammed, Aminu Z.; Edino, Steven T.; Samaila, Adamu A.

    2007-01-01

    Schistosomiasis remains an important health problem in many tropical countries and is being seen with increasing frequency in immigrant populations and tourists in developed countries. The pattern of organ involvement and clinical presentation of schistosomiasis in 80 patients (male: female, 9:1) during a five-year period (2001-2005) was examined from archival histopathology records. The urinary bladder was the most common organ affected [50 (62.5%)]. Gastrointestinal, male and female genital schistosomiasis were detected in 12 (15%), eight (10%) and five (6.1%) cases, respectively. Hematuria was the most common presenting symptom [34 (42.5%)], and bladder cancer was the only malignancy found to be associated with the infection. A high clinical index of suspicion usually allows for a preoperative diagnosis where indicated and avoidance of radical surgery. While research for the development of an effective vaccine continues, a plea is made for the expansion of multinational control programs in sub-Saharan Africa. PMID:17534016

  7. Schistosomiasis: Traverers in Africa.

    PubMed

    Strohmayer, Jeremy; Matthews, Ian; Locke, Robert

    2016-01-01

    Schistosomiasis is a parasitic infection acquired through freshwater exposure in the tropics. It is an infection that can have devastating implications to military personnel if it is not recognized and treated, especially later in life. While there is an abundance of information available about schistosomiasis in endemic populations, the information on nonendemic populations, such as deployers, is insufficient. Definitive studies for this population are lacking, but there are actions that can and should be taken to prevent infection and to treat patients. This literary review presents a case study, reviews basic science, and explores the information available about schistosomiasis in nonendemic populations. Specifically, the authors provide recommendations for the prevention, diagnosis, and postexposure management in military personnel.

  8. A Schistosomiasis Research Agenda

    PubMed Central

    Colley, Daniel G.; Secor, W. Evan

    2007-01-01

    There is a long and rich history of research and control in the field of schistosomiasis that has resulted in major scientific and public health accomplishments. Examples of such findings and accomplishments include immunologic regulation in chronic infections [1], the association of helminth infections with Th1-regulating Th2-type immune responses [2], the critical role of interleukin-13 in fibrogenesis [3], and the development and validation of the “dose pole” for determining praziquantel dosages in the field [4],[5]. Perhaps in part because of this broad and successful history, those who work on schistosomiasis come from a wide variety of backgrounds and interests. While such variety is enriching to the field, it sometimes results in diverse opinions about which of the many research opportunities should be pursued. Such diversity, we believe, has at times led to a divisiveness that has harmed overall progress in the field. Partly in response to such events, we have worked with as many of those interested in schistosomiasis as we could identify to develop what we feel is a comprehensive and cohesive agenda for schistosomiasis research (Image 1). PMID:18060081

  9. Myocyte apoptosis during acute myocardial infarction in the mouse localizes to hypoxic regions but occurs independently of p53.

    PubMed Central

    Bialik, S; Geenen, D L; Sasson, I E; Cheng, R; Horner, J W; Evans, S M; Lord, E M; Koch, C J; Kitsis, R N

    1997-01-01

    Significant numbers of myocytes die by apoptosis during myocardial infarction. The molecular mechanism of this process, however, remains largely unexplored. To facilitate a molecular genetic analysis, we have developed a model of ischemia-induced cardiac myocyte apoptosis in the mouse. Surgical occlusion of the left coronary artery results in apoptosis, as indicated by the presence of nucleosome ladders and in situ DNA strand breaks. Apoptosis occurs mainly in cardiac myocytes, and is shown for the first time to be limited to hypoxic regions during acute infarction. Since hypoxia-induced apoptosis in other cell types is dependent on p53, and p53 is induced by hypoxia in cardiac myocytes, we investigated the necessity of p53 for myocyte apoptosis during myocardial infarction. Myocyte apoptosis occurs as readily, however, in the hearts of mice nullizygous for p53 as in wild-type littermates. These data demonstrate the existence of a p53-independent pathway that mediates myocyte apoptosis during myocardial infarction. PMID:9294101

  10. [Schistosomiasis and acute appendicitis].

    PubMed

    Figueiredo, Jacinta; Santos, Ângela; Clemente, Horácio; Lourenço, Augusto; Costa, Sandra; Grácio, Maria Amélia; Belo, Silvana

    2014-01-01

    Acute appendicitis associated to Schistosoma haematobium and S. mansoni infection has been found in patients submitted to urgent appendectomy at the Hospital Américo Boavida in Luanda. Due to the high prevalence and morbidity caused by schistosomiasis (or bilharziasis) in the country, we suspect that the involvement of Schistosoma infection on appendicular pathology could be very frequent, in particular for those individuals more exposed to the parasite transmission. We report two clinical cases of acute appendicitis whose surgical specimens of the appendix revealed S. haematobium and S. mansoni eggs in histological samples. The reported patients live in endemic areas and have been exposed to schistosome during childhood, which may explain the infection's chronicity. Information of these clinical cases could be relevant, particularly for surgery specialists and clinical pathologists, due to the possibility of finding more patients with concurrent appendicitis and schistosomiasis.

  11. [Endocervical schistosomiasis: case report].

    PubMed

    Delmondes, Leda Maria; Cruz, Mário Augusto Ferreira; Guimarães, Matheus Kummer Hora; Santana, Luan Garcez; Gonçalves, Valma Passos Chagas; Brito, Hugo Leite de Farias

    2014-06-01

    Schistosomiasis mansoni is found in different endemic areas of Brazil. It is a serious public health problem in Brazil and worldwide. Ectopic forms of the disease may affect the female reproductive system, representing a rare type of Schistosoma mansoni infection. A 26-year-old patient complained of vaginal discharge, dyspareunia and pain on palpation of the hypogastrium. Gynecological examination revealed an endocervical polyp. A biopsy was performed. Under microscopy, several granulomas surrounding degenerate and viable eggs of Schistosoma mansoni were seen. Treated with praziquantel, she was asymptomatic after four weeks of treatment. Vaginal discharge and dyspareunia may be secondary causes of cervicitis caused by Schistosoma mansoni. The search for eggs in routine vaginal smear or histological examination should be part of the gynecologic evaluation of patients from endemic areas, with the purpose of tracking ectopic schistosomiasis of the female genital tract.

  12. Immunology of schistosomiasis*

    PubMed Central

    1974-01-01

    This Memorandum, after summarizing the life cycle of the different species of human schistosome, reviews the present knowledge of the immunology of schistosomiasis. Each stage of the parasite contains antigen that may stimulate an immune response. However, at the moment there are no accepted serological in vitro tests that correlate with protection; this develops only after the host has experienced a living infection, which suggests that the stimulation of immunity is due to some metabolic process involving the release of protective antigen. The adult worm, however, seems to be able to escape the immune mechanism of the host. Specific antigens are also released by the eggs, and the immune response against these antigens seems to cause granuloma formation around the egg itself. The granuloma is the main lesion found in schistosomiasis. Evidence for protective immunity in experimental animals and man is reviewed, together with the possible mechanism by which the adult worm escapes the immune response of the host. A review of methods used for the diagnosis of schistosomiasis and a list of recommendations for further research are also included. PMID:4219757

  13. Hippocampal negative event-related potential recorded in humans during a simple sensorimotor task occurs independently of motor execution.

    PubMed

    Roman, Robert; Brázdil, Milan; Chládek, Jan; Rektor, Ivan; Jurák, Pavel; Světlák, Miroslav; Damborská, Alena; Shaw, Daniel J; Kukleta, Miloslav

    2013-12-01

    A hippocampal-prominent event-related potential (ERP) with a peak latency at around 450 ms is consistently observed as a correlate of hippocampal activity during various cognitive tasks. Some intracranial EEG studies demonstrated that the amplitude of this hippocampal potential was greater in response to stimuli requiring an overt motor response, in comparison with stimuli for which no motor response is required. These findings could indicate that hippocampal-evoked activity is related to movement execution as well as stimulus evaluation and associated memory processes. The aim of the present study was to investigate the temporal relationship between the hippocampal negative potential latency and motor responses. We analyzed ERPs recorded with 22 depth electrodes implanted into the hippocampi of 11 epileptic patients. Subjects were instructed to press a button after the presentation of a tone. All investigated hippocampi generated a prominent negative ERP peaking at ~420 ms. In 16 from 22 cases, we found that the ERP latency did not correlate with the reaction time; in different subjects, this potential could either precede or follow the motor response. Our results indicate that the hippocampal negative ERP occurs independently of motor execution. We suggest that hippocampal-evoked activity, recorded in a simple sensorimotor task, is related to the evaluation of stimulus meaning within the context of situation.

  14. Voltage-Dependent Inactivation of MscS Occurs Independently of the Positively Charged Residues in the Transmembrane Domain

    PubMed Central

    Sokabe, Masahiro; Yoshimura, Kenjiro

    2016-01-01

    MscS (mechanosensitive channel of small conductance) is ubiquitously found among bacteria and plays a major role in avoiding cell lysis upon rapid osmotic downshock. The gating of MscS is modulated by voltage, but little is known about how MscS senses membrane potential. Three arginine residues (Arg-46, Arg-54, and Arg-74) in the transmembrane (TM) domain are possible to respond to voltage judging from the MscS structure. To examine whether these residues are involved in the voltage dependence of MscS, we neutralized the charge of each residue by substituting with asparagine (R46N, R54N, and R74N). Mechanical threshold for the opening of the expressed wild-type MscS and asparagine mutants did not change with voltage in the range from −40 to +100 mV. By contrast, inactivation process of wild-type MscS was strongly affected by voltage. The wild-type MscS inactivated at +60 to +80 mV but not at −60 to +40 mV. The voltage dependence of the inactivation rate of all mutants tested, that is, R46N, R54N, R74N, and R46N/R74N MscS, was almost indistinguishable from that of the wild-type MscS. These findings indicate that the voltage dependence of the inactivation occurs independently of the positive charges of R46, R54, and R74. PMID:28101504

  15. Immunology of human schistosomiasis

    PubMed Central

    Colley, D G; Secor, W E

    2014-01-01

    There is a wealth of immunologic studies that have been carried out in experimental and human schistosomiasis that can be classified into three main areas: immunopathogenesis, resistance to reinfection and diagnostics. It is clear that the bulk of, if not all, morbidity due to human schistosomiasis results from immune-response-based inflammation against eggs lodged in the body, either as regulated chronic inflammation or resulting in fibrotic lesions. However, the exact nature of these responses, the antigens to which they are mounted and the mechanisms of the critical regulatory responses are still being sorted out. It is also becoming apparent that protective immunity against schistosomula as they develop into adult worms develops slowly and is hastened by the dying of adult worms, either naturally or when they are killed by praziquantel. However, as with anti-egg responses, the responsible immune mechanisms and inducing antigens are not clearly established, nor are any potential regulatory responses known. Finally, a wide variety of immune markers, both cellular and humoral, can be used to demonstrate exposure to schistosomes, and immunologic measurement of schistosome antigens can be used to detect, and thus diagnose, active infections. All three areas contribute to the public health response to human schistosome infections. PMID:25142505

  16. Molluscicides in schistosomiasis control

    PubMed Central

    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 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. PMID:6975179

  17. Schistosomiasis control: praziquantel forever?

    PubMed

    Cioli, Donato; Pica-Mattoccia, Livia; Basso, Annalisa; Guidi, Alessandra

    2014-06-01

    Since no vaccine exists against schistosomiasis and the molluscs acting as intermediate hosts are not easy to attack, chemotherapy is the main approach for schistosomiasis control. Praziquantel is currently the only available antischistosomal drug and it is distributed mainly through mass administration programs to millions of people every year. A number of positive features make praziquantel an excellent drug, especially with regard to safety, efficacy, cost and ease of distribution. A major flaw is its lack of efficacy against the immature stages of the parasite. In view of its massive and repeated use on large numbers of individuals, the development of drug resistance is a much feared possibility. The mechanism of action of praziquantel is still unclear, a fact that does not favor the development of derivatives or alternatives. A large number of compounds have been tested as potential antischistosomal agents. Some of them are promising, but none so far represents a suitable substitute or adjunct to praziquantel. The research of new antischistosomal compounds is an imperative and urgent matter.

  18. [Schistosomiasis epidemiology (author's transl)].

    PubMed

    Picq, J J; Roux, J

    1980-01-01

    Schistosomiasis are, with three hundred million of infested people, the second world endemy, after malaria. For each of the four species, the distribution areas, the life cycle and the main epidemiological features are recalled in the first chapter. In the five following chapters, the authors consider the human or animal reservoirs of virus, the importance of these diseases towards public health, the gasteropod molluscs acting as intermediate hosts, and the problems of immunity in man. The concepts of "schistosomian infection" and "schistosomian disease" are exposed as well as the differences affecting the various strains of schistosomes and snails intermediate hosts. The authors emphasize the value of quantitative parasitological techniques and sero-immunological methods for epidemiological surveys. They underline the difficulties met in the evaluation of the effect of these diseases upon public health. The main causes inducing the duration of the endemy and those responsible for its extension are studied. The value of mathematic patterns is briefly discussed. Quantitative data compiled through epidemiological surveys should improve the use of the various means presently available for controling schistosomiasis.

  19. Development of a schistosomiasis vaccine.

    PubMed

    Molehin, Adebayo J; Rojo, Juan U; Siddiqui, Sabrina Z; Gray, Sean A; Carter, Darrick; Siddiqui, Afzal A

    2016-05-01

    Schistosomiasis is a neglected tropical disease (NTD) of public health importance. Despite decades of implementation of mass praziquantel therapy programs and other control measures, schistosomiasis has not been contained and continues to spread to new geographic areas. A schistosomiasis vaccine could play an important role as part of a multifaceted control approach. With regards to vaccine development, many biological bottlenecks still exist: the lack of reliable surrogates of protection in humans; immune interactions in co-infections with other diseases in endemic areas; the potential risk of IgE responses to antigens in endemic populations; and paucity of appropriate vaccine efficacy studies in nonhuman primate models. Research is also needed on the role of modern adjuvants targeting specific parts of the innate immune system to tailor a potent and protective immune response for lead schistosome vaccine candidates with the long-term aim to achieve curative worm reduction. This review summarizes the current status of schistosomiasis vaccine development.

  20. New diagnostic tools in schistosomiasis.

    PubMed

    Utzinger, J; Becker, S L; van Lieshout, L; van Dam, G J; Knopp, S

    2015-06-01

    Schistosomiasis is a water-based parasitic disease that affects over 250 million people. Control efforts have long been in vain, which is one reason why schistosomiasis is considered a neglected tropical disease. However, since the new millennium, interventions against schistosomiasis are escalating. The initial impetus stems from a 2001 World Health Assembly resolution, urging member states to scale-up deworming of school-aged children with the anthelminthic drug praziquantel. Because praziquantel is safe, efficacious and inexpensive when delivered through the school platform, diagnosis before drug intervention was deemed unnecessary and not cost-effective. Hence, there was little interest in research and development of novel diagnostic tools. With the recent publication of the World Health Organization (WHO) Roadmap to overcome the impact of neglected tropical diseases in 2020, we have entered a new era. Elimination of schistosomiasis has become the buzzword and this has important ramifications for diagnostic tools. Indeed, measuring progress towards the WHO Roadmap and whether local elimination has been achieved requires highly accurate diagnostic assays. Here, we introduce target product profiles for diagnostic tools that are required for different stages of a schistosomiasis control programme. We provide an update of the latest developments in schistosomiasis diagnosis, including microscopic techniques, rapid diagnostic tests for antigen detection, polymerase chain reaction (PCR) assays and proxy markers for morbidity assessments. Particular emphasis is placed on challenges and solutions for new technologies to enter clinical practice.

  1. Acute schistosomiasis among Americans rafting the Omo River, Ethiopia.

    PubMed

    Istre, G R; Fontaine, R E; Tarr, J; Hopkins, R S

    1984-01-27

    An outbreak of acute schistosomiasis occurred among a group of adventurers who took part in a rafting expedition on the Omo River in Ethiopia in November 1981. Six (55%) of the 11 members of the expedition experienced Schistosoma mansoni infection confirmed by stool examination. Five of these six had symptoms compatible with acute schistosomiasis. Eosinophilia was the most frequent sign of infection (five of six), and fever, the most common symptom (four of six). Despite medical evaluations, illnesses had remained undiagnosed until January 1982. This outbreak should alert physicians to the risk of schistosomiasis among travelers to this part of Africa and the difficulty of correct diagnosis early in the course of the disease.

  2. Towards control of schistosomiasis in sub-Saharan Africa.

    PubMed

    Southgate, V R; Rollinson, D; Tchuem Tchuenté, L A; Hagan, P

    2005-09-01

    Approximately 80% of the 200 million people infected with schistosomiasis inhabit sub-Saharan Africa, and the annual mortality is estimated to be 280,000. Praziquantel is the drug of choice in the treatment of schistosomiasis and pregnant women may now be treated. It was agreed at the World Health Assembly in 2001 that at least 75% of school-aged children in high burden areas should be treated for schistosomiasis and soil-transmitted helminth infections by 2010 to reduce morbidity. A grant from the Bill and Melinda Gates Foundation to the Schistosomiasis Control Initiative, Imperial College of Science, Technology and Medicine, London has enabled control programmes to be initiated in Uganda, Tanzania, Zambia, Burkina Faso, Niger and Mali. Additional programmes have recently commenced in Zanzibar with a grant from the Health Foundation to The Natural History Museum, London and in Cameroon. Combination treatment for schistosomiasis, gastrointestinal helminths and filariasis reduces costs of control programmes. The EC Concerted Action Group on 'Praziquantel: its central role in the chemotherapy of schistosome infection' met in Yaoundé Cameroon in 2004 to discuss recent developments in laboratory and field studies. The use of standard operating procedures will enable data on drug action on schistosomes produced in different laboratories to be compared. With the ever increasing use of praziquantel there is a possibility of the development of resistance by schistosomes to the drug, hence the necessity to explore the activities of other compounds. Artemether, unlike praziquantel, is effective against immature schistosomes. The effectiveness of mirazid, an extract of myrrh, is controversial as data from different laboratories are equivocal. It is suggested that an independent body such as the World Health Organization should determine whether mirazid should be used in the treatment of schistosomiasis.

  3. Close, stable homolog juxtaposition during meiosis in budding yeast is dependent on meiotic recombination, occurs independently of synapsis, and is distinct from DSB-independent pairing contacts

    PubMed Central

    Peoples, Tamara L.; Dean, Eric; Gonzalez, Oscar; Lambourne, Lindsey; Burgess, Sean M.

    2002-01-01

    A site-specific recombination system that probes the relative probabilities that pairs of chromosomal loci collide with one another in living cells of budding yeast was used to explore the relative contributions of pairing, recombination, synaptonemal complex formation, and telomere clustering to the close juxtaposition of homologous chromosome pairs during meiosis. The level of Cre-mediated recombination between a pair of loxP sites located at an allelic position on homologous chromosomes was 13-fold greater than that between a pair of loxP sites located at ectopic positions on nonhomologous chromosomes. Mutations affecting meiotic recombination initiation and the processing of DNA double-strand breaks (DSBs) into single-end invasions (SEIs) reduced the levels of allelic Cre-mediated recombination levels by three- to sixfold. The severity of Cre/loxP phenotypes is presented in contrast to relatively weak DSB-independent pairing defects as assayed using fluorescence in situ hybridization for these mutants. Mutations affecting synaptonemal complex (SC) formation or crossover control gave wild-type levels of allelic Cre-mediated recombination. A delay in attaining maximum levels of allelic Cre-mediated recombination was observed for a mutant defective in telomere clustering. None of the mutants affected ectopic levels of recombination. These data suggest that stable, close homolog juxtaposition in yeast is distinct from pre-DSB pairing interactions, requires both DSB and SEI formation, but does not depend on crossovers or SC. PMID:12101126

  4. Still hope for schistosomiasis vaccine

    PubMed Central

    Ricciardi, Alessandra; Ndao, Momar

    2015-01-01

    Schistosomiasis is a parasitic disease caused by helminths belonging to the Schistosoma genus. Approximately 700 million people are at risk of infection and 200 million people are currently infected. Schistosomiasis is the most important helminth infection, and treatment relies solely on the drug praziquantel. Worries of praziquantel resistance as well as high disease burden are only some of the justifications which support the development of a vaccine against schistosomiasis. To date, only 2 schistosome vaccines have made it into clinical trials: Sh28GST (Bilhvax) and Sm14. However, there are several vaccine candidates, such as TSP-2, sm-p8, and Sm-Cathepsin B, which are generating promising results in pre-clinical studies. Schistosomiasis vaccine development has been an uphill battle, and there are still several hurdles to overcome in the future. Fortunately, the research groups involved in the research for vaccine development have not abandoned their work. Furthermore, in the last few years, schistosomiasis has garnered some additional attention on a global scale due to its significant impact on public health. PMID:26176659

  5. Still hope for schistosomiasis vaccine.

    PubMed

    Ricciardi, Alessandra; Ndao, Momar

    2015-01-01

    Schistosomiasis is a parasitic disease caused by helminths belonging to the Schistosoma genus. Approximately 700 million people are at risk of infection and 200 million people are currently infected. Schistosomiasis is the most important helminth infection, and treatment relies solely on the drug praziquantel. Worries of praziquantel resistance as well as high disease burden are only some of the justifications which support the development of a vaccine against schistosomiasis. To date, only 2 schistosome vaccines have made it into clinical trials: Sh28GST (Bilhvax) and Sm14. However, there are several vaccine candidates, such as TSP-2, sm-p8, and Sm-Cathepsin B, which are generating promising results in pre-clinical studies. Schistosomiasis vaccine development has been an uphill battle, and there are still several hurdles to overcome in the future. Fortunately, the research groups involved in the research for vaccine development have not abandoned their work. Furthermore, in the last few years, schistosomiasis has garnered some additional attention on a global scale due to its significant impact on public health.

  6. PKC-Dependent GlyT1 Ubiquitination Occurs Independent of Phosphorylation: Inespecificity in Lysine Selection for Ubiquitination

    PubMed Central

    Barrera, Susana P.; Castrejon-Tellez, Vicente; Trinidad, Margarita; Robles-Escajeda, Elisa; Vargas-Medrano, Javier; Varela-Ramirez, Armando; Miranda, Manuel

    2015-01-01

    Neurotransmitter transporter ubiquitination is emerging as the main mechanism for endocytosis and sorting of cargo into lysosomes. In this study, we demonstrate PKC-dependent ubiquitination of three different isoforms of the glycine transporter 1 (GlyT1). Incubation of cells expressing transporter with the PKC activator phorbol ester induced a dramatic, time-dependent increase in GlyT1 ubiquitination, followed by accumulation of GlyT1 in EEA1 positive early endosomes. This occurred via a mechanism that was abolished by inhibition of PKC. GlyT1 endocytosis was confirmed in both retinal sections and primary cultures of mouse amacrine neurons. Replacement of only all lysines in the N-and C-termini to arginines prevented ubiquitination and endocytosis, displaying redundancy in the mechanism of ubiquitination. Interestingly, a 40–50% reduction in glycine uptake was detected in phorbol-ester stimulated cells expressing the WT-GlyT1, whereas no significant change was for the mutant protein, demonstrating that endocytosis participates in the reduction of uptake. Consistent with previous findings for the dopamine transporter DAT, ubiquitination of GlyT1 tails functions as sorting signal to deliver transporter into the lysosome and removal of ubiquitination sites dramatically attenuated the rate of GlyT1 degradation. Finally, we showed for the first time that PKC-dependent GlyT1 phosphorylation was not affected by removal of ubiquitination sites, suggesting separate PKC-dependent signaling events for these posttranslational modifications. PMID:26418248

  7. The schistosomiasis problem in Egypt.

    PubMed

    Mobarak, A B

    1982-01-01

    This report provides an overview of past and current efforts to control schistosomiasis in Egypt, describes recent trends, and analyzes factors responsible for changes in transmission. For the purpose of long-term planning and developing control strategies, the country has been divided into eight geographic zones: Suez Canal Zone, Sainai, Nile Delta, Guiza, Fayoum, Middle Egypt, Upper Egypt, and the High Dam Lake Zone. Overall control priorities are examined and the strategy for each zone is described. The most recent information on changes in epidemiologic patterns of schistosomiasis in Egypt is mentioned, as well as the introduction of newer therapeutic agents. Lastly, the role of outside funding agencies in supporting schistosomiasis control is examined.

  8. GATA Factor Regulation in Excess Nitrogen Occurs Independently of Gtr-Ego Complex-Dependent TorC1 Activation

    PubMed Central

    Tate, Jennifer J.; Georis, Isabelle; Rai, Rajendra; Vierendeels, Fabienne; Dubois, Evelyne; Cooper, Terrance G.

    2015-01-01

    The TorC1 protein kinase complex is a central component in a eukaryotic cell’s response to varying nitrogen availability, with kinase activity being stimulated in nitrogen excess by increased intracellular leucine. This leucine-dependent TorC1 activation requires functional Gtr1/2 and Ego1/3 complexes. Rapamycin inhibition of TorC1 elicits nuclear localization of Gln3, a GATA-family transcription activator responsible for the expression of genes encoding proteins required to transport and degrade poor nitrogen sources, e.g., proline. In nitrogen-replete conditions, Gln3 is cytoplasmic and Gln3-mediated transcription minimal, whereas in nitrogen limiting or starvation conditions, or after rapamycin treatment, Gln3 is nuclear and transcription greatly increased. Increasing evidence supports the idea that TorC1 activation may not be as central to nitrogen-responsive intracellular Gln3 localization as envisioned previously. To test this idea directly, we determined whether Gtr1/2- and Ego1/3-dependent TorC1 activation also was required for cytoplasmic Gln3 sequestration and repressed GATA factor-mediated transcription by abolishing the Gtr-Ego complex proteins. We show that Gln3 is sequestered in the cytoplasm of gtr1Δ, gtr2Δ, ego1Δ, and ego3Δ strains either long term in logarithmically glutamine-grown cells or short term after refeeding glutamine to nitrogen-limited or -starved cells; GATA factor−dependent transcription also was minimal. However, in all but a gtr1Δ, nuclear Gln3 localization in response to nitrogen limitation or starvation was adversely affected. Our data demonstrate: (i) Gtr-Ego-dependent TorC1 activation is not required for cytoplasmic Gln3 sequestration in nitrogen-rich conditions; (ii) a novel Gtr-Ego-TorC1 activation-independent mechanism sequesters Gln3 in the cytoplasm; (iii) Gtr and Ego complex proteins participate in nuclear Gln3-Myc13 localization, heretofore unrecognized functions for these proteins; and (iv) the importance of

  9. [Eradication of schistosomiasis: a new target and a new task for the National Schistosomiasis Control Porgramme in the People's Republic of China].

    PubMed

    Lei, Zheng-long; Zhou, Xiao-Nong

    2015-02-01

    The achievements for the national schistosomiasis control programme in the People's Republic of China over the last 6 decades were reviewed, with an emphasis on the status and challenges to accomplish the tasks of "Workplan for the Mid- and Long-term of National Schistosomiasis Control Programme from 2004 to 2015". Four features of current national schistosomiasis control programme were identified in the new stage. First, the high prevalence areas have been shrunk, but few regions are still at the risks of schitosomiasis rebounding. Second, large areas with low prevalence of schistosomiasis will remain for a long time, so that the disease surveillance will be a long-term task. Third, more notable places will be in the high risk areas where more activities of human and livestock occurred, so that it is essential to implement the integrated control measures in those high risk areas. Fourth, the technologies using in the schistosomiasis eradication programme are delayed as expected, and more needs to accelerate the R&D programmes. It was recommended that sustained implementation of integrated control strategy with more emphasis on control of infectious sources has to be strengthened through enhanced regulation performance in addition to the aforementioned notifications, in order to eradicate schistosomiasis in a response to the newly formulated target of "making the 'God of Plague' to be sweep away from the history, and retuning the clear land/water and happy/healthy life to the people".

  10. [Schistosomiasis in an ecotourism area in Minas Gerais State, Brazil].

    PubMed

    Massara, Cristiano Lara; Amaral, Graciela Larissa; Caldeira, Roberta Lima; Drummond, Sandra Costa; Enk, Martin Johannes; Carvalho, Omar dos Santos

    2008-07-01

    This paper discusses schistosomiasis transmission in São José da Serra, a village with a population of 500 in the county of Jaboticatubas, Minas Gerais State, Brazil. The area receives thousands of visitors a year for ecotourism. The study was motivated by a case of acute schistosomiasis involving a couple that spent the 2007 Carnival (Mardi Gras) holiday in the area. Stool tests from 268 local residents (53.6% of the population) showed that 35 (13%) were positive for the infection. A comparison with a previous survey (2005) in the same location showed an increase in the schistosomiasis-positive rate from 9.6% to 12.5%, among the 56 individuals who participated in both surveys. A malacological survey of 65 Biomphalaria glabrata snails showed one specimen (1.5%) eliminating cercariae. In a similar survey in 2005, no positive snail specimens were found. The study indicates that active schistosomiasis transmission is occurring in the area, and that integrated educational programs are needed for both the local community and tourists.

  11. Alternative approaches in schistosomiasis control.

    PubMed

    Barbosa, F S; Coimbra Júnior, C E

    1992-01-01

    Measures for the control of schistosomiasis were implemented in Egypt beginning 1922. This shows that developing endemic countries are facing this problem for near 70 years. However, results in the control of this infection have not been satisfactorily obtained in spite of the technologies and strategies recently developed. The idea that social and economic components are relevant in the control of schistosomiasis is not new although its extension and profundity have not usually been well understood. More recently, most of the workers have recognized that the focal distribution of the prevalence rates of schistosomiasis should not be neglected in the control of the infection. At present, field work projects on the control of schistosomiasis are being developed in rural areas of two Brazilian studies (Espírito Santo and Pernambuco). The adopted strategy aims to interfere in the complex relationships between man and his bio-social-cultural environment, without forgetting that the unequal distribution of the space is a consequence of the political and economic organization of the Society.

  12. Schistosomiasis collection at NHM (SCAN)

    PubMed Central

    2012-01-01

    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. PMID:22943137

  13. Noradrenaline-induced contraction of mice aorta is enhanced in schistosomiasis.

    PubMed

    Silva, C L M; Gontijo, L S; Noël, F

    2007-02-01

    Schistosomiasis, an intravascular parasitic disease caused by Schistosoma mansoni, is related to alterations of murine vascular reactivity in the mesenteric bed, characterized by an impairment of the l-arginine/NO pathway and an increased potency of 5-hydroxytryptamine. The current study was performed to test the hypothesis that a similar alteration of reactivity also occurs in the aorta and to identify the mechanism behind such an increase. We found that aorta from mice infected with male S. mansoni exhibited an enhanced contraction in response to noradrenaline and 100 mM KCl. The inhibition of nitric oxide synthase increased aortic maximal contraction in response to noradrenaline in both groups, but the effect was less pronounced in infected mice than in control mice. Endothelium-dependent relaxation induced by acetylcholine was also smaller in infected mice compared to control mice, while endothelial-independent relaxation induced by sodium nitroprusside and forskolin was similar in both groups. The inhibition of voltage-dependent L-type Ca(2+) channels reduced the maximal contraction in response to noradrenaline more effectively in infected than in control mice. Conversely the inhibition of K(ATP) channels had a smaller effect in the infected group. As a conclusion, our data indicate that schistosomiasis also alters murine vascular reactivity outside the mesenteric bed, due to a partial impairment of NO signaling, a reduced contribution of K(ATP) channels and an increased Ca(2+) influx through L-type Ca(2+) channels.

  14. Control of schistosomiasis in Brazil: perspectives and proposals.

    PubMed

    Coura, J R

    1995-01-01

    Attempts to control schistosomiasis have hitherto involved the use of one or more of the following methods, either in isolation or in combination: (1) control of the intermediate host using molluscicides or biological methods; (2) basic sanitation and clean water supply; (3) health education; (4) individual or mass treatment; (5) protection of individuals in such a way as to prevent cercariae from penetrating the skin; (6) vaccine-based strategies against schistosomiasis. None of these methods is capable, on its own, of bringing about effective control of schistosomiasis, except in populations of a very limited size or under very special conditions. Molluscicides, besides expensive and toxic, have only a temporary effect. As for biological control, there is no effective method yet. Basic sanitation and clean water supply combined with health education potentially constitute the most effective approach, but only in the mid-to-long term. Mass treatment reduces morbidity, but does not control transmission. Protection of individuals has proved to be impracticable on a large scale. Vaccine-based strategies against schistosomiasis are still in the experimental stage. Experiments carried out in Brazil in the last 20 years have shown that mass treatment with single doses of oxamniquine or praziquantel can rapidly reduce levels of Shistosoma mansoni infection and morbidity in endemic areas. They have also shown that subsequent transmission and reinfection frequently occur in defined foci or "clusters", due to human contact with water, and in inverse proportion to the number and frequency of treatments carried out. On the basis of these experiments, the author suggests a multidisciplinary strategy for schistosomiasis control.

  15. Genitourinary schistosomiasis: life cycle and radiologic-pathologic findings.

    PubMed

    Shebel, Haytham M; Elsayes, Khaled M; Abou El Atta, Heba M; Elguindy, Yehia M; El-Diasty, Tarek A

    2012-01-01

    Genitourinary schistosomiasis is produced by Schistosoma haematobium, a species of fluke that is endemic to Africa and the Middle East, and causes substantial morbidity and mortality in those regions. It also may be seen elsewhere, as a result of travel or immigration. S haematobium, one of the five fluke species that account for most human cases of schistosomiasis, is the only species that infects the genitourinary system, where it may lead to a wide spectrum of clinical symptoms and signs. In the early stages, it primarily involves the bladder and ureters; later, the kidneys and genital organs are involved. It rarely infects the colon or lungs. A definitive diagnosis of genitourinary schistosomiasis is based on findings of parasite ova at microscopic urinalysis. Clinical manifestations and radiologic imaging features also may be suggestive of the disease, even at an early stage: Hematuria, dysuria, and hemospermia, early clinical signs of an established S haematobium infection, appear within 3 months after infection. At imaging, fine ureteral calcifications that appear as a line or parallel lines on abdominopelvic radiographs and as a circular pattern on axial images from computed tomography (CT) are considered pathognomonic of early-stage schistosomiasis. Ureteritis, pyelitis, and cystitis cystica, conditions that are characterized by air bubble-like filling defects representing ova deposited in the ureter, kidney, and bladder, respectively, may be seen at intravenous urography, intravenous ureteropyelography, and CT urography. Coarse calcification, fibrosis, and strictures are signs of chronic or late-stage schistosomiasis. Such changes may be especially severe in the bladder, creating a predisposition to squamous cell carcinoma. Genital involvement, which occurs more often in men than in women, predominantly affects the prostate and seminal vesicles.

  16. [Travel related urinary schistosomiasis: case report].

    PubMed

    Özvatan, Tülay Şener; Koçak, Cengiz; Alver, Oktay; Mıstık, Reşit; Aslan, Emel

    2011-01-01

    Schistosomiasis is the second most frequent parasitic infection worldwide after malaria and is a major public health problem in various countries of the world. In our country due to the increasingf travel to endemic regions, the number of cases is also rising. We report herein a case of schistosomiasis who resided in Africa five years earlier and was referred to hospital with hematuria. Direct microscopic examination of the urine specimen revealed Schistosoma haematobium eggs. Epidemiology and clinical significance of schistosomiasis are also discussed.

  17. The situation of hepatosplenic schistosomiasis in Brazil today.

    PubMed

    Andrade, Z A

    1998-01-01

    Specific chemotherapy against schistosomiasis together with environmental changes occurring in endemic areas of Brazil are causing a revolution in the clinico-pathological presentation of the disease when comparing to date from 10 to 15 years ago. To update the subject, an inquiry was made among the most experienced Brazilian investigators in this field. They agree that a decrease of about 50 to 70% in prevalence, and an even higher decrease in incidence are taking place in Brazil today. The prevalence of schistosome-infection has decreased in some areas and increased in other, with spreading sometimes occurring to peri-urban regions, indicating that schistosomiasis control depends on the application of multiple measures. General clinical and pathological manifestations related to hepatosplenic disease, such as ascites, gastric hemorrhages, big-spleen syndrome, cor pulmonale, glomerulopathy, etc. are also less severe nowadays than they used to be in the past.

  18. Schistosomiasis in Travelers and Expatriates.

    PubMed

    Jelinek; Nothdurft; Löscher

    1996-09-01

    Background: Several outbreaks of schistosomiasis among travelers, expatriates, and military serviceman have been reported in recent years. Methods: The travel histories and anamnestic and clinical features of 62 patients with schistosomiasis, who presented to a German outpatient clinic specializing in infectious and tropical diseases, were investigated to identify risk factors that could lead to infection in travelers and expatriates. Results: All patients remembered incidents that led to a likely exposure to cercariae of Schistosoma sp. Fifty nine patients (95%) acquired infection in Africa, two (3%) in South America, and one each (2% each) in Iraq and the Mekong River, respectively. The highest proportion of infection (45%) was imported from West Africa. Patients returning from West Africa reported either contact with tributaries of the Niger (including freshwater pools in the Dogon country, Mali) or with waters of the Volta River, notably Lake Volta and/or its delta. Six patients (10%) acquired infection in little-visited areas such as Central Africa and the Congo Basin. East Africa (especially Lake Victoria) and Lake Malawi contributed 14 patients (22%) to our study group; a further nine patients (14%) became infected after contact with waters of the Zambezi River. Conclusions: The most sensitive method for detection of possible infection with schistosomiasis appeared to be a combination of thorough travel history and serologic testing by indirect hemagglutination (IHA), immunofluorescence antibody test (IFAT), and enzyme-linked immunosorbent assay (ELISA). Most infections were acquired by travelers on lengthy and adventurous journeys or by expatriates venturing outside their normal areas of activity. Most patients knew that they had traveled in an area endemic for schistosomiasis, but were uninformed about behavioral risks they had taken in specific settings.

  19. Schistosomiasis in non-endemic countries.

    PubMed

    Coltart, Cordelia; Whitty, Christopher J M

    2015-02-01

    Schistosomiasis is one of the major parasitic diseases of the tropics, causing acute and long-term clinical syndromes. Almost all schistosomiasis is now imported from sub-Saharan Africa. This article summarises the aetiology, clinical presentation, diagnosis and management of schistosomiaisis for clinicians in non-endemic countries.

  20. Schistosomiasis Japonicum Involving the Liver and Colon

    DTIC Science & Technology

    2007-02-01

    presentation, typical imaging findings, and treatment of Schistosomiasis. Schistosomiasis is a chronic infection caused by parasitic trematode worms that...ova are subsequently deposited within the liver, gastrointestinal tract, and genitourinary tract and a granulomatous and fibrotic reaction ensues...potentially result in permanent gastrointestinal and urinary system damage if not appropriately treated. History A 51-year-old female

  1. Impact of schistosomiasis on increase incidence of occult hepatitis B in chronic hepatitis C patients in Egypt.

    PubMed

    Omar, Hanan H; Taha, Samaa A; Hassan, Wafaa H; Omar, Hamdy H

    2017-02-09

    Co-infection of schistosomiasis, HBV and HCV is common in countries where schistosomiasis is endemic. Occult hepatitis B occurs in patients at high risk for HBV infection (e.g., patients on hemodialysis, patients receiving blood transfusions). Schistosomal infection is a risk factor of HBV infection that can increase the incidence of occult hepatitis B. We aimed to determine the prevalence of occult hepatitis B in chronic hepatitis C patients with and without schistosomiasis and to assess the effect of schistosomal infection on the increased risk of exposure to HBV infection and to occult hepatitis B. Two hundred chronic hepatitis C patients who were negative for HBsAg participated. All patients were tested for the following: Anti-schistosome antibodies, Anti-HBc, serum HBV DNA, CBC and liver function. The prevalence of occult hepatitis B in CHC patients with/without schistosomiasis were 12.8% and 8.5% (P=0.042), respectively. Next, 63.8% of CHC patients with schistosomiasis were exposed to HBV infection (Anti-HBc +ve) during their lifetime. In conclusion, the prevalence of occult hepatitis B is higher in CHC patients with schistosomiasis compared to those without schistosomiasis. Periodic laboratory investigations of Schistosoma mansoni, HBV and HCV are recommended for the early detection of the infection and, especially in endemic areas, to avoid infection complications.

  2. [Urinary schistosomiasis in ancient Egypt].

    PubMed

    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.

  3. Changing policy and practice in the control of pediatric schistosomiasis.

    PubMed

    Mutapi, Francisca

    2015-03-01

    Schistosomiasis is a chronic disease that affects ∼200 million people. The extended health impact of the disease has been estimated to exceed that of malaria or tuberculosis and to be nearer to that of HIV/AIDS. Within endemic areas, children carry the heaviest burden of infection. Infection/disease is controlled by the treatment of infected subjects with the anthelminthic drug praziquantel. Global initiatives from Partners of Parasite Control, including the World Health Organization (WHO), advocate regular school-based deworming strategies to reduce the development of severe morbidity, promote school-child health and development, and improve the cognitive potential of children. Until recently, preschool-aged children were excluded from schistosome treatment, creating a health inequity in affected populations. In 2010, the WHO updated their recommendations for the treatment of schistosomiasis in preschool-aged children (ie, children aged ≤5 years). This change was the culmination of several decades of research on schistosome epidemiology, immunology, and pathology in this age group. The recent development of a pediatric formulation of praziquantel (soon to enter clinical trials) should advance control efforts in preschool-aged children, with the goal of including these children in preventative chemotherapy (as currently occurs for soil-transmitted helminths). This review discusses the research work supporting the WHO revision of recommendations for treating preschool-aged children, as well as current barriers and knowledge gaps in pediatric schistosomiasis control.

  4. Dracunculiasis, onchocerciasis, schistosomiasis, and trachoma.

    PubMed

    Hopkins, Donald R; Richards, Frank O; Ruiz-Tiben, Ernesto; Emerson, Paul; Withers, P Craig

    2008-01-01

    The four diseases discussed in this chapter (dracunculiasis, onchocerciasis, schistosomiasis, and trachoma) are among the officially designated "Neglected Tropical Diseases," and each is also both the result of and a contributor to the poverty of many rural populations. To various degrees, they all have adverse effects on health, agricultural productivity, and education. The Carter Center decided to work on these health problems because of their adverse effect on the lives of poor people and the opportunity to help implement effective interventions. As a result of the global campaign spearheaded by the Carter Center since 1986, the extent of dracunculiasis has been reduced from 20 to five endemic countries and the number of cases reduced by more than 99%. We have helped administer nearly 20% of the 530 million Mectizan (ivermectin) doses for onchocerciasis, which is now being controlled throughout most of Africa, and is progressing toward elimination in the Americas. Since 1999, two Nigerian states have been using village-based health workers originally recruited to work on onchocerciasis to also deliver mass treatment and health education for schistosomiasis and lymphatic filariasis. They now also distribute vitamin A supplements and bed nets to prevent malaria and lymphatic filariasis. Ethiopia aims to eliminate blinding trachoma in the Amhara Region of that highest-endemicity country by 2012, already constructing more than 300,000 latrines and other complementary interventions. Because of the synergy between these diseases and poverty, controlling or eliminating the disease also reduces poverty and increases self-reliance.

  5. T cell-independent IgA class switch recombination is restricted to the GALT and occurs prior to manifest germinal center formation.

    PubMed

    Bergqvist, Peter; Stensson, Anneli; Lycke, Nils Y; Bemark, Mats

    2010-04-01

    Recently, we reported that CD40(-/-) mice, exhibiting exclusively T cell-independent IgA class switch recombination (CSR), demonstrated near normal levels of IgA plasma cells in the gut lamina propria (LP), despite the complete lack of germinal centers (GCs). In this study, we have extended our analysis focusing on how to reconcile these findings using flow cytometry and molecular markers for IgA CSR. In agreement with our previous results with small intestinal LP, the colon LP was found to host IgA CSR only when lymphoid follicles were present. Thus, no IgA CSR was observed in the nonorganized colon LP. By contrast, the Peyer's patch (PP) was the dominant IgA CSR site in both CD40(-/-) and wild type (WT) mice, and they both hosted similar levels of mRNA expression for B cell activating factor of the TNF family, a proliferation inducing ligand, and inducible NO synthase, potential switch-factors for IgA. Unexpectedly, we found that PP B cells undergoing IgA CSR were GL7-intermediate. These cells had not undergone somatic hypermutations (SHMs), whereas GL7-high cells in WT PP, which exhibited GCs, were heavily mutated. Moreover, IgA plasma cells in the LP of CD40(-/-) mice demonstrated few mutations in their Ig V regions, whereas WT LP B cells from different sites showed extensive SHMs, which were also clonally related. Therefore, IgA CSR can occur in PP at a stage preceding manifest GC (GL7-intermediate), whereas SHM require GC formations (GL7-high). These findings reconcile that IgA CSR can occur in PP in the absence of GC with the fact that CD40(-/-) mice host near normal levels of IgA plasma cells in the LP.

  6. Hypoxia-Mediated Down-Regulation of Bid and Bax in Tumors Occurs via Hypoxia-Inducible Factor 1-Dependent and -Independent Mechanisms and Contributes to Drug Resistance

    PubMed Central

    Erler, Janine T.; Cawthorne, Christopher J.; Williams, Kaye J.; Koritzinsky, Marianne; Wouters, Bradley G.; Wilson, Clare; Miller, Crispin; Demonacos, Costas; Stratford, Ian J.; Dive, Caroline

    2004-01-01

    Solid tumors with disorganized, insufficient blood supply contain hypoxic cells that are resistant to radiotherapy and chemotherapy. Drug resistance, an obstacle to curative treatment of solid tumors, can occur via suppression of apoptosis, a process controlled by pro- and antiapoptotic members of the Bcl-2 protein family. Oxygen deprivation of human colon cancer cells in vitro provoked decreased mRNA and protein levels of proapoptotic Bid and Bad. Hypoxia-inducible factor 1 (HIF-1) was dispensable for the down-regulation of Bad but required for that of Bid, consistent with the binding of HIF-1α to a hypoxia-responsive element (positions −8484 to −8475) in the bid promoter. Oxygen deprivation resulted in proteosome-independent decreased expression of Bax in vitro, consistent with a reduction in global translation efficiency. The physiological relevance of Bid and Bax down-regulation was confirmed in tumors in vivo. Oxygen deprivation resulted in decreased drug-induced apoptosis and clonogenic resistance to agents with different mechanisms of action. The contribution of Bid and/or Bax down-regulation to drug responsiveness was demonstrated by the relative resistance of normoxic cells that had no or reduced expression of Bid and/or Bax and by the finding that forced expression of Bid in hypoxic cells resulted in increased sensitivity to the topoisomerase II inhibitor etoposide. PMID:15024076

  7. Adrenergic activation of melatonin secretion in ovine pineal explants in short-term superfusion culture occurs via protein synthesis independent and dependent phenomena.

    PubMed

    Lewczuk, Bogdan; Ziółkowska, Natalia; Prusik, Magdalena; Przybylska-Gornowicz, Barbara

    2014-01-01

    The ovine pineal is generally considered as an interesting model for the study on adrenergic regulation of melatonin secretion due to some functional similarities with this gland in the human. The present investigations, performed in the superfusion culture of pineal explants, demonstrated that the norepinephrine-induced elevation of melatonin secretion in ovine pinealocytes comprised of two subsequent periods: a rapid increase phase and a slow increase phase. The first one included the quick rise in release of N-acetylserotonin and melatonin, occurring parallel to elevation of NE concentration in the medium surrounding explants. This rapid increase phase was not affected by inhibition of translation. The second, slow increase phase began after NE level had reached the maximum concentration in the culture medium and lasted about two hours. It was completely abolished by the treatment with translation inhibitors. The obtained results showed for the first time that the regulation of N-acetylserotonin synthesis in pinealocytes of some species like the sheep involves the on/off mechanism, which is completely independent of protein synthesis and works very fast. They provided strong evidence pointing to the need of revision of the current opinion that arylalkylamines N-acetyltransferase activity in pinealocytes is controlled exclusively by changes in enzyme abundance.

  8. Schistosomiasis therapeutics: whats in the pipeline?

    PubMed

    Trainor-Moss, Santiago; Mutapi, Francisca

    2016-01-01

    Schistosomiasis is a debilitating neglected tropical disease caused by schistosome worms. Global efforts to control schistosomiasis rely predominantly on mass drug administration of the drug praziquantel to populations at risk of infection. We review the history of schistosome drug development and the current position of schistosome drug research. We conclude that with no additional candidates currently in the anti-schistosome drug clinical trial pipeline, a practical and necessary approach is to optimise the health benefits from praziquantel. We offer suggestions of where and how this can be achieved. We also highlight knowledge gaps in the utility of praziquantel particularly in the treatment of chronic schistosomiasis, which includes fibrosis, organomegaly and cervical lesions associated with female genital schistosomiasis.

  9. Interaction between Salmonella and Schistosomiasis: A Review

    PubMed Central

    Hsiao, Amber; Toy, Trevor; Marks, Florian

    2016-01-01

    The interaction between schistosomiasis and Salmonella is a particularly important issue in Africa, where dual infection by the parasite and the bacterium are likely common. In this review, the ways in which schistosomiasis affects human biology as it relates to Salmonella are described. Those who are infected by both organisms experience reduced immunological functioning, exhibit irreversible organ damage due to prolonged schistosomiasis infection, and become latent carriers of Salmonella enterica serotypes Typhi and Paratyphi and S. Typhimurium. The sequestration of the bacteria in the parasite leads to ineffective antibiotic treatment because the bacteria cannot be completely killed, and lingering infection may then lead to antimicrobial resistance. These manifestations are likely not just for those dually infected but also for those first infected with schistosomes and, later, Salmonella. More data are needed to better understand dual infection, particularly as it may impact treatment and prevention of schistosomiasis and Salmonella in sub-Saharan Africa. PMID:27907208

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

    PubMed

    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.

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

    PubMed Central

    2013-01-01

    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. PMID:23985040

  12. Schistosomiasis in the People's Republic of China: the Era of the Three Gorges Dam

    PubMed Central

    McManus, Donald P.; Gray, Darren J.; Li, Yuesheng; Feng, Zheng; Williams, Gail M.; Stewart, Donald; Rey-Ladino, Jose; Ross, Allen G.

    2010-01-01

    Summary: The potential impact of the Three Gorges Dam (TGD) on schistosomiasis transmission in China has invoked considerable global concern. The TGD will result in changes in the water level and silt deposition downstream, favoring the reproduction of Oncomelania snails. Combined with blockages of the Yangtze River's tributaries, these changes will increase the schistosomiasis transmission season within the marshlands along the middle and lower reaches of the Yangtze River. The changing schistosome transmission dynamics necessitate a comprehensive strategy to control schistosomiasis. This review discusses aspects of the epidemiology and transmission of Schistosoma japonicum in China and considers the pathology, clinical outcomes, diagnosis, treatment, immunobiology, and genetics of schistosomiasis japonica together with an overview of current progress in vaccine development, all of which will have an impact on future control efforts. The use of synchronous praziquantel (PZQ) chemotherapy for humans and domestic animals is only temporarily effective, as schistosome reinfection occurs rapidly. Drug delivery requires a substantial infrastructure to regularly cover all parts of an area of endemicity. This makes chemotherapy expensive and, as compliance is often low, a less than satisfactory control option. There is increasing disquiet about the possibility that PZQ-resistant schistosomes will develop. Consequently, as mathematical modeling predicts, vaccine strategies represent an essential component in the future control of schistosomiasis in China. With the inclusion of focal mollusciciding, improvements in sanitation, and health education into the control scenario, China's target of reducing the level of schistosome infection to less than 1% by 2015 may be achievable. PMID:20375361

  13. Acute Schistosomiasis in Brazilian Traveler: The Importance of Tourism in The Epidemiology of Neglected Parasitic Diseases

    PubMed Central

    Guiguet Leal, Diego Averaldo; Franco, Regina Maura Bueno; Neves, Maria Francisca; Simões, Luciana Franceschi; Bastos, Letícia Aparecida Duart; Allegretti, Silmara Marques; Zanotti-Magalhães, Eliana Maria; Magalhães, Luiz Augusto

    2012-01-01

    Parasitic infectious diseases acquired in tourist areas may pose a challenge to physicians and to travel medicine practitioners. Acute schistosomiasis may be seen in returning travelers and migrants after primary infection. This form of schistosomiasis is frequently misdiagnosed due to its temporal delay and its nonspecific presentation and might occur even in countries where the disease is endemic, such as in Brazil. The patient developed the acute phase of schistosomiasis with severe clinical manifestations. The quantitative analysis revealed the presence of 240 eggs per gram of stool. The treatment was administered with oxamniquine, and the control of cure of the patient was monitored and was favorable. The present paper aims to emphasize the importance of a detailed clinical history including information regarding travel history. PMID:22844623

  14. Acute schistosomiasis in brazilian traveler: the importance of tourism in the epidemiology of neglected parasitic diseases.

    PubMed

    Guiguet Leal, Diego Averaldo; Franco, Regina Maura Bueno; Neves, Maria Francisca; Simões, Luciana Franceschi; Bastos, Letícia Aparecida Duart; Allegretti, Silmara Marques; Zanotti-Magalhães, Eliana Maria; Magalhães, Luiz Augusto

    2012-01-01

    Parasitic infectious diseases acquired in tourist areas may pose a challenge to physicians and to travel medicine practitioners. Acute schistosomiasis may be seen in returning travelers and migrants after primary infection. This form of schistosomiasis is frequently misdiagnosed due to its temporal delay and its nonspecific presentation and might occur even in countries where the disease is endemic, such as in Brazil. The patient developed the acute phase of schistosomiasis with severe clinical manifestations. The quantitative analysis revealed the presence of 240 eggs per gram of stool. The treatment was administered with oxamniquine, and the control of cure of the patient was monitored and was favorable. The present paper aims to emphasize the importance of a detailed clinical history including information regarding travel history.

  15. Internalization of Tissue Factor-Rich Microvesicles by Platelets Occurs Independently of GPIIb-IIIa, and Involves CD36 Receptor, Serotonin Transporter and Cytoskeletal Assembly.

    PubMed

    Lopez-Vilchez, Irene; Diaz-Ricart, Maribel; Galan, Ana M; Roque, Merce; Caballo, Carolina; Molina, Patricia; White, James G; Escolar, Gines

    2016-02-01

    Platelets are important in hemostasis, but also detect particles and pathogens in the circulation. Phagocytic and endocytic activities of platelets are widely recognized; however, receptors and mechanisms involved remain poorly understood. We previously demonstrated that platelets internalize and store phospholipid microvesicles enriched in human tissue factor (TF+MVs) and that platelet-associated TF enhances thrombus formation at sites of vascular damage. Here, we investigate the mechanisms implied in the interactions of TF+MVs with platelets and the effects of specific inhibitory strategies. Aggregometry and electron microscopy were used to assess platelet activation and TF+MVs uptake. Cytoskeletal assembly and activation of phosphoinositide 3-kinase (PI3K) and RhoA were analyzed by western blot and ELISA. Exposure of platelets to TF+MVs caused reversible platelet aggregation, actin polymerization and association of contractile proteins to the cytoskeleton being maximal at 1 min. The same kinetics were observed for activation of PI3K and translocation of RhoA to the cytoskeleton. Inhibitory strategies to block glycoprotein IIb-IIIa (GPIIb-IIIa), scavenger receptor CD36, serotonin transporter (SERT) and PI3K, fully prevented platelet aggregation by TF+MVs. Ultrastructural techniques revealed that uptake of TF+MVs was efficiently prevented by anti-CD36 and SERT inhibitor, but only moderately interfered by GPIIb-IIIa blockade. We conclude that internalization of TF+MVs by platelets occurs independently of receptors related to their main hemostatic function (GPIIb-IIIa), involves the scavenger receptor CD36, SERT and engages PI3-Kinase activation and cytoskeletal assembly. CD36 and SERT appear as potential therapeutic targets to interfere with the association of TF+MVs with platelets and possibly downregulate their prothrombotic phenotype.

  16. Growth failure occurs through a decrease in insulin-like growth factor 1 which is independent of undernutrition in a rat model of colitis

    PubMed Central

    Ballinger, A; Azooz, O; El-Haj, T; Poole, S; Farthing, M

    2000-01-01

    BACKGROUND—Linear growth retardation is a frequent complication of inflammatory bowel disease in children. The precise mechanisms causing growth failure are not known.
AIMS—To determine the relative contribution of reduced calorie intake and inflammation to linear growth delay and to determine the effect of inflammation on the hypothalamic-pituitary-growth axis.
METHODS—Linear growth was assessed in prepubertal rats with trinitrobenzenesulphonic acid (TNBS) induced colitis, in healthy free feeding controls, and in a pair-fed group (i.e. healthy animals whose daily food intake was matched to the colitic group thereby distinguishing between the effects of undernutrition and inflammation).
RESULTS—Changes in length over five days in the TNBS colitis and pair-fed groups were 30% and 56%, respectively, of healthy free feeding controls. Linear growth was significantly reduced in the colitic group compared with the pair-fed group. Nutritional supplementation in the colitic group increased weight gain to control values but did not completely reverse the growth deficit. Plasma interleukin 6 (IL-6) concentrations were sixfold higher in the colitic group compared with controls. Plasma concentrations of insulin-like growth factor 1 (IGF-1) but not growth hormone (GH) were significantly lower in the colitic compared with the pair-fed group. Administration of IGF-1 to the colitic group increased plasma IGF-1 concentrations and linear growth by approximately 44-60%.
CONCLUSIONS—It seems likely that approximately 30-40% of linear growth impairment in experimental colitis occurs as a direct result of the inflammatory process which is independent of undernutrition. Inflammation acts principally at the hepatocyte/IGF-1 level to impair linear growth. Optimal growth in intestinal inflammation may only be achieved by a combination of nutritional intervention and anticytokine treatment.


Keywords: inflammatory bowel disease; TNBS colitis; growth retardation

  17. Delayed puberty in prenatally glucocorticoid administered female rats occurs independently of the hypothalamic Kiss1-Kiss1r-GnRH system.

    PubMed

    Iwasa, Takeshi; Matsuzaki, Toshiya; Murakami, Masahiro; Kinouchi, Riyo; Gereltsetseg, Ganbat; Yamamoto, Satoshi; Kuwahara, Akira; Yasui, Toshiyuki; Irahara, Minoru

    2011-04-01

    Intrauterine growth retardation (IUGR) is an important risk factor for the pathogenesis of diseases after birth. Long-lasting alterations in the structure and function of tissues and the neuroendocrine system, which are known as 'programming effects', increase the risks of these diseases. To investigate the pathophysiology of programming effects, several kinds of IUGR rodent models have been used in experiments. Sexual maturation and the onset of puberty are delayed in these models. We have previously reported that decreased action of hypothalamic kisspeptin, which is a positive regulator of GnRH, contributes to the delayed onset of puberty in undernutrition-induced IUGR rats. The aim of this study was to evaluate whether the hypothalamic Kiss1-Kiss1r-GnRH system is also altered in dexamethasone-induced IUGR rats. Compared with offspring from an untreated mother (control), offspring from a dexamethasone administered mother (DEX) showed a significant reduction in body weight throughout the experimental period (from birth to the prepubertal period) and the delayed onset of puberty. There were no significant differences between the control and DEX groups with regard to their hypothalamic Kiss1, Kiss1r, GnRH, CRH, NPY and POMC mRNA levels during the experimental period or their serum LH, FSH, or leptin concentrations at postnatal day 28 or vaginal opening (VO). Compared with the control, DEX showed significantly lower ovarian weight at postnatal day 28, but not at VO. These results suggested that the delayed onset of puberty induced by maternal dexamethasone administration would occur independently of hypothalamic Kiss1-Kiss1r-GnRH system.

  18. Schistosomiasis transmission and environmental change: a spatio-temporal analysis in Porto de Galinhas, Pernambuco - Brazil

    PubMed Central

    2012-01-01

    Background In Brazil, schistosomiasis mansoni infection is an endemic disease that mainly affects the country’s rural populations who carry out domestic and social activities in rivers and water accumulations that provide shelter for the snails of the disease. The process of rural migration to urban centers and the disorderly occupation of natural environments by these populations from endemic areas have favored expansion of schistosomiasis to locations that had been considered to be disease-free. Based on environmental changes that have occurred in consequent to an occupation and urbanization process in the locality of Porto de Galinhas, the present study sought to identify the relationship between those chances, measure by remote-sensing techniques, and establish a new endemic area for schistosomiasis on the coast of Pernambuco State - Brazil. Methods To gather prevalence data, two parasitological census surveys were conducted (2000 and 2010) using the Kato-Katz technique. Two malacological surveys were also conducted in the same years in order to define the density and infection rate of the intermediate host. Based on these data, spatial analyses were done, resulting in maps of the risk of disease transmission. To ascertain the environmental changes that have occurred at the locality, images from the QuickBird satellite were analyzed, thus resulting in land use maps. Results Over this 10-year period, the foci of schistosomiasis became more concentrated in the Salinas district. This area was considered to be at the greatest risk of schistosomiasis transmission and had the highest prevalence rates over this period. The study illustrated that this was the area most affected by the environmental changes resulting from the disorderly urbanization process, which gave rise to unsanitary environments that favored the establishment and maintenance of foci of schistosomiasis transmission, thereby consolidating the process of expansion and endemization of this

  19. Testicular Schistosomiasis Mimicking Malignancy in a Child: A Case Report.

    PubMed

    Ekenze, Sebastian O; Modekwe, Victor O; Nzegwu, Martin A; Ekpemo, Samuel C; Ezomike, Uchechukwu O

    2015-08-01

    Schistosomiasis is an important communicable disease in the developing world. However, testicular schistosomiasis is an extremely rare condition. We report a case of testicular schistosomiasis mimicking testicular tumour in a 13 year old who presented with huge unilateral testicular mass. The dilemma encountered in the diagnosis and treatment of this child is presented to highlight the need for high index of suspicion of this pathology in children with testicular mass presenting from schistosomiasis-endemic areas.

  20. Workshop report: Schistosomiasis vaccine clinical development and product characteristics.

    PubMed

    Mo, Annie X; Colley, Daniel G

    2016-02-17

    A schistosomiasis vaccine meeting was organized to evaluate the utility of a vaccine in public health programs, to discuss clinical development paths, and to define basic product characteristics for desirable vaccines to be used in the context of schistosomiasis control and elimination programs. It was concluded that clinical evaluation of a schistosomiasis vaccine is feasible with appropriate trial design and tools. Some basic Preferred Product Characteristics (PPC) for a human schistosomiasis vaccine and for a veterinary vaccine for bovine use were also proposed.

  1. Relationship between Schistosomiasis and Bladder Cancer

    PubMed Central

    Mostafa, M. H.; Sheweita, S. A.; O’Connor, P. J.

    1999-01-01

    Carcinoma of the urinary bladder is the most common malignancy in the Middle East and parts of Africa where schistosomiasis is a widespread problem. Much evidence supports the association between schistosomiasis and bladder cancer: this includes the geographical correlation between the two conditions, the distinctive patterns of gender and age at diagnosis, the clinicopathological identity of schistosome-associated bladder cancer, and extensive evidence in experimentally infected animals. Multiple factors have been suggested as causative agents in schistosome-associated bladder carcinogenesis. Of these, N-nitroso compounds appear to be of particular importance since they were found at high levels in the urine of patients with schistosomiasis-associated bladder cancer. Various strains of bacteria that can mediate nitrosation reactions leading to the formation of N-nitrosamines have been identified in the urine of subjects with schistosomiasis at higher intensities of infection than in normal subjects. In experimental schistosomiasis, the activities of carcinogen-metabolizing enzymes are increased soon after infection but are reduced again during the later chronic stages of the disease. Not only could this prolong the period of exposure to activated N-nitrosamines, but also inflammatory cells, sitmulated as a result of the infection, may induce the endogenous synthesis of N-nitrosamines as well as generating oxygen radicals. Higher than normal levels of host cell DNA damage are therefore anticipated, and they have indeed been observed in the case of alkylation damage, together with an inefficiency in the capacity of relevant enzymes to repair this damaged DNA. In experimental schistosomiasis, it was also found that endogenous levels of host cell DNA damage were related to the intensity of infection. All of these factors could contribute to an increased risk of bladder cancer in patients with schistosomiasis, and in particular, the gene changes observed may have

  2. Schistosomiasis transmission and control in China.

    PubMed

    Zou, Lan; Ruan, Shigui

    2015-03-01

    In the last 60 years, great progress has been made in controlling and preventing schistosomiasis in China. However, due to the ecosystem changes caused by the construction of the Three Gorges Dams and the South-north Water Conversion Project, the effects of climate change, the scarcity of a highly sensitive surveillance and response system, schistosomiasis is still considered as a major public health problem and is listed among the top infectious diseases in the country prioritized for control and elimination. Based on the epidemiological pattern of schistosomiasis and ecological characteristics of the vector snail, endemic areas of schistosomiasis in China were categorized into three types: (i) plain region with waterway networks, (ii) mountainous and hilly regions, and (iii) marshland and lake regions. China aims to reach the criteria of transmission control threshold of less than 1% in the lake and marshland provinces and reach transmission interruption threshold in hilly provinces of Sichuan and Yunnan by the end of 2015. The purpose of this article is to use the deterministic model proposed in our earlier study in (Chen et al., 2010) to simulate the schistosomiasis infection data from other lake and marshland provinces, including Hunan, Jiangxi and Anhui. Our simulations demonstrate that the model can reasonably mimic the schistosomiasis infection data from these lake and marshland provinces. Thus, similar control and prevention measures can be designed and proposed for these provinces. We will also try to use the model to simulate the schistosomiasis infection data from Sichuan and Yunnan provinces in the mountainous and hilly regions where cattle farming is not as popular and important as in the lake and marshland provinces and find out that different control and prevention strategies are required.

  3. [Analysis of blood glucose levels in 746 cases of schistosomiasis].

    PubMed

    Hou, An-Ming; Wu, Guo-Hua; Zhang, Gui-Lin

    2011-04-01

    The levels of blood glucose of 746 inpatients with chronic or advanced schistosomiasis were assayed last 3 years and the results were analyzed. There was no significant difference between the pure chronic or advanced schistosomiasis patients and normal population. However, there was a significant difference between the chronic or advanced schistosomiasis patients with viral hepatitis and normal population.

  4. Advances in the Diagnosis of Human Schistosomiasis

    PubMed Central

    Weerakoon, Kosala G. A. D.; Gobert, Geoffrey N.; Cai, Pengfei

    2015-01-01

    SUMMARY Schistosomiasis is a major neglected tropical disease that afflicts more than 240 million people, including many children and young adults, in the tropics and subtropics. The disease is characterized by chronic infections with significant residual morbidity and is of considerable public health importance, with substantial socioeconomic impacts on impoverished communities. Morbidity reduction and eventual elimination through integrated intervention measures are the focuses of current schistosomiasis control programs. Precise diagnosis of schistosome infections, in both mammalian and snail intermediate hosts, will play a pivotal role in achieving these goals. Nevertheless, despite extensive efforts over several decades, the search for sensitive and specific diagnostics for schistosomiasis is ongoing. Here we review the area, paying attention to earlier approaches but emphasizing recent developments in the search for new diagnostics for schistosomiasis with practical applications in the research laboratory, the clinic, and the field. Careful and rigorous validation of these assays and their cost-effectiveness will be needed, however, prior to their adoption in support of policy decisions for national public health programs aimed at the control and elimination of schistosomiasis. PMID:26224883

  5. Use of an ecologically relevant modelling approach to improve remote sensing-based schistosomiasis risk profiling.

    PubMed

    Walz, Yvonne; Wegmann, Martin; Leutner, Benjamin; Dech, Stefan; Vounatsou, Penelope; N'Goran, Eliézer K; Raso, Giovanna; Utzinger, Jürg

    2015-11-30

    Schistosomiasis is a widespread water-based disease that puts close to 800 million people at risk of infection with more than 250 million infected, mainly in sub-Saharan Africa. Transmission is governed by the spatial distribution of specific freshwater snails that act as intermediate hosts and the frequency, duration and extent of human bodies exposed to infested water sources during human water contact. Remote sensing data have been utilized for spatially explicit risk profiling of schistosomiasis. Since schistosomiasis risk profiling based on remote sensing data inherits a conceptual drawback if school-based disease prevalence data are directly related to the remote sensing measurements extracted at the location of the school, because the disease transmission usually does not exactly occur at the school, we took the local environment around the schools into account by explicitly linking ecologically relevant environmental information of potential disease transmission sites to survey measurements of disease prevalence. Our models were validated at two sites with different landscapes in Côte d'Ivoire using high- and moderate-resolution remote sensing data based on random forest and partial least squares regression. We found that the ecologically relevant modelling approach explained up to 70% of the variation in Schistosoma infection prevalence and performed better compared to a purely pixel-based modelling approach. Furthermore, our study showed that model performance increased as a function of enlarging the school catchment area, confirming the hypothesis that suitable environments for schistosomiasis transmission rarely occur at the location of survey measurements.

  6. Recent situation of schistosomiasis in Indonesia.

    PubMed

    Izhar, Ali; Sinaga, R M; Sudomo, M; Wardiyo, N D

    2002-05-01

    Schistosomiasis in Indonesia is limited to two very isolated areas, the Napu and Lindu valleys, in the province of Central Sulawesi. The disease was initially found in 1937 in the village of Tomado. In 1940, a study on schistosomiasis in the Lake Lindu area was initiated and an infection rate of 56% among the people in the three villages of Anca, Tomado and Langko was found. Before a comprehensive control programme was initiated, the infection rate among the population of approximately 4000 people in the Napu valley was very high, e.g. 72% in the village of Winowanga. In 1982, more coordinated and intensive schistosomiasis control measures in the Napu and Lindu valleys were initiated. The average infection rate after control measures were greatly decreased-in Napu valley it was 1.83%, while in Lindu valley it was 0.46%, in 1999. The control approaches can be described over five phases, from 1982 to 1986, up to 1998 to present. In 1998, an agreement between the Government of Indonesia and the Asian Development Bank was signed to develop the schistosomiasis endemic areas of Central Sulawesi into a better socio-economic condition. The objectives of the project are not only to control schistosomiasis, but mainly to protect the National Park which is located between the Lindu and Napu valleys. It is an integrated project named 'Central Sulawesi Integrated Area Development and Conservation Project' and many relevant sectors have been involved in the implementation of this project for the development of the area, including control of schistosomiasis. The implementation of the integrated project started in 1999.

  7. Potential of Sentinel Satellites for Schistosomiasis Monitoring

    NASA Astrophysics Data System (ADS)

    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

  8. Liver collagen synthesis in murine schistosomiasis.

    PubMed Central

    Dunn, M A; Rojkind, M; Warren, K S; Hait, P K; Rifas, L; Seifter, S

    1977-01-01

    Collagen synthesis was measured in liver slices obtained from mice with hepatosplenic schistosomiasis. Enlarged fibrotic livers from these mice contained 20 times more collagen than normal. This model of hepatic fibrosis results from an inflammatory granulomatous host response to Schistosoma mansoni ova in portal tracts, rather than from direct lover cell injury as with carbon tetrachloride-induced liver fibrosis. Collagen synthesis, as measured by the formation of labeled protein-bound hydroxyproline, occurred in granulomas isolated from fibrotic livers. Labeled collagen that cochromatographed with type I collagen was extracted with neutral salt solution from liver slices incubated with labeled proline. The free proline pool of the liver was doubled in infected mice; coordinately, liver slices from these animals showed maximal collagen production when the concentration of free proline in the medium was raised to 0.4 mM, the same level measured in the fibrotic livers. Under such conditions, collagen synthesis was at a rate equivalent to the formation of 5.4 nmol of protein-bound hydroxyproline per g liver in 6 h. In comparative incubations in medium containing 0.2 mM proline, fibrotic liver slices produced 16-fold more collagen than normal slices. The proline analogue, L-azetidine 2-carboxylic acid, effectively inhibited synthesis of labeled collagen by fibrotic liver slices. These studies show the synthesis of collagen in a reproducible animal model of the most prevalent form of human liver fibrosis. Difinitition of the controlling factors in this system is of interest for the general problem of fibrosis produced by immunological responses. Images PMID:845255

  9. Social Learning in the Real-World: ‘Over-Imitation’ Occurs in Both Children and Adults Unaware of Participation in an Experiment and Independently of Social Interaction

    PubMed Central

    Whiten, Andrew; Allan, Gillian; Devlin, Siobahn; Kseib, Natalie; Raw, Nicola; McGuigan, Nicola

    2016-01-01

    The current study avoided the typical laboratory context to determine instead whether over-imitation—the disposition to copy even visibly, causally unnecessary actions—occurs in a real-world context in which participants are unaware of being in an experiment. We disguised a puzzle-box task as an interactive item available to the public within a science engagement zone of Edinburgh Zoo. As a member of the public approached, a confederate acting as a zoo visitor retrieved a reward from the box using a sequence of actions containing both causally relevant and irrelevant elements. Despite the absence of intentional demonstration, or social pressure to copy, a majority of both child and even adult observers included all causally irrelevant actions in their reproduction. This occurred even though causal irrelevance appeared manifest because of the transparency of the puzzle-box. That over-imitation occurred so readily in a naturalistic context, devoid of social interaction and pressure, suggests that humans are opportunistic social learners throughout the lifespan, copying the actions of other individuals even when these actions are not intentionally demonstrated, and their causal significance is not readily apparent. The disposition to copy comprehensively, even when a mere onlooker, likely provides humans, irrespective of their age, with a powerful mechanism to extract maximal information from the social environment. PMID:27466806

  10. Social Learning in the Real-World: 'Over-Imitation' Occurs in Both Children and Adults Unaware of Participation in an Experiment and Independently of Social Interaction.

    PubMed

    Whiten, Andrew; Allan, Gillian; Devlin, Siobahn; Kseib, Natalie; Raw, Nicola; McGuigan, Nicola

    2016-01-01

    The current study avoided the typical laboratory context to determine instead whether over-imitation-the disposition to copy even visibly, causally unnecessary actions-occurs in a real-world context in which participants are unaware of being in an experiment. We disguised a puzzle-box task as an interactive item available to the public within a science engagement zone of Edinburgh Zoo. As a member of the public approached, a confederate acting as a zoo visitor retrieved a reward from the box using a sequence of actions containing both causally relevant and irrelevant elements. Despite the absence of intentional demonstration, or social pressure to copy, a majority of both child and even adult observers included all causally irrelevant actions in their reproduction. This occurred even though causal irrelevance appeared manifest because of the transparency of the puzzle-box. That over-imitation occurred so readily in a naturalistic context, devoid of social interaction and pressure, suggests that humans are opportunistic social learners throughout the lifespan, copying the actions of other individuals even when these actions are not intentionally demonstrated, and their causal significance is not readily apparent. The disposition to copy comprehensively, even when a mere onlooker, likely provides humans, irrespective of their age, with a powerful mechanism to extract maximal information from the social environment.

  11. Schistosomiasis: The World's Number One Health Problem

    ERIC Educational Resources Information Center

    Mallon, Elizabeth J.

    1977-01-01

    Provides an informative discussion of the disease called schistosomiasis. The discussion covers environmental factors contributing to the disease, its symptoms, the disease organism and its vectors, and treatment of the disease. The author points out the need for water and soil pollution control in disease prone areas. (MR)

  12. Dynamics of spatial clustering of schistosomiasis in the Yangtze River Valley at the end of and following the World Bank Loan Project.

    PubMed

    Hu, Yi; Xiong, Chenglong; Zhang, Zhijie; Luo, Can; Ward, Michael; Gao, Jie; Zhang, Lijuan; Jiang, Qingwu

    2014-06-01

    The 10-year (1992-2001) World Bank Loan Project (WBLP) contributed greatly to schistosomiasis control in China. However, the re-emergence of schistosomiasis in recent years challenged the long-term progress of the WBLP strategy. In order to gain insight in the long-term progress of the WBLP, the spatial pattern of the epidemic was investigated in the Yangtze River Valley between 1999-2001 and 2007-2008. Two spatial cluster methods were jointly used to identify spatial clusters of cases. The magnitude and number of clusters varied during 1999-2001. It was found that prevalence of schistosomiasis had been greatly reduced and maintained at a low level during 2007-2008, with little change. Besides, spatial clusters most frequently occurred within 16 counties in the Dongting Lake region and within 5 counties in the Poyang Lake region. These findings precisely pointed out the prior places for future public health planning and resource allocation of schistosomiasis.

  13. Topoisomerase II– and Condensin-Dependent Breakage of MEC1ATR-Sensitive Fragile Sites Occurs Independently of Spindle Tension, Anaphase, or Cytokinesis

    PubMed Central

    Hashash, Nadia; Johnson, Anthony L.; Cha, Rita S.

    2012-01-01

    Fragile sites are loci of recurrent chromosome breakage in the genome. They are found in organisms ranging from bacteria to humans and are implicated in genome instability, evolution, and cancer. In budding yeast, inactivation of Mec1, a homolog of mammalian ATR, leads to chromosome breakage at fragile sites referred to as replication slow zones (RSZs). RSZs are proposed to be homologous to mammalian common fragile sites (CFSs) whose stability is regulated by ATR. Perturbation during S phase, leading to elevated levels of stalled replication forks, is necessary but not sufficient for chromosome breakage at RSZs or CFSs. To address the nature of additional event(s) required for the break formation, we examined involvement of the currently known or implicated mechanisms of endogenous chromosome breakage, including errors in replication fork restart, premature mitotic chromosome condensation, spindle tension, anaphase, and cytokinesis. Results revealed that chromosome breakage at RSZs is independent of the RAD52 epistasis group genes and of TOP3, SGS1, SRS2, MMS4, or MUS81, indicating that homologous recombination and other recombination-related processes associated with replication fork restart are unlikely to be involved. We also found spindle force, anaphase, or cytokinesis to be dispensable. RSZ breakage, however, required genes encoding condensin subunits (YCG1, YSC4) and topoisomerase II (TOP2). We propose that chromosome break formation at RSZs following Mec1 inactivation, a model for mammalian fragile site breakage, is mediated by internal chromosomal stress generated during mitotic chromosome condensation. PMID:23133392

  14. [Natural environment and schistosomiasis transmission in Poyang Lake region].

    PubMed

    Lv, Shang-Biao; Lin, Dan-Dan

    2014-10-01

    Schistosomiasis is closely related to natural environmental factors. The changes of environmental factors, such as temperature, hydrology, vegetation, soil etc., all impact the scope and extent of schistosomiasis transmission. Poyang Lake is the largest freshwater lake and one of the major endemic areas with schistosomiasis in China. With global warming, the implementation of the Three Gorges Dam operation, and the Poyang Lake Ecological Economic Planning, the natural environment in Poyang Lake area has been and will continue to change, especially, the water environment and climate environment, which are more closely related to the schistosomiasis transmission. These changes, to some extent, have affected and will continue to affect the prevalence and transmission of schistosomiasis. This article reviews the relationship between the natural environment and its changes and schistosomiasis transmission in the Poyang Lake region.

  15. Macrophage-derived Hedgehog Ligands Promotes Fibrogenic and Angiogenic Responses in Human Schistosomiasis mansoni

    PubMed Central

    Pereira, Thiago A.; Xie, Guanhua; Choi, Steve S.; Syn, Wing-Kin; Voieta, Izabela; Lu, Jiuyi; Chan, Isaac S.; Swiderska, Marzena; Amaral, Kirsten B.; Antunes, Carlos Maurício; Secor, William E.; Witek, Rafal P.; Lambertucci, José Roberto; Pereira, Fausto L.; Diehl, Anna Mae

    2012-01-01

    Background Schistosomiasis mansoni is a major cause of portal fibrosis and portal hypertension. The Hedgehog pathway regulates fibrogenic repair in some types of liver injury. Aims Determine if Hedgehog-pathway activation occurs during fibrosis progression in schistosomiasis and to determine if macrophage-related mechanisms are involved. Methods Immunohistochemistry was used to characterize the cells that generate and respond to Hedgehog ligands in 28 liver biopsies from patients with different grades of schistosomiasis fibrosis staged by ultrasound. Cultured macrophages (RAW264.7 and primary rat Kupffer cells) and primary rat liver sinusoidal endothelial cells (LSEC) were treated with schistosome egg antigen (SEA) and evaluated by qRT-PCR. Inhibition of the Hedgehog-pathway was used to investigate its role in alternative activation of macrophages (M2) and vascular tube formation. Results Patients with schistosomiasis expressed more ligands (Shh and Ihh) and target genes (Patched and Gli2) than healthy individuals. Activated LSEC and myofibroblasts were Hedgehog-responsive (Gli2(+)) and accumulated in parallel with fibrosis stage (p<0.05). Double IHC for Ihh/CD68 showed that Ihh(+) cells were macrophages. In vitro studies demonstrated that SEA stimulated macrophages to express Ihh and Shh mRNA (p<0.05). Conditioned media from such macrophages induced luciferase production by Shh-LightII cells (p<0.001) and Hedgehog inhibitors blocked this effect (p<0.001). SEA-treated macrophages also up-regulated their own expression of M2 markers, and Hh-pathway inhibitors abrogated this response (p<0.01). Inhibition of the Hedgehog pathway in LSEC blocked SEA-induced migration and tube formation. Conclusion SEA stimulates liver macrophages to produce Hh-ligands, which promote alternative activation of macrophages, fibrogenesis, and vascular remodeling in schistosomiasis. PMID:23121638

  16. The NIH-NIAID Schistosomiasis Resource Center at the Biomedical Research Institute: Molecular Redux

    PubMed Central

    Cody, James J.; Ittiprasert, Wannaporn; Miller, André N.; Henein, Lucie; Mentink-Kane, Margaret M.; Hsieh, Michael H.

    2016-01-01

    Schistosomiasis remains a health burden in many parts of the world. The complex life cycle of Schistosoma parasites and the economic and societal conditions present in endemic areas make the prospect of eradication unlikely in the foreseeable future. Continued and vigorous research efforts must therefore be directed at this disease, particularly since only a single World Health Organization (WHO)-approved drug is available for treatment. The National Institutes of Health (NIH)–National Institute of Allergy and Infectious Diseases (NIAID) Schistosomiasis Resource Center (SRC) at the Biomedical Research Institute provides investigators with the critical raw materials needed to carry out this important research. The SRC makes available, free of charge (including international shipping costs), not only infected host organisms but also a wide array of molecular reagents derived from all life stages of each of the three main human schistosome parasites. As the field of schistosomiasis research rapidly advances, it is likely to become increasingly reliant on omics, transgenics, epigenetics, and microbiome-related research approaches. The SRC has and will continue to monitor and contribute to advances in the field in order to support these research efforts with an expanding array of molecular reagents. In addition to providing investigators with source materials, the SRC has expanded its educational mission by offering a molecular techniques training course and has recently organized an international schistosomiasis-focused meeting. This review provides an overview of the materials and services that are available at the SRC for schistosomiasis researchers, with a focus on updates that have occurred since the original overview in 2008. PMID:27764112

  17. Versatile reporter systems show that transactivation by human T-cell leukemia virus type 1 Tax occurs independently of chromatin remodeling factor BRG1.

    PubMed

    Zhang, Ling; Liu, Meihong; Merling, Randall; Giam, Chou-Zen

    2006-08-01

    Potent activation of human T-cell leukemia virus type 1 (HTLV-1) gene expression is mediated by the virus-encoded transactivator protein Tax and three imperfect 21-bp repeats in the viral long terminal repeats. Each 21-bp repeat contains a cAMP-responsive-element core flanked by 5' G-rich and 3' C-rich sequences. Tax alone does not bind DNA. Rather, it interacts with basic domain-leucine zipper transcription factors CREB and ATF-1 to form ternary complexes with the 21-bp repeats. In the context of the ternary complexes, Tax contacts the G/C-rich sequences and recruits transcriptional coactivators CREB-binding protein (CBP)/p300 to effect potent transcriptional activation. Using an easily transduced and chromosomally integrated reporter system derived from a self-inactivating lentivirus vector, we showed in a BRG1- and BRM1-deficient adrenal carcinoma cell line, SW-13, that Tax- and 21-bp repeat-mediated transactivation does not require BRG1 or BRM1 and is not enhanced by BRG1. With a similar reporter system, we further demonstrated that Tax- and tumor necrosis factor alpha-induced NF-kappaB activation occurs readily in SW-13 cells in the absence of BRG1 and BRM1. These results suggest that the assembly of stable multiprotein complexes containing Tax, CREB/ATF-1, and CBP/p300 on the 21-bp repeats is the principal mechanism employed by Tax to preclude nucleosome formation at the HTLV-1 enhancer/promoter. This most likely bypasses the need for BRG1-containing chromatin-remodeling complexes. Likewise, recruitment of CBP/p300 by NF-kappaB may be sufficient to disrupt histone-DNA interaction for the initiation of transcription.

  18. Airway Hyperresponsiveness in Asthma Model Occurs Independently of Secretion of β1 Integrins in Airway Wall and Focal Adhesions Proteins Down Regulation.

    PubMed

    Álvarez-Santos, Mayra; Carbajal, Verónica; Tellez-Jiménez, Olivia; Martínez-Cordero, Erasmo; Ruiz, Victor; Hernández-Pando, Rogelio; Lascurain, Ricardo; Santibañez-Salgado, Alfredo; Bazan-Perkins, Blanca

    2016-10-01

    The extracellular domains of some membrane proteins can be shed from the cell. A similar phenomenon occurs with β1 integrins (α1β1 and α2β1) in guinea pig. The putative role of β1 integrin subunit alterations due to shedding in airway smooth muscle (ASM) in an allergic asthma model was evaluated. Guinea pigs were sensitized and challenged with antigen. Antigenic challenges induced bronchoobstruction and hyperresponsiveness at the third antigenic challenge. Immunohistochemistry and immunoelectronmicroscopy studies showed that the cytosolic and extracellular domains of the β1 integrin subunit shared the same distribution in airway structures in both groups. Various polypeptides with similar molecular weights were detected with both the cytosolic and extracellular β1 integrin subunit antibodies in isolated airway myocytes and the connective tissue that surrounds the ASM bundle. Flow cytometry and Western blot studies showed that the expression of cytosolic and extracellular β1 integrin subunit domains in ASM was similar between groups. An increment of ITGB1 mRNA in ASM was observed in the asthma model group. RACE-PCR of ITGB1 in ASM did not show splicing variants. The expression levels of integrin-linked kinase (ILK) and paxillin diminished in the asthma model, but not talin. The levels of phosphorylation of myosin phosphatase target subunit 1 (MYPT1) at Thr(696) increased in asthma model. Our work suggests that β1 integrin is secreted in guinea pig airway wall. This secretion is not altered in asthma model; nevertheless, β1 integrin cytodomain assembly proteins in focal cell adhesions in which ILK and paxillin are involved are altered in asthma model. J. Cell. Biochem. 117: 2385-2396, 2016. © 2016 Wiley Periodicals, Inc.

  19. [Implementation of precision control to achieve the goal of schistosomiasis elimination in China].

    PubMed

    Zhou, Xiao-nong

    2016-02-01

    The integrated strategy for schistosomiasis control with focus on infectious source control, which has been implemented since 2004, accelerated the progress towards schistosomiasis control in China, and achieved transmission control of the disease across the country by the end of 2015, which achieved the overall objective of the Mid- and Long-term National Plan for Prevention and Control of Schistosomiasis (2004-2015) on schedule. Then, the goal of schistosomiasis elimination by 2025 was proposed in China in 2014. To achieve this new goal on schedule, we have to address the key issues, and implement precision control measures with more precise identification of control targets, so that we are able to completely eradicate the potential factors leading to resurgence of schistosomiasis transmission and enable the achievement of schistosomiasis elimination on schedule. Precision schistosomiasis control, a theoretical innovation of precision medicine in schistosomiasis control, will provide new insights into schistosomiasis control based on the conception of precision medicine. This paper describes the definition, interventions and the role of precision schistosomiasis control in the elimination of schistosomiasis in China, and demonstrates that sustainable improvement of professionals and integrated control capability at grass-root level is a prerequisite to the implementation of schistosomiasis control, precision schistosomiasis control is a key to the further implementation of the integrated strategy for schistosomiasis control with focus on infectious source control, and precision schistosomiasis control is a guarantee of curing schistosomiasis patients and implementing schistosomiasis control program and interventions.

  20. Health Access Livelihood Framework Reveals Potential Barriers in the Control of Schistosomiasis in the Dongting Lake Area of Hunan Province, China

    PubMed Central

    McManus, Donald P.; Raso, Giovanna; Utzinger, Jürg; Xiao, Shui-Yuan; Yu, Dong-Bao; Zhao, Zheng-Yuan; Li, Yue-Sheng

    2013-01-01

    Background Access to health care is a major requirement in improving health and fostering socioeconomic development. In the People's Republic of China (P.R. China), considerable changes have occurred in the social, economic, and health systems with a shift from a centrally planned to a socialist market economy. This brought about great benefits and new challenges, particularly for vertical disease control programs, including schistosomiasis. We explored systemic barriers in access to equitable and effective control of schistosomiasis. Methodology Between August 2002 and February 2003, 66 interviews with staff from anti-schistosomiasis control stations and six focus group discussions with health personnel were conducted in the Dongting Lake area, Hunan Province. Additionally, 79 patients with advanced schistosomiasis japonica were interviewed. The health access livelihood framework was utilized to examine availability, accessibility, affordability, adequacy, and acceptability of schistosomiasis-related health care. Principal Findings We found sufficient availability of infrastructure and human resources at most control stations. Many patients with advanced schistosomiasis resided in non-endemic or moderately endemic areas, however, with poor accessibility to disease-specific knowledge and specialized health services. Moreover, none of the patients interviewed had any form of health insurance, resulting in high out-of-pocket expenditure or unaffordable care. Reports on the adequacy and acceptability of care were mixed. Conclusions/Significance There is a need to strengthen health awareness and schistosomiasis surveillance in post-transmission control settings, as well as to reduce diagnostic and treatment costs. Further studies are needed to gain a multi-layered, in-depth understanding of remaining barriers, so that the ultimate goal of schistosomiasis elimination in P.R. China can be reached. PMID:23936580

  1. Data management in schistosomiasis control programmes.

    PubMed

    Dixon, H G

    1986-06-01

    Adequate data recording, processing, analysis and evaluation are all components of data management within schistosomiasis control programmes oriented towards reduction of morbidity. Without data management, the response to operational questions will remain subjective and vague. Different types of data related to the population and the environment are reviewed. Examples of data format and presentation are given. The importance of data management for proper short and long term evaluation of control measures is emphasized.

  2. Testing of Compounds for Efficacy Against Schistosomiasis

    DTIC Science & Technology

    1988-08-25

    infections in humans. These are praziquantel , active against all species of schistosomes infective to man; oxamniquine, active against one species of...that strains of S. haematobium resistant to metrifonate have emerged [8]. This leaves only one antischistosomal agent, praziquantel , with minimal...side effects for use in treatment of schistosomiasis at present. Studies to determine if praziquantel is capable of causing drug-resistant schistosomes

  3. Water-based interventions for schistosomiasis control

    PubMed Central

    Evan Secor, William

    2014-01-01

    Mass drug administration with praziquantel is the mainstay of programs for the control of schistosomiasis morbidity. However, there is a growing recognition that treatment alone will not be sufficient for eventually effecting elimination and that additional measures will be required to interrupt transmission. In the absence of a safe and an effective vaccine for human schistosomiasis, the strategies to reduce infection levels will necessarily involve some interventions that affect the water-related stages of the schistosome life cycle: by reducing exposure to infectious water, by moderating availability of the intermediate snail host, or by decreasing contamination of water with egg-containing excreta. While much research on the importance of water on schistosomiasis has been performed, advances in these areas have perhaps languished with the ready availability of a cost-effective treatment. As some endemic areas near a shift to an elimination goal, a better understanding of water-based interventions that can be used alone or in concert with treatment will be needed. Reinvigoration of laboratory, field, and human behavioral aspects of this research now will ensure that the appropriate strategies are available by the time their implementation becomes necessary. PMID:25175875

  4. New research tools for urogenital schistosomiasis.

    PubMed

    Rinaldi, Gabriel; Young, Neil D; Honeycutt, Jared D; Brindley, Paul J; Gasser, Robin B; Hsieh, Michael H

    2015-03-15

    Approximately 200,000,000 people have schistosomiasis (schistosome infection). Among the schistosomes, Schistosoma haematobium is responsible for the most infections, which are present in 110 million people globally, mostly in sub-Saharan Africa. This pathogen causes an astonishing breadth of sequelae: hematuria, anemia, dysuria, stunting, uremia, bladder cancer, urosepsis, and human immunodeficiency virus coinfection. Refined estimates of the impact of schistosomiasis on quality of life suggest that it rivals malaria. Despite S. haematobium's importance, relevant research has lagged. Here, we review advances that will deepen knowledge of S. haematobium. Three sets of breakthroughs will accelerate discoveries in the pathogenesis of urogenital schistosomiasis (UGS): (1) comparative genomics, (2) the development of functional genomic tools, and (3) the use of animal models to explore S. haematobium-host interactions. Comparative genomics for S. haematobium is feasible, given the sequencing of multiple schistosome genomes. Features of the S. haematobium genome that are conserved among platyhelminth species and others that are unique to S. haematobium may provide novel diagnostic and drug targets for UGS. Although there are technical hurdles, the integrated use of these approaches can elucidate host-pathogen interactions during this infection and can inform the development of techniques for investigating schistosomes in their human and snail hosts and the development of therapeutics and vaccines for the control of UGS.

  5. Current Status of Vaccines for Schistosomiasis

    PubMed Central

    McManus, Donald P.; Loukas, Alex

    2008-01-01

    Schistosomiasis, caused by trematode blood flukes of the genus Schistosoma, is recognized as the most important human helminth infection in terms of morbidity and mortality. Infection follows direct contact with freshwater harboring free-swimming larval (cercaria) forms of the parasite. Despite the existence of the highly effective antischistosome drug praziquantel (PZQ), schistosomiasis is spreading into new areas, and although it is the cornerstone of current control programs, PZQ chemotherapy does have limitations. In particular, mass treatment does not prevent reinfection. Furthermore, there is increasing concern about the development of parasite resistance to PZQ. Consequently, vaccine strategies represent an essential component for the future control of schistosomiasis as an adjunct to chemotherapy. An improved understanding of the immune response to schistosome infection, both in animal models and in humans, suggests that development of a vaccine may be possible. This review considers aspects of antischistosome protective immunity that are important in the context of vaccine development. The current status in the development of vaccines against the African (Schistosoma mansoni and S. haematobium) and Asian (S. japonicum) schistosomes is then discussed, as are new approaches that may improve the efficacy of available vaccines and aid in the identification of new targets for immune attack. PMID:18202444

  6. Germline Defects Caused by Smed-boule RNA-Interference Reveal That Egg Capsule Deposition Occurs Independently of Fertilization, Ovulation, Mating, or the Presence of Gametes in Planarian Flatworms

    PubMed Central

    Steiner, Jessica Kathryne; Tasaki, Junichi; Rouhana, Labib

    2016-01-01

    Few animals are known to lay eggs in the absence of ovulation or copulation, as it is presumably energetically wasteful and subjected to negative selection. Characterization of Smed-boule, a member of the DAZ family of germline RNA-binding proteins, revealed that egg capsule (or capsule) production and deposition occurs independently of the presence of gametes in the planarian flatworm Schmidtea mediterranea. Reduction of Smed-boule expression by RNA-interference (RNAi) causes ablation of spermatogonial stem cells and the inability of ovarian germline stem cells to undergo oogenesis. Although animals subjected to Smed-boule RNAi lose their gametes and become sterile, they continue to lay egg capsules. Production of sterile capsules is even observed in virgin Smed-boule(RNAi) and control planarians maintained in complete isolation, demonstrating that egg production in S. mediterranea occurs independently of ovulation, fertilization, or mating. Evidence suggests that this is a conserved feature amongst Platyhelminthes, and therefore relevant to the pathology and dissemination of parasitic flatworms. These findings demonstrate that Smed-boule functions at different stages during male and female germline stem cell development, and also demonstrate that egg capsule production by planarian flatworms occurs independently of signals produced by mating or ova. PMID:27149082

  7. Germline Defects Caused by Smed-boule RNA-Interference Reveal That Egg Capsule Deposition Occurs Independently of Fertilization, Ovulation, Mating, or the Presence of Gametes in Planarian Flatworms.

    PubMed

    Steiner, Jessica Kathryne; Tasaki, Junichi; Rouhana, Labib

    2016-05-01

    Few animals are known to lay eggs in the absence of ovulation or copulation, as it is presumably energetically wasteful and subjected to negative selection. Characterization of Smed-boule, a member of the DAZ family of germline RNA-binding proteins, revealed that egg capsule (or capsule) production and deposition occurs independently of the presence of gametes in the planarian flatworm Schmidtea mediterranea. Reduction of Smed-boule expression by RNA-interference (RNAi) causes ablation of spermatogonial stem cells and the inability of ovarian germline stem cells to undergo oogenesis. Although animals subjected to Smed-boule RNAi lose their gametes and become sterile, they continue to lay egg capsules. Production of sterile capsules is even observed in virgin Smed-boule(RNAi) and control planarians maintained in complete isolation, demonstrating that egg production in S. mediterranea occurs independently of ovulation, fertilization, or mating. Evidence suggests that this is a conserved feature amongst Platyhelminthes, and therefore relevant to the pathology and dissemination of parasitic flatworms. These findings demonstrate that Smed-boule functions at different stages during male and female germline stem cell development, and also demonstrate that egg capsule production by planarian flatworms occurs independently of signals produced by mating or ova.

  8. Role of microRNAs in schistosomes and schistosomiasis.

    PubMed

    Zhu, Lihui; Liu, Jinming; Cheng, Guofeng

    2014-01-01

    Schistosomes, a class of parasitic trematode worms, cause schistosomiasis. Accumulating evidence suggests that microRNAs (miRNAs)-small, non-coding RNAs that are known to play critical regulatory roles in many organisms-may be involved in schistosome development and sexual maturation, as well as the pathogenesis of schistosomiasis. Schistosoma miRNAs, such as Bantam and miR-10, may be involved in the pathological processes of schistosomiasis, and recent studies suggest that schistosome-specific miRNAs (e.g., Bantam, miR-3479-3p) in the bloodstream of a final host could be used as biomarkers for schistosomiasis diagnosis. Furthermore, aberrant miRNAs, such as miR-223 and miR-454, can be produced by a host in response to schistosome infection, and these miRNAs may contribute to the pathogenesis of schistosomiasis-associated liver injury. Here, we summarize recent progress evaluating the relationship between schistosome miRNAs and schistosomiasis and discuss how these miRNAs can mediate the pathogenesis of schistosomiasis and be used as biomarkers for schistosomiasis diagnosis.

  9. Cutaneous immediate and late phase reactions to schistosomin in schistosomiasis patients.

    PubMed

    Marotto, P C; Michalany, N S; Vilela, M P; Mendes, N F; Mendes, E

    1995-01-01

    Cutaneous immediate and late phase reactions (LPR) to schistosomin were studied in 29 patients with schistosomiasis mansoni. In 12 of these patients, the determination of total and specific serum IgE by immunoenzymatic method against schistosome antigen was carried out using serum samples obtained on the same day as the cutaneous tests. Skin biopsies were taken from 4 typical LPRs. Immediate reactions occurred in all except one and LPRs in 12 (41.3%). Patients with positive cutaneous reactions had highe levels of specific serum IgE against schistosome antigen. Histopathological studies showed a moderate exudate consisting mainly of neutrophils (60%) and eosinophils (40%). LPRs in schistosomiasis have the same characteristics reported in the medical literature in relation to time of appearance, morphology and histopathology. The immunopathogenic role played by LPRs in the patients remains to be clarified.

  10. Non-necrotizing colonic granuloma induced by schistosomiasis

    PubMed Central

    Swe, Thein; Baqui, AAMA; Naing, Akari Thein; Baqui, Tajruba; Sherigar, Jagannath; Mansour, Mohamed

    2016-01-01

    Schistosomiasis is an important parasitic disease with various clinical presentations caused by trematode blood flukes. It can present with asymptomatic, chronic colonic ulcerations, strictures, or inflammatory mass causing bowel obstruction. Intestinal polyps are uncommon and induced by antigens released from the schistosome eggs that trigger a cell-mediated inflammatory response with granuloma formation involving T cells, macrophages, and necrosis. This is very relevant while evaluating chronic intermittent gastrointestinal symptoms and eosinophilia in an immigrant patient from endemic areas of schistosomiasis. Here, we describe a case of chronic intestinal schistosomiasis which was found to have schistosomiasis-induced colonic polyp with non-necrotizing granuloma. With increase in immigrant population from the endemic areas of schistosomiasis in the United States, physicians should be aware of this disease and its various manifestations. Gastroenterologist should keep this as one of the differentials for colonic polyps. Diagnosis and treatment in time prevents further progression of the disease and its complications. PMID:27987283

  11. Transcriptional Profiling of the Bladder in Urogenital Schistosomiasis Reveals Pathways of Inflammatory Fibrosis and Urothelial Compromise

    PubMed Central

    Ray, Debalina; Nelson, Tyrrell A.; Fu, Chi-Ling; Patel, Shailja; Gong, Diana N.; Odegaard, Justin I.; Hsieh, Michael H.

    2012-01-01

    Urogenital schistosomiasis, chronic infection by Schistosoma haematobium, affects 112 million people worldwide. S. haematobium worm oviposition in the bladder wall leads to granulomatous inflammation, fibrosis, and egg expulsion into the urine. Despite the global impact of urogenital schistosomiasis, basic understanding of the associated pathologic mechanisms has been incomplete due to the lack of suitable animal models. We leveraged our recently developed mouse model of urogenital schistosomiasis to perform the first-ever profiling of the early molecular events that occur in the bladder in response to the introduction of S. haematobium eggs. Microarray analysis of bladders revealed rapid, differential transcription of large numbers of genes, peaking three weeks post-egg administration. Many differentially transcribed genes were related to the canonical Type 2 anti-schistosomal immune response, as reflected by the development of egg-based bladder granulomata. Numerous collagen and metalloproteinase genes were differentially transcribed over time, revealing complex remodeling and fibrosis of the bladder that was confirmed by Masson's Trichrome staining. Multiple genes implicated in carcinogenesis pathways, including vascular endothelial growth factor-, oncogene-, and mammary tumor-related genes, were differentially transcribed in egg-injected bladders. Surprisingly, junctional adhesion molecule, claudin and uroplakin genes, key components for maintaining the urothelial barrier, were globally suppressed after bladder exposure to eggs. This occurred in the setting of urothelial hyperplasia and egg shedding in urine. Thus, S. haematobium egg expulsion is associated with intricate modulation of the urothelial barrier on the cellular and molecular level. Taken together, our findings have important implications for understanding host-parasite interactions and carcinogenesis in urogenital schistosomiasis, and may provide clues for novel therapeutic strategies. PMID

  12. Geographical information system and predictive risk maps of urinary schistosomiasis in Ogun State, Nigeria

    PubMed Central

    Ekpo, Uwem F; Mafiana, Chiedu F; Adeofun, Clement O; Solarin, Adewale RT; Idowu, Adewumi B

    2008-01-01

    Background The control of urinary schistosomiasis in Ogun State, Nigeria remains inert due to lack of reliable data on the geographical distribution of the disease and the population at risk. To help in developing a control programme, delineating areas of risk, geographical information system and remotely sensed environmental images were used to developed predictive risk maps of the probability of occurrence of the disease and quantify the risk for infection in Ogun State, Nigeria. Methods Infection data used were derived from carefully validated morbidity questionnaires among primary school children in 2001–2002, in which school children were asked among other questions if they have experienced "blood in urine" or urinary schistosomiasis. The infection data from 1,092 schools together with remotely sensed environmental data such as rainfall, vegetation, temperature, soil-types, altitude and land cover were analysis using binary logistic regression models to identify environmental features that influence the spatial distribution of the disease. The final regression equations were then used in Arc View 3.2a GIS software to generate predictive risk maps of the distribution of the disease and population at risk in the state. Results Logistic regression analysis shows that the only significant environmental variable in predicting the presence and absence of urinary schistosomiasis in any area of the State was Land Surface Temperature (LST) (B = 0.308, p = 0.013). While LST (B = -0.478, p = 0.035), rainfall (B = -0.006, p = 0.0005), ferric luvisols (B = 0.539, p = 0.274), dystric nitosols (B = 0.133, p = 0.769) and pellic vertisols (B = 1.386, p = 0.008) soils types were the final variables in the model for predicting the probability of an area having an infection prevalence equivalent to or more than 50%. The two predictive risk maps suggest that urinary schistosomiasis is widely distributed and occurring in all the Local Government Areas (LGAs) in State. The high

  13. [Discussion on abilities for a leader of station of schistosomiasis prevention and control at primary level].

    PubMed

    Tao, Bo; Zhang, Zhi-Jie

    2012-08-01

    Based on the actual situation of schistosomiasis prevention and control at the primary level and from the point of a leader of the local station of schistosomiasis prevention and control, we put forward the practical problems existed in the process of schistosomiasis-related work and the corresponding solutions. What responsibilities and abilities that a leader of the station of schistosomiasis prevention and control should have are discussed and some suggestions are also given for serving the work of schistosomiasis prevention and control.

  14. Schistosomiasis in the Democratic Republic of Congo: a literature review.

    PubMed

    Madinga, Joule; Linsuke, Sylvie; Mpabanzi, Liliane; Meurs, Lynn; Kanobana, Kirezi; Speybroeck, Niko; Lutumba, Pascal; Polman, Katja

    2015-11-19

    Schistosomiasis is a poverty-related parasitic infection, leading to chronic ill-health. For more than a century, schistosomiasis has been known to be endemic in certain provinces of the Democratic Republic of Congo (DRC). However, a clear overview on the status of the disease within the country is currently lacking, which is seriously hampering control. Here, we review the available information on schistosomiasis in DRC of the past 60 years. Findings and data gaps are discussed in the perspective of upcoming control activities.An electronic literature search via PubMed complemented by manual search of non-peer-reviewed articles was conducted up to January 2015. The search concerned all relevant records related to schistosomiasis in the DRC from January 1955 onwards. A total of 155 records were found, of which 30 met the inclusion criteria. Results were summarized by geographical region, mapped, and compared with those reported sixty years ago. The available data reported schistosomiasis in some areas located in 10 of the 11 provinces of DRC. Three species of Schistosoma were found: S. mansoni, S. haematobium and S. intercalatum. The prevalence of schistosomiasis varied greatly between regions and between villages, with high values of up to 95 % observed in some communities. The overall trend over 60 years points to the spread of schistosomiasis to formerly non-endemic areas. The prevalence of schistosomiasis has increased in rural endemic areas and decreased in urban/peri-urban endemic areas of Kinshasa. Hepatosplenomegaly, urinary tract lesions and anaemia were commonly reported in schistosomiasis endemic areas but not always associated with infection status.The present review confirms that schistosomiasis is still endemic in DRC. However, available data are scattered across time and space and studies lack methodological uniformity, hampering a reliable estimation of the current status of schistosomiasis in DRC. There is a clear need for updated prevalence data

  15. Topical application of DEET for schistosomiasis

    PubMed Central

    Ramaswamy, Kalyanasundaram; He, Yi-Xun; Salafsky, Buz; Shibuya, Takeshi

    2009-01-01

    N, N-diethyl-m-toluamide (also known as DEET) is a broad-spectrum insect repellent that is used extensively against both human and animal pests, worldwide. Recent studies show that topical lipid formulations of DEET, such as LipoDEET, are highly effective in killing schistosome cercariae in the skin. Minimal systemic absorption, low manufacturing cost, and a wide range of activity against insects and schistosomes potentially makes compounds such as LipoDEET an excellent prophylactic agent against human and animal schistosomiasis in endemic areas, especially for travelers, until an effective vaccine is available. PMID:14642762

  16. Experience with schistosomiasis in Northern Ireland.

    PubMed

    Ingram, P J; Allen, D C; Irwin, S T

    1996-11-01

    Five cases of schistosomiasis have been recorded in the Belfast City Hospital Histopathology Laboratory over the last three years. The sites of infection have included the colon, bladder, uterus and seminal vesicles. All the infected individuals had visited Africa. Three of them were health care workers. The clinician must maintain a high index of suspicion when treating those with a history of travel and risk of exposure to this infection. Diagnosis is made even more critical as the condition is treatable, and serological markers can identify those with occult infection.

  17. Integration of mass drug administration programmes in Nigeria: The challenge of schistosomiasis.

    PubMed Central

    Richards, Frank O.; Eigege, Abel; Miri, Emmanuel S.; Jinadu, M. Y.; Hopkins, Donald R.

    2006-01-01

    PROBLEM: Annual mass drug administration (MDA) with safe oral anthelminthic drugs (praziquantel, ivermectin and albendazole) is the strategy for control of onchocerciasis, lymphatic filariasis (LF) and schistosomiasis. District health officers seek to integrate treatment activities in areas of overlapping disease endemicity, but they are faced with having to merge different programmatic guidelines. APPROACH: We proceeded through the three stages of integrated MDA implementation: mapping the distribution of the three diseases at district level; tailoring district training and logistics based on the results of the mapping exercises; and implementing community-based annual health education and mass treatment where appropriate. During the process we identified the "know-do" gaps in the MDA guidelines for each disease that prevented successful integration of these programmes. LOCAL SETTING: An integrated programme launched in 1999 in Plateau and Nasarawa States in central Nigeria, where all three diseases were known to occur. RELEVANT CHANGES: Current guidelines allowed onchocerciasis and LF activities to be integrated, resulting in rapid mapping throughout the two states, and states-wide provision of over 9.3 million combined ivermectin-albendazole treatments for the two diseases between 2000 and 2004. In contrast, schistosomiasis activities could not be effectively integrated because of the more restrictive guidelines, resulting in less than half of the two states being mapped, and delivery of only 701,419 praziquantel treatments for schistosomiasis since 1999. LESSONS LEARNED: Integration of schistosomiasis into other MDA programmes would be helped by amended guidelines leading to simpler mapping, more liberal use of praziquantel and the ability to administer praziquantel simultaneously with ivermectin and albendazole. PMID:16917658

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

    PubMed Central

    Chimbari, Moses J.

    2012-01-01

    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. PMID:22655171

  19. Osteopontin Is Upregulated in Human and Murine Acute Schistosomiasis Mansoni

    PubMed Central

    Pereira, Thiago Almeida; Syn, Wing-Kin; Amâncio, Frederico Figueiredo; Cunha, Pedro Henrique Diniz; Caporali, Julia Fonseca Morais; Trindade, Guilherme Vaz de Melo; Santos, Elisângela Trindade; Souza, Márcia Maria; Andrade, Zilton Araújo; Witek, Rafal P; Secor, William Evan; Pereira, Fausto Edmundo Lima; Lambertucci, José Roberto; Diehl, Anna Mae

    2016-01-01

    Background Symptomatic acute schistosomiasis mansoni is a systemic hypersensitivity reaction against the migrating schistosomula and mature eggs after a primary infection. The mechanisms involved in the pathogenesis of acute schistosomiasis are not fully elucidated. Osteopontin has been implicated in granulomatous reactions and in acute hepatic injury. Our aims were to evaluate if osteopontin plays a role in acute Schistosoma mansoni infection in both human and experimentally infected mice and if circulating OPN levels could be a novel biomarker of this infection. Methodology/Principal Findings Serum/plasma osteopontin levels were measured by ELISA in patients with acute (n = 28), hepatointestinal (n = 26), hepatosplenic (n = 39) schistosomiasis and in uninfected controls (n = 21). Liver osteopontin was assessed by immunohistochemistry in needle biopsies of 5 patients. Sera and hepatic osteopontin were quantified in the murine model of schistosomiasis mansoni during acute (7 and 8 weeks post infection, n = 10) and chronic (30 weeks post infection, n = 8) phase. Circulating osteopontin levels are increased in patients with acute schistosomiasis (p = 0.0001). The highest levels of OPN were observed during the peak of clinical symptoms (7–11 weeks post infection), returning to baseline level once the granulomas were modulated (>12 weeks post infection). The plasma levels in acute schistosomiasis were even higher than in hepatosplenic patients. The murine model mirrored the human disease. Macrophages were the major source of OPN in human and murine acute schistosomiasis, while the ductular reaction maintains OPN production in hepatosplenic disease. Soluble egg antigens from S. mansoni induced OPN expression in primary human kupffer cells. Conclusions/Significance S. mansoni egg antigens induce the production of OPN by macrophages in the necrotic-exudative granulomas characteristic of acute schistosomiasis mansoni. Circulating OPN levels are upregulated in human and

  20. Combining Remotely Sensed Environmental Characteristics with Social and Behavioral Conditions that Affect Surface Water Use in Spatiotemporal Modelling of Schistosomiasis in Ghana

    NASA Astrophysics Data System (ADS)

    Kulinkina, A. V.; Walz, Y.; Liss, A.; Kosinski, K. C.; Biritwum, N. K.; Naumova, E. N.

    2016-06-01

    Schistosoma haematobium transmission is influenced by environmental conditions that determine the suitability of the parasite and intermediate host snail habitats, as well as by socioeconomic conditions, access to water and sanitation infrastructure, and human behaviors. Remote sensing is a demonstrated valuable tool to characterize environmental conditions that support schistosomiasis transmission. Socioeconomic and behavioral conditions that propagate repeated domestic and recreational surface water contact are more difficult to quantify at large spatial scales. We present a mixed-methods approach that builds on the remotely sensed ecological variables by exploring water and sanitation related community characteristics as independent risk factors of schistosomiasis transmission.

  1. Identifying Spatial Clusters of Schistosomiasis in Anhui Province of China: A Study from the Perspective of Application.

    PubMed

    Sun, Liqian; Chen, Yue; Lynn, Henry; Wang, Qizhi; Zhang, Shiqing; Li, Rui; Xia, Congcong; Jiang, Qingwu; Hu, Yi; Gao, Fenghua; Zhang, Zhijie

    2015-09-18

    With the strategy shifting from morbidity control to transmission interruption, the burden of schistosomiasis in China has been declining over the past decade. However, further controls of the epidemic in the lake and marshland regions remain a challenge. Prevalence data at county level were obtained from the provincial surveillance system in Anhui during 1997-2010. Spatial autocorrelation analysis and spatial scan statistics were combined to assess the spatial pattern of schistosomiasis. The spatial-temporal cluster analysis based on retrospective space-time scan statistics was further used to detect risk clusters. The Global Moran's I coefficients were mostly statistically significant during 1997-2004 but not significant during 2005-2010. The clusters detected by two spatial cluster methods occurred in Nanling, Tongling, Qingyang and Wuhu during 1997-2004, and Guichi and Wuhu from 2005 to 2010, respectively. Spatial-temporal cluster analysis revealed 2 main clusters, namely Nanling (1999-2002) and Guichi (2005-2008). The clustering regions were significantly narrowed while the spatial extent became scattered during the study period. The high-risk areas shifted from the low reaches of the Yangtze River to the upper stream, suggesting the focus of schistosomiasis control should be shifted accordingly and priority should be given to the snail habitats within the high-risk areas of schistosomiasis.

  2. A Microfiltration Device for Urogenital Schistosomiasis Diagnostics.

    PubMed

    Xiao, Yuan; Lu, Yi; Hsieh, Michael; Liao, Joseph; Wong, Pak Kin

    2016-01-01

    Schistosomiasis is a parasitic disease affecting over 200 million people worldwide. This study reports the design and development of a microfiltration device for isolating schistosome eggs in urine for rapid diagnostics of urogenital schistosomiasis. The design of the device comprises a linear array of microfluidic traps to immobilize and separate schistosome eggs. Sequential loading of individual eggs is achieved autonomously by flow resistance, which facilitates observation and enumeration of samples with low-abundance targets. Computational fluid dynamics modeling and experimental characterization are performed to optimize the trapping performance. By optimizing the capture strategy, the trapping efficiency could be achieved at 100% with 300 μl/min and 83% with 3000 μl/min, and the filtration procedure could be finished within 10 min. The trapped eggs can be either recovered for downstream analysis or preserved in situ for whole-mount staining. On-chip phenotyping using confocal laser fluorescence microscopy identifies the microstructure of the trapped schistosome eggs. The device provides a novel microfluidic approach for trapping, counting and on-chip fluorescence characterization of urinal Schistosoma haematobium eggs for clinical and investigative application.

  3. The Menace of Schistosomiasis in Nigeria: Knowledge, Attitude, and Practices Regarding Schistosomiasis among Rural Communities in Kano State

    PubMed Central

    Dawaki, Salwa; Al-Mekhlafi, Hesham M.; Ithoi, Init; Ibrahim, Jamaiah; Abdulsalam, Awatif M.; Ahmed, Abdulhamid; Sady, Hany; Nasr, Nabil A.; Atroosh, Wahib M.

    2015-01-01

    Background Schistosomiasis is one of the most common neglected tropical diseases, especially in the developing countries in Africa, Asia and South America, with Nigeria having the greatest number of cases of schistosomiasis worldwide. This community-based study aims to evaluate the knowledge, attitude and practices (KAP) regarding schistosomiasis among rural Hausa communities in Kano State, Nigeria. Methods A cross-sectional study was carried out among 551 participants from Hausa communities in five local government areas in Kano State, North Central Nigeria. Demographic, socioeconomic and environmental information as well as KAP data were collected using a pre-tested questionnaire. Moreover, faecal and urine samples were collected and examined for the presence of Schistosoma mansoni and S. haematobium eggs respectively. Results The overall prevalence of schistosomiasis was 17.8%, with 8.9% and 8.3% infected with S. mansoni and S. haematobium respectively, and 0.5% had co-infection of both species. Moreover, 74.5% of the participants had prior knowledge about schistosomiasis with 67.0% of them how it is transmitted and 63.8% having no idea about the preventive measures. Three-quarters of the respondents considered schistosomiasis a serious disease while their practices to prevent infections were still inadequate, with only 34.7% of them seeking treatment from clinics/hospitals. Significant associations between the KAP and age, gender, education and employment status were reported. Multiple logistic regression analysis revealed that age, gender, history of infection and educational level of the respondents were the most important factors significantly associated with the KAP on schistosomiasis among this population. Conclusions Schistosomiasis is still prevalent among Hausa communities in Nigeria and participants’ knowledge about the disease was poor. Mass drug administration, community mobilization and health education regarding the cause, transmission and

  4. Potential schistosomiasis foci in China: a prospective study for schistosomiasis surveillance and response.

    PubMed

    Qian, Ying-Jun; Li, Shi-Zhu; Xu, Jing; Yang, Kun; Huang, Yi-Xin; Cao, Zhi-Guo; Miu, Feng; Dang, Hui; Zhang, Li-Juan; Zhang, Li; Wang, Qiang; Bergquist, Robert; Zhou, Xiao-Nong

    2015-01-01

    Schistosomiasis japonica was endemic in 12 provinces (including municipalities and autonomous regions) in the People's Republic of China (PR China). Despite the tremendous decrease of schistosomiasis incidence after almost 60 years of control, the distribution of snail-breeding sites has not been reduced significantly. In order to verify current transmission risks and identify the potential establishment of new foci of schistosomiasis driven by environmental changes, we conducted surveillance in selected risk areas of three provinces: Jiangsu, Anhui and Shandong from 2008 to 2010 in addition to routine snail surveillance. We investigated populations and possible reservoirs in sentinel sites and report that the total number of new acute cases did not diminish further in spite of ongoing control activities. In Anhui Province the local count compared to the national count was 43% (19/44) in 2008, 33% (25/75) in 2009 and 40% (17/42) in 2010. In all, 31.58 km(2) areas of snail breeding sites were newly detected nationwide through the year 2008-2010, of which the proportion of Anhui was 42% (5.03/11.98) in 2008, 95% (8.39/8.79) in 2009 and 79% (8.52/10.81) in 2010. Sentinel surveillance showed eight, nine and five confirmed cases of acute schistosomiasis in mobile populations (fishermen, migrant workers) in 2008, 2009 and 2010, respectively. All these cases were detected in Chaohu County, which must therefore be deemed an area at risk. We conclude that continuous surveillance with an emphasis on snails must be enhanced in potential risk areas in PR China.

  5. Involvement of a community in schistosomiasis control: a Kenyan experience.

    PubMed

    Katsivo, M N; Muthami, L N; Kimani, S; Karama, M; Kingori, F

    1993-08-01

    This paper illustrates how community participation was achieved in a study that was carried out between 1983-1988 whose general objective was to reduce the transmission of schistosomiasis in a rice irrigation scheme in Kenya. A community of 2,219 people was mobilized through health education, to effect changes in behaviour regarding water contact, water use and faecal disposal. Health education, alternative water sources, latrines and mass chemotherapy with praziquantel were the schistosomiasis control strategies utilized in this study. By the end of 2 years, the canals were cleared of their thick vegetation, water, sanitation, bathing and washing facilities were constructed, water contact with infective waters was reduced, faecal contamination of water was reduced, the people's knowledge on schistosomiasis increased and the rate and intensity of schistosomiasis infection was reduced. The study demonstrated that it is possible to fully involve the community in disease control efforts.

  6. Predation of schistosomiasis vector snails by ostracoda (crustacea)

    USGS Publications Warehouse

    Sohn, I.G.; Kornicker, L.S.

    1972-01-01

    An ostracod species of Cypretta is an effective predator in laboratory experiments on 1- to 3-day-old Biomphalaria glabrata, a vector snail of the blood fluke that causes the tropical and subtropical disease schistosomiasis.

  7. Long-term outcome after liver transplantation for hepatic schistosomiasis: a single-center experience over 15 years.

    PubMed

    El Moghazy, Walid; Kashkoush, Samy; O'hali, Wael; Abdallah, Khalid

    2015-01-01

    Our objective was to study the long-term outcomes of patients who had undergone liver transplantation because of schistosomiasis at our institute over the last 15 years. Four hundred forty-one patients underwent liver transplantation at our institute, and 14 did so for schistosomiasis. The survival of patients who underwent transplantation for schistosomiasis was compared with that of patients who underwent transplantation for other liver diseases. Survival curves were drawn via the Kaplan-Meier method and were compared with the log-rank test. P < 0.05 was considered significant. All 14 patients were male, and the average age was 56.8 ± 8.4 years. The average Model for End-Stage Liver Disease score was 18.2 ± 5.6, and the average Child-Pugh score was 10.6 ± 1.2. All patients had splenomegaly; pretransplant variceal bleeding occurred in 7 patients (50%), and portal vein thrombosis was diagnosed in 5 patients (36%). Patient survival was 75% 1 year after transplantation and 75% at the end of follow-up because no patients were lost after the first year. Patients who underwent transplantation for other causes achieved survival rates of 86% and 76% 1 and 10 years after transplantation, respectively. There was no significant survival difference between the 2 groups (P = 0.66). All patients who survived the early posttransplant period had functioning liver grafts with no reported diagnoses of schistosomiasis in the new grafts. In conclusion, liver transplantation for patients with schistosomiasis has a favorable outcome with no risk of reactivation.

  8. [Selection of government instruments in schistosomiasis control services].

    PubMed

    Yi, Ping; Li, Sheng-Ming; Franziska, Bieri; Yuan, Li-Ping; Zhao, Zheng-Yuan; He, Yong-Kang; Liu, Zong-Chuan; Zhou, Jie; He, Hong-Bin

    2011-06-01

    From the perspective of public administration and epidemiology, on the combination of the governance cases in the central and local government of China, the author explores ten modes of the provision of public goods and services in schistosomiasis control services, discusses seven main government instruments, and points out its pluralism, complexity and the slight changes of government' s preference. This paper also explores the approach to help the relevant government make schistosomiasis control work more practicable in field.

  9. Schistosomiasis and cancer in egypt: review.

    PubMed

    Khaled, Hussein

    2013-09-01

    Schistosomiasis is not known to be associated with any malignant disease other than bladder cancer. Bladder cancer is still the most common malignant tumor among males in Egypt and some African and Middle East countries. However, the frequency rate of bladder cancer has declined significantly during the last 25 years. This drop is mainly related to the control of Schistosomiasis. Many studies have elucidated the pathogenic events of Schistosomal-related bladder cancer with a suggested theory of pathogenesis. Furthermore, the disease presents with a distinct clinicopathologic profile that is quite different from bladder cancer elsewhere with younger age at presentation, more male predominance, more invasive stages, and occurrence of squamous cell carcinoma pathologic subtype. However, recent data suggest that this profile has been dramatically changed over the past 25 years leading to minimization of the differences between its features in Egypt and that in Western countries. Management of muscle-invasive localized disease is mainly surgery with 5-year survival rates of 30-50%. Although still a debatable issue, adjuvant and neoadjuvant chemotherapy and radiotherapy have improved treatment outcomes including survival and bladder preservation rates in most studies. This controversy emphasizes the need of individualized treatment options based on a prognostic index or other factors that can define the higher risk groups where more aggressive therapy is needed. The treatment for locally advanced and/or metastatic disease has passed through a series of clinical trials since 1970s. These phase II and III trials have included the use of single agent and combination of chemotherapy and radiotherapy regimens. The current standard of systemic chemotherapy of generally fit patients is now the gemcitabine-cisplatin combination. In conclusion, a changing pattern of bladder cancer in Egypt is clearly observed. This is mainly due to the success in the control of Schistosomiasis

  10. Urban schistosomiasis: morbidity, sociodemographic characteristics and water contact patterns predictive of infection.

    PubMed

    Firmo, J O; Lima Costa, M F; Guerra, H L; Rocha, R S

    1996-12-01

    During 1991-1992 in the Gorduras district of Belo Horizonte, the capital of Minas Gerais State in Brazil, data on 451 persons over 2 years old who carried Schistosoma mansoni eggs, as detected on at least 1 of 4 slides, were compared with data on 465 same-age persons who were free of such eggs to describe the epidemiology of schistosomiasis in this urban area. The schistosome host, Biomphalaria glabrata, was present at all 11 monitored points along streams. Snails infected with S. mansoni were found at 6 points. Sewerage was entering the streams at 2 points. 92.7% of households had a piped water supply. 89.4% had a sewerage system. 20% of the 3049 sampled peoples had schistosomiasis. The geometric mean of S. mansoni eggs stood at 70.8 eggs/gram. Only 4.7% of persons infected with S. mansoni eggs had bloody stools. Less than 3% had a hardened enlarged liver. No one had splenomegaly or splenectomy. Signs and symptoms independently associated with S. mansoni infection included bloody stools (odds ratio [OR] = 8), palpable hardened liver at the middle clavicular line (OR = 5.5), and palpable hardened liver at the middle sternal line (OR = 8). Sociodemographic variables and reasons for water contact independently associated with S. mansoni infection were age (OR = 7.1 for 10-19 years; OR = 3.3 for =or + 20 years), being male (OR = 3.1), swimming and/or playing in water (OR = 2.2 for =or- 2 times/month; OR = 3 for 2 times/month), and living in Belo Horizonte (OR = 2.5). There was no association between infection and water supply. These findings suggest a need for schistosomiasis control measures centering on water contacts for leisure in this area.

  11. Enhancing collaboration between China and African countries for schistosomiasis control.

    PubMed

    Xu, Jing; Yu, Qing; Tchuenté, Louis-Albert Tchuem; Bergquist, Robert; Sacko, Moussa; Utzinger, Jürg; Lin, Dan-Dan; Yang, Kun; Zhang, Li-Juan; Wang, Qiang; Li, Shi-Zhu; Guo, Jia-Gang; Zhou, Xiao-Nong

    2016-03-01

    Schistosomiasis remains an important public health issue, with a large number of cases reported across sub-Saharan Africa, and parts of Asia and Latin America. China was once highly endemic, but has made substantial progress and is moving towards elimination of schistosomiasis. Meanwhile, despite long-term, repeated, school-based chemotherapy in many African countries, more than 90% of all schistosomiasis cases are concentrated in Africa, and hence, this continent constitutes the key challenge for schistosomiasis control. Opportunities and issues for international collaboration in the fight against schistosomiasis are outlined with a focus on China's experiences, including the role of public health authorities and intersectoral collaboration, use of new and effective snail control approaches and diagnostic tools adapted to the specific stage of control, as well as the strengthening of risk mapping and surveillance-response mechanisms. Training courses targeting African governmental officials and professionals, coupled with field visits of African scientists and control programme managers to China, and vice versa, are considered important for improved schistosomiasis control and elimination. The crucial question remains whether the Chinese experience can be translated and applied in African countries to improve the effectiveness of health interventions and scale-up.

  12. Socioeconomic Studies of Schistosomiasis in Brazil: a Review

    PubMed Central

    Kloos, Helmut; Correa-Oliveira, Rodrigo; Quites, Humberto Ferreira; Souza, Márcia Christina; Gazzinelli, Andrea

    2009-01-01

    This review finds considerable evidence that socioeconomic status has significantly influenced the transmission, spread and treatment of schistosomiasis in Brazil. High infection rates persist among both the rural and urban poor. Rural living, poor housing and water supplies and low educational level were major factors in schistosomiasis occurrence among agricultural populations. In urban areas, prevailing living conditions in shantytowns and labor migrations from and periodic return movements to rural areas were predictive of schistosomiasis. The risk of the establishment of new transmission foci exists in both rural and urban areas, conferred by and affecting poorer people. Associations between schistosomiasis and socioeconomic parameters, persisting inequities in health services accessibility, prevailing health impacts of schistosomiasis, and the ongoing decentralization of health services point to opportunities and strategies for focused interventions aimed at promoting health-enhancing behavior and living conditions and improving access to health care. The authors call for multidisciplinary studies to better examine the complexities of the socioeconomic environment in relation to schistosomiasis and for economic programs to reduce prevailing socioeconomic inequalities. PMID:18694715

  13. PARASITES AND POVERTY: THE CASE OF SCHISTOSOMIASIS

    PubMed Central

    King, Charles H.

    2009-01-01

    Simultaneous and sequential transmission of multiple parasites, and their resultant overlapping chronic infections, are facts of life in many underdeveloped rural areas. These represent significant but often poorly-measured health and economic burdens for affected populations. For example, the chronic inflammatory process associated with long-term schistosomiasis contributes to anaemia and undernutrition, which, in turn, can lead to growth stunting, poor school performance, poor work productivity, and continued poverty. To date, most national and international programs aimed at parasite control have not considered the varied economic and ecological factors underlying multi-parasite transmission, but some are beginning to provide a coordinated approach to control. In addition, interest is emerging in new studies for the re-evaluation and recalibration of the health burden of helminthic parasite infection. Their results should highlight the strong potential of integrated parasite control in efforts for poverty reduction. PMID:19962954

  14. [Laboratory animal infection in modeling intestinal schistosomiasis].

    PubMed

    Zelia, O P

    1984-01-01

    A comparative efficiency of different regimes for infecting laboratory animals has been determined in order to find out optimal conditions under which an experimental model of intestinal schistosomiasis (infection with Schistosoma mansoni) can be maintained. When evaluating the results of laboratory definitive hosts infection we took into account the character of Schistosoma distribution in animals, which with high probability rate was modelled by means of negative binomial distribution. The main parameters of this distribution were used for determination of effective doses and methods of animals infection alongside with generally accepted indices of infection rate and intensiveness. Analysis of the data obtained has shown that the infection of 150 cercarians per mouse and 200 cercarians per golden and striped hairy-footed hamster by their subcutaneous administration creates optimal density of parasites in the host. Results of investigations have shown that striped hairy-footed hamsters can be used as definitive hosts of Schistosoma.

  15. [Appropriate technology: a driver to eliminate schistosomiasis in China. In- sights gained from the First Forum on Schistosomiasis Control in China].

    PubMed

    Hong, Qing-biao; Wen, Li-yong; Zhong, Bo; Yang, Hai-tao; Li, Shi-zhu; Liang, You-sheng; Zhang, Shi-qing; Ren, Guang-hui; Lin, Dan-dan; Sun, Le-ping; Zhou, Xiao-nong

    2015-10-01

    This paper described the First Forum on Schistosomiasis Control in China. With "Appropriate technology is essential to schistosomiasis prevention and control" as the topic, the forum shared the main interventions and experiences for schistosomiasis control and elimination, exhibited the recent achievements gained from the development of appropriate technology for schistosomiasis control, showed the technical support of appropriate technology for schistosomiasis elimination, and proposed the priority for the future research and development of appropriate technology for schistosomiasis control and elimination in China. It is considered that the forum builds a bridge for communicating information between the administrative sectors and specialized prevention and control institutions, between research institutions and manufactures, and between experts/professors and grassroots professional staff, and provides a platform to communicate the national schistosomiasis control knowledge of China.

  16. Schistosomiasis in Lake Malaŵi villages.

    PubMed

    Madsen, Henry; Bloch, Paul; Makaula, Peter; Phiri, Happy; Furu, Peter; Stauffer, Jay R

    2011-06-01

    Historically, open shorelines of Lake Malaŵi were free from schistosome, Schistosoma haematobium, transmission, but this changed in the mid-1980s, possibly as a result of over-fishing reducing density of molluscivore fishes. Very little information is available on schistosome infections among people in lake-shore communities and therefore we decided to summarise data collected from 1998 to 2007. Detailed knowledge of the transmission patterns is essential to design a holistic approach to schistosomiasis control involving the public health, fisheries and tourism sectors. On Nankumba Peninsula, in the southern part of the lake, inhabitants of villages located along the shores of Lake Malaŵi have higher prevalence of S. haematobium infection than those living in inland villages. Overall prevalence (all age classes combined) of urinary schistosomiasis in 1998/1999 ranged from 10.2% to 26.4% in inland villages and from 21.0% to 72.7% in lakeshore villages; for school children prevalence of infection ranged from 15.3% to 57.1% in inland schools and from 56.2% to 94.0% in lakeshore schools. Inhabitants on the islands, Chizumulu and Likoma, also have lower prevalence of infection than those living in lakeshore villages on Nankumba Peninsula. This increased prevalence in lakeshore villages is not necessarily linked to transmission taking place in the lake itself, but could also be due to the presence of more numerous typical inland transmission sites (e.g., streams, ponds) being close to the lake. Temporal data witness of intense transmission in some lakeshore villages with 30-40% of children cleared from infection becoming reinfected 12 months later (also lakeshore village). The level of S. mansoni infection is low in the lakeshore communities. Findings are discussed in relation to fishing in the lake.

  17. Spatially Explicit Modeling of Schistosomiasis Risk in Eastern China Based on a Synthesis of Epidemiological, Environmental and Intermediate Host Genetic Data

    PubMed Central

    Schrader, Matthias; Hauffe, Torsten; Zhang, Zhijie; Davis, George M.; Jopp, Fred; Remais, Justin V.; Wilke, Thomas

    2013-01-01

    Schistosomiasis japonica is a major parasitic disease threatening millions of people in China. Though overall prevalence was greatly reduced during the second half of the past century, continued persistence in some areas and cases of re-emergence in others remain major concerns. As many regions in China are approaching disease elimination, obtaining quantitative data on Schistosoma japonicum parasites is increasingly difficult. This study examines the distribution of schistosomiasis in eastern China, taking advantage of the fact that the single intermediate host serves as a major transmission bottleneck. Epidemiological, population-genetic and high-resolution ecological data are combined to construct a predictive model capable of estimating the probability that schistosomiasis occurs in a target area (“spatially explicit schistosomiasis risk”). Results show that intermediate host genetic parameters are correlated with the distribution of endemic disease areas, and that five explanatory variables—altitude, minimum temperature, annual precipitation, genetic distance, and haplotype diversity—discriminate between endemic and non-endemic zones. Model predictions are correlated with human infection rates observed at the county level. Visualization of the model indicates that the highest risks of disease occur in the Dongting and Poyang lake regions, as expected, as well as in some floodplain areas of the Yangtze River. High risk areas are interconnected, suggesting the complex hydrological interplay of Dongting and Poyang lakes with the Yangtze River may be important for maintaining schistosomiasis in eastern China. Results demonstrate the value of genetic parameters for risk modeling, and particularly for reducing model prediction error. The findings have important consequences both for understanding the determinants of the current distribution of S. japonicum infections, and for designing future schistosomiasis surveillance and control strategies. The results

  18. [African schistosomiasis at the invasion stage. Criteria for diagnosis. Control after 5 years (author's transl)].

    PubMed

    Laverdant, C; Thabaut, A; Hardelin, J; Cristau, P; Molinie, C; Durosoir, J L; Essioux, H; Daly, J P; Larroque, P; Cathalan, G

    1980-01-01

    The authors expose their conclusions after controlling 181 young soldiers affected by schistosomiasis in an epidemic having occured in Tchad en 1973-74, none of them having been later on submitted to parasitic infection: --relative value of classical diagnosis criteria (50 p. 100); --reliability of immunologic symptoms; -- frequency, importance and precocity of specific granulomatous hepatic changes, detected by laparoscopie and biopsy (87,2 p. 100 of the cases). The value of niridazole is confirmed but continuance of granulomatosis after clinical recovery is not an exceptionnal possibility five years after the treatment, then raising diagnostic and immunologic problems.

  19. [Application of high resolution remote sensing technology in research of schistosomiasis surveillance].

    PubMed

    Xue, Jing-bo; Zhang, Li-juan; Wang, Qiang; Lu, Yan-xin; Li, Shi-zhu

    2015-10-01

    Schistosomiasis is closely related to environmental factors, the changes of environmental factors, such as vegetation, temperature, hydrology and soil, could impact the transmission of the disease. The environmental factors associated with schistosomiasis could be extracted by remote sensing technology quickly and precisely, and be applied to monitor the schistosomiasis transmission. The studies on high resolution remote sensing technology applied in the research of schistosomiasis are reviewed in this paper.

  20. Spatiotemporal Patterns of Schistosomiasis-Related Deaths, Brazil, 2000-2011.

    PubMed

    Martins-Melo, Francisco Rogerlândio; Pinheiro, Marta Cristhiany Cunha; Ramos, Alberto Novaes; Alencar, Carlos Henrique; Bezerra, Fernando Schemelzer de Moraes; Heukelbach, Jorg

    2015-10-01

    We analyzed spatiotemporal patterns of 8,756 schistosomiasis-related deaths in Brazil during 2000-2011 and identified high-risk clusters of deaths, mainly in highly schistosomiasis-endemic areas along the coast of Brazil's Northeast Region. Schistosomiasis remains a neglected public health problem with a high number of deaths in disease-endemic and emerging focal areas.

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

    PubMed Central

    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

  2. Design of schistosomiasis ontology (IDOSCHISTO) extending the infectious disease ontology.

    PubMed

    Camara, Gaoussou; Despres, Sylvie; Djedidi, Rim; Lo, Moussa

    2013-01-01

    Epidemiological monitoring of the schistosomiasis' spreading brings together many practitioners working at different levels of granularity (biology, host individual, host population), who have different perspectives (biology, clinic and epidemiology) on the same phenomenon. Biological perspective deals with pathogens (e.g. life cycle) or physiopathology while clinical perspective deals with hosts (e.g. healthy or infected host, diagnosis, treatment, etc.). In an epidemiological perspective corresponding to the host population level of granularity, the schistosomiasis disease is characterized according to the way (causes, risk factors, etc.) it spreads in this population over space and time. In this paper we provide an ontological analysis and design for the Schistosomiasis domain knowledge and spreading dynamics. IDOSCHISTO - the schistosomiasis ontology - is designed as an extension of the Infectious Disease Ontology (IDO). This ontology aims at supporting the schistosomiasis monitoring process during a spreading crisis by enabling data integration, semantic interoperability, for collaborative work on one hand and for risk analysis and decision making on the other hand.

  3. Application of praziquantel in schistosomiasis japonica control strategies in China.

    PubMed

    Wu, Wei; Huang, Yixin

    2013-03-01

    Schistosomiasis remains a major public health problem with an estimated 200 million people infected in the world, and in China, schistosomiasis japonica is endemic in the south part of the country. In 1960s, before praziquantel was developed, there were about seven million patients. Praziquantel has a high efficacy against Schistosoma, few and transient side effects, simple administration and competitive cost, and is equally suited for both individual and large-scale treatment. Praziquantel has been widely used in the morbidity control, transmission control, and prevention of schistosomiasis japonica in China since 1980s. The schemes of praziquantel chemotherapy include the diagnostic selective chemotherapy, extensive chemotherapy, mass chemotherapy, stratified chemotherapy, phased chemotherapy, etc. Chemotherapy alone or combined with other control measure, such as Oncomelania snail control, health education, safety water supply, and so on, has achieved a great success, and there are only 0.33 million infected people now. This paper reviews the application of praziquantel in the schistosomiasis japonica control strategies in China so as to provide the rich experiences for reference of health workers of other countries where schistosomiasis is endemic.

  4. Evaluation of Eight Serological Tests for Diagnosis of Imported Schistosomiasis

    PubMed Central

    Dittrich, Sabine; Bäumer, Britta

    2012-01-01

    The diagnosis of schistosomiasis in individuals from countries where the disease is not endemic is challenging, and few data are available on the accuracy of serological diagnosis in those patients. We evaluated the performance of eight serological assays, including four commercial kits, in the diagnosis of imported schistosomiasis in individuals from areas where the disease is not endemic, including six enzyme-linked immunosorbent assays using three different antigens, an indirect hemagglutination assay, and an indirect immunofluorescent-antibody test. To analyze the assays, we used a total of 141 serum samples, with 121 derived from patients with various parasitic infections (among which were 37 cases of schistosomiasis) and 20 taken from healthy volunteers. The sensitivity values for detection of schistosomiasis cases ranged from 41% to 78% and were higher for Schistosoma mansoni than for S. haematobium infections. Specificity values ranged from 76% to 100%; false-positive results were most frequent for samples from patients with cestode infections. By combining two or more tests, sensitivity improved markedly and specificity decreased only moderately. Serological tests are useful instruments for diagnosing imported schistosomiasis in countries where the disease is not endemic, but due to limitations in test sensitivities, we recommend the use of two or more assays in parallel. PMID:22441394

  5. Urinary schistosomiasis and malaria associated anemia in Ethiopia

    PubMed Central

    Deribew, Ketema; Tekeste, Zinaye; Petros, Beyene

    2013-01-01

    Objective To assess the prevalence of anemia in children with urinary schistosomiasis, malaria and concurrent infections by the two diseases. Methods Urine and blood samples were collected from 387 children (216 males and 171 females) to examine urinary schistosomiasis and malaria and to determine hemoglobin concentration at Hassoba and Hassoba Buri village in Amibara woreda, Afar region, Ethiopia. Results The overall prevalence of urinary schistosomiasis and Plasmodium falciparum malaria was 24.54% and 6.20% respectively. Only 2.84% of children carried concurrent infections of both parasites. There was high percentage of anemic patients (81.81%) in the coinfected cases than in either malaria (33.3%) or schistosomiasis (38.94%) cases. There was significantly low mean hemoglobin concentration in concurrently infected children than non-infected and single infected (P<0.05). The mean hemoglobin concentration between Plasmodium falciparum and S. haematobium infected children showed no significant difference (P>0.05). The level of hemoglobin was negatively correlated with the number of S. haematobium eggs/10 mL urine (r=-0.6) and malaria parasitemia (r=-0.53). Conclusions The study showed that anemia is higher in concurrently infected children than non-infected and single infected. Furthermore, level of hemoglobin was negatively correlated with the number of S. haematobium eggs and malaria parsitemia. Therefore, examination of hemoglobin status in patients co-infected with malaria and schistosomiasis is important to reduce the risk of anemia and to improve health of the community. PMID:23620856

  6. Assessment of schistosomiasis in the Dominican Republic.

    PubMed Central

    Schneider, C R; Hiatt, R A; Malek, E A; Ruiz-Tiben, E

    1985-01-01

    Active transmission of intestinal schistosomiasis is currently limited to the southeastern part of the Dominican Republic. A population-based stool survey in 1980 detected 4 asymptomatic individuals among 114 selected at random in 2 towns and a rural community in El Seibo Province. The distribution of the transmitting snail, Biomphalaria glabrata, considerably exceeds that of Schistosoma mansoni, extending to the National District and capital city of Santo Domingo and well into certain central valley provinces. There is evidence that transmission sites have shifted during the past three decades because of urban development, molluscicidal activities and, perhaps, introduction of competing mollusks. In spite of intermittent control activities, the combination of domestic and recreational use of streams with consequent fecal contamination, and the extended distribution of B. glabrata indicates that the potential for new transmission foci is as great today as it was 10 years ago. This potential transmission of S. mansoni is a continuing threat to public health in the Dominican Republic. PMID:3931167

  7. Evaluation of Lethal Giant Larvae as a Schistosomiasis Vaccine Candidate

    PubMed Central

    Cao, Yufan; Qiao, Hongbin; Shi, Yanli; Han, Yu; Liu, Jinming; Li, Hao; Lu, Ke; Lin, Jiaojiao

    2016-01-01

    Schistosomiasis is a neglected tropical disease of humans, and it is considered to be the second most devastating parasitic disease after malaria. Eggs produced by normally developed female worms are important in the transmission of the parasite, and they responsible for the pathogenesis of schistosomiasis. The tumor suppressor gene lethal giant larvae (lgl) has an essential function in establishing apical-basal cell polarity, cell proliferation, differentiation, and tissue organization. In our earlier study, downregulation of the lgl gene induced a significant reduction in the egg hatching rate of Schistosoma japonicum (Sj) eggs. In this study, the Sjlgl gene was used as a vaccine candidate against schistosomiasis, and vaccination achieved and maintained a stable reduction of the egg hatching rate, which is consistent with previous studies, in addition to reducing the worm burden and liver egg burden in some trials. PMID:27957496

  8. Popular Beliefs about the Infectivity of Water among School Children in Two Hyperendemic Schistosomiasis Areas of Brazil

    PubMed Central

    Gazzinelli, Maria Flávia Carvalho; Kloos, Helmut; de Cássia Marques, Rita; dos Reis, Dener Carlos; Gazzinelli, Andrea

    2009-01-01

    This article examines changing common knowledge of elementary school children to scientific knowledge related to the relationship between water characteristics and the transmission of schistosomiasis through health education. A review of the literature and two case studies from rural elementary schools in Brazil show how the prevailing concept of dirty and polluted water, which has operated as an epistemological obstacle for acquiring scientific knowledge, may be related to symbolic thought and cultural parameters. Through an educational intervention not commonly applied to health programs involving elementary school students in two schistosomiasis-endemic rural communities in Brazil this paper describes the difficulties researchers encountered in changing the prevailing perception that very dirty and polluted water provides optimal conditions for schistosome transmission, to the scientifically accepted view that transmission occurs most often in visually clean, although fecally contaminated water. This conceptual difficulty may be largely explained in terms of the symbolism involved in clean and dirty water and the life-giving quality of water. Based on our results, we recommend that knowledge about water-related beliefs and concepts among school children should be considered in school-based health education programs in areas of endemic schistosomiasis and possibly other intestinal infections. PMID:18599008

  9. Five-Year Longitudinal Assessment of the Downstream Impact on Schistosomiasis Transmission following Closure of the Three Gorges Dam

    PubMed Central

    Gray, Darren J.; Thrift, Aaron P.; Williams, Gail M.; Zheng, Feng; Li, Yue-Sheng; Guo, Jiagang; Chen, Honggen; Wang, Tianping; Xu, Xin Jiang; Zhu, Rong; Zhu, Hongqing; Cao, Chun Li; Lin, Dan Dan; Zhao, Zhen Yuan; Li, Robert S.; Davis, George M.; McManus, Donald P.

    2012-01-01

    Background Schistosoma japonicum is a major public health concern in the Peoples' Republic of China (PRC), with about 800,000 people infected and another 50 million living in areas at risk of infection. Based on ecological, environmental, population genetic and molecular factors, schistosomiasis transmission in PRC can be categorised into four discrete ecosystems or transmission modes. It is predicted that, long-term, the Three Gorges Dam (TGD) will impact upon the transmission of schistosomiasis in the PRC, with varying degree across the four transmission modes. Methodology/Principal Findings We undertook longitudinal surveillance from 2002 to 2006 in sentinel villages of the three transmission modes below the TGD across four provinces (Hunan, Jiangxi, Hubei and Anhui) to determine whether there was any immediate impact of the TGD on schistosomiasis transmission. Eight sentinel villages were selected to represent both province and transmission mode. The primary end point measured was human incidence. Here we present the results of this five-year longitudinal cohort study. Results showed that the incidence of human S. japonicum infection declined considerably within individual villages and overall mode over the course of the study. This is also reflected in the yearly odds ratios (adjusted) for infection risk that showed significant (P<0.01) downward trends in all modes over the follow-up period. Conclusions/Significance The decrease in human S. japonicum incidence observed across all transmission modes in this study can probably be attributed to the annual human and bovine PZQ chemotherapy. If an increase in schistosome transmission had occurred as a result of the TGD, it would be of negligible size compared to the treatment induced decline seen here. It appears therefore that there has been virtually no immediate impact of the TGD on schistosomiasis transmission downstream of the dam. PMID:22506083

  10. The Nephropathy of Experimental Hepatosplenic Schistosomiasis

    PubMed Central

    Cavallo, Tito; Galvanek, Eleonora G.; Ward, Peter A.; von Lichtenberg, Franz

    1974-01-01

    The glomerular lesions induced in 10 chimpanzees infected with variable numbers of Schistosoma japonicum cercariae were studied by means of light and electron microscopy and fluorescent antibody technic. Ten animals served as controls; 5 were uninfected and 5 were only lightly infected. The animals were observed for periods ranging from 3 to 17 months, and by the time of sacrifice, all had developed advanced liver fibrosis. In general, the degree of glomerular injury was related to infection intensity and degree and duration of portal liver fibrosis. Some animals had terminal BUN elevation and slight proteinuria. By light and electron microscopy, in the initial stages, only part of the glomeruli were involved and exhibited mesangial matrix expansion and mesangial cell proliferation with intracellular hyaline droplets. At later stages, a larger number of glomeruli were affected and exhibited diffuse hypercellularity, glomerular basement thickening, mesangial sclerosis and less often, focal necrosis, crescent formation, synechiae and global hyalinization. In addition, there were discrete electron-dense deposits localized in the mesangial area in some glomeruli. Immunofluorescent studies utilizing antisera to chimpanzee γ-globulin and complement (C3) and to human properdin disclosed only faint deposits of C3, apparently in mesangial areas. The association of hepatosplenic schistosomiasis and nephropathy, the possible role of schistosomal antigen and the mechanism(s) of such glomerular injuries are reviewed and compared with the disease in humans and other host species infected with Schistosoma. ImagesFig 1Fig 2Fig 3Fig 4Figs 5-8Fig 9Fig 10 PMID:4137991

  11. Changing Patterns of Spatial Clustering of Schistosomiasis in Southwest China between 1999–2001 and 2007–2008: Assessing Progress toward Eradication after the World Bank Loan Project

    PubMed Central

    Hu, Yi; Xiong, Chenglong; Zhang, Zhijie; Luo, Can; Cohen, Ted; Gao, Jie; Zhang, Lijuan; Jiang, Qingwu

    2014-01-01

    We compared changes in the spatial clustering of schistosomiasis in Southwest China at the conclusion of and six years following the end of the World Bank Loan Project (WBLP), the control strategy of which was focused on the large-scale use of chemotherapy. Parasitological data were obtained through standardized surveys conducted in 1999–2001 and again in 2007–2008. Two alternate spatial cluster methods were used to identify spatial clusters of cases: Anselin’s Local Moran’s I test and Kulldorff’s spatial scan statistic. Substantial reductions in the burden of schistosomiasis were found after the end of the WBLP, but the spatial extent of schistosomiasis was not reduced across the study area. Spatial clusters continued to occur in three regions: Chengdu Plain, Yangtze River Valley, and Lancang River Valley during the two periods, and regularly involved five counties. These findings suggest that despite impressive reductions in burden, the hilly and mountainous regions of Southwest China remain at risk of schistosome re-emergence. Our results help to highlight specific locations where integrated control programs can focus to speed the elimination of schistosomiasis in China. PMID:24394217

  12. Urban schistosomiasis and soil transmitted helminthiases in young school children in Dar es Salaam and Tanga, Tanzania, after a decade of anthelminthic intervention.

    PubMed

    Mwakitalu, Mbutolwe E; Malecela, Mwele N; Mosha, Franklin W; Simonsen, Paul E

    2014-05-01

    Rapid urbanization in resource poor countries often results in expansion of unplanned settlements with overcrowding and inadequate sanitation. These conditions potentially support transmission of schistosomiasis and soil transmitted helminths (STH), but knowledge on the occurrence, transmission and control of these infections in urban settings is limited. The present study assessed the status of urinary schistosomiasis and STH across two different-sized cities in Tanzania - Dar es Salaam and Tanga - after a decade of anthelminthic intervention. Primary school children were examined for parasite eggs in urine and stool. Questionnaires were administered to the children, and observations were made on the urban environments. The burden of urinary schistosomiasis and STH was found to be low in both cities (overall 1.2% in Dar es Salaam and 0.3% in Tanga for urinary schistosomiasis; overall <1% in Dar es Salaam and 1-2% in Tanga for each STH infection), and the identified cases showed no clear pattern of spatial distribution. The findings indicated that a marked decrease in prevalence of these infections had occurred in the two cities during recent years. The observed promising developments appeared to have been accomplished by implementation of drug based intervention programs, in combination with environmental change (fewer snail habitats) and generally improved levels of hygiene. Continued efforts, including anthelminthic treatment and health education, are important to maintain these positive achievements.

  13. Changing patterns of spatial clustering of schistosomiasis in Southwest China between 1999-2001 and 2007-2008: assessing progress toward eradication after the World Bank Loan Project.

    PubMed

    Hu, Yi; Xiong, Chenglong; Zhang, Zhijie; Luo, Can; Cohen, Ted; Gao, Jie; Zhang, Lijuan; Jiang, Qingwu

    2014-01-03

    We compared changes in the spatial clustering of schistosomiasis in Southwest China at the conclusion of and six years following the end of the World Bank Loan Project (WBLP), the control strategy of which was focused on the large-scale use of chemotherapy. Parasitological data were obtained through standardized surveys conducted in 1999-2001 and again in 2007-2008. Two alternate spatial cluster methods were used to identify spatial clusters of cases: Anselin's Local Moran's I test and Kulldorff's spatial scan statistic. Substantial reductions in the burden of schistosomiasis were found after the end of the WBLP, but the spatial extent of schistosomiasis was not reduced across the study area. Spatial clusters continued to occur in three regions: Chengdu Plain, Yangtze River Valley, and Lancang River Valley during the two periods, and regularly involved five counties. These findings suggest that despite impressive reductions in burden, the hilly and mountainous regions of Southwest China remain at risk of schistosome re-emergence. Our results help to highlight specific locations where integrated control programs can focus to speed the elimination of schistosomiasis in China.

  14. [An outbreak of acute schistosomiasis at Porto de Galinhas beach, Pernambuco, Brazil].

    PubMed

    Barbosa, C S; Domingues, A L; Abath, F; Montenegro, S M; Guida, U; Carneiro, J; Tabosa, B; Moraes, C N; Spinelli, V

    2001-01-01

    We recently confirmed several cases of acute schistosomiasis in Porto de Galinhas beach, Northeast Brazil. A total of 662 patients were diagnosed by parasitological and clinical examinations. The infection likely occurred during the September 7 national holiday, when heavy rainfall flooded the Ipojuca River and people were infected when the water covered their yards. Families were continuously exposed to infection for a period of three weeks until the water had completely dried up. Previous investigation suggests that snail vectors were introduced as a result of landfill in marshy areas. The swamp-flooding of such areas facilitated the emergence of slums surrounded by snail breeding sites. Heavy rainfall caused open-air sewage ditches to overflow, allowing for infection of snails by Schistosoma mansoni. Thus, continuous floods were responsible for the spread of human infection. Clinical and laboratory results identified 62% of acute cases of S. mansoni. Complementary studies are being conducted to define the impact and epidemiological meaning of the acute schistosomiasis outbreak.

  15. Multivalent anthelminthic vaccine to prevent hookworm and schistosomiasis.

    PubMed

    Hotez, Peter J; Bethony, Jeffrey M; Oliveira, Sergio Costa; Brindley, Paul J; Loukas, Alex

    2008-08-01

    Hookworm infection and schistosomiasis are two of the world's most important human parasitic infections, affecting hundreds of millions of people in developing countries. Measured together in disability-adjusted life years, hookworm infection and schistosomiasis rank closely behind malaria as the most prevalent human parasitic diseases. A major approach for the control of these two helminth infections relies on periodic, mass chemotherapy with anthelminthics. However, high rates of post-treatment reinfection, the declining efficacy with repeated treatment, rebound morbidity (in the case of schistosomiasis) and the potential for the emergence of anthelminthic drug resistance threaten the sustainability of mass drug administration as the only form of control. Hence, there is a strong rationale for developing a vaccine that simultaneously targets both hookworms and schistosomes because of similarities in the pathobiology of both parasites, the ability of both helminths to cause anemia and their coendemicity in sub-Saharan Africa, Brazil and East Asia. A multivalent anthelminthic vaccine for hookworm infection and schistosomiasis would represent an important new tool for combating disease and poverty.

  16. Local and International Implications of Schistosomiasis Acquired in Corsica, France.

    PubMed

    Gautret, Philippe; Mockenhaupt, Frank P; von Sonnenburg, Frank; Rothe, Camilla; Libman, Michael; Van De Winkel, Kristina; Bottieau, Emmanuel; Grobusch, Martin P; Hamer, Davidson H; Esposito, Douglas H; Parola, Philippe; Schlagenhauf, Patricia

    2015-10-01

    We report 11 cases of schistosomiasis in international travelers who had bathed in rivers in Corsica, France, during 2012-2014. The infections were diagnosed in 2014 and reported to the GeoSentinel Surveillance Network and European Travel Medicine Network. Travelers can be sentinels for emerging infections; thus, this situation warrants a concerted human and veterinary epidemiologic response.

  17. Africa: Schistosomiasis in Africa and the Role of Environmental Education.

    ERIC Educational Resources Information Center

    Stapp, William B.

    1985-01-01

    Illustrates problems involved in controlling a public health disease (schistosomiasis) which is interwoven into a country's religious, economic, political, educational, and social systems. The strong relationship between the disease and development of irrigation systems is pointed out. A successful education and integrative program is described.…

  18. Schistosomiasis and the pulmonary vasculature (2013 Grover Conference series)

    PubMed Central

    2014-01-01

    Abstract Inflammation is associated with multiple forms of pulmonary arterial hypertension (PAH), including autoimmune (scleroderma) and infectious (HIV, schistosomiasis) etiologies. More than 200 million people worldwide are infected with Schistosoma, predominantly in Brazil, Africa, the Middle East, and South Asia. Schistosomiasis causes PAH in about 6.1% of those chronically infected and is particularly associated with the species Schistosoma mansoni. Treatment for schistosomiasis-associated PAH includes antihelminthic treatment, if active infection is present (although associated with little immediate benefit to the pulmonary hypertension), and then pharmacologic treatment with targeted pulmonary vascular therapies, including phosphodiesterase type 5 inhibitors and endothelin receptor antagonists. The pathophysiological mechanism by which this parasitic infection causes pulmonary hypertension is unknown but is unlikely to be simple mechanical obstruction of the pulmonary vasculature by parasite eggs. Preexisting hepatosplenic disease due to Schistosoma infection is likely important because of portopulmonary hypertension and/or because it allows egg embolization to the lung by portocaval shunts. Potential immune signaling originating in the periegg granulomas causing the pulmonary vascular disease includes the cytokines interleukin (IL)-4, IL-6, IL-13, and transforming growth factor β. Modulating these pathways may be possible targets for future therapy of schistosomiasis-associated PAH specifically, and study of this disease may provide novel insights into other inflammatory causes of PAH. PMID:25621148

  19. Impact of human schistosomiasis in sub-Saharan Africa.

    PubMed

    Adenowo, Abiola Fatimah; Oyinloye, Babatunji Emmanuel; Ogunyinka, Bolajoko Idiat; Kappo, Abidemi Paul

    2015-01-01

    Schistosomiasis, a neglected tropical disease of poverty ranks second among the most widespread parasitic disease in various nations in sub-Saharan Africa. Neglected tropical diseases are causes of about 534,000 deaths annually in sub-Saharan Africa and an estimated 57 million disability-adjusted life-years are lost annually due to the neglected tropical diseases. The neglected tropical diseases exert great health, social and financial burden on economies of households and governments. Schistosomiasis has profound negative effects on child development, outcome of pregnancy, and agricultural productivity, thus a key reason why the "bottom 500 million" inhabitants of sub-Saharan Africa continue to live in poverty. In 2008, 17.5 million people were treated globally for schistosomiasis, 11.7 million of those treated were from sub-Saharan Africa. This enervating disease has been successfully eradicated in Japan, as well as in Tunisia. Morocco and some Caribbean Island countries have made significant progress on control and management of this disease. Brazil, China and Egypt are taking steps towards elimination of the disease, while most sub-Saharan countries are still groaning under the burden of the disease. Various factors are responsible for the continuous and persistent transmission of schistosomiasis in sub-Saharan Africa. These include climatic changes and global warming, proximity to water bodies, irrigation and dam construction as well as socio-economic factors such as occupational activities and poverty. The morbidity and mortality caused by this disease cannot be overemphasized. This review is an exposition of human schistosomiasis as it affects the inhabitants of various communities in sub-Sahara African countries. It is hoped this will bring a re-awakening towards efforts to combat this impoverishing disease in terms of vaccines development, alternative drug design, as well as new point-of-care diagnostics.

  20. Screening of Tanzanian women of childbearing age for urinary schistosomiasis: validity of urine reagent strip readings and self-reported symptoms.

    PubMed Central

    Poggensee, G.; Krantz, I.; Kiwelu, I.; Feldmeier, H.

    2000-01-01

    The screening of women of childbearing age for haematuria, leukocyturia and proteinuria to detect urinary schistosomiasis can be confounded by several factors such as menstruation, pregnancy and genitourinary infections. We therefore undertook a study in an area endemic for Schistosoma haematobium in the United Republic of Tanzania to carry out the following: assess the sensitivity, specificity and predictive values--in women of childbearing age--of indirect indicators of urinary schistosomiasis, as measured by urine reagent strip readings; assess the predictive values of self-reported symptoms; and finally to estimate the morbidity attributable to S. haematobium. A total of 303 women (128 and 175, respectively, living in high- and low-risk sites) participated in the study. Haematuria was more frequent among women excreting S. haematobium eggs than among those who did not (65% versus 32%). The predictive potential of all indirect disease markers was poor in the highly endemic site, while in the sites with low endemicity the negative predictive values were high. Among infected women, 54% of haematuria could be attributed to S. haematobium, but for patients with more than 10 eggs/10 ml the attributable fraction rose to 70%. Symptoms of "bloody urine" and "pain while urinating" were recalled significantly more often by women living in the highly endemic site. On a population level, one-third of the self-reported cases with bloody urine could be attributed to urinary schistosomiasis. Screening of women of childbearing age for urinary schistosomiasis using urine reagent strips can be biased in two directions. The prevalence of S. haematobium will be overestimated if other causes of haematuria, such as reproductive tract infections, are highly endemic. On the other hand, women with light or very light infections will be missed and will not be treated. This is of concern because genital schistosomiasis, a possible risk factor for the transmission of HIV, occurs among

  1. [Epidemic characteristics and security implications of Africa schistosomiasis on people who go to Africa].

    PubMed

    Pan, Xiang; Zhou, Yi-biao; Yang, Ya; Song, Xiu-xia; Jiang, Qing-wu

    2015-08-01

    With the economic globalization, and the economic and trade cooperation and cultural communication between China and African countries, more and more Chinese people go to Africa for work or travel. However, there is a quick increase of imported schistosomiasis patients who return from Africa. This paper analyzes the security implications of epidemic characteristics of Africa schistosomiasis on the people who go to Africa, and put forward several suggestions to help them to prevent from schistosomiasis.

  2. [Acute schistosomiasis: lessons learned from a cohort of 42 exposed travelers].

    PubMed

    Rochat, L; Bizzini, A; Bochud, P-Y; Senn, N; De Vallière, S; Genton, B

    2015-05-06

    Acute schistosomiasis is a regularly encountered disease in travelers. Because of the temporal delay, its unspecific presentation and the spontaneous resolution, acute schistosomiasis can easily remain unrecognized by physicians who are not familiar with tropical pathologies. In December 2011, a female traveler was admitted to the hospital with undetermined fever after having returned from Madagascar where she bathed in fresh water. Acute schistosomiasis was diagnosed and infection was suspected among other travelers of her group. Seroconversion was confirmed among 78% of participants. This article intends to clarify the preventive and diagnostic strategies based on the lessons learned from this cluster of 42 travelers exposed to schistosomiasis.

  3. Circulating antigen tests and urine reagent strips for diagnosis of active schistosomiasis in endemic areas

    PubMed Central

    Ochodo, Eleanor A; Gopalakrishna, Gowri; Spek, Bea; Reitsma, Johannes B; van Lieshout, Lisette; Polman, Katja; Lamberton, Poppy; Bossuyt, Patrick Mm; Leeflang, Mariska Mg

    2015-01-01

    Background Point-of-care (POC) tests for diagnosing schistosomiasis include tests based on circulating antigen detection and urine reagent strip tests. If they had sufficient diagnostic accuracy they could replace conventional microscopy as they provide a quicker answer and are easier to use. Objectives To summarise the diagnostic accuracy of: a) urine reagent strip tests in detecting active Schistosoma haematobium infection, with microscopy as the reference standard; and b) circulating antigen tests for detecting active Schistosoma infection in geographical regions endemic for Schistosoma mansoni or S. haematobium or both, with microscopy as the reference standard. Search methods We searched the electronic databases MEDLINE, EMBASE, BIOSIS, MEDION, and Health Technology Assessment (HTA) without language restriction up to 30 June 2014. Selection criteria We included studies that used microscopy as the reference standard: for S. haematobium, microscopy of urine prepared by filtration, centrifugation, or sedimentation methods; and for S. mansoni, microscopy of stool by Kato-Katz thick smear. We included studies on participants residing in endemic areas only. Data collection and analysis Two review authors independently extracted data, assessed quality of the data using QUADAS-2, and performed meta-analysis where appropriate. Using the variability of test thresholds, we used the hierarchical summary receiver operating characteristic (HSROC) model for all eligible tests (except the circulating cathodic antigen (CCA) POC for S. mansoni, where the bivariate random-effects model was more appropriate). We investigated heterogeneity, and carried out indirect comparisons where data were sufficient. Results for sensitivity and specificity are presented as percentages with 95% confidence intervals (CI). Main results We included 90 studies; 88 from field settings in Africa. The median S. haematobium infection prevalence was 41% (range 1% to 89%) and 36% for S. mansoni (range 8

  4. Spatio-Temporal Patterns of Schistosomiasis Japonica in Lake and Marshland Areas in China: The Effect of Snail Habitats

    PubMed Central

    Hu, Yi; Gao, Jie; Chi, Meina; Luo, Can; Lynn, Henry; Sun, Liqian; Tao, Bo; Wang, Decheng; Zhang, Zhijie; Jiang, Qingwu

    2014-01-01

    The progress of the integrated control policy for schistosomiasis implemented since 2005 in China, which is aiming at reducing the roles of bovines and humans as infection sources, may be challenged by persistent presence of infected snails in lake and marshland areas. Based on annual parasitologic data for schistosomiasis during 2004–2011 in Xingzi County, a spatio-temporal kriging model was used to investigate the spatio-temporal pattern of schistosomiasis risk. Results showed that environmental factors related to snail habitats can explain the spatio-temporal variation of schistosomiasis. Predictive maps of schistosomiasis risk illustrated that clusters of the disease fluctuated during 2004–2008; there was an extensive outbreak in 2008 and attenuated disease occurrences afterwards. An area with an annually constant cluster of schistosomiasis was identified. Our study suggests that targeting snail habitats located within high-risk areas for schistosomiasis would be an economic and sustainable way of schistosomiasis control in the future. PMID:24980498

  5. Schistosomiasis japonica: modelling as a tool to explore transmission patterns.

    PubMed

    Xu, Jun-Fang; Lv, Shan; Wang, Qing-Yun; Qian, Men-Bao; Liu, Qin; Bergquist, Robert; Zhou, Xiao-Nong

    2015-01-01

    Modelling is an important tool for the exploration of Schistosoma japonicum transmission patterns. It provides a general theoretical framework for decision-makers and lends itself specifically to assessing the progress of the national control programme by following the outcome of surveys. The challenge of keeping up with the many changes of social, ecological and environmental factors involved in control activities is greatly facilitated by modelling that can also indicate which activities are critical and which are less important. This review examines the application of modelling tools in the epidemiological study of schistosomiasis japonica during the last 20 years and explores the application of enhanced models for surveillance and response. Updated and timely information for decision-makers in the national elimination programme is provided but, in spite of the new modelling techniques introduced, many questions remain. Issues on application of modelling are discussed with the view to improve the current situation with respect to schistosomiasis japonica.

  6. Schistosomiasis: Geospatial Surveillance and Response Systems in Southeast Asia

    NASA Astrophysics Data System (ADS)

    Malone, John; Bergquist, Robert; Rinaldi, Laura; Xiao-nong, Zhou

    2016-10-01

    Geographic information system (GIS) and remote sensing (RS) from Earth-observing satellites offer opportunities for rapid assessment of areas endemic for vector-borne diseases including estimates of populations at risk and guidance to intervention strategies. This presentation deals with GIS and RS applications for the control of schistosomiasis in China and the Philippines. It includes large-scale risk mapping including identification of suitable habitats for Oncomelania hupensis, the intermediate host snail of Schistosoma japonicum. Predictions of infection risk are discussed with reference to ecological transformations and the potential impact of climate change and the potential for long-term temperature increases in the North as well as the impact on rivers, lakes and water resource developments. Potential integration of geospatial mapping and modeling in schistosomiasis surveillance and response systems in Asia within Global Earth Observation System of Systems (GEOSS) guidelines in the health societal benefit area is discussed.

  7. Bilateral Tubal Gestation Associated with Schistosomiasis in an African Woman

    PubMed Central

    Odubamowo, K. H.; Akinpelu, O. M.; Lawal, O. O.; Okolo, C. A.; Odukogbe, A. A.; Adekunle, A. O.

    2014-01-01

    Background. The incidence of tubal ectopic gestation caused by schistosomiasis induced tubal pathology is undocumented in this environment, which may be due to rarity of this pathology. Bilateral tubal gestation is common in patients that have undergone in vitro fertilization. We report a hitherto undocumented case of spontaneous bilateral ectopic gestation following tubal schistosomiasis. Case Report. Mrs. OB was a 32-year-old G4P3+0 (3 alive) woman who complained of abdominal pain and bleeding per vaginam of 4 and 2 days' duration respectively following 8 weeks of amenorrhea. A clinical impression of ruptured ectopic gestation was confirmed by ultrasound scanning. She had bilateral salpingectomy with histology of specimens showing bilateral ectopic gestation with Schistosoma haematobium induced salpingitis (findings of Schistosoma haematobium ova noted on slide). Conclusion. Schistosoma induced salpingitis is a rare but possible cause of bilateral tubal gestation. PMID:25580321

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

    PubMed Central

    Leite, Luiz Arthur Calheiros; Pimenta Filho, Adenor Almeida; Ferreira, Rita de Cássia dos Santos; da Fonseca, Caíque Silveira Martins; dos Santos, Bianka Santana; Montenegro, Silvia Maria Lucena; Lopes, Edmundo Pessoa de Almeida; Domingues, Ana Lúcia Coutinho; Owen, James Stuart; Lima, Vera Lucia de Menezes

    2015-01-01

    Background 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. Methodology/Principal Findings 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. Conclusion/Significance 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. PMID:26267788

  9. Partial allelotype of schistosomiasis-associated bladder cancer.

    PubMed

    Shaw, M E; Elder, P A; Abbas, A; Knowles, M A

    1999-03-01

    In Egypt and other regions of the Middle East where the trematode Schistosoma haematobium is endemic, bladder cancer is the most common adult cancer. Unlike bladder cancers in Western countries, which are predominantly transitional-cell carcinoma (TCC), these schistosomiasis-associated bladder cancers are predominantly squamous-cell carcinoma (SCC). Our aim was to assess a large series of schistosomiasis-associated bladder tumours for genetic alterations commonly found in TCC in the United Kingdom and the United States. We have carried out a partial allelotype of 70 tumours from patients with schistosomiasis. LOH was found on all chromosome arms studied (3p, 4p, 4q, 8p, 9p, 9q, 11p, 11q, 13q, 14q, 17p, 18q). The most frequent regions of LOH were 9p (65%), 17p (58%), 3p (40%), 9q (39%) and 8p (37%). LOH on 17p, where the TP53 gene is located, was more common in Egyptian TCC than in SCC. Similarly, 8p LOH was more common in TCC than SCC. The most striking difference between this group of tumours and TCCs from the United Kingdom and the United States was the high frequency of 9p LOH in the region of the CDKN2 gene (65%) and the relatively low frequency of 9q LOH (39%); 15 of 43 tumours with LOH of at least one marker on chromosome 9 showed LOH of 9p only. This suggests that a 9p gene, possibly CDKN2, may contribute to the development of the majority of schistosomiasis-associated bladder tumours but that genes on 9q play a much less important role.

  10. Crohn’s disease and schistosomiasis: a rare association

    PubMed Central

    Limaiem, Faten; Sassi, Asma; Mzabi, Sabeh

    2016-01-01

    Schistosomiasis is a chronic enteropathogenic disease caused by blood flukes of the genus Schistosoma. Coexistence of schistosomiasis with Crohn's disease is very rare. To the best of our knowledge, this association has been described in literature only once. A 20-year-old male patient with a past medical history of appendectomy and ileocecal Crohn's disease, presented with abdominal pain and vomiting. Ileocolonoscopy showed an ulcerated and congested appearance of the upper rectum and sigmoid. Computed tomography scan revealed a circumferential thickening of the terminal ileum with luminal stenosis. Histopathological examination of the biopsy specimens revealed a focally ulcerated colonic epithelium. The lamina propria was fibrous harbouring a polymorphic inflammatory infiltrate including lymphocytes and plasma cells organized in lymphoid follicles admixed with eosinophils and neutrophils. In the submucosa, there were two well-preserved schistosoma eggs surrounded by a thick shell with a barely visible terminal spine. The final pathological diagnosis was colonic schistosomiasis associated with Crohn's disease. The patient underwent an ileocecal resection for stenosis of the terminal ileum complicated with enterocutaneous fistula. The postoperative course was uneventful. A stool examination and serology tests were planned for this patient who was lost to follow-up. PMID:28292086

  11. Epidemiological and control aspects of schistosomiasis in Brazilian endemic areas.

    PubMed

    Coura, J R; Amaral, R S

    2004-01-01

    The present work analyzes the epidemiology of schistosomiasis in Brazil, its expansion, the attempts to control the disease, and the overall difficulties. The authors present the distribution of schistosomiasis intermediary hosts in Brazil, the migration routes of the human population, and disease distribution in highly and lowly endemic areas and isolated foci. They also analyze the controlling programs developed from 1977 to 2002, indicating the prevalence evolution and the reduction of disease morbi-mortality. In addition, the authors also evaluate controlling methods and conclude that: (a) no isolated method is able to control schistosomiasis, and every controlling program should consider the need of a multidisciplinary application of existing methods; (b) in long term, basic sanitation, potable water supply, as well as sanitary education, and community effective participation are important for infection control; (c) in short term, specific treatment at endemic areas, associated with control of intermediary hosts at epidemiologically important foci, are extremely relevant for controlling disease morbidity, although not enough for interrupting infection transmission.

  12. Health education for children in the control of schistosomiasis.

    PubMed

    Schall, V T

    1987-01-01

    Health education for children is an important measure in the control of schistosomiasis especially considering the characteristics of the disease during childhood, such as high prevalence, high percent of treatment resistance, high rates of egg elimination and high level of reinfection, as reported in studies conducted in endemic areas. All of these facts indicate that children play a role in the maintenance and transmission of schistosomiasis. Historically in Brazil, Health Education concerning the major Brazilian endemies consists of a kind of vertical, interventionist and temporary action. An alternative would be to create a permanent health education process by assigning health education teachers to elementary schools. This would require expansion and improvement of teacher training and the development of programs taking into account: 1) the cognitive aspects of the child, the child's perception of reality and of the health/illness process; 2) the adaptation of instruction means and materials to the age group; 3) a "pedagogy of liberation" approach emphasizing the possibility of transforming life conditions since schistosomiasis is related to the lack of public services such as basic sanitation and clean domestic water supply.

  13. Schistosomiasis in Egypt: A never-ending story?

    PubMed

    Othman, Ahmad A; Soliman, Rasha H

    2015-08-01

    Schistosomiasis has plagued the Egyptian population since the antiquity. The disease is still a public health problem in Egypt, despite the tendency of being overlooked. In the first part of this review, the past and current trends of schistosomiasis in Egypt are reviewed, including history, epidemiology, morbidity, therapy, and control of the disease. Most of these aspects are more or less relevant to other schistosome-endemic regions all over the world. As only one drug is currently available for individual treatment and preventive mass chemotherapy, the quest for complementary measures is urgently warranted. Indeed, one promising approach is the discovery of a vaccine. Herein, we point out the efforts of the Egyptian scientists to develop an efficacious and affordable vaccine against schistosomiasis - a step forward in the battle of elimination of Schistosoma infection. Based on the candidate vaccine antigens, four types of vaccine formulations are discussed: purified antigen vaccines, DNA constructs, attenuated cercariae, and excretory-secretory antigen vaccines. Finally, this review provides insights into this ancient seemingly long-lasting parasitic disease.

  14. New endemic foci of schistosomiasis infections in the Philippines.

    PubMed

    Leonardo, Lydia; Rivera, Pilarita; Saniel, Ofelia; Antonio Solon, Juan; Chigusa, Yuichi; Villacorte, Elena; Christoper Chua, James; Moendeg, Kharleezelle; Manalo, Daria; Crisostomo, Bobby; Sunico, Louie; Boldero, Nicasio; Payne, Lara; Hernandez, Leda; Velayudhan, Raman

    2015-01-01

    Schistosomiasis affects 28 provinces in the Philippines found along the southeastern part where there is continuous rainfall throughout the year. In 2002 and 2005 respectively, two new endemic foci were reported in the northernmost (Gonzaga, Cagayan) and central (Calatrava, Negros Occidental) parts of the country. This study conducted in March 2008-March 2009 confirmed the presence of the disease by determining its prevalence using four diagnostic tests - Kato-Katz, circumoval precipitin test (COPT), ELISA and ultrasonography. Oncomelania hupensis quadrasi was identified through snail surveys conducted in possible snail habitats in the seven new endemic villages. Animal surveys through stool examination confirmed the presence of schistosomiasis infection in animals in Gonzaga but not in Calatrava. Compared to Calatrava, Gonzaga demonstrated markedly higher prevalence of schistosomiasis using all four diagnostic methods. Proximity of snail habitats to human habitation including higher snail density and snail infection rate could be responsible for the high prevalence. Snail sites were more widespread in Gonzaga whereas those in Calatrava were confined only in areas not frequented by the general population except by farmers. GIS maps showing spatial distribution of snails in Gonzaga and Calatrava indicated differences in elevation among the snail sites. It is hypothesized that the snail intermediate host has been in these sites for sometime but discovered only lately. Migration of people from endemic provinces into Gonzaga and Calatrava brought in cases and in the presence of snail intermediate hosts, emergence of disease was just a matter of time.

  15. Rural tourism: a risk factor for schistosomiasis transmission in Brazil.

    PubMed

    Enk, Martin Johannes; Amaral, Graciela Larissa; Costa e Silva, Matheus Fernandes; Silveira-Lemos, Denise; Teixeira-Carvalho, Andréa; Martins-Filho, Olindo Assis; Correa-Oliveira, Rodrigo; Gazinnelli, Giovanni; Coelho, Paulo Marcos Zech; Massara, Cristiano Lara

    2010-07-01

    This paper reports an outbreak of acute schistosomiasis among 38 tourists who rented a country house in the district of Igarapé, the metropolitan region of Belo Horizonte, Brazil, during a holiday period in 2006. A total number of 32 individuals were positive for Schistosoma mansoni. Results of stool examinations revealed individual S. mansoni egg counts per gram of faeces (epg) ranging from 4-768 epg with a geometric mean egg count of 45. The most frequent clinical symptoms were abdominal pain (78.1%), headache (75%), fever (65.6%), dry cough (65.2%) and both diarrhoea and asthenia (59.4%). A malacological survey of the area, where 22 specimens of Biomphalaria glabrata were collected, revealed three (13.6%) specimens eliminating Schistosoma cercariae. This investigation re-confirms a recently described pattern of schistosomiasis infection, resulting in the acute form of the disease and connected to rural tourism, which contributes to the spread of the disease among the middle-class and into non-endemic areas. The lack of specific knowledge about acute schistosomiasis among health services causes an increased number of unnecessary diagnostic procedures and delays in accurate diagnosis and treatment, resulting in considerable discomfort for the patients.

  16. High rate of schistosomiasis in travelers after a brief exposure to the high-altitude Nyinambuga crater lake, Uganda.

    PubMed

    Lachish, Tamar; Tandlich, Moshik; Grossman, Tamar; Schwartz, Eli

    2013-11-01

    Travel-related schistosomiasis is usually associated with prolonged freshwater exposure. Until recently, Uganda's crater lakes were considered schistosomiasis free due to their high-altitude location. We describe an outbreak of acute schistosomiasis after a brief exposure (mean, 22 ± 9.5 minutes) to a high-altitude crater lake.

  17. Global assessment of schistosomiasis control over the past century shows targeting the snail intermediate host works best

    USGS Publications Warehouse

    Sokolow, Susanne H.; Wood, Chelsea L.; Jones, Isabel J.; Swartz, Scott J.; Lopez, Melina; Hsieh, Michael H.; Lafferty, Kevin D.; Kuris, Armand M.; Rickards, Chloe; De Leo, Giulio A.

    2016-01-01

    Snail control has been the most effective way to reduce schistosomiasis prevalence. Despite evidence that snail control leads to long-term disease reduction and elimination, most current schistosomiasis control efforts emphasize MDA using praziquantel over snail control. Combining drug-based control programs with affordable snail control seems the best strategy for eliminating schistosomiasis.

  18. Impact of Annual Praziquantel Treatment on Urogenital Schistosomiasis in a Seasonal Transmission Focus in Central Senegal

    PubMed Central

    Senghor, Bruno; Diaw, Omar Talla; Doucoure, Souleymane; Seye, Mouhamadane; Diallo, Adiouma; Talla, Idrissa; Bâ, Cheikh T.; Sokhna, Cheikh

    2016-01-01

    In Sub-Saharan Africa, urogenital schistosomiasis remains a significant public health problem, causing 150.000 deaths/year with approximately 112 million cases diagnosed. The Niakhar district is a disease hotspot in central Senegal where transmission occurs seasonally with high prevalences. The aim of this study was to determine the effect of annual treatment over 3 years on the seasonal transmission dynamics of S. haematobium in 9 villages in the Niakhar district. Adults and children aged between 5 and 60 years were surveyed from 2011 to 2014. Urine samples were collected door-to-door and examined for S. haematobium eggs at baseline in June 2011, and all participants were treated in August 2011 with PZQ (40 mg/kg). After this initial examination, evaluations were conducted at 3 successive time points from September 2011 to March 2014, to measure the efficacy of the annual treatments and the rates of reinfection. Each year, during the transmission period, from July to November-December, malacological surveys were also carried out in the fresh water bodies of each village to evaluate the infestation of the snail intermediate hosts. At baseline, the overall prevalence of S. haematobium infection was 57.7%, and the proportion of heavy infection was 45.3%, but one month after the first treatment high cure rates (92.9%) were obtained. The overall infection prevalence and proportion of heavy infection intensities were drastically reduced to 4.2% and 2.3%, respectively. The level of the first reinfection in February-March 2012 was 9.5%. At follow-up time points, prevalence levels varied slightly between reinfection and treatment from 9.5% in June 2012 to 0.3% in March 2013, 11.2 in June 2013, and 10.1% April 2014. At the end of the study, overall prevalence was significantly reduced from 57.7% to 10.1%. The overall rate of infested Bulinid snails was reduced after repeated treatment from 0.8% in 2012 to 0.5% in 2013. Repeated annual treatments are suggested to have a

  19. Impact of Annual Praziquantel Treatment on Urogenital Schistosomiasis in a Seasonal Transmission Focus in Central Senegal.

    PubMed

    Senghor, Bruno; Diaw, Omar Talla; Doucoure, Souleymane; Seye, Mouhamadane; Diallo, Adiouma; Talla, Idrissa; Bâ, Cheikh T; Sokhna, Cheikh

    2016-03-01

    In Sub-Saharan Africa, urogenital schistosomiasis remains a significant public health problem, causing 150.000 deaths/year with approximately 112 million cases diagnosed. The Niakhar district is a disease hotspot in central Senegal where transmission occurs seasonally with high prevalences. The aim of this study was to determine the effect of annual treatment over 3 years on the seasonal transmission dynamics of S. haematobium in 9 villages in the Niakhar district. Adults and children aged between 5 and 60 years were surveyed from 2011 to 2014. Urine samples were collected door-to-door and examined for S. haematobium eggs at baseline in June 2011, and all participants were treated in August 2011 with PZQ (40 mg/kg). After this initial examination, evaluations were conducted at 3 successive time points from September 2011 to March 2014, to measure the efficacy of the annual treatments and the rates of reinfection. Each year, during the transmission period, from July to November-December, malacological surveys were also carried out in the fresh water bodies of each village to evaluate the infestation of the snail intermediate hosts. At baseline, the overall prevalence of S. haematobium infection was 57.7%, and the proportion of heavy infection was 45.3%, but one month after the first treatment high cure rates (92.9%) were obtained. The overall infection prevalence and proportion of heavy infection intensities were drastically reduced to 4.2% and 2.3%, respectively. The level of the first reinfection in February-March 2012 was 9.5%. At follow-up time points, prevalence levels varied slightly between reinfection and treatment from 9.5% in June 2012 to 0.3% in March 2013, 11.2 in June 2013, and 10.1% April 2014. At the end of the study, overall prevalence was significantly reduced from 57.7% to 10.1%. The overall rate of infested Bulinid snails was reduced after repeated treatment from 0.8% in 2012 to 0.5% in 2013. Repeated annual treatments are suggested to have a

  20. [Discussion on water conservancy projects and schistosomiasis control in Poyang Lake area].

    PubMed

    Liu, Dao-Nan

    2013-02-01

    According to the schistosomiasis endemic situation in the Poyang Lake area, this paper analyzes the relationship between the water conservancy projects and schistosomiasis control, and reviews and discusses the effects of the Water Level Control Project of Poyang Lake, the Lake Dike Slope Hardening Project, and the Lifting Delta and Descending Beach Project on Oncomelania snail control.

  1. From innovation to application: social-ecological context, diagnostics, drugs and integrated control of schistosomiasis.

    PubMed

    Utzinger, Jürg; N'goran, Eliézer K; Caffrey, Conor R; Keiser, Jennifer

    2011-09-01

    Compared to malaria, tuberculosis and HIV/AIDS, schistosomiasis remains a truly neglected tropical disease. Schistosomiasis, perhaps more than any other disease, is entrenched in prevailing social-ecological systems, since transmission is governed by human behaviour (e.g. open defecation and patterns of unprotected surface water contacts) and ecological features (e.g. living in close proximity to suitable freshwater bodies in which intermediate host snails proliferate). Moreover, schistosomiasis is intimately linked with poverty and the disease has spread to previously non-endemic areas as a result of demographic, ecological and engineering transformations. Importantly though, thanks to increased advocacy there is growing awareness, financial and technical support to control and eventually eliminate schistosomiasis as a public health problem at local, regional and global scales. The purpose of this review is to highlight recent progress made in innovation, validation and application of new tools and strategies for research and integrated control of schistosomiasis. First, we explain that schistosomiasis is deeply embedded in social-ecological systems and explore linkages with poverty. We then summarize and challenge global statistics, risk maps and burden estimates of human schistosomiasis. Discovery and development research pertaining to novel diagnostics and drugs forms the centrepiece of our review. We discuss unresolved issues and emerging opportunities for integrated and sustainable control of schistosomiasis and conclude with a series of research needs.

  2. Heat Shock Protein HSP27 Secretion by Ovarian Cancer Cells Is Linked to Intracellular Expression Levels, Occurs Independently of the Endoplasmic Reticulum Pathway and HSP27's Phosphorylation Status, and Is Mediated by Exosome Liberation

    PubMed Central

    Klinkmann, Gerd; Diesing, Karoline; Koensgen, Dominique; Burchardt, Martin

    2017-01-01

    The heat shock protein HSP27 has been correlated in ovarian cancer (OC) patients with aggressiveness and chemoresistance and, therefore, represents a promising potential biomarker for OC diagnosis, prognosis, and treatment response. Notably, secretion of soluble HSP27 has been described by a few cell types and may take place as well in OC cells. Therefore, we studied HSP27 secretion mechanisms under diverse cellular conditions in an OC cell model system. Secretion of HSP27 was characterized after overexpression of HSP27 by transfected plasmids and after heat shock. Intra- and extracellular HSP27 amounts were assessed by Western blotting and ELISA. Protein secretion was blocked by brefeldin A and the impact of the HSP27 phosphorylation status was analyzed overexpressing HSP27 phosphomutants. The present study demonstrated that HSP27 secretion by OVCAR-3 and SK-OV-3 cells depends on intracellular HSP27 concentrations. Moreover, HSP27 secretion is independent of the endoplasmic reticulum secretory pathway and HSP27 phosphorylation. Notably, analysis of OC cell-born exosomes not only confirmed the concentration-dependent correlation of HSP27 expression and secretion but also demonstrated a concentration-dependent incorporation of HSP27 protein into exosomes. Thus, secreted HSP27 may become more important as an extracellular factor which controls the tumor microenvironment and might be a noninvasive biomarker. PMID:28325957

  3. Schistosomiasis Elimination Strategies and Potential Role of a Vaccine in Achieving Global Health Goals

    PubMed Central

    Mo, Annie X.; Agosti, Jan M.; Walson, Judd L.; Hall, B. Fenton; Gordon, Lance

    2014-01-01

    In March 2013, the National Institute of Allergy and Infectious Diseases and the Bill and Melinda Gates Foundation co-sponsored a meeting entitled “Schistosomiasis Elimination Strategy and Potential Role of a Vaccine in Achieving Global Health Goals” to discuss the potential role of schistosomiasis vaccines and other tools in the context of schistosomiasis control and elimination strategies. It was concluded that although schistosomiasis elimination in some focal areas may be achievable through current mass drug administration programs, global control and elimination will face several significant scientific and operational challenges, and will require an integrated approach with other, additional interventions. These challenges include vector (snail) control; environmental modification; water, sanitation, and hygiene; and other future innovative tools such as vaccines. Defining a clear product development plan that reflects a vaccine strategy as complementary to the existing control programs to combat different forms of schistosomiasis will be important to develop a vaccine effectively. PMID:24402703

  4. Evolution of the National Schistosomiasis Control Programmes in The People's Republic of China.

    PubMed

    Xu, J; Steinman, P; Maybe, D; Zhou, X-N; Lv, S; Li, S-Z; Peeling, R

    2016-01-01

    Schistosomiasis japonica is caused by the parasitic trematode Schistosoma japonicum. It is endemic in The People's Republic of China and has significant impact on human health and socioeconomic development in certain regions. Over the last six decades, the national control programmes evolved in remarkable ways and brought schistosomiasis japonica largely under control. We describe the history and evolution of schistosomiasis control in The People's Republic of China, with an emphasis on shifts in control strategies that evolved with new insights into the biology of the parasite and its intermediate hosts, and the epidemiology of the disease in the country. We also highlight the achievements in controlling the disease in different socioecological settings, and identify persisting challenges to fully eliminate schistosomiasis japonica from the country. To reach the goal of schistosomiasis elimination, further integration of interventions, multisector collaboration, sensitive and effective surveillance are needed to strengthen.

  5. [Application of Big Data Mining Technology in Monitoring and Early-warning of Schistosomiasis].

    PubMed

    Yang, Kun; Li, Shi-zhu

    2015-12-01

    The prevalence of schistosomiasis will soon be controlled to a low level in China. It is therefore imperative to establish a more sensitive and effective early warning system for schistosomiasis, so as to consolidate the achievements of the disease control. By covering four topics including the importance of early warning system for schistosomiasis and its research direction, as well as recent development in big data mining and its application in monitoring and early-warning of schistosomiasis, this review discusses the feasibility of data mining technology for monitoring and early warning of the disease. It is hoped that this technology would increase the efficacy of studies on monitoring and early warning, and promote the elimination of schistosomiasis in China.

  6. Schistosomiasis elimination strategies and potential role of a vaccine in achieving global health goals.

    PubMed

    Mo, Annie X; Agosti, Jan M; Walson, Judd L; Hall, B Fenton; Gordon, Lance

    2014-01-01

    In March 2013, the National Institute of Allergy and Infectious Diseases and the Bill and Melinda Gates Foundation co-sponsored a meeting entitled "Schistosomiasis Elimination Strategy and Potential Role of a Vaccine in Achieving Global Health Goals" to discuss the potential role of schistosomiasis vaccines and other tools in the context of schistosomiasis control and elimination strategies. It was concluded that although schistosomiasis elimination in some focal areas may be achievable through current mass drug administration programs, global control and elimination will face several significant scientific and operational challenges, and will require an integrated approach with other, additional interventions. These challenges include vector (snail) control; environmental modification; water, sanitation, and hygiene; and other future innovative tools such as vaccines. Defining a clear product development plan that reflects a vaccine strategy as complementary to the existing control programs to combat different forms of schistosomiasis will be important to develop a vaccine effectively.

  7. Reduced Peripheral PGE2 Biosynthesis in Plasmodium falciparum Malaria Occurs through Hemozoin-Induced Suppression of Blood Mononuclear Cell Cyclooxygenase-2 Gene Expression via an Interleukin-10–Independent Mechanism

    PubMed Central

    Keller, Christopher C; Hittner, James B; Nti, Benjamin K; Weinberg, J Brice; Kremsner, Peter G; Perkins, Douglas J

    2004-01-01

    through inhibition of de novo COX-2 transcripts via molecular mechanisms independent of increased IL-10 production. PMID:15502882

  8. Self-diagnosis as a possible basis for treating urinary schistosomiasis: a study of schoolchildren in a rural area of the United Republic of Tanzania. Partnership for Child Development.

    PubMed Central

    1999-01-01

    A questionnaire for schoolchildren about symptoms of urinary schistosomiasis is becoming widely used to identify schools where the prevalence of infection with Schistosoma haematobium is greater than 50%, the threshold for applying mass treatment. This strategy typically leaves many schools without treatment even though some of the children have urinary schistosomiasis and blood in urine. We examined data collected during an evaluation of a school health programme in Tanga Region, the United Republic of Tanzania, to determine whether self-diagnosis could be used as a basis for giving treatment. Over 2300 children in 15 schools were asked by a nurse whether they had kichocho (urinary schistosomiasis) and their answers were compared with the results of tests for visible and occult blood in urine, and microscopy for S. haematobium eggs. An average of 75% of children were correct in their self-diagnosis (95% confidence interval (CI) = 72-78%), while 3% gave a false-positive diagnosis (95% CI = 2-4%). The remaining 22% gave a false-negative diagnosis (95% CI = 20-25%) and would not have been treated, although most of these children were lightly infected. These proportions were independent of a wide range of prevalence levels (7-77%) and intensity of infection (23-827 eggs per 10 ml of urine). Self-reported schistosomiasis might thus be used to treat children in schools where mass treatment is not applied. PMID:10427932

  9. Environmental inducers of schistosomiasis mansoni in Campinas, Brazil.

    PubMed

    Anaruma Filho, Francisco; Sant'Ana, João Moreno; dos Santos, Rozely Ferreira; Castagna, Cláudio Luiz

    2010-11-01

    Human occupation/activity in the suburbs of the large cities in Brazil, together with high social vulnerability associated with poor living conditions, influence the dynamics of schistosomiasis mansoni as well as several other emerging and re-emerging diseases. Previous notification data surveys for Campinas, São Paulo state, Brazil, carried out by the Information System for Notification Disease, show that there are distinct prevalence differences across healthcare districts of the city. This paper supports the hypothesis that the distribution of schistosomiasis is not random and that the centralized location of cases are linked to human behaviour, in particular to human activities that interfere with basic landscape structure. This paper analyzes the spatial patterns of the parasitic worm Schistosoma mansoni and its intermediate host Biomphalaria comparing disease prevalence with natural conditions and the current pattern of territory occupation by the population. The spatial and hierarchical distribution of factors related to the environmental conditions and land use that indicate the risk for schistosomiasis has been surveyed. It was found that landscape characteristics define the areas at risk for this endemic disease and, as a result, a risk map comprising different risk classes was established. This risk map highlights the regions prone to become new foci for infection or that serves to maintain an existing focus. The research approach used attempts to introduce "geotechnology", i.e. a social application in which better knowledge about these foci, designated endemic "hot spots" can assist preventive public intervention measures in a way that is inexpensive and easy to handle.

  10. Schistosomiasis vaccines: Farewell to the God of Plague?

    PubMed

    Taylor, M G

    1994-10-01

    Control and even eradication of schistosomiasis have been achieved in some countries using integrated measures but this disease remains endemic in 74 countries with 600 million at risk of whom 200 million are currently infected. The application of control measures, particularly population-based chemotherapy, has in many countries greatly reduced the incidence of serious disease manifestations, but vaccines are urgently needed to supplement existing control measures. Great advances are being made in vaccine development and the first clinical trials are expected to begin shortly.

  11. Prevention and control of schistosomiasis: a current perspective

    PubMed Central

    Inobaya, Marianette T; Olveda, Remigio M; Chau, Thao NP; Olveda, David U; Ross, Allen GP

    2014-01-01

    Schistosomiasis is a neglected tropical disease that ranks second only to malaria in terms of human suffering in the tropics and subtropics. Five species are known to infect man and there are currently over 240 million people infected worldwide. The cornerstone of control to date has been mass drug administration with 40 mg/kg of praziquantel but there are problems with this approach. Human and bovine vaccines are in various stages of development. Integrated control, targeting the life cycle, is the only approach that will lead to sustainability and future elimination. PMID:25400499

  12. Progress in the national schistosomiasis control programme of Iran

    PubMed Central

    Massoud, J.; Arfaa, F.; Farahmandian, I.; Ardalan, A.; Mansoorian, A.

    1982-01-01

    A combination of chemotherapy and mollusciciding has been used in Khuzestan, south-west Iran, since 1966, to try to control urinary schistosomiasis. The total amount of molluscicide used each year varied between 702 and 3505 kg and between 287 and 1320 infected persons were detected and treated annually. The prevalence of infection has gradually declined from 8.3% in 1970 to 0.7% in 1979. Similarly, the incidence of infection among schoolchildren decreased from 3.5% in 1970 to 0.7% in 1979. The proportion of Bulinus-infested habitats also decreased from 10% in 1971 to 2.4% in 1979. PMID:6982780

  13. Schistosomiasis in Omo National Park of southwest Ethiopia.

    PubMed

    Fuller, G K; Lemma, A; Haile, T

    1979-05-01

    Schistosomiasis mansoni infection was found in more than 50 tourists who had visited Omo National Park, Ethiopia, and bathed and swum in the Mui River. A survey revealed Schistosoma mansoni infection in 41% of Park residents and in 33% of the neighboring Suri people. Eggs were found in stools and adult worms at autopsy of wild Papio anubis and Cercopithecus aethiops. Trematode larvae were found in 27% of Biomphalaria pfeifferi snails found in the Mui River. The source of the disease and the implications of its spread with the future development of the Omo Valley are discussed.

  14. Naturally occurring chemical carcinogens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Natural products are chemicals found in nature which have unique pharmacological effects. Humans are exposed to many of these bioactive naturally occurring chemicals via the air breathed, the water drunk and the food eaten. Exposure also occurs in clinical settings. Naturally occurring chemicals ...

  15. Testing of Compounds for Efficacy against Schistosomiasis.

    DTIC Science & Technology

    1986-07-22

    an anthelmentic which is active against most tapeworm species including the beef tapeworm (Taenia S .inat), the pork tapeworm (I. solium), the fish... tapeworm (Diphyllobothrium latum) and the dwarf tapeworm (Imeno,pis nana) (15,16). B. Test Compound Solvent or Vehicle. Pharmaceutical grade absolute...treatment of persons with tapeworm infections. No toxic effects are known to occur in man. The results obtained with the undiluted preparation suggests

  16. Have You Heard of Schistosomiasis? Knowledge, Attitudes and Practices in Nampula Province, Mozambique

    PubMed Central

    Rassi, Christian; Kajungu, Dan; Martin, Sandrine; Arroz, Jorge; Tallant, Jamie; Zegers de Beyl, Celine; Counihan, Helen; Newell, James N.; Phillips, Anna; Whitton, Jane; Muloliwa, Artur Manuel; Graham, Kirstie

    2016-01-01

    Background Schistosomiasis is a parasitic disease which affects almost 300 million people worldwide each year. It is highly endemic in Mozambique. Prevention and control of schistosomiasis relies mainly on mass drug administration (MDA), as well as adoption of basic sanitation practices. Individual and community perceptions of schistosomiasis are likely to have a significant effect on prevention and control efforts. In order to establish a baseline to evaluate a community engagement intervention with a focus on schistosomiasis, a survey to determine knowledge, attitudes and practices relating to the disease was conducted. Methodology/Principal Findings A representative cross-sectional household survey was carried out in four districts of Nampula province, Mozambique. Interviews were conducted in a total of 791 households, using a structured questionnaire. While awareness of schistosomiasis was high (91%), correct knowledge of how it is acquired (18%), transmitted (26%) and prevented (13%) was low among those who had heard of the disease. Misconceptions, such as the belief that schistosomiasis is transmitted through sexual contact (27%), were common. Only about a third of those who were aware of the disease stated that they practiced a protective behaviour and only a minority of those (39%) reported an effective behaviour. Despite several rounds of MDA for schistosomiasis in the recent past, only a small minority of households with children reported that at least one of them had received a drug to treat the disease (9%). Conclusion/Significance Poor knowledge of the causes of schistosomiasis and how to prevent it, coupled with persisting misconceptions, continue to pose barriers to effective disease prevention and control. To achieve high levels of uptake of MDA and adoption of protective behaviours, it will be essential to engage individuals and communities, improving their understanding of the causes and symptoms of schistosomiasis, recommended prevention

  17. A new global strategy for the elimination of schistosomiasis.

    PubMed

    Ross, Allen G P; Chau, Thao N; Inobaya, Marianette T; Olveda, Remigio M; Li, Yuesheng; Harn, Donald A

    2017-01-01

    Mass drug administration utilising a single oral dose of 40mg/kg of praziquantel (PZQ) has been endorsed and advocated by the World Health Organisation (WHO) for the global control and elimination of schistosomiasis. However, this strategy is failing primarily because the drugs are not getting to the people who need them the most. The current global coverage is 20%, the drug compliance rate is less than 50%, and the drug efficacy is approximately 50%. Thus in reality, only about 5% of the reservoir human population is actually receiving intermittent chemotherapy. Despite claims that more of the drug will soon be made available the current strategy is inherently flawed and will not lead to disease elimination. We discuss the many practical issues related to this global strategy, and advocate for an integrated control strategy targeting the life cycle and the most at-risk. Moreover, we discuss how an integrated control package for schistosomiasis should fit within a larger integrated health package for rural and remote villages in the developing world. A holistic health system approach is required to achieve sustainable control and ultimately disease elimination.

  18. Schistosomiasis mansoni in Burundi: progress in its control since 1985.

    PubMed Central

    Engels, D.; Ndoricimpa, J.; Gryseels, B.

    1993-01-01

    Described is the evolution of the schistosomiasis control programme in Burundi since 1985. A single round of selective population chemotherapy was carried out in the Rusizi Plain and the Bugesera focus from 1985 to 1990. The prevalences and intensities of infection as well as the number of symptomatic cases detected in general health services decreased considerably. Annual sample surveys in the treated areas showed, however, that these improvements were rapidly reversed by reinfection of the demographically changing population. Since repeated selective population chemotherapy was not sustainable in the long term, a primary health care approach was adopted. In areas with good access to basic health services, approximately 10% of all schistosomiasis cases now receive treatment annually through this approach. Yearly selective chemotherapy in primary schools in suburban Bujumbura reduced the prevalence of schistosomal infection among pupils from 23% to 9% over the period 1984-90, and this programme has now been extended to highly endemic areas in Imbo-Sud. Focal snail control produced disappointing results, and emphasis has therefore shifted towards health education and environmental control of transmission. PMID:8490984

  19. [Endemic status of schistosomiasis in People's Republic of China in 2014].

    PubMed

    Lei, Zheng-long; Zhang, Li-juan; Xu, Zhi-min; Dang, Hui; Xu, Jing; Lv, Shan; Cao, Chun-li; Li, Shi-zhu; Zhou, Xiao-nong

    2015-12-01

    This report presented the endemic status of schistosomiasis in the People's Republic of China at national level in 2014, and analyzed the data captured from the national schistosomiasis prevention and control system and 81 national schistosomiasis surveillance sites. Among the 12 provinces (municipality and autonomous region) endemic for schistosomiasis japonica in China, 5 provinces (municipality and autonomous region) of Shanghai, Zhejiang, Fujian, Guangdong and Guangxi had achieved transmission interruption, 4 provinces of Sichuan, Yunnan, Jiangsu and Hubei had achieved transmission control, and Anhui, Jiangxi and Hunan provinces were still at infection control until 2014. There were 453 counties (city, district) endemic for schistosomiasis, with 251 million residents, and 30,048 villages endemic for schistosomiasis, with 68 million 507 thousand and 3 hundred residents. Among the 453 endemic counties (city, district), 69.09% (313/453) and 29.80% (135/ 453) endemic counties (city, district) reached the transmission interruption and transmission control respectively while the number of counties (city, district) at the stage of infection control reduced from 34 in 2013 to 5 in 2014 (accounted for 1.10% of the total number of endemic counties, 5/53). Till 2014, 115,614 people were estimated to have schistosomiasis and only 2 acute schistosomiasis cases were reported. In addition, there were 30,880 advanced schistosomiasis cases documented in 2014. In 2014, a total of 9,461,348 individuals received schistosomiasis examinations and 8,270 persons were found stool positives with the reduction rate of 50.96% as compared to that (16,865 cases) in 2013. The Oncomelania hupensis snail survey was performed in 20 123 endemic villages in 2014, and the snails were detected in 5,653 villages, which accounted for 28.09% of total villages, with 13 newly detected villages with snails. The snail survey covered an area of 576,506.37 hm² and snails were found in an area of 364 324

  20. Global Assessment of Schistosomiasis Control Over the Past Century Shows Targeting the Snail Intermediate Host Works Best

    PubMed Central

    Sokolow, Susanne H.; Wood, Chelsea L.; Jones, Isabel J.; Lopez, Melina; Lafferty, Kevin D.; Kuris, Armand M.; Rickards, Chloe; De Leo, Giulio A.

    2016-01-01

    Background Despite control efforts, human schistosomiasis remains prevalent throughout Africa, Asia, and South America. The global schistosomiasis burden has changed little since the new anthelmintic drug, praziquantel, promised widespread control. Methodology We evaluated large-scale schistosomiasis control attempts over the past century and across the globe by identifying factors that predict control program success: snail control (e.g., molluscicides or biological control), mass drug administrations (MDA) with praziquantel, or a combined strategy using both. For data, we compiled historical information on control tactics and their quantitative outcomes for all 83 countries and territories in which: (i) schistosomiasis was allegedly endemic during the 20th century, and (ii) schistosomiasis remains endemic, or (iii) schistosomiasis has been "eliminated," or is "no longer endemic," or transmission has been interrupted. Principal Findings Widespread snail control reduced prevalence by 92 ± 5% (N = 19) vs. 37 ± 7% (N = 29) for programs using little or no snail control. In addition, ecological, economic, and political factors contributed to schistosomiasis elimination. For instance, snail control was most common and widespread in wealthier countries and when control began earlier in the 20th century. Conclusions/Significance Snail control has been the most effective way to reduce schistosomiasis prevalence. Despite evidence that snail control leads to long-term disease reduction and elimination, most current schistosomiasis control efforts emphasize MDA using praziquantel over snail control. Combining drug-based control programs with affordable snail control seems the best strategy for eliminating schistosomiasis. PMID:27441556

  1. From Incidentaloma to Suspicion of Malignancy: The Diverse Clinical Presentation of Gonadal Schistosomiasis mansoni

    PubMed Central

    Almeida, Laiana do Carmo; de Oliveira, Marbele Guimarães; Castro Pereira, Fábio Meira; de Bessa Júnior, José

    2013-01-01

    Schistosomiasis is the second most widespread parasitic disease in the world, second only to malaria. The usual places the Schistosoma mansoni can be found in are the rectal and sigmoidal venules, as well as other segments of the large intestine of men. It may also be present in other ectopic topographies. Gonadal schistosomiasis is an unusual presentation of Schistosomiasis mansoni and its different clinical signs and symptoms disrupt correct diagnosis and culminate in surgical treatment that is, in most cases, unnecessary. In this study, we report four cases of gonadal Schistosomiasis mansoni, two in the ovary and two in the testicles. These cases were clinically investigated as a bacterial infection, a benign neoplasm, and a suspected cancer, whilst one of them was an incidentaloma. PMID:24392230

  2. Intestinal Schistosomiasis as Unusual Aetiology for Acute Appendicitis, Nowadays a Rising Disease in Western Countries

    PubMed Central

    López de Cenarruzabeitia, I.; Landolfi, S.; Armengol Carrasco, M.

    2012-01-01

    Intestinal schistosomiasis as unusual aetiology for acute appendicitis, nowadays a rising disease in western countries. Recent changes in global migration has led to an immigration growth in our scenario, upsurging people coming from endemic areas of schistosomiasis. Schistosomal appendicitis, seldom reported in developed countries, is now an expected incrising entity in our hospitals during the near future. Due to this circumstances, we believe that schistosomiasis should be consider as a rising source for acute appendicitis in western countries. In order to illustrate this point, we present a case of a 45-years-old black man, from Africa, was admitted via A&E because of acute abdominal pain, located in right lower quadrant. Acute appendicitis was suspected, and he underwent laparotomy and appendectomy. Pathological study by microscope revealed a gangrenous appendix with abscesses and parasitic ova into the submucosal layer of the appendix, suggesting Schistosomiasis. PMID:22792502

  3. Schistosoma mansoni: a diagnostic approach to detect acute schistosomiasis infection in a murine model by PCR.

    PubMed

    Sandoval, Nidia; Siles-Lucas, Mar; Lopez Aban, Julio; Pérez-Arellano, José Luis; Gárate, Teresa; Muro, Antonio

    2006-10-01

    Schistosomiasis represents an increasing problem in non-endemic areas, due to the growing number of immigrants and to tourists contracting this disease in "off-the-beaten-track" tourism. Acute schistosomiasis is not diagnosed early due to the lack of diagnostic tools that are sufficiently sensitive enough to detect the parasite during the first weeks of infection. We have developed a diagnostic approach based on the detection of parasite DNA by polymerase chain reaction (PCR) in urine, comparing the performance of this new approach with the two currently used schistosomiasis diagnostic tools (Kato-Katz and ELISA) and the PCR in stool samples. This comparison was done in a Schistosoma mansoni murine experimental model, which permits follow up of the parasite from the acute to the chronic stage of infection. Our results suggest that this new PCR-based approach could be useful for the detection of acute schistosomiasis in easy-to-handle clinical samples such the urine.

  4. Inhibition of Notch Signaling Attenuates Schistosomiasis Hepatic Fibrosis via Blocking Macrophage M2 Polarization

    PubMed Central

    Chen, Yixiong; Zheng, Shaojiang; Zheng, Liping; Weng, Zhihong

    2016-01-01

    Macrophages play a key role in the pathogenesis of liver granuloma and fibrosis in schistosomiasis. However, the underlying mechanisms have not been fully characterized. This study revealed that the macrophages infiltrating the liver tissues in a murine model of Schistosoma japonica infection exhibited M2 functional polarization, and Notch1/Jagged1 signaling was significantly upregulated in the M2 polarized macrophages in vivo and in vitro. Furthermore, the blockade of Notch signaling pathway by a γ–secretase inhibitor could reverse macrophage M2 polarization in vitro and alleviate liver granuloma and fibrosis in the murine model of schistosomiasis. These results implied that the Notch1/Jagged1 signaling-dependent M2 polarization of macrophages might play an important role in liver granuloma and fibrosis in schistosomiasis, and the inhibition of Notch1/Jagged1 signaling might provide a novel therapeutic approach to administrate patients with schistosomiasis. PMID:27875565

  5. Optimal control analysis of malaria-schistosomiasis co-infection dynamics.

    PubMed

    Okosun, Kazeem Oare; Smith, Robert

    2017-04-01

    This paper presents a mathematical model for malaria--schistosomiasis co-infection in order to investigate their synergistic relationship in the presence of treatment. We first analyse the single infection steady states, then investigate the existence and stability of equilibria and then calculate the basic reproduction numbers. Both the single-infection models and the co-infection model exhibit backward bifurcations. We carrying out a sensitivity analysis of the co-infection model and show that schistosomiasis infection may not be associated with an increased risk of malaria. Conversely, malaria infection may be associated with an increased risk of schistosomiasis. Furthermore, we found that effective treatment and prevention of schistosomiasis infection would also assist in the effective control and eradication of malaria. Finally, we apply Pontryagin's Maximum Principle to the model in order to determine optimal strategies for control of both diseases.

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

    PubMed Central

    Guimarães, Ricardo J. P. S.; Freitas, Corina C.; Dutra, Luciano V.; Felgueiras, Carlos A.; Drummond, Sandra C.; Tibiriçá, Sandra H. C.; Oliveira, Guilherme; Carvalho, Omar S.

    2012-01-01

    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. PMID:22291716

  7. Use of indicator kriging to investigate schistosomiasis in minas gerais state, Brazil.

    PubMed

    Guimarães, Ricardo J P S; Freitas, Corina C; Dutra, Luciano V; Felgueiras, Carlos A; Drummond, Sandra C; Tibiriçá, Sandra H C; Oliveira, Guilherme; Carvalho, Omar S

    2012-01-01

    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.

  8. Applications of Spatial Technology in Schistosomiasis Control Programme in The People's Republic of China.

    PubMed

    Wang, X-Y; He, J; Yang, K; Liang, S

    2016-01-01

    Schistosomiasis, as the important parasitic disease, has caused serious threats to human health globally. The People's Republic of China has acquired significant achievements based on large-scale interventions and innovational technology. The spatial technology was introduced in 1980s and widely used in the study and control of schistosomiasis in The People's Republic of China. This chapter reviews the progress and application of spatial technology in schistosomiasis control by analysing the spatiotemporal pattern of and the impact of ecological changes on schistosomiasis transmission, which have provided the information to design and select the control strategy, and assisted the establishment of the monitoring and early warning system in The People's Republic of China, especially in the marshland and mountainous regions.

  9. The Relationship between Water, Sanitation and Schistosomiasis: A Systematic Review and Meta-analysis

    PubMed Central

    Grimes, Jack E. T.; Croll, David; Harrison, Wendy E.; Utzinger, Jürg; Freeman, Matthew C.; Templeton, Michael R.

    2014-01-01

    Background 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. Methodology 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. Principal Findings 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. Conclusions/Significance 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

  10. Pulmonary Artery Pressure, Gender, Menopause, and Pregnancy in Schistosomiasis-Associated Pulmonary Hypertension

    PubMed Central

    Armstrong, Anderson C.; Bandeira, Ângela M. P.; Correia, Luis C. L.; Melo, Humberto C. O.; Silveira, Carlos A. M.; Albuquerque, Eugênio; Moraes, Jeová C.; Silva, Antônio M. L.; Lima, João A. C.; Sobral, Dário C.

    2013-01-01

    Background Schistosomiasis-associated pulmonary arterial hypertension (SPAH) is a major concern worldwide. However, the role of gender specific contributing factors in SPAH is unknown. Objective We investigated how systolic pulmonary artery pressure (SPAP) values and the presence of severe SPAP relate to gender, menopausal status, and pregnancy history in SPAH patients. Methods Seventy-nine patients diagnosed with SPAH from 2000 to 2009 were assessed and 66 were enrolled in the study. Information about age, menopausal status, pregnancy, echocardiography-derived SPAP, and invasive mean pulmonary artery pressure (mPAP) was collected from medical records. The relation between values of SPAP and mPAP and their agreement for severe disease were assessed. Regression models assessed the association of gender, menopausal status, and pregnancy history with SPAP values and the presence of severe SPAP. Results Moderate correlation and good agreement for severe disease were found between mPAP and SPAP. Mean SPAP values were similar for men and women. A trend toward higher values of SPAP was found for non-menopausal women compared to men. Higher SPAP values were found for menopausal compared to non-menopausal women; the values were non-significant after adjustment for age. Pregnancy history had no association with SPAP. Menopause and positive pregnancy had no association with severe SPAP. Conclusion In SPAH patients, neither gender, nor menopausal status, nor pregnancy history showed independent correlation with SPAP values assessed by echocardiography. PMID:23821406

  11. Acute schistosomiasis in travelers: 14 years' experience at the Hospital for Tropical Diseases, London.

    PubMed

    Logan, Sarah; Armstrong, Margaret; Moore, Elinor; Nebbia, Gaia; Jarvis, Joseph; Suvari, Muhiddin; Bligh, John; Chiodini, Peter L; Brown, Michael; Doherty, Tom

    2013-06-01

    We report 79 cases of acute schistosomiasis. Most of these cases were young, male travelers who acquired their infection in Lake Malawi. Twelve had a normal eosinophil count at presentation and 11 had negative serology, although two had neither eosinophilia nor positive serology when first seen. Acute schistosomiasis should be considered in any febrile traveler with a history of fresh water exposure in an endemic area once malaria has been excluded.

  12. Monitoring schistosomiasis risk in East China over space and time using a Bayesian hierarchical modeling approach.

    PubMed

    Hu, Yi; Ward, Michael P; Xia, Congcong; Li, Rui; Sun, Liqian; Lynn, Henry; Gao, Fenghua; Wang, Qizhi; Zhang, Shiqing; Xiong, Chenglong; Zhang, Zhijie; Jiang, Qingwu

    2016-04-07

    Schistosomiasis remains a major public health problem and causes substantial economic impact in east China, particularly along the Yangtze River Basin. Disease forecasting and surveillance can assist in the development and implementation of more effective intervention measures to control disease. In this study, we applied a Bayesian hierarchical spatio-temporal model to describe trends in schistosomiasis risk in Anhui Province, China, using annual parasitological and environmental data for the period 1997-2010. A computationally efficient approach-Integrated Nested Laplace Approximation-was used for model inference. A zero-inflated, negative binomial model best described the spatio-temporal dynamics of schistosomiasis risk. It predicted that the disease risk would generally be low and stable except for some specific, local areas during the period 2011-2014. High-risk counties were identified in the forecasting maps: three in which the risk remained high, and two in which risk would become high. The results indicated that schistosomiasis risk has been reduced to consistently low levels throughout much of this region of China; however, some counties were identified in which progress in schistosomiasis control was less than satisfactory. Whilst maintaining overall control, specific interventions in the future should focus on these refractive counties as part of a strategy to eliminate schistosomiasis from this region.

  13. Monitoring schistosomiasis risk in East China over space and time using a Bayesian hierarchical modeling approach

    PubMed Central

    Hu, Yi; Ward, Michael P.; Xia, Congcong; Li, Rui; Sun, Liqian; Lynn, Henry; Gao, Fenghua; Wang, Qizhi; Zhang, Shiqing; Xiong, Chenglong; Zhang, Zhijie; Jiang, Qingwu

    2016-01-01

    Schistosomiasis remains a major public health problem and causes substantial economic impact in east China, particularly along the Yangtze River Basin. Disease forecasting and surveillance can assist in the development and implementation of more effective intervention measures to control disease. In this study, we applied a Bayesian hierarchical spatio-temporal model to describe trends in schistosomiasis risk in Anhui Province, China, using annual parasitological and environmental data for the period 1997–2010. A computationally efficient approach–Integrated Nested Laplace Approximation–was used for model inference. A zero-inflated, negative binomial model best described the spatio-temporal dynamics of schistosomiasis risk. It predicted that the disease risk would generally be low and stable except for some specific, local areas during the period 2011–2014. High-risk counties were identified in the forecasting maps: three in which the risk remained high, and two in which risk would become high. The results indicated that schistosomiasis risk has been reduced to consistently low levels throughout much of this region of China; however, some counties were identified in which progress in schistosomiasis control was less than satisfactory. Whilst maintaining overall control, specific interventions in the future should focus on these refractive counties as part of a strategy to eliminate schistosomiasis from this region. PMID:27053447

  14. Factors affecting knowledge of the symptoms of schistosomiasis in two rural areas near Ismailia, Egypt.

    PubMed

    Mehanna, S; Winch, P J; Rizkalla, N H; el-Sayed, H F; Abaza, S M

    1997-11-01

    The primary method of control of schistosomiasis in Egypt is through passive chemotherapy, in which people who suspect they have the disease are encouraged to go to their local health unit to be tested and treated. If people are unable to recognize the symptoms of schistosomiasis, this strategy may fail. This paper presents data on local knowledge of the symptoms of schistosomiasis from two areas recently reclaimed from the desert near Ismailia. Using data from free-listing and triadic comparisons, it is shown that schistosomiasis is primarily seen as a urinary disease. Factor analysis performed on a series of 12 questions on the symptoms of schistosomiasis included in a survey demonstrated that responses group into three patterns, the first stressing constitutional symptoms such as weakness, the second stressing abdominal symptoms and the third blood in the urine, burning on urination and blood in the stool. The paper discusses the implications of these findings for efforts to promote regular treatment with praziquantel of people living in or near the Nile Delta who are at risk for intestinal schistosomiasis.

  15. Assessing the influence of water level on schistosomiasis in Dongting Lake region before and after the construction of Three Gorges Dam.

    PubMed

    Li, Zhongwu; Nie, Xiaodong; Zhang, Yan; Huang, Jinquan; Huang, Bin; Zeng, Guangming

    2016-01-01

    Schistosomiasis is a severe public health problem in the Dongting Lake region, and its distribution, prevalence, and intensity of infection are particularly sensitive to environmental changes. In this study, the human and bovine schistosomiasis variations in the Dongting Lake region were studied from 1996 to 2010, and the relationships between schistosomiasis and water level were examined. Furthermore, based on these results, the potential effects of the Three Gorges Dam (TGD) on schistosomiasis were investigated. Results showed an increase in human schistosomiasis and in the scope of seriously affected regions, along with a decrease in bovine schistosomiasis. Human schistosomiasis was negatively correlated with water level during wet season (from May to October), particularly the average water level in October. This finding indicated that the decreasing water level may be highly related to the increasing of human schistosomiasis in the Dongting Lake region. Based on this result and the variation of schistosomiasis before and after the construction and operation of TGD, the impoundment of the Three Gorges reservoir is believed to decrease the water level and increase the contact between people and schistosomiasis. Therefore, the TGD, which is operated by regulating water and scheduling water operations, is not good for the control of human schistosomiasis in the Dongting Lake region. Although the extent of the influence of the TGD on schistosomiasis remains unclear, the influence of the TGD on preventing and controlling schistosomiasis should not be ignored.

  16. Schistosomiasis Breeding Environment Situation Analysis in Dongting Lake Area

    NASA Astrophysics Data System (ADS)

    Li, Chuanrong; Jia, Yuanyuan; Ma, Lingling; Liu, Zhaoyan; Qian, Yonggang

    2013-01-01

    Monitoring environmental characteristics, such as vegetation, soil moisture et al., of Oncomelania hupensis (O. hupensis)’ spatial/temporal distribution is of vital importance to the schistosomiasis prevention and control. In this study, the relationship between environmental factors derived from remotely sensed data and the density of O. hupensis was analyzed by a multiple linear regression model. Secondly, spatial analysis of the regression residual was investigated by the semi-variogram method. Thirdly, spatial analysis of the regression residual and the multiple linear regression model were both employed to estimate the spatial variation of O. hupensis density. Finally, the approach was used to monitor and predict the spatial and temporal variations of oncomelania of Dongting Lake region, China. And the areas of potential O. hupensis habitats were predicted and the influence of Three Gorges Dam (TGB)project on the density of O. hupensis was analyzed.

  17. Incremental Transductive Learning Approaches to Schistosomiasis Vector Classification

    NASA Astrophysics Data System (ADS)

    Fusco, Terence; Bi, Yaxin; Wang, Haiying; Browne, Fiona

    2016-08-01

    The key issues pertaining to collection of epidemic disease data for our analysis purposes are that it is a labour intensive, time consuming and expensive process resulting in availability of sparse sample data which we use to develop prediction models. To address this sparse data issue, we present the novel Incremental Transductive methods to circumvent the data collection process by applying previously acquired data to provide consistent, confidence-based labelling alternatives to field survey research. We investigated various reasoning approaches for semi-supervised machine learning including Bayesian models for labelling data. The results show that using the proposed methods, we can label instances of data with a class of vector density at a high level of confidence. By applying the Liberal and Strict Training Approaches, we provide a labelling and classification alternative to standalone algorithms. The methods in this paper are components in the process of reducing the proliferation of the Schistosomiasis disease and its effects.

  18. Parasitic procrastination: late-presenting ovale malaria and schistosomiasis.

    PubMed

    Davis, T M; Singh, B; Sheridan, G

    2001-08-06

    A 29-year-old woman with ovale malaria (most likely contracted, together with asymptomatic schistosomiasis, in East Africa two years previously) had fever, nausea and confusion, jaundice, anaemia, thrombocytopenia, hyponatraemia and hypokalaemia. She was initially diagnosed with and treated for blood-smear-positive vivax malaria. Because of the unusual clinical presentation, blood was analysed by a malaria species-specific nested polymerase chain reaction (PCR) assay which identified Plasmodium ovale as the only infecting species. This case illustrates (i) that a detailed travel history remains a vital part of clinical assessment, (ii) ovale malaria can have an exceptionally long incubation period and features of a moderately severe acute infection, and (iii) PCR assay may prove a valuable adjunct to blood film examination in the diagnosis and speciation of malaria.

  19. Comparative trials of antimonial drugs in urinary schistosomiasis

    PubMed Central

    Davis, A.

    1968-01-01

    Chemotherapeutic trials in urinary schistosomiasis are described and discussed. Their design and conduct were based on recommended statistical techniques, now generally accepted as the most appropriate approach to the assessment of antischistosomal drugs. Randomization produced comparable host groups in whom multiple parasitic infection and radiological urinary tract damage were common. Treatment was with one of three antimonial compounds given at equivalent metallic dosage daily. Antimony sodium tartrate (AST) and antimony dimercaptosuccinate (TWSb) were equally efficient curatively but both produced many side-effects. Sodium antimonylgluconate (TSAG) was four-fifths as effective but tolerance was superior. Estimations of urinary antimony excretion showed that tissue retention of the metal was related to cure-rates and side-effects. It was concluded that none of the drugs were suitable for mass chemotherapy. More new non-toxic schistosomicides are urgently needed and for their assessment, the setting-up of multicentre trials, following international agreement on technical methods, is suggested. PMID:5302298

  20. Higher Frequency of Circulating PD-1(high) CXCR5(+)CD4(+) Tfh Cells in Patients with Chronic Schistosomiasis.

    PubMed

    Zhang, Yumei; Jiang, Yanyan; Wang, Yanjuan; Liu, Hua; Shen, Yujuan; Yuan, Zhongying; Hu, Yuan; Xu, Yuxin; Cao, Jianping

    2015-01-01

    The current knowledge of immunological responses to schistosomiasis is insufficient for the development of vaccine and therapies. The role of T follicular helper (Tfh) cells in schistosome infections is not fully defined. The frequency of circulating Tfh cells and serum cytokine levels were analyzed in 11 patients with chronic schistosomiasis and 10 healthy controls (HC), who reside in an endemic area for Schistosomiasis japonicum. Significantly higher frequencies of circulating CXCR5(+) CD4(+) Tfh cells and higher expression levels of ICOS and PD-1 in CXCR5(+) CD4(+) Tfh cells were observed in patients with chronic schistosomiasis compared to HC. The levels of IL-21 in serum and the expression of IL-21 mRNA were higher in chronic schistosomiasis patients than in HC. Moreover, the frequency of circulating PD-1(high) CXCR5(+) CD4(+) Tfh cells positively correlated with the levels of IL-21 in serum from patients with chronic schistosomiasis. A positive correlation was also found between the frequency of PD-1(high) CXCR5(+) CD4(+) Tfh cells and the levels of soluble egg antigen (SEA)-specific antibodies in serum samples from the patient group. Our study is the first regarding Tfh cells in chronic human schistosomiasis and the finding indicate that PD-1(high) CXCR5(+) CD4(+)Tfh cells might play an important role in the production of specific antibodies in schistosomiasis. This study contributes to the understanding of immune response to schistosomiasis and may provide helpful support in vaccine development.

  1. Collaborative study on antigens for immunodiagnosis of schistosomiasis*

    PubMed Central

    Mott, K. E.; Dixon, H.

    1982-01-01

    Eight research laboratories in Europe and the United States of America were selected on the basis of having published data on Schistosoma mansoni and S. japonicum antigens to participate in a study of various antigen/test combinations for immunodiagnosis of schistosomiasis. The serum bank consisted of 395 well documented sera from four endemic areas in Brazil (2 areas), Kenya, and the Philippines. Altogether, 21 S. mansoni and four S. japonicum antigen and immunoassay combinations were evaluated. S. mansoni egg antigens yielded a higher combined sensitivity than adult worm antigens, irrespective of their purity, in active S. mansoni infections before and after specific treatment. Quantitative seroreactivity of characterized S. mansoni egg antigens showed good correlation with faecal egg counts in the 5-14 year age group. No correlation between morbidity related to S. mansoni and seroreactivity was observed in any test system. Three S. japonicum egg antigens showed high sensitivity and specificity in relation to the presence or absence of eggs in the stool. The quantitative seroreactivity of the characterized S. japonicum egg antigens correlated directly with the intensity of S. japonicum infection in all age groups. The enzyme-linked immunosorbent assay (ELISA), using several different procedures, performed well with the antigens used in the study. The indium slide immunoassay (ISI), a simple qualitative visual test system using an S. mansoni egg antigen, demonstrated a high degree of sensitivity and specificity. The results did not indicate the superiority of any particular immunodiagnostic method for detecting antischistosome antibodies. This collaborative study is considered a first step towards developing and standardizing antigens for immunodiagnosis of schistosomiasis. PMID:6983926

  2. Immunomodulatory effects of curcumin treatment on murine schistosomiasis mansoni.

    PubMed

    Allam, Gamal

    2009-01-01

    Curcumin is a polyphenol derived from the dietary spice turmeric. It has been shown to regulate numerous transcription factors, cytokines, adhesion molecules, and enzymes that have been linked to inflammation. In addition to inhibiting the growth of a variety of pathogens, curcumin has been shown to have nematocidal activity. The present study was designed to evaluate the schistosomicidal activity of curcumin in vivo as well as immunomodulation of granulomatous inflammation and liver pathology in acute schistosomiasis mansoni. Mice were infected each with 80 Schistosoma (S.) mansoni cercariae and injected intraperitoneally with curcumin at a total dose of 400mg/kg body weight. Curcumin was effective in reducing worm and tissue-egg burdens, hepatic granuloma volume and liver collagen content by 44.4%, 30.9%, 79%, and 38.6%, respectively. Curcumin treatment restored hepatic enzymes activities to the normal levels and enhanced catalase activity in the liver tissue of infected mice. Moreover, hepato-spleenomegaly and eosinophilia induced by S. mansoni infection were largely improved with curcumin treatment. Infected mice treated with curcumin showed low serum level of both interleukin (IL)-12 and tumor necrosis factor alpha (TNF-alpha), but IL-10 level was not significantly altered. Specific IgG and IgG1 responses against both soluble worm antigen (SWAP) and soluble egg antigen (SEA) were augmented with curcumin treatment, but IgM and IgG2a responses were not significantly changed. In conclusion, curcumin treatment modulates cellular and humoral immune responses of infected mice and lead to a significant reduction of parasite burden and liver pathology in acute murine schistosomiasis mansoni.

  3. Cysteine Peptidases as Schistosomiasis Vaccines with Inbuilt Adjuvanticity

    PubMed Central

    El Ridi, Rashika; Tallima, Hatem; Selim, Sahar; Donnelly, Sheila; Cotton, Sophie; Gonzales Santana, Bibiana; Dalton, John P.

    2014-01-01

    Schistosomiasis is caused by several worm species of the genus Schistosoma and afflicts up to 600 million people in 74 tropical and sub-tropical countries in the developing world. Present disease control depends on treatment with the only available drug praziquantel. No vaccine exists despite the intense search for molecular candidates and adjuvant formulations over the last three decades. Cysteine peptidases such as papain and Der p 1 are well known environmental allergens that sensitize the immune system driving potent Th2-responses. Recently, we showed that the administration of active papain to mice induced significant protection (P<0.02, 50%) against an experimental challenge infection with Schistosoma mansoni. Since schistosomes express and secrete papain-like cysteine peptidases we reasoned that these could be employed as vaccines with inbuilt adjuvanticity to protect against these parasites. Here we demonstrate that sub-cutaneous injection of functionally active S. mansoni cathepsin B1 (SmCB1), or a cathepsin L from a related parasite Fasciola hepatica (FhCL1), elicits highly significant (P<0.0001) protection (up to 73%) against an experimental challenge worm infection. Protection and reduction in worm egg burden were further increased (up to 83%) when the cysteine peptidases were combined with other S. mansoni vaccine candidates, glyceraldehyde 3-phosphate dehydrogenase (SG3PDH) and peroxiredoxin (PRX-MAP), without the need to add chemical adjuvants. These studies demonstrate the capacity of helminth cysteine peptidases to behave simultaneously as immunogens and adjuvants, and offer an innovative approach towards developing schistosomiasis vaccines PMID:24465551

  4. Protective Potential of Antioxidant Enzymes as Vaccines for Schistosomiasis in a Non-Human Primate Model

    PubMed Central

    Carvalho-Queiroz, Claudia; Nyakundi, Ruth; Ogongo, Paul; Rikoi, Hitler; Egilmez, Nejat K.; Farah, Idle O.; Kariuki, Thomas M.; LoVerde, Philip T.

    2015-01-01

    Schistosomiasis remains a major cause of morbidity in the world. The challenge today is not so much in the clinical management of individual patients, but rather in population-based control of transmission in endemic areas. Despite recent large-scale efforts, such as integrated control programs aimed at limiting schistosomiasis by improving education and sanitation, molluscicide treatment programs and chemotherapy with praziquantel, there has only been limited success. There is an urgent need for complementary approaches, such as vaccines. We demonstrated previously that anti-oxidant enzymes, such as Cu–Zn superoxide dismutase (SOD) and glutathione S peroxidase (GPX), when administered as DNA-based vaccines induced significant levels of protection in inbred mice, greater than the target 40% reduction in worm burden compared to controls set as a minimum by the WHO. These results led us to investigate if immunization of non-human primates with antioxidants would stimulate an immune response that could confer protection as a prelude study for human trials. Issues of vaccine toxicity and safety that were difficult to address in mice were also investigated. All baboons in the study were examined clinically throughout the study and no adverse reactions occurred to the immunization. When our outbred baboons were vaccinated with two different formulations of SOD (SmCT-SOD and SmEC-SOD) or one of GPX (SmGPX), they showed a reduction in worm number to varying degrees, when compared with the control group. More pronounced, vaccinated animals showed decreased bloody diarrhea, days of diarrhea, and egg excretion (transmission), as well as reduction of eggs in the liver tissue and in the large intestine (pathology) compared to controls. Specific IgG antibodies were present in sera after immunizations and 10 weeks after challenge infection compared to controls. Peripheral blood mononuclear cells, mesenteric, and inguinal node cells from vaccinated animals proliferated and

  5. [Epidemics of schistosomiasis in military staff assigned to endemic areas: standard diagnostic techniques and the development of real-time PCR techniques].

    PubMed

    Biance-Valero, E; De Laval, F; Delerue, M; Savini, H; Cheinin, S; Leroy, P; Soullié, B

    2013-05-01

    The authors report the results of molecular biology techniques for the early diagnosis of cases (invasion phase) of schistosomiasis during two epidemics occurring during French military projects in the Central African Republic and Madagascar. The use of these techniques in real time for subjects not residing in the endemic area significantly improves the sensitivity of screening. The attack rates of these episodes, according to a case definition that took positive specific PCR results into account, were 59% and 26%. These results are a concrete illustration of the proverb that "yaws begin where the trail stops".

  6. "Naturally occurring asbestos

    NASA Astrophysics Data System (ADS)

    Cagnard, F.; Lahondère, D.; Blein, O.; Lahfid, A.; Wille, G.

    2012-04-01

    The term asbestos refers to six silicate minerals from amphibole and serpentine groups. By definition, it consists in bundles of thin and flexible long fibers, with high-tensile strength, and chemical and heat resistance. In contrast to asbestos found within commercial products and mining, the specific term ''naturally occurring asbestos'' (NOA) refers to asbestiform minerals occurring within rocks or soils that can be released by human activities or weathering processes. The fact that the exposure to asbestos is related to lung pathologies is now widely demonstrated (e.g. asbestosis, mesothelioma and lung cancer). However, if health risks associated with exposure to NOA exist, they are not yet well documented. The crystallization of natural asbestos occurs in specific Mg-rich lithologies associated with peculiar structural and metamorphic conditions. By recognizing and combining such specific geologic criteria, the presence or the absence of asbestos in bedrock terrains can be reasonably predicted and maps of NOA hazard can be drawn. We present here new results of geological mapping and petrological study concerning the evaluation of the NOA hazard in the Alps and Corsica, in France. The three folds approach consists in (1) a determination of lithologies with potential NOA from a bibliographic compilation and extraction of target zones from a geological geodatabase (2) a geological mapping of the target zones followed by a petrological characterization of sampled asbestiform minerals in the laboratory (optical microscopy, TEM, SEM, and Raman spectroscopy technics), and (3) the drawing of the final map of NOA hazard, at regional-scale. Occurrence criteria can be retained as follows: 1. NOA are abundant in the internal zones of the Alps and Corsica, especially within ophiolitic complexes. Natural asbestos are mostly concentrated within ultramafic rocks but can also occur within basic lithologies such as Mg-metagabbros, metabasalts and meta-pillow-lavas, 2. Asbestos

  7. Building a global schistosomiasis alliance: an opportunity to join forces to fight inequality and rural poverty.

    PubMed

    Savioli, Lorenzo; Albonico, Marco; Colley, Daniel G; Correa-Oliveira, Rodrigo; Fenwick, Alan; Green, Will; Kabatereine, Narcis; Kabore, Achille; Katz, Naftale; Klohe, Katharina; LoVerde, Philip T; Rollinson, David; Stothard, J Russell; Tchuem Tchuenté, Louis-Albert; Waltz, Johannes; Zhou, Xiao-Nong

    2017-03-23

    Schistosomiasis, one of the 17 neglected tropical diseases listed by the World Health Organization, presents a substantial public health and economic burden. Of the 261 million people requiring preventive chemotherapy for schistosomiasis in 2013, 92% of them lived in sub-Saharan Africa and only 12.7% received preventive chemotherapy. Moreover, in 2010, the WHO reported that schistosomiasis mortality could be as high as 280 000 per year in Africa alone.In May 2012 delegates to the sixty-fifth World Health Assembly adopted resolution WHA65.21 that called for the elimination of schistosomiasis, and foresees the regular treatment of at least 75% of school age children in at-risk areas. The resolution urged member states to intensify schistosomiasis control programmes and to initiate elimination campaigns where possible.Despite this, in June 2015, schistosomiasis was indicated to have the lowest level of preventive chemotherapy implementation in the spectrum of neglected tropical diseases. It was also highlighted as the disease most lacking in progress. This is perhaps unsurprising, given that it was also the only NTD with access to drug donations but without a coalition of stakeholders that collaborates to boost commitment and implementation.As a consequence, and to ensure that the WHO NTDs Roadmap Targets of 2012 and World Health Assembly Resolution WHA65.21 are met, the Global Schistosomiasis Alliance (GSA) has been set up. Diverse and representative, the GSA aims to be a partnership of endemic countries, academic and research institutions, international development agencies and foundations, international organizations, non-governmental development organizations, private sector companies and advocacy and resource mobilisation partners. Ultimately, the GSA calls for a partnership to work for the benefit of endemic countries by addressing health inequity and rural poverty.

  8. Participatory action research: community diagnosis and intervention in controlling urinary schistosomiasis in an urban community in Ibadan, Nigeria.

    PubMed

    Olaseha, I O; Sridhar, M K C

    Schistosomiasis is second only to malaria and is endemic in Nigeria. It has been reported that the infection is more prevalent, irrespective of gender, in the age group 5 to 14 years. It is least among the age group 26 and 55 and occurs mostly in the rural areas in the country. The infection is spreading from the rural areas to various urban communities, particularly the agricultural and fishing populations. In Ibadan, capital of Oyo State in southwestern Nigeria where the focus of this study is made, the infection has been reported among children and adolescents in six Local Government Areas. Students of Advanced Diploma in Health Education (ADHE) of the Department of Health Promotion and Education, during a community diagnosis exercise among primary schools in two communities in Ibadan, met with this problem. The purpose of this study is to mobilize the affected communities, with both internal and external resources through a participatory-action process, to combat the infection which is one of their major problems. Since the providence of schistosomiasis in target communities is age related, investigations were concentrated in 17 Primary Schools in the two communities. The investigation involved laboratory confirmation by collecting 147 urine samples from a total population of 676 children and examining them microscopically for the schistosoma ova. In addition, the quality of stream water and their vector presence were assessed. The key intervention strategy used was community mobilization of both internal and external resources of targeted communities. The striking outcome of the intervention study is that the outbreak of schistosomiasis in the communities was formally reported to the Federal Ministry of Health and the Oyo State Ministry of Health. All infected pupils were treated, the long awaited water scheme to replace the broken pipes was completed, and two new water supply schemes were implemented by the communities. Further, the communities displayed sign

  9. Factors influencing community participation in control and related operational research for urogenital schistosomiasis and soil-transmitted helminths in rural villages of Kwale County, coastal Kenya

    PubMed Central

    Macharia, Jacinta Wairimu; Ng'ang'a, Zipporah W; Njenga, Sammy Michugu

    2016-01-01

    Introduction helminthic infections caused by soil-transmitted helminths (STH) and schistosomes are among the most prevalent afflictions of humans who live in areas of poverty. An operational research was undertaken in 5 villages of Kwale County during a pilot control programme which included both the adults and school going children. Willingness of community members to participate in the treatment as well as in the research is critical. A cross sectional study sought to determine factors influencing community participation in control and related operational research and assess the treatment coverage for urogenital schistosomiasis and hookworms in rural villages of Kwale County. Methods cross-sectional survey utilized quantitative and qualitative methods of data collection. A total of 220 households were recruited and household heads interviewed. Bivariate analysis was used to test association between different independent and dependent factors. Multivariate analysis was done using binary logistic regression to control for confounders and effect modification. Qualitative data was transcribed, coded and analyzed thematically. Results religion and levels of income were significantly (P =0.04 and P = 0.026 respectively) associated with participation in the research and control programme, history of ever suffering from schistosomiasis and intestinal worms was found to be significantly (P = 0.008) associated with participation in the research. The study established that 82% (178) of the respondents received treatment for urogenital schistosomiasis and hookworms and 67% (146) of the respondents had participated in the research. Conclusion this information will be useful in promoting health, enhancing learning and behaviour changes which will lead to increased community participation in similar disease control. PMID:27642474

  10. Naturally occurring insecticides.

    PubMed Central

    Soloway, S B

    1976-01-01

    Naturally occurring insecticides are abundant and varied in their effects, though but a few are articles of commerce. Even for these, pyrethrum, nicotine, rotenone, hellebore, ryania, and sabadilla, there is a paucity of information on mammalian toxicology and environmental effects. In general, these materials are characterized favorably by low acute toxicity and ready dissipation in nature. Unfavorable aspects of natural insecticides are the contained mixture of active and inactive components and the low active ingredient content on a crop yield basis pointing to a high unit cost. Natural insecticides can serve additionally as leads to unnatural mimics, of which the commercially successful synthetic pyrethroids are prime examples. The chemical nature, relationship of insecticidal activity to chemical structure, occurrence, production, and utilization, registered uses, metabolism, and insect and mammalian toxicity are reviewed. PMID:789058

  11. A Rapid Monitoring and Evaluation Method of Schistosomiasis Based on Spatial Information Technology.

    PubMed

    Wang, Yong; Zhuang, Dafang

    2015-12-12

    Thanks to Spatial Information Technologies (SITs) such as Remote Sensing (RS) and Geographical Information System (GIS) that are being quickly developed and updated, SITs are being used more widely in the public health field. The use of SITs to study the characteristics of the temporal and spatial distribution of Schistosoma japonicum and to assess the risk of infection provides methods for the control and prevention of schistosomiasis japonica has gradually become a hot topic in the field. The purpose of the present paper was to use RS and GIS technology to develop an efficient method of prediction and assessment of the risk of schistosomiasis japonica. We choose the Yueyang region, close to the east DongTing Lake (Hunan Province, China), as the study area, where a recent serious outbreak of schistosomiasis japonica took place. We monitored and evaluated the transmission risk of schistosomiasis japonica in the region using SITs. Water distribution data were extracted from RS images. The ground temperature, ground humidity and vegetation index were calculated based on RS images. Additionally, the density of oncomelania snails, which are the Schistosoma japonicum intermediate host, was calculated on the base of RS data and field measurements. The spatial distribution of oncomelania snails was explored using SITs in order to estimate the area surrounding the residents with transmission risk of schistosomiasis japonica. Our research result demonstrated: (1) the risk factors for the transmission of schistosomiasis japonica were closely related to the living environment of oncomelania snails. Key factors such as water distribution, ground temperature, ground humidity and vegetation index can be quickly obtained and calculated from RS images; (2) using GIS technology and a RS deduction technique along with statistical regression models, the density distribution model of oncomelania snails could be quickly built; (3) using SITs and analysis with overlaying population

  12. A Rapid Monitoring and Evaluation Method of Schistosomiasis Based on Spatial Information Technology

    PubMed Central

    Wang, Yong; Zhuang, Dafang

    2015-01-01

    Thanks to Spatial Information Technologies (SITs) such as Remote Sensing (RS) and Geographical Information System (GIS) that are being quickly developed and updated, SITs are being used more widely in the public health field. The use of SITs to study the characteristics of the temporal and spatial distribution of Schistosoma japonicum and to assess the risk of infection provides methods for the control and prevention of schistosomiasis japonica has gradually become a hot topic in the field. The purpose of the present paper was to use RS and GIS technology to develop an efficient method of prediction and assessment of the risk of schistosomiasis japonica. We choose the Yueyang region, close to the east DongTing Lake (Hunan Province, China), as the study area, where a recent serious outbreak of schistosomiasis japonica took place. We monitored and evaluated the transmission risk of schistosomiasis japonica in the region using SITs. Water distribution data were extracted from RS images. The ground temperature, ground humidity and vegetation index were calculated based on RS images. Additionally, the density of oncomelania snails, which are the Schistosoma japonicum intermediate host, was calculated on the base of RS data and field measurements. The spatial distribution of oncomelania snails was explored using SITs in order to estimate the area surrounding the residents with transmission risk of schistosomiasis japonica. Our research result demonstrated: (1) the risk factors for the transmission of schistosomiasis japonica were closely related to the living environment of oncomelania snails. Key factors such as water distribution, ground temperature, ground humidity and vegetation index can be quickly obtained and calculated from RS images; (2) using GIS technology and a RS deduction technique along with statistical regression models, the density distribution model of oncomelania snails could be quickly built; (3) using SITs and analysis with overlaying population

  13. The schistosomiasis problem in the world: results of a WHO questionnaire survey

    PubMed Central

    Iarotski, L. S.; Davis, A.

    1981-01-01

    This article presents an overview of the magnitude of the schistosomiasis problem throughout the world, and is based on information on schistosomiasis control programmes provided by 103 countries in reply to a questionnaire circulated by the World Health Organization in 1976. According to the data either given in these replies, published, or provided in internal reports to WHO, schistosomiasis is one of the most widespread parasitic infections of man. Some 500 million people are thought to be exposed to infection and four main species of schistosomes are prevalent, together with their various intermediate snail hosts, in 73 countries. Control programmes are operating in 41% of responding endemic countries although they are on a national scale only in Brazil, Dominican Republic, Egypt, Iran, Iraq, Japan, Morocco, Puerto Rico, St Lucia, Tunisia, and Venezuela. It appears that a maximum of only 1-2% of all cases have been treated, the most frequently used drugs being niridazole and hycanthone. A small number of efficient molluscicides are in regular use but their high cost precludes large-scale application. Installation of water supplies and health education are the most frequently used non-specific control measures. Nearly 50% of endemic countries use more than three different methods of control simultaneously. The national schistosomiasis control programmes in Brazil, Egypt, Iran, Japan, Puerto Rico, and Venezuela are examples of combined approaches that have resulted in a significant decline in the prevalence of schistosomiasis. Finally, some specific needs in research, control, and training of personnel are discussed. PMID:6973414

  14. Schistosomiasis Sustained Control Program in Ethnic Groups Around Ninefescha (Eastern Senegal).

    PubMed

    N'Diaye, Monique; Dioukhane, Elhadji M; Ndao, Babacar; Diedhiou, Kemo; Diawara, Lamine; Talla, Idrissa; Vernet, Charlotte; Bessin, François; Barbier, Dominique; Dewavrin, Patrick; Klotz, Francis; Georges, Pierre

    2016-09-07

    Schistosomiasis is the second most significant parasitic disease in children in several African countries. For this purpose, the "Programme National de Lutte contre les Bilharzioses" (PNLB) was developed in partnership with the World Health Organization (WHO) to control this disease in Senegal. However, geographic isolation of Bedik ethnic groups challenged implementation of the key elements of the schistosomiasis program in eastern Senegal, and therefore, a hospital was established in Ninefescha to improve access to health care as well as laboratory support for this population. The program we have implemented from 2008 in partnership with the PNLB/WHO involved campaigns to 1) evaluate schistosomiasis prevalence in children of 53 villages around Ninefescha hospital, 2) perform a mass drug administration following the protocol established by the PNLB in school-aged children, 3) monitor annual prevalence, 4) implement health education campaigns, and 5) oversee the building of latrines. This campaign led to a drop in schistosomiasis prevalence but highlighted that sustainable schistosomiasis control by praziquantel treatment, awareness of the use of latrines, and inhabitants' voluntary commitment to the program are crucial to improve Schistosoma elimination. Moreover, this study revealed that preschool-aged children, for whom praziquantel was not recommended until 2014 in Senegal, constituted a significant reservoir for the parasite.

  15. Apropos: critical analysis of molluscicide application in schistosomiasis control programs in Brazil.

    PubMed

    Li, Hongjun; Wang, Wei

    2017-03-07

    Schistosomiasis is a snail-transmitted infectious disease affecting over 200 million people worldwide. Snail control has been recognized as an effective approach to interrupt the transmission of schistosomiasis, since the geographic distribution of this neglected tropical disease is determined by the presence of the intermediate host snails. In a recent Scoping Review published in Infectious Diseases of Poverty, Coelho and Caldeira performed a critical review of using molluscicides in the national schistosomiasis control programs in Brazil. They also described some chemical and plant-derived molluscicides used in China. In addition to the molluscicides described by Coelho and Caldeira, a large number of chemicals, plant extracts and microorganisms have been screened and tested for molluscicidal actions against Oncomelania hupensis, the intermediate host of Schistosoma japonicum in China. Here, we presented the currently commercial molluscicides available in China, including 26% suspension concentrate of metaldehyde and niclosamide (MNSC), 25% suspension concentrate of niclosamide ethanolamine salt (SCNE), 50% niclosamide ethanolamine salt wettable powder (WPN), 4% niclosamide ethanolamine salt dustable powder (NESP), 5% niclosamide ethanolamine salt granule (NESG) and the plant-derived molluscicide "Luowei". These molluscicides have been proved to be active against O. hupensis in both laboratory and endemic fields, playing an important role in the national schistosomiasis control program of China. Currently, China is transferring its successful experiences on schistosomiasis control to African countries. The introduction of Chinese commercial molluscicides to Africa, with adaptation to local conditions, may facilitate the progress towards the elimination of schisosomiasis in Africa.

  16. Critical analysis of molluscicide application in schistosomiasis control programs in Brazil.

    PubMed

    Coelho, Pmz; Caldeira, R L

    2016-07-04

    In Brazil, Biomphalaria glabrata, B. tenagophila, and B. straminea are naturally infected by the trematode Schistosoma mansoni, the causative agent of schistosomiasis. Despite decades of governmental efforts through official control programs, schistosomiasis remains an important public health problem in the country: thousands of people are infected with the trematode each year and millions live in endemic areas. The World Health Organization recommends using a combination of molluscicide (niclosamide) and mass chemotherapy to control the transmission of schistosomiasis, with this treatment successfully reducing the morbidity of the disease. In the past, niclosamide has been used in official schistosomiasis control programs in Brazil. However, as B. glabrata recolonizes even after molluscicide application, the use of molluscicides has gradually decreased in the country until they were discontinued in 2002, mainly due to the rising global pressure to preserve the environment and the difficulties of obtaining licenses from the Brazilian Ministry of Environment to use toxic substances in aquatic ecosystems. Therefore, the discovery of new molluscicides, which could be more selective to Biomphalaria species and less harmful to the aquatic ecosystem, is necessary. In addition, political efforts to sensitize funders to provide grants for this field of research are required. In this context, this article aims to make a critical analysis of molluscicide application in schistosomiasis control programs in Brazil.

  17. PREVALENCE AND RISK FACTORS OF SCHISTOSOMIASIS AMONG HAUSA COMMUNITIES IN KANO STATE, NIGERIA

    PubMed Central

    DAWAKI, Salwa; AL-MEKHLAFI, Hesham Mahyoub; ITHOI, Init; IBRAHIM, Jamaiah; ABDULSALAM, Awatif Mohammed; AHMED, Abdulhamid; SADY, Hany; ATROOSH, Wahib Mohammed; AL-AREEQI, Mona Abdullah; ELYANA, Fatin Nur; NASR, Nabil Ahmed; SURIN, Johari

    2016-01-01

    SUMMARY Schistosomiasis remains one of the most prevalent neglected tropical diseases especially in Nigeria which has the greatest number of infected people worldwide. A cross-sectional study was conducted among 551 participants from Kano State, North Central Nigeria. Fecal samples were examined for the presence of Schistosoma mansoni eggs using the formalin-ether sedimentation method while the urine samples were examined using the filtration technique for the presence of S. haematobium eggs. Demographic, socioeconomic and environmental information was collected using a pre-validated questionnaire. The overall prevalence of schistosomiasis was 17.8%, with 8.9% and 8.3% infected with S. mansoni and S. haematobium, respectively and 0.5% presenting co-infection with both species. The multiple logistic regression analysis revealed that age < 18 years (OR = 2.13; 95% CI; 1.34- 3.41), presence of infected family members (OR = 3.98; 95% CI; 2.13-7.46), and history of infection (OR = 2.87; 95% CI; 1.87- 4.56) were the significant risk factors associated with schistosomiasis in these communities. In conclusion, this study revealed that schistosomiasis is still prevalent among Hausa communities in Nigeria. Mass drug administration, health education and community mobilization are imperative strategies to significantly reduce the prevalence and morbidity of schistosomiasis in these communities. PMID:27410914

  18. Use of circulating cathodic antigen (CCA) dipsticks for detection of intestinal and urinary schistosomiasis.

    PubMed

    Stothard, J Russell; Kabatereine, Narcis B; Tukahebwa, Edridah M; Kazibwe, Francis; Rollinson, David; Mathieson, William; Webster, Joanne P; Fenwick, Alan

    2006-02-01

    An evaluation of a commercially available antigen capture dipstick that detects schistosome circulating cathodic antigen (CCA) in urine was conducted in representative endemic areas for intestinal and urinary schistosomiasis in Uganda and Zanzibar, respectively. Under field-based conditions, the sensitivity (SS) and specificity (SP) of the dipstick was 83 and 81% for detection of Schistosoma mansoni infections while positive predictive (PPV) and negative predictive values (NPV) were 84%. Light egg-positive infections were sometimes CCA-negative while CCA-positives included egg-negative children. A positive association between faecal egg output and intensity of CCA test band was observed. Estimating prevalence of intestinal schistosomiasis by school with dipsticks was highly correlated (r=0.95) with Kato-Katz stool examinations, typically within +/-8.5%. In Zanzibar, however, dipsticks totally failed to detect S. haematobium despite examining children with egg-patent schistosomiasis. This was also later corroborated by further surveys in Niger and Burkina Faso. Laboratory testing of dipsticks with aqueous adult worm lysates from several reference species showed correct functioning, however, dipsticks failed to detect CCA in urine from S. haematobium-infected hamsters. While CCA dipsticks are a good alternative, or complement, to stool microscopy for field diagnosis of intestinal schistosomiasis, they have no proven value for field diagnosis of urinary schistosomiasis. At approximately 2.6 US dollars per dipstick, they are presently too expensive to be cost-effective for wide scale use in disease mapping surveys unless Lot Quality Assurance Sampling (LQAS) strategies are developed.

  19. Are Independent Probes Truly Independent?

    ERIC Educational Resources Information Center

    Camp, Gino; Pecher, Diane; Schmidt, Henk G.; Zeelenberg, Rene

    2009-01-01

    The independent cue technique has been developed to test traditional interference theories against inhibition theories of forgetting. In the present study, the authors tested the critical criterion for the independence of independent cues: Studied cues not presented during test (and unrelated to test cues) should not contribute to the retrieval…

  20. Naturally Occurring Food Toxins

    PubMed Central

    Dolan, Laurie C.; Matulka, Ray A.; Burdock, George A.

    2010-01-01

    Although many foods contain toxins as a naturally-occurring constituent or, are formed as the result of handling or processing, the incidence of adverse reactions to food is relatively low. The low incidence of adverse effects is the result of some pragmatic solutions by the US Food and Drug Administration (FDA) and other regulatory agencies through the creative use of specifications, action levels, tolerances, warning labels and prohibitions. Manufacturers have also played a role by setting limits on certain substances and developing mitigation procedures for process-induced toxins. Regardless of measures taken by regulators and food producers to protect consumers from natural food toxins, consumption of small levels of these materials is unavoidable. Although the risk for toxicity due to consumption of food toxins is fairly low, there is always the possibility of toxicity due to contamination, overconsumption, allergy or an unpredictable idiosyncratic response. The purpose of this review is to provide a toxicological and regulatory overview of some of the toxins present in some commonly consumed foods, and where possible, discuss the steps that have been taken to reduce consumer exposure, many of which are possible because of the unique process of food regulation in the United States. PMID:22069686

  1. The epidemiology of human and animal schistosomiasis in the Senegal River Basin.

    PubMed

    Vercruysse, J; Southgate, V R; Rollinson, D

    1985-09-01

    The results of four field surveys in Senegal are reported. 1. A snail survey in various parts of the Senegal River Basin, including the Senegal River, temporary rain-fed pools, swamps, irrigation canals and drains, ricefields and Lac de Guier was carried out. Three species of snails were commonly found: Bulinus guernei was the most common, occurring in permanent habitats, Bulinus senegalensis occurring in laterite pools in the eastern part of the Middle Valley, and also in the ricefields of Guédé Chantier and Lampsar; B. forskalii was found in small numbers in Lac de Guier and Richard Toll. Three B. guernei were found to be naturally infected with S. bovis. Neither B. jousseaumei, B. globosus nor B. umbilicatus were found in our surveys. 2. A survey for urinary schistosomiasis was carried out in 100 villages (walo, near the Senegal River) and 11 villages (diéré, away from the river) by delivering questionnaires in schools and by direct examinations of haematuria samples. The prevalence of haematuria varied between 0 and 33%. Generally, walos showed low rates of haematuria with the exception of Lampsar and Guédé Chantier, and diérés showed higher rates of haematuria. 3. Examination of 400 cattle at the abattoir St. Louis, revealed a prevalence of 80% of schistosome infection. Two species were present, S. bovis and less commonly S. curassoni. Sometimes high worm burdens were seen, but lesions appeared to be minimal because of high ratio of male to female worms. 4. Examinations of 5722 sheep and 1752 goats in the abattoir, Dakar revealed an overall prevalence of 2.1%. Of the infected animals, 97.3% were infected with S. curassoni and 2.7% with S. curasonni and S. bovis. Laboratory snail infection experiments showed that S. curassoni is marginally compatible with B. senegalensis, but incompatible with B. guernei.

  2. The epidemiology of schistosomiasis mansoni and soil-transmitted helminths in elementary school children from the South Gondar Zone of the Amhara National Regional State, Ethiopia.

    PubMed

    Jemaneh, L

    2000-04-01

    In a cross-sectional survey undertaken in 22 communities of 6 districts in the South Gondar Zone of the Amhara National Regional State, 2279 school children had their stools examined for schistosomiasis mansoni and soil-transmitted helminths using the Kato-Katz technique. Overall the prevalence rates were 16.4%, 28.9%, 9.5% and 12.9% for S. mansoni, A. lumbricoides, T. trichiura and the hookworms, respectively. S. mansoni infection was registered from 14 of the 22 communities, in more than 60% of which the prevalence was over 20%. Infection with A. lumbricoides was noted in 20 schools and except in three schools the prevalence was above 20%. T. trichiura infection was found in 19 of the 22 schools with prevalence rates from 1.7% to 20.0%. Infection due to the hookworms was recorded in 17 schools, in 40% of which the prevalence was 20% or more. Generally communities of the western districts of the zone had higher infection rates of schistosomiasis mansoni and soil-transmitted helminthiasis as compared to those in the eastern districts. The presence of S. mansoni foci in 9 communities is reported for the first time. In general neither sex nor age were related to prevalence or intensity of infection. Forty nine percent of the examined children had one or more types of helminths, of which 32.5%, 13.3% and 2.4% were single, double and triple infections, respectively. A. lumbricoides commonly occurred with the other helminths. Multiplicity of infection was not sex related. 14.6%, 28.4%, 8.3% and 12.1% of the children had moderate or heavy infections of schistosomiasis mansoni, ascariasis, trichuriasis and hookworms, respectively.

  3. The Prawn Macrobrachium vollenhovenii in the Senegal River Basin: Towards Sustainable Restocking of All-Male Populations for Biological Control of Schistosomiasis

    PubMed Central

    Savaya Alkalay, Amit; Rosen, Ohad; Sokolow, Susanne H.; Faye, Yacinthe P. W.; Faye, Djibril S.; Aflalo, Eliahu D.; Jouanard, Nicolas; Zilberg, Dina; Huttinger, Elizabeth; Sagi, Amir

    2014-01-01

    Early malacological literature suggests that the outbreak of schistosomiasis, a parasitic disease transmitted by aquatic snails, in the Senegal River basin occurred due to ecological changes resulting from the construction of the Diama dam. The common treatment, the drug praziquantel, does not protect from the high risk of re-infection due to human contact with infested water on a daily basis. The construction of the dam interfered with the life cycle of the prawn Macrobrachium vollenhovenii by blocking its access to breeding grounds in the estuary. These prawns were demonstrated to be potential biological control agents, being effective predators of Schistosoma-susceptible snails. Here, we propose a responsible restocking strategy using all-male prawn populations which could provide sustainable disease control. Male prawns reach a larger size and have a lower tendency to migrate than females. We, therefore, expect that periodic restocking of all-male juveniles will decrease the prevalence of schistosomiasis and increase villagers' welfare. In this interdisciplinary study, we examined current prawn abundance along the river basin, complemented with a retrospective questionnaire completed by local fishermen. We revealed the current absence of prawns upriver and thus demonstrated the need for restocking. Since male prawns are suggested to be preferable for bio-control, we laid the molecular foundation for production of all-male M. vollenhovenii through a complete sequencing of the insulin-like androgenic gland-encoding gene (IAG), which is responsible for sexual differentiation in crustaceans. We also conducted bioinformatics and immunohistochemistry analyses to demonstrate the similarity of this sequence to the IAG of another Macrobrachium species in which neo-females are produced and their progeny are 100% males. At least 100 million people at risk of schistosomiasis are residents of areas that experienced water management manipulations. Our suggested non

  4. The temporal patterns of disease severity and prevalence in schistosomiasis

    SciTech Connect

    Ciddio, Manuela; Gatto, Marino Casagrandi, Renato

    2015-03-15

    Schistosomiasis is one of the most widespread public health problems in the world. In this work, we introduce an eco-epidemiological model for its transmission and dynamics with the purpose of explaining both intra- and inter-annual fluctuations of disease severity and prevalence. The model takes the form of a system of nonlinear differential equations that incorporate biological complexity associated with schistosome's life cycle, including a prepatent period in snails (i.e., the time between initial infection and onset of infectiousness). Nonlinear analysis is used to explore the parametric conditions that produce different temporal patterns (stationary, endemic, periodic, and chaotic). For the time-invariant model, we identify a transcritical and a Hopf bifurcation in the space of the human and snail infection parameters. The first corresponds to the occurrence of an endemic equilibrium, while the latter marks the transition to interannual periodic oscillations. We then investigate a more realistic time-varying model in which fertility of the intermediate host population is assumed to seasonally vary. We show that seasonality can give rise to a cascade of period-doubling bifurcations leading to chaos for larger, though realistic, values of the amplitude of the seasonal variation of fertility.

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

    PubMed

    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.

  6. Molluscicide for the control of schistosomiasis in irrigation schemes

    PubMed Central

    Shiff, C. J.; Clarke, V. de V.; Evans, A. C.; Barnish, G.

    1973-01-01

    The development of large areas of irrigation farming in the south-eastern lowveld of Southern Rhodesia has produced the risk of severe transmission of schistosomiasis over an extent of some 30 000 ha. Control measures instituted by the Ministry of Health were primarily directed against the large and widely distributed snail populations by using molluscicides. The chemical was applied to the irrigation water by drip-feed methods once every 6-8 months. The drains, however, were treated routinely by pairs of rangers searching for snails and applying chemical where they were found. The efficacy of control operations has been assessed by longitudinal studies in children free from infection to determine the incidence of infection. The results indicate that transmission of both Schistosoma haematobium and S. mansoni has been reduced to a level below that measured in areas of the country where irrigation is not practised. The total annual cost for this work was US$ 54 800-55 500. PMID:4542798

  7. The temporal patterns of disease severity and prevalence in schistosomiasis

    NASA Astrophysics Data System (ADS)

    Ciddio, Manuela; Mari, Lorenzo; Gatto, Marino; Rinaldo, Andrea; Casagrandi, Renato

    2015-03-01

    Schistosomiasis is one of the most widespread public health problems in the world. In this work, we introduce an eco-epidemiological model for its transmission and dynamics with the purpose of explaining both intra- and inter-annual fluctuations of disease severity and prevalence. The model takes the form of a system of nonlinear differential equations that incorporate biological complexity associated with schistosome's life cycle, including a prepatent period in snails (i.e., the time between initial infection and onset of infectiousness). Nonlinear analysis is used to explore the parametric conditions that produce different temporal patterns (stationary, endemic, periodic, and chaotic). For the time-invariant model, we identify a transcritical and a Hopf bifurcation in the space of the human and snail infection parameters. The first corresponds to the occurrence of an endemic equilibrium, while the latter marks the transition to interannual periodic oscillations. We then investigate a more realistic time-varying model in which fertility of the intermediate host population is assumed to seasonally vary. We show that seasonality can give rise to a cascade of period-doubling bifurcations leading to chaos for larger, though realistic, values of the amplitude of the seasonal variation of fertility.

  8. Schistosomiasis and Human Immunodeficiency Virus in Men in Tanzania.

    PubMed

    Downs, Jennifer A; de Dood, Claudia J; Dee, Hannah E; McGeehan, Megan; Khan, Hijab; Marenga, Abena; Adel, Patrick E; Faustine, Edward; Issarow, Benson; Kisanga, Emmanuel F; Kisigo, Godfrey Alfred; Ngahyolerwa, Salvius; Zahoro, Frank; Miyaye, Donald; Magawa, Ruth Gideon; Mngara, Julius; Lee, Myung Hee; Corstjens, Paul L A M; van Dam, Govert J; Fitzgerald, Daniel W

    2017-02-06

    Schistosomiasis is a parasitic worm infection that affects over 260 million individuals worldwide. Women with schistosome infections have been demonstrated to have a 4-fold increase in the odds of human immunodeficiency virus (HIV) infection compared with women without schistosome infections. A relationship between schistosome and HIV infections has not been clearly defined in men. Among 674 men aged 18-50 years living in rural Tanzania, we identified 429 (63.6%) who had a schistosome infection as defined by serum positivity for schistosome circulating anodic antigen, visualization of parasite eggs in urine or stool, or both. HIV infection was identified in 38 (5.6%). The odds of HIV infection was 1.3 [95% confidence interval = 0.6-2.5] (P = 0.53) among men with any schistosome infection (Schistosoma haematobium or Schistosoma mansoni), and it was 1.4 [0.6-3.3] (P = 0.43) among men with S. haematobium infection. Men with S. haematobium infection were significantly more likely to report the symptom of hemospermia than men without S. haematobium infection. We conclude that schistosome infections appear to have little to no association with HIV infection in men.

  9. Susceptibility or resistance of praziquantel in human schistosomiasis: a review.

    PubMed

    Wang, Wei; Wang, Li; Liang, You-Sheng

    2012-11-01

    Since praziquantel was developed in 1970s, it has replaced other antischistosomal drugs to become the only drug of choice for treatment of human schistosomiases, due to high efficacy, excellent tolerability, few and transient side effects, simple administration, and competitive cost. Praziquantel-based chemotherapy has been involved in the global control strategy of the disease and led to the control strategy shifting from disease control to morbidity control, which has greatly reduced the prevalence and intensity of infections. Given that the drug has been widely used for morbidity control in endemic areas for more than three decades, the emergence of resistance of Schistosoma to praziquantel under drug selection pressure has been paid much attention. It is possible to induce resistance of Schistosoma mansoni and Schistosoma japonicum to praziquantel in mice under laboratorial conditions, and a reduced susceptibility to praziquantel in the field isolates of S. mansoni has been found in many foci. In addition, there are several schistosomiasis cases caused by Schistosoma haematobium infections in which repeated standard treatment fails to clear the infection. However, in the absence of exact mechanisms of action of praziquantel, the mechanisms of drug resistance in schistosomes remain unclear. The present review mainly demonstrates the evidence of drug resistance in the laboratory and field and the mechanism of praziquantel resistance and proposes some strategies for control of praziquantel resistance in schistosomes.

  10. Chemical and Genetic Validation of the Statin Drug Target to Treat the Helminth Disease, Schistosomiasis

    PubMed Central

    Rojo-Arreola, Liliana; Long, Thavy; Asarnow, Dan; Suzuki, Brian M.; Singh, Rahul; Caffrey, Conor R.

    2014-01-01

    The mevalonate pathway is essential in eukaryotes and responsible for a diversity of fundamental synthetic activities. 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) is the rate-limiting enzyme in the pathway and is targeted by the ubiquitous statin drugs to treat hypercholesterolemia. Independent reports have indicated the cidal effects of statins against the flatworm parasite, S. mansoni, and the possibility that SmHMGR is a useful drug target to develop new statin-based anti-schistosome therapies. For six commercially available statins, we demonstrate concentration- and time-dependent killing of immature (somule) and adult S. mansoni in vitro at sub-micromolar and micromolar concentrations, respectively. Cidal activity trends with statin lipophilicity whereby simvastatin and pravastatin are the most and least active, respectively. Worm death is preventable by excess mevalonate, the product of HMGR. Statin activity against somules was quantified both manually and automatically using a new, machine learning-based automated algorithm with congruent results. In addition, to chemical targeting, RNA interference (RNAi) of HMGR also kills somules in vitro and, again, lethality is blocked by excess mevalonate. Further, RNAi of HMGR of somules in vitro subsequently limits parasite survival in a mouse model of infection by up to 80%. Parasite death, either via statins or specific RNAi of HMGR, is associated with activation of apoptotic caspase activity. Together, our genetic and chemical data confirm that S. mansoni HMGR is an essential gene and the relevant target of statin drugs. We discuss our findings in context of a potential drug development program and the desired product profile for a new schistosomiasis drug. PMID:24489942

  11. [Essential issues for project management and quality control in the national schistosomiasis control programme of China].

    PubMed

    Zhou, Xiao-Nong; Li, Shi-Zhu

    2012-08-01

    Based on theoretic management and quality control of the project, this paper summarizes the 3 major management modes in the national schistosomiasis control programme of China, and the health system management mechanisms under the guidance of national legislation, national programme and national standard and regulation. It is revealed that scientific assessment and assurance of the quality of each control programme is one of the highlighted concerns in the management mode of schistosomiasis control in China after a case study on mollusciciding project. Therefore, it is recommended that the actions, including management of every step in the project management of schistosomiasis control, formulation of operation procedure for each control programme and standardization of the working flow for professional staff, are not only a prerequistite to achievment-based evaluation, but also the key to ensure the quality of every control intervention and present the actual control effect.

  12. Rapid diagnosis of schistosomiasis in Yemen using a simple questionnaire and urine reagent strips.

    PubMed

    Bassiouny, H K; Hasab, A A; El-Nimr, N A; Al-Shibani, L A; Al-Waleedi, A A

    2014-05-01

    Schistosomiasis ranks second to malaria in terms of socioeconomic and public health importance in Yemen. This study assessed the validity of a morbidity questionnaire and urine reagent strips as a rapid tool for screening schoolchildren for urinary schistosomiasis as compared with the presence of eggs in urine as the gold-standard parasitological diagnosis. The study examined urine samples and interviewed 696 children (mean age 12.5 years) attending a primary-preparatory school in south Yemen. Urinary schistosomiasis was confirmed in 126 (18.1%) children. Diagnostic performance was poor for 2 items in the morbidity questionnaire (self-reported history of previous infection and self-reported history of antischistosomal treatment). However, self-reported dysuria, self-reported haematuria in the questionnaire and microhaematuria by reagent strips (alone or with macrohaematuria) revealed good diagnostic performance. The results indicated that reagent strips are a valid method for detection of microhaematuria for identifying individuals and communities infected with Schistosoma haematobium.

  13. Malawi study signals need for more research on female genital schistosomiasis.

    PubMed

    1996-06-01

    51 women with urinary schistosomiasis underwent gynecological examinations, including colposcopy and photographic documentation of lesions, in a study conducted in 1994 at Mangochi Hospital near Lake Malawi. Microscopy of genital biopsies determined that 33 women had S. haematobium eggs in their cervix, vagina, and/or vulva. A significant correlation was identified between the size of genital lesion and the number of ova counted. Women with genital pathology had significantly more tumors in the vulva than women with schistosomiasis of the urinary tract only. Most of the observed pathology could be seen with the unaided eye. Even though the sample was very small, significantly more cases of genital schistosomiasis were found in women who had fewer children than desired and whose husbands had children with other women. Reasons for that observation were not investigated. The findings of this pilot study indicate that more research is needed to provide a better understanding of the implications of the disease upon marital and sexual lives.

  14. Modeling and Validation of Environmental Suitability for Schistosomiasis Transmission Using Remote Sensing

    PubMed Central

    Walz, Yvonne; Wegmann, Martin; Dech, Stefan; Vounatsou, Penelope; Poda, Jean-Noël; N'Goran, Eliézer K.; Utzinger, Jürg; Raso, Giovanna

    2015-01-01

    Background Schistosomiasis is the most widespread water-based disease in sub-Saharan Africa. Transmission is governed by the spatial distribution of specific freshwater snails that act as intermediate hosts and human water contact patterns. Remote sensing data have been utilized for spatially explicit risk profiling of schistosomiasis. We investigated the potential of remote sensing to characterize habitat conditions of parasite and intermediate host snails and discuss the relevance for public health. Methodology We employed high-resolution remote sensing data, environmental field measurements, and ecological data to model environmental suitability for schistosomiasis-related parasite and snail species. The model was developed for Burkina Faso using a habitat suitability index (HSI). The plausibility of remote sensing habitat variables was validated using field measurements. The established model was transferred to different ecological settings in Côte d’Ivoire and validated against readily available survey data from school-aged children. Principal Findings Environmental suitability for schistosomiasis transmission was spatially delineated and quantified by seven habitat variables derived from remote sensing data. The strengths and weaknesses highlighted by the plausibility analysis showed that temporal dynamic water and vegetation measures were particularly useful to model parasite and snail habitat suitability, whereas the measurement of water surface temperature and topographic variables did not perform appropriately. The transferability of the model showed significant relations between the HSI and infection prevalence in study sites of Côte d’Ivoire. Conclusions/Significance A predictive map of environmental suitability for schistosomiasis transmission can support measures to gain and sustain control. This is particularly relevant as emphasis is shifting from morbidity control to interrupting transmission. Further validation of our mechanistic model needs

  15. A benzoic acid derivative and flavokawains from Piper species as schistosomiasis vector controls.

    PubMed

    Rapado, Ludmila N; Freitas, Giovana C; Polpo, Adriano; Rojas-Cardozo, Maritza; Rincón, Javier V; Scotti, Marcus T; Kato, Massuo J; Nakano, Eliana; Yamaguchi, Lydia F

    2014-04-23

    The search of alternative compounds to control tropical diseases such as schistosomiasis has pointed to secondary metabolites derived from natural sources. Piper species are candidates in strategies to control the transmission of schistosomiasis due to their production of molluscicidal compounds. A new benzoic acid derivative and three flavokawains from Piper diospyrifolium, P. cumanense and P. gaudichaudianum displayed significant activities against Biomphalaria glabrata snails. Additionally, "in silico" studies were performed using docking assays and Molecular Interaction Fields to evaluate the physical-chemical differences among the compounds in order to characterize the observed activities of the test compounds against Biomphalaria glabrata snails.

  16. Transmission dynamics of schistosomiasis in Zimbabwe: A mathematical and GIS Approach

    NASA Astrophysics Data System (ADS)

    Ngarakana-Gwasira, E. T.; Bhunu, C. P.; Masocha, M.; Mashonjowa, E.

    2016-06-01

    Temperature and presence of water bodies are known to influence the transmission dynamics of schistosomiasis. In this work, effects of water bodies (taken in context of rainfall patterns) and temperature from 1950 to 2000 are considered in the model. With the aid of Geographic Information System (GIS), the reproduction number is mapped on the Zimbabwean country. Results of the mapping show high reproduction numbers along the Lowveld and the Zambezi valley catchment area. High reproduction numbers suggest high levels of schistosomiasis. This result suggests more control efforts should be targeted in these areas with high reproduction numbers.

  17. Experimental and clinical studies with a new antimonial preparation for the treatment of schistosomiasis

    PubMed Central

    Pedrique, Miguel Ron; Ercoli, Nicolò

    1971-01-01

    This paper presents the results of a clinical study in which a new antimony preparation—a chelate of dimethylcysteine with antimony sodium tartrate (”NAP”)—was administered intramuscularly at a total dosage of 2 g (5×400 mg, corresponding to 290 mg of Sb) to 400 patients with schistosomiasis. Among 108 patients in a rural population the treatment was on the whole well accepted (97% completed the intensive course of injections), thus indicating that NAP would be useful for the mass treatment of schistosomiasis. PMID:5317079

  18. A multi-component integrated approach for the elimination of schistosomiasis in the People's Republic of China: design and baseline results of a 4-year cluster-randomised intervention trial.

    PubMed

    Gray, Darren J; Li, Yue-Sheng; Williams, Gail M; Zhao, Zheng-Yuan; Harn, Donald A; Li, Sheng-Ming; Ren, Mao-Yuan; Feng, Zeng; Guo, Feng-Ying; Guo, Jia-Gang; Zhou, Jie; Dong, Yu-Lan; Li, Yuan; Ross, Allen G; McManus, Donald P

    2014-08-01

    Despite major successes in its control over the past 50years, schistosomiasis japonica continues to be a public health problem in the People's Republic of China (P.R. China). Historically, the major endemic foci occur in the lakes and marshlands along the Yangtze River, areas where transmission interruption has proven difficult. The current endemic situation may alter due to the closure of the Three Gorges Dam. Considerable environmental and ecological changes are anticipated that may result in new habitats for the oncomelanid intermediate snail host of Schistosoma japonicum (Sj), thereby increasing the risk of transmission. The current national control program for P.R. China involves a multi-component integrated strategy but, despite targeting multiple transmission pathways, certain challenges remain. As the Chinese government pushes towards elimination, there is a requirement for additional tools, such as vaccination, for long-term prevention. Whereas the zoonotic nature of schistosomiasis japonica adds to the complexity of control, it provides a unique opportunity to develop a transmission blocking vaccine targeting bovines to assist in the prevention of human infection and disease. Mathematical modelling has shown that control options targeting the various transmission pathways of schistosomiasis japonica and incorporating bovine vaccination, mass human chemotherapy and mollusciciding could lead to its elimination from P.R. China. Here we present the study design and baseline results of a four-year cluster randomised intervention trial we are undertaking around the schistosomiasis-endemic Dongting Lake in Hunan Province aimed at determining the impact on schistosome transmission of the multi-component integrated control strategy, including bovine vaccination using a heterologous "prime-boost" delivery platform based on the previously tested SjCTPI vaccine.

  19. Salam's independence

    NASA Astrophysics Data System (ADS)

    Fraser, Gordon

    2009-01-01

    In his kind review of my biography of the Nobel laureate Abdus Salam (December 2008 pp45-46), John W Moffat wrongly claims that Salam had "independently thought of the idea of parity violation in weak interactions".

  20. Low Levels of Awareness Despite High Prevalence of Schistosomiasis among Communities in Nyalenda Informal Settlement, Kisumu City, Western Kenya

    PubMed Central

    Odhiambo, Gladys O.; Musuva, Rosemary M.; Atuncha, Vincent O.; Mutete, Elizabeth T.; Odiere, Maurice R.; Onyango, Rosebella O.; Alaii, Jane A.; Mwinzi, Pauline N. M.

    2014-01-01

    Introduction Intestinal schistosomiasis is widely distributed around Lake Victoria in Kenya where about 16 million people in 56 districts are at risk of the infection with over 9.1 million infected. Its existence in rural settings has been extensively studied compared to urban settings where there is limited information about the disease coupled with low level of awareness. This study therefore assessed community awareness on existence, signs and symptoms, causes, transmission, control and risk factors for contracting schistosomiasis as well as attitudes, health seeking behaviour and environmental antecedents that affect its control so as to identify knowledge gaps that need to be addressed in order to strengthen schistosomiasis control interventions in informal urban settings. Methods The study was carried out in an informal urban settlement where the prevalence of intestinal schistosomiasis was previously reported to be the highest (36%) among the eight informal settlements of Kisumu city. The study adopted cross-sectional design and purposive sampling technique. Eight focus group discussions were conducted with adult community members and eight key informant interviews with opinion leaders. Data was audio recorded transcribed, coded and thematically analyzed using ATLAS.ti version 6 software. Results Most respondents stated having heard about schistosomiasis but very few had the correct knowledge of signs and symptoms, causes, transmission and control of schistosomiasis. However, there was moderate knowledge of risk factors and at high risk groups. Their attitudes towards schistosomiasis and its control were generally indifferent with a general belief that they had no control over their environmental circumstances to reduce transmission. Discussion/Conclusion Although schistosomiasis was prevalent in the study area, majority of the people in the community had low awareness. This study, therefore, stresses the need for health education to raise community

  1. Schistosomiasis and soil-transmitted helminthiasis control in Cameroon and Côte d'Ivoire: implementing control on a limited budget.

    PubMed

    Tchuenté, L A Tchuem; N'goran, E K

    2009-11-01

    Schistosomiasis and soil-transmitted helminthiasis occur throughout the developing world and remain a major public health problem in the poorest communities with enormous consequences for development. The extent of the problem has long been neglected because these diseases rarely kill at a young age and also because of their insidious nature. Today there exists a momentum and an unprecedented opportunity for a cost-effective control of these neglected tropical diseases. The control of these diseases has become a priority on the agenda of many governments, donors and international agencies. This paper highlights the progress made and future control activities in Cameroon and Côte d'Ivoire, where schistosomiasis and soil-transmitted helminthiasis control measures have been implemented over the past decade with limited budgets. In Cameroon, deworming activities were increased to encompass all ten regions in 2007 as a result of a co-ordinated effort of the Ministry of Health and the Ministry of Education with national and international partners. In Côte d'Ivoire, focal control activities were achieved with support from various partners. Prospects, opportunities and challenges for the control of neglected tropical diseases in these two countries are discussed.

  2. Closing the praziquantel treatment gap: new steps in epidemiological monitoring and control of schistosomiasis in African infants and preschool-aged children

    PubMed Central

    STOTHARD, J. RUSSELL; SOUSA-FIGUEIREDO, JOSÉ C.; BETSON, MARTHA; GREEN, HELEN K.; SETO, EDMUND Y. W.; GARBA, AMADOU; SACKO, MOUSSA; MUTAPI, FRANCISCA; VAZ NERY, SUSANA; AMIN, MUTAMAD A.; MUTUMBA-NAKALEMBE, MARGARET; NAVARATNAM, ANNALAN; FENWICK, ALAN; KABATEREINE, NARCIS B.; GABRIELLI, ALBIS F.; MONTRESOR, ANTONIO

    2011-01-01

    SUMMARY Where very young children come into contact with water containing schistosome cercariae, infections occur and schistosomiasis can be found. In high transmission environments, where mothers daily bathe their children with environmentally drawn water, many infants and preschool-aged children have schistosomiasis. This ‘new’ burden, inclusive of co-infections with Schistosoma haematobium and Schistosoma mansoni, is being formally explored as infected children are not presently targeted to receive praziquantel (PZQ) within current preventive chemotherapy campaigns. Thus an important PZQ treatment gap exists whereby infected children might wait up to 4–5 years before receiving first treatment in school. International treatment guidelines, set within national treatment platforms, are presently being modified to provide earlier access to medication(s). Although detailed pharmacokinetic studies are needed, to facilitate pragmatic dosing in the field, an extended ‘dose pole’ has been devised and epidemiological monitoring has shown that administration of PZQ (40 mg/kg), in either crushed tablet or liquid suspension, is both safe and effective in this younger age-class; drug efficacy, however, against S. mansoni appears to diminish after repeated rounds of treatment. Thus use of PZQ should be combined with appropriate health education/water hygiene improvements for both child and mother to bring forth a more enduring solution. PMID:21861945

  3. [On the reversal of schistosomiasis hepatic fibrosis after specific therapy. Histopathologic study].

    PubMed

    Chapadeiro, E; Pitanga, L C

    1997-01-01

    Surgical liver biopsies of patients of both sexes, between 18 and 72 years old, with the compensated hepatoesplenic form of schistosomiasis mansoni, previously treated with oxaminique (Mansil) were studied by histological and immunohistochemical methods. Although the search for parasites and/or granulomas was negative in all specimen studied, the portal fibrosis remained.

  4. Road to the elimination of schistosomiasis from Asia: the journey is far from over

    PubMed Central

    Ross, Allen G.P.; Olveda, Remigio M.; Acosta, Luz; Harn, Donald A.; Chy, Delia; Li, Yuesheng; Gray, Darren J.; Gordon, Catherine A.; McManus, Donald P.; Williams, Gail M.

    2015-01-01

    Schistosomiasis is a neglected tropical disease with a very long endemic history in Asia. Great strides have been made to control the disease in China and the Philippines but the road to elimination is far from over, given the zoonotic nature of the schistosome parasites in both countries. PMID:23973709

  5. Short-Term Efficacy of Laparoscopic Treatment for Colorectal Cancer in Patients with Schistosomiasis Japonica

    PubMed Central

    Hong-Gang, Jiang; Zhi-Heng, Chen; Bo-Hao, Lu

    2016-01-01

    Introduction. Schistosomiasis is associated with numerous complications such as thrombocytopenia, liver cirrhosis, portal hypertension, and colitis. To the best of our knowledge, the feasibility and outcomes of laparoscopic colorectal surgery in patients with schistosomiasis have not yet been studied. Methods. In this study, the data of 280 patients with colorectal carcinoma along with schistosomiasis japonica infection who underwent laparoscopic or open colorectal surgery were retrospectively analyzed. Preoperative data, operative data, pathological outcomes, postoperative complications, and recovery were compared between patients in the laparoscopic (LAC) and open (OC) groups. Results. There were no significant differences in the preoperative data between the groups. However, fewer postoperative complications, especially severe hypoproteinemia, early postoperative feeding, and shorter postoperative hospital stay, were observed in patients in the LAC group (P < 0.001). The mean operative time was higher in the LAC group (180 min versus 158 min; P < 0.001), while the mean blood loss was similar (95 mL versus 108 mL; P = 0.196) between groups. The mean number of lymph nodes harvested was also similar in both groups (15 versus 16; P = 0.133). Conclusion. Laparoscopic surgery for colorectal cancer is safe in patients with schistosomiasis japonica and has better short-term outcomes than open surgery. PMID:27843449

  6. Schistosomiasis: The Social Challenge of Controlling a Man-Made Disease

    ERIC Educational Resources Information Center

    Lemma, Aklilu

    1973-01-01

    There is an indication of a method for curbing or controlling schistosomiasis or bilharziasis. Modern technological advances in applied pharmacology have not provided a satisfactory remedy but a simple natural product, an endod berry, has been used to control the disease on a self-help basis. (EB)

  7. Malaria and schistosomiasis risks associated with surface and sprinkler irrigation systems in Zimbabwe.

    PubMed

    Chimbari, M J; Chirebvu, E; Ndlela, B

    2004-01-01

    A comparative assessment of the malaria and schistosomiasis risks associated with surface and sprinkler irrigation systems in Zimbabwe was carried out. The risk assessment of the two diseases was done in accordance with the three standard components of health impact assessment, namely (i) community vulnerability, (ii) environmental receptivity, and (iii) capability of health services to respond to malaria and schistosomiasis. Records of the two diseases were obtained from four health centres serving two surface irrigation schemes and two sprinkler irrigation schemes. For comparison records were also obtained from health centres serving nearby dryland areas. Incidence of schistosomiasis as estimated from recorded new cases of the disease was much higher in surface irrigation schemes than in sprinkler irrigation schemes. For malaria it was the other way around. These findings were confirmed by rapid risk assessments. Malaria risk factors were more prominent in sprinkler irrigation schemes, whereas more schistosomiasis risk factors were identified in surface irrigation schemes. These observations were attributed to poorly maintained infrastructure and inadequate landscape-levelling, which created mosquito breeding sites within the fields in the case of sprinkler schemes, and to poor drainage structures, which created snail-breeding sites in the case of surface-irrigation schemes. Importantly, poor maintenance of sprinkler scheme infrastructure accounted for more disease promoting features than the engineering designs per se. This study demonstrated the value of complementing routinely collected health data with rapid assessment procedures for appraisal of commonly reported diseases.

  8. [Schistosomiasis must be eradicated: a review of fighting schitosomiasis in Qingpu, Shanghai].

    PubMed

    Yu, S Z

    2016-07-01

    Qingpu, in western suburban of Shanghai, was one of serious schistosomiasis endemic counties in China. In 1958, in response to Chairman Mao' s call " Schistosomiasis must be eradicated", Shanghai First Medical College organized a research group to carry out schitosomiasis control in Qingpu. The prevalence of schistosomiasis was about 39% in 390 000 people and 8.4% in cattle. Oncomelania was distributed in an area of 70 million meter(2). The fighting project could be divided into two steps, the first one was from 1958 to 1974, during this period, the epidemic survey and patient treatment were conducted, and oncomelania control was carried out by using different kind of molluscides. In 1975, up to 92% of patients were cured, and 98% of oncomelania were killed. The second step was from 1975 to 1985, the main tasks were the consolidation of control achievement and surveillance. During this period oral medicines were used instead of venous injections. After the improvement of oncomelania detection method, the oncomelania clustering were found under rock duck and brick shore. In 1985, it was confirmed that schistosomiasis had been eradicated in Qingpu and other suburb areas of Shanghai.

  9. The roles of water, sanitation and hygiene in reducing schistosomiasis: a review.

    PubMed

    Grimes, Jack E T; Croll, David; Harrison, Wendy E; Utzinger, Jürg; Freeman, Matthew C; Templeton, Michael R

    2015-03-13

    Schistosomiasis is a disease caused by infection with blood flukes of the genus Schistosoma. Transmission of, and exposure to, the parasite result from faecal or urinary contamination of freshwater containing intermediate host snails, and dermal contact with the same water. The World Health Assembly resolution 65.21 from May 2012 urges member states to eliminate schistosomiasis through preventive chemotherapy (i.e. periodic large-scale administration of the antischistosomal drug praziquantel to school-aged children and other high-risk groups), provision of water, sanitation and hygiene (WASH) and snail control. However, control measures focus almost exclusively on preventive chemotherapy, while only few studies made an attempt to determine the impact of upgraded access to safe water, adequate sanitation and good hygiene on schistosome transmission. We recently completed a systematic review and meta-analysis pertaining to WASH and schistosomiasis and found that people with safe water and adequate sanitation have significantly lower odds of a Schistosoma infection. Importantly though, the transmission of schistosomiasis is deeply entrenched in social-ecological systems, and hence is governed by setting-specific cultural and environmental factors that determine human behaviour and snail populations. Here, we provide a comprehensive review of the literature, which explores the transmission routes of schistosomes, particularly focussing on how these might be disrupted with WASH-related technologies and human behaviour. Additionally, future research directions in this area are highlighted.

  10. Arginase activity in peripheral blood of patients with intestinal schistosomiasis, Wonji, Central Ethiopia.

    PubMed

    Getaneh, A; Tamrat, A; Tadesse, K

    2015-07-01

    Morbidity and mortality caused by schistosomiasis usually results from immunopathology. But the underlying mechanisms are not yet clearly understood. Th2-type immune response is thought to be dominant during chronic schistosomiasis, and upregulation of arginase-I is one component of this milieu. A cohort study was conducted to assess arginase activity in peripheral blood of humans with intestinal schistosomiasis in Wonji-Shoa Sugar Estate, Central Ethiopia. Laboratory-confirmed 30 Schistosoma mansoni-infected patients and 18 apparently healthy controls were recruited. Faecal egg count was carried out by Kato-Katz technique. Plasma and peripheral blood mononuclear cells (PBMCs) were isolated from whole blood. Activity of arginase in plasma and PBMC lysates was measured, and results were compared with that of controls. Twenty-one of 30 patients had light infection, whereas moderate and heavy intensity infections were observed in eight and only one patient(s), respectively. A significant increase in both PBMC (patients: 59.96 + 82.99, controls: 25.44 + 24.6 mU/mg protein, P < 0.0001) and plasma (patients: 1.61 + 2.19, controls: 0.31 + 0.73 mU/mL plasma, P < 0.0001) arginase activity was observed during human S. mansoni infection. Arginase activity increases in peripheral blood of patients with intestinal schistosomiasis.

  11. [Research of prevalence of schistosomiasis in Hunan province, 1984-2015].

    PubMed

    Li, F Y; Tan, H Z; Ren, G H; Jiang, Q; Wang, H L

    2017-03-10

    Objective: To analyze the prevalence of schistosomiasis in Hunan province, and provide scientific evidence for the control and elimination of schistosomiasis. Methods: The changes of infection rates of Schistosoma (S.) japonicum among residents and cattle in Hunan from 1984 to 2015 were analyzed by using dynamic trend diagram; and the time regression model was used to fit the infection rates of S. japonicum, and predict the recent infection rate. Results: The overall infection rates of S. japonicum in Hunan from 1984 to 2015 showed downward trend (95.29% in residents and 95.16% in cattle). By using the linear regression model, the actual values of infection rates in residents and cattle were all in the 95% confidence intervals of the value predicted; and the prediction showed that the infection rates in the residents and cattle would continue to decrease from 2016 to 2020. Conclusion: The prevalence of schistosomiasis was in decline in Hunan. The regression model has a good effect in the short-term prediction of schistosomiasis prevalence.

  12. Risk analysis for occurrences of schistosomiasis in the coastal area of Porto de Galinhas, Pernambuco, Brazil

    PubMed Central

    2014-01-01

    Background Manson’s schistosomiasis continues to be a severe public health problem in Brazil, where thousands of people live under the risk of contracting this parasitosis. In the Northeast of Brazil, schistosomiasis has expanded from rural areas to the coast of Pernambuco State, where the intermediate host is Biomphalaria glabrata snails. This study aims at presenting situational analyses on schistosomiasis at the coastal locality of Porto de Galinhas, Pernambuco, Brazil, by determining the risk factors relating to its occurrence from the epidemiological and spatial perspectives. Methods In order to gather prevalence data, a parasitological census surveys were conducted in 2010 in the light of the Kato-Katz technique. Furthermore, malacological surveys were also conducted in the same years so as to define the density and infection rates of the intermediate host. Lastly, socioeconomic-behavioral survey was also conducted to determine the odds ratio for infection by Schistosoma mansoni. Based on these data, spatial analyses were done, resulting in maps of the risk of disease transmission. To predict the risk of schistosomiasis occurrence, a multivariate logistic regression was performed using R 2.13 software. Results Based on prevalence, malacological and socioeconomic-behavioural surveys, it was identified a prevalence of 15.7% in the investigated population (2,757 individuals). Due to the malacological survey, 36 breeding sites were identified, of which 11 were classified as foci of schistosomiasis transmission since they pointed out snails which were infected by Schistosoma mansoni. Overall, 11,012 snails (Biomphalaria glabrata) were collected. The multivariate regression model identified six explanatory variables of environmental, socioeconomic and demographic nature. Spatial sweep analysis by means of the Bernoulli method identified one statistically significant cluster in Salinas (RR = 2.2; p-value < 0.000), the district with the highest occurrence

  13. Integrated Schistosomiasis and Soil-Transmitted Helminthiasis Control over Five Years on Kome Island, Tanzania.

    PubMed

    Kaatano, Godfrey M; Siza, Julius E; Mwanga, Joseph R; Min, Duk-Yong; Yong, Tai-Soon; Chai, Jong-Yil; Ko, Yunsuk; Chang, Su Young; Kullaya, Cyril M; Rim, Han-Jong; Changalucha, John M; Eom, Keeseon S

    2015-10-01

    Integrated control strategies are important for sustainable control of schistosomiasis and soil-transmitted helminthiasis, despite their challenges for their effective implementation. With the support of Good Neighbors International in collaboration with National Institute of Medical Research, Mwanza, Tanzania, integrated control applying mass drug administration (MDA), health education using PHAST, and improved safe water supply has been implemented on Kome Island over 5 years for controlling schistosomiasis and soil-transmitted helminths (STHs). Baseline surveys for schistosomiasis and STHs was conducted before implementation of any integrated control strategies, followed by 4 cross-sectional follow-up surveys on randomly selected samples of schoolchildren and adults in 10 primary schools and 8 villages, respectively, on Kome islands. Those follow-up surveys were conducted for impact evaluation after introduction of control strategies interventions in the study area. Five rounds of MDA have been implemented from 2009 along with PHAST and improved water supply with pumped wells as other control strategies for complementing MDA. A remarkable steady decline of schistosomiasis and STHs was observed from 2009 to 2012 with significant trends in their prevalence decline, and thereafter infection rate has remained at a low sustainable control. By the third follow-up survey in 2012, Schistosoma mansoni infection prevalence was reduced by 90.5% and hookworm by 93.3% among schoolchildren while in adults the corresponding reduction was 83.2% and 56.9%, respectively. Integrated control strategies have successfully reduced S. mansoni and STH infection status to a lower level. This study further suggests that monitoring and evaluation is a crucial component of any large-scale STH and schistosomiasis intervention.

  14. Integrated Schistosomiasis and Soil-Transmitted Helminthiasis Control over Five Years on Kome Island, Tanzania

    PubMed Central

    Kaatano, Godfrey M.; Siza, Julius E.; Mwanga, Joseph R.; Min, Duk-Yong; Yong, Tai-Soon; Chai, Jong-Yil; Ko, Yunsuk; Chang, Su Young; Kullaya, Cyril M.; Rim, Han-Jong; Changalucha, John M.; Eom, Keeseon S.

    2015-01-01

    Integrated control strategies are important for sustainable control of schistosomiasis and soil-transmitted helminthiasis, despite their challenges for their effective implementation. With the support of Good Neighbors International in collaboration with National Institute of Medical Research, Mwanza, Tanzania, integrated control applying mass drug administration (MDA), health education using PHAST, and improved safe water supply has been implemented on Kome Island over 5 years for controlling schistosomiasis and soil-transmitted helminths (STHs). Baseline surveys for schistosomiasis and STHs was conducted before implementation of any integrated control strategies, followed by 4 cross-sectional follow-up surveys on randomly selected samples of schoolchildren and adults in 10 primary schools and 8 villages, respectively, on Kome islands. Those follow-up surveys were conducted for impact evaluation after introduction of control strategies interventions in the study area. Five rounds of MDA have been implemented from 2009 along with PHAST and improved water supply with pumped wells as other control strategies for complementing MDA. A remarkable steady decline of schistosomiasis and STHs was observed from 2009 to 2012 with significant trends in their prevalence decline, and thereafter infection rate has remained at a low sustainable control. By the third follow-up survey in 2012, Schistosoma mansoni infection prevalence was reduced by 90.5% and hookworm by 93.3% among schoolchildren while in adults the corresponding reduction was 83.2% and 56.9%, respectively. Integrated control strategies have successfully reduced S. mansoni and STH infection status to a lower level. This study further suggests that monitoring and evaluation is a crucial component of any large-scale STH and schistosomiasis intervention. PMID:26537032

  15. Diagnostic Tests to Support Late-Stage Control Programs for Schistosomiasis and Soil-Transmitted Helminthiases

    PubMed Central

    Cantera, Jason L.; Storey, Helen L.; Leader, Brandon T.; de los Santos, Tala

    2016-01-01

    Global efforts to address schistosomiasis and soil-transmitted helminthiases (STH) include deworming programs for school-aged children that are made possible by large-scale drug donations. Decisions on these mass drug administration (MDA) programs currently rely on microscopic examination of clinical specimens to determine the presence of parasite eggs. However, microscopy-based methods are not sensitive to the low-intensity infections that characterize populations that have undergone MDA. Thus, there has been increasing recognition within the schistosomiasis and STH communities of the need for improved diagnostic tools to support late-stage control program decisions, such as when to stop or reduce MDA. Failure to adequately address the need for new diagnostics could jeopardize achievement of the 2020 London Declaration goals. In this report, we assess diagnostic needs and landscape potential solutions and determine appropriate strategies to improve diagnostic testing to support control and elimination programs. Based upon literature reviews and previous input from experts in the schistosomiasis and STH communities, we prioritized two diagnostic use cases for further exploration: to inform MDA-stopping decisions and post-MDA surveillance. To this end, PATH has refined target product profiles (TPPs) for schistosomiasis and STH diagnostics that are applicable to these use cases. We evaluated the limitations of current diagnostic methods with regards to these use cases and identified candidate biomarkers and diagnostics with potential application as new tools. Based on this analysis, there is a need to develop antigen-detecting rapid diagnostic tests (RDTs) with simplified, field-deployable sample preparation for schistosomiasis. Additionally, there is a need for diagnostic tests that are more sensitive than the current methods for STH, which may include either a field-deployable molecular test or a simple, low-cost, rapid antigen-detecting test. PMID:28005900

  16. Intestinal schistosomiasis among preschool children along the shores of Lake Victoria in Uganda.

    PubMed

    Nalugwa, A; Olsen, A; Tukahebwa, M E; Nuwaha, F

    2015-02-01

    Schistosomiasis, a disease caused by Schistosoma trematode parasites, affects hundreds of millions of people and accounts for more than 40% of the global health burden due to neglected tropical diseases. In Uganda, intestinal schistosomiasis is endemic in 73 out of 112 districts and about 55% of the population of 36 million individuals are at risk. There is scanty information on the status and burden of schistosomiasis in preschool children less than six years of age in Uganda. This study aimed to assess the status of Schistosoma mansoni infections in children aged 1-5 years in Uganda. S. mansoni prevalence and intensity of infection were examined in 3058 children from 5 districts along Lake Victoria shoreline, eastern Uganda. For each child one stool sample was collected on three consecutive days. The Kato-Katz technique was used to prepare stool smears on slides for microscopic examination. Short interviews with a standardized pre-tested questionnaire prepared in the local language (Lusoga) were administered to each caregiver to identify risk factors associated with S. mansoni infection. An overall S. mansoni prevalence of 39.3% (95% CI: 38.0-41.1%) was estimated out of the 3058 stool samples examined. The geometric mean intensity of S. mansoni among the infected children was 273 (95% CI: 241-305) eggs per gram of faeces. Both prevalence and intensity of infection increased linearly with age (P<0.0001) and were highest in the age group 49-60 months. Majority (61%) of the children, especially in the age group 12-24 months (84.2%; 95% CI: 75.6-90.1%), were lightly infected. Short interviews with caregivers revealed that preschool children, 1-5 years old, get exposed to S. mansoni infested waters through bathing, playing or swimming. It is important that the Uganda national control programme for schistosomiasis takes preschool children into consideration and that health education on transmission of schistosomiasis is delivered to the endemic communities regularly.

  17. Complete rectal prolapse in young Egyptian males: Is schistosomiasis really condemned?

    PubMed Central

    Abou-Zeid, Ahmed A; ElAbbassy, Islam H; Kamal, Ahmed M; Somaie, Dina A

    2016-01-01

    AIM To investigate the assumption that schistosomiasis is the main cause of rectal prolapse in young Egyptian males. METHODS Twenty-one male patients between ages of 18 and 50 years with complete rectal prolapse were included in the study out of a total 29 patients with rectal prolapse admitted for surgery at Colorectal Surgery Unit, Ain Shams University hospitals between the period of January 2011 and April 2014. Patients were asked to fill out a specifically designed questionnaire about duration of the prolapse, different bowel symptoms and any past or present history of schistosomiasis. Patients also underwent flexible sigmoidoscopy and four quadrant mid-rectal biopsies documenting any gross or microscopic rectal pathology. Data from questionnaire and pathology results were analyzed and patients were categorized according to their socioeconomic class. RESULTS Twelve patients (57%) never contracted schistosomiasis and were never susceptible to the disease, nine patients (43%) had history of the disease but were properly treated. None of the patients had gross rectal polyps and none of the patients had active schistosomiasis on histopathological examination. Fifteen patients (71%) had early onset prolapse that started in childhood, majority before the age of 5 years. Thirteen patients (62%) were habitual strainers, and four of them (19%) had straining dating since early childhood. Four patients (19%) stated that prolapse followed a period of straining that ranged between 8 mo and 2 years. Nine patients (43%) in the present study came from the low social class, 10 patients (48%) came from the working class and 2 patients (9%) came from the low middle social class. CONCLUSION Schistosomiasis should not be considered the main cause of rectal prolapse among young Egyptian males. Childhood prolapse that continues through adult life is likely involved. Childhood prolapse probably results from malnutrition, recurrent parasitic infections and diarrhea that induce

  18. Independent Living.

    ERIC Educational Resources Information Center

    Nathanson, Jeanne H., Ed.

    1994-01-01

    This issue of "OSERS" addresses the subject of independent living of individuals with disabilities. The issue includes a message from Judith E. Heumann, the Assistant Secretary of the Office of Special Education and Rehabilitative Services (OSERS), and 10 papers. Papers have the following titles and authors: "Changes in the…

  19. Immunoprotection of Mice against Schistosomiasis Mansoni Using Solubilized Membrane Antigens

    PubMed Central

    Sulbarán, Guidenn; Noya, Oscar; Brito, Beatríz; Ballén, Diana E.; Cesari, Italo M.

    2013-01-01

    Background Schistosomiasis continues to be one of the most prevalent parasitic diseases in the world. Despite the existence of a highly effective antischistosome drug, the disease is spreading into new areas, and national control programs do not arrive to complete their tasks particularly in low endemic areas. The availability of a vaccine could represent an additional component to chemotherapy. Experimental vaccination studies are however necessary to identify parasite molecules that would serve as vaccine candidates. In the present work, C57BL/6 female mice were subcutaneously immunized with an n-butanol extract of the adult worm particulate membranous fraction (AWBE) and its protective effect against a S. mansoni challenge infection was evaluated. Methodology and Findings Water-saturated n-butanol release into the aqueous phase a set of membrane-associated (glyco)proteins that are variably recognized by antibodies in schistosome-infected patients; among the previously identified AWBE antigens there is Alkaline Phosphatase (SmAP) which has been associated with resistance to the infection in mice. As compared to control, a significantly lower number of perfuse parasites was obtained in the immunized/challenged mouse group (P<0.05, t test); and consequently, a lower number of eggs and granulomas (with reduced sizes), overall decreasing pathology. Immunized mice produced high levels of sera anti-AWBE IgG recognizing antigens of ∼190-, 130-, 98-, 47-, 28-23, 14-, and 9-kDa. The ∼130-kDa band (the AP dimer) exhibited in situ SmAP activity after addition of AP substrate and the activity was not apparently inhibited by host antibodies. A preliminary proteomic analysis of the 25-, 27-, and 28-kDa bands in the immunodominant 28–23 kDa region suggested that they are composed of actin. Conclusions Immunization with AWBE induced the production of specific antibodies to various adult worm membrane molecules (including AP) and a partial (43%) protection against a

  20. Ivermectin efficacy against Biomphalaria, intermediate host snail vectors of Schistosomiasis.

    PubMed

    Katz, Naftale; Araújo, Neusa; Coelho, Paulo Marcos Zech; Morel, Carlos Medicis; Linde-Arias, Ana Rosa; Yamada, Takeshi; Horimatsu, Yuki; Suzuki, Koh; Sunazuka, Toshiaki; Ōmura, Satoshi

    2017-03-15

    The impact of ivermectin on adult snails of the genus Biomphalaria (B. glabrata, B. tenagophila and B. straminea), B. glabrata infected with Schistosoma mansoni, snail egg-masses cercariae and miracidia, as well as on guppy fish (Poecilia reticulata) was examined and evaluated. Biomphalaria snails, egg-masses, parasite stages and guppies were all exposed to different concentrations of ivermectin for 24 h, followed by regular observations of mortality. The calculated lethal doses of ivermectin were around an LD50 of 0.03 μg ml(-1), and an LD90 of 0.3 μg ml(-1) for the three species of snails. Specimens of B. glabrata actually shedding parasite cercariae all died when exposed to ivermectin at a concentration of a mere 0.01 μg ml(-1). Ivermectin B1a, the major (80%) component of commercially available ivermectin, proved to be inactive, and it was the minor (20%) component, ivermectin B1b, which caused snail death. Snail egg-masses were not affected, even at the highest concentration of 100 μg ml(-1). With respect to S. mansoni parasite stages, 0.2 μg ml(-1) ivermectin killed 50% of cercariae and miracidia within five minutes, rising to 90% after 30 min. Mortality of guppy fish within 24 h of exposure to ivermectin at concentrations of 0.5 μg ml(-1) and 0.01 μg ml(-1), were 100% and 30%, respectively. The concentration of 0.01 μg ml(-1) that killed Schistosoma mansoni-infected snails only caused 30% mortality in guppy fish. Ivermectin can be considered a promising molluscicide, especially as it is more potent against infected snails than uninfected ones, although it has no impact on egg-masses. Ivermectin and its derivatives could be explored in the search for a new agent to help control schistosomiasis transmission.The Journal of Antibiotics advance online publication, 15 March 2017; doi:10.1038/ja.2017.31.

  1. Radiology corner. Answer to last month's radiology case and images: Schistosomiasis japonicum involving the liver and colon.

    PubMed

    Ly, Justin Q; Sanders, Timothy G; Folio, Les

    2007-02-01

    Abdominal radiography showed subtle curvilinear densities overlying the left lower quadrant and central within the pelvis (Fig. 1a). This was confirmed on intravenous contrast-enhanced abdominopelvic CT to be caused by thin mucosal surface calcifications within the descending and sigmoid colons (Fig. 1b, c). Incidental note is made of thin right hepatic lobe capsule calcifications (Fig. 1d). These colonic and hepatic calcifications are characteristic of Schistosomiasis infection of the gastrointestinal tract. Liver biopsy confirmed Schistosomiasis japonicum infection.

  2. Understanding independence

    NASA Astrophysics Data System (ADS)

    Annan, James; Hargreaves, Julia

    2016-04-01

    In order to perform any Bayesian processing of a model ensemble, we need a prior over the ensemble members. In the case of multimodel ensembles such as CMIP, the historical approach of ``model democracy'' (i.e. equal weight for all models in the sample) is no longer credible (if it ever was) due to model duplication and inbreeding. The question of ``model independence'' is central to the question of prior weights. However, although this question has been repeatedly raised, it has not yet been satisfactorily addressed. Here I will discuss the issue of independence and present a theoretical foundation for understanding and analysing the ensemble in this context. I will also present some simple examples showing how these ideas may be applied and developed.

  3. Reduced transmission of human schistosomiasis after restoration of a native river prawn that preys on the snail intermediate host.

    PubMed

    Sokolow, Susanne H; Huttinger, Elizabeth; Jouanard, Nicolas; Hsieh, Michael H; Lafferty, Kevin D; Kuris, Armand M; Riveau, Gilles; Senghor, Simon; Thiam, Cheikh; N'Diaye, Alassane; Faye, Djibril Sarr; De Leo, Giulio A

    2015-08-04

    Eliminating human parasitic disease often requires interrupting complex transmission pathways. Even when drugs to treat people are available, disease control can be difficult if the parasite can persist in nonhuman hosts. Here, we show that restoration of a natural predator of a parasite's intermediate hosts may enhance drug-based schistosomiasis control. Our study site was the Senegal River Basin, where villagers suffered a massive outbreak and persistent epidemic after the 1986 completion of the Diama Dam. The dam blocked the annual migration of native river prawns (Macrobrachium vollenhoveni) that are voracious predators of the snail intermediate hosts for schistosomiasis. We tested schistosomiasis control by reintroduced river prawns in a before-after-control-impact field experiment that tracked parasitism in snails and people at two matched villages after prawns were stocked at one village's river access point. The abundance of infected snails was 80% lower at that village, presumably because prawn predation reduced the abundance and average life span of latently infected snails. As expected from a reduction in infected snails, human schistosomiasis prevalence was 18 ± 5% lower and egg burden was 50 ± 8% lower at the prawn-stocking village compared with the control village. In a mathematical model of the system, stocking prawns, coupled with infrequent mass drug treatment, eliminates schistosomiasis from high-transmission sites. We conclude that restoring river prawns could be a novel contribution to controlling, or eliminating, schistosomiasis.

  4. Reduced transmission of human schistosomiasis after restoration of a native river prawn that preys on the snail intermediate host

    USGS Publications Warehouse

    Sokolow, Susanne H.; Huttinger, Elizabeth; Jouanard, Nicolas; Hsieh, Michael H.; Lafferty, Kevin D.; Kuris, Armand M.; Riveau, Gilles; Senghor, Simon; Thiam, Cheikh; D'Diaye, Alassane; Faye, Djibril Sarr; De Leo, Giulio A.

    2015-01-01

    Eliminating human parasitic disease often requires interrupting complex transmission pathways. Even when drugs to treat people are available, disease control can be difficult if the parasite can persist in nonhuman hosts. Here, we show that restoration of a natural predator of a parasite’s intermediate hosts may enhance drug-based schistosomiasis control. Our study site was the Senegal River Basin, where villagers suffered a massive outbreak and persistent epidemic after the 1986 completion of the Diama Dam. The dam blocked the annual migration of native river prawns (Macrobrachium vollenhoveni) that are voracious predators of the snail intermediate hosts for schistosomiasis. We tested schistosomiasis control by reintroduced river prawns in a before-after-control-impact field experiment that tracked parasitism in snails and people at two matched villages after prawns were stocked at one village’s river access point. The abundance of infected snails was 80% lower at that village, presumably because prawn predation reduced the abundance and average life span of latently infected snails. As expected from a reduction in infected snails, human schistosomiasis prevalence was 18 ± 5% lower and egg burden was 50 ± 8% lower at the prawn-stocking village compared with the control village. In a mathematical model of the system, stocking prawns, coupled with infrequent mass drug treatment, eliminates schistosomiasis from high-transmission sites. We conclude that restoring river prawns could be a novel contribution to controlling, or eliminating, schistosomiasis.                            

  5. Reduced transmission of human schistosomiasis after restoration of a native river prawn that preys on the snail intermediate host

    PubMed Central

    Sokolow, Susanne H.; Huttinger, Elizabeth; Jouanard, Nicolas; Hsieh, Michael H.; Lafferty, Kevin D.; Kuris, Armand M.; Riveau, Gilles; Senghor, Simon; Thiam, Cheikh; N’Diaye, Alassane; Faye, Djibril Sarr; De Leo, Giulio A.

    2015-01-01

    Eliminating human parasitic disease often requires interrupting complex transmission pathways. Even when drugs to treat people are available, disease control can be difficult if the parasite can persist in nonhuman hosts. Here, we show that restoration of a natural predator of a parasite’s intermediate hosts may enhance drug-based schistosomiasis control. Our study site was the Senegal River Basin, where villagers suffered a massive outbreak and persistent epidemic after the 1986 completion of the Diama Dam. The dam blocked the annual migration of native river prawns (Macrobrachium vollenhoveni) that are voracious predators of the snail intermediate hosts for schistosomiasis. We tested schistosomiasis control by reintroduced river prawns in a before-after-control-impact field experiment that tracked parasitism in snails and people at two matched villages after prawns were stocked at one village’s river access point. The abundance of infected snails was 80% lower at that village, presumably because prawn predation reduced the abundance and average life span of latently infected snails. As expected from a reduction in infected snails, human schistosomiasis prevalence was 18 ± 5% lower and egg burden was 50 ± 8% lower at the prawn-stocking village compared with the control village. In a mathematical model of the system, stocking prawns, coupled with infrequent mass drug treatment, eliminates schistosomiasis from high-transmission sites. We conclude that restoring river prawns could be a novel contribution to controlling, or eliminating, schistosomiasis. PMID:26195752

  6. Sources and Distribution of Surface Water Fecal Contamination and Prevalence of Schistosomiasis in a Brazilian Village

    PubMed Central

    Ponce-Terashima, Rafael; Koskey, Amber M.; Reis, Mitermayer G.; McLellan, Sandra L.; Blanton, Ronald E.

    2014-01-01

    Background The relationship between poor sanitation and the parasitic infection schistosomiasis is well-known, but still rarely investigated directly and quantitatively. In a Brazilian village we correlated the spatial concentration of human fecal contamination of its main river and the prevalence of schistosomiasis. Methods We validated three bacterial markers of contamination in this population by high throughput sequencing of the 16S rRNA gene and qPCR of feces from local residents. The qPCR of genetic markers from the 16S rRNA gene of Bacteroides-Prevotella group, Bacteroides HF8 cluster, and Lachnospiraceae Lachno2 cluster as well as sequencing was performed on georeferenced samples of river water. Ninety-six percent of residents were examined for schistosomiasis. Findings Sequence of 16S rRNA DNA from stool samples validated the relative human specificity of the HF8 and Lachno 2 fecal indicators compared to animals. The concentration of fecal contamination increased markedly along the river as it passed an increasing proportion of the population on its way downstream as did the sequence reads from bacterial families associated with human feces. Lachnospiraceae provided the most robust signal of human fecal contamination. The prevalence of schistosomiasis likewise increased downstream. Using a linear regression model, a significant correlation was demonstrated between the prevalence of S. mansoni infection and local concentration of human fecal contamination based on the Lachnospiraceae Lachno2 cluster (r2 0.53) as compared to the correlation with the general fecal marker E. coli (r2 0.28). Interpretation Fecal contamination in rivers has a downstream cumulative effect. The transmission of schistosomiasis correlates with very local factors probably resulting from the distribution of human fecal contamination, the limited movement of snails, and the frequency of water contact near the home. In endemic regions, the combined use of human associated bacterial

  7. Malacological survey and geographical distribution of vector snails for schistosomiasis within informal settlements of Kisumu City, western Kenya

    PubMed Central

    2011-01-01

    Background Although schistosomiasis is generally considered a rural phenomenon, infections have been reported within urban settings. Based on observations of high prevalence of Schistosoma mansoni infection in schools within the informal settlements of Kisumu City, a follow-up malacological survey incorporating 81 sites within 6 informal settlements of the City was conducted to determine the presence of intermediate host snails and ascertain whether active transmission was occurring within these areas. Methods Surveyed sites were mapped using a geographical information system. Cercaria shedding was determined from snails and species of snails identified based on shell morphology. Vegetation cover and presence of algal mass at the sites was recorded, and the physico-chemical characteristics of the water including pH and temperature were determined using a pH meter with a glass electrode and a temperature probe. Results Out of 1,059 snails collected, 407 (38.4%) were putatively identified as Biomphalaria sudanica, 425 (40.1%) as Biomphalaria pfeifferi and 227 (21.5%) as Bulinus globosus. The spatial distribution of snails was clustered, with few sites accounting for most of the snails. The highest snail abundance was recorded in Nyamasaria (543 snails) followed by Nyalenda B (313 snails). As expected, the mean snail abundance was higher along the lakeshore (18 ± 12 snails) compared to inland sites (dams, rivers and springs) (11 ± 32 snails) (F1, 79 = 38.8, P < 0.0001). Overall, 19 (1.8%) of the snails collected shed schistosome cercariae. Interestingly, the proportion of infected Biomphalaria snails was higher in the inland (2.7%) compared to the lakeshore sites (0.3%) (P = 0.0109). B. sudanica was more abundant in sites along the lakeshore whereas B. pfeifferi and B. globosus were more abundant in the inland sites. Biomphalaria and Bulinus snails were found at 16 and 11 out of the 56 inland sites, respectively. Conclusions The high abundance of Biomphalaria and

  8. Blockade of PD-1 Signaling Enhances Th2 Cell Responses and Aggravates Liver Immunopathology in Mice with Schistosomiasis japonica

    PubMed Central

    Zhou, Sha; Jin, Xin; Li, Yalin; Li, Wei; Chen, Xiaojun; Xu, Lei; Zhu, Jifeng; Xu, Zhipeng; Zhang, Yang; Liu, Feng; Su, Chuan

    2016-01-01

    Background More than 220 million people worldwide are chronically infected with schistosomes, causing severe disease or even death. The major pathological damage occurring in schistosomiasis is attributable to the granulomatous inflammatory response and liver fibrosis induced by schistosome eggs. The inflammatory response is tightly controlled and parallels immunosuppressive regulation, constantly maintaining immune homeostasis and limiting excessive immunopathologic damage in important host organs. It is well known that the activation of programmed death 1 (PD-1) signaling causes a significant suppression of T cell function. However, the roles of PD-1 signaling in modulating CD4+ T cell responses and immunopathology during schistosome infection, have yet to be defined. Methodology/Principal Findings Here, we show that PD-1 is upregulated in CD4+ T cells in Schistosoma japonicum (S. japonicum)-infected patients. We also show the upregulation of PD-1 expression in CD4+ T cells in the spleens, mesenteric lymph nodes, and livers of mice with S. japonicum infection. Finally, we found that the blockade of PD-1 signaling enhanced CD4+ T helper 2 (Th2) cell responses and led to more severe liver immunopathology in mice with S. japonicum infection, without a reduction of egg production or deposition in the host liver. Conclusions/Significance Overall, our study suggests that PD-1 signaling is specifically induced to control Th2-associated inflammatory responses during schistosome infection and is beneficial to the development of PD-1-based control of liver immunopathology. PMID:27792733

  9. Ineffectiveness of myrrh-derivative Mirazid against schistosomiasis and fascioliasis in humans.

    PubMed

    Osman, M M; El-Taweel, H A; Shehab, A Y; Farag, H F

    2010-09-01

    The present study assessed the schistosomicidal and fasciolicidal actions of the myrrh-derivative Mirazid in an area of low schistosomiasis transmission. A total of 27 patients infected with Schistosoma mansoni and 16 with Fasciola spp. received the maximum recommended dose of Mirazid. Pretreatment egg counts in 4 Kato-Katz slides were compared with similar counts in stool samples collected 1 and 2 months after treatment. Standard procedures and quality control measures were followed. The results revealed that Mirazid used as schistosomicidal or fasciolicidal agent in the maximum recommended dose has a low cure rate and produced a negligible reduction in egg counts. Prescribing such an ineffective drug in Egypt might endanger the achievements of the schistosomiasis control strategy.

  10. Re-emerging schistosomiasis in hilly and mountainous areas of Sichuan, China.

    PubMed Central

    Liang, Song; Yang, Changhong; Zhong, Bo; Qiu, Dongchuan

    2006-01-01

    Despite great strides in schistosomiasis control over the past several decades in Sichuan Province, China the disease has re-emerged in areas where it was previously controlled. We reviewed historical records and found that schistosomiasis had re-emerged in eight counties by the end of 2004 - seven of 21 counties with transmission control and one of 25 with transmission interruption as reported in 2001 were confirmed to have local disease transmission. The average "return time" (from control to re-emergence) was about eight years. The onset of re-emergence was commonly signalled by the occurrence of acute infections. Our survey results suggest that environmental and sociopolitical factors play an important role in re-emergence. The main challenge would be to consolidate and maintain effective control in the longer term until "real" eradication is achieved. This would be possible only by the formulation of a sustainable surveillance and control system. PMID:16501732

  11. Large Water Management Projects and Schistosomiasis Control, Dongting Lake Region, China

    PubMed Central

    Li, Yue-Sheng; Zhao, Zheng-Yuan; He, Yong-Kang; Ellis, Magda K.; McManus, Donald P.

    2007-01-01

    Construction of the Three Gorges Dam across the Yangtze River will substantially change the ecology of the Dongting Lake in southern China. In addition, the Central and Hunan Provinces’ governmental authorities have instigated a Return Land to Lake Program that will extend the Dongting Lake surface area from the current 2,681 km2 to 4,350 km2.The previous construction of embankments and the large silt deposits made by the Yangtze River and other connecting rivers have contributed to frequent disastrous flooding. As a consequence of the 2 water projects, >2 million persons and their domestic animals are being resettled. This article provides an overview of the historical background of these 2 large water management projects, the associated population movement, and their impact on future transmission and control of schistosomiasis in the Dongting Lake area. The dam will likely substantially extend the range of the snail habitats and increase schistosome transmission and schistosomiasis cases. PMID:18214167

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

    PubMed

    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.

  13. Contraceptive steroid concentrations in women with early active schistosomiasis: lack of effect of antischistosomal drugs.

    PubMed

    el-Raghy, I; Back, D J; Osman, F; Orme, M L; Fathalla, M

    1986-04-01

    Plasma concentrations of the oral contraceptive steroids (OCS) ethinyloestradiol (EE2) and levonorgestrel (LNG) have been determined in women with early active schistosomiasis and compared to those obtained in healthy volunteers. Steroid concentrations following a single dose of Ovral (500 micrograms LNG, 50 micrograms EE2) or during a multiple dose regimen were unaffected by the disease. There was no significant effect of the antischistosomal drugs praziquantel (40 mg X kg-1) or metrifonate (10 mg X kg-1 X 3 at 2-week intervals) on plasma steroid concentrations. In regular users of OCS, significantly higher concentrations of LNG were observed than in women who received only a single dose. We conclude that there is no pharmacokinetic reason for withholding OCS from patients with early active schistosomiasis who are also receiving either praziquantel or metrifonate.

  14. [Risk assessment and control measures for import of African schistosomiasis into China].

    PubMed

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

    2013-06-01

    The habitats of Biomphalaria straminea, the intermediate host of Schistosoma mansoni, have been found in Hong Kong Special Administrative Region and Shenzhen City of People's Republic of China. Currently, there is a sharp increase in the number of Africa-aid projects and workers moving to Africa, and more and more cases infected with S. mansoni or S. haematobium returning from African countries have been detected in China. The possibility of transmission of African schistosomiasis in Chinese mainland, in the context of global climate warming, has received much attention. This paper illustrates the risk of transmission of African schistosomiasis in China based on biological and epidemiological features, and proposes interventions to tackle the risk.

  15. Schistosomiasis in U.S. Peace Corps volunteers--Malawi, 1992.

    PubMed

    1993-07-30

    Schistosomiasis (i.e., "snail fever" or "bilharzia") is a parasitic infection caused by trematodes (flukes) and is endemic in 74 countries in Africa, South America, the Caribbean, and Asia. U.S. residents who work or travel in these countries may be at risk for schistosomiasis. During 1992, two U.S. Peace Corps volunteers (PCVs) were evacuated from Africa because of Schistosoma hematobium infection of the central nervous system (CNS). Both were exposed to fresh water while vacationing at Cape Maclear, a popular resort area on Lake Malawi (Figure 1), in December 1991. This report summarizes the investigation of these two cases and a follow-up investigation of expatriates residing in Malawi.

  16. 'Independence' Panorama

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Click on the image for 'Independence' Panorama (QTVR)

    This is the Spirit 'Independence' panorama, acquired on martian days, or sols, 536 to 543 (July 6 to 13, 2005), from a position in the 'Columbia Hills' near the summit of 'Husband Hill.' The summit of 'Husband Hill' is the peak near the right side of this panorama and is about 100 meters (328 feet) away from the rover and about 30 meters (98 feet) higher in elevation. The rocky outcrops downhill and on the left side of this mosaic include 'Larry's Lookout' and 'Cumberland Ridge,' which Spirit explored in April, May, and June of 2005.

    The panorama spans 360 degrees and consists of 108 individual images, each acquired with five filters of the rover's panoramic camera. The approximate true color of the mosaic was generated using the camera's 750-, 530-, and 480-nanometer filters. During the 8 martian days, or sols, that it took to acquire this image, the lighting varied considerably, partly because of imaging at different times of sol, and partly because of small sol-to-sol variations in the dustiness of the atmosphere. These slight changes produced some image seams and rock shadows. These seams have been eliminated from the sky portion of the mosaic to better simulate the vista a person standing on Mars would see. However, it is often not possible or practical to smooth out such seams for regions of rock, soil, rover tracks or solar panels. Such is the nature of acquiring and assembling large panoramas from the rovers.

  17. Controversies and challenges in research on urogenital schistosomiasis-associated bladder cancer

    PubMed Central

    Honeycutt, Jared; Hammam, Olfat; Fu, Chi-Ling; Hsieh, Michael H.

    2014-01-01

    Urogenital schistosomiasis, infection with Schistosoma haematobium, is linked to increased risk for the development of bladder cancer, but the importance of various mechanisms responsible for this association remains unclear, in part due to lack of sufficient and appropriate animal models. New advances in the study of this parasite, bladder regenerative processes, and human schistosomal bladder cancers may shed new light on the complex biological processes that connect S. haematobium infection to bladder carcinogenesis. PMID:24913983

  18. Prolonged latent schistosomiasis diagnosed 38 years after infestation in a HIV patient.

    PubMed

    Payet, Barry; Chaumentin, Gilles; Boyer, Michelle; Amaranto, Paula; Lemonon-Meric, Claire; Lucht, Frederic

    2006-01-01

    We report a case of Schistosoma mansoni bilharziasis in a HIV patient 38 y after leaving an endemic region. A viable S. mansoni egg on a liver biopsy sample was diagnostic. Despite severe concomitant immunodeficiency the effective treatment was a single dose of praziquantel. Worms' intravascular longevity and the role of immunodeficiency as a possible factor in eggs retention after such prolonged latent schistosomiasis are discussed.

  19. Silymarin Reduces Profibrogenic Cytokines and Reverses Hepatic Fibrosis in Chronic Murine Schistosomiasis

    PubMed Central

    Mata-Santos, Hílton Antônio; Dutra, Fabianno Ferreira; Rocha, Carolina Carneiro; Lino, Fabiana Gonçalves; Xavier, Fabiola Ramos; Chinalia, Leandro Andrade; Hossy, Bryan Hudson; Castelo-Branco, Morgana Teixeira Lima; Teodoro, Anderson Junger; Paiva, Claudia N.

    2014-01-01

    In chronic schistosomiasis, hepatic fibrosis is linked to the portal hypertension that causes morbidity in Schistosoma mansoni infection. Silymarin (SIL) is a hepatoprotective and antioxidant medicament largely prescribed against liver diseases that has previously been shown to prevent fibrosis during acute murine schistosomiasis. Here we employed silymarin to try to reverse established hepatic fibrosis in chronic schistosomiasis. Silymarin or vehicle was administered to BALB/c mice every 48 h, starting on the 40th (80 days of treatment), 70th (50 days), or 110th (10 days) day postinfection (dpi). All mice were sacrificed and analyzed at 120 dpi. Treatment with silymarin reduced liver weight and granuloma sizes, reduced the increase in alanine aminotransferase and aspartate aminotransferase levels, and reduced the established hepatic fibrosis (assessed by hydroxyproline contents and picrosirius staining). Treatment with silymarin also reduced the levels of interleukin-13 (IL-13) in serum and increased the gamma interferon (IFN-γ)/IL-13 ratio. There was a linear correlation between IL-13 levels in serum and hydroxyproline hepatic content in both infected untreated and SIL-treated mice, with decreased IL-13 levels corresponding to decreased hydroxyproline hepatic contents. Treatment with either SIL or N-acetylcysteine reduced both proliferation of fibroblast cell lines and basal/IL-13-induced production of collagen I, indicating that besides inhibiting IL-13 production during infection, SIL antioxidant properties most likely contribute to inhibition of collagen production downstream of IL-13. These results show that silymarin interferes with fibrogenic cytokines, reduces established fibrosis, and inhibits downstream effects of IL-13 on fibrogenesis, indicating the drug as a safe and cheap treatment to liver fibrotic disease in schistosomiasis. PMID:24449779

  20. Female genital schistosomiasis due to Schistosoma haematobium. Clinical and parasitological findings in women in rural Malawi.

    PubMed

    Kjetland, E F; Poggensee, G; Helling-Giese, G; Richter, J; Sjaastad, A; Chitsulo, L; Kumwenda, N; Gundersen, S G; Krantz, I; Feldmeier, H

    1996-12-30

    A total of 51 women with urinary schistosomiasis haematobium were examined in order to identify diagnostic indicators for female genital schistosomiasis (FGS). Patients were selected at random from the outpatient department of the Mangochi District Hospital, Malawi. The medical histories were recorded according to a pre-designed questionnaire and the women were subjected to a thorough gynaecological examination including colposcopy and photographic documentation of lesions. Microscopy of genital biopsies revealed that 33 of the 51 women had S. haematobium ova in cervix, vagina and/or vulva in addition to the presence of ova in urine. The most sensitive diagnostic procedure was beside microscopic examination of a wet cervix biopsy crushed between two glass slides, which revealed 25 of the 33 genital infections. There was a significant correlation between the size of genital lesions and the number of ova counted per mm2 of crushed tissue. Women with FGS had significantly more tumours in the vulva than women with schistosomiasis limited to the urinary tract. Most of the observed genital pathology could easily be identified by the naked eye, but colposcopic examination yielded valuable additional information like the demonstration of neovascularisation around cervical sandy patches. Few of the symptoms previously regarded as indicators for FGS could be linked to the presence of schistosome ova in genital tissue. Husbands of infertile women with FGS had children with other women significantly more often than husbands of women who only had urinary schistosomiasis. This, together with the finding that the majority of the divorced women had FGS, indicates that the manifestation of this disease may have implications for the marital and sexual life of the affected women.

  1. Lectin Complement Protein Collectin 11 (CL-K1) and Susceptibility to Urinary Schistosomiasis

    PubMed Central

    Antony, Justin S.; Ojurongbe, Olusola; Kremsner, Peter G.; Velavan, Thirumalaisamy P.

    2015-01-01

    Background Urinary Schistosomiasis is a neglected tropical disease endemic in many sub Saharan -African countries. Collectin Kidney 1 (CL-K1, encoded by COLEC11 on chromosome 2p25.3), a member of the vertebrate C-type lectin super family, has recently been identified as pattern-recognition molecule (PRR) of the lectin complement pathway. CL-K1 is preferentially expressed in the kidneys, but also in other organs and it is considered to play a role in host defense to some infectious agents. Schistosome teguments are fucosylated and CL-K1 has, through its collagen-like domain, a high binding affinity to fucose. Methodology/Principal Findings We utilized a Nigerian study group consisting of 167 Schistosoma haematobium infected individuals and 186 matched healthy subjects, and investigated the contribution of CL-K1 deficiency and of COLEC11 polymorphisms to infection phenotype. Higher CL-K1 serum levels were associated with decreased risk of schistosome infection (Pcorr = 0.0004). CL-K1 serum levels were differentially distributed between the COLEC11 genotypes and haplotypes observed. The non-synonymous variant p.R216H was associated with the occurrence of schistosomiasis (OR = 0.44, 95%CI = 0.22–0.72, Pcorr = 0.0004). The reconstructed COLEC11*TCCA haplotypes were associated with higher CL-K1 serum levels (P = 0.002) and with decreased schistosomiasis (OR = 0.38, 95%CI = 0.23–0.63, Pcorr = 0.0001). Conclusions In agreement with findings from our earlier published study, our findings support the observation that CL-K1 and their functional variants may be host factors associated with protection in schistosomiasis and may be a useful marker for further investigations. PMID:25807310

  2. Intestinal schistosomiasis and soil-transmitted helminthiasis in Ugandan schoolchildren: a rapid mapping assessment.

    PubMed

    Standley, Claire J; Adriko, Moses; Alinaitwe, Moses; Kazibwe, Francis; Kabatereine, Narcis B; Stothard, J Russell

    2009-11-01

    Even with a national control programme in place, intestinal schistosomiasis continues to be a major public health problem in school-aged children and other community members in Uganda. This is especially the case in the environments around the Great Lakes, where disease transmission is high, such as Lake Victoria. Moreover, in the most remote areas, some schools might periodically miss large-scale drug administrations owing to inaccessibility. To provide contemporary monitoring and surveillance data, 27 schools along the lakeshore were surveyed with a rapid assessment protocol to determine both prevalence and intensity of Schistosoma mansoni and soil-transmitted helminth infections. In total, 25 (92.6%) of schools were positive for S. mansoni, with an average prevalence across the surveyed children of 42% and average infection intensity of 634 eggs per gram of faeces. Mean prevalence of Trichuris trichiura, Ascaris lumbricoides and hookworm was 12.9%, 9.3% and 2.4%, respectively. Results from questionnaire data revealed a high level of itinerancy among the children, and a total of 38.2% reported to have never received treatment for schistosomiasis, despite 96% living in districts targeted by the national control programme. A birthplace outside of Uganda was a significant predictor for increased risk of schistosomiasis infection (odds ratio (OR) = 9.6), and being resident at a school for less than a year was significantly associated with absence of praziquantel treatment (OR = 0.3). Univariate regression analysis showed a trend of increasing schistosomiasis towards the eastern region of Uganda, while semivariograms of infection prevalence demonstrated a range of spatial autocorrelation of ~78 km. Soil-transmitted helminth infections were more common in the Western region. Our results emphasise how social and demographic variables such as migration may affect epidemiological trends and confound the impact of existing treatment regimes.

  3. Epidemiology of Schistosomiasis among Villagers of the New Halfa Agricultural Scheme, Sudan

    PubMed Central

    AFIFI, Azzam; AHMED, Abdel-Aziz A.; SULIEMAN, Yassir; PENGSAKUL, Theerakamol

    2016-01-01

    Background: Schistosomiasis is one of the major communicable diseases of public health and socioeconomic importance in developing countries. This study assessed the situation of schistosomiasis among villagers of the New Halfa Agricultural Scheme, Sudan. Methods: An epidemiological survey was carried out in three randomly selected residential sites: Village 19, Village 26 and Talat shagrat Camp, from October to December 2013. Feces and urine samples were collected from 2433 individual (1195 male and 1238 female) and examined for schistosomiasis infection. The prevalence and intensity of infection were calculated according to study sites and participants’ sex and age-group. Results: There was no infection with Schistosoma haematobium among the examined individuals, while the overall prevalence of S. mansoni infection was 27.4% and the mean intensity among those infected was 261.1 eggs per gram (epg). A high prevalence and intensity of infection was found among the residents of Talat shagrat Camp, followed by the other two villages. The prevalence of infection among males was 41.4%, and among females was 13.9%. On the other hand, the intensity of infection among females was 293.4 epg and among males 187.6 epg. A high prevalence of infection was found in the age-groups 11–20 years and > 50 years. High intensity of infection was present in the age-groups 31–40 years and > 50 years. Conclusion: The finding of the study shows the need for an integrated control program against schistosomiasis. Mass treatment, provision of adequate clean-water supply and combating the intermediate snail host are suggested. PMID:27095977

  4. Urinary schistosomiasis in the Sahelian region of the Senegal River Basin.

    PubMed

    Chaine, J P; Malek, E A

    1983-09-01

    Two dams are projected for the Senegal River, West Africa, for hydroelectric power, anti-salt intrusion and for provision of a dependable supply of freshwater year-round. This study was to ascertain the geographic distribution of schistosomiasis, its snail hosts and the potential transmission sites before the construction of the two dams. No intestinal schistosomiasis was found in the area investigated, the Sahelian region. Villages in the delta, as well as those situated by the Senegal River in the Middle Valley were found free of urinary schistosomiasis. However, the prevalence of the urinary form averaged 10.4% in villages situated in the higher land away from the river. The transmission sites in these villages are rain-fed, laterite pools which harbor the snail host, Bulinus senegalensis. In one pond the latter was found naturally infected with schistosome cercariae, and there are no bovines or ovines in the area at any time. Other bulinid snails found infected with schistosome cercariae were B. guernei and B. jousseaumei; the latter is probably the snail host of Schistosoma haematobium in one small village in the delta, where a low infection rate was reported by other workers.

  5. Perception of a schistosomiasis control project in rural Kenya by the beneficiaries.

    PubMed

    Katsivo, M N; Muthami, L N; Karama, M; Kingori, F

    1993-10-01

    A schistosomiasis control project was implemented in Mwea Rice Irrigation Scheme in Central Kenya between late 1983 and December 1988 by Kenya Medical Research Institute scientists in collaboration with the National Irrigation Board. The aim of the project was to control schistosomiasis through provision of alternative water sources, bath and laundry units, latrines, chemotherapy and health education. The community participated fully. Five years later in December 1988, 203 household heads were interviewed on their perception of the control project in terms of purpose, project ownership and management, benefits, continuity and their knowledge of schistosomiasis transmission cycle. 61% of the respondents were females and 39% males. 92% of them said that the purpose for the project was to treat, control and prevent bilharzia from spreading, and to promote good health. Slightly over 50% said that the project belonged to them but that they would have liked to be more involved in its management. 74% said that they are able to save time because the facilities are now nearer to them; whilst 79% felt that they were saving money because they did not have to buy drugs since they felt healthier. 99% said that they thought that bilharzia has been controlled, and 82% said that their children looked healthier. 95% said that they could see the project surviving for a long time period suggesting that it was self sustaining and they were willing to start a maintenance of facilities fund. Overall, the community appreciated the social, economic and health benefits derived from the control project.

  6. Current status of schistosomiasis and soil-transmitted helminthiasis in Beyla and Macenta Prefectures, Forest Guinea.

    PubMed

    Hodges, Mary; Koroma, Manso M; Baldé, Mamadou S; Turay, Hamid; Fofanah, Ibrahim; Divall, Mark J; Winkler, Mirko S; Zhang, Yaobi

    2011-11-01

    A cross-sectional survey was undertaken in children aged 9-14 years in Beyla and Macenta Prefectures, Forest Guinea. Stool samples were examined by Kato-Katz and urine samples were examined by the centrifugation method. The overall prevalence and intensity of infection was 66.2% and 462.4 eggs per gram of faeces (epg) for Schistosoma mansoni, 21.0% and 17.8 eggs per 10ml of urine for S. haematobium, 51.2% and 507.5 epg for hookworm, 8.1% and 89.1 epg for Ascaris lumbricoides and 2.4% and 16.7 epg for Trichuris trichiura. The overall prevalence of schistosomiasis (S. mansoni and/or S. haematobium) was 70.7%. The prevalence of schistosomiasis was similar to those reported in the 1990s in the region; however, the prevalence of soil-transmitted helminths has since fallen. These findings illustrate the need for schistosomiasis control in Guinea.

  7. Questionnaires for rapid screening of schistosomiasis in sub-Saharan Africa.

    PubMed Central

    Lengeler, Christian; Utzinger, Jürg; Tanner, Marcel

    2002-01-01

    New initiatives are aiming to reduce the global burden of schistosomiasis, mainly through the large-scale application of chemotherapy. To target chemotherapy effectively, rapid assessment procedures are needed for identifying high-risk communities that are foci for the disease. In this review, we examine the development and validation of simple school questionnaires for screening communities for Schistosoma haematobium and S. mansoni rapidly and inexpensively. The focus is on sub-Saharan Africa, where 85% of the current schistosomiasis burden is concentrated. For more than a decade, the questionnaire approach has been validated in 10 countries, with 133 880 children interviewed in 1282 schools, and with 54 996 children examined for S. haematobium. The questionnaires were well accepted, highly reliable, and of low cost. The success of the questionnaires is explained by the fact that S. haematobium infections were easily perceived through the presence of blood in urine. Evidence from 48 258 children interviewed in 545 schools indicated that reported blood in stools and bloody diarrhoea are valuable indicators for community diagnosis of S. mansoni. However, the diagnostic performance of the questionnaires for S. mansoni was weaker than for S. haematobium, and although these results are encouraging, the questionnaires need additional validation. Recently, questionnaires were extended from community to individual diagnosis and showed considerable promise. Questionnaires are now available for promptly defining the magnitude of schistosomiasis in a large area, which will allow limited resources for morbidity control to be allocated optimally. PMID:11984610

  8. Urinary Schistosomiasis in Urban and Semi-Urban Communities in South-Eastern Nigeria

    PubMed Central

    OKEKE, Ogochukwu Caroline; UBACHUKWU, Patience Obiageli

    2013-01-01

    Background In view of the massive rural-to-urban migration in Nigeria, investigations on transmission of urinary schistosomiasis were carried out in urban and semi-urban communities in Nike Lake area of Enugu State, Nigeria. Methods Urine samples of school children were tested for micro-haematuria using reagent strips followed by microscopic examination for Schistosoma haematobium eggs. Water contact sites were also identified and sampled for snails. Results The overall prevalence of S. haematobium eggs in school children was 4.64%. The mean intensity of infection was 1.14 ± 0.41 eggs/10ml urine. Males had insignificantly higher prevalence and intensity of S. haematobium infection than females. The youngest age group (4-7 years) had no infection. The prevalence of micro-haematuria (6.2%) was higher than that of microscopy, and this correlated positively with prevalence (r = 0.65, P < 0.01) and intensity (r = 0.50, P < 0.01) of the infection. Potential intermediate host of human shistosome collected were: Bulinus globosus, B. senegalensis and Biomphalaria pfeifferi. However, only B. globosus shed cercariae of S. haematobium, with a snail infection rate of 0.73%. Transmission was in the dry season coinciding with the drying of wells. Conclusion The results revealed that urinary schistosomiasis is prevalent, and that B. globosus and not B. truncatus as previously reported is the main intermediate host of urinary schistosomiasis in this part of Enugu State. PMID:24454442

  9. Schistosomiasis control and the health system in P.R. China

    PubMed Central

    2012-01-01

    Over the last sixty years advances have been made in the control of schistosomiasis in P.R. China. There are, however, difficult challenges still to be met. This paper looks at the extent to which the health system offers a positive environment for the control of the disease. It starts by tracing three phases in schistosomiasis control: disease elimination strategy through snail control (1950s-early 1980s); morbidity control strategy based on chemotherapy (mid 1980s to 2003); integrated control strategy (2004+). Each one of these phases took place in distinct policy-making environments. The paper partly draws on these phases to set out five issues of disease control and discusses them in the context of the health system and its recent trends. These cover the policy-making process, intersectoral action for health, equity and access to health services, funding for public goods and externalities, and strengthening resource management and planning. These issues form the basis of an agenda for integrating research and capacity strengthening in the Chinese health system with a view to creating a more positive enabling environment for schistosomiasis control. In so doing it is important to emphasize the role and integrity of the public sector against its commercialization, the underlying value of equity, a systems wide perspective, and the role of advocacy. PMID:23849320

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

    PubMed

    Sombetzki, Martina; Koslowski, Nicole; Doss, Sandra; Loebermann, Micha; Trauner, Michael; Reisinger, Emil C; Sauer, Martin

    2016-01-01

    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.

  11. Multi-host transmission dynamics of schistosomiasis and its optimal control.

    PubMed

    Ding, Chunxiao; Qiu, Zhipeng; Zhu, Huaiping

    2015-10-01

    In this paper we formulate a dynamical model to study the transmission dynamics of schistosomiasis in humans and snails. We also incorporate bovines in the model to study their impact on transmission and controlling the spread of Schistosoma japonicum in humans in China. The dynamics of the model is rigorously analyzed by using the theory of dynamical systems. The theoretical results show that the disease free equilibrium is globally asymptotically stable if R0 < 1, and if R0 > 1 the system has only one positive equilibrium. The local stability of the unique positive equilibrium is investigated and sufficient conditions are also provided for the global stability of the positive equilibrium. The optimal control theory are further applied to the model to study the corresponding optimal control problem. Both analytical and numerical results suggest that: (a) the infected bovines play an important role in the spread of schistosomiasis among humans, and killing the infected bovines will be useful to prevent transmission of schistosomiasis among humans; (b) optimal control strategy performs better than the constant controls in reducing the prevalence of the infected human and the cost for implementing optimal control is much less than that for constant controls; and

  12. The Estrada Real project and endemic diseases: the case of schistosomiasis, geoprocessing and tourism.

    PubMed

    Carvalho, Omar S; Scholte, Ronaldo G C; Guimarães, Ricardo J P S; Freitas, Corina C; Drummond, Sandra C; Amaral, Ronaldo S; Dutra, Luciano V; Oliveira, Guilherme; Massara, Cristiano L; Enk, Martin J

    2010-07-01

    Geographical Information System (GIS) is a tool that has recently been applied to better understand spatial disease distributions. Using meteorological, social, sanitation, mollusc distribution data and remote sensing variables, this study aimed to further develop the GIS technology by creating a model for the spatial distribution of schistosomiasis and to apply this model to an area with rural tourism in the Brazilian state of Minas Gerais (MG). The Estrada Real, covering about 1,400 km, is the largest and most important Brazilian tourism project, involving 163 cities in MG with different schistosomiasis prevalence rates. The model with three variables showed a R(2) = 0.34, with a standard deviation of risk estimated adequate for public health needs. The main variables selected for modelling were summer vegetation, summer minimal temperature and winter minimal temperature. The results confirmed the importance of Remote Sensing data and the valuable contribution of GIS in identifying priority areas for intervention in tourism regions which are endemic to schistosomiasis.

  13. Schistosomiasis in the People's Republic of China: Prospects and Challenges for the 21st Century

    PubMed Central

    Ross, Allen G. P.; Sleigh, Adrian C.; Li, Yuesheng; Davis, George M.; Williams, Gail M.; Jiang, Zheng; Feng, Zheng; McManus, Donald P.

    2001-01-01

    Schistosomiasis japonica is a serious communicable disease and a major disease risk for more than 30 million people living in the tropical and subtropical zones of China. Infection remains a major public health concern despite 45 years of intensive control efforts. It is estimated that 865,000 people and 100,250 bovines are today infected in the provinces where the disease is endemic, and its transmission continues. Unlike the other schistosome species known to infect humans, the oriental schistosome, Schistosoma japonicum, is a true zoonotic organism, with a range of mammalian reservoirs, making control efforts extremely difficult. Clinical features of schistosomiasis range from fever, headache, and lethargy to severe fibro-obstructive pathology leading to portal hypertension, ascites, and hepatosplenomegaly, which can cause premature death. Infected children are stunted and have cognitive defects impairing memory and learning ability. Current control programs are heavily based on community chemotherapy with a single dose of the drug praziquantel, but vaccines (for use in bovines and humans) in combination with other control strategies are needed to make elimination of the disease possible. In this article, we provide an overview of the biology, epidemiology, clinical features, and prospects for control of oriental schistosomiasis in the People's Republic of China. PMID:11292639

  14. A Novel Bacterial Pathogen of Biomphalaria glabrata: A Potential Weapon for Schistosomiasis Control?

    PubMed Central

    Duval, David; Galinier, Richard; Mouahid, Gabriel; Toulza, Eve; Allienne, Jean François; Portela, Julien; Calvayrac, Christophe; Rognon, Anne; Arancibia, Nathalie; Mitta, Guillaume; Théron, André; Gourbal, Benjamin

    2015-01-01

    Background Schistosomiasis is the second-most widespread tropical parasitic disease after malaria. Various research strategies and treatment programs for achieving the objective of eradicating schistosomiasis within a decade have been recommended and supported by the World Health Organization. One of these approaches is based on the control of snail vectors in endemic areas. Previous field studies have shown that competitor or predator introduction can reduce snail numbers, but no systematic investigation has ever been conducted to identify snail microbial pathogens and evaluate their molluscicidal effects. Methodology/Principal findings In populations of Biomphalaria glabrata snails experiencing high mortalities, white nodules were visible on snail bodies. Infectious agents were isolated from such nodules. Only one type of bacteria, identified as a new species of Paenibacillus named Candidatus Paenibacillus glabratella, was found, and was shown to be closely related to P. alvei through 16S and Rpob DNA analysis. Histopathological examination showed extensive bacterial infiltration leading to overall tissue disorganization. Exposure of healthy snails to Paenibacillus-infected snails caused massive mortality. Moreover, eggs laid by infected snails were also infected, decreasing hatching but without apparent effects on spawning. Embryonic lethality was correlated with the presence of pathogenic bacteria in eggs. Conclusions/Significance This is the first account of a novel Paenibacillus strain, Ca. Paenibacillus glabratella, as a snail microbial pathogen. Since this strain affects both adult and embryonic stages and causes significant mortality, it may hold promise as a biocontrol agent to limit schistosomiasis transmission in the field. PMID:25719489

  15. Genital Schistosomiasis: A Report on Two Cases of Ovarian Carcinomas Containing Viable Eggs of Schistosoma mansoni

    PubMed Central

    Gonçalves Amorim, Andressa; Alves Barbosa Pagio, Fernanda; Neves Ferreira, Rodrigo; Chambô Filho, Antônio

    2014-01-01

    Schistosomiasis is a parasitic infection that is highly prevalent worldwide, with a variety of species being responsible for causing the disease. In Brazil, however, the only identified species is Schistosoma mansoni. The adult parasites inhabit the blood vessels of the hepatic portal system of the main host. The disease may range from being asymptomatic to provoking liver damage or portal hypertension. Furthermore, ectopic schistosomiasis may develop, and several hypotheses have been raised to explain the occurrence of the disease. This paper describes two cases, one in a 39-year-old woman and the other in a 47-year-old woman. Both had similar symptoms of pain and abdominal distension caused by a large abdominal/pelvic mass. Histopathology of the ovary showed a mucinous cystadenocarcinoma of the intestinal type in the first patient and a papillary serous carcinoma in the second, with both tumors containing viable eggs of Schistosoma mansoni. The neoplasms probably serve as a migratory route for the adult parasites and the embolization of eggs. Nevertheless, there is insufficient evidence to confirm the malignization of a benign lesion due to the presence of Schistosoma mansoni. Few cases have been reported in the international literature on the association between ovarian schistosomiasis and neoplasms. PMID:25587473

  16. A review of schistosomiasis in immigrants in Western Australia, demonstrating the unusual longevity of Schistosoma mansoni.

    PubMed

    Harris, A R; Russell, R J; Charters, A D

    1984-01-01

    Sixteen patients with imported schistosomiasis in Western Australia, a non-endemic area, are recorded. Ten with Schistosoma mansoni had lived there for over 20 years, three for over 31 years and two for more than 32 years. No record of a life span of 31 years for S. mansoni can be found in the literature. The principal symptomatology in three patients with S. mansoni was hypersplenism. Four patients with S. mansoni were asymptomatic. Ten had eosinophil counts greater than 0.3 X 10(9)/1 and one who showed no peripheral eosinophilia had numerous eosinophil myelocytes in his bone marrow. A diagnosis of schistosomiasis was initially suspected in five cases by respective discovery of eosinophil myelocytes in the bone marrow, radiological evidence of calcification of the bladder wall and beading of both ureters, cytoscopic findings of sandy patches in the bladder, discovery of ova in the wall of a fallopian tube at ectopic gestation and the presence of ova and an adult worm in a uterine leiomyoma. The risk of infection of the Ord River Dam is greater for S. japonicum than for the African species. An epidemiological feature of this series is that refugees from Poland contracted schistosomiasis (S. mansoni) in refugee camps in East Africa and then migrated to Western Australia between 1950 and 1953.

  17. Big-data-driven modeling unveils country-wide drivers of endemic schistosomiasis.

    PubMed

    Mari, Lorenzo; Gatto, Marino; Ciddio, Manuela; Dia, Elhadji D; Sokolow, Susanne H; De Leo, Giulio A; Casagrandi, Renato

    2017-03-28

    Schistosomiasis is a parasitic infection that is widespread in sub-Saharan Africa, where it represents a major health problem. We study the drivers of its geographical distribution in Senegal via a spatially explicit network model accounting for epidemiological dynamics driven by local socioeconomic and environmental conditions, and human mobility. The model is parameterized by tapping several available geodatabases and a large dataset of mobile phone traces. It reliably reproduces the observed spatial patterns of regional schistosomiasis prevalence throughout the country, provided that spatial heterogeneity and human mobility are suitably accounted for. Specifically, a fine-grained description of the socioeconomic and environmental heterogeneities involved in local disease transmission is crucial to capturing the spatial variability of disease prevalence, while the inclusion of human mobility significantly improves the explanatory power of the model. Concerning human movement, we find that moderate mobility may reduce disease prevalence, whereas either high or low mobility may result in increased prevalence of infection. The effects of control strategies based on exposure and contamination reduction via improved access to safe water or educational campaigns are also analyzed. To our knowledge, this represents the first application of an integrative schistosomiasis transmission model at a whole-country scale.

  18. Diagnosis of Schistosomiasis by Reagent Strip Test for Detection of Circulating Cathodic Antigen

    PubMed Central

    van Dam, G. J.; Wichers, J. H.; Ferreira, T. M. Falcao; Ghati, D.; van Amerongen, A.; Deelder, A. M.

    2004-01-01

    A newly developed reagent strip assay for the diagnosis of schistosomiasis based on parasite antigen detection in urine of infected individuals was evaluated. The test uses the principle of lateral flow through a nitrocellulose strip of the sample mixed with a colloidal carbon conjugate of a monoclonal antibody specific for Schistosoma circulating cathodic antigen (CCA). The strip assay to diagnose a group of highly infected schoolchildren in Mwanza, Tanzania, demonstrated a high sensitivity and association with the intensity of infection as measured both by egg counts, and by circulating anodic antigen and CCA levels determined by enzyme-linked immunosorbent assay. A specificity of ca. 90% was shown in a group of schistosome-negative schoolchildren from Tarime, Tanzania, an area where schistosomiasis is not endemic. The test is easy to perform and requires no technical equipment or special training. The stability of the strips and the conjugate in the dry format lasts for at least 3 months at ambient temperature in sealed packages, making it suitable for transport and use in areas where schistosomiasis is endemic. This assay can easily be developed to an end-user format. PMID:15583265

  19. Community Knowledge, Perceptions, and Practices Associated with Urogenital Schistosomiasis among School-Aged Children in Zanzibar, United Republic of Tanzania

    PubMed Central

    Person, Bobbie; Ali, Said M.; A’Kadir, Faiza M.; Ali, Jamal N.; Mohammed, Ulfat A.; Mohammed, Khalfan A.; Rollinson, David; Knopp, Stefanie

    2016-01-01

    Background On the Zanzibar islands, United Republic of Tanzania, elimination of urogenital schistosomiasis is strived for in the coming years. This qualitative study aimed to better understand community knowledge, perceptions, and practices associated with schistosomiasis among school-aged children on Unguja and Pemba islands, in order to inform the development of behavior change interventions contributing to eliminate urogenital schistosomiasis. Methodology In 2011, we conducted 35 children’s discussion groups, 41 in-depth interviews with parents and teachers, and 5 focus group discussions with community members in Zanzibar. Using a modified-grounded theory approach, we transcribed and coded the narrative data followed by thematic analysis of the emergent themes. Principal Findings Urogenital schistosomiasis is a common experience among children in Zanzibar and typically considered a boys’ disease. Children engage in multiple high-risk behaviors for acquiring schistosomiasis because of poor knowledge on disease transmission, lack of understanding on severity of disease-associated consequences, and lack of alternative options for water related activities of daily living and recreational play. Local primary school teachers had little to no training about the disease and no teaching tools or materials for students. Conclusions/Significance Conducting activities in open natural freshwater contaminated by S. haematobium larvae compromises the health of school-aged children in Zanzibar. The perception of urogenital schistosomiasis as a minor illness rather than a serious threat to a child’s well-being contributes to the spread of disease. Understanding community perceptions of disease along with the barriers and facilitators to risk reduction behaviors among children can inform health promotion activities, campaigns, and programs for the prevention, control, and elimination of urogenital schistosomiasis in Zanzibar. PMID:27399310

  20. Spatio-temporal modeling with GIS and remote sensing for schistosomiasis control in Sichuan, China

    NASA Astrophysics Data System (ADS)

    Xu, Bing

    Schistosomiasis is a water-borne parasitic disease endemic in tropical and subtropical areas. Its transmission requires certain kind of snail as the intermediate host. Some efforts have been made to mapping snail habitats with remote sensing and schistosomiasis transmission modeling. However, the modeling is limited to isolated residential groups and does not include spatial interaction among those groups. Remotely sensed data are only used in snail habitat classification, not in estimation of snail abundance that is an important parameter in schistosomiasis transmission modeling. This research overcomes the above two problems using innovative geographic information system (GIS) and remote sensing technology. A mountainous environment near Xichang, China, is chosen as the test site. Environmental and epidemiological data are stored in a GIS to support modeling. Snail abundance is estimated from land-cover and land-use fractions derived from high spatial resolution IKONOS satellite data. Spatial interaction is determined in consideration of neighborhoods, group areas, relative slopes among groups, and natural barriers. Land-cover and land-use information extracted from 4 m high resolution IKONOS data is used as reference in scaling up to the regional level. The scale-up is done with coarser resolution satellite data including Landsat Thematic Mapper (TM), EO-1 Advanced Land Imager (ALI) and Hyperion data all at 30 m resolution. Snail abundance is estimated by regressing snail survey data with land-cover and land-use fractions. An R2 of 0.87 is obtained between the average snail density predicted and that surveyed at the group level. With such a model, a snail density map is generated for all residential groups in the study area. A spatio-temporal model of schistosomiasis transmission is finally built to incorporate the spatial interaction caused by miracidia and cercaria migration. Comparing the model results with and without spatial interaction has revealed a

  1. A case control study on the structural equation model of the mechanism of coagulation and fibrinolysis imbalance in chronic schistosomiasis.

    PubMed

    Le, Aiping; Zhang, Lunli; Liu, Wei; Li, Xiaopeng; Ren, Jianwei; Ning, An

    2017-02-01

    A structural equation model was used for verification with chronic schistosomiasis to investigate the coagulation-anticoagulation system imbalance and to deduce the mechanism of D-dimer (D-D) level elevation in patients with advanced schistosome hepatic disease. We detected the plasma levels of tissue-type fiber plasminogen activator (tPA), urokinase type plasminogen activator (uPA), plasmin-antiplasmin complex (PAP), plasminogen (PLG), antithrombin (AT), plasminogen activator inhibitor 1 (PAI1), D-D, factor VIII: C (FVIII:C), antithrombin-III (AT-III), PLG, protein S (PS), and protein C (PC) in the healthy people as control (69), patients with chronic schistosomiasis (150) or advanced chronic schistosomiasis (90). FVIII, PAP, D-D, tPA, and uPA plasma levels were significantly higher in the chronic group than in the control group and were also significantly higher in the advanced group. However, AT-III, PC, PS, AT, PLG, and PAI1 plasma levels in the advanced and chronic groups were significantly lower than those in the control group. With progression of disease in patients with schistosomiasis japonica, a hypercoagulable state is induced by the coagulation-anticoagulation imbalance, eventually leading to patients with high levels of D-D. Furthermore, we established a structural equation model path of a "chronic schistosomiasis disease stage-(coagulation-anticoagulation-fibrinolysis)-D-D." By using analysis of moment structures (AMOS), it was shown that the chronic schistosomiasis stage was positively related to factor VIII and had negative correlation with AT-III; a good positive correlation with PAP, tPA, and uPA; and a good negative correlation with PLG and PAI1. In addition, our results show that the path coefficient of anticoagulation-fibrinolysis system to the chronic stage of schistosomiasis or D-D levels was significantly higher than that of the coagulation system. In conclusion, the coagulation and fibrinolysis imbalance in patients with chronic

  2. A case control study on the structural equation model of the mechanism of coagulation and fibrinolysis imbalance in chronic schistosomiasis

    PubMed Central

    Le, Aiping; Zhang, Lunli; Liu, Wei; Li, Xiaopeng; Ren, Jianwei; Ning, An

    2017-01-01

    Abstract A structural equation model was used for verification with chronic schistosomiasis to investigate the coagulation–anticoagulation system imbalance and to deduce the mechanism of D-dimer (D-D) level elevation in patients with advanced schistosome hepatic disease. We detected the plasma levels of tissue-type fiber plasminogen activator (tPA), urokinase type plasminogen activator (uPA), plasmin-antiplasmin complex (PAP), plasminogen (PLG), antithrombin (AT), plasminogen activator inhibitor 1 (PAI1), D-D, factor VIII: C (FVIII:C), antithrombin-III (AT-III), PLG, protein S (PS), and protein C (PC) in the healthy people as control (69), patients with chronic schistosomiasis (150) or advanced chronic schistosomiasis (90). FVIII, PAP, D-D, tPA, and uPA plasma levels were significantly higher in the chronic group than in the control group and were also significantly higher in the advanced group. However, AT-III, PC, PS, AT, PLG, and PAI1 plasma levels in the advanced and chronic groups were significantly lower than those in the control group. With progression of disease in patients with schistosomiasis japonica, a hypercoagulable state is induced by the coagulation–anticoagulation imbalance, eventually leading to patients with high levels of D-D. Furthermore, we established a structural equation model path of a “chronic schistosomiasis disease stage–(coagulation–anticoagulation–fibrinolysis)–D-D.” By using analysis of moment structures (AMOS), it was shown that the chronic schistosomiasis stage was positively related to factor VIII and had negative correlation with AT-III; a good positive correlation with PAP, tPA, and uPA; and a good negative correlation with PLG and PAI1. In addition, our results show that the path coefficient of anticoagulation–fibrinolysis system to the chronic stage of schistosomiasis or D-D levels was significantly higher than that of the coagulation system. In conclusion, the coagulation and fibrinolysis imbalance in

  3. Moderate and high endemicity of schistosomiasis is a predictor of the endemicity of soil-transmitted helminthiasis: a systematic review.

    PubMed

    Yajima, A; Gabrielli, A F; Montresor, A; Engels, D

    2011-02-01

    The authors conducted a systematic literature review with the following aims: to investigate how frequently soil-transmitted helminthiasis (STH) infections are endemic where schistosomiasis is present; and to assess the correlation between the risk level of schistosomiasis and that of STH. Among 155 sites on which data were collected and analyzed, schistosomiasis was present in 130, all of which were also co-endemic for STH, whereas 25 sites were endemic only for STH. Ninety percent (117 out of 130) of the areas eligible for preventive chemotherapy (PC) against schistosomiasis are also eligible for PC against STH. This fact provides managers of control programmes with the operationally important indication that use of available information on endemicity of schistosomiasis is a valid tool to predict the presence of STH in the same geographical area and to estimate the need of PC for STH. The implementation of this tool is expected to save financial and human resources and help accelerate the scale-up of PC throughout the world.

  4. Multi-host model and threshold of intermediate host Oncomelania snail density for eliminating schistosomiasis transmission in China

    PubMed Central

    Zhou, Yi-Biao; Chen, Yue; Liang, Song; Song, Xiu-Xia; Chen, Geng-Xin; He, Zhong; Cai, Bin; Yihuo, Wu-Li; He, Zong-Gui; Jiang, Qing-Wu

    2016-01-01

    Schistosomiasis remains a serious public health issue in many tropical countries, with more than 700 million people at risk of infection. In China, a national integrated control strategy, aiming at blocking its transmission, has been carried out throughout endemic areas since 2005. A longitudinal study was conducted to determine the effects of different intervention measures on the transmission dynamics of S. japonicum in three study areas and the data were analyzed using a multi-host model. The multi-host model was also used to estimate the threshold of Oncomelania snail density for interrupting schistosomiasis transmission based on the longitudinal data as well as data from the national surveillance system for schistosomiasis. The data showed a continuous decline in the risk of human infection and the multi-host model fit the data well. The 25th, 50th and 75th percentiles, and the mean of estimated thresholds of Oncomelania snail density below which the schistosomiasis transmission cannot be sustained were 0.006, 0.009, 0.028 and 0.020 snails/0.11 m2, respectively. The study results could help develop specific strategies of schistosomiasis control and elimination tailored to the local situation for each endemic area. PMID:27535177

  5. Accessibility to and utilisation of schistosomiasis-related health services in a rural area of state of Minas Gerais, Brazil.

    PubMed

    Reis, Dener Carlos dos; Kloos, Helmut; King, Charles; Quites, Humberto Ferreira Oliveira; Matoso, Leonardo Ferreira; Coelho, Kellen Rosa; Gazzinelli, Andrea

    2010-07-01

    The objective of the present paper was to compare accessibility and utilisation of schistosomiasis diagnostic and treatment services in a small village and the surrounding rural area in northern part of the state of Minas Gerais Brazil. The study included 1,228 individuals: 935 central village residents and 293 rural residents of São Pedro do Jequitinhonha. Schistosoma mansoni infection rates were significantly higher in the central village than in the rural area during a survey in 2007 (44.3% and 23.5%, respectively) and during the 2002 schistosomiasis case-finding campaign (33.1% and 26.5%, respectively) (p < 0.001). However, during the 2002-2006 period, only 23.7% of the villagers and 27% of the rural residents obtained tests on their own from health centres, hospitals and private clinics in various nearby towns. In 2007, 63% of the villagers and 70.5% of the rural residents reported never having received treatment for schistosomiasis. This paper reveals considerable variation in the accessibility and utilisation of schistosomiasis-related health services between the central village and the rural area. A combination of low utilisation rates between 2002-2006 and persistently high S. mansoni infection rates suggest that the schistosomiasis control program must be more rapidly incorporated into the primary health services.

  6. SCHISTOSOMIASIS IN NAG HAMMADY CITY, RELATIONSHIP BETWEEN INFECTION AND ANEMIA AMONG CHILDREN AND YOUTH, QENA GOVERNORATE, EGYPT.

    PubMed

    Abd Ellah, Osama H; Zaytoun, Sameh Sh; Ahmed, Ahmed E; Hussein, Abdel-Nasser A; Ahmed, Amal M

    2015-08-01

    The highest prevalence of schistosomiasis is usually found in school-age children and youth, where it represents the main cause of iron deficiency anemia. Study was done on 859 patients; their age from 5-18 years old at Nag Hammady at the period from July 2013 to July 2014 all of them had subjective history of contact or swimming in water canals. Urine was examined for urinary schistosomiasis by concentration and positive cases were subjected to urine analysis by Nucleopore filtration technique, S. haematobium was 30.96%, while stool samples were macroscopically examined mainly for enterobiasis and gravid segments and then were microscopically examined as stained direct smear and by sedimentation and Kato-Katz techniques. The intestinal parasites other than intestinal schistosomiasis were not encountered and the pure S. mansoni was 0.69% of examined patients. The overall pure schistosomiasis was 31.66%. Iron deficiency anemia was 27.7% in non-infected cases and in schistosomiasis patients iron deficiency anemia were found in 43.38% with statistically significant (P value=0.001).

  7. New uses for old drugs: the tale of artemisinin derivatives in the elimination of schistosomiasis japonica in China.

    PubMed

    Liu, Yi-Xin; Wu, Wei; Liang, Yue-Jin; Jie, Zu-Liang; Wang, Hui; Wang, Wei; Huang, Yi-Xin

    2014-09-19

    Artemisinin (qinghaosu), extracted from the Chinese herb Artemisia annua L. in 1972, and its three major derivatives--artemether, artesunate and dihydroartemisinin--were firstly identified as antimalarials and found active against all species of the malaria parasite. Since the early 1980s, artemisinin and its derivatives have been found efficacious against Schistosoma spp., notably larval parasites, and artemisinin derivatives have played a critical role in the prevention and treatment of human schistosomiasis in China. Currently, China is moving towards the progress of schistosomiasis elimination. However, the potential development of praziquantel resistance may pose a great threat to the progress of elimination of schistosomiasis japonica in China. Fortunately, these three major artemisinin derivatives also exhibit actions against adult parasites, and reduced sensitivity to artemether, artesunate and dihydroartemisinin has been detected in praziquantel-resistant S. japonicum. In this review, we describe the application of artemisinin derivatives in the prevention and treatment of schistosomiasis japonica in China, so as to provide tools for the global agenda of schistosomiasis elimination. In addition to antimalarial and antischistosomal actions, they also show activities against other parasites and multiple cancers. Artemisinin derivatives, as old drugs identified firstly as antimalarials, continue to create new stories.

  8. Clinical Report: Schistosomiasis Exposure in U.S. Service Personnel During Whitewater Rafting on the Nile River in Jinja, Uganda.

    PubMed

    Maluil, Samuel; Stevens, Rom A

    2016-11-01

    Schistosomiasis is a known risk after exposure to freshwater in tropical parts of the world. In March 2014, 28 off-duty U.S. service members went on a water adventure in the Nile River in Jinja, Uganda. In April 2014, 10 of the 28 service members returned for a second water adventure. Twelve weeks after freshwater exposure, schistosomiasis enzyme-linked immunosorbent assay testing was performed. Twenty-five percent had elevated Schistosomiasis mansoni immunoglobulin G (7 positive of 28 exposed); all had negative pre-exposure serology. The serology-positive service members were treated with oral praziquantel 60 mg/kg in divided doses. Our report is the first schistosomiasis report among U.S. service members deployed to Africa since World War II. The absence of reports among U.S. service members and several reports among deployed foreign military units and tourists in sub-Saharan Africa suggest a lack of postexposure testing. We recommend schistosomiasis testing of prior and future U.S. military units deployed to sub-Saharan Africa with fresh water exposure. Unit commanders and medical personnel should discourage unnecessary fresh water contact in sub-Saharan Africa.

  9. Are health education interventions effective for the control and prevention of urogenital schistosomiasis in sub-Saharan Africa? A systematic review.

    PubMed

    Price, Amy; Verma, Arpana; Welfare, William

    2015-04-01

    An estimated 129 million people are infected with urogenital schistosomiasis in sub-Saharan Africa. Current control recommendations endorse mass administration of praziquantel. Health education is an important component of effective schistosomiasis prevention and control, but there has been limited research on its effectiveness. This paper reviews the effectiveness of health education as an intervention in the prevention and control of urogenital schistosomiasis in sub-Saharan Africa. The outcomes of interest were prevalence, incidence or transmission of schistosomiasis, behaviour change associated with infection, or changes in knowledge of the disease. The findings from this review suggest that health education has a beneficial impact on knowledge and understanding of schistosomiasis within the target groups. However, further research is needed due to the poor quality of the included studies.

  10. Access to, and use of, water by populations living in a schistosomiasis and fascioliasis co-endemic area of northern Côte d'Ivoire.

    PubMed

    Krauth, Stefanie J; Musard, Capucine; Traoré, Seïdinan I; Zinsstag, Jakob; Achi, Louise Y; N'Goran, Eliézer K; Utzinger, Jürg

    2015-09-01

    Water is an essential element of life, but it can also be a source of disease. Apart from direct consumption of unsafe water, direct contact and indirect consumption puts people at risk of many different types of pathogens. Employing a mixed methods approach, consisting of questionnaires and direct observations, we assessed access to, and use of, different water sources by the participants of the district des Savanes in northern Côte d'Ivoire. The use of water sources was put in relation to the potential risk of acquiring schistosomiasis and fascioliasis. Overall, 489 people aged 8 to 82 years participated. While all participants had access to safe water, 63% were in direct contact with unimproved water and 31% directly consumed unsafe water. More than a third of the people who otherwise reported using only improved water for all activities came in contact with unimproved water through crossing open water when going to their workplace, school or other destinations. Self-reported blood in urine - a marker for Schistosoma haematobium with reasonable sensitivity and specificity - was reported by 6% (n=30), self-reported blood in stool - an unspecific marker for Schistosoma mansoni - was reported by 7% (n=35), while blood co-occurring in both urine and stool was reported by another 10% (n=48) of participants. Accessing unimproved water for any activity (including crossing) was associated with higher odds of reporting blood in urine and/or blood in stool (odds ratio: 1.90; 95% confidence interval: 1.07-3.36). Our results have important rami-fications for intervention programmes targeting neglected tropical diseases, and emphasize the need for a wider supply of safe water to rural populations, since the water supply at the workplace needs to be considered as well next to the water supply at home. Crossing of open water sources is an important risk factor for sustained transmission of schistosomiasis.

  11. Coinfection with the intestinal nematode Heligmosomoides polygyrus markedly reduces hepatic egg-induced immunopathology and proinflammatory cytokines in mouse models of severe schistosomiasis.

    PubMed

    Bazzone, Lindsey E; Smith, Patrick M; Rutitzky, Laura I; Shainheit, Mara G; Urban, Joseph F; Setiawan, Tommy; Blum, Arthur M; Weinstock, Joel V; Stadecker, Miguel J

    2008-11-01

    Infection with the trematode helminth Schistosoma mansoni results in a parasite egg-induced, CD4 T-cell-mediated, hepatointestinal granulomatous and fibrosing inflammation that varies greatly in severity, with a higher frequency of milder forms typically occurring in regions where the disease is endemic. One possible explanation for this is that in these regions the degree of inflammation is lessened by widespread concurrent infection with gastrointestinal nematodes. We tested this hypothesis by establishing a murine coinfection model in which mice were infected with the intestinal nematode parasite Heligmosomoides polygyrus prior to infection with S. mansoni. In CBA mice that naturally display a severe form of schistosomiasis, preinfection with H. polygyrus resulted in a marked reduction in schistosome egg-induced hepatic immunopathology, which was associated with significant decreases in the levels of interleukin-17 (IL-17), gamma interferon, tumor necrosis factor alpha, IL-23, IL-6, and IL-1beta and with increases in the levels of IL-4, IL-5, IL-10, and transforming growth factor beta in mesenteric lymph node cells, purified CD4 T cells, and isolated liver granuloma cells. There also were increases in liver Ym1 and forkhead box P3 transcription factor expression. In another model of high-pathology schistosomiasis induced in C57BL/6 mice by immunization with schistosome egg antigens in complete Freund's adjuvant, coinfection with the nematodes also resulted in a marked inhibition of hepatic immunopathology accompanied by similar shifts in cytokine production. These findings demonstrate that intestinal nematodes prevent Th1- and Th17-cell-mediated inflammation by promoting a strong Th2-polarized environment associated with increases in the levels of alternatively activated macrophages and T regulatory cells, which result in significant amelioration of schistosome-induced immunopathology.

  12. Repetition Blindness Occurs in Nonwords

    ERIC Educational Resources Information Center

    Harris, Catherine L.; Morris, Alison L.

    2004-01-01

    Theorists have predicted that repetition blindness (RB) should be absent for nonwords because they do not activate preexisting mental types. The authors hypothesized that RB would be observed for nonwords because RB can occur at a sublexical level. Four experiments showed that RB is observed for word-nonword pairs (noon noof), orthographically…

  13. Increasing the reach: Involving local Muslim religious teachers in a behavioral intervention to eliminate urogenital schistosomiasis in Zanzibar.

    PubMed

    Celone, Mike; Person, Bobbie; Ali, Said M; Lyimo, Jameelat H; Mohammed, Ulfat A; Khamis, Alippo N; Mohammed, Yussra S; Mohammed, Khalfan A; Rollinson, David; Knopp, Stefanie

    2016-11-01

    In Zanzibar, United Republic of Tanzania, Madrassa schools are influential institutions, where children and adults can learn about the interpretation of the Koran. We aimed to explore the involvement of Madrassa teachers for behavior change interventions in a randomized operational research trial designed to investigate the impact of multiple approaches to eliminate urogenital schistosomiasis transmission from Zanzibar. Madrassa teachers performing in the 30 communities of the behavior change study arm were trained in new interactive and participatory teaching methods by the local behavioral team and provided with schistosomiasis-teaching tools for teaching about transmission and prevention in their Madrassa. In July 2014, in a qualitative research study, we conducted 25 semi-structured interviews with Madrassa teachers to find out how they perceived their involvement in interventions against schistosomiasis. In 2014, 5926 among the 8497 registered Madrassa students in 30 communities on Unguja and Pemba islands received health education and participated in interactive behavior change exercises about schistosomiasis. Madrassa teachers reported that they valued their inclusion in the study and the opportunity to educate their students about schistosomiasis transmission, prevention, and treatment. They also perceived personal and community benefits as a result of their training and strongly supported the inclusion of additional Madrassa teachers in future intervention activities. Madrassa teachers are influential in the Zanzibari society, and hence are important change agents within our community-level behavioral intervention. They might constitute an untapped resource that can help to expand and increase acceptance of and participation in schistosomiasis and other neglected tropical disease control activities in African Muslim communities.

  14. Eradication of schistosomiasis in Guangxi, China. Part 2: Political economy, management strategy and costs, 1953-92.

    PubMed

    Sleigh, A; Jackson, S; Li, X; Huang, K

    1998-01-01

    Reported are the results of a study of the political economy, management, and costs of the successful Guangxi schistosomiasis eradication programme, spanning 40 years from 1953 to 1992. For this purpose we analysed all government data and memoranda on the policy, management, technical support, finance, and the control strategy of the programme. We also interviewed many local staff involved in the programme over the 40-year period and obtained cost data from annual county-level records on seven major categories of variable costs. Schistosomiasis control in Guangxi began with one of the first examples of community participation and rapid assessment in public health history--the use of pre-franked envelopes to return disease questionnaires and suspect snails from rural areas. This approach quickly and accurately delineated the endemic area. This was Mao Zedong's "mass line", incorporating ideas and knowledge from peasants directly into services run for and by them, here the schistosomiasis control programme. Recognition by China's leaders that schistosomiasis was a great economic burden, steadfast prioritizing of the programme over 40 years, local innovative scientific study, agricultural and environmental focus on eradicating the snail hosts and boosting rural production, and mass community education and support were all key factors in the final success. Local leaders motivated programme staff and everyone involved knew the objectives. The programme was always multisectoral, with policy developed centrally, and strategy and collaboration encouraged and rewarded at the grass-roots. These features explain how a very poor autonomous region such as Guangxi finally eradicated schistosomiasis, spending less than US$ 0.50 per protected citizen per year; it is remarkable that the disease and snails were initially found across a large area of complex environments and modern drugs such as praziquantel were not available for most of the 40-year period. The lessons from Guangxi

  15. Eradication of schistosomiasis in Guangxi, China. Part 2: Political economy, management strategy and costs, 1953-92.

    PubMed Central

    Sleigh, A.; Jackson, S.; Li, X.; Huang, K.

    1998-01-01

    Reported are the results of a study of the political economy, management, and costs of the successful Guangxi schistosomiasis eradication programme, spanning 40 years from 1953 to 1992. For this purpose we analysed all government data and memoranda on the policy, management, technical support, finance, and the control strategy of the programme. We also interviewed many local staff involved in the programme over the 40-year period and obtained cost data from annual county-level records on seven major categories of variable costs. Schistosomiasis control in Guangxi began with one of the first examples of community participation and rapid assessment in public health history--the use of pre-franked envelopes to return disease questionnaires and suspect snails from rural areas. This approach quickly and accurately delineated the endemic area. This was Mao Zedong's "mass line", incorporating ideas and knowledge from peasants directly into services run for and by them, here the schistosomiasis control programme. Recognition by China's leaders that schistosomiasis was a great economic burden, steadfast prioritizing of the programme over 40 years, local innovative scientific study, agricultural and environmental focus on eradicating the snail hosts and boosting rural production, and mass community education and support were all key factors in the final success. Local leaders motivated programme staff and everyone involved knew the objectives. The programme was always multisectoral, with policy developed centrally, and strategy and collaboration encouraged and rewarded at the grass-roots. These features explain how a very poor autonomous region such as Guangxi finally eradicated schistosomiasis, spending less than US$ 0.50 per protected citizen per year; it is remarkable that the disease and snails were initially found across a large area of complex environments and modern drugs such as praziquantel were not available for most of the 40-year period. The lessons from Guangxi

  16. [Human activities, hydro-agricultural management and urinary schistosomiasis. Methodological approach and results (a preliminary study in Upper-Volta)].

    PubMed

    Le Bras, M; Faucher, P; Giap, G; Meric, D; Commenges, D; Villenave, D; Camara, S; Gatheron, C; Appriou, M

    1982-01-01

    In the schistosomiasis endemic sub-sahelian region, a study of the prevalence of the disease was carried out on three different areas: the highest was around a small river, the lowest in the hydro-agricultural management region, mean prevalence was noted around a natural lake. Human activities have been classified with regards to the areas of transmission. Activity is closely linked to prevalence. For the populations, symptoms of urinary schistosomiasis (Rudzenga) constitute a real disease, traditional healers are the masters of earth (Tengsoba), water has hardly any importance in transmission.

  17. TROPISTIC BEHAVIOR IN SCHISTOSOMIASIS: MIRACIDIA AND CERCARIAE PREDATORS.

    DTIC Science & Technology

    Biomphalaria glabrata and cercariae of Schistosoma mansoni were tagged by exposing infected snails to H275SeO3 or 75Se-methionine. Labeled cercariae... mansoni cercariae occur after exposure to emulsions of epoxygeranylgeraniol at concentrations as low as 1 ppm. Cercariae exposed to 4 ppm

  18. Naturally Occurring Radioactive Materials (NORM)

    SciTech Connect

    Gray, P.

    1997-02-01

    This paper discusses the broad problems presented by Naturally Occuring Radioactive Materials (NORM). Technologically Enhanced naturally occuring radioactive material includes any radionuclides whose physical, chemical, radiological properties or radionuclide concentration have been altered from their natural state. With regard to NORM in particular, radioactive contamination is radioactive material in an undesired location. This is a concern in a range of industries: petroleum; uranium mining; phosphorus and phosphates; fertilizers; fossil fuels; forestry products; water treatment; metal mining and processing; geothermal energy. The author discusses in more detail the problem in the petroleum industry, including the isotopes of concern, the hazards they present, the contamination which they cause, ways to dispose of contaminated materials, and regulatory issues. He points out there are three key programs to reduce legal exposure and problems due to these contaminants: waste minimization; NORM assesment (surveys); NORM compliance (training).

  19. Schistosomiasis and soil-transmitted helminthiasis in Rwanda: an update on their epidemiology and control.

    PubMed

    Rujeni, Nadine; Morona, Domenica; Ruberanziza, Eugene; Mazigo, Humphrey D

    2017-03-01

    Even though Rwanda lies within a region that has a high prevalence of schistosomiasis and soil-transmitted helminth (STH) infections, epidemiological information regarding these infections in the country remains scarce. The present review attempts to compile the available data on schistosomiasis and STHs, from 1940 to 2014, to provide an insight on the epidemiological profile of these infections. This information will, in turn, support the design and implementation of sustainable control measures. The available records indicate that only Schistosoma mansoni and all the major species of STHs are endemic in Rwanda. In 2008, the national prevalence of S. mansoni was reported to be 2.7%, ranging from 0 to 69.5%, and that of STH infections was 65.8% (diagnosed using the Kato-Katz technique). The prevalence of these infections varies from one district to another, with schoolchildren remaining a highly affected group. The main control approach is mass drug administration using albendazole and praziquantel, mostly targeting school-aged children in school environments. In 2008, adult individuals living in areas with a prevalence of S. mansoni ≥30% were also included in the mass drug administration programme. However, despite Rwanda achieving an almost 100% coverage of this programme in 2008-2010, the transmission of S. mansoni and STHs continues to take place, as illustrated by the most recent surveys. If Rwanda is to achieve sustainable control and elimination of schistosomiasis and STHs, there is a need to revise the country's control strategy and adopt an integrated control approach that involves a combination of measures.

  20. Application of Radar Altimetry Methods to Monitoring of Parasitic Disease Transmission: Schistosomiasis in Poyang Lake, China

    NASA Astrophysics Data System (ADS)

    McCandless, M.; Ibaraki, M.; Shum, C.; Lee, H.; Liang, S.

    2008-12-01

    Schistosomiasis is the second-most prevalent tropical disease after malaria affecting two-hundred million people annually world-wide; it shortens lifespan on average by ten years in endemic areas and no vaccine exists. The current control methods of human host chemotherapy and application of molluscicides to the environment do not break the disease transmission cycle. Schistosomiasis transmission in southern China involves an amphibious intermediate host snail for which hydrology is a key factor because the adults need moist vegetation while the juveniles are fully aquatic. Thus, hydrology is a key factor in schistosomiasis transmission and understanding its role can inform control measures. Our objective is to integrate hydrologic, ecologic, and other environmental factors to determine the changes in available snail habitat through space and time. We use radar altimetry measurements to determine water level every 35 days when the Envisat (Environmental Satellite) passes over the lake. The radar altimetry readings have been calibrated to levels from in-situ gauging stations and will support remote analysis of disease transmission potential without the need for gauging station data. A geographic information system was used to combine key factors including water level, topography, and air temperature data to identify areas of available snail habitat. In order to accomplish this, we conducted three steps including: delineating the watershed, specifying potential snail habitat areas through topography and air temperature classification, and calculating the intersection between potential snail habitat and non-flooded areas in the watershed. Statistical analyses of total available habitat area are also conducted. These maps and statistics analyses can be used by public health agencies to monitor snail habitat trends over time. Coupling remote sensing of water levels with a geographic information system model will continue to be important as the hydrology of the lake

  1. The role of climate on prevalence or eradication of vesical schistosomiasis in Khuzestan Province of Iran.

    PubMed

    Hamidinia, Dariush; Maraghi, Sharif; Azimi, Farideh; Ai, Armin; Shirian, Sadegh

    2016-06-01

    Climate is defined as the combination of climate and air elements of a given region which is usually measured for a period of decades. De-marton climate classification has been established based on many factors, including elements such as temperature and rainfall. Vesicle schistosomiasis is a parasitic disease caused by Schistosoma haematobium. This parasite lives in the blood vessels of the bladder. The parasite can cause hematuria in human and if not treated properly can lead to vesicale carcinoma. The parasite is distributed only in certain parts of the province and it is highly dispersed along the rivers of Dez, Karkheh and Karun with high emissions. In 1970, the prevalence of infection in infected foci was 23.8 %. Campaign against the parasite began in 1958 but it did not encompass all centers of infection. Preventive measures include diagnosis and treatment of patients, public health promotion, health education, drying swamps and ponds, improving the environment, cementing the irrigation canals, and the use of moluscocide eventually leads to changing the ecological and conditions of parasite and snail inhabits. Application of preventive measures resulted in the reduction of infection level to 0.7 % in 1979. By continuing struggle and intensifying preventive measures and changing ecological and climatic environment, in 2008, the examination of 3400 urine samples of students in Andimeshk district revealed no cases of the vesical schistosomiasis. It is concluded that S. haematobium and vesical schistosomiasis is eliminated from Khuzestan province southwest Iran, but the disease is still prevalent in neighboring Iran's western border country (Iraq) and due to the special conditions of its facilities and the traffic between the two countries, it is necessary to control and eradicate the disease in Iraq by using the experiences of Iran in eliminating the disease.

  2. Galectin-3, histone deacetylases, and Hedgehog signaling: Possible convergent targets in schistosomiasis-induced liver fibrosis.

    PubMed

    de Oliveira, Felipe Leite; Carneiro, Katia; Brito, José Marques; Cabanel, Mariana; Pereira, Jonathas Xavier; Paiva, Ligia de Almeida; Syn, Wingkin; Henderson, Neil C; El-Cheikh, Marcia Cury

    2017-02-01

    Schistosomiasis affects approximately 240 million people in the world. Schistosoma mansoni eggs in the liver induce periportal fibrosis and hepatic failure driven by monocyte recruitment and macrophage activation, resulting in robust Th2 response. Here, we suggested a possible involvement of Galectin-3 (Gal-3), histone deacetylases (HDACs), and Hedgehog (Hh) signaling with macrophage activation during Th1/Th2 immune responses, fibrogranuloma reaction, and tissue repair during schistosomiasis. Gal-3 is highly expressed by liver macrophages (Kupffer cells) around Schistosoma eggs. HDACs and Hh regulate macrophage polarization and hepatic stellate cell activation during schistosomiasis-associated fibrogenesis. Previously, we demonstrated an abnormal extracellular matrix distribution in the liver that correlated with atypical monocyte-macrophage differentiation in S. mansoni-infected, Gal-3-deficient (Lgals3-/-) mice. New findings explored in this review focus on the chronic phase, when wild-type (Lgals3+/+) and Lgals3-/- mice were analyzed 90 days after cercariae infection. In Lgals3-/- infected mice, there was significant inflammatory infiltration with myeloid cells associated with egg destruction (hematoxylin and eosin staining), phagocytes (specifically Kupffer cells), numerically reduced and diffuse matrix extracellular deposition in fibrotic areas (Gomori trichrome staining), and severe disorganization of collagen fibers surrounding the S. mansoni eggs (reticulin staining). Granuloma-derived stromal cells (GR cells) of Lgals3-/- infected mice expressed lower levels of alpha smooth muscle actin (α-SMA) and eotaxin and higher levels of IL-4 than Lgals3+/+ mice (real-time PCR). The relevant participation of macrophages in these events led us to suggest distinct mechanisms of activation that culminate in defective fibrosis in the liver of Lgals3-/- infected mice. These aspects were discussed in this review, as well as the possible interference between Gal-3, HDACs

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

    PubMed Central

    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

  4. Galectin-3, histone deacetylases, and Hedgehog signaling: Possible convergent targets in schistosomiasis-induced liver fibrosis

    PubMed Central

    de Oliveira, Felipe Leite; Carneiro, Katia; Brito, José Marques; Cabanel, Mariana; Pereira, Jonathas Xavier; Paiva, Ligia de Almeida; Syn, Wingkin; Henderson, Neil C.; El-Cheikh, Marcia Cury

    2017-01-01

    Schistosomiasis affects approximately 240 million people in the world. Schistosoma mansoni eggs in the liver induce periportal fibrosis and hepatic failure driven by monocyte recruitment and macrophage activation, resulting in robust Th2 response. Here, we suggested a possible involvement of Galectin-3 (Gal-3), histone deacetylases (HDACs), and Hedgehog (Hh) signaling with macrophage activation during Th1/Th2 immune responses, fibrogranuloma reaction, and tissue repair during schistosomiasis. Gal-3 is highly expressed by liver macrophages (Kupffer cells) around Schistosoma eggs. HDACs and Hh regulate macrophage polarization and hepatic stellate cell activation during schistosomiasis-associated fibrogenesis. Previously, we demonstrated an abnormal extracellular matrix distribution in the liver that correlated with atypical monocyte–macrophage differentiation in S. mansoni-infected, Gal-3-deficient (Lgals3-/-) mice. New findings explored in this review focus on the chronic phase, when wild-type (Lgals3+/+) and Lgals3-/- mice were analyzed 90 days after cercariae infection. In Lgals3-/- infected mice, there was significant inflammatory infiltration with myeloid cells associated with egg destruction (hematoxylin and eosin staining), phagocytes (specifically Kupffer cells), numerically reduced and diffuse matrix extracellular deposition in fibrotic areas (Gomori trichrome staining), and severe disorganization of collagen fibers surrounding the S. mansoni eggs (reticulin staining). Granuloma-derived stromal cells (GR cells) of Lgals3-/- infected mice expressed lower levels of alpha smooth muscle actin (α-SMA) and eotaxin and higher levels of IL-4 than Lgals3+/+ mice (real-time PCR). The relevant participation of macrophages in these events led us to suggest distinct mechanisms of activation that culminate in defective fibrosis in the liver of Lgals3-/- infected mice. These aspects were discussed in this review, as well as the possible interference between Gal-3, HDACs

  5. Spatial patterns of schistosomiasis in Burkina Faso: relevance of human mobility and water resources development

    NASA Astrophysics Data System (ADS)

    Perez-Saez, Javier; Bertuzzo, Enrico; Frohelich, Jean-Marc; Mande, Theophile; Ceperley, Natalie; Sou, Mariam; Yacouba, Hamma; Maiga, Hamadou; Sokolow, Susanne; De Leo, Giulio; Casagrandi, Renato; Gatto, Marino; Mari, Lorenzo; Rinaldo, Andrea

    2015-04-01

    We study the spatial geography of schistosomiasis in the african context of Burkina Faso by means of a spatially explicit model of disease dynamics and spread. The relevance of our work lies in its ability to describe quantitatively a geographic stratification of the disease burden capable of reproducing important spatial differences, and drivers/controls of disease spread. Among the latters, we consider specifically the development and management of water resources which have been singled out empirically as an important risk factor for schistosomiasis. The model includes remotely acquired and objectively manipulated information on the distributions of population, infrastructure, elevation and climatic drivers. It also includes a general description of human mobility and addresses a first-order characterization of the ecology of the intermediate host of the parasite causing the disease based on maximum entropy learning of relevant environmenal covariates. Spatial patterns of the disease were analyzed about their disease-free equilibrium by proper extraction and mapping of suitable eigenvectors of the Jacobian matrix subsuming all stability properties of the system. Human mobility was found to be a primary control of both pathogen invasion success and of the overall distribution of disease burden. The effects of water resources development were studied by accounting for the (prior and posterior) average distances of human settlements from water bodies that may serve as suitable habitats to the intermediate host of the parasite. Water developments, in combination with human mobility, were quantitatively related to disease spread into regions previously nearly disease-free and to large-scale empirical incidence patterns. We concluded that while the model still needs refinements based on field and epidemiological evidence, the framework proposed provides a powerful tool for large-scale, long-term public health planning and management of schistosomiasis.

  6. Independent origins of loss-of-function mutations conferring oxamniquine resistance in a Brazilian schistosome population.

    PubMed

    Chevalier, Frédéric D; Le Clec'h, Winka; Eng, Nina; Rugel, Anastasia R; Assis, Rafael Ramiro de; Oliveira, Guilherme; Holloway, Stephen P; Cao, Xiaohang; Hart, P John; LoVerde, Philip T; Anderson, Timothy J C

    2016-06-01

    Molecular surveillance provides a powerful approach to monitoring the resistance status of parasite populations in the field and for understanding resistance evolution. Oxamniquine was used to treat Brazilian schistosomiasis patients (mid-1970s to mid-2000s) and several cases of parasite infections resistant to treatment were recorded. The gene underlying resistance (SmSULT-OR) encodes a sulfotransferase required for intracellular drug activation. Resistance has a recessive basis and occurs when both SmSULT-OR alleles encode for defective proteins. Here we examine SmSULT-OR sequence variation in a natural schistosome population in Brazil ∼40years after the first use of this drug. We sequenced SmSULT-OR from 189 individual miracidia (1-11 per patient) recovered from 49 patients, and tested proteins expressed from putative resistance alleles for their ability to activate oxamniquine. We found nine mutations (four non-synonymous single nucleotide polymorphisms, three non-coding single nucleotide polymorphisms and two indels). Both mutations (p.E142del and p.C35R) identified previously were recovered in this field population. We also found two additional mutations (a splice site variant and 1bp coding insertion) predicted to encode non-functional truncated proteins. Two additional substitutions (p.G206V, p.N215Y) tested had no impact on oxamniquine activation. Three results are of particular interest: (i) we recovered the p.E142del mutation from the field: this same deletion is responsible for resistance in an oxamniquine selected laboratory parasite population; (ii) frequencies of resistance alleles are extremely low (0.27-0.8%), perhaps due to fitness costs associated with carriage of these alleles; (iii) that four independent resistant alleles were found is consistent with the idea that multiple mutations can generate loss-of-function alleles.

  7. Health education, public information, and communication in schistosomiasis control in Brazil: a brief retrospective and perspectives.

    PubMed

    Schall, V T

    1995-01-01

    In recent years, the strategy for the control of schistosomiasis has placed increased emphasis on the role of health education, public information, and communication. This should, not only bring about specific changes in behavior aiming at disease prevention, but also stimulate participation of the community in health programs. Beyond this, it is desirable that both community members and researchers should seek better life conditions through a transformative social action. The present paper addresses these concerns; first, by critically reviewing some health education programs that were developed in Brazil, and, secondly, by analyzing and suggesting ways to improve this area.

  8. [Chemoprophylactic activity of soaps containing essential oil from the fruit of Pterodon pubescens in schistosomiasis mansoni].

    PubMed

    Santos Filho, D; Sarti, S J; Katz, N; Araújo, N; Rocha Filho, P A; Abreu, J E; Bortolin, M E

    1987-01-01

    It has been studied the chemoprophylactic action on experimental schistosomiasis of the essential oil from Pterodon pubescens "sucupira branca" as an additive through different formulations, in toilet soap. Immediately or 24 hours later, groups of mice were exposed by tail method to Schistosoma mansoni cercariae. After 45 days of the exposition, the protective action of these soaps were evaluated. The results showed different levels of protection, ranging from 29.0 to 100.0%. Further studies are on going with the most promising formulations.

  9. Low genetic diversity in a snail intermediate host (Biomphalaria pfeifferi Krass, 1848) and schistosomiasis transmission in the Senegal River Basin.

    PubMed

    Campbell, G; Noble, L R; Rollinson, D; Southgate, V R; Webster, J P; Jones, C S

    2010-01-01

    Population genetic perturbations of intermediate hosts, often a consequence of human pressure on environmental resources, can precipitate unexpectedly severe disease outbreaks. Such disturbances are set to become increasingly common following range changes concomitant with climate shifts, dwindling natural resources and major infrastructure changes such as hydroprojects. Construction of the Diama dam in the Senegal River Basin (SRB) reduced river salinity, enabling the freshwater snail intermediate host Biomphalaria pfeifferi to rapidly expand its distribution. A serious public health problem ensued, with an epidemic of intestinal schistosomiasis occurring in the previously schistosome-free Richard-Toll region within 2 years. The current study aimed to assess the population variability of B. pfeifferi in the SRB, and speculate upon its subsequent impact on host-parasite interactions following such engineered ecological change. Genetic variation at nine polymorphic microsatellite loci revealed little population differentiation in SRB snails compared with those from natural habitats in Zimbabwe, where Schistosoma mansoni transmission is much lower. 'Open' SRB habitats are associated with greater water contact, smaller population sizes and less genetic diversity, with sites downstream of Richard-Toll showing greater inter- and intrapopulation variation, concomitant with less frequent human contact. These observations may be explained by rapid expansion into pristine habitat selecting for high fecundity genotypes at the expense of schistosome resistance, presenting S. mansoni with genetically homogenous highly fecund susceptible populations around the focal point, promoting development of a highly compatible host-parasite relationship. Longitudinal study of such systems may prove important in predicting public health risks engendered by future environmental engineering projects.

  10. Improved Perceptions and Practices Related to Schistosomiasis and Intestinal Worm Infections Following PHAST Intervention on Kome Island, North-Western Tanzania

    PubMed Central

    Mwanga, Joseph R.; Kaatano, Godfrey M.; Siza, Julius E.; Chang, Su Young; Ko, Yunsuk; Kullaya, Cyril M.; Nsabo, Jackson; Eom, Keeseon S.; Yong, Tai-Soon; Chai, Jong-Yil; Min, Duk-Young; Rim, Han-Jong; Changalucha, John M.

    2015-01-01

    Schistosomiasis and intestinal worm infections are widespread diseases of public health importance in Tanzania. A study on perceptions and practices related to schistosomiasis and intestinal worm infections was undertaken among a community population of Kome Island in Sengerema District, north-western Tanzania, where intestinal schistosomiasis and intestinal worm infections are endemic. Schistosomiasis and intestinal worm-related perceptions and practices were assessed before and 3 years after implementation of a participatory hygiene and sanitation transformation (PHAST) intervention as a control measure. Data were obtained from baseline and post-intervention knowledge, attitudes, and practices (KAP) questionnaire surveys conducted twice in 2009 and 2012 among 82 individuals aged ≥15 years. We found significant increases in respondents’ knowledge of the cause, transmission, symptoms, health consequences, and prevention of schistosomiasis and intestinal worm infections after PHAST intervention. The increase in respondents’ knowledge on almost all aspects of the said infections was translated into actions to control schistosomiasis and intestinal worm infections. This has not been achieved by chance, but due to well-designed and locally-adapted PHAST intervention. We conclude that despite criticisms, PHAST approach is still useful in empowering communities to control water, sanitation, and hygiene related infectious diseases such as schistosomiasis and intestinal worm infections. PMID:26537035

  11. Systematic review of pentachlorophenol occurrence in the environment and in humans in China: not a negligible health risk due to the re-emergence of schistosomiasis.

    PubMed

    Zheng, Weiwei; Yu, Huan; Wang, Xia; Qu, Weidong

    2012-07-01

    Pentachlorophenol (PCP) has been widely used for killing snails in areas of China where schistosomiasis is epidemic. With the re-emergence of schistosomiasis, the warranted production and consumption of PCP has inevitably resulted in persistent environmental contamination by it and its impurities, polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). This study aimed to evaluate the contamination status and human burden of PCP and its impurities (PCDD/Fs) in China, considering the previous epidemic and re-emergence of schistosomiasis. We searched studies relevant to PCP occurrence in the environment and in humans in China. Data on snail elimination areas were included to estimate PCP consumption. Relevant publications were analyzed to distinguish PCDD/Fs contamination from PCP usage. PCP contamination was detected ubiquitously in various environmental media and in human samples; environmental levels were generally low, with the exception of some hot spots. In schistosomiasis-epidemic areas, there were significantly higher PCP levels in the environment and in humans than in control areas. Spatial disparities indicated the consistency between serious schistosomiasis epidemic areas and hot spots of PCP contamination. The data suggest an increased trend in PCP contamination of the environment. Specific PCDD/Fs contamination from PCP usage existed even at low environmental levels. The occurrence of PCP in the environment and in humans positively correlated with the epidemic of schistosomiasis. Thyroid-disrupting effects and cancer risk caused by PCP and PCDD/Fs even at low environmental levels in China's schistosomiasis-epidemic areas are of concern.

  12. Improved Perceptions and Practices Related to Schistosomiasis and Intestinal Worm Infections Following PHAST Intervention on Kome Island, North-Western Tanzania.

    PubMed

    Mwanga, Joseph R; Kaatano, Godfrey M; Siza, Julius E; Chang, Su Young; Ko, Yunsuk; Kullaya, Cyril M; Nsabo, Jackson; Eom, Keeseon S; Yong, Tai-Soon; Chai, Jong-Yil; Min, Duk-Young; Rim, Han-Jong; Changalucha, John M

    2015-10-01

    Schistosomiasis and intestinal worm infections are widespread diseases of public health importance in Tanzania. A study on perceptions and practices related to schistosomiasis and intestinal worm infections was undertaken among a community population of Kome Island in Sengerema District, north-western Tanzania, where intestinal schistosomiasis and intestinal worm infections are endemic. Schistosomiasis and intestinal worm-related perceptions and practices were assessed before and 3 years after implementation of a participatory hygiene and sanitation transformation (PHAST) intervention as a control measure. Data were obtained from baseline and post-intervention knowledge, attitudes, and practices (KAP) questionnaire surveys conducted twice in 2009 and 2012 among 82 individuals aged ≥15 years. We found significant increases in respondents' knowledge of the cause, transmission, symptoms, health consequences, and prevention of schistosomiasis and intestinal worm infections after PHAST intervention. The increase in respondents' knowledge on almost all aspects of the said infections was translated into actions to control schistosomiasis and intestinal worm infections. This has not been achieved by chance, but due to well-designed and locally-adapted PHAST intervention. We conclude that despite criticisms, PHAST approach is still useful in empowering communities to control water, sanitation, and hygiene related infectious diseases such as schistosomiasis and intestinal worm infections.

  13. The prevalence of schistosomiasis in school-aged children as an appropriate indicator of its prevalence in the community.

    PubMed

    Pereira, Ana Paula Braz; Favre, Tereza Cristina; Galvão, Aline Favre; Beck, Lilian; Barbosa, Constança Simões; Pieri, Otávio Sarmento

    2010-07-01

    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.

  14. Impact of Climate Variability on Prevalence of Urinary Schistosomiasis over Sunyani in the Transition Belt of Ghana

    NASA Astrophysics Data System (ADS)

    Tay, S. K.; Amekudzi, L. K.; Tagoe, G.

    2012-04-01

    A study has been conducted to determine the impact of climate variability on Schistosoma haematobium infection among patients and school children in Sunyani between 2006 and 2009. Urine samples from the subjects were collected and examined in the laboratory using the filtration technique for the detection and quantification of Schistosomiasis haematobium eggs. The prevalence rate of urinary schistosomiasis at the Sunyani Regional Hospital for 2006, 2007, 2008 and 2009 were found to be 0.24%, 0.55%, 0.55% and 0.75% respectively while that for Methodist Junior High School in 2008 and 2009 were 60.1% and 60.3% respectively. A decrease in the relative humidity and average annual rainfall were identified as factors contributory to the increase in urinary Schistosomiasis prevalence rate. The temperature values obtained throughout the study period did not have any significant effect on the prevalence rate. The temperature values, however, were those that enhanced cercarial incubation (15-35˚C) with a resultant increase in shedding of cercariae leading to more infections among water contacts. The infection rate due to stream Amama was 20.1%, while that due to river Tano was 36.6%. The highest risk group was children aged 15-19 years. Praziquantel was administered to treat the infection, producing a cure rate of 93%. Recognition of urinary Schistosomiasis as a public health problem in Ghana is the main challenge to prevention and control of the disease.

  15. Schistosomiasis control in China: the impact of a 10-year World Bank Loan Project (1992-2001).

    PubMed Central

    Xianyi, Chen; Liying, Wang; Jiming, Cai; Xiaonong, Zhou; Jiang, Zheng; Jiagang, Guo; Xiaohua, Wu; Engels, D.; Minggang, Chen

    2005-01-01

    China has been carrying out large-scale schistosomiasis control since the mid-1950s, but in the early 1990s, schistosomiasis was still endemic in eight provinces. A World Bank Loan Project enabled further significant progress to be made during the period 1992-2001. The control strategy was focused on the large-scale use of chemotherapy -- primarily to reinforce morbidity control -- while at the same time acting on transmission with the ultimate goal of interrupting it. Chemotherapy was complemented by health education, chemical control of snails and environmental modification where appropriate. A final evaluation in 2002 showed that infection rates in humans and livestock had decreased by 55% and 50%, respectively. The number of acute infections and of individuals with advanced disease had also significantly decreased. Although snail infection rates continued to fluctuate at a low level, the densities of infected snails had decreased by more than 75% in all endemic areas. The original objectives of the China World Bank Loan Project for schistosomiasis control had all been met. One province, Zhejiang, had already fulfilled the criteria for elimination of schistosomiasis by 1995. The project was therefore a success and has provided China with a sound basis for further control. PMID:15682248

  16. Development of “-omics” research in Schistosoma spp. and -omics-based new diagnostic tools for schistosomiasis

    PubMed Central

    Wang, Shuqi; Hu, Wei

    2014-01-01

    Schistosomiasis, caused by dioecious flatworms in the genus Schistosoma, is torturing people from many developing countries nowadays and frequently leads to severe morbidity and mortality of the patients. Praziquantel based chemotherapy and morbidity control for this disease adopted currently necessitate viable and efficient diagnostic technologies. Fortunately, those “-omics” researches, which rely on high-throughput experimental technologies to produce massive amounts of informative data, have substantially contributed to the exploitation and innovation of diagnostic tools of schistosomiasis. In its first section, this review provides a concise conclusion on the progresses pertaining to schistosomal “-omics” researches to date, followed by a comprehensive section on the diagnostic methods of schistosomiasis, especially those innovative ones based on the detection of antibodies, antigens, nucleic acids, and metabolites with a focus on those achievements inspired by “-omics” researches. Finally, suggestions about the design of future diagnostic tools of schistosomiasis are proposed, in order to better harness those data produced by “-omics” studies. PMID:25018752

  17. Rapid mapping of schistosomiasis and other neglected tropical diseases in the context of integrated control programmes in Africa.

    PubMed

    Brooker, S; Kabatereine, N B; Gyapong, J O; Stothard, J R; Utzinger, J

    2009-11-01

    There is growing interest and commitment to the control of schistosomiasis and other so-called neglected tropical diseases (NTDs). Resources for control are inevitably limited, necessitating assessment methods that can rapidly and accurately identify and map high-risk communities so that interventions can be targeted in a spatially-explicit and cost-effective manner. Here, we review progress made with (1) mapping schistosomiasis across Africa using available epidemiological data and, more recently, climate-based risk prediction; (2) the development and use of morbidity questionnaires for rapid identification of high-risk communities of urinary schistosomiasis; and (3) innovative sampling-based approaches for intestinal schistosomiasis, using the lot quality assurance sampling technique. Experiences are also presented for the rapid mapping of other NTDs, including onchocerciasis, loiasis and lymphatic filariasis. Future directions for an integrated rapid mapping approach targeting multiple NTDs simultaneously are outlined, including potential challenges in developing an integrated survey tool. The lessons from the mapping of human helminth infections may also be relevant for the rapid mapping of malaria as its control efforts are intensified.

  18. The first step toward diagnosing female genital schistosomiasis by computer image analysis.

    PubMed

    Holmen, Sigve Dhondup; Kleppa, Elisabeth; Lillebø, Kristine; Pillay, Pavitra; van Lieshout, Lisette; Taylor, Myra; Albregtsen, Fritz; Vennervald, Birgitte Jyding; Onsrud, Mathias; Kjetland, Eyrun Floerecke

    2015-07-01

    Schistosoma haematobium causes female genital schistosomiasis (FGS), which is a poverty-related disease in sub-Saharan Africa. Furthermore, it is co-endemic with human immunodeficiency virus (HIV), and biopsies from genital lesions may expose the individual to increased risk of HIV infection. However, microscopy of urine and hematuria are nonspecific and insensitive predictors of FGS and gynecological investigation requires extensive training. Safe and affordable diagnostic methods are needed. We explore a novel method of diagnosing FGS using computer color analysis of colposcopic images. In a cross-sectional study on young women in an endemic area, we found strong associations between the output from the computer color analysis and both clinical diagnosis (odds ratio [OR] = 5.97, P < 0.001) and urine microscopy for schistosomiasis (OR = 3.52, P = 0.004). Finally, using latent class statistics, we estimate that the computer color analysis yields a sensitivity of 80.5% and a specificity of 66.2% for the diagnosis of FGS.

  19. [Chemoprophylactic activity on Schistosomiasis mansoni of soaps containing essential oil from the fruits of Pterodon pubescens].

    PubMed

    Katz, N; dos Santos Filho, D; Sarti, S J; Mendes, N M; Rocha Filho, P A; Araujo, N

    1993-01-01

    The chemoprophylactic action of the essential oil of the fruit of Pterodon pubescens Benth (Leguminosae), incorporated in different soap formulations, was studied in experimental schistosomiasis. The formulations were used locally on the tails of mice which were exposed to Schistosoma mansoni cercariae immediately, 24, 72 or 168 hours later by the method of tail immersion. Protection was evaluated 45 days after exposure when the mice were sacrificed and the worms collected by perfusion. The results showed levels of protection varying from 0.0 to 100% depending on the formulation used. A methodology that allowed the evaluation of soap protection of mice exposed to natural infection in snail infested streams on the outskirts of Belo Horizonte, MG, was also developed. Promising results were obtained in that protection of between 57.5 and 31.1% was observed in field trials when soap was applied to the animals 24 and 48 hours earlier. Preliminary studies evaluating irritation and toxicity were favorable and showed that this new prophylactic weapon could contribute to the control of schistosomiasis.

  20. Spatial modeling of the schistosomiasis mansoni in Minas Gerais State, Brazil using spatial regression.

    PubMed

    Fonseca, F; Freitas, C; Dutra, L; Guimarães, R; Carvalho, O

    2014-05-01

    Schistosomiasis is a transmissible parasitic disease caused by the etiologic agent Schistosoma mansoni, whose intermediate hosts are snails of the genus Biomphalaria. The main goal of this paper is to estimate the prevalence of schistosomiasis in Minas Gerais State in Brazil using spatial disease information derived from the state transportation network of roads and rivers. The spatial information was incorporated in two ways: by introducing new variables that carry spatial neighborhood information and by using spatial regression models. Climate, socioeconomic and environmental variables were also used as co-variables to build models and use them to estimate a risk map for the whole state of Minas Gerais. The results show that the models constructed from the spatial regression produced a better fit, providing smaller root mean square error (RMSE) values. When no spatial information was used, the RMSE for the whole state of Minas Gerais reached 9.5%; with spatial regression, the RMSE reaches 8.8% (when the new variables are added to the model) and 8.5% (with the use of spatial regression). Variables representing vegetation, temperature, precipitation, topography, sanitation and human development indexes were important in explaining the spread of disease and identified certain conditions that are favorable for disease development. The use of spatial regression for the network of roads and rivers produced meaningful results for health management procedures and directing activities, enabling better detection of disease risk areas.

  1. The First Step Toward Diagnosing Female Genital Schistosomiasis by Computer Image Analysis

    PubMed Central

    Holmen, Sigve Dhondup; Kleppa, Elisabeth; Lillebø, Kristine; Pillay, Pavitra; van Lieshout, Lisette; Taylor, Myra; Albregtsen, Fritz; Vennervald, Birgitte Jyding; Onsrud, Mathias; Kjetland, Eyrun Floerecke

    2015-01-01

    Schistosoma haematobium causes female genital schistosomiasis (FGS), which is a poverty-related disease in sub-Saharan Africa. Furthermore, it is co-endemic with human immunodeficiency virus (HIV), and biopsies from genital lesions may expose the individual to increased risk of HIV infection. However, microscopy of urine and hematuria are nonspecific and insensitive predictors of FGS and gynecological investigation requires extensive training. Safe and affordable diagnostic methods are needed. We explore a novel method of diagnosing FGS using computer color analysis of colposcopic images. In a cross-sectional study on young women in an endemic area, we found strong associations between the output from the computer color analysis and both clinical diagnosis (odds ratio [OR] = 5.97, P < 0.001) and urine microscopy for schistosomiasis (OR = 3.52, P = 0.004). Finally, using latent class statistics, we estimate that the computer color analysis yields a sensitivity of 80.5% and a specificity of 66.2% for the diagnosis of FGS. PMID:25918212

  2. Universal Stress Proteins as New Targets for Environmental and Therapeutic Interventions of Schistosomiasis

    PubMed Central

    Masamba, Priscilla; Adenowo, Abiola Fatimah; Oyinloye, Babatunji Emmanuel; Kappo, Abidemi Paul

    2016-01-01

    In spite of various control measures and eradication methods that have been in progress, schistosomiasis still prevails as one of the most prevalent debilitating parasitic diseases, typically affecting the poor and the underprivileged that are predominantly concentrated in sub-Saharan Africa. The parasitic schistosome blood fluke responsible for causing the disease completes its complex developmental cycle in two hosts: humans and freshwater snails, where they physically undergo gross modifications to endure the different conditions associated with each host. Just like any other organism, the worm possesses mechanisms that help them respond to environmental insults. It has been hypothesized that a special class of proteins known as Universal Stress Proteins (USPs) are up-regulated during sudden environmental changes, thus assisting the worm to tolerate the unfavourable conditions associated with its developmental cycle. The position of praziquantel as the drug of choice against all schistosome infections has been deemed vulnerable due to mounting concerns over drug pressure and so the need for alternative treatment is now a matter of urgency. Therefore, this review seeks to explore the associations and possible roles of USPs in schistosomiasis as well as the functioning of these proteins in the schistosomulae stage in order to develop new therapeutic interventions against this disease. PMID:27706050

  3. Temperature data from satellite imagery and the distribution of schistosomiasis in Egypt.

    PubMed

    Malone, J B; Huh, O K; Fehler, D P; Wilson, P A; Wilensky, D E; Holmes, R A; Elmagdoub, A I

    1994-06-01

    Polar orbiting environmental satellites operated by the National Oceanographic and Atmospheric Administration acquire daytime and nighttime thermal infrared measurements of the earth's surface around the world at a spatial resolution of 1.1 km. Day-night pairs of this imagery from the Advanced Very High Resolution Radiometer (AVHRR) were processed to produce temperature maximum, temperature minimum, and diurnal temperature difference (dT) maps of the lower Nile River valley. Nile delta subsets of the dT maps for August 16, 1990 and February 14, 1991 were analyzed in detail. Values of dT at specific locations were derived using the median of 5 x 5 pixels centered on the latitude and longitude of 41 survey sites listed in 1935, 1983, and 1990 schistosomiasis surveys of the Nile Delta. A Spearman correlation coefficient matrix revealed an inverse relationship between site dT values for August 16, 1990 and February 14, 1991 and prevalence of Schistosoma mansoni in the 1935 and 1983 surveys. For S. haematobium, a positive association of site dT values and prevalence was seen for 1935 only. A significant association was observed between 1935 S. mansoni prevalence and that observed in 1983 and 1990; S. haematobium prevalence in 1935 was not correlated with the later surveys. The results suggest that AVHRR thermal difference maps reflect regional hydrologic conditions that can be used as a predictor of environmental risk of schistosomiasis for control program management.

  4. Circulating cathodic antigen cassette test versus haematuria strip test in diagnosis of urinary schistosomiasis.

    PubMed

    El-Ghareeb, Azza S; Abd El Motaleb, Ghada S; Waked, Nevien Maher; Osman Hany Kamel, Nancy; Aly, Nagwa Shaban

    2016-12-01

    Urinary schistosomiasis caused by Schistosoma haematobium constitutes a major public health problem in many tropical and sub-tropical countries. This study was conducted to evaluate circulating cathodic antigen cassette test and haematuria strip test for detection of S. haematobium in urine samples and to evaluate their screening performance among the study population. Microscopy was used as a gold standard. A total of 600 urine samples were examined by microscopy for detection of S. haematobium eggs, screened for microhaematuria using Self-Stik reagent strips and screened for circulating cathodic antigen (CCA) using the urine-CCA cassette test. The specificity of CCA, microhaematuria and macrohaematuria was 96.4, 40.6 and 31.2 % respectively while the sensitivity was 88.2, 99.3 and 100 % respectively which was statistically significant (P < 0.001). These findings suggest that using of urine-CCA cassette test in diagnosis of urinary schistosomiasis is highly specific (96.4 %) compared with the highly sensitive haematuria strip test (100 %). The degree of agreement between microscopic examination and CCA detection was 99.3 % with highly statistically significant difference (P < 0.001). The combination of two techniques could potentially use for screening and mapping of S. haematobium infection.

  5. When Yawning Occurs in Elephants

    PubMed Central

    Rossman, Zoë T.; Hart, Benjamin L.; Greco, Brian J.; Young, Debbie; Padfield, Clare; Weidner, Lisa; Gates, Jennifer; Hart, Lynette A.

    2017-01-01

    Yawning is a widely recognized behavior in mammalian species. One would expect that elephants yawn, although to our knowledge, no one has reported observations of yawning in any species of elephant. After confirming a behavioral pattern matching the criteria of yawning in two Asian elephants (Elephas maximus) in a zoological setting, this study was pursued with nine captive African elephants (Loxodonta africana) at a private reserve in the Western Cape, South Africa, the Knysna Elephant Park. Observations were made in June–September and in December. In the daytime, handlers managed seven of the elephants for guided interactions with visitors. At night, all elephants were maintained in a large enclosure with six having limited outdoor access. With infrared illumination, the elephants were continuously recorded by video cameras. During the nights, the elephants typically had 1–3 recumbent sleeping/resting bouts, each lasting 1–2 h. Yawning was a regular occurrence upon arousal from a recumbency, especially in the final recumbency of the night. Yawning was significantly more frequent in some elephants. Yawning was rare during the daytime and during periods of standing around in the enclosure at night. In six occurrences of likely contagious yawning, one elephant yawned upon seeing another elephant yawning upon arousal from a final recumbency; we recorded the sex and age category of the participants. The generality of yawning in both African and Asian elephants in other environments was documented in video recordings from 39 zoological facilities. In summary, the study provides evidence that yawning does occur in both African and Asian elephants, and in African elephants, yawning was particularly associated with arousal from nighttime recumbencies. PMID:28293560

  6. When Yawning Occurs in Elephants.

    PubMed

    Rossman, Zoë T; Hart, Benjamin L; Greco, Brian J; Young, Debbie; Padfield, Clare; Weidner, Lisa; Gates, Jennifer; Hart, Lynette A

    2017-01-01

    Yawning is a widely recognized behavior in mammalian species. One would expect that elephants yawn, although to our knowledge, no one has reported observations of yawning in any species of elephant. After confirming a behavioral pattern matching the criteria of yawning in two Asian elephants (Elephas maximus) in a zoological setting, this study was pursued with nine captive African elephants (Loxodonta africana) at a private reserve in the Western Cape, South Africa, the Knysna Elephant Park. Observations were made in June-September and in December. In the daytime, handlers managed seven of the elephants for guided interactions with visitors. At night, all elephants were maintained in a large enclosure with six having limited outdoor access. With infrared illumination, the elephants were continuously recorded by video cameras. During the nights, the elephants typically had 1-3 recumbent sleeping/resting bouts, each lasting 1-2 h. Yawning was a regular occurrence upon arousal from a recumbency, especially in the final recumbency of the night. Yawning was significantly more frequent in some elephants. Yawning was rare during the daytime and during periods of standing around in the enclosure at night. In six occurrences of likely contagious yawning, one elephant yawned upon seeing another elephant yawning upon arousal from a final recumbency; we recorded the sex and age category of the participants. The generality of yawning in both African and Asian elephants in other environments was documented in video recordings from 39 zoological facilities. In summary, the study provides evidence that yawning does occur in both African and Asian elephants, and in African elephants, yawning was particularly associated with arousal from nighttime recumbencies.

  7. Nipah virus entry can occur by macropinocytosis

    SciTech Connect

    Pernet, Olivier; Pohl, Christine; Ainouze, Michelle; Kweder, Hasan; Buckland, Robin

    2009-12-20

    Nipah virus (NiV) is a zoonotic biosafety level 4 paramyxovirus that emerged recently in Asia with high mortality in man. NiV is a member, with Hendra virus (HeV), of the Henipavirus genus in the Paramyxoviridae family. Although NiV entry, like that of other paramyxoviruses, is believed to occur via pH-independent fusion with the host cell's plasma membrane we present evidence that entry can occur by an endocytic pathway. The NiV receptor ephrinB2 has receptor kinase activity and we find that ephrinB2's cytoplasmic domain is required for entry but is dispensable for post-entry viral spread. The mutation of a single tyrosine residue (Y304F) in ephrinB2's cytoplasmic tail abrogates NiV entry. Moreover, our results show that NiV entry is inhibited by constructions and drugs specific for the endocytic pathway of macropinocytosis. Our findings could potentially permit the rapid development of novel low-cost antiviral treatments not only for NiV but also HeV.

  8. Long-term effectiveness of the integrated schistosomiasis control strategy with emphasis on infectious source control in China: a 10-year evaluation from 2005 to 2014.

    PubMed

    Wang, Xiaoli; Wang, Wei; Wang, Peng

    2017-02-01

    Schistosomiasis is a neglected tropical parasitic disease of great public health significance worldwide. Currently, mass drug administration with praziquantel remains the major strategy for global schistosomiasis control programs. Since 2005, an integrated strategy with emphasis on infectious source control was implemented for the control of schistosomiasis japonica, a major public health concern in China, and pilot studies have demonstrated that such a strategy is effective to reduce the prevalence of Schistosoma japonicum infection in both humans and bovines. However, there is little knowledge on the long-term effectiveness of this integrated strategy for controlling schistosomiasis japonica. The aim of this study was to evaluate the long-term effectiveness of the integrated strategy for schistosomiasis control following the 10-year implementation, based on the data from the national schistosomiasis control program released by the Ministry of Health, People's Republic of China. In 2014, there were 5 counties in which the transmission of schistosomiasis japonica had not been interrupted, which reduced by 95.2% as compared to that in 2005 (105 counties). The number of schistosomiasis patients and acute cases reduced by 85.5 and 99.7% in 2014 (115,614 cases and 2 cases) as compared to that in 2005 (798,762 cases and 564 cases), and the number of bovines and S. japonicum-infected bovines reduced by 47.9 and 98% in 2014 (919,579 bovines and 666 infected bovines) as compared to that in 2005 (1,764,472 bovines and 33,736 infected bovines), respectively. During the 10-year implementation of the integrated strategy, however, there was a minor fluctuation in the area of Oncomelania hupensis snail habitats, and there was only a 5.6% reduction in the area of snail habitats in 2014 relative to in 2005. The results of the current study demonstrate that the 10-year implementation of the integrated strategy with emphasis on infectious source has greatly reduced schistosomiasis

  9. HEALTH EDUCATION AND THE CONTROL OF UROGENITAL SCHISTOSOMIASIS: ASSESSING THE IMPACT OF THE JUMA NA KICHOCHO COMIC-STRIP MEDICAL BOOKLET IN ZANZIBAR.

    PubMed

    Stothard, J R; Khamis, A N; Khamis, I S; Neo, C H E; Wei, I; Rollinson, D

    2016-09-01

    Endeavours to control urogenital schistosomiasis on Unguja Island (Zanzibar) have focused on school-aged children. To assess the impact of an associated health education campaign, the supervised use of the comic-strip medical booklet Juma na Kichocho by Class V pupils attending eighteen primary schools was investigated. A validated knowledge and attitudes questionnaire was completed at baseline and repeated one year later following the regular use of the booklet during the calendar year. A scoring system (ranging from 0.0 to 5.0) measured children's understandings of schistosomiasis and malaria, with the latter being a neutral comparator against specific changes for schistosomiasis. In 2006, the average score from 751 children (328 boys and 423 girls) was 2.39 for schistosomiasis and 3.03 for malaria. One year later, the score was 2.43 for schistosomiasis and 2.70 for malaria from 779 children (351 boys and 428 girls). As might be expected, knowledge and attitudes scores for schistosomiasis increased (+0.05), but not as much as originally hoped, while the score for malaria decreased (-0.33). According to a Kolmogorov-Smirnov test, neither change was statistically significant. Analysis also revealed that 75% of school children misunderstood the importance of reinfection after treatment with praziquantel. These results are disappointing. They demonstrate that it is mistaken to assume that knowledge conveyed in child-friendly booklets will necessarily be interpreted, and acted upon, in the way intended. If long-term sustained behavioural change is to be achieved, health education materials need to engage more closely with local understandings and responses to urogenital schistosomiasis. This, in turn, needs to be part of the development of a more holistic, biosocial approach to the control of schistosomiasis.

  10. The Rapid-Heat LAMPellet Method: A Potential Diagnostic Method for Human Urogenital Schistosomiasis

    PubMed Central

    Carranza-Rodríguez, Cristina; Pérez-Arellano, José Luis; Vicente, Belén; López-Abán, Julio; Muro, Antonio

    2015-01-01

    Background Urogenital schistosomiasis due to Schistosoma haematobium is a serious underestimated public health problem affecting 112 million people - particularly in sub-Saharan Africa. Microscopic examination of urine samples to detect parasite eggs still remains as definitive diagnosis. This work was focussed on developing a novel loop-mediated isothermal amplification (LAMP) assay for detection of S. haematobium DNA in human urine samples as a high-throughput, simple, accurate and affordable diagnostic tool to use in diagnosis of urogenital schistosomiasis. Methodology/Principal Findings A LAMP assay targeting a species specific sequence of S. haematobium ribosomal intergenic spacer was designed. The effectiveness of our LAMP was assessed in a number of patients´ urine samples with microscopy confirmed S. haematobium infection. For potentially large-scale application in field conditions, different DNA extraction methods, including a commercial kit, a modified NaOH extraction method and a rapid heating method were tested using small volumes of urine fractions (whole urine, supernatants and pellets). The heating of pellets from clinical samples was the most efficient method to obtain good-quality DNA detectable by LAMP. The detection limit of our LAMP was 1 fg/µL of S. haematobium DNA in urine samples. When testing all patients´ urine samples included in our study, diagnostic parameters for sensitivity and specificity were calculated for LAMP assay, 100% sensitivity (95% CI: 81.32%-100%) and 86.67% specificity (95% CI: 75.40%-94.05%), and also for microscopy detection of eggs in urine samples, 69.23% sensitivity (95% CI: 48.21% -85.63%) and 100% specificity (95% CI: 93.08%-100%). Conclusions/Significance We have developed and evaluated, for the first time, a LAMP assay for detection of S. haematobium DNA in heated pellets from patients´ urine samples using no complicated requirement procedure for DNA extraction. The procedure has been named the Rapid

  11. Schistosomiasis and Soil Transmitted Helminths Distribution in Benin: A Baseline Prevalence Survey in 30 Districts

    PubMed Central

    Boko, Pelagie M.; Ibikounle, Moudachirou; Onzo-Aboki, Ablawa; Tougoue, Jean-Jacques; Sissinto, Yollande; Batcho, Wilfrid; Kinde-Gazard, Dorothe; Kabore, Achille

    2016-01-01

    In 2013, Benin developed strategies to control neglected tropical diseases and one of the first step was the disease mapping of the entire country in order to identify endemic districts of schistosomiasis and soil transmitted helminths (STH). This study was carried out in 30 of the 77 districts of Benin. Of these 30 districts 22 were previously treated for Lymphatic Filariasis (LF) using the Ivermectin and Albendazole combination. In each district, five schools were selected and 50 children aged 8 to 14 years were sampled in each school, making a total of 250 children sampled in the district. The schools were selected mainly according to their proximity to lakes or any bodies of water that were likely to have been used by the children. Samples of faeces and urine were collected from each pupil. Urinary schistosomiasis was identified using the urine filtration technique while STH and intestinal schistosomiasis were identified through the Kato Katz method. Overall a total of 7500 pupils were surveyed across 150 schools with a gender ratio of 1:1. Hookworm was identified in all 30 districts with a prevalence ranging from 1.2% (95%CI: 0.0–2.5) to 60% (95%CI: 53.9–66.1). Ascaris lumbricoides was detected in 19 districts with a prevalence rate between 1% (95%CI: 0.0–2.2) and 39% (95%CI: 32.9–45.0). In addition to these common STH, Trichuris trichiura, Enterobius vermicularis and Strongyloides stercoralis were found at low prevalence. Only 16 districts were endemic to Schistosoma mansoni, while 29 districts were endemic to S. haematobium. The S. haematobium prevalence ranged from 0.8% (95% CI: 0.0–1.9) to 56% (95% CI: 50.2–62.5) while the prevalence of S. mansoni varied from 0.4% (95%CI: 0.0–1.2) to 46% (95% CI: 39.8–52.2). The 22 districts, where LF was successfully eliminated, still require mass drug administration (MDA) of albendazole indicating that school-based MDA would be needed even after LF elimination in districts co-endemic to LF and STH in

  12. Tools to Support Policy Decisions Related to Treatment Strategies and Surveillance of Schistosomiasis Japonica towards Elimination

    PubMed Central

    Zhou, Xiao-Nong; Xu, Jing; Chen, Hong-Gen; Wang, Tian-Ping; Huang, Xi-Bao; Lin, Dan-Dan; Wang, Qi-Zhi; Tang, Li; Guo, Jia-Gang; Wu, Xiao-Hua; Feng, Ting; Chen, Jia-Xu; Guo, Jian; Chen, Shao-Hong; Li, Hao; Wu, Zhong-Dao; Peeling, Rosanna W.

    2011-01-01

    Background Appropriate diagnostics to monitor disease trends and assess the effectiveness and impact of interventions are essential for guiding treatment strategies at different thresholds of schistosomiasis transmission and for certifying elimination. Field validation of these assays is urgently needed before they can be adopted to support policy decisions of the national programme for control and elimination of schistosomiasis in P.R. China. We compared the efficacy and utility of different immunoassays in guiding control strategies and monitoring the endemic status of S. japonicum infections towards elimination. Methodology/Principal Findings A cross-sectional survey was conducted in seven villages with different transmission intensities settings to assess the performance and utility of three immunoassays, e.g., an indirect hemagglutination assay (IHA_JX), an enzyme linked immunosorbent assay (ELISA_SZ), and a dot immunogold filtration assay (DIGFA_SH). 6,248 individuals aged 6–65 years old who gave consent and supplied their stool and blood samples were included for data analysis. Results showed that ELISA_SZ performed significantly higher sensitivity (95.45%, 95%CI: 92.94–97.97%) than IHA_JX (87.59%, 95%CI: 83.51–91.49%) and DIGFA_SH (79.55%, 95%CI: 74.68–84.41%), especially in subgroups with very low infection intensity. The specificity of ELISA_SZ, IHA_JX, DIGFA_SH in 6–9 year olds with occasional exposure was nearly 90%. DIGFA_SH performed the highest screening efficacy for patients among three assays with overall positive predicative value of 13.07% (95%CI: 11.42–14.72%). We found a positive correlation of antibody positive rate of IHA_JX with results of stool examination in age strata (r = 0.70, P<0.001). Seropositivity of IHA_JX in children aged 6–9 years old showed an excellent correlation with prevalence of schistosome infection in the seven communities (r = 0.77, P<0.05). Conclusions/Significance Studies suggest that ELISA

  13. [Historical aspects of the risk factors of Schistosoma intercalatum schistosomiasis].

    PubMed

    Jusot, J F; Simarro, P; De Muynck, A

    1996-01-01

    Bilharziosis is a considerable public health problem. It is caused by many species of schistosoma, four of which have wide geographical distribution: Schistosoma mansoni, S. haematobium, S. japonicum and S. intercalatum. The recently discovered S. intercalatum is limited to central and west Africa. Its spread is progressive and its pathogenicity is not completely known. S. intercalatum bilharziosis is usually manifested in the form of dysentery. The physiopathologic explanation of this clinical manifestation is less clear. Immunopathologically, the formation of an inflammatory granuloma constitutes the origin of its symptoms. This is due to many biological factors including delayed hypersensitivity reactions. All cellular immunity changes will facilitate the appearance of symptoms. Our aim has been to show the importance of malnutrition as a pathogenic factor of S. intercalatum bilharziosis. The initial research hypothesis was as follows: malnutrition plays a role in the evolution of a patient from an asymptomatic state of infection to a symptomatic state of illness. We carried out the study in the suburbs of Bata, in Equatorial Guinea. The inhabitants of Ncolombong, essentially rural immigrants, comprised our study population. Following their consent, we recruited individuals less than 45 years of age who had not taken praziquantel during the last 12 months. We included a total of 297 patients. Our study was a case-control, matching on sex and age. A case was defined as an infected patient with acute or chronic diarrhea occurring within the last month' preceding the stool sample analysis. All cases were retained after exhaustive screening of the study population. Each case (group 1) was matched with one or several asymptomatic infected patients (group 2) and two or several asymptomatic noninfected patients chosen at random (group 3). The definition of malnutrition was as follows: weight/height < or = 90% for children less than 15 years of age or weight/height < or

  14. Towards the Elimination of Schistosomiasis japonica through Control of the Disease in Domestic Animals in The People's Republic of China: A Tale of over 60Years.

    PubMed

    Cao, Z-G; Zhao, Y-E; Lee Willingham, A; Wang, T-P

    2016-01-01

    Schistosomiasis japonica, an endemic, zoonotic tropical parasitic disease caused by Schistosoma japonicum, remains an important public health concern in The People's Republic of China. Unlike other species of Schistosoma, over 40 species of wild and domestic animals can act as reservoir hosts of S. japonicum, which increases the difficulty for the control of this tropical disease. It is widely recognized that domestic animals, particularly water buffaloes and cattle, play an important role in the transmission of S. japonicum. Hence, since the 1950s when The People's Republic of China commenced fight against the disease, the control of animal schistosomiasis has been carried out almost synchronously with that of human schistosomiasis, such that great strides have been made over the past six decades. In this chapter, we review the history and current status of schistosomiasis control in domestic animals in The People's Republic of China. We thoroughly analyse the prevalence of domestic animal schistosomiasis at different stages of schistosomiasis control and the role of different species of domestic animals in transmission of the disease, summarize the control strategies and assess their effectiveness. Furthermore, the challenges ahead are discussed and recommendations for future direction are provided.

  15. Synthesis of angiotensins by cultured granuloma macrophages in murine schistosomiasis mansoni

    SciTech Connect

    Weinstock, J.V.; Blum, A.M.

    1986-03-01

    Components of the angiotensin system are present in granulomas of murine schistosomiasis mansoni. Angiotensins may have immunoregulatory function. Granuloma macrophages cultured for up to 3 days generated substantial angiotensin I (AI) and angiotensin II (AII) which appeared in the culture supernatants. Macrophage monolayers were incubated with (/sup 3/H) amino acids, and culture supernatants were extracted with acetone and analyzed by HPLC. Radiolabeled products eluded at times corresponding to those of authentic angiotensins. Immunoadsorption of angiotensins with angiotensin antisera removed reputed radiolabeled angiotensins from the supernatants. Treatment of the elution fraction corresponding to that of authentic AI with angiotensin converting enzyme resulted in the generation of radiolabeled polypeptides which co-eluted with authentic AII and His-Leu. Similar experiments conducted with nonadherent granuloma cells devoid of macrophages failed to demonstrate angiotensin production. These results suggest that granuloma macrophages can synthesize angiotensin.

  16. A Rationale for Schistosomiasis Control in Elementary Schools of the Rainforest Zone of Pernambuco, Brazil

    PubMed Central

    Favre, Tereza C.; Pereira, Ana P. B.; Galvão, Aline F.; Zani, Luciana C.; Barbosa, Constança S.; Pieri, Otávio S.

    2009-01-01

    Background 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. Methodology/Principal Findings 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

  17. Portal vein thrombosis associated with protein C deficiency and elevated Factor VIII in hepatosplenic schistosomiasis.

    PubMed

    Leite, Luiz Arthur Calheiros; Ferreira, Rita de Cássia dos Santos; Hatzlhofer, Betânia Lucena Domingues; Correia, Maria Conceição Barros; Bandeira, Ângela Pontes; Owen, James Stuart; Lima, Vera Lúcia de Menezes; Domingues, Ana Lúcia Coutinho; Lopes, Edmundo Pessoa

    2016-03-01

    Portal vein thrombosis is considered a vaso-occlusive process that can appear during the course of hepatosplenic Schistosoma mansoni, but may result from impaired portal blood flow or be associated with acquired or inherited thrombophilic factors. Here, we report the case of a 67-year-old woman who developed thrombocytopenia as a result of hypersplenism. Following the diagnosis of hepatosplenic schistosomiasis, portal vein thrombosis was detected by ultrasound examination, while haematological tests revealed low levels of protein C (43.3%) and high levels of factor VIII (183.1%). The pathogenesis of portal vein thrombosis remains unclear in some patients with S. mansoni. We recommend, therefore, that early clinical and haemostatic investigations are done to evaluate risk of portal vein thrombosis and hence avoid further complications.

  18. A protocol for geographically randomized snail surveys in schistosomiasis fieldwork using the global positioning system.

    PubMed

    Seto, E; Liang, S; Qiu, D; Gu, X; Spear, R C

    2001-01-01

    A protocol was created for performing geographically randomized snail surveys for schistosomiasis research using the global positioning system (GPS). This protocol differs from traditional surveys in its ability to accurately map and measure the spatial distribution of snail habitat. The protocol was used to map irrigation ditches, the primary habitat for Oncomelania hupensis, in two residence areas in Sichuan Province, China. From the 7,450 meters of mapped ditches, snail surveys were performed at 203 random sites along the ditch network. Of these, 116 (57.1%) sites had snails. The total number of living snails captured was 2,014, resulting in an average snail density of 0.27 snails per linear meter of potential habitat.

  19. Independent Peer Reviews

    SciTech Connect

    2012-03-16

    Independent Assessments: DOE's Systems Integrator convenes independent technical reviews to gauge progress toward meeting specific technical targets and to provide technical information necessary for key decisions.

  20. Cytokine patterns in experimental schistosomiasis mansoni infected mice treated with silymarin.

    PubMed

    El-Sayed, Nagwa Mostafa; Fathy, Ghada Mahmoud; Abdel-Rahman, Sara Abdel-Rahman; El-Shafei, Mahmoud Abdel-Atei

    2016-09-01

    The purpose of this study was to determine cytokine patterns in experimental schistosomiasis mansoni infected mice treated with silymarin. The study was conducted upon 100 mice that were divided into five groups; 20 each: uninfected control group, Schistosoma mansoni infected untreated mice (infected control), infected mice treated with praziquantel (PZQ), infected mice treated with silymarin and infected mice treated with both praziquantel and silymarin. 10 mice from each group were sacrificed at 10th and 18th weeks post infection respectively. Histopathological investigations were performed. Liver sections were stained with hematoxylin-eosin and Masson's trichrome stain to evaluate changes of granuloma sizes and numbers. Serum levels of the cytokines (TNF-α, IFN-γ, IL-4 and TGF-β1) were assessed in the sera of all groups by immunoassay. The measured levels of cytokines (IFN-γ, IL-4, TNF-α, TGF-β1) were found to be significantly increased in infected mice compared to normal control. At the same time, treated groups with silymarin alone or combined with PZQ showed significant decrease in IL-4, TNF-α and TGF-β1 levels compared to infected control. On the other hand, there was a significant increase in IFN-γ level observed in all treated groups compared to infected control. In addition, the histopathological examination of the liver in the group treated with PZQ showed a reduction in the number of livers eggs granuloma at all periods of sacrification compared with the infected untreated group. However, there was more decrease in granulomas diameter in both silymarin treated group or combined with PZQ at all periods of sacrification when compared to infected untreated group. In conclusion; treatment with silymarin combined with PZQ in murine schistosomiasis could reduce hepatic fibrosis by their action on the production of pro-inflammatory cytokines.

  1. Partial Regulatory T Cell Depletion Prior to Schistosomiasis Vaccination Does Not Enhance the Protection

    PubMed Central

    Zhou, Sha; Xu, Zhipeng; Hoellwarth, Jason; Chen, Xiaojun; He, Lei; Zhang, Rongbo; Liu, Feng; Wang, Jun; Su, Chuan

    2012-01-01

    CD4+CD25+ regulatory T cells (Tregs) do not only influence self-antigen specific immune responses, but also dampen the protective effect induced by a number of vaccines. The impact of CD4+CD25+ Tregs on vaccines against schistosomiasis, a neglected tropical disease that is a major public health concern, however, has not been examined. In this study, a DNA vaccine encoding a 26 kDa glutathione S-transferase of Schistosoma japonicum (pVAX1-Sj26GST) was constructed and its potential effects were evaluated by depleting CD25+ cells prior to pVAX1-Sj26GST immunization. This work shows that removal of CD25+ cells prior to immunization with the pVAX1-Sj26GST schistosomiasis DNA vaccine significantly increases the proliferation of splenocytes and IgG levels. However, CD25+ cell-depleted mice immunized with pVAX1-Sj26GST show no improved protection against S. japonicum. Furthermore, depletion of CD25+ cells causes an increase in both pro-inflammatory cytokines (e.g. IFN-γ, GM-CSF and IL-4) and an anti-inflammatory cytokine (e.g. IL-10), with CD4+CD25- T cells being one of the major sources of both IFN-γ and IL-10. These findings indicate that partial CD25+ cell depletion fails to enhance the effectiveness of the schistosome vaccine, possibly due to IL-10 production by CD4+CD25- T cells, or other cell types, after CD25+ cell depletion during vaccination. PMID:22802961

  2. Evaluating the Effect of a Novel Molluscicide in the Endemic Schistosomiasis Japonica Area of China

    PubMed Central

    Xia, Jing; Yuan, Yi; Xu, Xingjian; Wei, Fenghua; Li, Guiling; Liu, Min; Li, Jianqiang; Chen, Rujuan; Zhou, Zhengping; Nie, Shaofa

    2014-01-01

    Oncomelania hupensis is the sole intermediate host snail of Schistosoma japonicum in China. Snail control by molluscicide remains one of the most effective measures of schistosomiasis japonica control. A 50% wettable powder of niclosamide ethanolamine salt (WPN) is widely used for snail control in China. However, WPN is costly and toxic to fish. A novel molluscicide named LDS, the salt of quinoid-2′, 5-dichloro-4′-nitrosalicylanilide from niclosamide, has been developed. To evaluate the effects of large-scale field application of LDS on field snail control, tests were conducted in 15 counties of Hubei Province, China. Active adult snails, were immersed in 0.2, 0.4, and 0.6 g/m3 of 10% LDS, 1.0 g/m3 of 50% WPN was used as the molluscicide control, and then the mortality rates of snails were investigated after 1, 2, and 3 days. In addition, four active concentrations of 10% LDS (0.4, 0.6, 0.8 and 1.0 g/m2) were applied by spraying and powdering in the field. 1.0 g/m2 of 50% WPN was used as the molluscicide control, and then the mortality rates of snails were observed after 1, 3, and 7 days. The results indicated that 0.4 g/m3 LDS applied by the immersion or 0.6 g/m2 LDS applied by spraying and powdering achieved the same molluscicidal effect as that of WPN, regardless of exposure time. By using different methods, the snail mortality rates in the molluscicide groups were related to exposure time and concentration, respectively. LDS costs less than WPN; thus, LDS is suitable and applicable for use as a molluscicide in schistosomiasis japonica epidemic areas. PMID:25310539

  3. Schistosomiasis in school-age children in Burkina Faso after a decade of preventive chemotherapy

    PubMed Central

    Ouedraogo, Hamado; Drabo, François; Zongo, Dramane; Bagayan, Mohamed; Bamba, Issouf; Pima, Tiba; Yago-Wienne, Fanny; Toubali, Emily

    2016-01-01

    Abstract Objective To assess the impact of a decade of biennial mass administration of praziquantel on schistosomiasis in school-age children in Burkina Faso. Methods In 2013, in a national assessment based on 22 sentinel sites, 3514 school children aged 7–11 years were checked for Schistosoma haematobium and Schistosoma mansoni infection by the examination of urine and stool samples, respectively. We analysed the observed prevalence and intensity of infections and compared these with the relevant results of earlier surveys in Burkina Faso. Findings S. haematobium was detected in 287/3514 school children (adjusted prevalence: 8.76%, range across sentinel sites: 0.0–56.3%; median: 2.5%). The prevalence of S. haematobium infection was higher in the children from the Centre-Est, Est and Sahel regions than in those from Burkina Faso’s other eight regions with sentinel sites (P < 0.001). The adjusted arithmetic mean intensity of S. haematobium infection, among all children, was 6.0 eggs per 10 ml urine. Less than 1% of the children in six regions had heavy S. haematobium infections – i.e. at least 50 eggs per 10 ml urine – but such infections were detected in 8.75% (28/320) and 11.56% (37/320) of the children from the Centre-Est and Sahel regions, respectively. Schistosoma mansoni was only detected in two regions and 43 children – i.e. 1 (0.31%) of the 320 from Centre-Sud and 42 (8.75%) of the 480 from Hauts Bassins. Conclusion By mass use of preventive chemotherapy, Burkina Faso may have eliminated schistosomiasis as a public health problem in eight regions and controlled schistosome-related morbidity in another three regions. PMID:26769995

  4. Indicators of improved water access in the context of schistosomiasis transmission in rural Eastern Region, Ghana.

    PubMed

    Kulinkina, Alexandra V; Kosinski, Karen C; Plummer, Jeanine D; Durant, John L; Bosompem, Kwabena M; Adjei, Michael N; Griffiths, Jeffrey K; Gute, David M; Naumova, Elena N

    2017-02-01

    Populations with poor access to water, sanitation and hygiene (WASH) infrastructure are disproportionately affected by the neglected tropical diseases (NTDs). As a result, WASH has gained increasing prominence in integrated control and elimination of NTDs, including schistosomiasis. In order to identify underserved populations, relevant measures of access to WASH infrastructure at sub-national or local levels are needed. We conducted a field survey of all public water sources in 74 rural communities in the Eastern Region of Ghana and computed indicators of water access using two methods: one based on the design capacity and another on the spatial distribution of water sources. The spatial method was applied to improved and surface water sources. According to the spatial method, improved water sources in the study area were well-distributed within communities with 95% (CI95%: 91, 98) of the population having access within 500m when all, and 87% (CI95%: 81, 93) when only functional water sources were considered. According to the design capacity-based method, indicator values were lower: 63% (CI95%: 57, 69) for all and 49% (CI95%: 43, 55) for only functional sources. Surface water access was substantial with 62% (CI95%: 54, 71) of the population located within 500m of a perennial surface water source. A negative relationship was observed between functional improved water access and surface water access within 300m. In this context, perceived water quality of the improved sources was also important, with a 17% increase in surface water access in towns with one reported water quality problem as compared to towns with no problems. Our study offers a potential methodology to use water point mapping data to identify communities in need of improved water access to achieve schistosomiasis risk reduction.

  5. Geographic information systems as a tool for control program management for schistosomiasis in Egypt.

    PubMed

    Abdel-Rahman, M S; El-Bahy, M M; Malone, J B; Thompson, R A; El Bahy, N M

    2001-04-27

    During a 4-year study a geographic information system (GIS) risk model was constructed for predicting the relative risk of schistosomiasis in Kafr El-Sheikh governorate, Egypt. A 1-year 1990-1991 time series on diurnal temperature difference (dT) prepared from the advanced very high resolution radiometer (AVHRR) sensor on the NOAA-11 satellite was used to develop a regional risk model for the Nile delta based on thermal-hydrological domains. A May 15, 1990 Landsat TM scene (path 177, Row 38) was used to develop a local 'village-scale' environmental risk model based on higher resolution satellite sensor data (30 m picture element size at earth surface). Four of ten classes derived from a tasseled cap (Tcap) transformation of the Landsat TM scene were shown to be significantly related to a 5-year Schistosoma mansoni prevalence database from the Ministry of Health. A risk model was developed based on dT and the proportional area of the four Tcap classes in 5 km(2) buffer zones centered on rural health unit (RHU) reporting units. Available historical data on S. mansoni and its snail host Biomphalaria alexandrina, as well as recent field collected data were gathered and incorporated as separate themes. Model validation was done using data collected on snail population bionomics-infection rates, water quality, underground water table and cercariometry at 13 hydrologically representative sites. The role of soil type, water table and water quality was studied at 79 of 154 rural health unit sites. The model permitted retrieval of relevant data by RHU point location. For the first time in Egypt, the Kafr El-Sheikh GIS schistosoma prediction model can support MOH efforts to make more accurate control program decisions based on environmental predilection sites of endemic Schistosomiasis mansoni.

  6. Research on Dynamic Monitoring (1990-2010) of Schistosomiasis Vector-Snail at Xinmin Beach, Gaoyou Lake, Jiangsu Province, China

    NASA Astrophysics Data System (ADS)

    Liu, Zhaoyan; Li, Chuanrong; Tang, Lingli; Zhou, Xiaonong; Ma, Lingling

    2014-11-01

    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 (snail) is the unique intermediate host of schistosoma, so monitoring and controlling of the number of snail is key to reduce the risk of schistosomiasis transmission. Remote sensing technology can real-timely access the large-scale environmental factors related to snail breeding and reproduction, and can also provide the efficient information to determine the location, area, and spread tendency of snail. Based on the T-S (Takagi-Sugeno) fuzzy information theory, a quantitative remote sensing monitoring model of snail has been developed in previous wok. In a case study, this paper will take Xinmin beach, Gaoyou Lake as new research area, carry out 20 years (1990 - 2010) dynamic monitoring, to further validate the effectiveness of the T-S Fuzzy RS snail monitoring model.

  7. Research on Dynamic Monitoring (1990-2010)of Schistosomiasis Vector- Snail at Xinmin Beach, Gaoyou Lake, Jiangsu Province, China

    NASA Astrophysics Data System (ADS)

    Liu, Zhaoyan; Li, Chuanrong; Tang, Lingli; Zhou, Xiaonong; Ma, Lingling

    2014-11-01

    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 (snail) is the unique intermediate host of schistosoma, so monitoring and controlling of the number of snail is key to reduce the risk of schistosomiasis transmission. Remote sensing technology can real-timely access the large-scale environmental factors related to snail breeding and reproduction, and can also provide the efficient information to determine the location, area, and spread tendency of snail. Based on the T-S (Takagi-Sugeno) fuzzy information theory, a quantitative remote sensing monitoring model of snail has been developed in previous wok. In a case study, this paper will take Xinmin beach, Gaoyou Lake as new research area, carry out 20 years (1990 - 2010) dynamic monitoring, to further validate the effectiveness of the T-S Fuzzy RS snail monitoring model.

  8. From Schistosomiasis Vector Habitats Identification to Human Transmission Risk Mapping, in the Poyang Lake Area (Jiangxi Province, PR China)

    NASA Astrophysics Data System (ADS)

    Marie, T.; Huber, C.; Yesou, H.

    2013-01-01

    Schistosomiasis (Bilharzias) is the most frequent disease after malaria in the world. This disease hit 200 million people, and threats 600 million people. In China, Schistosomiasis japonicum, a serious communicable parasitic disease, is endemic along the Yangtze River basin, including monsoon lakes. Risky transmission areas are conditioned by the S. japonicum vector’s presence and human activities and presence. On Poyang Lake, marshlands are the principal area of its development. The aim of this work is to answer : Where are areas suitable for vector’s disease development ? Where and what are the human activities the most exposed to disease transmission ? Where are urban areas with the higher level of disease transmission risk ? How data crossing can be useful for identification of areas with the higher transmission risk level ?

  9. Human schistosomiasis

    PubMed Central

    Colley, Daniel G; Bustinduy, Amaya L; Secor, W Evan; King, Charles H

    2015-01-01

    Human schistosomiasis—or bilharzia—is a parasitic disease caused by trematode flukes of the genus Schistosoma. By conservative estimates, at least 230 million people worldwide are infected with Schistosoma spp. Adult schistosome worms colonise human blood vessels for years, successfully evading the immune system while excreting hundreds to thousands of eggs daily, which must either leave the body in excreta or become trapped in nearby tissues. Trapped eggs induce a distinct immune-mediated granulomatous response that causes local and systemic pathological effects ranging from anaemia, growth stunting, impaired cognition, and decreased physical fitness, to organ-specific effects such as severe hepatosplenism, periportal fibrosis with portal hypertension, and urogenital inflammation and scarring. At present, preventive public health measures in endemic regions consist of treatment once every 1 or 2 years with the isoquinolinone drug, praziquantel, to suppress morbidity. In some locations, elimination of transmission is now the goal; however, more sensitive diagnostics are needed in both the field and clinics, and integrated environmental and health-care management will be needed to ensure elimination. PMID:24698483

  10. Chemotherapeutic Studies on Schistosomiasis and Clinical Epidemiological and Immunological Studies on Malaria in Amazonas, Brazil, along the Ituxi River.

    DTIC Science & Technology

    1981-09-01

    fi76 341 CHEMOTHERAPEUTIC STUDIES ON SCHISTOSONIRSIS AND 1/1 CLINICAL EPIDENIOLOGICAL A.. (U) BRASILIA UNIV ( BRAZIL ) A R PRATA ET AL SEP 81 DAMDi7...Fort Derick, Frederick, Maryland 21701-5012 Grant No. DAMDl7-80-G-9479 University of Brasilia Brasilia, D.F., Brazil Approved for public release...ON SCHISTOSOMIASIS AND Annual/Final CLINICAL, EPIDEMIOLOGICAL AND IMMUNOLOGICAL Oct 80-Sep 81 STUDTES ON MALAIA IN AMAZONAS, BRAZIL , ALONG THE 6

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

    PubMed Central

    Oliveira, Suellen D'arc Santos; Nanini, Hayandra Ferreira; Savio, Luiz Eduardo Baggio; Waghabi, Mariana Caldas; Silva, Claudia Lucia Martins

    2014-01-01

    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. PMID:25276050

  12. Implications of Changing Temperatures on the Growth, Fecundity and Survival of Intermediate Host Snails of Schistosomiasis: A Systematic Review

    PubMed Central

    Kalinda, Chester; Chimbari, Moses; Mukaratirwa, Samson

    2017-01-01

    Climate change has been predicted to increase the global mean temperature and to alter the ecological interactions among organisms. These changes may play critical roles in influencing the life history traits of the intermediate hosts (IHs). This review focused on studies and disease models that evaluate the potential effect of temperature rise on the ecology of IH snails and the development of parasites within them. The main focus was on IH snails of schistosome parasites that cause schistosomiasis in humans. A literature search was conducted on Google Scholar, EBSCOhost and PubMed databases using predefined medical subject heading terms, Boolean operators and truncation symbols in combinations with direct key words. The final synthesis included nineteen published articles. The studies reviewed indicated that temperature rise may alter the distribution, optimal conditions for breeding, growth and survival of IH snails which may eventually increase the spread and/or transmission of schistosomiasis. The literature also confirmed that the life history traits of IH snails and their interaction with the schistosome parasites are affected by temperature and hence a change in climate may have profound outcomes on the population size of snails, parasite density and disease epidemiology. We concluded that understanding the impact of temperature on the growth, fecundity and survival of IH snails may broaden the knowledge on the possible effects of climate change and hence inform schistosomiasis control programmes. PMID:28098789

  13. Water level regulation and control of schistosomiasis transmission: a case study in Oyan Reservoir, Ogun State, Nigeria.

    PubMed

    Ofoezie, I E; Asaolu, S O

    1997-01-01

    The effect of different water discharge patterns from the artificial Oyan Reservoir in Ogun State, Nigeria, on water level fluctuations and on schistosomiasis transmission was investigated between August 1990 and March 1993 to determine the impact of water level regulation on schistosomiasis transmission and control. The results show that transmission was greatly influenced by the pattern of water discharge during the hot dry season (January-April). A high discharge during this period of no rainfall, high temperatures, and intense sunshine stimulated rapid water level fluctuations and lake draw-down, which led to significant reductions in all indices of schistosomiasis transmission, i.e. snail density, snail infection rates, human water contact patterns, and incidence of infection. Although these results support continuous water discharges from the reservoir during the hot dry season, this may run counter to current water management policies. Further investigation is therefore required to harmonize the potential benefits in this type of discharge pattern with the objectives of efficient water management in artificial reservoirs.

  14. Implications of Changing Temperatures on the Growth, Fecundity and Survival of Intermediate Host Snails of Schistosomiasis: A Systematic Review.

    PubMed

    Kalinda, Chester; Chimbari, Moses; Mukaratirwa, Samson

    2017-01-13

    Climate change has been predicted to increase the global mean temperature and to alter the ecological interactions among organisms. These changes may play critical roles in influencing the life history traits of the intermediate hosts (IHs). This review focused on studies and disease models that evaluate the potential effect of temperature rise on the ecology of IH snails and the development of parasites within them. The main focus was on IH snails of schistosome parasites that cause schistosomiasis in humans. A literature search was conducted on Google Scholar, EBSCOhost and PubMed databases using predefined medical subject heading terms, Boolean operators and truncation symbols in combinations with direct key words. The final synthesis included nineteen published articles. The studies reviewed indicated that temperature rise may alter the distribution, optimal conditions for breeding, growth and survival of IH snails which may eventually increase the spread and/or transmission of schistosomiasis. The literature also confirmed that the life history traits of IH snails and their interaction with the schistosome parasites are affected by temperature and hence a change in climate may have profound outcomes on the population size of snails, parasite density and disease epidemiology. We concluded that understanding the impact of temperature on the growth, fecundity and survival of IH snails may broaden the knowledge on the possible effects of climate change and hence inform schistosomiasis control programmes.

  15. Characteristics of Blood Vessels in Female Genital Schistosomiasis: Paving the Way for Objective Diagnostics at the Point of Care

    PubMed Central

    Holmen, Sigve; Galappaththi-Arachchige, Hashini Nilushika; Kleppa, Elisabeth; Pillay, Pavitra; Naicker, Thajasvarie; Taylor, Myra; Onsrud, Mathias; Kjetland, Eyrun Floerecke; Albregtsen, Fritz

    2016-01-01

    Background The mucosal changes associated with female genital schistosomiasis (FGS) encompass abnormal blood vessels. These have been described as circular, reticular, branched, convoluted and having uneven calibre. However, these characteristics are subjective descriptions and it has not been explored which of them are specific to FGS. Methods In colposcopic images of young women from a schistosomiasis endemic area, we performed computerised morphologic analyses of the cervical vasculature appearing on the mucosal surface. Study participants where the cervix was classified as normal served as negative controls, women with clinically diagnosed FGS and presence of typical abnormal blood vessels visible on the cervical surface served as positive cases. We also included women with cervical inflammatory conditions for reasons other than schistosomiasis. By automating morphological analyses, we explored circular configurations, vascular density, fractal dimensions and fractal lacunarity as parameters of interest. Results We found that the blood vessels typical of FGS are characterised by the presence of circular configurations (p < 0.001), increased vascular density (p = 0.015) and increased local connected fractal dimensions (p = 0.071). Using these features, we were able to correctly classify 78% of the FGS-positive cases with an accuracy of 80%. Conclusions The blood vessels typical of FGS have circular configurations, increased vascular density and increased local connected fractal dimensions. These specific morphological features could be used diagnostically. Combined with colourimetric analyses, this represents a step towards making a diagnostic tool for FGS based on computerised image analysis. PMID:27073857

  16. A call to strengthen the global strategy against schistosomiasis and soil-transmitted helminthiasis: the time is now.

    PubMed

    Lo, Nathan C; Addiss, David G; Hotez, Peter J; King, Charles H; Stothard, J Russell; Evans, Darin S; Colley, Daniel G; Lin, William; Coulibaly, Jean T; Bustinduy, Amaya L; Raso, Giovanna; Bendavid, Eran; Bogoch, Isaac I; Fenwick, Alan; Savioli, Lorenzo; Molyneux, David; Utzinger, Jürg; Andrews, Jason R

    2017-02-01

    In 2001, the World Health Assembly (WHA) passed the landmark WHA 54.19 resolution for global scale-up of mass administration of anthelmintic drugs for morbidity control of schistosomiasis and soil-transmitted helminthiasis, which affect more than 1·5 billion of the world's poorest people. Since then, more than a decade of research and experience has yielded crucial knowledge on the control and elimination of these helminthiases. However, the global strategy has remained largely unchanged since the original 2001 WHA resolution and associated WHO guidelines on preventive chemotherapy. In this Personal View, we highlight recent advances that, taken together, support a call to revise the global strategy and guidelines for preventive chemotherapy and complementary interventions against schistosomiasis and soil-transmitted helminthiasis. These advances include the development of guidance that is specific to goals of morbidity control and elimination of transmission. We quantify the result of forgoing this opportunity by computing the yearly disease burden, mortality, and lost economic productivity associated with maintaining the status quo. Without change, we estimate that the population of sub-Saharan Africa will probably lose 2·3 million disability-adjusted life-years and US$3·5 billion of economic productivity every year, which is comparable to recent acute epidemics, including the 2014 Ebola and 2015 Zika epidemics. We propose that the time is now to strengthen the global strategy to address the substantial disease burden of schistosomiasis and soil-transmitted helminthiasis.

  17. Hydrology and density feedbacks control the ecology of intermediate hosts of schistosomiasis across habitats in seasonal climates.

    PubMed

    Perez-Saez, Javier; Mande, Theophile; Ceperley, Natalie; Bertuzzo, Enrico; Mari, Lorenzo; Gatto, Marino; Rinaldo, Andrea

    2016-06-07

    We report about field and theoretical studies on the ecology of the aquatic snails (Bulinus spp. and Biomphalaria pfeifferi) that serve as obligate intermediate hosts in the complex life cycle of the parasites causing human schistosomiasis. Snail abundance fosters disease transmission, and thus the dynamics of snail populations are critically important for schistosomiasis modeling and control. Here, we single out hydrological drivers and density dependence (or lack of it) of ecological growth rates of local snail populations by contrasting novel ecological and environmental data with various models of host demography. Specifically, we study various natural and man-made habitats across Burkina Faso's highly seasonal climatic zones. Demographic models are ranked through formal model comparison and structural risk minimization. The latter allows us to evaluate the suitability of population models while clarifying the relevant covariates that explain empirical observations of snail abundance under the actual climatic forcings experienced by the various field sites. Our results link quantitatively hydrological drivers to distinct population dynamics through specific density feedbacks, and show that statistical methods based on model averaging provide reliable snail abundance projections. The consistency of our ranking results suggests the use of ad hoc models of snail demography depending on habitat type (e.g., natural vs. man-made) and hydrological characteristics (e.g., ephemeral vs. permanent). Implications for risk mapping and space-time allocation of control measures in schistosomiasis-endemic contexts are discussed.

  18. Gender Difference of Kaposi’s sarcoma-associated Herpesvirus Infection in Population with Schistosomiasis in Rural China

    PubMed Central

    Fu, Bishi; Xia, Fan; Li, Baolin; Ouyang, Xinxing; Gao, Shou-Jiang; Yang, Rongge; Wang, Linding

    2012-01-01

    Summary Kaposi sarcoma-associated herpesvirus (KSHV) is the causal agent of (KS), a common cancer in AIDS patients. The risk factors for KSHV infection have been extensively studied in Western countries but remain largely undefined in other parts of the World. Schistosomiasis caused by infection of Schistosoma japonicum is recently identified as a cofactor for KSHV infection in rural Egypt. In this study, we examined the seroprevalence of KSHV in a population with high incidence of Schistomasis along the Yangtze River in China. The seroprevalence of KSHV is slightly higher in subjects with than without Schistosomiasis but it is not statistically significant (8.4% vs 6.6%, p = 0.204). The seroprevalence of KSHV is significantly higher in female than male subjects (9.3% vs 5.9%, OR: 1.621, 95% CI: 1.084–2.425, p = 0.019). When adjusted for gender, the seroprevalence of KSHV is significantly higher in subjects with than without Schistosomiasis in male subjects (8.4% vs 2.8%, OR: 3.170, 95% CI: 1.501–6.694, p = 0.002). PMID:22814163

  19. Diagnostics for schistosomiasis in Africa and Arabia: a review of present options in control and future needs for elimination.

    PubMed

    Stothard, J Russell; Stanton, Michelle C; Bustinduy, Amaya L; Sousa-Figueiredo, José C; Van Dam, Govert J; Betson, Martha; Waterhouse, David; Ward, Steve; Allan, Fiona; Hassan, Amir A; Al-Helal, Mohammad A; Memish, Ziad A; Rollinson, David

    2014-12-01

    Within the World Health Organization 2012-2020 roadmap for control and elimination of schistosomiasis, the scale-up of mass drug administration with praziquantel is set to change the epidemiological landscape across Africa and Arabia. Central in measuring progress is renewed emphasis upon diagnostics which operate at individual, community and environmental levels by assessing reductions in disease, infections and parasite transmission. However, a fundamental tension is revealed between levels for present diagnostic tools, and methods applied in control settings are not necessarily adequate for application in elimination scenarios. Indeed navigating the transition from control to elimination needs careful consideration and planning. In the present context of control, we review current options for diagnosis of schistosomiasis at different levels, highlighting several strengths and weaknesses therein. Future challenges in elimination are raised and we propose that more cost-effective diagnostics and clinical staging algorithms are needed. Using the Kingdom of Saudi Arabia as a contemporary example, embedding new diagnostic methods within the primary care health system is discussed with reference to both urogenital and intestinal schistosomiasis.

  20. Hydrology and density feedbacks control the ecology of intermediate hosts of schistosomiasis across habitats in seasonal climates

    PubMed Central

    Perez-Saez, Javier; Mande, Theophile; Ceperley, Natalie; Bertuzzo, Enrico; Mari, Lorenzo; Rinaldo, Andrea

    2016-01-01

    We report about field and theoretical studies on the ecology of the aquatic snails (Bulinus spp. and Biomphalaria pfeifferi) that serve as obligate intermediate hosts in the complex life cycle of the parasites causing human schistosomiasis. Snail abundance fosters disease transmission, and thus the dynamics of snail populations are critically important for schistosomiasis modeling and control. Here, we single out hydrological drivers and density dependence (or lack of it) of ecological growth rates of local snail populations by contrasting novel ecological and environmental data with various models of host demography. Specifically, we study various natural and man-made habitats across Burkina Faso’s highly seasonal climatic zones. Demographic models are ranked through formal model comparison and structural risk minimization. The latter allows us to evaluate the suitability of population models while clarifying the relevant covariates that explain empirical observations of snail abundance under the actual climatic forcings experienced by the various field sites. Our results link quantitatively hydrological drivers to distinct population dynamics through specific density feedbacks, and show that statistical methods based on model averaging provide reliable snail abundance projections. The consistency of our ranking results suggests the use of ad hoc models of snail demography depending on habitat type (e.g., natural vs. man-made) and hydrological characteristics (e.g., ephemeral vs. permanent). Implications for risk mapping and space-time allocation of control measures in schistosomiasis-endemic contexts are discussed. PMID:27162339

  1. Schistosomiasis in pre-school-age children and their mothers in Chikhwawa district, Malawi with notes on characterization of schistosomes and snails

    PubMed Central

    2014-01-01

    Background To complement ongoing schistosomiasis control within national control programmes (NCPs) that administer praziquantel to school-age children, assessing the risk and extent of schistosomiasis in pre-school-age children (PSAC) is important. Methods In June 2012, schistosomiasis in Chikhwawa district, Malawi was assessed across 12 villages examining pre-school-age children (PSAC) and their mothers by serological and parasitological diagnosis, as supplemented with urine-antigen and questionnaire-interview methods. Urinary tract morbidity was inferred by haematuria and albuminuria assays. Results In total, 49.5% (CI95 42.6-56.4) of 208 PSAC and 94.5% (CI95 90.9-98.1) of 165 mothers were seropositive for schistosomiasis, in 2 villages seroprevalence exceeded 75% in PSAC. Egg-patent urogenital and intestinal schistosomiasis was observed; 17.7% (CI95 12.4-23.2) of PSAC and 45.1% (CI95 37.4-52.8) of mothers having active schistosomiasis by parasitological and urine-antigen testing combined. PSAC often had extensive daily water contact and many (~25%) had haematuria and albuminuria. As eggs with an atypical morphology of Schistosoma haematobium were observed, a general selection of schistosome eggs was characterized by DNA barcoding, finding Group I S. haematobium and Group IV and V S. mansoni. Malacological surveys encountered several populations of Bulinus globosus but failed to find Biomphalaria. Conclusions Both PSAC and their mothers appear to be at significant risk of schistosomiasis and should be considered for treatment within the NCP of Malawi. PMID:24690282

  2. The secretory mechanisms in equine platelets are independent of cytoskeletal polymerization and occur through membrane fusion.

    PubMed

    Brunso, L; Segura, D; Monreal, L; Escolar, G; White, J G; Diaz-Ricart, M

    2010-01-01

    Studies in animal models are useful to understand the basic mechanisms involved in hemostasis and the functional differences among species. Ultrastructural observations led us to predict differences in the activation and secretion mechanisms between equine and human platelets. The potential mechanisms involved have been comparatively explored in the present study. Equine and human platelets were activated with thrombin (0.5 U/ml) and collagen (20 µg/ml), for 90 seconds, and samples processed to evaluate: i) ultrastructural changes, by electron microscopy, ii) actin polymerization and cytoskeletal assembly, by polyacrylamide gel electrophoresis, and iii) specific molecules involved in activation and secretion, by western blot. In activated human platelets, centralization of granules, cytoskeletal assembly and fusion of granules with the open canalicular system were observed. In activated equine platelets, granules fused together forming an organelle chain that fused with the surface membrane and released its content directly outside the platelets. Human platelets responded to activation with actin polymerization and the assembly of other contractile proteins to the cytoskeleton. These events were almost undetectable in equine platelets. When exploring the involvement of the synaptosomal-associated protein-23 (SNAP-23), a known regulator of secretory granule/plasma membrane fusion events, it was present in both human and equine platelets. SNAP-23 was shown to be more activated in equine platelets than human platelets in response to activation, especially with collagen. Thus, there are significant differences in the secretion mechanisms between human and equine platelets. While in human platelets, activation and secretion of granules depend on mechanisms of internal contraction and membrane fusion, in equine platelets the fusion mechanisms seem to be predominant.

  3. Acute clearance of human metapneumovirus occurs independently of natural killer cells.

    PubMed

    Wen, Sherry C; Tollefson, Sharon J; Johnson, Monika; Gilchuk, Pavlo; Boyd, Kelli L; Shepherd, Bryan; Joyce, Sebastian; Williams, John V

    2014-09-01

    Human metapneumovirus (HMPV) is a major cause of respiratory disease. The role of NK cells in protection against HMPV is unclear. We show that while HMPV-infected C57BL/6 mice had higher numbers of functional lung NK cells than mock-treated mice, comparing NK cell-depleted and control mice did not reveal differences in lung viral titers, histopathology, cytokine levels, or T cell numbers or function. These data indicate that NK cells are not required for host control of HMPV.

  4. Acute suppression of apo B secretion by insulin occurs independently of MTP.

    PubMed

    Sparks, Janet D; Chamberlain, Jeffrey M; O'Dell, Colleen; Khatun, Irani; Hussain, M Mahmood; Sparks, Charles E

    2011-03-11

    Secretion of apolipoprotein (apo) B-containing lipoproteins by the liver depends mainly upon apo B availability and microsomal triglyceride transfer protein (MTP) activity and is subject to insulin regulation. Hepatic MTP mRNA expression is negatively regulated by insulin which correlates with inhibition of apo B secretion suggesting that insulin might suppress apo B secretion through an MTP-dependent mechanism. To investigate this possibility, we examined the acute effect of insulin on hepatic MTP expression and activity levels in vivo utilizing apobec-1(-/-) mice. Insulin did not significantly alter hepatic MTP mRNA levels or lipid transfer activity 2h following injection, but suppressed expression of genes important in gluconeogenesis. To study the specific role of MTP, we expressed human MTP (hMTP) in primary rat hepatocytes using adenoviral gene transfer. Increased expression of hMTP resulted in a 47.6±17.9% increase in total apo B secreted. Incubation of hepatocytes with insulin suppressed apo B secretion by 50.1±10.8% in cells over-expressing hMTP and by 53.0±12.4% in control transfected hepatocytes. Results indicate that even under conditions of increased hepatic apo B secretion mediated by MTP, responsiveness of hepatocytes to insulin to suppress apo B secretion is maintained.

  5. Convulsive seizures from experimental focal cortical dysplasia occur independently of cell misplacement

    PubMed Central

    Hsieh, Lawrence S.; Wen, John H.; Claycomb, Kumiko; Huang, Yuegao; Harrsch, Felicia A.; Naegele, Janice R.; Hyder, Fahmeed; Buchanan, Gordon F.; Bordey, Angelique

    2016-01-01

    Focal cortical dysplasia (FCD), a local malformation of cortical development, is the most common cause of pharmacoresistant epilepsy associated with life-long neurocognitive impairments. It remains unclear whether neuronal misplacement is required for seizure activity. Here we show that dyslamination and white matter heterotopia are not necessary for seizure generation in a murine model of type II FCDs. These experimental FCDs generated by increasing mTOR activity in layer 2/3 neurons of the medial prefrontal cortex are associated with tonic-clonic seizures and a normal survival rate. Preventing all FCD-related defects, including neuronal misplacement and dysmorphogenesis, with rapamycin treatments from birth eliminates seizures, but seizures recur after rapamycin withdrawal. In addition, bypassing neuronal misplacement and heterotopia using inducible vectors do not prevent seizure occurrence. Collectively, data obtained using our new experimental FCD-associated epilepsy suggest that life-long treatment to reduce neuronal dysmorphogenesis is required to suppress seizures in individuals with FCD. PMID:27249187

  6. Primary Macrophage Chemotaxis Induced by Cannabinoid Receptor 2 Agonists Occurs Independently of the CB2 Receptor.

    PubMed

    Taylor, Lewis; Christou, Ivy; Kapellos, Theodore S; Buchan, Alice; Brodermann, Maximillian H; Gianella-Borradori, Matteo; Russell, Angela; Iqbal, Asif J; Greaves, David R

    2015-06-02

    Activation of CB2 has been demonstrated to induce directed immune cell migration. However, the ability of CB2 to act as a chemoattractant receptor in macrophages remains largely unexplored. Using a real-time chemotaxis assay and a panel of chemically diverse and widely used CB2 agonists, we set out to examine whether CB2 modulates primary murine macrophage chemotaxis. We report that of 12 agonists tested, only JWH133, HU308, L-759,656 and L-759,633 acted as macrophage chemoattractants. Surprisingly, neither pharmacological inhibition nor genetic ablation of CB2 had any effect on CB2 agonist-induced macrophage chemotaxis. As chemotaxis was pertussis toxin sensitive in both WT and CB2(-/-) macrophages, we concluded that a non-CB1/CB2, Gi/o-coupled GPCR must be responsible for CB2 agonist-induced macrophage migration. The obvious candidate receptors GPR18 and GPR55 could not mediate JWH133 or HU308-induced cytoskeletal rearrangement or JWH133-induced β-arrestin recruitment in cells transfected with either receptor, demonstrating that neither are the unidentified GPCR. Taken together our results conclusively demonstrate that CB2 is not a chemoattractant receptor for murine macrophages. Furthermore we show for the first time that JWH133, HU308, L-759,656 and L-759,633 have off-target effects of functional consequence in primary cells and we believe that our findings have wide ranging implications for the entire cannabinoid field.

  7. Primary Macrophage Chemotaxis Induced by Cannabinoid Receptor 2 Agonists Occurs Independently of the CB2 Receptor

    PubMed Central

    Taylor, Lewis; Christou, Ivy; Kapellos, Theodore S.; Buchan, Alice; Brodermann, Maximillian H.; Gianella-Borradori, Matteo; Russell, Angela; Iqbal, Asif J.; Greaves, David R.

    2015-01-01

    Activation of CB2 has been demonstrated to induce directed immune cell migration. However, the ability of CB2 to act as a chemoattractant receptor in macrophages remains largely unexplored. Using a real-time chemotaxis assay and a panel of chemically diverse and widely used CB2 agonists, we set out to examine whether CB2 modulates primary murine macrophage chemotaxis. We report that of 12 agonists tested, only JWH133, HU308, L-759,656 and L-759,633 acted as macrophage chemoattractants. Surprisingly, neither pharmacological inhibition nor genetic ablation of CB2 had any effect on CB2 agonist-induced macrophage chemotaxis. As chemotaxis was pertussis toxin sensitive in both WT and CB2-/- macrophages, we concluded that a non-CB1/CB2, Gi/o-coupled GPCR must be responsible for CB2 agonist-induced macrophage migration. The obvious candidate receptors GPR18 and GPR55 could not mediate JWH133 or HU308-induced cytoskeletal rearrangement or JWH133-induced β-arrestin recruitment in cells transfected with either receptor, demonstrating that neither are the unidentified GPCR. Taken together our results conclusively demonstrate that CB2 is not a chemoattractant receptor for murine macrophages. Furthermore we show for the first time that JWH133, HU308, L-759,656 and L-759,633 have off-target effects of functional consequence in primary cells and we believe that our findings have wide ranging implications for the entire cannabinoid field. PMID:26033291

  8. Praziquantel treatment of school children from single and mixed infection foci of intestinal and urogenital schistosomiasis along the Senegal River Basin: monitoring treatment success and re-infection patterns.

    PubMed

    Webster, Bonnie L; Diaw, Oumar T; Seye, Mohmoudane M; Faye, Djibril S; Stothard, J Russell; Sousa-Figueiredo, Jose C; Rollinson, David

    2013-11-01

    Following major water development schemes in the 1980s, schistosomiasis has become a serious parasitic disease of children living in the Senegal River Basin. Both urogenital (Schistosoma haematobium) and intestinal (Schistosoma mansoni) schistosomiasis can be highly prevalent in school-aged children, with many individuals infected with both parasites. In order to investigate the transmission and re-infection dynamics of both parasite species, single and mixed infection foci at three villages (Nder and Temeye; S. mansoni and S. haematobium foci and Guia; S. haematobium focus) were studied. In each focus infected children were identified and selected for a 12-month study involving two treatments with praziquantel (40mg/kg) three weeks apart at the beginning of the study and again 6 months into the study. Urine and stool samples were examined for schistosome eggs before and at 6 weeks and 6 months after chemotherapy. Prevalence and intensity of infection were recorded for each child at each time point. Before treatment, in all three villages, the prevalence and intensity of infection was extremely high for both S. mansoni (79-100%) and S. haematobium (81-97%). With the first round of chemotherapy sufficient cure rates (CRs) of both species were achieved in all villages (38-96%) with high egg reduction rates (ERRs) (97-99%). The data show that high and rapid re-infection rates occur, especially for S. mansoni, within a six-month period following treatment. Re-infection must be highly linked to ecological and seasonal factors. The persistence of S. mansoni in Nder could raise concern as levels of infection intensity remain high (geometric mean intensity at baseline 653epg changed to 705epg at 12 months) after four rounds of chemotherapy. This phenomenon could be explained by extremely rapid re-infection dynamics or a sub-optimal efficacy of praziquantel against S. mansoni in this village. High intensities in mixed infections may influence disease epidemiology and

  9. Systematic Review and Meta-Analysis of Artemisinin Based Therapies for the Treatment and Prevention of Schistosomiasis

    PubMed Central

    Pérez del Villar, Luis; Burguillo, Francisco J.; López-Abán, Julio; Muro, Antonio

    2012-01-01

    Background Chemotherapy based on repeated doses of praziquantel is still the most effective control strategy against Schistosomiasis, however artemisinin derivatives emerged as a family of compounds with schistomicide activity. The aim of the present work is to compare the efficacy of artemisinin-based therapies in the treatment and prophylaxis of human schistosomiasis. The design of this work involved a quantitative systematic review and meta-analysis. Methodology/Principal Findings Retrieval of published studies was carried out through an electronic search of the PubMed (MEDLINE), EMBASE, Cochrane Library and CINAHL databases. This included reports comparing the therapeutic efficacy of artesunate alone, artesunate plus sulfadoxine-pyrimethamine and a combination of artemisinin derivatives plus praziquantel against praziquantel alone on different types of schistosomiasis. Moreover, studies on artesunate and artemether used as preventive drugs were also analyzed against placebo. The primary outcome measure for schistosomiasis treatment was “parasitological cure”, whereas for the prophylaxis the outcome evaluated was “infection rate”. Our results show that patients treated with artesunate alone have significantly lower cure rates than those treated with praziquantel (OR = 0.27 (95% C.I. 0.13–0.53; p<0.001)) and that the combined therapy of artesunate plus sulfadoxine-pyrimethamine is also significantly less effective than praziquantel treatment (OR = 0.14 (95% C.I. 0.02–0.92; p = 0.04)). However, the combination of an artemisinin derivatives plus praziquantel showed a higher cure rate than praziquantel monotherapy with OR = 2.07 (95% C.I. 1.27–3.36; p = 0.003). Finally, chemoprophylaxis with either artesunate (RR = 0.11 (95% C.I. 0.06–0.22; p<0.001)) or artemether (RR = 0.25 (95% C.I. 0.16–0.40; p<0.001)) was significantly better than a placebo in both cases. Conclusions/Significance This meta-analysis confirms that

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

    PubMed

    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

  11. Epidemiology of Schistosomiasis and Usefulness of Indirect Diagnostic Tests in School-Age Children in Cubal, Central Angola

    PubMed Central

    Bocanegra, Cristina; Gallego, Sara; Mendioroz, Jacobo; Moreno, Milagros; Sulleiro, Elena; Salvador, Fernando; Sikaleta, Nicolau; Nindia, Arlette; Tchipita, Daniel; Joromba, Morais; Kavaya, Sebastiao; Sánchez Montalvá, Adrián; López, Teresa; Molina, Israel

    2015-01-01

    Introduction Schistosomiasis remains a public health major problem and little is known in many areas, mainly in Sub-Saharan Africa Objectives To assess the burden and risk factors of schistosomiasis and intestinal parasitic helminthes in the children of Cubal, Angola, and to compare different diagnostic approaches for urinary schistosomiasis under field conditions. Methods A cross-sectional study was conducted. Urine and faeces samples of school children were microscopically studied. A random sample of children was obtained from an alphabetically arranged list of children, taking one of two children. Urine dipstick, colorimetric test and macrohaematuria were considered as indirect diagnostic methods and compared to direct urine examination. Possible risk factors for the infection were sex, age, distance to the river and previous treatment with praziquantel; the assessment was performed using Chi-square test. Results A total of 785 (61.18%) children showed S. haematobium eggs in urine; children living within 500 meters from the river had a higher odds for infection: Odds ratio 1.97 (1.45–2.7 CI 95%); urine dipstick showed sensitivity of 96% and specificity of 61.3%, with a positive predictive value; colorimetric test showed sensitivity of 52.5%, specificity of 74.6% and a positive predictive value of 77%. Proteinuria was present in 653 (51.1%) children, being more frequent in children with S. haematobium in urine (75.2%); 32 of 191 stool samples (16%) showed the presence of other intestinal parasites and 8 (4%) for S. haematobium. Conclusions Prevalence of urinary schistosomiasis in our study area is much higher than the national average, considering it as a high-risk community. Proximity to a source of water was a risk factor for the infection. Indirect tests, as urine dipstick and colorimetric test, were useful tools for diagnosis, due to ease of use and low cost. Proteinuria was a common finding, probably showing an early structural damage due to

  12. The Three Gorges Dam: Does it accelerate or delay the progress towards eliminating transmission of schistosomiasis in China?

    PubMed

    Zhou, Yi-Biao; Liang, Song; Chen, Yue; Jiang, Qing-Wu

    2016-07-05

    The Three Gorges Dam, located in the largest endemic area of schistosomiasis in China, is one of the world's largest hydroelectric projects to date. Some large-scale hydro projects have resulted in schistosomiasis emergence or re-emergence. Therefore, the dam's potential impact on the transmission of Schistosoma japonicum has raised concerns from medical researchers worldwide. A systematic literature review, coupled with an analysis of data on the water level and snail density in the Yangtze River was conducted to assess the impact of the dam on schistosomiasis transmission after more than 10 years of operation. The dam has significantly altered the water levels in the Yangtze River according to different seasons. These changes directly impact the ecology of the schistosome snail host. Due to the dam, there has been a reduction in the density of Oncomelania snails and/or changes in the distribution of snails. The prevalence of infection with S. japonicum has decreased in the downstream areas of the dam, including in the Dongting and Poyang Lakes. The prevalence of infection with S. japonicum in humans has decreased from 6.80 % in 2002 (before the dam began operating) to 0.50 % in 2012, and the number of people infected with S. japonicum have decreased from 94 208 in 2002 to 59 200 in 2011 in the Poyang Lake region. The presence of the dam does not seem to affect snail breeding or the prevalence of schistosomiasis in the Three Gorges Reservoir. Overall, the Three Gorges Dam has significantly contributed to changes in hydrology after more than 10 years of the dam operating. The changes caused by the dam, together with integrated control of schistosomiasis, might be accelerating the progress towards eliminating the transmission of S. japonicum in the middle and lower reaches of the Yangtze River. Despite the positive effect the dam is having in controlling S. japonicum transmission, continued surveillance is required to monitor the future ecological impacts of the

  13. Comparative analysis of knowledge on schistosomiasis japonica in the local people in the former endemic area in Yamanashi Prefecture, Japan: comparisons among the background of age and occupation

    PubMed Central

    HATA, Nobuhide; YASUKAWA, Akio; SEI, Eiichi; KAWASUMI, Koh; MIYA, Naoto; YAMAGUCHI, Hironobu; MINAI, Masaru; SHIMOGAWARA, Rieko; OHTA, Nobuo

    2017-01-01

    Eradication of schistosomiasis japonica in Yamanashi Prefecture was officially declared in 1996, and all surveillance and health campaign were finished by the end of 2001. Schistosomiasis control had been carried out by strong collaboration among local Government, local people and academia, thought which knowledge and experiences of the disease control were accumulated among the local people. It is 20th anniversary of the disease eradication in Yamanashi. We planned to analyze the current situation whether the local people still keep the knowledge of schistosomiasis or not. There was no more knowledge kept in the middle school students, to whom the local Government did not educate about schistosomiasis. Among adult individuals, elderly people who have experienced endemic condition still know about it at almost comparable level as in the past. However, younger people who learned it in the primary school but no experience of the disease transmission started losing the knowledge. Those situations of the adult local people were compared with the veterinarian group. It was confirmed that the veterinarian group had correct and proper knowledge of schistosomiasis japonica not only in elderly groups, but also in younger age group. Considering that methods for control and prevention of infectious diseases are common to some extent, their knowledge and experiences would be applicable for other infectious diseases in future. Therefore, the knowledge would be worth keeping in the local people. Taken together, individuals with specialty, such as veterinarians, are expected to play roles in public health for promotion of health and welfare. PMID:28111404

  14. Evaluation of the use of C-terminal part of the Schistosoma mansoni 200kDa tegumental protein in schistosomiasis diagnosis and vaccine formulation.

    PubMed

    Carvalho, Gardênia Braz Figueiredo de; Pacífico, Lucila Gonçalves Grossi; Pimenta, Deborah Laranjeira Ferreira; Siqueira, Liliane Maria Vidal; Teixeira-Carvalho, Andréa; Coelho, Paulo Marcos Zech; Pinheiro, Carina da Silva; Fujiwara, Ricardo Toshio; Oliveira, Sergio Costa; Fonseca, Cristina Toscano

    2014-04-01

    Schistosoma mansoni tegument is involved in essential functions for parasite survival and represents a target for screening candidates for vaccine and diagnosis. Our group using reverse vaccinology selected six candidates, previously demonstrated by proteomics studies to be expressed in the parasite tegument, among them was Sm200. In this work we have cloned and expressed a recombinant form of Sm200 C-terminal (1069-1520) region. The efficacy of rSm200 (1069-1520) in the diagnosis of schistosomiasis and in the formulation of a vaccine against S. mansoni was assessed respectively in an ELISA based diagnostic assay and immunization protocols in mice. Significant differences between non-infected and acutely infected or chronically infected animals were observed and no cross-recognition was observed with sera from Ascaris suum or Ancylostoma ceylanicum infected mice. rSm200-ELISA test could also discriminate infected individuals from healthy donors not living in endemic area for schistosomiasis but failed to discriminate between individuals from a low endemic area for schistosomiasis known to have positive or negative stools after examination. Recombinant Sm200 also failed to induce protection against schistosomiasis, demonstrating that the C-terminal part of Sm200 is unable to induce protective immune response in mice. Therefore rSm200 (1069-1520)-ELISA represents an important tool to be used in the diagnosis of schistosomiasis.

  15. Comparative analysis of knowledge on schistosomiasis japonica in the local people in the former endemic area in Yamanashi Prefecture, Japan: comparisons among the background of age and occupation.

    PubMed

    Hata, Nobuhide; Yasukawa, Akio; Sei, Eiichi; Kawasumi, Koh; Miya, Naoto; Yamaguchi, Hironobu; Minai, Masaru; Shimogawara, Rieko; Ohta, Nobuo

    2017-03-23

    Eradication of schistosomiasis japonica in Yamanashi Prefecture was officially declared in 1996, and all surveillance and health campaign were finished by the end of 2001. Schistosomiasis control had been carried out by strong collaboration among local Government, local people and academia, thought which knowledge and experiences of the disease control were accumulated among the local people. It is 20(th) anniversary of the disease eradication in Yamanashi. We planned to analyze the current situation whether the local people still keep the knowledge of schistosomiasis or not. There was no more knowledge kept in the middle school students, to whom the local Government did not educate about schistosomiasis. Among adult individuals, elderly people who have experienced endemic condition still know about it at almost comparable level as in the past. However, younger people who learned it in the primary school but no experience of the disease transmission started losing the knowledge. Those situations of the adult local people were compared with the veterinarian group. It was confirmed that the veterinarian group had correct and proper knowledge of schistosomiasis japonica not only in elderly groups, but also in younger age group. Considering that methods for control and prevention of infectious diseases are common to some extent, their knowledge and experiences would be applicable for other infectious diseases in future. Therefore, the knowledge would be worth keeping in the local people. Taken together, individuals with specialty, such as veterinarians, are expected to play roles in public health for promotion of health and welfare.

  16. Aspartate transaminase to platelet ratio index in hepatitis C virus and Schistosomiasis coinfection

    PubMed Central

    Derbala, Moutaz; Elbadri, Mohammed Elshiekh; Amer, Aliaa Mohamed; AlKaabi, Saad; Sultan, Khaleel Hassan; Kamel, Yasser Medhat; Elsayed, Eman Hassan Satti; Avades, Tony Yervant; Chandra, Prem; Shebl, Fatma M

    2015-01-01

    AIM: To assess the diagnostic accuracy, of aminotransferase-to-platelet ratio index (APRI) alone and with antischistosomal antibody (Ab) in patients with hepatitis C virus (HCV) and schistosomiasis coinfection. METHODS: This retrospective study included medical records of three hundred and eighty three Egyptian men patients who had undergone percutaneous liver biopsy between January 2006 to April 2014 in tertiary care hospital in Qatar for diagnosis or monitoring purpose were selected. Data of patients > 18 years of age were included in the study. The values of HCV RNA titer and antischistosomal antibody titer were also taken into consideration. Patients were excluded from the study if they had any other concomitant chronic liver disease, including; history of previous antiviral or interferon therapy, immunosuppressive, therapy, chronic hepatitis B infection, human immunodeficiency virus co-infection, autoimmune hepatitis, decompensated liver disease, hepatocellular carcinoma, prior liver transplantation, and if no data about the liver biopsy present. RESULTS: Median age of patients was 46 years. About 7.1% had no fibrosis, whereas 30.4%, 37.5%, 20.4%, and 4.6% had fibrosis of stage I, II, III, and IV respectively. In bivariate analysis, APRI score, levels of AST, platelet count and age of patient showed statistically significant association with liver fibrosis (P < 0.0001); whereas antischistosomal antibody titer (P = 0.52) and HCV RNA titer (P = 0.79) failed to show a significant association. The respective AUC values for no fibrosis, significant fibrosis, severe fibrosis and cirrhosis of APRI score were 63%, 73.2%, 81.1% and 88.9% respectively. This showed good sensitivity and specificity of APRI alone for grading of liver fibrosis. But the inclusion of anti-Schistosoma antibody did not improve the prediction of fibrosis stage. CONCLUSION: The study results suggest that noninvasive biochemical markers like APRI are sensitive and specific in diagnosing the

  17. Independent Study in Iowa.

    ERIC Educational Resources Information Center

    Idaho Univ., Moscow.

    This guide to independent study in Idaho begins with introductory information on the following aspects of independent study: the Independent Study in Idaho consortium, student eligibility, special needs, starting dates, registration, costs, textbooks and instructional materials, e-mail and faxing, refunds, choosing a course, time limits, speed…

  18. New opportunities seen for independents

    SciTech Connect

    Adams, G.A. )

    1990-10-22

    The collapse of gas and oil prices in the mid-1980s significantly reduced the number of independent exploration companies. At the same time, a fundamental shift occurred among major oil companies as they allocated their exploration budgets toward international operations and made major production purchases. Several large independents also embraced a philosophy of budget supplementation through joint venture partnership arrangements. This has created a unique and unusual window of opportunity for the smaller independents (defined for this article as exploration and production companies with a market value of less than $1 billion) to access the extensive and high quality domestic prospect inventories of the major and large independent oil and gas companies and to participate in the search for large reserve targets on attractive joint venture terms. Participation in these types of joint ventures, in conjunction with internally generated plays selected through the use of today's advanced technology (computer-enhanced, high-resolution seismic; horizontal drilling; etc.) and increasing process for oil and natural gas, presents the domestic exploration-oriented independent with an attractive money-making opportunity for the 1990s.

  19. An Approach to Keeping Independent Colleges Independent.

    ERIC Educational Resources Information Center

    Northwest Area Foundation, St. Paul, Minn.

    As a result of the financial difficulties faced by independent colleges in the northwestern United States, the Northwest Area Foundation in 1972 surveyed the administrations of 80 private colleges to get a profile of the colleges, a list of their current problems, and some indication of how the problems might be approached. The three top problems…

  20. The snail hosts of schistosomiasis: some evolutionary and ecological perspectives in relation to control.

    PubMed

    Thomas, J D

    1995-01-01

    Despite opportunities for radiation provided by spatio-temporal isolation, the basic morphological plan of pulmonate snails has remained conservative. In consequence of the resulting dearth of morphological characters and their plasticity, there is a case for using biochemical characters such as exogenous chemicals released by the snails (e.g. amino acids) and their chemoreception niche as taxonomic aids to classify snails of medical importance. As these same chemicals are used by snails to distinguish conspecifics they could also be used as "environmental antibodies" in controlled release formulations (CRF's) designed to remove target snails in a specific, cost-effective and ecologically acceptable manner. The snails, surface-living bacteria, algae and macrophytic plants are considered as co-evolved, interactive modular systems with strong mutualistic elements. Recently, anthropogenic perturbations such as deforestation, and damming of flowing waters, have benefited these modules whereas others such as river canalization, acid deposition, accumulation of pesticide residues and eutrophication have harmed them. Research is needed to elucidate the factors which limit the growth of snails in primitive habitats, uninfluenced by man, as well as in those subject to harmful anthropogenic factors. The understanding thus gained could be applied to develop cost-effective primary health care strategies to reduce or prevent transmission of schistosomiasis and other water related diseases.

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

    PubMed

    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.

  2. Magnetic Resonance Spectroscopy for Evaluating Portal-Systemic Encephalopathy in Patients with Chronic Hepatic Schistosomiasis Japonicum

    PubMed Central

    Li, Ying; Mei, Lihong; Qiang, Jinwei; Ju, Shuai; Zhao, Shuhui

    2016-01-01

    Portal-systemic encephalopathy (PSE) is classified as type B hepatic encephalopathy. Portal-systemic shunting rather than liver dysfunction is the main cause of PSE in chronic hepatic schistosomiasis japonicum (HSJ) patients. Owing to lack of detectable evidence of intrinsic liver disease, chronic HSJ patients with PSE are frequently clinically undetected or misdiagnosed, especially chronic HSJ patients with covert PSE (subclinical encephalopathy). In this study, we investigated whether magnetic resonance spectroscopy (MRS) could be a useful tool for diagnosing PSE in chronic HSJ patients. Magnetic resonance (MR) T1-weighted imaging, diffusion-weighted imaging, and MRS were performed in 41 chronic HSJ patients with suspected PSE and in 21 age-matched controls. The T1 signal intensity index (T1SI) and apparent diffusion coefficient (ADC) value were obtained in the Globus pallidus. Liver function was also investigated via serum ammonia and liver function tests. Higher T1SI and ADC values, increased lactate and glutamine levels, and decreased myo-inositol were found in the bilateral Globus pallidus in chronic HSJ patients with PSE. No significantly abnormal serum ammonia or liver function tests were observed in chronic HSJ patients with PSE. On the basis of these findings, we propose a diagnostic procedure for PSE in chronic HSJ patients. This study reveals that MRS can be useful for diagnosing PSE in chronic HSJ patients. PMID:27977668

  3. When history was made in Khartoum Civil Hospital: First introduction of chemotherapy for schistosomiasis

    PubMed Central

    2015-01-01

    John Brian Christopherson (1868–1955) was one of the first doctors to be recruited to serve in the Sudan under the British colonial rule. During his work in Sudan (1902–1919) he was key in establishing the civilian medical services in Sudan, including establishing Khartoum Civil Hospital (opened in 1909). The present article focuses on the work of Dr Christopherson in Khartoum Civil Hospital in which he introduced tartar emetic for the first time for the treatment of schistosomiasis. To validate this treatment, Christopherson conducted a series of clinical trials and published his findings in leading medical journals. He had to respond to priority claims over this discovery and to deal with skepticism about the safety of this new treatment. The publications of Christopherson covered not only the therapeutic efficacy of the drug but also discussed the epidemiology of the disease, the possible role of mass chemotherapy and also envisioned chemotherapy in school-age children as a possible strategy for future elimination of the disease. PMID:27493441

  4. Diagnosis of schistosomiasis japonica with interfacial co-assembly-based multi-channel electrochemical immunosensor arrays.

    PubMed

    Deng, Wangping; Xu, Bin; Hu, Haiyan; Li, Jianyong; Hu, Wei; Song, Shiping; Feng, Zheng; Fan, Chunhai

    2013-01-01

    Schistosomiasis control remains to be an important and challenging task in the world. However, lack of quick, simple, sensitive and specific sero-diagnostic test is still a hurdle in the control practice. The commonly employed enzyme-linked immuno-sorbent assay (ELISA) relies on the native soluble egg antigen (SEA) that is limited in supply. Here we developed an electrochemical immunosensor array (ECISA) assay with an interfacial co-assembly strategy. A recombinant Schistosoma japonicum (Sj) calcium-binding protein (SjE16) was used as a principal antigen, while the SEA as a minor, co-assembling agent, with a ratio of 8:1 (SjE16: SEA, Sj16EA), which was co-immobilized on a disposable 16-channel screen-printed carbon electrode array. A portable electrochemical detector was employed to detect antibodies in serum samples. The sensitivity of ECISA reached 100% with minimal cross-reactions. Therefore, we have demonstrated that this rapid, sensitive and specific ECISA technique has the potential to perform large-scale on-site screening of Sj infection.

  5. Factors impacting on progress towards elimination of transmission of schistosomiasis japonica in China

    PubMed Central

    2012-01-01

    Over the past decades China has made a great stride in controlling schistosomiasis, eliminating transmission of Schistosoma japonicum in 5 provinces and remarkably reducing transmission intensities in the rest of the seven endemic provinces. Recently, an integrated control strategy, which focuses on interventions on humans and bovines, has been implemented throughout endemic areas in China. This strategy assumes that a reduction in transmission of S. japonicum from humans and bovines to the intermediate Oncomelania snail host would eventually block the transmission of this parasite, and has yielded effective results in some endemic areas. Yet the transmission of S. japonicum is relatively complicated – in addition to humans and bovines, more than 40 species of mammalians can serve as potential zoonotic reservoirs. Here, we caution that some factors – potential roles of other mammalian reservoirs and human movement in sustaining the transmission, low sensitivity/specificity of current diagnostic tools for infections, praziquantel treatment failures, changes in environmental and socio-economic factors such as flooding in key endemic areas - may pose great obstacles towards transmission interruption of the parasite. Assessing potential roles of these factors in the transmission and implications for current control strategies aiming at transmission interruption is needed. PMID:23206326

  6. Barbatic Acid Offers a New Possibility for Control of Biomphalaria Glabrata and Schistosomiasis.

    PubMed

    Martins, Mônica Cristina Barroso; Silva, Monique Costa; Silva, Hianna Arely Milca Fagundes; Silva, Luanna Ribeiro Santos; Albuquerque, Mônica Camelo Pessoa de Azevedo; Aires, André Lima; Falcão, Emerson Peter da Silva; Pereira, Eugênia C; de Melo, Ana Maria Mendonça Albuquerque; da Silva, Nicácio Henrique

    2017-03-31

    This study evaluated the biological activity of an ether extract and barbatic acid (BAR) from Cladia aggregata on embryos and adult mollusks of Biomphalaria glabrata, cercariae of Schistosoma mansoni and the microcrustacean Artemia salina. The ether extract and BAR were obtained by successive extractions with diethyl ether. The obtained extracts were analyzed using thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC), proton nuclear magnetic resonance (¹H-NMR) and infrared (IR) spectroscopy. The results demonstrated that the ether extract exerted embryotoxic effects at 50 and 100 µg/mL and molluscicidal effects at 20 and 25 µg/mL. BAR exhibited no embryotoxicity, and its molluscicidal concentration was equal to that of the ether extract. However, after 60 min of exposure, 1 µg/mL BAR presented cercaricidal activity against the parasite S. mansoni at the second larval stage. Neither substance induced toxicity against A. salina. These results indicate the potential molluscicidal activities of the ether extract and BAR against B. glabrata and S. mansoni cercariae. In addition to these effects, there was a lack of toxicity against the aquatic environment and no damage to the biota, indicating the potential of these products for large-scale control and/or eradication of schistosomiasis.

  7. [Evaluation of 10 years of research on S. mansoni schistosomiasis A in the French West Indies].

    PubMed

    Combes, C; Golvan, Y; Salvat, B

    1982-03-01

    From 1971 until 1982, we studied the ecological factors which stead fast a perennial schistosomiasis in Guadeloupe on an exhaustive mode. More recently, we start a similar investigation in Martinique. In Guadeloupe the single vector of Schistosoma mansoni is the snail Biomphalaria glabrata which is an ubiquist species. But the transmission to man is restricted to the "canal-sewers" where faeces are dropped and not in the rivers of Basse-Terre or the ponds of Grande-Terre. Moreover, the infection is possible only during the hottest hours of the day, when the cercariae get out of the snail. We built a "cercariometer" with which we are able to know the number of cercariae per litre in a given place at every hour of day and night. The black rat (and not the grey rat!) seems, alone, able to maintain the life-cycle of the parasite, at least in the mangrove forests. It is now possible to "clone" S. mansoni by sporocysts transplantation in non-infected snails. The biological control of B. glabrata populations is possible by sterilizating Trematodes such as Ribeiroia guadeloupensis. A new built irrigation reservoir in Grande-Terre give a chance of spread for the endemy in an area which was, till now, unharmed.

  8. Environmental effects on parasitic disease transmission exemplified by schistosomiasis in western China

    PubMed Central

    Liang, Song; Seto, Edmund Y. W.; Remais, Justin V.; Zhong, Bo; Yang, Changhong; Hubbard, Alan; Davis, George M.; Gu, Xueguang; Qiu, Dongchuan; Spear, Robert C.

    2007-01-01

    Environmental effects on the transmission of many parasitic diseases are well recognized, but the role of specific factors like climate and agricultural practices in modulating transmission is seldom characterized quantitatively. Based on studies of Schistosoma japonicum transmission in irrigated agricultural environments in western China, a mathematical model was used to quantify environmental impacts on transmission intensity. The model was calibrated by using field data from intervention studies in three villages and simulated to predict the effects of alternative control options. Both the results of these interventions and earlier epidemiological findings confirm the central role of environmental factors, particularly those relating to snail habitat and agricultural and sanitation practices. Moreover, the findings indicate the inadequacy of current niclosamide-praziquantel strategies alone to achieve sustainable interruption of transmission in some endemic areas. More generally, the analysis suggests a village-specific index of transmission potential and how this potential is modulated by time-varying factors, including climatological variables, seasonal water-contact patterns, and irrigation practices. These time-variable factors, a village's internal potential, and its connectedness to its neighbors provide a framework for evaluating the likelihood of sustained schistosomiasis transmission and suggest an approach to quantifying the role of environmental factors for other parasitic diseases. PMID:17438266

  9. Magnetic Resonance Spectroscopy for Evaluating Portal-Systemic Encephalopathy in Patients with Chronic Hepatic Schistosomiasis Japonicum.

    PubMed

    Li, Ying; Mei, Lihong; Qiang, Jinwei; Ju, Shuai; Zhao, Shuhui

    2016-12-01

    Portal-systemic encephalopathy (PSE) is classified as type B hepatic encephalopathy. Portal-systemic shunting rather than liver dysfunction is the main cause of PSE in chronic hepatic schistosomiasis japonicum (HSJ) patients. Owing to lack of detectable evidence of intrinsic liver disease, chronic HSJ patients with PSE are frequently clinically undetected or misdiagnosed, especially chronic HSJ patients with covert PSE (subclinical encephalopathy). In this study, we investigated whether magnetic resonance spectroscopy (MRS) could be a useful tool for diagnosing PSE in chronic HSJ patients. Magnetic resonance (MR) T1-weighted imaging, diffusion-weighted imaging, and MRS were performed in 41 chronic HSJ patients with suspected PSE and in 21 age-matched controls. The T1 signal intensity index (T1SI) and apparent diffusion coefficient (ADC) value were obtained in the Globus pallidus. Liver function was also investigated via serum ammonia and liver function tests. Higher T1SI and ADC values, increased lactate and glutamine levels, and decreased myo-inositol were found in the bilateral Globus pallidus in chronic HSJ patients with PSE. No significantly abnormal serum ammonia or liver function tests were observed in chronic HSJ patients with PSE. On the basis of these findings, we propose a diagnostic procedure for PSE in chronic HSJ patients. This study reveals that MRS can be useful for diagnosing PSE in chronic HSJ patients.

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

    SciTech Connect

    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. Diagnosis of schistosomiasis japonica with interfacial co-assembly-based multi-channel electrochemical immunosensor arrays

    NASA Astrophysics Data System (ADS)

    Deng, Wangping; Xu, Bin; Hu, Haiyan; Li, Jianyong; Hu, Wei; Song, Shiping; Feng, Zheng; Fan, Chunhai

    2013-05-01

    Schistosomiasis control remains to be an important and challenging task in the world. However, lack of quick, simple, sensitive and specific sero-diagnostic test is still a hurdle in the control practice. The commonly employed enzyme-linked immuno-sorbent assay (ELISA) relies on the native soluble egg antigen (SEA) that is limited in supply. Here we developed an electrochemical immunosensor array (ECISA) assay with an interfacial co-assembly strategy. A recombinant Schistosoma japonicum (Sj) calcium-binding protein (SjE16) was used as a principal antigen, while the SEA as a minor, co-assembling agent, with a ratio of 8:1 (SjE16: SEA, Sj16EA), which was co-immobilized on a disposable 16-channel screen-printed carbon electrode array. A portable electrochemical detector was employed to detect antibodies in serum samples. The sensitivity of ECISA reached 100% with minimal cross-reactions. Therefore, we have demonstrated that this rapid, sensitive and specific ECISA technique has the potential to perform large-scale on-site screening of Sj infection.

  12. Schistosomiasis in a low prevalence area: incomplete urbanization increasing risk of infection in Paracambi, RJ, Brazil.

    PubMed

    Soares, M S; Barreto, M G; da Silva, C L; Pereira, J B; Moza, P G; Rey, L; Calçado, M S; Lustoza, A; Maspero, R

    1995-01-01

    The risk of schistosomiasis infection and heavy infection in the locality of Sabugo was evaluated in relation to housing in areas with different urbanization development and to residential supply with snail-infested water. Critical sanitary conditions were found in areas of incomplete urbanization, where healthy water supply sources were scarce, and draining of sewage, without previous treatment, was made directly to the water-bodies used for domestic and leisure activities, despite being Biomphalaria tenagophila snail breeding-places. Stool examinations (Kato-Katz and Lutz methods) showed prevalence of 2.9% mean intensity of 79 eggs per gram of stool and 47% of positive cases presenting intense infection. The use of snail-contaminated water for domestic purposes was considered a risk factor for infection. It is concluded that incomplete urbanization would facilitate transmission, probably enhancing the intensity of infection and that a low prevalence could hide a highly focal transmission. The relevance of these facts upon the efficiency of epidemiologic study methods and disease control planning are then discussed.

  13. [Oltipraz as brief treatment of schistosomiasis (comparison with niridazole) (author's transl)].

    PubMed

    Pieron, R; Lesobre, B; Mafart, Y; Lancastre, F

    1980-01-01

    161 patients affected by schistosomiasis due in most cases to S. haematobium, and less frequently to S. mansoni, received one day treatment with 4,5 g a day of oltipraz in a first group and, later on, 3 g a day in another group. A control after one year was possible for patients having received 4,5 g one day dosis. Urin control, rectal mucosa biopsy (R.M.B.) and indirect immunofluorescence test (I.I.F.) were performed in patients who did not return to infested areas during that period of time; in almost all cases, the urin control was negative; in 52 p. 100 of the cases the R.M.B. shown no live egg and I.I.F. test was significantly decreased with individual variations. -- These results are compared to those of a previous and similar study on the effects of niridazole. -- Side-effects, mostly digestive or nervous, are frequent with a 4,5 g dose and less frequent with 3 g. They rarely compel to discard the treatment and they never persist after the morning following the treatment is stopped. There is no electrocardiographic change. -- Doses below 3 g in one-day intake are presently studied in order to fix the minimal acting dosis.

  14. Studies on the molluscicidal activity of Agave angustifolia and Pittosporum tobira on schistosomiasis transmitting snails.

    PubMed

    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.

  15. Repeated praziquantel treatments remodel the genetic and spatial landscape of schistosomiasis risk and transmission.

    PubMed

    Barbosa, Lúcio M; Reis, Eliana A; Dos Santos, Cláudio R A; Costa, Jackson M; Carmo, Theomira M; Aminu, Peace T; Pitanga, Thassila N; Ponce-Terashima, Rafael; Blank, Walter A; Silva, Luciano K; Reis, Mitermayer G; Blanton, Ronald E

    2016-05-01

    Repeated treatments with praziquantel reduce schistosomiasis prevalence and morbidity, but transmission persists and populations often recover within a few years. To identify factors associated with persistence, we surveyed and treated all identified Schistosoma mansoni infections in two rural Brazilian communities (Jenipapo and Volta do Rio) in 2009, 2012 and 2013. Eggs were collected from all infected individuals and genotyped with 11 microsatellite markers to evaluate parasite differentiation and diversity. After successive rounds of community-wide treatment, prevalence decreased from 45% to 24% then 16%. Intensity of infection decreased by 57% over this period, and the number of eggs transmitted to the environment decreased by 92%. During all time periods the majority of eggs were excreted by those >15years of age. The incidence was 23% in 2012 and 15% in 2013, consistent with a decrease in transmission. There was little immigration or gene flow over a distance of 6km. On reinfection, infrapopulations were moderately differentiated indicating that pretreatment multilocus genotypes were not fully reacquired. The effective population size responded to census population decline more rapidly than differentiation. Reinfection was concentrated in the downstream portion of Jenipapo, consistent with the observed increased human fecal contamination. At this scale and in this area S. mansoni infections exist on a fragmented landscape with a highly focal pattern of transmission that may facilitate future elimination.

  16. Risk Transmission Indicator of Schistosomiasis Japonicum Considering Human Activities in Lake and Marshland Regions- A Case Study of Poyang Lake, Jiangxi Province, P.R. China

    NASA Astrophysics Data System (ADS)

    Marie, Tiphanie; Yesou, Herve; Huber, Claire; De Fraipont, Paul; Uribe, Carlos; Lacaux, Jean-Pierre; Lafaye, Murielle; Lai, Xijun; Desnos, Yves-Louis

    2013-01-01

    This paper present the method used to determine the areas where schistosomiasis transmission is the higher. A primary work was necessary to this study: identification of potential presence of schistosomiasis japonicum’s vector in Poyang lakeshore area (Jiangxi Province, P.R. China). Results obtained from its first work were crossing with the most risky human activities and with villages to elaborate a level of transmission risk. The first parameter determined concern fishing, which was identified like the most risky activity for schistosomiasis transmission, and fish traps were digitalized using a very high resolution ALOS data. The second parameter is about the risky areas for buffalo grazing, and vector potential presence areas were crossed with village proximity to determine the most risky areas for human transmission. The third parameter built is a level of risk for each village digitalized around Poyang Lake, taking into account the proximity and level of potential presence of vector’s areas.

  17. The effect of a health communication campaign on compliance with mass drug administration for schistosomiasis control in western Kenya--the SCORE project.

    PubMed

    Omedo, Martin; Ogutu, Michael; Awiti, Alphonce; Musuva, Rosemary; Muchiri, Geoffrey; Montgomery, Susan P; Secor, W Evan; Mwinzi, Pauline

    2014-11-01

    Compliance with mass drug administration (MDA) can be affected by rumors and mistrust about the drug. Communication campaigns are an effective way to influence attitudes and health behaviors in diverse public health contexts, but there is very little documentation about experiences using health communications in schistosomiasis control programs. A qualitative study was conducted with community health workers (CHWs) as informants to explore the effect of a health communication campaign on their experiences during subsequent praziquantel MDA for schistosomiasis. Discussions were audio-recorded, transcribed verbatim, translated into English where applicable, and analyzed thematically using ATLAS.ti software. According to the CHWs, exposure to mass media messages improved awareness of the MDA, which in turn, led to better treatment compliance. Our findings suggest that communication campaigns influence health behaviors and create awareness of schistosomiasis control interventions, which may ultimately improve praziquantel MDA.

  18. Chemotherapeutic Studies on Schistosomiasis and Clinical, Epidemiological and Immunological Studies on Malaria in Amazonas, Brazil, along the Ituxi River. Report Number VII.

    DTIC Science & Technology

    1980-10-01

    AD-AlI 539 BRASILIA UNIV ( BRAZIL ) F/S 6/5 CHEMOTHERAPEUTIC STUDIES ON SCHISTOSOMIASIS AND CLINICAL. EPIDE-ETCIU) OCT 80 A R PRATA, W A REID, D R...Chemotherapeutic Studies on Schistosomiasis and Clinical, Epidemio- logical and Immunological Studies on Malaria in Amazonas,- Brazil ,.Along the Ituxi River...79-G-9464 University of Brasilia 70.910 Brasilia, D.F., Brazil And ’U.S. Army Medical Research Unit (WRAIR)/Brasilia APO Miami 34030 DTIC : I ELECTE

  19. Distribution and abundance of schistosomiasis and fascioliasis host snails along the Mara River in Kenya and Tanzania.

    PubMed

    Dida, Gabriel O; Gelder, Frank B; Anyona, Douglas N; Matano, Ally-Said; Abuom, Paul O; Adoka, Samson O; Ouma, Collins; Kanangire, Canisius K; Owuor, Phillip O; Ofulla, Ayub V O

    2014-01-01

    We purposively selected 39 sampling sites along the Mara River and its two perennial tributaries of Amala and Nyangores and sampled snails. In addition, water physicochemical parameters (temperature, turbidity, dissolved oxygen, conductivity, alkalinity, salinity and pH) were taken to establish their influence on the snail abundance and habitat preference. Out of the 39 sites sampled, 10 (25.6%) had snails. The snail species encountered included Biomphalaria pfeifferi Krauss - the intermediate host of Schistosoma mansoni Sambon, Bulinus africanus - the intermediate host of Schistosoma haematobium, and Lymnaea natalensis Krauss - the intermediate host of both Fasciola gigantica and F. hepatica Cobbold. Ceratophallus spp., a non-vector snail was also encountered. Most (61.0%) of the snails were encountered in streamside pools. Schistosomiasis-transmitting host snails, B. pfeifferi and B. africanus, were fewer than fascioliasis-transmitting Lymnaea species. All the four different snail species were found to be attached to different aquatic weeds, with B. pfeifferi accounting for over half (61.1%) of the snails attached to the sedge, followed by B. africanus and Lymnaea spp., accounting for 22.2 and 16.7%, respectively. Ceratophallus spp. were non-existent in sedge. The results from this preliminary study show that snails intermediate hosts of schistosomiasis and fascioliasis exists in different habitats, in few areas along the Mara River, though their densities are still low to have any noticeable impacts on disease transmission in case they are infected. The mere presence of the vector snails in these focal regions calls for their immediate control and institution of proper regulations, management, and education among the locals that can help curtail the spread of the snails and also schistosomiasis and fascioliasis within the Mara River basin.

  20. Potential Cost-Effectiveness of Schistosomiasis Treatment for Reducing HIV Transmission in Africa – The Case of Zimbabwean Women

    PubMed Central

    Ndeffo Mbah, Martial L.; Poolman, Eric M.; Atkins, Katherine E.; Orenstein, Evan W.; Meyers, Lauren Ancel; Townsend, Jeffrey P.; Galvani, Alison P.

    2013-01-01

    Background Epidemiological data from Zimbabwe suggests that genital infection with Schistosoma haematobium may increase the risk of HIV infection in young women. Therefore, the treatment of Schistosoma haematobium with praziquantel could be a potential strategy for reducing HIV infection. Here we assess the potential cost-effectiveness of praziquantel as a novel intervention strategy against HIV infection. Methods We developed a mathematical model of female genital schistosomiasis (FGS) and HIV infections in Zimbabwe that we fitted to cross-sectional data of FGS and HIV prevalence of 1999. We validated our epidemic projections using antenatal clinic data on HIV prevalence. We simulated annual praziquantel administration to school-age children. We then used these model predictions to perform a cost-effectiveness analysis of annual administration of praziquantel as a potential measure to reduce the burden of HIV in sub-Saharan Africa. Findings We showed that for a variation of efficacy between 30–70% of mass praziquantel administration for reducing the enhanced risk of HIV transmission per sexual act due to FGS, annual administration of praziquantel to school-age children in Zimbabwe could result in net savings of US$16–101 million compared with no mass treatment of schistosomiasis over a ten-year period. For a variation in efficacy between 30–70% of mass praziquantel administration for reducing the acquisition of FGS, annual administration of praziquantel to school-age children could result in net savings of US$36−92 million over a ten-year period. Conclusions In addition to reducing schistosomiasis burden, mass praziquantel administration may be a highly cost-effective way of reducing HIV infections in sub-Saharan Africa. Program costs per case of HIV averted are similar to, and under some conditions much better than, other interventions that are currently implemented in Africa to reduce HIV transmission. As a cost-saving strategy, mass praziquantel

  1. The Effect of Simulating Different Intermediate Host Snail Species on the Link between Water Temperature and Schistosomiasis Risk

    PubMed Central

    McCreesh, Nicky; Booth, Mark

    2014-01-01

    Introduction A number of studies have attempted to predict the effects of climate change on schistosomiasis risk. The importance of considering different species of intermediate host snails separately has never previously been explored. Methods An agent-based model of water temperature and Biomphalaria pfeifferi population dynamics and Schistosoma mansoni transmission was parameterised to two additional species of snail: B. glabrata and B. alexandrina. Results Simulated B. alexandrina populations had lower minimum and maximum temperatures for survival than B. pfeifferi populations (12.5–29.5°C vs. 14.0–31.5°C). B. glabrata populations survived over a smaller range of temperatures than either B. pfeifferi or B. alexandrina (17.0°C–29.5°C). Infection risk peaked at 16.5°C, 25.0°C and 19.0°C respectively when B. pfeifferi, B. glabrata and B. alexandrina were simulated. For all species, infection risk increased sharply once a minimum temperature was reached. Conclusions The results from all three species suggest that infection risk may increase dramatically with small increases in temperature in areas at or near the currents limits of schistosome transmission. The effect of small increases in temperature in areas where schistosomiasis is currently found will depend both on current temperatures and on the species of snail acting as intermediate host(s) in the area. In most areas where B. pfeifferi is the host, infection risk is likely to decrease. In cooler areas where B. glabrata is the host, infection risk may increase slightly. In cooler areas where B. alexandrina is the host, infection risk may more than double with only 2°C increase in temperature. Our results show that it is crucial to consider the species of intermediate host when attempting to predict the effects of climate change on schistosomiasis. PMID:24988377

  2. Chemotherapeutic Studies on Schistosomiasis and Clinical Epidemiological and Immunological Studies on Malaria in Amazonas, Brazil, Along the Ituxi River.

    DTIC Science & Technology

    1979-10-01

    AD-A098 308 BRASILIA UNIV ( BRAZIL ) F/ 6 /5 C H MOTHERAPEUTI C STUDIES ON SCHISTOSOMIASIS AND CLINICAL EPIOEM--ETCC OCT 79 A R PRATA, W A REID. D R...AMAZONAS, BRAZIL , ALONG THE ITUXI RIVER 0 FINAL REPORT Aluizio R. Prata X Willis A. Reid, JR. MDonald R. Roberts 0 K. Mills McNeill October 1979...T IC Brasilia, Brazil S ELEAPR2CTE9 981 r B APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED The findings in this report are not to be construed as

  3. Integrated community-directed treatment for the control of onchocerciasis, schistosomiasis and intestinal helminths infections in Uganda: advantages and disadvantages.

    PubMed

    Ndyomugyenyi, Richard; Kabatereine, Narcis

    2003-11-01

    Onchocerciasis is co-endemic with schistosomiasis and intestinal helminths infections, which are all diseases of the rural and the poorest communities in Africa. Community-directed treatment (ComDT) for the control of onchocerciasis is the only functional health approach in most of these communities and the strategy has proven to be effective for onchocerciasis control. This study was conducted to assess the feasibility of integrating ComDT with ivermectin for the control of onchocerciasis, and with praziquantel (PZQ) and mebendazole (MBD) for the control of schistosomiasis and intestinal helminths infections in children aged 5-14 years, and to assess advantages and disadvantages of the integrated ComDT over the routine ComDT and the school-based treatment approach. Integrated ComDT achieved higher treatment coverage (85%) for PZQ and MBD than the school-based treatment approach (79%) among children aged 5-14 years (P = 0.03). There were more reported adverse reactions after treatment with a combination of PZQ and MBD in the school-based treatment approach (33%) than for the combination of ivermectin and MBD on day 1 and PZQ on day 2 in the integrated ComDT (18%). However, all adverse reactions were mild (headache, nausea/vomiting and abdominal pain). The integrated ComDT also achieved higher ivermectin treatment coverage for all ages (81.3%) than routine ComDT (77.2%) (P = 0.0003). To achieve even better coverage for PZQ and MBD among the targeted high risk groups, integrated ComDT should treat all age groups in areas where the prevalence of schistosomiasis and intestinal helminths infections is >50%. This would minimize the shortage of the drugs targeted to treat the high risk groups, as the non-targeted groups, will inevitably demand and receive the treatment from the distributors. The results of this study show that PZQ and MBD treatment for the control of schistosomiasis and intestinal helminths, respectively, can be integrated with ivermectin treatment for

  4. Effect of National Schistosomiasis Control Programme on Taenia solium taeniosis and porcine cysticercosis in rural communities of Tanzania.

    PubMed

    Braae, Uffe Christian; Magnussen, Pascal; Harrison, Wendy; Ndawi, Benedict; Lekule, Faustin; Johansen, Maria Vang

    2016-09-01

    Taenia solium is found throughout sub-Saharan Africa and co-endemic with schistosomiasis in many regions. Taenia solium leads to taeniosis and neurocysticercosis - the leading cause of preventable epilepsy globally. This study aimed to assess the effects of the National Schistosomiasis Control Programme on prevalence of taeniosis and porcine cysticercosis over a four year period in Tanzania. School-based mass drug administration (MDA) of praziquantel was carried out based on schistosomiasis endemicity. Four human and five porcine cross-sectional surveys were carried out from 2012 to 2015 in Mbozi and Mbeya district in Tanzania. Three rounds of school-based MDA of praziquantel were delivered in Mbozi and two in Mbeya. The prevalence of taeniosis and porcine cysticercosis was estimated annually. Stool samples were collected from humans and prevalence of taeniosis estimated by copro-Ag-ELISA. Blood samples from pigs were collected to estimate cysticercosis prevalence by Ag-ELISA. "Track-and-treat" of taeniosis cases was carried out after each survey. In total 12082 stool samples and 4579 porcine serum samples were collected. Significantly fewer children (≤ 15) from Mbozi were infected throughout the study than children from Mbeya who showed a significant decrease in copro-Ag prevalence after the first treatment only. During the final survey in Mbozi the prevalence of taeniosis in adults (1.8%) was significantly lower (p = 0.031, OR 0.40, CI: 0.17-0.89), compared to baseline (4.1%). The prevalence of porcine cysticercosis (8%) had also dropped significantly (p = 0.002, OR 0.49, CI: 0.32-0.76) in this district compared to baseline (13%), whereas no significant difference was seen in Mbeya compared to baseline. The study suggests that three rounds of MDA targeting schistosomiasis in school-aged children combined with 'track-and-treat' contributed to a reduction in prevalence of T. solium in this population, and also had a spillover effect on adults in treated

  5. [Sociodemographic and behavioral factors related to schistosomiasis in a rural village of the sugar cane belt in Pernambuco State, Brazil

    PubMed

    Moza; Pieri; Barbosa; Rey

    1998-04-30

    Failure of intensive chemotherapy to control schistosomiasis in a highly endemic area of Northeast Brazil led to the hypothesis that sociodemographic and/or behavioral variables could be involved in the persistent transmission. A univariate analysis of such variables in relation to infection by Schistosoma mansoni showed that water contact patterns for recreation and personal hygiene are important risk factors in the area. However, sociodemographic variables were not related to infection, probably because the local population lives under evenly precarious socioeconomic and sanitary conditions. We thus recommend that chemotherapy be combined with other measures like snail control, health education, and improved sanitation and water supply.

  6. American Independence. Fifth Grade.

    ERIC Educational Resources Information Center

    Crosby, Annette

    This fifth grade teaching unit covers early conflicts between the American colonies and Britain, battles of the American Revolutionary War, and the Declaration of Independence. Knowledge goals address the pre-revolutionary acts enforced by the British, the concepts of conflict and independence, and the major events and significant people from the…

  7. Independence of Internal Auditors.

    ERIC Educational Resources Information Center

    Montondon, Lucille; Meixner, Wilda F.

    1993-01-01

    A survey of 288 college and university auditors investigated patterns in their appointment, reporting, and supervisory practices as indicators of independence and objectivity. Results indicate a weakness in the positioning of internal auditing within institutions, possibly compromising auditor independence. Because the auditing function is…

  8. TENORM (Technologically Enhanced Naturally Occurring Radioactive Materials)

    MedlinePlus

    Jump to main content US EPA United States Environmental Protection Agency Search Search Radiation Protection Share Facebook Twitter Google+ Pinterest Contact Us Technologically Enhanced Naturally Occurring Radioactive ...

  9. The major parasite surface antigen associated with human resistance to schistosomiasis is a 37-kD glyceraldehyde-3P-dehydrogenase

    PubMed Central

    1989-01-01

    Schistosomiasis, due to Schistosoma mansoni, is a major health problem in many subtropical countries, and major efforts are being made to define a vaccine. In this regard, we have reported that sera from subjects with low susceptibility to infection by S. mansoni react with a major larval surface antigen (P-37), having an apparent molecular mass of 37 kD, against which sera of susceptible individuals show little reactivity. We have now cloned the cDNA for this antigen by screening a schistosome cDNA expression library with antibodies against the purified protein. The selected cDNAs encode a protein that is specifically identified by immune human sera containing antibodies against P-37, while sera exhibiting low or no reactivity toward P-37 fail to recognize the recombinant protein. The cloned cDNAs hybridize with a 1.2-kb RNA that is the transcript of a single copy gene. This RNA directs the synthesis of a 36.5-kD polypeptide that is precipitated by sera from the most resistant subjects. The amino acid sequence of the encoded polypeptide shows homology with the glycolytic enzyme Glyceraldehyde-3P-dehydrogenase (72.5% of positional identity with human Glyceraldehyde-3P-dehydrogenase). Antibodies against the recombinant protein identified P-37 on the larva. These findings, together with other reports, indicate that a number of conserved proteins may be major targets of host-protective immunity against S. mansoni. The hypothesis is discussed that genetic restriction of the immune response to these antigens may occur in heterogeneous human populations because of the limited number of T cell epitopes carried by these host-like proteins. Such genetic effects might allow parasite transmission through nonresponder (susceptible) individuals. This hypothesis and the protective properties of P-37 can now be tested using the recombinant protein and synthetic peptides derived from selected regions of the polypeptide chain. PMID:2584935

  10. Schistosomiasis Control Using Piplartine against Biomphalaria glabrata at Different Developmental Stages

    PubMed Central

    Rapado, Ludmila Nakamura; Pinheiro, Alessandro de Sá; Lopes, Priscila Orechio de Moraes Victor; Fokoue, Harold Hilarion; Scotti, Marcus Tullius; Marques, Joaquim Vogt; Ohlweiler, Fernanda Pires; Borrely, Sueli Ivone; Pereira, Carlos Alberto de Bragança; Kato, Massuo Jorge; Nakano, Eliana; Yamaguchi, Lydia Fumiko

    2013-01-01

    Background Schistosomiasis is one of the most significant diseases in tropical countries and affects almost 200 million people worldwide. The application of molluscicides to eliminate the parasite's intermediate host, Biomphalaria glabrata, from infected water supplies is one strategy currently being used to control the disease. Previous studies have shown a potent molluscicidal activity of crude extracts from Piper species, with extracts from Piper tuberculatum being among the most active. Methods and Findings The molluscicidal activity of P. tuberculatum was monitored on methanolic extracts from different organs (roots, leaves, fruit and stems). The compounds responsible for the molluscicidal activity were identified using 1H NMR and ESIMS data and multivariate analyses, including principal component analysis and partial least squares. These results indicated that the high molluscicidal activity displayed by root extracts (LC50 20.28 µg/ml) was due to the presence of piplartine, a well-known biologically-active amide. Piplartine was isolated from P. tuberculatum root extracts, and the molluscicidal activity of this compound on adults and embryos of B. glabrata was determined. The compound displayed potent activity against all developmental stages of B. glabrata. Next, the environmental toxicity of piplartine was evaluated using the microcrustacean Daphnia similis (LC50 7.32 µg/ml) and the fish Danio rerio (1.69 µg/ml). The toxicity to these organisms was less compared with the toxicity of niclosamide, a commercial molluscicide. Conclusions The development of a new, natural molluscicide is highly desirable, particularly because the commercially available molluscicide niclosamide is highly toxic to some organisms in the environment (LC50 0.25 µg/ml to D. similis and 0.12 µg/ml to D. rerio). Thus, piplartine is a potential candidate for a natural molluscicide that has been extracted from a tropical plant species and showed less toxic to environment. PMID

  11. Willingness-to-pay for schistosomiasis-related health outcomes in Kenya.

    PubMed

    Kirigia, J M; Sambo, L G; Kainyu, L H

    2000-01-01

    Cost-benefit analysis (CBA) provides a framework for identifying, quantifying, and valuing in monetary terms all the important costs and consequences to society of competing disease interventions. Thus, CBA requires that impacts of schistosomiasis interventions on beneficiaries'health be valued in monetary terms Economic theory requires the use of the willingness to pay (WTP) approach in valuation of changes in health as a result of intervention. It is the only approach which is consistent with the potential Pareto improvement principle, and hence, consistent with CBA. The present study developed a health outcome measure and tested its operational feasibility. Contingent valuation for certain return to normal health from various health states, and for remaining in one's current health state were elicited through direct interview of randomly selected rice farmers, teachers, and health personnel in Kenya. The WTP to avoid risk of advancing to the next more severe state, seemed to be higher than WTP for a return to normal health. Generally, there was a significant difference between the average WTP values of farmers, teachers and health personnel populations. The gender and occupation variable coefficients were positive and highly significant in all regressions. The coefficients of the other explanatory variables were generally not statistically significant, indicating that medical expenses, anxiety cost, loss of earnings, and loss of work time, implied in various health states descriptions did not have significant effect on respondents expressed WTP values. The latter finding shows that there is need for more research to identify the other (besides gender and occupation) determinants of expressed WTP values in Africa. This study has demonstrated that it is possible to elicit coherent WTP values from economically under-developed countries. Further empirical work is clearly needed to at least address the validity and reliability of the contingent valuation approach and

  12. Vaccination of bovines against Schistosomiasis japonica with highly irradiated schistosomula in China

    SciTech Connect

    Hsue, S.Y.; Xu, S.T.; He, Y.X.; Shi, F.H.; Shen, W.; Hsue, H.F.; Osborne, J.W.; Clarke, W.R.

    1984-09-01

    Vaccination of Chinese bovines (cattle and buffaloes) against Schistosomiasis japonica with 36 kR gamma-irradiated schistosomula was done for laboratory challenge and for field trials in China. Altogether, 61 bovines were used. All experimental animals were vaccinated 2-3 times with 10,000 irradiated schistosomula per time. For the laboratory challenge, all experimental and control cattle were challenged with 500 normal cercariae and each buffalo, with 2,000 cercariae. The laboratory-challenged bovines were killed after 54-57 days of challenge; the bovines for the field trial in the lightly endemic area, after 5 months in the field; and the bovines for the field trial in the heavily endemic area, after 58-63 days. When the animals were killed, the number of mature worms in the vaccinated (experimental) and non-vaccinated (control) animals was recorded and the percentage of worm reduction in each group was calculated. The first group, consisting of three vaccinated and three non-vaccinated cattle, was given a laboratory challenge; the worm reduction was 71.6%. The second group, consisting of two vaccinated and three non-vaccinated buffaloes, was also given a laboratory challenge; the worm reduction was 74.4%. The third group, consisting of seven vaccinated and eight non-vaccinated buffaloes, was utilized in a field trial in a lightly endemic area; the worm reduction was 75.6%. The fourth group, consisting of eight vaccinated and nine non-vaccinated cattle, and the fifth group, consisting of nine vaccinated and nine non-vaccinated buffaloes, were pastured in a heavily endemic area. The worm reduction was 65.1% in the fourth group and 75.7% in the fifth group.

  13. Rural tourism as risk factor for the transmission of schistosomiasis in Minas Gerais, Brazil.

    PubMed

    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.

  14. Localization of serotonin in the nervous system of Biomphalaria glabrata, an intermediate host for schistosomiasis.

    PubMed

    Delgado, Nadia; Vallejo, Deborah; Miller, Mark W

    2012-10-01

    The digenetic trematode Schistosoma mansoni that causes the form of schistosomiasis found in the Western Hemisphere requires the freshwater snail Biomphalaria glabrata as its primary intermediate host. It has been proposed that the transition from the free-living S. mansoni miracidium to parasitic mother sporocyst depends on uptake of biogenic amines, e.g. serotonin, from the snail host. However, little is known about potential sources of serotonin in B. glabrata tissues. This investigation examined the localization of serotonin-like immunoreactivity (5HTli) in the central nervous system (CNS) and peripheral tissues of B. glabrata. Emphasis was placed on the cephalic and anterior pedal regions that are commonly the sites of S. mansoni miracidium penetration. The anterior foot and body wall were densely innervated by 5HTli fibers but no peripheral immunoreactive neuronal somata were detected. Within the CNS, clusters of 5HTli neurons were observed in the cerebral, pedal, left parietal, and visceral ganglia, suggesting that the peripheral serotonergic fibers originate from the CNS. Double-labeling experiments (biocytin backfill × serotonin immunoreactivity) of the tentacular nerve and the three major pedal nerves (Pd n. 10, Pd n. 11, and Pd n. 12) disclosed central neurons that project to the cephalopedal periphery. Overall, the central distribution of 5HTli neurons suggests that, as in other gastropods, serotonin regulates the locomotion, reproductive, and feeding systems of Biomphalaria. The projections to the foot and body wall indicate that serotonin may also participate in defensive, nociceptive, or inflammation responses. These observations identify potential sources of host-derived serotonin in this parasite-host system. Inc.

  15. Mapping Soil Transmitted Helminths and Schistosomiasis under Uncertainty: A Systematic Review and Critical Appraisal of Evidence

    PubMed Central

    Hamm, Nicholas A. S.; Soares Magalhães, Ricardo J.; Stein, Alfred

    2016-01-01

    Background Spatial modelling of STH and schistosomiasis epidemiology is now commonplace. Spatial epidemiological studies help inform decisions regarding the number of people at risk as well as the geographic areas that need to be targeted with mass drug administration; however, limited attention has been given to propagated uncertainties, their interpretation, and consequences for the mapped values. Using currently published literature on the spatial epidemiology of helminth infections we identified: (1) the main uncertainty sources, their definition and quantification and (2) how uncertainty is informative for STH programme managers and scientists working in this domain. Methodology/Principal Findings We performed a systematic literature search using the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) protocol. We searched Web of Knowledge and PubMed using a combination of uncertainty, geographic and disease terms. A total of 73 papers fulfilled the inclusion criteria for the systematic review. Only 9% of the studies did not address any element of uncertainty, while 91% of studies quantified uncertainty in the predicted morbidity indicators and 23% of studies mapped it. In addition, 57% of the studies quantified uncertainty in the regression coefficients but only 7% incorporated it in the regression response variable (morbidity indicator). Fifty percent of the studies discussed uncertainty in the covariates but did not quantify it. Uncertainty was mostly defined as precision, and quantified using credible intervals by means of Bayesian approaches. Conclusion/Significance None of the studies considered adequately all sources of uncertainties. We highlighted the need for uncertainty in the morbidity indicator and predictor variable to be incorporated into the modelling framework. Study design and spatial support require further attention and uncertainty associated with Earth observation data should be quantified. Finally, more attention

  16. On co-design of filter and fault estimator against randomly occurring nonlinearities and randomly occurring deception attacks

    NASA Astrophysics Data System (ADS)

    Hu, Jun; Liu, Steven; Ji, Donghai; Li, Shanqiang

    2016-07-01

    In this paper, the co-design problem of filter and fault estimator is studied for a class of time-varying non-linear stochastic systems subject to randomly occurring nonlinearities and randomly occurring deception attacks. Two mutually independent random variables obeying the Bernoulli distribution are employed to characterize the phenomena of the randomly occurring nonlinearities and randomly occurring deception attacks, respectively. By using the augmentation approach, the co-design problem of the robust filter and fault estimator is converted into the recursive filter design problem. A new compensation scheme is proposed such that, for both randomly occurring nonlinearities and randomly occurring deception attacks, an upper bound of the filtering error covariance is obtained and such an upper bound is minimized by properly designing the filter gain at each sampling instant. Moreover, the explicit form of the filter gain is given based on the solution to two Riccati-like difference equations. It is shown that the proposed co-design algorithm is of a recursive form that is suitable for online computation. Finally, a simulation example is given to illustrate the usefulness of the developed filtering approach.

  17. Cx3cr1 deficiency in mice attenuates hepatic granuloma formation during acute schistosomiasis by enhancing the M2-type polarization of macrophages.

    PubMed

    Ran, Lin; Yu, Qilin; Zhang, Shu; Xiong, Fei; Cheng, Jia; Yang, Ping; Xu, Jun-Fa; Nie, Hao; Zhong, Qin; Yang, Xueli; Yang, Fei; Gong, Quan; Kuczma, Michal; Kraj, Piotr; Gu, Weikuan; Ren, Bo-Xu; Wang, Cong-Yi

    2015-07-01

    Acute schistosomiasis is characterized by pro-inflammatory responses against tissue- or organ-trapped parasite eggs along with granuloma formation. Here, we describe studies in Cx3cr1(-/-) mice and demonstrate the role of Cx3cr1 in the pathoetiology of granuloma formation during acute schistosomiasis. Mice deficient in Cx3cr1 were protected from granuloma formation and hepatic injury induced by Schistosoma japonicum eggs, as manifested by reduced body weight loss and attenuated hepatomegaly along with preserved liver function. Notably, S. japonicum infection induced high levels of hepatic Cx3cr1 expression, which was predominantly expressed by infiltrating macrophages. Loss of Cx3cr1 rendered macrophages preferentially towards M2 polarization, which then led to a characteristic switch of the host immune defense from a conventional Th1 to a typical Th2 response during acute schistosomiasis. This immune switch caused by Cx3cr1 deficiency was probably associated with enhanced STAT6/PPAR-γ signaling and increased expression of indoleamine 2,3-dioxygenase (IDO), an enzyme that promotes M2 polarization of macrophages. Taken together, our data provide evidence suggesting that CX3CR1 could be a viable therapeutic target for treatment of acute schistosomiasis.

  18. Cx3cr1 deficiency in mice attenuates hepatic granuloma formation during acute schistosomiasis by enhancing the M2-type polarization of macrophages

    PubMed Central

    Ran, Lin; Yu, Qilin; Zhang, Shu; Xiong, Fei; Cheng, Jia; Yang, Ping; Xu, Jun-Fa; Nie, Hao; Zhong, Qin; Yang, Xueli; Yang, Fei; Gong, Quan; Kuczma, Michal; Kraj, Piotr; Gu, Weikuan; Ren, Bo-Xu; Wang, Cong-Yi

    2015-01-01

    ABSTRACT Acute schistosomiasis is characterized by pro-inflammatory responses against tissue- or organ-trapped parasite eggs along with granuloma formation. Here, we describe studies in Cx3cr1−/− mice and demonstrate the role of Cx3cr1 in the pathoetiology of granuloma formation during acute schistosomiasis. Mice deficient in Cx3cr1 were protected from granuloma formation and hepatic injury induced by Schistosoma japonicum eggs, as manifested by reduced body weight loss and attenuated hepatomegaly along with preserved liver function. Notably, S. japonicum infection induced high levels of hepatic Cx3cr1 expression, which was predominantly expressed by infiltrating macrophages. Loss of Cx3cr1 rendered macrophages preferentially towards M2 polarization, which then led to a characteristic switch of the host immune defense from a conventional Th1 to a typical Th2 response during acute schistosomiasis. This immune switch caused by Cx3cr1 deficiency was probably associated with enhanced STAT6/PPAR-γ signaling and increased expression of indoleamine 2,3-dioxygenase (IDO), an enzyme that promotes M2 polarization of macrophages. Taken together, our data provide evidence suggesting that CX3CR1 could be a viable therapeutic target for treatment of acute schistosomiasis. PMID:26035381

  19. MicroR-146 blocks the activation of M1 macrophage by targeting signal transducer and activator of transcription 1 in hepatic schistosomiasis.

    PubMed

    He, Xing; Tang, Rui; Sun, Yue; Wang, Yan-Ge; Zhen, Kui-Yang; Zhang, Dong-Mei; Pan, Wei-Qing

    2016-11-01

    Schistosomiasis is a chronic disease caused by the parasite of the Schistosoma genus and is characterized by egg-induced hepatic granulomas and fibrosis. Macrophages play a central role in schistosomiasis with several studies highlighting their differentiation into M2 cells involved in the survival of infected mice through limitation of immunopathology. However, little is known regarding the mechanisms of regulating macrophage differentiation. Here, we showed that the early stage of infection by Schistosoma japonicum induced expression of type 1T-helper-cell (Th1) cytokine, interferon-γ (IFN-γ), leading to increase in M1 cells. However, the presence of liver-trapped eggs induced the expression of Th2 cytokines including interleukin-4 (IL-4), IL-10, and IL-13 that upregulated the transcription of miR-146b by activating signal transducer and activator of transcription 3/6 (STAT3/6) that bind to the promoter of the pre-miR-146b gene. We found that the miR-146a/b was significantly upregulated in macrophages during the progression of hepatic schistosomiasis. The elevated miR-146a/b inhibited the IFN-γ-induced differentiation of macrophages to M1 cells through targeting STAT1. Our data indicate the protective roles of miR-146a/b in hepatic schistosomiasis through regulating the differentiation of macrophages into M2 cells.

  20. National survey data for zoonotic schistosomiasis in the Philippines grossly underestimates the true burden of disease within endemic zones: implications for future control.

    PubMed

    Olveda, Remigio M; Tallo, Veronica; Olveda, David U; Inobaya, Marianette T; Chau, Thao N; Ross, Allen G

    2016-04-01

    Zoonotic schistosomiasis has a long endemic history in the Philippines. Human mass drug administration has been the cornerstone of schistosomiasis control in the country for the past three decades. Recent publications utilizing retrospective national survey data have indicated that the national human prevalence of the disease is <1%, hence the disease is now close to elimination. However, the evidence for such a claim is weak, given that less than a third of the human population is currently being treated annually within endemic zones and only a third of those treated actually swallow the tablets. For those who consume the drug at the single oral dose of 40mg/kg, the estimated cure rate is 52% based on a recent meta-analysis. Thus, approximately 5% of the endemic human population is in reality receiving the appropriate treatment. To compound this public health problem, most of the bovines in the endemic communities are concurrently infected but are not treated under the current national control programme. Given this evidence, it is believed that the human prevalence of schistosomiasis within endemic regions has been grossly underestimated. Inherent flaws in the reporting of national schistosomiasis prevalence data are reported here, and the problems of utilizing national retrospective data in making geographic information system (GIS) risk maps and advising policy makers of the outcomes are highlighted.

  1. Assessment of schistosomiasis prevalence among children 5 to 14 years old after several years of mass drug administration in the Senegal River basin

    PubMed

    Abdellahi, Moussa; Ndir, Oumar; Niang, Saidou

    2016-10-19

    Introduction: The advent of Diama and Manantali dams in the eighties has altered the schistosomiasis profile in the Senegal River Basin, with the appearance of an intestinal form in the Delta and a high prevalence of the urinary form in all ecological areas of the basin. Methods: The present study was mainly designed to re-evaluate the prevalence of schistosomiasis after many years of mass drug administration with praziquantel 600 mg allowing analysis of the pertinence of World Health Organisation guidelines in terms of dosing frequency, particularly in the Senegal River Basin. Stools and urine from 1,215 public school children from 24 villagesidentified in three ecological areas of the Senegal River Basin (Delta, valley, upper basin), were examined. Results: The results of thisstudy show the endemic prevalences of urinary schistosomiasisin all ecological areas ofthe Senegal River Basin: 57.4% in the Delta, 32.5% in the Valley and 25.1% in the upper basin. The prevalence of the intestinalschistosomiasisform was 21.8 % in the Delta, and this form has also entered the valley. Conclusion: The results ofthisstudy confirm that schistosomiasis is still a public health problem in the Senegal River Basin despite several series of mass praziquantel 600 mg administration. This situation requires detailed reflection concerning dosing frequencies of this drug in the Senegal River basin and the need to take social behaviours and sociological realities into account in order to eradicate schistosomiasis.

  2. 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

    PubMed Central

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

    2017-01-01

    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. PMID:28327791

  3. Rapid, low-cost, two-step method to screen for urinary schistosomiasis at the district level: the Kilosa experience.

    PubMed

    Lengeler, C; Kilima, P; Mshinda, H; Morona, D; Hatz, C; Tanner, M

    1991-01-01

    The operational and diagnostic performance of a two-step method for the cost-effective screening of urinary schistosomiasis was investigated in the Kilosa District of east-central Tanzania. In the first step a simple questionnaire was administered to 15,073 primary schoolchildren by their class teachers over a 4-week period. The answers to the questionnaires had a high negative predictive value for schistosomiasis, and this permitted the safe exclusion of schools where the risk of the disease was low. In the second step, the head-teachers of the 49 high-risk schools and of 26 low-risk schools were instructed on the use of reagent sticks to detect haematuria. Each head-teacher then performed this test on 80 children selected at random in their schools (5750 children were screened within 6 weeks). Crosschecks of the results in 18 schools confirmed the reliability of the head-teachers' testing and their findings were therefore used to prepare an epidemiological map of the district and to arrange for treatment of positive children. This two-step approach relied entirely on the existing school system and permitted screening of a rural district of area 15,000 km2 (population, 350,000) over a 4-month period at a cost of only US$3000.

  4. Rapid, low-cost, two-step method to screen for urinary schistosomiasis at the district level: the Kilosa experience.

    PubMed Central

    Lengeler, C.; Kilima, P.; Mshinda, H.; Morona, D.; Hatz, C.; Tanner, M.

    1991-01-01

    The operational and diagnostic performance of a two-step method for the cost-effective screening of urinary schistosomiasis was investigated in the Kilosa District of east-central Tanzania. In the first step a simple questionnaire was administered to 15,073 primary schoolchildren by their class teachers over a 4-week period. The answers to the questionnaires had a high negative predictive value for schistosomiasis, and this permitted the safe exclusion of schools where the risk of the disease was low. In the second step, the head-teachers of the 49 high-risk schools and of 26 low-risk schools were instructed on the use of reagent sticks to detect haematuria. Each head-teacher then performed this test on 80 children selected at random in their schools (5750 children were screened within 6 weeks). Crosschecks of the results in 18 schools confirmed the reliability of the head-teachers' testing and their findings were therefore used to prepare an epidemiological map of the district and to arrange for treatment of positive children. This two-step approach relied entirely on the existing school system and permitted screening of a rural district of area 15,000 km2 (population, 350,000) over a 4-month period at a cost of only US$3000. PMID:1907220

  5. Linking Satellite Remote Sensing Based Environmental Predictors to Disease: AN Application to the Spatiotemporal Modelling of Schistosomiasis in Ghana

    NASA Astrophysics Data System (ADS)

    Wrable, M.; Liss, A.; Kulinkina, A.; Koch, M.; Biritwum, N. K.; Ofosu, A.; Kosinski, K. C.; Gute, D. M.; Naumova, E. N.

    2016-06-01

    90% of the worldwide schistosomiasis burden falls on sub-Saharan Africa. Control efforts are often based on infrequent, small-scale health surveys, which are expensive and logistically difficult to conduct. Use of satellite imagery to predictively model infectious disease transmission has great potential for public health applications. Transmission of schistosomiasis requires specific environmental conditions to sustain freshwater snails, however has unknown seasonality, and is difficult to study due to a long lag between infection and clinical symptoms. To overcome this, we employed a comprehensive 8-year time-series built from remote sensing feeds. The purely environmental predictor variables: accumulated precipitation, land surface temperature, vegetative growth indices, and climate zones created from a novel climate regionalization technique, were regressed against 8 years of national surveillance data in Ghana. All data were aggregated temporally into monthly observations, and spatially at the level of administrative districts. The result of an initial mixed effects model had 41% explained variance overall. Stratification by climate zone brought the R2 as high as 50% for major zones and as high as 59% for minor zones. This can lead to a predictive risk model used to develop a decision support framework to design treatment schemes and direct scarce resources to areas with the highest risk of infection. This framework can be applied to diseases sensitive to climate or to locations where remote sensing would be better suited than health surveys.

  6. Refolding of the recombinant protein Sm29, a step toward the production of the vaccine candidate against schistosomiasis.

    PubMed

    Chura-Chambi, Rosa M; Nakajima, Erika; de Carvalho, Roberta R; Miyasato, Patricia A; Oliveira, Sergio C; Morganti, Ligia; Martins, Elizabeth A L

    2013-12-01

    Schistosomiasis is an important parasitic disease, with about 240 million people infected worldwide. Humans and animals can be infected, imposing an enormous social and economic burden. The only drug available for chemotherapy, praziquantel, does not control reinfections, and an efficient vaccine for prophylaxis is still missing. However, the tegumental protein Sm29 of Schistosoma mansoni was shown to be a promising antigen to compose an anti-schistosomiasis vaccine. Though, recombinant Sm29 is expressed in Escherichia coli as insoluble inclusion bodies requiring an efficient process of refolding, thus, hampering its production in large scale. We present in this work studies to refold the recombinant Sm29 using high hydrostatic pressure, a mild condition to dissociate aggregated proteins, leading to refolding on a soluble conformation. Our studies resulted in high yield of rSm29 (73%) as a stably soluble and structured protein. The refolded antigen presented protective effect against S. mansoni development in immunized mice. We concluded that the refolding process by application of high hydrostatic pressure succeeded, and the procedure can be scaled-up, allowing industrial production of Sm29.

  7. Media independent interface

    NASA Technical Reports Server (NTRS)

    1987-01-01

    The work done on the Media Independent Interface (MII) Interface Control Document (ICD) program is described and recommendations based on it were made. Explanations and rationale for the content of the ICD itself are presented.

  8. Allergies and Asthma: They Often Occur Together

    MedlinePlus

    ... occur together. The same substances that trigger your hay fever symptoms, such as pollen, dust mites and pet ... a major risk factor for allergic asthma. Having hay fever or other allergies yourself also increases your risk ...

  9. Naturally Occurring Radon and 120(h) transfers

    EPA Pesticide Factsheets

    This page contains a discussion regarding how the presence of naturally occurring radon on closing military bases affects the United States' ability to transfer parcels under §120(h) (3) and §120(h) (4).

  10. Schistosomiasis Prevalence and Intensity of Infection in Latin America and the Caribbean Countries, 1942-2014: A Systematic Review in the Context of a Regional Elimination Goal

    PubMed Central

    2016-01-01

    Background In 2012 the World Health Assembly adopted resolution WHA65.21 on elimination of schistosomiasis, calling for increased investment in schistosomiasis control and support for countries to initiate elimination programs. This study aims to analyze prevalence and intensity of Schistosoma mansoni infection in children in Latin America and the Caribbean countries and territories (LAC), at the second administrative level or lower. Methodology A systematic review of schistosomiasis prevalence and intensity of infection was conducted by searching at PubMed, LILACS and EMBASE. Experts on the topic were informally consulted and institutional web pages were reviewed (PAHO/WHO, Ministries of Health). Only SCH infection among children was registered because it can be a ‘proxi-indicator’ of recent transmission by the time the study is conducted. Principal Findings One hundred thirty two full-text articles met the inclusion criteria and provided 1,242 prevalence and 199 intensity of infection data points. Most of them were from Brazil (69.7%). Only Brazil published studies after 2001, showing several 'hot spots' with high prevalence. Brazil, Venezuela, Suriname and Saint Lucia need to update the epidemiological status of schistosomiasis to re-design their national programs and target the elimination of Schistosoma mansoni transmission by 2020. In Antigua and Barbuda, Dominican Republic, Guadeloupe, Martinique, Montserrat and Puerto Rico schistosomiasis transmission may be interrupted. However the compilation of an elimination dossier and follow-up surveys, per WHO recommendations, are needed to verify that status. Hence, the burden of subtle SCH chronic infection may be still present and even high in countries that may have eliminated transmission. Heterogeneity in the methodologies used for monitoring and evaluating the progress of the schistosomiasis programs was found, making cross-national and chronological comparisons difficult. Conclusions There is a need for

  11. Molten Metal Explosions are Still Occurring

    DTIC Science & Technology

    2009-02-01

    recycling plant. Another recent 665 Light Metals 2009 Edited by: Geoff Bearne TMS (The Minerals, Metals & Materials Society), 2009 catastrophic...occurred recently in a recycling plant casting small ingots over a water tank. An explosion <