Identification of Biomphalaria sp. and other freshwater snails in the large-scale water transposition project in the Northeast of Brazil

The wide eco-bio-social intervention generated by the SaoFrancisco River Integration Project (PISF) may contribute to the dispersion or introduction of schistosomiasis intermediate hosts in areas without prior recording. The objective was to characterize the limnic malacofauna and its distribution along watersheds involved in the PISF. A cross-sectional study based on the collection of mollusks from 33 water bodies, from Aurora, Brejo Santo, Jaguaretama, Jaguaribara, Jati e Mauriti municipalities in the Ceara (CE) State was developed. The conchological characteristics were used to identify snails at the genus level. The snails of the genus Biomphalaria were analyzed for the presence of Schistosoma mansoni cercariae and the molecular identification (only mollusks from Brejo Santo-CE) for differentiation between species. The following species were found: Biomphalaria sp.; Drepanotrema sp.; Melanoides sp.; Physa sp.; and Pomacea sp. Pomacea sp. (75.8%) and Biomphalaria sp. (72.7%) were the most prevalent species. All municipalities showed Biomphalaria sp. Biomphalaria straminea (Porcos Stream) and Biomphalaria kuhniana was identified in the Boi 1 and Cipo reservoirs (Brejo Santo). The evaluated municipalities under the influence of the PISF present areas with potential for schistosomiasis transmission. It is necessary to intensify control actions and health surveillance in these areas

Performance of an Ultra-Sensitive Assay Targeting the Circulating Anodic Antigen (CAA) for Detection of Schistosoma mansoni Infection in a Low Endemic Area in Brazil

Techniques with high sensitivity and specificity are required for an accurate diagnosis in low-transmission settings, where the conventional parasitological methods are insensitive. We determined the accuracy of an up-converting phosphor-lateral flow circulating anodic antigen (UCP-LF CAA) assay in urine and serum for Schistosoma mansoni diagnosis in low-prevalence settings in Ceará, Brazil, before and after praziquantel treatment. Clinical samples of a total of 258 individuals were investigated by UCP-LF CAA, point-of-care—circulating cathodic antigen (POC-CCA), soluble worm antigen preparation (SWAP)-ELISA and Kato-Katz (KK); a selection of 128 stools by real-time PCR technique. Three and 6-weeks after treatment, samples were collected and evaluated by detection Schistosoma circulating antigens (CAA and CCA). The UCP-LF CAA assays detected 80 positives (31%) with urine and 82 positives (31.8%) with serum. The urine POC-CCA and serum SWAP-ELISA assays detected 30 (11.6%) and 107 (40.7%) positives, respectively. The Kato-Katz technique revealed only 4 positive stool samples (1.6%). Among the 128 individuals with complete data records, 19 cases were identified by PCR (14.8%); Sensitivities and specificities of the UCP-LF CAA assays, determined versus a combined reference standard based on CCA/KK/PCR positivity, ranged from 60–68% to 68–77%, respectively. In addition only for comparative purposes, sensitivities of the different assays were determined vs. a comparative reference based on CAA/KK/PCR positivity, showing the highest sensitivity for the urine CAA assay (80%), followed by the serum CAA (70.9%), SWAP-ELISA (43.6%), PCR (34.5%), POC-CCA (29.1%), whilst triplicate Kato-Katz thick smears had a very low sensitivity (3.6%). CAA concentrations were higher in serum than in urine and were significantly correlated. There was a significant decrease in urine and serum CAA levels 3 and 6-weeks after treatment. The UCP-LF CAA assays revealed 33 and 28 S. mansoni-infected patients at the 3- and 6-week post-treatment follow-up, respectively. The UCP-LF CAA assays show high sensitivity for the diagnosis of S. mansoni in low-endemicity settings. It detects a considerably higher number of infections than microscopy, POC-CCA or PCR. Also it shows to be very useful for evaluating cure rates after treatment. Hence, the UCP-LF CAA assay is a robust and promising diagnostic approach in low-transmission settings

Accuracy of the urine point-of-care circulating cathodic antigen assay for diagnosing Schistosomiasis mansoni infection in Brazil: a multicenter study

Secretaria de Vigilância em Saúde / Fundo Nacional de Saúde / Ministério da Saúde - [TED/FNS: 118/2017; SIAFI: 691919 / 25000.479741/2017-05Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Educação em Ambiente e Saúde. Rio de Janeiro, RJ, Brasil.Universidade Federal do Ceará. Departamento de Análises Clínicas e Toxicológicas. Fortaleza, CE, Brasil.Fundação Oswaldo Cruz. Instituto René Rachou. Belo Horizonte, MG, Brasil.Ministério da Saúde. Secretaria de Ciência, Tecnologia, Inovação e Insumos Estratégicos. Instituto Evandro Chagas. Laboratório de Parasitoses Intestinais, Esquistossomose e Malacologia. Ananindeua, PA, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Educação em Ambiente e Saúde. Rio de Janeiro, RJ, Brasil.Universidade Federal do Espírito Santo. Centro de Ciências da Saúde. Unidade de Doenças Infecciosas. Vitória, ES, Brasil / Pontifícia Universidade Católica do Rio Grande do Sul. Laboratório de Parasitologia Biomédica. Porto Alegre, RS, Brasil.Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Salvador, BA, Brasil.Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Salvador, BA, Brasil / Universidade Federal da Bahia. Faculdade de Medicina. Salvador, BA, Brasil / Yale University. School of Public Health. Department of Epidemiology of Microbial Diseases. New Haven, CT, USA.Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Salvador, BA, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Educação em Ambiente e Saúde. Rio de Janeiro, RJ, Brasil.Pontifícia Universidade Católica do Rio Grande do Sul. Laboratório de Parasitologia Biomédica. Porto Alegre, RS, Brasil.Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Salvador, BA, Brasil.Ministério da Saúde. Secretaria de Ciência, Tecnologia, Inovação e Insumos Estratégicos. Instituto Evandro Chagas. Laboratório de Parasitoses Intestinais, Esquistossomose e Malacologia. Ananindeua, PA, Brasil.Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Salvador, BA, Brasil.Pontifícia Universidade Católica do Rio Grande do Sul. Laboratório de Parasitologia Biomédica. Porto Alegre, RS, Brasil.Universidade Federal do Ceará. Departamento de Análises Clínicas e Toxicológicas. Fortaleza, CE, Brasil.Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Salvador, BA, Brasil.Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Salvador, BA, Brasil.Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Salvador, BA, Brasil.Pontifícia Universidade Católica do Rio Grande do Sul. Laboratório de Parasitologia Biomédica. Porto Alegre, RS, Brasil.Fundação Oswaldo Cruz. Instituto René Rachou. Belo Horizonte, MG, Brasil.Background: The World Health Organization recommends a market-ready, urine-based point-of-care diagnostic test for circulating cathodic antigens (CCA) to determine the prevalence of S. mansoni. This study evaluated the performance of the URINE CCA (SCHISTO) ECO TESTE® (POC-ECO), which is currently available in Brazil. Methods: Residents from eight sites with different prevalence estimates provided one urine sample for POC-ECO and one stool sample for Kato-Katz (KK) and Helmintex® (HTX) testing as an egg-detecting reference for infection status. Results: None of the study sites had significantly higher POC-ECO accuracy than KK. Conclusions: POC-ECO is not currently recommended in Brazilian schistosomiasis elimination programs

Evaluation of three methods for parasitological diagnosis of Schistosoma mansoni in low endemic in the State of CearÃ.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel SuperiorA Esquistossomose MansÃnica à uma doenÃa endÃmica em 76 paÃses e territÃrios. Em meados de 2003, calculou-se que 779 milhÃes de pessoas estavam dentro da populaÃÃo de risco para esquistossomose, e 207 milhÃes de pessoas estavam infectadas. O diagnÃstico laboratorial dessa parasitose pode ser realizado atravÃs de mÃtodos parasitolÃgicos de fezes, desde os mais clÃssicos (Kato-Katz), a alguns que ainda estÃo em fase de validaÃÃo. Este estudo foi realizado para avaliar dois novos mÃtodos coproscÃpicos para diagnÃstico da Esquistossomose MansÃnica, em moradores de uma Ãrea de baixa endemicidade no MunicÃpio de Maranguape, no Estado do CearÃ, utilizando o mÃtodo de Kato-Katz como referÃncia e a sorologia (ELISA) para a triagem dos pacientes. Foram desenvolvidas as seguintes etapas: Reconhecimento da Ãrea e divulgaÃÃo do projeto junto aos residentes na localidade; Visita domiciliar para assinatura do termo de consentimento livre e esclarecido e entrevista para coleta de dados epidemiolÃgicos; Coleta de sangue para realizaÃÃo do mÃtodo sorolÃgico; DistribuiÃÃo dos frascos para coleta de fezes, somente para os participantes que foram reativos no teste sorolÃgico; recebimento das amostras de fezes e realizaÃÃo dos mÃtodos coproscÃpicos e por fim, entrega dos resultados dos exames e tratamento dos indivÃduos positivos. Comparando-se os resultados obtidos pelo mÃtodo do Kato-Katz e do Gradiente SalÃnico viu-se que dos 13 positivos (23,2%) encontrados por ambos, 10 (76,9%) foram diagnosticados apenas atravÃs do Gradiente SalÃnico. Jà quando comparou-se o mÃtodo do Kato-Katz e do Helmintex, das 32 amostras analisadas, 16 foram positivos (50%) por ambos, porÃm, 12 (75%) destes indivÃduos foram diagnosticados apenas pelo Helmintex. E ao comparamos o mÃtodo do Gradiente SalÃnico com o Helmintex, nos 32 indivÃduos que realizaram estes, 17 (53%) foram positivos em ambas as tÃcnicas, sendo 11 (64,7%) positivos sà no Helmintex. Assim, os mÃtodos do Gradiente SalÃnico e Helmintex mostraram-se mais efetivos no diagnÃstico da esquistossomose mansÃnica na localidade em estudo, quando comparados ao Kato-Katz, porÃm diante da forma de execuÃÃo das tÃcnicas, as mesmas podem nÃo ser adequadas para grandes inquÃritos epidemiolÃgicos, mas para estudos pontuais em Ãreas onde o programa de controle nÃo consegue atingir os objetivos.The Schistosomiasis is endemic in 76 countries and territories. In mid 2003, it was estimated that 779 million people were within the population at risk for schistosomiasis, 207 million people were infected. The laboratory diagnosis of schistosomiasis can be accomplished through methods for parasites, ranging from classics (Kato-Katz), a few that are still undergoing validation. This study was conducted to evaluate two coproscopic new methods for diagnosis of Schistosomiasis in residents of an area of low endemicity in Maranguape-CearÃ, using the Kato-Katz as a reference and serology (ELISA) for screening of patients. We developed the following steps: knowing the area and dissemination of the project with residents in the locality; Home visit to signing the consent form and interview to collect epidemiologic data, blood collection for performing the serological method, distribution of the bottles for feces, only for participants who were reactive in serological testing, collection of stool samples and carrying out the methods coproscopic and finally, delivery of results of examinations and treatment of positive individuals. Comparing the results obtained by the Kato-Katz method and salt gradient was seen that the 13 positive (23.2%) found by both, 10 (76.9%) were diagnosed only by the saline gradient. Even when we compared the method of Kato-Katz and Helmintex of the 32 samples analyzed, 16 were positive (50%) for both, however, 12 (75%) of these individuals were diagnosed only by Helmintex. And when comparing the method the saline gradient with Helmintex in 32 individuals who completed these, 17 (53%) were positive by both techniques, 11 (64.7%) positive only in Helmintex. Thus, the methods of the Saline Gradiente and Helmintex were more effective in the diagnosis of schistosomiasis in locus study, when compared to the Kato-Katz, but on the way of implementing the techniques, they may not be suitable for large surveys epidemiological, but for specific studies in areas where the driver fails to achieve the goals

Association between allergic responses and Schistosoma mansoni infection in residents in a low-endemic setting in Brazil

Introduction Schistosomiasis is endemic in 76 countries and territories. Several studies have found an inverse correlation between parasitic disease and the development of allergies. The purpose of the present study was to determine whether infection with Schistosoma mansoni in subjects with a low parasite load is protective against allergy. The final sample consisted of 39 S. mansoni-positive and 52 S. mansoni-negative residents of a small community in northeastern Brazil. Methods All subjects were submitted to the Kato-Katz test, anti-S. mansoni IgG measurement, the prick test for aeroallergens, eosinophil counts and serum IgE measurement. Results Subjects who reacted to one or more antigens in the prick test were considered allergic. Only 7 S. mansoni-positive subjects (17.9%) reacted to one or more antigens, whereas 20 S. mansoni-negative subjects (38.5%) tested positive for allergy. Conclusions Our findings suggest that, in areas of low endemicity, infection with S. mansoni significantly reduces the risk of the development of allergy in subjects with a low parasite load

Spatiotemporal patterns of schistosomiasis-related deaths, Brazil, 2000–2011

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