A loop-mediated isothermal amplification assay for Schistosoma mansoni detection in Biomphalaria spp. from schistosomiasis-endemic areas in Minas Gerais, Brazil.

BACKGROUND: Schistosomiasis a neglected tropical disease  endemic in Brazil. It is caused by the trematode Schistosoma mansoni, which is transmitted by snails of the genus Biomphalaria. Among measures used to control and eliminate schistosomiasis, accurate mapping and monitoring of snail breeding sites are recommended. Despite the limitations of parasitological methods, they are still used to identify infected snails. Loop-mediated isothermal amplification (LAMP) is a sensitive, rapid, and cost-effective diagnostic method for the identification of infected snails. In the work reported here, we aimed to validate the use of LAMP for the detection of S. mansoni in snails of the genus Biomphalaria. METHODS: Snails were collected in five municipalities of the Mucuri Valley and Jequitinhonha Valley regions in the state of Minas Gerais, Brazil. Snails were pooled according to collection site and then squeezed for the detection of S. mansoni and other trematode larvae. Pooled snails were subjected to pepsin digestion and DNA extraction. Molecular assays were performed for species-specific identification and characterization of the samples. A previously described LAMP assay was adapted, evaluated, and validated using laboratory and field samples. RESULTS: Using the parasitological method described here, S. mansoni cercariae were detected in snails from two collection sites, and cercariae of the family Spirorchiidae were found in snails from one site. The snails were identified by polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP). Biomphalaria glabrata, the main snail host of S. mansoni in Brazil, was detected in 72.2% of the collection sites. Biomphalaria kuhniana, which is resistant to S. mansoni infection, was found in the remaining sites. Multiplex, low stringency (LS), and conventional PCR allowed the detection of positive snails in four additional sites. Trematodes belonging to the families Strigeidae and Echinostomatidae were detected by multiplex PCR in two sites. The LAMP assay was effective in detecting the presence of S. mansoni infection in laboratory (7 days post-infection) and field samples with no cross-reactivity for other trematodes. When compared to LS and conventional PCR, LAMP showed 100% specificity, 85.7% sensitivity, and a κ index of 0.88. CONCLUSIONS: Our findings suggest that LAMP is a good alternative method for the detection and monitoring of transmission foci of S. mansoni, as it was three times as effective as the parasitological examination used here for the detection of infection, and is more directly applicable in the field than other molecular techniques.

Progress towards elimination of lymphatic filariasis in the Americas region.

In South and Central America, lymphatic filariasis (LF) is caused by Wuchereria bancrofti, which is transmitted by Culex quinquefasciatus, the only vector species in this region. Of the seven countries considered endemic for LF in the Americas in the last decade, Costa Rica, Suriname and Trinidad and Tobago were removed from the World Health Organization list in 2011. The remaining countries, Brazil, Dominican Republic, Guyana and Haiti, have achieved important progress in recent years. Brazil was the first country in the Americas to stop mass drug administration (MDA) and to establish post-MDA surveillance. Dominican Republic stopped MDA in all LF-endemic foci: La Ciénaga and Southwest passed the third Transmission Assessment Survey (TAS) and the Eastern focus passed TAS-1 in 2018. Haiti passed the TAS and interrupted transmission in >80% of endemic communes, achieving effective drug coverage. Guyana implemented effective coverage in MDAs in 2017 and 2018 and in 2019 scaled up the treatment for 100% of the geographical region, introducing ivermectin in the MDA in order to achieve LF elimination by the year 2026. The Americas region is on its way to eliminating LF transmission. However, efforts should be made to improve morbidity management to prevent disability of the already affected populations.

Geographical distribution of intermediate hosts of Schistosoma mansoni in the states of Paraná, Minas Gerais, Bahia, Pernambuco and Rio Grande do Norte, Brazil, 2012-2014. / Distribuição geográfica dos hospedeiros intermediários do Schistosoma mansoni nos estados do Paraná, Minas Gerais, Bahia, Pernambuco e Rio Grande do Norte, 2012-2014.

OBJECTIVE: to describe the geographical distribution of intermediate hosts of Schistosoma mansoni in five Brazilian states. METHODS: this was a descriptive cross-sectional study; municipalities were selected in the states of Paraná (78), Minas Gerais (120), Bahia (82), Pernambuco (51) , and Rio Grande do Norte (98), for the period 2012 to 2014; these municipalities were chosen because they did not have current records of the presence of snails vectores de S. mansoni. The molluscs were captured and taxonomically identified and examined for S. mansoni cercariae. RESULTS: the work was carried out in 427 municipalities (99.5% of the 429 selected); the presence of mollusks was registered in 300 (70.2%) municipalities; Biomphalaria glabrata were found in 62 (21%) municipalities, B. straminea in 181 (60%), B. tenagophila in three (1%); B. glabrata/B. straminea association was found in 53 municipalities (18%) and B. glabrata/B. tenagophila association in one (0.3%) municipality. CONCLUSION: B. glabrata, B. straminea and B. tenagophila distribution records obtained in this study are consistent with previously known distribution.

Distribuição geográfica dos hospedeiros intermediários do Schistosoma mansoni nos estados do Paraná, Minas Gerais, Bahia, Pernambuco e Rio Grande do Norte, 2012-2014 / Distribución geográfica de los huéspedes intermedios de Schistosoma mansoni en los estados de Paraná, Minas Gerais, Bahia, Pernambuco y Rio Grande do Norte, Brasil, 2012-2014 / Geographical distribution of intermediate hosts of Schistosoma mansoni in the states of Paraná, Minas Gerais, Bahia, Pernambuco and Rio Grande do Norte, Brazil, 2012-2014

Objetivo: descrever a distribuição geográfica dos hospedeiros intermediários do Schistosoma mansoni em cinco estados brasileiros. Métodos: estudo transversal; foram selecionados municípios dos estados do Paraná (78), Minas Gerais (120), Bahia (82), Pernambuco (51) e Rio Grande do Norte (98), nos anos de 2012 a 2014; esses municípios foram escolhidos por não possuírem registros atualizados da presença de caramujos hospedeiros intermediários de S. mansoni; moluscos foram capturados, taxonomicamente identificados e examinados para verificação de cercárias de S. mansoni. Resultados: os trabalhos foram realizados em 427 municípios (99,5% dos 429 selecionados); foi registrada presença de moluscos em 300 (70,2%) municípios e a ocorrência de Biomphalaria glabrata em 62 (21%) municípios, B. straminea em 181 (60%), B. tenagophila em três (1%); associação de B. glabrata/B. straminea foi encontrada em 53 (18%), e de B. glabrata/B. tenagophila em um (0,3%). Conclusão: os registros de B. glabrata, B. straminea e B. tenagophila estão de acordo com a distribuição conhecida.

Objetivo: describir la distribución geográfica de los hospedadores intermediarios de Schistosoma mansoni en cinco estados brasileños. Métodos: estudio epidemiológico transversal; el estudio fue realizado en municipios de los estados de Paraná (78), Minas Gerais (120), Bahia (82), Pernambuco (51) y Rio Grande do Norte (98), entre 2012 y 2014; estos municipios fueron elegidos por no poseer registros actualizados de la presencia de caracoles vectores de S. mansoni; los moluscos fueron capturados, taxonómicamente identificados y examinados para la verificación de cercarias de S. mansoni. Resultados: los trabajos fueron realizados en 427 municipios (99,5% de 429 municipios seleccionados); fue registrada presencia de moluscos en 300 (70,2%) municípios; la presencia de Biomphalaria glabrata fue registrada en 62 (21%) municipios, B. straminea en 181 (60%) y B. tenagophila en três (1%); se observó asociación de B. glabrata con B. straminea en 53 (18%) y de B. glabrata con B. tenagophila en uno (0,3%). Conclusión: los registros de Biomphalaria están de acuerdo con la distribución conocida.

Objective: to describe the geographical distribution of intermediate hosts of Schistosoma mansoni in five Brazilian states. Methods: this was a descriptive cross-sectional study; municipalities were selected in the states of Paraná (78), Minas Gerais (120), Bahia (82), Pernambuco (51) , and Rio Grande do Norte (98), for the period 2012 to 2014; these municipalities were chosen because they did not have current records of the presence of snails vectores de S. mansoni. The molluscs were captured and taxonomically identified and examined for S. mansoni cercariae. Results: the work was carried out in 427 municipalities (99.5% of the 429 selected); the presence of mollusks was registered in 300 (70.2%) municipalities; Biomphalaria glabrata were found in 62 (21%) municipalities, B. straminea in 181 (60%), B. tenagophila in three (1%); B. glabrata/B. straminea association was found in 53 municipalities (18%) and B. glabrata/B. tenagophila association in one (0.3%) municipality. Conclusion: B. glabrata, B. straminea and B. tenagophila distribution records obtained in this study are consistent with previously known distribution.

Pesquisa de ovos de helmintos intestinais nos terminais aeroportuários Carlos Drummond de Andrade (Pampulha) - Belo Horizonte E Tancredo Neves ­ Confins ­ Minas Gerais / Search for intestinal helminth eggs in the airport terminals Carlos Drummond de Andrade (Pampulha), Belo Horizonte and Tancredo Neves, Confins, Minas Gerais, Brazil

Este trabalho, utilizando a técnica de Graham (1941), avaliou a presença de ovos de helmintos intestinais em amostras coletadas em superfícies e objetos de dois terminais aeroportuários de Minas Gerais: Carlos Drummond de Andrade (Pampulha), em Belo Horizonte, e Tancredo Neves em Confins. O interior dos aeroportos foi dividido em três grandes áreas: (1) comum, (2) de embarque e desembarque e (3) restrita a funcionários, além de uma aeronave. As coletas foram realizadas no ano de 2013. Todas as lâminas foram analisadas com a utilização de microscópio binocular nos aumentos de 10X e 40X, pela equipe técnica do Grupo de Pesquisa em Helmintologia e Malacologia Médica do Centro de Pesquisas René Rachou (Fiocruz-Minas) em Belo Horizonte. Os resultados indicaram a ausência de ovos em todas as superfícies e objetos examinados. Com base nos resultados, pode-se inferir que a manutenção, a regularidade da limpeza e a desinfecção dos ambientes dos dois aeroportos foram as principais causas da negatividade dos exames.

Spatial distribution of Lymnaeidae (Mollusca, Basommatophora), intermediate host of Fasciola hepatica Linnaeus, 1758 (Trematoda, Digenea) in Brazil.

Snails of the family Lymnaeidae act as intermediate hosts in the biological cycle of Fasciola hepatica, which is a biological agent of fasciolosis, a parasitic disease of medical importance for humans and animals. The present work aimed to update and map the spatial distribution of the intermediate host snails of F. hepatica in Brazil. Data on the distribution of lymnaeids species were compiled from the Collection of Medical Malacology (Fiocruz-CMM, CPqRR), Collection of Malacology (MZUSP), "SpeciesLink" (CRIA) network and through systematic surveys in the literature. Our maps of the distribution of lymnaeids show that Pseudosuccinea columella is the most common species and it is widespread in the South and Southeast with few records in the Midwest, North and Northeast regions. The distribution of the Galba viatrix, G. cubensis and G. truncatula showed a few records in the South and Southeast regions, they were not reported for the Midwest, North and Northeast. In addition, in the South region there are a few records for G. viatrix and one occurrence of Lymnaea rupestris. Our findings resulted in the first map of the spatial distribution of Lymnaeidae species in Brazil which might be useful to better understand the fasciolosis distribution and delineate priority areas for control interventions.

SPATIAL DISTRIBUTION OF LYMNAEIDAE (MOLLUSCA, BASOMMATOPHORA), INTERMEDIATE HOST OF Fasciola hepatica LINNAEUS, 1758 (TREMATODA, DIGENEA) IN BRAZIL / Distribuição espacial de Lymnaeidae (Mollusca, Basommatophora), hospedeiros intermediários de Fasciola hepatica Linnaeus, 1758 (Trematoda, Digenea) no Brasil

Snails of the family Lymnaeidae act as intermediate hosts in the biological cycle of Fasciola hepatica, which is a biological agent of fasciolosis, a parasitic disease of medical importance for humans and animals. The present work aimed to update and map the spatial distribution of the intermediate host snails of F. hepatica in Brazil. Data on the distribution of lymnaeids species were compiled from the Collection of Medical Malacology (Fiocruz-CMM, CPqRR), Collection of Malacology (MZUSP), “SpeciesLink” (CRIA) network and through systematic surveys in the literature. Our maps of the distribution of lymnaeids show that Pseudosuccinea columella is the most common species and it is widespread in the South and Southeast with few records in the Midwest, North and Northeast regions. The distribution of the Galba viatrix, G. cubensis and G. truncatula showed a few records in the South and Southeast regions, they were not reported for the Midwest, North and Northeast. In addition, in the South region there are a few records for G. viatrix and one occurrence of Lymnaea rupestris. Our findings resulted in the first map of the spatial distribution of Lymnaeidae species in Brazil which might be useful to better understand the fasciolosis distribution and delineate priority areas for control interventions.

Moluscos da família Lymnaeidae são hospedeiros intermediários no ciclo biológico de Fasciola hepatica, agente etiológico da fasciolose, doença parasitária de importância médica para humanos e animais. O presente trabalho teve como objetivo datar e mapear a distribuição espacial dos hospedeiros intermediários de F. hepatica no Brasil. Os dados de distribuição das espécies de limneídeos foram obtidos das Coleções de Malacologia Medica (Fiocruz-CMM, CPqRR) e de Malacologia do Museu de Zoologia da Universidade de São Paulo (MZUSP), rede “SpeciesLink” (CRIA) e através de pesquisas sistemáticas na literatura. Os mapas de distribuição dos limneideos mostram que Pseudosuccinea columella é a espécie mais comum e distribuída nas regiões Sul e Sudeste com poucos registros nas regiões Centro-Oeste, Norte e Nordeste. Além disso, na região Sul os registros para G. viatrix são escassos e existe apenas um único relato de ocorrência para L. rupestris. Os dados obtidos resultaram no primeiro mapa de distribuição espacial das espécies de Lymnaeidae no Brasil, informação básica e relevante para estruturação de políticas de controle da fasciolose humana e animal.

Fasciola hepatica in bovines in Brazil: data availability and spatial distribution.

Fasciolosis is a disease of importance for both veterinary and public health. For the first time, georeferenced prevalence data of Fasciola hepatica in bovines were collected and mapped for the Brazilian territory and data availability was discussed. Bovine fasciolosis in Brazil is monitored on a Federal, State and Municipal level, and to improve monitoring it is essential to combine the data collected on these three levels into one dataset. Data were collected for 1032 municipalities where livers were condemned by the Federal Inspection Service (MAPA/SIF) because of the presence of F. hepatica. The information was distributed over 11 states: Espírito Santo, Goiás, Minas Gerais, Mato Grosso do Sul, Mato Grosso, Pará, Paraná, Rio de Janeiro, Rio Grande do Sul, Santa Catarina and São Paulo. The highest prevalence of fasciolosis was observed in the southern states, with disease clusters along the coast of Paraná and Santa Catarina and in Rio Grande do Sul. Also, temporal variation of the prevalence was observed. The observed prevalence and the kriged prevalence maps presented in this paper can assist both animal and human health workers in estimating the risk of infection in their state or municipality.

Fasciola hepatica IN BOVINES IN BRAZIL: DATA AVAILABILITY AND SPATIAL DISTRIBUTION / Fasciola hepatica em bovinos no Brasil: disponibilidade de dados e distribuição espacial

Fasciolosis is a disease of importance for both veterinary and public health. For the first time, georeferenced prevalence data of Fasciola hepatica in bovines were collected and mapped for the Brazilian territory and data availability was discussed. Bovine fasciolosis in Brazil is monitored on a Federal, State and Municipal level, and to improve monitoring it is essential to combine the data collected on these three levels into one dataset. Data were collected for 1032 municipalities where livers were condemned by the Federal Inspection Service (MAPA/SIF) because of the presence of F. hepatica. The information was distributed over 11 states: Espírito Santo, Goiás, Minas Gerais, Mato Grosso do Sul, Mato Grosso, Pará, Paraná, Rio de Janeiro, Rio Grande do Sul, Santa Catarina and São Paulo. The highest prevalence of fasciolosis was observed in the southern states, with disease clusters along the coast of Paraná and Santa Catarina and in Rio Grande do Sul. Also, temporal variation of the prevalence was observed. The observed prevalence and the kriged prevalence maps presented in this paper can assist both animal and human health workers in estimating the risk of infection in their state or municipality.

A fasciolose é doença de alta importância para a saúde tanto veterinária quanto humana. Pela primeira vez, dados georreferenciados da prevalência de Fasciola hepatica em bovinos foram coletados e mapeados para o território brasileiro e a disponibilidade desses dados discutida. Fasciolose bovina no Brasil é monitorado em nível Federal, Estadual e Municipal, e para melhorar esse monitoramento é preciso juntar os dados dos três níveis para construir um único banco de dados. As informações foram coletadas de 1032 municípios onde fígados bovinos foram condenados por causa de F. hepatica pelo Serviço de Inspeção Federal (MAPA/SIF). Onze estados foram representados: Espírito Santo, Goiás, Minas Gerais, Mato Grosso do Sul, Mato Grosso, Pará, Paraná, Rio de Janeiro, Rio Grande do Sul, Santa Catarina e São Paulo. A prevalência mais alta da fasciolose foi observada nos estados do Sul, com presença de focos da doença ao longo do litoral do Paraná e Santa Catarina e no Rio Grande do Sul. Variação temporal da prevalência também foi observada. Os mapas de prevalência observada e de krigeagem aqui apresentados podem auxiliar a profissionais da área da saúde veterinária e humana a estimar o risco de infecção nos seus estados e/ou municípios.

ocorrência de moluscos do gênero Biomphalaria em parques da cidade de Belo Horizonte, Minas Gerais, Brasil / Occurrence of mollusks, genus Biomphalaria, in parks of the city of Belo Horizonte, Minas Gerais, Brazil

Até pouco tempo a esquistossomose era considerada a mais prevalente endemia entre a população rural de baixa renda, especialmente nos estados do Nordeste e Sudeste do Brasil, sendo por issoclassificada como endemia rural. Estudos recentes têm demonstrado que o perfil epidemiológico desta doença está mudando, uma vez que vem sendo transmitida nas periferias e mesmo dentro de grandes centros urbanos. A cidade de Belo Horizonte-MG tem 71 parques, dos quais 55 são abertos àvisitação pública. Em 31 (43,6por cento) deles há uma ou mais coleções hídricas. O objetivo deste trabalhofoi investigar a presença de moluscos de importância médica nas coleções hídricas destes 31 parques da capital mineira. Foram coletados, em 11 parques, 551 exemplares de Biomphalaria, hospedeiraintermediária do Schistosoma mansoni. Foram também coletados exemplares dos gêneros Drepanotrema sp, Pomacea sp, Melanoides sp, Physa sp e Lymnaea sp, este último hospedeirointermediário de outro parasito causador da fasciolose. Todos os exemplares se mostraram negativos para cercárias de S. mansoni. No entanto, considerando a possível contaminação do meio ambiente com fezes humanas infectadas com ovos de S. mansoni e a presença dos hospedeirosintermediários, estes achados servem de alerta para uma possível instalação do ciclo de transmissão da esquistossomose em parques municipais da cidade de Belo Horizonte.

Angiostrongylus cantonensis (Nematode: Metastrongyloidea) in molluscs from harbour areas in Brazil.

Angiostrongylus cantonensis is the most common aetiological agent of human eosinophilic meningoencephalitis. Following a report indicating the presence of this parasite in Brazil in 2007, the present study was undertaken to investigate the presence of A. cantonensis in the surrounding Brazilian port areas. In total, 30 ports were investigated and the following molluscs were identified: Achatina fulica, Belocaulus sp., Bradybaena similaris sp., Cyclodontina sp., Helix sp., Leptinaria sp., Melampus sp., Melanoides tuberculata, Phyllocaulis sp., Pomacea sp., Pseudoxychona sp., Rhinus sp., Sarasinula marginata, Streptaxis sp., Subulina octona, Succinea sp., Tomigerus sp., Wayampia sp. and specimens belonging to Limacidae and Orthalicinae. Digestion and sedimentation processes were performed and the sediments were examined. DNA was extracted from the obtained larvae and the internal transcribed spacer region 2 was analysed by polymerase chain reaction-restriction fragment length polymorphism after digestion with the endonuclease ClaI. Of the 30 ports investigated in this study, 11 contained molluscs infected with A. cantonensis larvae. The set of infected species consisted of S. octona, S. marginata, A. fulica and B. similaris. A total of 36.6% of the investigated ports were positive for A. cantonensis, indicating a wide distribution of this worm. It remains uncertain when and how A. cantonensis was introduced into South America.

Angiostrongylus cantonensis (Nematode: Metastrongyloidea) in molluscs from harbour areas in Brazil

Angiostrongylus cantonensis is the most common aetiological agent of human eosinophilic meningoencephalitis. Following a report indicating the presence of this parasite in Brazil in 2007, the present study was undertaken to investigate the presence of A. cantonensis in the surrounding Brazilian port areas. In total, 30 ports were investigated and the following molluscs were identified: Achatina fulica, Belocaulus sp., Bradybaena similaris sp., Cyclodontina sp., Helix sp., Leptinaria sp., Melampus sp., Melanoides tuberculata, Phyllocaulis sp., Pomacea sp., Pseudoxychona sp., Rhinus sp., Sarasinula marginata, Streptaxis sp., Subulina octona, Succinea sp., Tomigerus sp., Wayampia sp. and specimens belonging to Limacidae and Orthalicinae. Digestion and sedimentation processes were performed and the sediments were examined. DNA was extracted from the obtained larvae and the internal transcribed spacer region 2 was analysed by polymerase chain reaction-restriction fragment length polymorphism after digestion with the endonuclease ClaI. Of the 30 ports investigated in this study, 11 contained molluscs infected with A. cantonensis larvae. The set of infected species consisted of S. octona, S. marginata, A. fulica and B. similaris. A total of 36.6% of the investigated ports were positive for A. cantonensis, indicating a wide distribution of this worm. It remains uncertain when and how A. cantonensis was introduced into South America.

A geoprocessing approach for studying and controlling schistosomiasis in the state of Minas Gerais, Brazil.

Geographical information systems (GIS) are tools that have been recently tested for improving our understanding of the spatial distribution of disease. The objective of this paper was to further develop the GIS technology to model and control schistosomiasis using environmental, social, biological and remote-sensing variables. A final regression model (R(2) = 0.39) was established, after a variable selection phase, with a set of spatial variables including the presence or absence of Biomphalaria glabrata, winter enhanced vegetation index, summer minimum temperature and percentage of houses with water coming from a spring or well. A regional model was also developed by splitting the state of Minas Gerais (MG) into four regions and establishing a linear regression model for each of the four regions: 1 (R(2) = 0.97), 2 (R(2) = 0.60), 3 (R(2) = 0.63) and 4 (R(2) = 0.76). Based on these models, a schistosomiasis risk map was built for MG. In this paper, geostatistics was also used to make inferences about the presence of Biomphalaria spp. The result was a map of species and risk areas. The obtained risk map permits the association of uncertainties, which can be used to qualify the inferences and it can be thought of as an auxiliary tool for public health strategies.

A geoprocessing approach for studying and controlling schistosomiasis in the state of Minas Gerais, Brazil

Geographical information systems (GIS) are tools that have been recently tested for improving our understanding of the spatial distribution of disease. The objective of this paper was to further develop the GIS technology to model and control schistosomiasis using environmental, social, biological and remote-sensing variables. A final regression model (R² = 0.39) was established, after a variable selection phase, with a set of spatial variables including the presence or absence of Biomphalaria glabrata, winter enhanced vegetation index, summer minimum temperature and percentage of houses with water coming from a spring or well. A regional model was also developed by splitting the state of Minas Gerais (MG) into four regions and establishing a linear regression model for each of the four regions: 1 (R² = 0.97), 2 (R² = 0.60), 3 (R² = 0.63) and 4 (R² = 0.76). Based on these models, a schistosomiasis risk map was built for MG. In this paper, geostatistics was also used to make inferences about the presence of Biomphalaria spp. The result was a map of species and risk areas. The obtained risk map permits the association of uncertainties, which can be used to qualify the inferences and it can be thought of as an auxiliary tool for public health strategies.