Resumo 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.

Abstract 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.

Resumen 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.

Resumo 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.

Abstract 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.

Resumen 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.

Several genes related to the ubiquitin (Ub)-proteasome pathway, including those coding for proteasome subunits and conjugation enzymes, are differentially expressed during the Schistosoma mansoni life cycle. Although deubiquitinating enzymes have been reported to be negative regulators of protein ubiquitination and shown to play an important role in Ub-dependent processes, little is known about their role in S. mansoni . In this study, we analysed the Ub carboxyl-terminal hydrolase (UCHs) proteins found in the database of the parasite’s genome. An in silicoana- lysis (GeneDB and MEROPS) identified three different UCH family members in the genome, Sm UCH-L3, Sm UCH-L5 and SmBAP-1 and a phylogenetic analysis confirmed the evolutionary conservation of the proteins. We performed quantitative reverse transcription-polymerase chain reaction and observed a differential expression profile for all of the investigated transcripts between the cercariae and adult worm stages. These results were corroborated by low rates of Z-Arg-Leu-Arg-Gly-Gly-AMC hydrolysis in a crude extract obtained from cercariae in parallel with high Ub conjugate levels in the same extracts. We suggest that the accumulation of ubiquitinated proteins in the cercaria and early schistosomulum stages is related to a decrease in 26S proteasome activity. Taken together, our data suggest that UCH family members contribute to regulating the activity of the Ub-proteasome system during the life cycle of this parasite.

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.

This study focuses on the geographic distribution of the snail of the genus Biomphalaria and evaluates its infectivity by Schistosoma mansoni in 5264 specimens collected in the municipality of Juiz de Fora, Minas Gerais, Brazil. Of the 31 locations studied, 6 were reservoirs, 11 rudimentary holding ponds, 7 irrigation ditches, 5 lakes, 1 ornamental pond, and 1 waterfall. Intermediate hosts were found only in the rudimentary ponds and ditches, which were 100% positive. Using morphological and molecular analysis techniques, B. tenagophila, B. peregrina, and B. straminea were identified. This is the first report of B. stramínea in the municipality, and evaluation of its infective potential revealed susceptibility of 25.4%. Although we did not find specimens of Biomphalaria infected by S. mansoni, the data obtained indicate the presence of intermediate hosts, especially in the irrigation ditches in Juiz de Fora, and their proximity to contaminated areas.

From complete mitochondrial DNA sequence of Fasciola hepatica available in Genbank, specific primers were designed for a conserved and repetitive region of this trematode. A pair of primers was used for diagnosis of infected Lymnaea columella by F. hepatica during the pre-patent period simultaneously with another pair of primers which amplified the internal transcribed spacer (ITS) region of rDNA from L. columella in a single Multiplex-PCR. The amplification generated a ladder band profile specific for F. hepatica. This profile was observed in positive molluscs at different times of infection, including adult worms from the trematode. The Multiplex-PCR technique showed to be a fast and safe tool for fascioliasis diagnosis, enabling the detection of F. hepatica miracidia in L. columella during the pre-patent period and identification of transmission areas.

Fascioliasis is a parasitic disease of domestic ruminants that occurs worldwide. The lymnaeid intermediate hosts of Fasciola hepatica include Lymnaea columella, which is widely distributed in Brazil. A colony of L. columella from Belo Horizonte, MG, was reared in our laboratory to be used in studies of the F. hepatica life cycle, the intermediate host-parasite relationship and development of an anti-helminthic vaccine. In the first experiment 1,180 snails were exposed to miracidia of F. hepatica eggs removed from the biliary tracts of cattle from the State of Rio Grande do Sul. In the second and third experiments the snails were exposed to miracidia that had emerged from F. hepatica eggs from Uruguay, maintained in rabbits. The rates of infection in the first, second and third experiments were 0, 42.1 and 0% respectively. Over 15,806 metacercariae were obtained and stored at 4ºC. Four rabbits weighing 1.5 kg each were infected with 32-44 metacercariae and two with 200. Three rabbits begin to eliminate eggs of the parasite in the feces from 84 days after infection onwards. The biological cycle of F. hepatica in L. columella and the rabbit was completed within 124 days.