DNA barcoding of Iranian radicine freshwater snails begins to untangle the taxonomy and phylogeography of intermediate hosts of schistosomiasis and fasciolosis from the Middle East and across Central Asia.

In the Middle East radicine snails are of considerable medical and veterinary importance acting as vectors of trematodes. In Iran, such snails are responsible for the transmission of the zoonotic trematodes Schistosoma turkestanicum and Fasciola gigantica. Historically, Radix gedrosiana has been incriminated as an important intermediate host for both trematodes, however, controversy remains over the snail's true taxonomic status. This species has been determined using morphological characters that has resulted in erroneous identification of species, affecting understanding of population biology, and ultimately affecting vector incrimination. In this current study DNA barcoding using cox1 and phylogenetic analyses revealed that snails identified as R. gedrosiana from Iran split into two separate species, Radix euphratica and Ampullaceana sp. The cox1 also provided useful insights into the evolutionary history of R. euphratica populations. Phylogeographic analyses indicated that R. euphratica had an Iraqi/Iranian origin approximately 3.3 MYA and exists as a large stable population across the Middle East and Central Asia, and a lack of genetic differentiation between geographical isolates. Such molecular barcoding techniques are crucial for the identification of radicine snails of Iran being invaluable for the monitoring of zoonotic flukes, understanding the distribution of infection and the accurate incrimination of snail vectors.

The disease is another: therapeutic itinerary of bovine fascioliosis inRionegro (Antioquia) / La enfermedad es otra: itinerario terapéutico de la fasciolosis bovina enRionegro (Antioquia) / A doença é outra: itinerário terapêutico de fasciolose bovina em Rionegro(Antioquia)

This article presents results of an anthropological research project that was carried out in the municipality ofRionegro in the department of Antioquia, Colombia. The disease caused by hepatic fasciola, a parasite native toEurope, and is now present on every continent and is considered to be the pathogenic disease with the greatestlatitudinal, longitudinal, and altitudinal distribution. There are no specific observable symptoms in infected animals that allow a diagnosis, which must be done in veterinary laboratories, which is scarcely ever the case given that thedisease rarely causes death. Through the use of ethnographic methods the researchers accessed various interlocutors linked to the pecuary field, which relayed their interpretations about bovine fasciolosis and about the common practices dealing with it ranging from lay knowledge to dialogues with expert and professional understanding. Thetext illustrates the therapeutic itinerary that is undertaken when certain changes in behavior and appearance areperceived, it describes the course of action that is followed in order to restore the animals’ health, and it considers the decisions that livestock farmers take when cures fail, all of which are the result of the fact that it is not mandatory to declare bovine fasciolosis. Academics in the field of national veterinary medicine who research the basic aspects related to the parasite’s life cycle are not familiar with the lay knowledge produced about this disease. An analysis of this knoweldge could contribute to the design of control strategies given that it presents in detail the doubts anduncertainties that have historically surrounded fasciolosis. The tendency to conceive it as a “new” disease, and the scarce attention that it has received in comparison with other livestock diseases that are well-defined in sanitation plans work against the control and prevention of fasciolosis in social practices of bovine livestock management inthe area under study.

Se presentan resultados de una investigación antropológica realizada en el municipio de Rionegro, departamentode Antioquia, Colombia. La enfermedad ocasionada por Fasciola hepatica, un parásito originario de Europa, seencuentra en la actualidad en todos los continentes y es considerada la enfermedad patogénica transmitida porvectores de mayor distribución latitudinal, longitudinal y altitudinal. En los animales infectados no se observansíntomas específicos que faciliten el diagnóstico, este debe hacerse en un laboratorio veterinario, al que en muypocas ocasiones se recurre, debido a que la dolencia rara vez causa la muerte. Mediante el método etnográfico los investigadores accedieron a diferentes interlocutores ligados al ámbito pecuario que expresan sus interpretaciones acerca de la fasciolosis bovina y de las prácticas corrientes para enfrentarla desde el conocimiento lego, en diálogo con el conocimiento profesional o experto. El texto ilustra el itinerario terapéutico iniciado al percibir ciertos cambios en el comportamiento y en el aspecto de los animales, describe el curso de acción para restituír la salud de éstos y se detiene en las decisiones que toman los ganaderos ante el fracaso de la cura, todo ello a expensas de que la fasciolosis bovina no constituye una enfermedad de declaración obligatoria.

No presente artigo apresentam-se resultados de uma pesquisa antropológica no município de Rionegro, departamentoou província de Antioquia, Colômbia. A doença produzida pela fasciola hepatica, um parasita originário da Europa,encontra-se atualmente em todos os continentes, sendo considerada uma doença patogênica transmitida por vetores de maior distribuição latitudinal, longitudinal e altitudinal. Nos animais infetados não se observam sintomas específicosque facilitem o diagnóstico, sendo que este dever ser realizado em um laboratório veterinário. Contudo, o diagnóstico é feito com pouca frequência devido a que a doença raramente causa a morte. Mediante o método etnográfico, ospesquisadores entraram em contato com diferentes interlocutores ligados ao âmbito pecuário que expressam suasinterpretações acerca da fasciolose bovina e das práticas mais comuns para enfrentá-la a partir de um conhecimentoleigo que dialoga com o conhecimento profissional ou especializado. Isto tudo à custa do fato de a fasciolose bovina não constituir uma doença que deva ser declarada. Os acadêmicos, no âmbito da medicina veterinária na Colômbia,conhecem os aspectos básicos relacionados com o ciclo de vida do parasita, mas não estão familiarizados como o conhecimento leigo da doença. Um olhar a partir deste aspecto poderia contribuir para a criação de estratégias de controle visto que apresenta, para um público mais amplo, um mundo de dúvidas e incertezas que foi construídohistoricamente em torno da fasciolose. A tendência a concebê-la como uma doença “nova” e a pouca atenção dada,quando comparada com outras doenças do gado definidas nos programas e planos da saúde pública, desfavorecemo controle a prevenção da fasciolose nas práticas sociais de manejo do gado bovino observadas na área de estudo.

Efficacy of some Fasciola gigantica antigens.

The present study tested the antigenic relationship between the three Egyptian strain of Fasciola gigantica antigens; coproantigen, excretory-secretory and egg antigens, versus their related hyper-immune sera and select the most specific one. By using SDS-PAGE, a structural homology was demonstrated in F. gigantica ES and egg antigens. This homology was resided in the components of the similar molecular weights between both antigens. When no cross-reaction was recorded with the coproantigen, the intense cross-reaction occurred between ES and egg antigens in ELISA technique. This was attributed to the presence of common bands at 18.0, 20.4 and 27.6 KDa in between them. Consequently, the F. gigantica coproantigen and Copro HIS reflected the lowest level of the cross-reaction with the other evaluated F. gigantica antigens. The cross-reaction elucidated in the present study between the F. gigantica ES and egg antigens was mainly at the low serum dilutions. The distinction between the specific and the cross-reactive binding activities was clear ly marked with the highly diluted sera.

Attraction to amino acids by Lymnaea acuminata, the snail host of Fasciola species.

Adult Lymnaea acuminata (average length 20-22 mm) were collected locally from lakes and low-lying submerged fields from Gorakhpur. The chemoattraction studies were made in round glass aquaria measuring 30 cm in diameter and filled to a depth of 10 mm with 500 ml dechlorinated tap water. Each aquarium was divided into four concentric zones. At the starting time of the assay 10 snails were placed on the circumference of outermost zone 0. Snail attractant pellets (SAP) were added simultaneously in the center of central zone 3. SAP of different amino acids were prepared at concentrations of 10, 20, 50, 80 and 100 mM/2% agar solution and, subsequently, spread to a uniform thickness of 5 mm. After cooling, SAP were cut in small pieces of 5 mm in diameter. Lymnaea acuminata's attraction to amino acids was studied using different amino acid concentrations in SAP. Pellets containing amino acids with non-polar R groups (proline and tryptophan), a charged polar group (arginine) and uncharged polar R groups (serine, citrulline and asparagine) were tested. The snails were more attracted to the uncharged polar R group amino acid serine than to other groups of amino acids. The preferred amino acid concentration was 80 mM. The attraction of snails to different amino acids was concentration dependent. Snails could discriminate amongst the different amino acids at > or = 50 mM.

Ingestion of Fasciola gigantica metacercariae by the intermediate host snail, Lymnaea ollula, and infectivity of discharged metacercariae.

The rate of ingestion of Fasciola normal metacercariae (NMc) encysted on plants by Lymnaea ollula was examined, and the infectivity of the ingested metacercariae (IMc) in the feces of the host snail to mice was studied. As a result of ingestion by snails, the metacercarial outer cyst disappeared in about 50% of IMc in feces. There was no significant difference in the liver juvenile recovery at autopsy between mice inoculated with NMc and IMc kinds of metacercariae. Compared with NMc, the number of IMc could more easily be counted, because the separation of IMc from fecal contents under a microscope was not laborious.

Experimental infection of rabbits with Fasciola gigantica and treatment with triclabendazole (TCBZ) or BT6: parasitological, haematological and immunological findings.

The responses of rabbits experimentally infected orally with 25 Fasciola gigantica metacercariae each, to treatment with triclabendazole (TCBZ) in a single oral dose of 10 mg/Kg body weight or with the newly synthesized drug (BT6) in repeated oral doses of 500 mg/Kg for 3 consecutive days, were monitored by faecal egg and fluke counts and the enzyme-linked immunosorbent assay (ELISA), both treatments at 4-, 8- and 12- weeks of infection. In all infected rabbits, eggs appeared in the faeces between 10 and 16 weeks post-infection (P1) and Were egg-negative in the TCBZ-treated animals. Compared with the infected untreated control (group B), the reduction in the fluke burdens were 93.75,100 and 100% in TCBZ-treated rabbits (groups C, D and E), respectively and 33.33, 27.08 and 27.08% in the BT6 treated groups F, G and H, respectively. Total red blood corpuscle (RBCs) counts, haemoglobin (Hb) concentration and packed-cell volume (PCV) values in rabbits (group B) indicated the presence of moderate anaemia from the start of infection with a significant decrease from 10-12 weeks onwards. RBCs count, Hb and PCV values from groups C, D and E were significantly higher (p < 0.001) than in those from group B on week 10, 8 and 10 PI, respectively. The increasing was continued till week 16 PI. By two weeks PI there was significant eosinophilia in infected rabbits, maintained at 4 and 6 weeks PI then dropped up to 8 weeks but still statistically higher than the control values. The ELISA detected antibodies against F. gigantica as early as week 2 PI, rising to high levels 6, 10 and 12 weeks later in groups C, D and E, respectively, whilst peaked at 10 weeks in BT6 treated animals, then tended to drop but remained positive through 16 weeks. We conclude TCBZ is a potent fasciolicidic drug. Eosinophilia and anaemia might be indicators for fascioliasis. The ELISA with adult fluke excretory - secretory (ES) antigens could be a feasible method for the diagnosis of experimental fascioliasis in rabbits and post-treatment monitoring.

Clínica y epidemiología de la fasciolasis en los hospitales: Nacional del Sur del IPSS, Goyeneche y Regional Honorio Delgado de Arequipa, agosto de 1970 a enero de 1995

Se realizó un estudio retrospectivo, descriptivo y transversal de Distomatosis mediante la revisión de historias clínicas. Se encontraron 79 casos de Distomatosis Hepática, al revisar 526 historias clínicas cuyo egreso se relacionaba a probable cuadro de Distomatosis. Se siguió los criterios diagnósticos estipulados por Montes(7), Montes, Apaza y Lopera(9) y ratificados por Picoaga(53). En cuanto a la epidemiología, se encontró que el grupo etáreo predominante en nuestro estudio fue el de 20 a 39 años; en lo referente a la ingesta vegetal, la lechuga y el llantén fue la más frecuente; así mismo se encontró que no hay diferencia estadísticamente significativas con relación al sexo(p=0,18). El cuadro clínico estuvo dado fundamentalmente por dolor abdominal tipo cólico, localizado y objetivado con mayor frecuencia en hipocondrio derecho, seguido de hepatomegalia y síntomas de orden general. Se encontró complicaciones de esta parasitosis en fase de invasión, como ruptura hepática espontanea y localización errática cutánea, no se encontró complicaciones en la fase crónica. Se aprecia que la tendencia de esta parasitosis en las dos últimas décadas está disminuyendo, al comparar mediante la prueba T de Student los primeros 12 años con los 12 últimos años, nos muestra una diferencia estadísticamente significativa(p=0,003). El tratamiento fue favorable en los pacientes, predominando el tratamiento con Clorhidrato de Ematina presentando efectos colaterales, en 8 pacientes, los cuales fueron transitorios