Diagnosis and Risk Factors of Bovine and Human Fascioliasis in Cattle Farms from a Venezuelan Andean Rural Area.

INTRODUCTION: Fascioliasis is caused in Venezuela by the trematode Fasciola hepatica, affecting herbivorous and human. The Venezuelan Andean region is endemic for bovine fascioliasis and its presence in humans is not known. The objective of this work was to detected positive cases of bovine and human fascioliasis by coprological and immunological techniques and determine the possible risk factors, in eight cattle farms of a Venezuelan Andean rural area. METHODS: We studied 143 samples of feces and sera of bovines, and 34 samples of feces and sera of humans. Feces were examined by several coprologic techniques, while sera were evaluated by ELISA using two antigens: crude extract (CE) and surface proteins (SP) of F. hepatica, which were previously standardized and validated. RESULTS: The frequency of fascioliasis in bovines was 21% by coprology, and 49.7% by SP-ELISA. The human detection was 0% by coprology, and 29.4% by SP-ELISA. There were statistical significative differences between cattle farms, regarding to the positive results by coprology and by SP-ELISA. About the possible risk factors, statistical association was found only with the presence of snails near or in the farms and consumption of non-channeled water (river, ditch or spring), both for cattle and for humans. CONCLUSION: The results showed that the studied area is endemic for bovine fascioliasis, the human has been in contact with F. hepatica and there are risk factors for the transmission of the parasite in the studied farms.

Zoonotic Trypanosomes in Rats and Fleas of Venezuelan Slums.

Rattus spp. are reservoirs of many human zoonoses, but their role in domestic transmission cycles of human trypanosomiasis is underestimated. In this study, we report trypanosome-infected Rattus norvegicus and Rattus rattus in human dwellings in slums neighboring Maracay, a large city near Caracas, the capital of Venezuela. Blood samples of R. norvegicus and R. rattus examined by PCR and FFLB (fluorescent fragment length barcoding) revealed a prevalence of 6.3% / 31.1% for Trypanosoma lewisi (agent of rat- and flea-borne human emergent zoonosis), and 10.5% / 24.6% for Trypanosoma cruzi (agent of Chagas disease). Detection in flea guts of T. lewisi (76%) and, unexpectedly, T. cruzi (21.3%) highlighted the role of fleas as carriers and vectors of these trypanosomes. A high prevalence of rats infected with T. lewisi and T. cruzi and respective flea and triatomine vectors poses a serious risk of human trypanosomiasis in Venezuelan slums. Anthropogenic activities responsible for growing rat and triatomine populations within human dwellings drastically increased human exposure to trypanosomes. This scenario has allowed for the reemergence of Chagas disease as an urban zoonosis in Venezuela and can propitiate the emergence of atypical T. lewisi infection in humans.

Prevalencia y Abundancia de Huevos de Estróngilos Digestivos y Ooquistes de Eimeria spp. en Búfalos de Agua Infectados Naturalmente / Prevalence and Abundance of Digestive Strongyles Eggs and Eimeria spp. Oocysts in Water Buffaloes Naturally Infected

La cría de búfalos de agua (Bubalus bubalis) se ha convertido en una ganadería cada vez más importante y común en nuestro país; sin embargo, afecciones como las gastroenteritis parasitarias representan una de las limitantes en el desarrollo de esta especie, provocando un impacto negativo sobre la producción cárnica y lechera. Los principales agentes etiológicos responsables de esta afección son los estróngilos digestivos (Nematoda: Strongylida) y coccidias del género Eimeria (Sporozoa: Eucoccidida). Con el objetivo de determinar el comportamiento de estas infecciones, se evaluaron mediante exámenes coprológicos mensuales a través de la técnica cuantitativa de McMaster, búfalos de cuatro grupos etarios (bumautes entre 8 y 18 meses de edad, bumautes mayores de 18 meses, sementales y búfalas), de ambos sexos, pertenecientes a un rebaño comercial del estado Falcón. Los estróngilos digestivos y las coccidias fueron los más prevalentes, con 25,2 y 46,2%, respectivamente. La abundancia del rebaño fue de 38±41,1 huevos por gramo (HPG) de heces para estróngilos y de 142,4±117,2 ooquistes por gramo (OPG) de heces para coccidias. Hubo diferencias estadísticas (p<0,05) al comparar los valores de prevalencia y abundancia de las infecciones por estróngilos digestivos y coccidias entre los grupos etarios y el sexo. Los valores de prevalencia y abundancia disminuyeron con la edad de los animales evaluados (estróngilos: prevalencias de 39,5; 34,0; 42,3; 15,8% y abundancias de 79,8; 47,2; 30,8; 12,2 HPG; coccidias: prevalencias de 71,3; 54,8; 38,5; 34,0% y abundancias de 379,1; 121,0; 44,2; 47,6 OPG), siendo superiores en machos que en hembras (estróngilos: prevalencias de 36,2 y 22,4%, y abundancias de 70,5 y 30,9 HPG; coccidias: prevalencias de 57,3 y 43,6% y abundancias de 166,3 y 131,5 OPG, respectivamente). Las mayores cargas parasitarias y las infecciones de importancia clínica se observaron en los bumautes entre 8 y 18 meses de edad (contajes mayores a 500 HPG y 5050 OPG). Las condiciones climáticas se encontraron en rangos favorables (25,6-29,3ºC, 77,0-89,0% de humedad relativa y 1,0-151,3 mm de precipitación) para el desarrollo de las formas preparasíticas de estróngilos digestivos y coccidias.

The breeding of water buffaloes (Bubalus bubalis) has become an increasingly important and common livestock in Venezuela; however, conditions such as gastrointestinal parasitism are one of the major constraints in the development of this species, with a negative impact on meat and milk production. The main etiologic agents responsible for this condition are digestive strongyles (Nematoda: Strongylida) and coccidia of the genus Eimeria (Sporozoa: Eucoccidida). This investigation evaluated the behavior of these infections in buffaloes of different age and sex. Samples were collected and examined monthly by the quantitative McMaster technique. The buffaloes were subdivided into four age groups (animals between 8 and 18 months of age, over 18 months, males and female buffaloes), the animals came from a commercial flock of the State of Falcon, Venezuela. The results show that the most prevalent parasites were strongyles and coccidian, 25.2% and 46.2%, respectively. The flock abundance was 38±41.1 eggs per gram (EPG) for strongyles and 142.4±117.2 oocysts per gram (OPG) forcoccidia. There were statistical differences (p <0.05) between age groups and sex of the buffalo, when comparing the values of prevalence and abundance of infections for gastrointestinal strongyles and coccidia. The prevalence and abundance values decreased, with increasing age of the animals tested (strongyles: prevalence of 39.5; 34.0; 42.3; 15.8% and abundance of 79.8; 47.2; 30.8; 12.2 EPG; coccidian: prevalence of 71.3; 54.8; 38.5; 34.0% and abundance of 379.1; 121.0; 44.2; 47.6 OPG), being higher in males than in females (strongyles: prevalence of 36.2 and 22.4%, and abundance of 70.5 and 30.9 EPG; coccidian: prevalence of 57.3 and 43.6% and abundance of 166.3 and 131.5 OPG). The highest parasitic loads and the clinically important infections were seen in 8 to 18 months old buffaloes (counts higher than 500 EPG and 5,050 OPG). Environmental conditions fell within favorable ranges (25.6-29.3ºC of temperature, 77.0-89.0% of relative humidity and 1.0-151.3 mm of precipitation) for the development of infective parasite forms of both digestive strongyles and coccidian.

Parasitismo por estrongilos en caballos salvajes Venezolanos del hato el frío (Edo. Apure, Venezuela): Estudio preliminar / Strongyles parasitism in wild Venezuelan horses from hato el frío, State of Apure, Venezuela: A preliminary study

Los estróngilos son los parásitos más comunes en los caballos, causando serios problemas aún en aquellos animales que reciben tratamiento antihelmíntico. Existe en el país escaso conocimiento del comportamiento de este parasitismo en caballos salvajes cuyas poblaciones de helmintos no están influenciadas por el uso de fármacos antiparasitarios, por lo que el objetivo del presente estudio fue determinar las características de la infección por nematodos Strongylidae en caballos salvajes venezolanos no sometidos a tratamiento antihelmíntico en base a examen coprológico. El estudio se realizó en Abril 2006 en el Hato El Frío, ubicado cerca de Mantecal, estado Apure, Venezuela. Se tomó una muestra de heces directamente del recto a un total de 35 caballos salvajes (21 machos, 14 hembras, representando el 15% de la población), las cuales se procesaron por la técnica de Mc Master modificada y se realizaron cultivos a partir de 4 grupos (pool) de muestras positivas para la identificación de las larvas Strongylidae de tercer estado. Se obtuvo una prevalencia general de 82,86% (29/35) con un promedio general de 818,57 huevos por gramo de heces (hpg) [0-2.300]. De los animales examinados, el 25,71% tenía entre 500 y 1.000 hpg, mientras que 37,14% tenía más de 1.000 hpg. Strongylus vulgaris fue encontrado en 3 de 4 coprocultivos (75%) en porcentajes de 2, 12 y 7%, respectivamente. S. edentatus fue encontrado en 1 de 4 coprocultivos (25%) en porcentaje del 2%. La presencia de grandes estróngilos (S. vulgaris, S. edentatus) encontrados en los coprocultivos fue bastante marcada, así como el significativo número de animales con contajes superiores a 1.000 hpg.

Strongyles are the most common parasites in horses, which can cause serious health problems, even in regularly dewormed horses. There is practically no information in this country on this parasitic infection in wild horses which helminth populations are not influenced by using of antiparasitic drugs. So, the aim of this research was to determinate the caracteristics of Strongylidae nematode infection in wild Venezuelan horses which have never received anthelmintic therapy, on the basis of coprological examination. Study was performed in April 2006 in “Hato El Frío” near to Mantecal, State of Apure, Venezuela. Faecal samples were taken from the rectum, once from each of thirty five randomly selected wild horses (21 males, 14 females), representing approximately 15% of the total population of the herd, and processed using the McMaster modified technique. Four cultures of bulked positive samples for identification of Strongylidae larvae were also performed. General prevalence was 82.86% (29/35), with a general epg mean of 818,57 epg (0-2,300). From the animals sampled 25,71% showed epg counts between 500-1,000 epg but 37,14% had more than 1,000 epg. Strongylus vulgaris was found in 3 out of 4 cultures (75%) in a proportion of 2, 12 and 7%, respectively. Strongylus edentatus was found in 1 out of 4 cultures (25%) in a proportion of 2%. There must be remarkable the presence of large strongyles in cultures as well as the important number of animals harboring more than 1,000 epg.

Parasitismo gastrointestinal en un bioterio canino en venezuela / Canine gastrointestinal parasites in a canine kennel in venezuela

La “Sección de Caninos, Felinos y Batracios” del Bioterio la Facultad de Ciencias Veterinarias de la Universidad Central de Venezuela, cumple un papel fundamental en la docencia y la investigación en esta institución. Las gastroenteritis parasitarias, son uno de los problemas sanitarios en los caninos, cuyo control requiere de la aplicación de medidas integrales, con conocimiento epidemiológico de estas infecciones. Con el objetivo de obtener información acerca de la prevalencia y géneros parasitarios presentes, se llevó a cabo un estudio de la población de este bioterio conformada por 64 caninos mestizos, mayores de un año de edad y de ambos sexos. Mensualmente durante cinco meses, se recolectaron a primera hora de la mañana las heces que estaban presentes en cada jaula, para un total de 141 muestras, que se procesaron mediante las técnicas de Mc Master Modificada y Baerman. Se obtuvo un valor de prevalencia promedio general de infecciones con parásitos gastrointestinales durante todo el estudio de 58,10%, con prevalencias promedio mensuales entre 38,88 y 65,62%. Los valores promedio de prevalencia y rangos correspondientes de acuerdo al tipo de parásitos fueron: nematodes: Ancylostoma spp= 56,59% (33,33 a 65,62%),Strongyloides stercolaris=11,80% (0-25%) y Toxocara spp=3,80% (0-11%); se observaron además ooquistes de protozoarios del género Cystoisospora (Isospora)=19,82% (2-17%). Sólo hubo diferencias en la prevalencia de S. stercolaris  por mes (p<0,05), debido probablemente a la mayor humedad ambiental durante los meses noviembre y diciembre por la presencia de lluvias; no se encontraron diferencias en la prevalencia parasitaria por sexo de hospedador (p>0,05).

The Sección de Caninos, Felinos y Batracios from the Facultad de Ciencias Veterinarias at Universidad Central de Venezuela (UCV) has an important role in teaching and research in the institution. Gastrointestinal parasitism is one of the mayor diseases in canines; therefore, integral control measurements to prevent parasitism must be considered epidemiological knowledge of these parasites. In order to get data about the prevalence and parasites genera present in this population, the examination of 64 dogs of mixed breeds including both genders older than 1 year, was carried out. A total of 141 fecal samples were monthly collected, early in the morning from every cage during 5 months. Samples were processed using both Mc Master and Baerman techniques. The general average prevalence of gastrointestinal parasitism was 58.10%, being between 38.88% and 65.62% monthly. The mean prevalence and ranks according to genera were: Nematoda Ancylostoma spp=56.59% (33.33-65.62%), Strongyloides stercolaris=11.80% (0-25%) and Toxocara spp=3.80% (0-11%). In addition, other classes of parasites were observed: protozoan (coccidian) oocyst Cystoisospora (Isospora)=19.82% (2-17%). There were only differences in the prevalenceof S. stercolaris by month (p<0.05), may be as a consequence of a higher ambient humidity during November and December. There were no differences in the prevalence of parasitism according to the gender of the host.