Southernmost finding of Lymnaea viatrix orbigny, 1835 (Pulmonata: Lymnaeidae), intermediate host of Fasciola hepatica (Linnaeus, 1758) (Trematoda: Digenea), in urban and rural areas of Patagonia, Argentina

We report the first finding of Lymnaea viatrix south of parallel 41ºS, in rural and urban areas from Argentina. Ninety snails were collected during year 2000, from a concrete pond at a Public Square in El Bolsón Village, Río Negro province, and 811 snails in November 1999, and during 2000 from waterbodies within a farm at Cholila locality, Chubut province. Fasciola hepatica infection was detected in 0.9 percent snails from the rural area. We discuss the potential risk of L. viatrix to public health in urban areas and its epidemiological importance in rural areas of the Andean Patagonian region.

Fasciola hepática (linnaeus, 1758) (trematoda, digenea) en liebres europeas (lepus europaeus, pallas 1778) (lagomorpha, leporidae) en la región Cordillerana Patagónica, Chubut, Argentina / Fasciola hepatica (linnaeus, 1758) (trematoda, digenea) in the hare Lepus europaeus, pallas 1778 (lagomorpha, leporidae) from the Andean Patagonian Region, Chubut Province, Argentina

La liebre europea (Lepus europaeus) ha sido encontrada naturalmente infectada por Fasciola hepatica en varios países, pero en la Argentina no se han realizado estudios al respecto. Este trabajo tuvo por objetivo la búsqueda de infección en liebres de la zona cordillerana de la provincia del Chubut. Durante 1999 se faenaron 162.328 animales provenientes del noroeste de la provincia y se buscaron juveniles y adultos de F. hepatica. En enero y marzo de 2001 se recolectaron boñigas en cuerpos de agua de un establecimiento ganadero de la localidad de Cholila, al noroeste de la provincia del Chubut, donde estudios previos confirmaron la infección en ganado y caracoles. El 0,08 por ciento de las liebres faenadas presentó infección y en el ambiente se encontraron 6/10 boñigas positivas para F. hepatica en un charco (mediana de hpg = 2). A pesar de las bajas prevalencias halladas, el rol de L. europaeus en la transmisión del parásito podría ser importante si se considera que la especie comparte ambientes con el ganado y el caracol, su abundancia es alta, y la densidad de huevos que aporta al medio es mayor que la de bovinos.

First report of Lymnaea columella Say, 1817 (Pulmonata: Lymnaeidae) naturally infected with Fasciola hepatica (Linnaeus,1758) (Trematoda: Digenea) in Argentina

We report the first evidence of natural infection of Lymnaea columella with Fasciola hepatica in Argentina. A sample of 601 snails was collected in May 2003 in northeastern Corrientes, a province bounded on the north by Paraguay, on the east by Brazil and on the southeast by Uruguay. Among 500 examined snails, 44 (8.8 percent) were exclusively infected with F. hepatica. Parasite identification was based on morphological features of cercariae from snails, and of eggs and adult flukes from Wistar rats. We discuss the events suggesting that an enzootic transmission cycle of F. hepatica has been recently established in northeastern Corrientes.