The liver flukes Fasciola hepatica and Fasciola gigantica
are causative agents of fascioliasis in humans and ruminants,
especially cattle, goat and sheep. The disease has
been traditionally considered to be an important veterinary
disease because of the substantial production and large
economic losses in livestock production. In contrast,
human fascioliasis has been linked to cases among livestock
in the area concerned. However, it has been considered an
increasingly important chronic disease since 1980 (Chen
and Mott, 1990; Esteban et al., 1998; Mas-Coma et al.,
1999).