The red fox, Vulpes vulpes L., as a potential reservoir of zoonotic flukes in the Iberian Peninsula

A parasitological survey of 396 red foxes (Vulpes vulpes L.) from the Principat d'Andorra, 34 Spanish provinces and Serra da Malcata (Portugal) was carried out to evaluate the fluke status of this wild canid in the Iberian Peninsula. Special attention was devoted to the epidemiological role of this canid in maintaining the potential zoonotic distomatosis. Four fluke species were detected: adults of Brachylaima sp., Alaria alata, Opistorchis felineus and Metorchis bilis. Seventeen foxes (4.3%) were infected by at least one of these digeneans. All flukes with an aquatic life cycle were found mainly (26.9%) in a delimited zone (called zone A), characterised by high amount surface water, with A. alata being the most prevalent species (19.2%). Metorchis bilis is more frequently and widely distributed throughout Iberia than O. felineus. Since both flukes have a very similar life cycle, this might be the result of a distinct distribution pattern of their appropriate snails. This study shows that a relatively large natural focus of potential zoonotic flukes (zone A) is located in central Iberia, near the boundary of Portugal with Spain.