Cardiopulmonary nematodes of wild carnivores from Denmark: Do they serve as reservoir hosts for infections in domestic animals?

The cardiopulmonary nematodes and , are a cause of concern in the scientific and veterinary community, potentially causing significant disease in domestic animals. To investigate the potential of wild carnivores as reservoir hosts to these parasites, a total of 1041 animals from seven regions of Denmark were sampled: 476 raccoon dogs (), 367 red foxes (), 123 American mink (), 31 beech martens (), 30 Eurasian otters () and 14 polecats (). Hearts and lungs were collected and examined for cardiopulmonary parasites. was identified using morphology, whereas and were identified by a duplex real-time PCR, and by conventional PCR. This is the first Danish report of and infections in raccoon dogs, mink and polecats, and of in raccoon dogs and beech martens. In addition, this is the first time and have been identified in wild animals from the island of Bornholm, just as it is the first report of in American mink, and and in polecats in Europe. The prevalence of appears to have increased in red foxes in Denmark compared to previous studies, while and prevalences are lower. Our data show that several wild carnivores can serve as reservoir hosts for and in Denmark, and that appears more abundant than previously reported. It is speculated that the increase might relate to increased snail abundance, which may be due to a rise in mean yearly temperatures in Denmark.