Occurrence of Trichinella spp. in Grey Wolves and Red Foxes: Insights from Wild Mammal Surveillance in Emilia-Romagna (Italy)

<i>Trichinella</i> spp. are zoonotic nematodes with a global distribution, primarily maintained through wildlife reservoirs which complicates eradication efforts. In Europe, four species-<i>T. spiralis</i>, <i>T. britovi</i>, <i>T. nativa</i>, and <i>T. pseudospiralis</i>-circulate in wild carnivores and omnivores, with <i>T. britovi</i> and <i>T. spiralis</i> being the most prevalent in wild and domestic hosts. This study aimed to assess the presence and species distribution of <i>Trichinella</i> spp. in wild mammals. This study presents the results of five years of wildlife surveillance carried out within the long-standing monitoring program implemented in the Emilia-Romagna region, northern Italy, which has been in place since 2006. Between 2020 and 2024, a total of 104,338 wild mammals, including red foxes, wolves, and wild boar, were tested using the magnetic stirrer digestion method in accordance with EU regulations. A total of 12 animals (0.011%) were found to be infected with <i>Trichinella</i> larvae. Molecular identification of positive samples, performed at the European Union Reference Laboratory for Parasites, showed the presence of <i>T. britovi</i> in 11 animals, while one isolate remained unidentified. <i>T. britovi</i> was detected primarily in wolves and red foxes. No infections were identified in wild boar during the study period. Overall, the low prevalence observed confirms that <i>Trichinella</i> spp. infections in wildlife in Emilia-Romagna are sporadic but persistently present. Only <i>T. britovi</i> was detected, supporting its role as the predominant species in this area. These findings highlight the importance of long-term surveillance for early detection and risk assessment within a One Health framework.