Detection of Endoparasites in Non-Native Raccoons from Central Italy

SIMPLE SUMMARY: The raccoon (Procyon lotor) is a carnivore native to North and Central America, gradually introduced into Asia and Europe, including Italy. It is an important carrier of multiple endoparasites, some of them being zoonotic. The aim of this study was to investigate the endoparasites of the non-native raccoon population of Central Italy. The results showed the presence of a number of different Protozoa and Nematodes. Among them, we identified Baylisascaris procyonis, an emerging helminthic zoonotic agent of serious concern for public and animal health, given the possibility of its transmission to paratenic hosts, including humans and pets, at times with severe clinical consequences. The role of the raccoon as a multi-parasite carrier highlights the importance of the eradication/control of this alien species and the need to implement related disease surveillance programs. ABSTRACT: The raccoon (Procyon lotor) is a carnivore native to North and Central America, gradually introduced into Asia and Europe, including Italy. It is an important carrier of multiple endoparasites, both Protozoa and Helminths, some of them being zoonotic. The aim of this study was to investigate the endoparasites of the non-native raccoon population of Central Italy. Sixty-two raccoons were collected by local competent authorities (sixty trapped and euthanized, two found dead) and subjected to necroscopic examination. Carcasses underwent a broad parasitological investigation, including coprological techniques (macroscopic examination of the gastrointestinal tract, lungs, trachea, and heart, Flotac(®), Baermann test, and immunofluorescence for Giardia duodenalis and Cryptosporidium spp.), research on respiratory/urinary capillariosis and artificial digestion for Trichinella spp. larvae, and a histopathological examination of the ileum. Ascarid parasites were further identified at the species level using a next-generation sequencing-based amplicon sequencing approach. The results showed the presence of different Protozoa and Nematodes: Baylisascaris procyonis (26/62; 41.9%), Pearsonema sp. (6/62; 9.6%), Capillariidae (6/62; 9.6%), Eimeria sp. (2/62; 3.2%), Cryptosporidium sp. (2/62; 3.2%), and Ancylostomatidae (2/62; 3.2%). B. procyonis is an emerging helminthic zoonotic agent considered a serious concern for public and animal health, given the possibility of its transmission to paratenic hosts, including humans and pets. The demonstrated role of the raccoon as a multi-parasite carrier should be an incentive to continuing the eradication/control of this alien species, and supports the need to implement related disease surveillance programs.