A One-Year Retrospective Analysis of Viral and Parasitological Agents in Wildlife Animals Admitted to a First Aid Hospital

Simple Summary In recent decades, wildlife populations in Italy have continued to expand, and some species are now present in large numbers with a wide geographical distribution. Viral and parasitic agents are an integral part of any wildlife population. The major changes in human land use, the tendency of some wild animals to get closer to urban areas in search of food, the increased interest in visiting protected natural areas, and the hunting of game as a food source increase the possibility of sharing natural areas between wild animals, livestock, pets, and humans. From an epidemiological point of view, these factors also increase the possibility of the exchange of pathogens between these groups. Therefore, wild animals can act as a source of infection for domestic animals and humans. This study represents a retrospective analysis including viral agents and parasites affecting a cohort of wild animals in Italy, providing a comprehensive overview of their health status. Overall, a large number of animals tested positive for at least one pathogen, and many were infected with more than two agents, showing a wide range of pathogens responsible for intra- and interspecific transmission in wild populations living in the study areas. This study aimed to provide information on the presence and frequency of viral and parasitic agents in wildlife presented to a Veterinary Teaching Hospital in 2020-2021. Serum and faecal samples were collected from 50 rescued animals (roe deer, fallow deer, foxes, badgers, pine martens, and porcupines) and examined by serological, molecular, and parasitological techniques. Transtracheal wash (TTW) was also collected post-mortem from roe deer. Overall, the results of the different techniques showed infections with the following viral and parasitic agents: Bovine Viral Diarrhea Virus, Small Ruminant Lentiviruses, Kobuvirus, Astrovirus, Canine Adenovirus 1, Bopivirus, gastrointestinal strongyles, Capillaria, Ancylostomatidae, Toxocara canis, Trichuris vulpis, Hymenolepis, Strongyloides, Eimeria, Isospora, Dictyocaulus, Angiostrongylus vasorum, Crenosoma, Dirofilaria immitis, Neospora caninum, Giardia duodenalis, and Cryptosporidium. Sequencing (Tpi locus) identified G. duodenalis sub-assemblages AI and BIV in one roe deer and one porcupine, respectively. Adult lungworms collected from the TTW were identified as Dictyocaulus capreolus (COX1 gene). This is the first molecular identification of G. duodenalis sub-assemblage AI and D. capreolus in roe deer in Italy. These results show a wide presence of pathogens in wild populations and provide an overview of environmental health surveillance.