Preliminary Screening for Selected Viral Pathogens in Red Fox Carcasses from Pisa Province, Italy

Wildlife surveillance contributes to the detection of pathogens of veterinary and zoonotic importance. The red fox (Vulpes vulpes), which is well adapted to human-modified environments, is frequently included in wildlife pathogen surveillance. This preliminary study screened 20 opportunistically collected red fox carcasses from three neighboring areas of Pisa Province, Italy, for selected viral pathogens, including hepatitis E virus (HEV), canine adenovirus (CAdV), canine circovirus (CanineCV), canine parvovirus (CPV), canine coronavirus (CCoV), and canine bocavirus (CBoV), using an integrated serological, molecular, histopathological, and immunohistochemical approach. Five of 20 serum samples showed ELISA reactivity above the applied positive threshold, while two yielded equivocal results. One fecal sample produced an amplification product of the expected size in the HEV nested RT-PCR assay, but Sanger sequencing did not confirm HEV identity. Sequence-confirmed molecular analysis identified CAdV-1 in the liver and CCoV in the feces of the same fox, whereas CPV, CanineCV, and CBoV were not detected. Histopathological findings were nonspecific, and HEV and CAdV immunohistochemistry yielded negative results. These findings represent limited local observations from an opportunistically collected sample and may help inform the design of larger, systematically sampled investigations in red foxes.