Molecular detection of feline viruses in free-ranging European wildcats (Felis s. silvestris) of the Harz Mountains, Germany.

Many infectious diseases commonly affecting domestic cats may pose potential threats to wild felid populations. Several established contagious feline viruses - including feline leukemia virus (FeLV), feline immunodeficiency virus (FIV), feline coronavirus (FCoV), feline calicivirus (FCV), feline herpesvirus (FHV), and feline parvovirus (FPV) - are well-known drivers of disease epidemiology. In addition, recently identified agents such as feline circovirus (FeCV), feline morbillivirus (FeMV) and other novel paramyxoviruses as well as polyomaviruses may represent emerging risks to wild populations. We conducted a comprehensive molecular epidemiological survey to investigate the occurrence of these viruses in free-ranging European wildcats (Felis s. silvestris) from the Harz Mountains, a low mountain range in central Germany. A total of 42 individuals were sampled between 2010 and 2018. Molecular screening was performed using a comprehensive set of conventional PCR, reverse transcription PCR (RT-PCR), and quantitative RT-PCR (qRT-PCR) assays to detect viral nucleic acids. FeLV DNA was detected in 5/42 individuals (11.90%), and FPV DNA was detected in 2/42 wildcats (4.76%). Overall, viral nucleic acid was identified in seven animals (16.67%). No evidence of the remaining target viruses was found using the respective (q)RT-PCR and conventional PCR assays. However, negative PCR results should be interpreted with caution due to the exclusive use of long-term ethanol-preserved spleen samples, which may have reduced analytical sensitivity. The findings provide molecular evidence of FPV and FeLV, in free-ranging European wildcats in the Harz Mountains. Continued surveillance remains essential to better understand pathogen dynamics, evaluate potential spillover from domestic cats, and inform conservation strategies aimed at safeguarding wild felid populations in Central Europe.