Occurrence of equine parvovirus hepatitis in horses and routes of transmission in hospitalised horses
Equine Parvovirus-Hepatitis (EqPV-H) was first isolated in 2018. It seems to be associated with outbreaks of the potentially fatal serum hepatits, i.e. Theiler´s disease. The disease leads to an acute hepatitis and liver cell necrosis, which can result in liver failure. EqPV-H could be isolated from serum and liver samples of diseased and experimental infected horses, and could be detected in sera of healthy subclinical infected horses with a DNA prevalence up to 17% and an antibody prevalence up to 35%. The iatrogenic transmission via contaminated equine biological products was already shown, while there is also strong evidence for other horizontal transmissions routes, i.e. faecal, nasal and oral shedding.Aims of this research project are: (i) to study the EqPH-H infection status in horses with liver diseases and (ii) to estimate the potential risk for equine patients of getting in contact to EqPV-H in an equine referral clinic.Therefore, (i) stored histopathological changed formalin fixed and paraffin embedded liver tissue samples, will be tested retrospectively for the presence of EqPV-H-DNA by qPCR. Positive tested samples will be further analysed for the localization of the virus by in-situ-hybridisation.In the second part of the project (ii), sera of 100 hospitalized horses (without obvious liver pathologies) will be tested for presence of EqPV-H-DNA by qPCR, as a pilot project. To evaluate potential transmission routes, faeces, nasal secretion and saliva of EqPV-H positive horses will be checked for the presence of EqPV-H-DNA by qPCR as well. Additionally, the EqPV-H positive sera will be screened for the presence of elevated liver enzymes, and for the presence of EqPV-H antibodies by a luciferase immunoprecipitation system (LIPS).This study will shed light on the potential involvement of EqPV-H on other liver pathologies, besides equine serum hepatitis. Furthermore, potential transmission routes of this virus will be evaluated and information about the number of hospitalized horses, which potentially unnoticed shed the virus, will be obtained. This can contribute to improved diagnostic, prophylactic and therapeutic options in horses with liver diseases, and might lead to potentially necessary optimization of the clinic management.