Subclinical infection and potential shedding routes of equine parvovirus-hepatitis among hospitalized horses in Austria.

Background: Equine parvovirus hepatitis (EqPV-H) can cause Theiler's disease and subclinical hepatitis in horses.
Objectives: Assess the frequency of subclinical EqPV-H infection in hospitalized horses and to study viral transmission by investigating potential shedding routes.
Animals: One hundred sixteen equids, that presented to the University Equine Hospital of the University of Veterinary Medicine Vienna between February 2021 and March 2022, for causes other than hepatopathy.
Methods: In this cross-sectional study, samples (serum, feces, nasal, and buccal swabs) of hospitalized horses were collected. Sera were screened for the presence of anti-EqPV-H antibodies by a luciferase immunoprecipitation system assay. Quantitative PCR was used for the detection of EqPV-H DNA in the samples and a nested PCR was used for further validation.
Results: Seroprevalence was 10.3% (12/116) and viremia occurred in 12.9% (15/116) of the serologically positive horses. The detected viral load in serum varied from non-quantifiable amount to 1.3 × 10 ⁶ genome equivalents per milliliter of serum. A low viral load of EqPV-H DNA was detected in 2 nasal swabs and 1 fecal sample.
Conclusion and Clinical Importance: EqPV-H DNA was detected in nasal secretions and feces of viremic horses, which could pose a risk to naive hospitalized horses. It is advisable to screen hospitalized horses that are potential donors of blood or plasma to reduce the risk of iatrogenic EqPV-H transmission.
(© 2024 The Author(s). Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)