Detection of equine parvovirus-hepatitis and efficacy of governmental regulation for equine biologics purity.
Abstract: In 2018, a new virus, named equine parvovirus-hepatitis (EqPV-H), was discovered in a biologic product that had been administered to horses that subsequently developed clinical signs of equine serum hepatitis (Theiler disease). Further correlation of the virus with the disease sparked federal requirements that all equine biologics be free of EqPV-H. The initial quantitative real-time PCR (qPCR) test for EqPV-H has proved to be sensitive to co-extracted PCR inhibitors in template nucleic acids, causing false-negative results. We investigated the use of digital PCR (dPCR) as a more robust test. Examination of 227 equine biologic product lots available for purchase both before and after regulatory implementation using both detection methods indicated that dPCR is a more reliable platform. Nevertheless, use of the qPCR method for product screening had reduced the fraction of serials with EqPV-H detected from 39.6% prior to regulation to 6.8% after regulatory implementation. Adoption of dPCR testing is an opportunity to further decrease the prevalence of EqPV-H in equine biologics.
Publication Date: 2024-11-06 PubMed ID: 39506428PubMed Central: PMC11559848DOI: 10.1177/10406387241292343Google Scholar: Lookup
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Summary
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The research article discusses the discovery of a new virus in horses, equine parvovirus-hepatitis (EqPV-H), in 2018, and the subsequent regulatory requirements to ensure all equine biologics are free from EqPV-H. The study found that digital PCR (dPCR) is a more reliable detection method than quantitative real-time PCR (qPCR), despite qPCR being instrumental in reducing the infection rate from 39.6% to 6.8%.
Introduction to EqPV-H and Regulation
- In 2018, a new virus was identified in horses, named equine parvovirus-hepatitis (EqPV-H).
- This virus was discovered in biologic products administered to horses, following which the animals showcased signs of equine serum hepatitis, also known as Theiler disease.
- This discovery instigated federal regulatory requirements to ensure all biologics used in horses were free of EqPV-H to prevent further spread of the disease.
Initial Testing Method
- The first method of testing for EqPV-H was through a technique called quantitative real-time PCR (qPCR).
- However, this method was susceptible to interference by co-extracted PCR inhibitors present in the nucleic acid samples.
- These inhibitors could cause false-negative results, leading to an incorrect assessment of the sample’s EqPV-H status.
Investigation into Digital PCR
- Digital PCR (dPCR) was investigated as an alternative, potentially more robust test for EqPV-H in equine biologics.
- Researchers tested 227 lots of equine biologic products available both before and after the introduction of federal regulation, using both detection methods for comparison.
- The study found that dPCR was a more reliable platform for the detection of EqPV-H than qPCR.
Reduction in EqPV-H and Future Directions
- Despite the limitations in the qPCR method, its use in screening biologic products helped reduce the prevalence of EqPV-H in serials from 39.6% before regulation to 6.8% after regulation was implemented.
- The adoption of dPCR testing in routine screening represents an opportunity to further decrease the prevalence of EqPV-H in equine biologics, strengthening the protection of horses against this virus.
Cite This Article
APA
Scupham AJ, Tong C.
(2024).
Detection of equine parvovirus-hepatitis and efficacy of governmental regulation for equine biologics purity.
J Vet Diagn Invest, 37(1), 79-85.
https://doi.org/10.1177/10406387241292343 Publication
Researcher Affiliations
- Center for Veterinary Biologics, Animal and Plant Health Inspection Service, USDA, Ames, IA, USA.
- Center for Veterinary Biologics, Animal and Plant Health Inspection Service, USDA, Ames, IA, USA.
MeSH Terms
- Animals
- Horses
- Horse Diseases / virology
- Horse Diseases / diagnosis
- Biological Products / standards
- Parvoviridae Infections / veterinary
- Parvoviridae Infections / virology
- Parvoviridae Infections / diagnosis
- Parvovirus / isolation & purification
- Real-Time Polymerase Chain Reaction / veterinary
- Drug Contamination
- Hepatitis, Viral, Animal / virology
- Hepatitis, Viral, Animal / diagnosis
Conflict of Interest Statement
Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
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