# Equine Parvovirus-Hepatitis Population Dynamics in a Single Horse over 16 Years

## TL;DR

This paper studies how a new virus, equine parvovirus-hepatitis, evolved in a single horse over 16 years through genetic changes.

## Contribution

The study provides the first detailed timeline of capsid gene evolution in a single animal infected with equine parvovirus-hepatitis.

## Key findings

- EqPV-H infection in a horse led to a sequence variant bottleneck followed by complex viral population dynamics.
- High-throughput sequencing revealed patterns of emergence, dominance, and replacement of viral variants over 16 years.
- The hypervariable capsid gene region enabled tracking of viral evolution in the host.

## Abstract

Many viruses mutate rapidly to adapt to host defenses, and for some of these viruses, the result is long-term infection in individual hosts. The work described here examines the infection and long-term maintenance of a newly identified virus, equine parvovirus-hepatitis (EqPV-H), in an individual horse. This description is possible because of a hypervariable region in the capsid gene; sequence variants were tracked by high-throughput sequencing of serum samples taken over a 16-year period. The data support the hypothesis that EqPV-H infection resulted in a sequence variant bottleneck. The continuing infection evolved into a complex viral population showing a pattern of emergence, dominance, and recession with replacement. This is the first temporal description of the capsid gene evolution of EqPV-H in a single animal.