Equine parvovirus-hepatitis is detected in South America, Brazil.

This study identifies for the first time the presence of equine parvovirus-hepatitis (EqPV-H) in horses in Brazil, with 12.5% of horses tested showing infection. The researchers find a low genetic variability in the virus with nucleotide identity higher than 94% in comparison with previous isolates.

Methodology

• The research was derived from a retrospective study carried out from 2013-2016, targeting a total of 96 Brazilian horses. These horses were classified based on their previous infection status, either known to be positive for one or more horse “hepatitis viruses” (equine hepacivirus, equine pegivirus-EPgV, and Theiler’s disease-associated virus) or known to be negative.
• The testing process involved the use of a nested PCR specific for EqPV-H. It allowed identifying the presence of the virus in the horse samples.

Findings

• The testing revealed that EqPV-H DNA was present in 12.5% (12/96) of the horses from 46.6% (7/15) of the farms evaluated.
• There was a similar rate of the virus found between the coinfected group (12.3%, 7/57) and the non-coinfected group (12.8%, 5/39). Coinfection with EPgV was most common, accounting for 5 out of 7 instances.
• Notably, despite the presence of the virus, majority of the horses had no overt clinical or laboratory signs of infection. However, altered serum biochemical parameters showed potential subclinical liver disease in some animals (3/12).

Conclusion

• The study demonstrates, for the first time in South America, the circulation of EqPV-H in horses. The Brazilian strains of EqPV-H showed low genetic variability, indicating a high genetic similarity (higher than 94%) with prior isolates.
• This discovery has important implications for understanding the geographical spread and host adaptation of the virus. Further studies are required to understand the full breadth of EqPV-H’s distribution and potential impact on horse health in South America.