Investigation of Three Newly Identified Equine Parvoviruses in Blood and Nasal Fluid Samples of Clinically Healthy Horses and Horses with Acute Onset of Respiratory Disease

Abstract

Three newly identified equine parvoviruses (equine parvovirus hepatitis (EqPV-H), equine parvovirus CSF (EqPV-CSF) and equine copivirus (Eqcopivirus)) have recently been discovered in horses with respiratory signs. However, the clinical impact of these three equine parvoviruses has yet to be determined. Nasal fluid samples and blood from 667 equids with acute onset of fever and respiratory signs submitted to a diagnostic laboratory were analyzed for the presence of common equine respiratory pathogens (equine influenza virus, equine herpesvirus-1/-4, equine rhinitis A and B virus, S. equi subspecies equi) as well as EqPV-H, EqPV-CSF and Eqcopivirus by qPCR. An additional 87 clinically healthy horses served as controls. One hundred and seventeen sick horses tested qPCR-positive for at least one of the three parvoviruses. Co-infections with common respiratory pathogens and parvoviruses were seen in 39 sick equids. All 87 clinically healthy horses tested qPCR-negative for all tested common respiratory pathogens and 10 healthy horses tested qPCR-positive for one of the equine parvoviruses. When the frequency of detection for EqPV-H, EqPV-CSF and Eqcopivirus of equids with respiratory signs was compared to that of clinically healthy horses, the difference was not statistically significant (p > 0.05), suggesting that the three recently identified equine parvoviruses do not contribute to the clinical picture of equids with respiratory disease.

Investigation of the Role of Healthy and Sick Equids in the COVID-19 Pandemic through Serological and Molecular Testing

“…Demographic and clinical information from horses with acute onset of fever and respiratory signs was previously reported [ 10 ]. Briefly, the population ranged in age from 1 month to 34 years (median 9 years), with greater numbers of males (61%) compared to females (39%).…”

“…Nasal fluid samples from 667 equids with acute onset of upper airway infection were enrolled in the study. The same samples were used to investigate three newly identified equine parvoviruses in a recent study [ 10 ]. The respiratory secretions were submitted to a commercial diagnostic laboratory from 1 January 2020 to 31 December 2020 for the molecular detection of common respiratory pathogens, including equine influenza virus (EIV), equine herpesvirus-1/-4 (EHV-1/-4), equine rhinitis A and B virus (ERVs) and Streptococcus equi subspecies equi ( S. equi ).…”

“…Nasal fluid samples from 667 horses with acute onset of fever and respiratory signs were tested for the presence of EIV, EHV-1/-4, ERVs and S. equi as previously reported [ 10 , 12 , 13 ]. Primers and probes targeting the S gene of SARS-CoV-2 were designed following BLAST analysis of published sequences from GenBank ( , accessed on 1 March 2020) ( Table 1 ).…”

Virus Infection in Equine

“…Several such viruses were recently found in horses, by either serology or by PCR, but their clinical significance is yet unknown. These include Equine Corona virus (ECoV) [28], Equine Parvoviruses [29], Equine Herpes virus-2, 5 [27] and Equine Encephalosis virus [12], which are described in this special issue.…”

“…Pusterla et al have tested the molecular prevalence of three Parvoviruses in blood and respiratory secretions of sick and healthy horses in the USA. Equine Parvoviruses were detected in both sick and healthy horses in similar frequencies suggesting that their role in equine respiratory disease is limited and should be further explored [29].…”