Seroprevalence and factors associated with seropositivity to equine arteritis virus in Spanish Purebred horses in Spain.
BACKGROUND
Equine viral arteritis (EVA), a disease caused by infection with the equine arteritis virus (EAV), is present in many European countries. In Spain, the last confirmed outbreak was reported in 1992 and there is a paucity of seroprevalence studies. The disease has a major impact on the equine breeding industry, which is mainly represented by Spanish Purebred (SP) horses in Spain.


OBJECTIVE
To estimate the seroprevalence of EAV in the breeding SP horse population in central Spain and identify potential horse and studfarm level factors associated with seropositivity to EAV.


METHODS
Cross-sectional study.


METHODS
Individual serum samples from 555 SP horses, collected between September 2011 and November 2013 at 35 studfarms, were tested using a commercially available EAV antibody ELISA and seroneutralisation as the World Organisation for Animal Health reference confirmation test for samples with positive and equivocal results. Data on factors putatively associated with seropositivity to EAV were collected via a questionnaire and examined using random effects logistic regression for analysis of clustered data.


RESULTS
Equine arteritis virus seroprevalence in the SP breeding population in central Spain standardised for the sex distribution of the reference horse population, was estimated to be 16.8% (95% confidence interval 5.2-28.5%). Increasing numbers of breeding mares on the studfarm and increasing percentage of mares with reproductive problems during the last 12 months were identified as being positively associated with EAV seropositivity. Mares vaccinated against Equine herpesvirus-1 (EHV-1) and/or -4 (EHV-4) were also positively associated with EAV seropositivity.


CONCLUSIONS
These findings are of importance to ensure appropriate biosecurity measures for studfarms are carried out and may help facilitate the development of an EVA surveillance programme in the SP breeding horse population.
VISAVET Health Surveillance Centre, Universidad Complutense, Madrid, Spain.|Departamento de Medicina y Cirugía Animal, Facultad de Veterinaria, Universidad Complutense, Madrid, Spain.
F
http://orcid.org/0000-0002-1142-3944
F
Cruz
Departamento de Medicina y Cirugía Animal, Facultad de Veterinaria, Universidad Complutense, Madrid, Spain.
P
P
Fores
National Institute for Public Health and the Environment (RIVM), Centre for Infectious Disease Control (CIb), Bilthoven, The Netherlands.|Utrecht University, Faculty of Veterinary Medicine, Department of Infectious Diseases and Immunology, Utrecht, The Netherlands.
L
L
Mughini-Gras
Centre for Preventive Medicine, Animal Health Trust, Suffolk, UK.
J
J
Ireland
VISAVET Health Surveillance Centre, Universidad Complutense, Madrid, Spain.|Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad Complutense, Madrid, Spain.
M A
MA
Moreno
Centre for Preventive Medicine, Animal Health Trust, Suffolk, UK.
R
R
Newton
D000818:Animals; D018174:Arterivirus Infections / Q000097:blood / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D007240:Equartevirus / Q000302:isolation & purification*; D005260:Female; D006734:Horse Diseases / Q000097:blood* / Q000453:epidemiology / Q000517:prevention & control / Q000821:virology; D006736:Horses; D008297:Male; D016017:Odds Ratio; D011159:Population Surveillance; D012307:Risk Factors; D016036:Seroepidemiologic Studies; D013030:Spain / Q000453:epidemiology; D014765:Viral Vaccines / Q000276:immunology
D014765:Viral Vaccines
Horse; Spain; equine viral arteritis; risk factors; seroprevalence