Abstract
AIM: To summarise investigation and laboratory data collected between 2001 and 2011 to provide evidence that equine arteritis virus is not present in the horse population of New Zealand.
METHODS: Analysis was carried out on results from laboratory tests carried out at the Ministry for Primary Industries Animal Health Laboratory (AHL) for equine arteritis virus from horses tested prior to being imported or exported, testing of stallions as part of the New Zealand equine viral arteritis (EVA) control scheme and testing as part of transboundary animal disease (TAD) investigations for exclusion of EVA. Horse breeds were categorised as Thoroughbred, Standardbred or other.
RESULTS: A total of 7,157 EVA serological test records (from import and export testing, EVA control scheme testing and TAD investigations) were available for analysis between 2005 and 2011. For the three breed categories a seroprevalence of ≤1.6% at the 95% confidence level was determined for each category. Between 2001 and 2011, as part of the EVA control scheme, the EVA status of 465 stallions was determined to be negative. During 2005–2011 EVA was excluded from 84 TAD investigations.
CONCLUSIONS: There was no evidence of equine arteritis virus being present in the general horse population outside of carrier stallions managed under the EVA control scheme.
CLINICAL RELEVANCE: Equine arteritis virus is absent from the general horse population of New Zealand.
Acknowledgements
The authors would like to thank past and present laboratory technical staff at the Animal Health Laboratory (AHL) for carrying out the rigorous testing, Gary Horner for test development, and Susan Cork, Wlodek Stanislawek, Kok-mun Tham, Jianning Wang, Richard Clough, David Pulford and Grant Munro for test supervision; members of the Animals and Marine Surveillance and Investigation Team and the large number of Ministry for Primary Industry staff, New Zealand Equine Health Association committee members and private veterinarians who have been committed to gaining EVA freedom over the last three decades; and Matthew McFadden for critically reviewing the manuscript. All funding for the project was provided as a part of investigation of transboundary animal disease carried out by the AHL.