Equine viral arteritis
Activities in 2009
Equine viral arteritis
Professor Trevor Drew
Veterinary Laboratories Agency - Weybridge
Woodham Lane, New Haw, Addlestone, SurreyKT15 3NB, United Kingdom
Tel.: +44(0)1932 357 637, Fax: +44(0)1932 357 239
Email: bsite:
Summary of general activities related to the disease
1.Test(s) in use/or available for the specified disease at your laboratory
Test / For / QA / Import / Export / Diagnosis / Private / Overseas / TotalSNT
(TC1247) * / Antibody / 12 / 33 / 1516 / 67 / 362 / 325 / 2315
Virus isolation (TC0550) * / Virus / 3 / 2 / 40 / 42 / 0 / 0 / 87
RT-PCR / Viral RNA / 13 / 2 / 40 / 42 / 0 / 0 / 97
*These tests are accredited to ISO17025 under the VLA's United Kingdom Accreditation Service (UKAS) Testing Laboratory 1769 certificate.
Virus isolation is carried out using Rabbit Kidney(RK-13)cell culture, three passages, followed by indirect peroxidase staining for EAV antigen.All the semen samples submitted for investigation were tested by both cell culture and RT-PCR for EAV, and were all found to be negative for both tests.
2.Production and distribution of diagnostic reagents
VLA maintains stocks of diagnostic reagents for EAV which are used for its own tests and are provided externally. For details of supply, contact dard EVA reference antiserum used in the VLA VN-test and cell cultures were supplied to the Romania, Germanyand Israel.
Activities specifically related to the mandate
of OIE Reference Laboratories
3.International harmonisation and standardisation of methods for diagnostic testing or the production and testing of vaccines
VLA Weybridge participated in ring trials with the CRL in France and other countries in the EU, aiming towards harmonisation of the EVA VN-test, and for the single tube RT-PCR and qPCR for EAV.
The VLA results compared well with the other laboratories and the single tube RT-PCR and qPCR was comparable with the cell culture results but the values obtained for the PCRs indicated slightly greater sensitivity.
4.Preparation and supply of international reference standards for diagnostic tests or vaccines
None for 2009
5.Research and development of new procedures for diagnosis and control
The VLA has continued its participation in the network of OIE Reference Laboratories at the Canadian FoodInspection Agency, the Gluck Research Centre Lexington Kentucky and also the CRL in France in PCR procedures, to fine tune the RT-PCR for EAV using different primers on known positive and negative samples, to aid the diagnosis, sequencing and phylogenetics of new virus isolates. VLA is currently developing qPCR tests for the diagnosis of EAV in semen to increase our range of test capabilities.
6.Collection, analysis and dissemination of epizootiological data relevant to international disease control
None for 2009
7.Provision of consultant expertise to OIE or to OIE Members
The OIE Reference Expert provided commentary on revisions to the OIE Chapter in the Manual of Diagnostic Tets and Vaccines, both directly to the OIE and to the UK Government.Advice was also provided to Viet Nam, the OIE and FAO on the related arterivirus, porcine reproductive and respiratory syndrome virus.
8.Provision of scientific and technical training to personnel from other OIE Members
None for 2009
9.Provision of diagnostic testing facilities to other OIE Members
None for 2009
10.Organisation of international scientific meetings on behalf of OIE or other international bodies
None for 2009
11.Participation in international scientific collaborative studies
The VLA participated in an international meeting organised by AFSSA, Maisons Alfort, France in December 2009, on the evaluation and harmonisation of serological and PCR tests for EVA.For the serological tests, all the participants performed the EVA VN-test in their respective laboratories. At the meeting to discuss the results, the source and passage of RK13 cells, virus strain and titres, and the use of complement were discussed with a view to harmonising the test procedures in institutes that perform the test.The ring trials performed for virus isolation and various PCRs for the detection of EAV in semen were also discussed. For the VI the source and passage level of the RK13 cells was discussed.For the PCRs the RNA extraction procedures and target region of the EAV genome for the EAV primers was discussed. A full report of the EVA serology and PCR discussions, and future plans will be published by the organisers of the meeting in due course.
12.Publication and dissemination of information relevant to the work of OIE (including list of scientific publications, internet publishing activities, presentations at international conferences)
Presentations at international conferences and meetings
None for 2009
Scientific publications in peer-reviewed journals
None for 2009
Other communications
None for 2009
13.Inscription of diagnostic kits on the OIE Register
i)Did you participate in expert panels for the validation of candidate kits forinscription on the OIE Register? If yes, for which kits?
None for 2009
ii)Did you submit to the OIE candidate kits for inscriptionon the OIE Register? If yes, for which kits?
None for 2009
Acknowledgements:
The role of VLA Weybridge as an OIE Reference Laboratory for EVA is funded by the UK Department for Environment, Food and Rural Affairs (Defra) under contract SV3300.This report was prepared by Trevor Drew and David Westcott.
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Annual reports of OIE Reference Laboratories and Collaborating Centres, 20091