Press release

Date: 18 April 2007

Outbreak of possible African horse sickness in the Surveillance Zone

in the Western Cape Province

STATEMENT BY COBUS DOWRY, MINISTER OF AGRICULTURE IN THE WESTERN CAPE


HORSE MOVEMENT CONTROL * WESTERN CAPE PROVINCE

On Wednesday, 18 April 2007 a meeting was held at Elsenburg, head office of the Department of Agriculture of the Western Cape Province, to review the disease outbreak, which led to the deaths of 13 horses that died since 15 March 2007 in the Western Cape. The meeting was arranged by the Western Cape Veterinary Services and attended by 20 private veterinarians servicing the horse industry and Professor Allan Guthrie of the Equine Research Centre at the University of Pretoria Faculty of Veterinary Science.

Initial tests performed to establish the cause of these deaths revealed the presence of African Horse Sickness Virus (AHSV) genetic material. The clinical, epidemiological and post mortem findings were not typical of AHS, and further tests have been requested to confirm the diagnosis. From a legal point of view, and in consideration of the export approval for horses to Europe, movement controls for horses were however instituted to prevent the spread of possible AHS.

Preliminary results communicated by the Onderstepoort Veterinary Institute (OVI) on 18 April 2007 also revealed the presence of Equine Encephalosis Virus (EEV) in tissues collected from some of the dead horses, as well as from blood samples from ill horses. Although generally not regarded as a serious disease, this particular strain of EEV (Serotype 1 Bryanston) isolated in the Western Cape seems to be more pathogenic in certain individual susceptible animals, as evidenced by the recorded mortalities.

According to the large number (many hundreds) of fever reactions and mild disease in horses reported by private equine veterinarians in the Western Cape, the distribution of this virus may already be widespread in the AHS Surveillance Zone and some areas in the AHS Protection Zone.

Further laboratory results are awaited to establish whether the African Horse Sickness positive tests resulted from vaccine virus or from infection. A mixed infection of EEV and AHS is not ruled out at this stage.

Due to these findings the Department of Agriculture of the Western Cape decided, in collaboration with the National Department of Agriculture, to maintain the ban on the  movement of horses into, through or within the AHS Surveillance Zone and AHS Free Area.

The apparent cessation of mortalities in horses, indicating an imminent clinical endpoint of this outbreak, has allowed Veterinary Services to be more flexible. As a result of this, and based on the relative risks involved, consideration will be given to allow certain movements under cover of  State Veterinary Movement Permits (Red Cross Permits). Such movements will be subject to strict disease prevention precautions as prescribed by the issuing State Veterinarian.

Racehorses will be allowed to move to the Western Cape racetracks as described above, but will only be allowed to move from two hours after sunrise to two hours before sunset. They will also not be allowed to overnight at the racetracks.

Movements to other parts of the Western Cape and to the other provinces will also be considered, depending on the approval of the receiving parties at destination. Even though Equine Encephalosis had been detected in most parts of South Africa in the past, precautions must still be taken when bringing many horses together, as the Bryanston strain of Encephalosis is capable of killing significant numbers of horses acutely.

Information regarding the issuing of permits can be obtained from Drs Gary Bührmann and Ronald Sinclair from the Western Cape Department of Agriculture.
 

Enquiries: Alie van Jaarsveld 084 604 6701

Drs Gary Bührmann and Ronald Sinclair (Western Cape Department of Agriculture)
Telephone: (021) 808 5253 Fax: (021) 808 5125

Alie van Jaarsveld Spokesperson Ministry of Agriculture: Western Cape
Tel: (021) 483 4930 Fax: (021) 483 3890 Cell: 084 604 6701 E-mail: avjaarsv@pgwc.gov.za