Western Cape on horse movement control
18 April 2007
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
Buhrmann and Ronald Sinclair from the Western Cape Department of
Agriculture.
Enquiries:
Alie van Jaarsveld
Spokesperson
Tel: (021) 483 4930
Fax: (021) 483 3890
Cell: 084 604 6701
E-mail: avjaarsv@pgwc.gov.za
Drs Gary B�hrmann and Ronald Sinclair
Western Cape Department of Agriculture
Tel: (021) 808 5253
Fax: (021) 808 5125
Issued by: Department of Agriculture, Western Cape Provincial
Government
18 April 2007
