African Horse Sickness Outbreak in South Africa

South African horse owners and veterinarians are managing an outbreak of African horse sickness (AHS) in the George area, which is in southern South Africa (in the southeast region of the Western Cape). As of Feb. 28, 13 horses had died. Current outbreaks are not expected to affect the predicted removal of a European Union export ban on South African horses, as the outbreaks are at least 400 km (almost 250 miles) away from the country's "AHS-free zone," which is the metropolitan area of Cape Town at the southwestern tip of the nation.


African horse sickness (AHS) is a fatal viral disease that can affect horses, mules, and donkeys. Horses are most susceptible to AHS, with a 75-90% mortality rate. The clinical signs of one AHS form include swelling around the eyes, neck, shoulders, thorax, and intermandibular space. Learn more about AHS here:

African horse sickness is spread by Culicoides midges. Affected animals can show clinical signs ranging from pulmonary distress to heart failure, and the disease is often fatal. Owners are encouraged to vaccinate their horses against the disease. Currently, AHS is contained to its namesake continent, where nine serotypes of the disease circulate. (For more information on AHS, visit

Dr. Dempsey de Lange, chief state veterinarian in George, told the Cape Times that the current count could be higher because some horse owners might not have reported deaths (click here to read the article). The first cases were reported in the George area in December 2005. George is near the coast in southeastern South Africa, and it is halfway between Cape Town and Port Elizabeth. The Cape Times reported that de Lange said, "once a midge had bitten a horse it might take a week for symptoms to appear as the virus multiplied in the body."

The George area hasn't experienced an AHS outbreak like this in nearly half a century. Many horses have been treated and have recovered in the outbreak, and others have recovered spontaneously. Quarantine measures have not been implemented, the Cape Times reported.

Dr. James Kitching, deputy director of the Western Cape Department of Agriculture's veterinary laboratory, told The Horse, "Due to good rains in the infected zone (outside the Western Cape) during this summer (mid-October to mid-February), conditions are more favorable for the vectors, and we have the impression that more cases have occurred in the fringes of the infected zone. However, this is an impression and has not been confirmed."

South Africa has an AHS-control zone that covers the Western Cape, with three subzones--an AHS-free zone, a surveillance zone, and a protection zone. When cases were detected in the surveillance zone in 2004, the European Union banned horses from South Africa. Reports have suggested the EU might be lifting the ban within the month, thus reopening the AHS-free zone for export of horses to the EU.

The South African Equestrian Federation encourages horse owners to report all suspected cases to the African Horse Sickness Trust 24-hour helpline at 0861 114 735.

About the Author

Stephanie L. Church, Editor-in-Chief

Stephanie L. Church, Editor-in-Chief, received a B.A. in Journalism and Equestrian Studies from Averett College in Danville, Virginia. A Pony Club and 4-H graduate, her background is in eventing, and she is schooling her recently retired Thoroughbred racehorse, Happy, toward a career in that discipline. She also enjoys traveling, photography, cycling, and cooking in her free time.

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