African Horse Sickness (AHS) is endemic to most of South Africa, an AHS infected zone, with the exception of part of the Western Cape Province. AHS outbreaks are expected to occur in the infected zone between November and May, often with a peak from February to April, depending on rainfall and temperature. Certain parts of the Western Cape Province have been legislated as AHS controlled areas in terms of the Animal Diseases Act 1984 (Act no. 35 of 1984) and these areas are generally free of AHS.

Outbreaks of AHS in Gauteng and Mpumalanga were officially reported to the Department of Agriculture, Forestry and Fisheries (DAFF) in February and March, however, there is currently no conclusive information indicative of unusually high incidences of AHS outbreaks for this time of the year. There have been no reports of AHS from the AHS controlled area of the Western Cape Province.

Restrictions on equine movements within the AHS infected zone are not routinely implemented by state veterinary services. It would be extremely difficult to implement such controls which would be seen as unnecessarily restrictive by most of the affected horse owners. Since the disease is vectored by biting culicoides midges, restricting horse movements is less effective in the control of the disease.

DAFF is working with the equine industry to establish protective measures for horses in the AHS infected zone. The aim is to reduce the severity of the AHS outbreaks, without imposing onerous restrictions on the movement and trade of equids, within the AHS zone, or placing too great an administrative and financial burden on those involved.

Horse owners are advised to contact their local state veterinarians to find out whether local movement restrictions have been implemented. It is vital (and mandated by law) to report cases of AHS to the state veterinarian so that the department can make informed decisions.

The Animal Diseases Act 1984 (Act no. 35 of 1984) requires owners and managers of animals to take all reasonable steps to protect their animals and to prevent the spreading of diseases from their animals. The movement of equids infected with the AHS virus may increase the risk of AHS infection to other equids and should therefore be limited.

Always consult your private veterinarian who will help tailor informed strategies to protect animals from AHS. Some steps to protect horses from contracting AHS are listed below.

  • Report any case of AHS, or suspected case of AHS, to the local state veterinarian immediately.
  • Limit the populations of biting culicoid midges that vector the AHS virus by considering the following:
    • Culicoid midges gather and breed in moist or muddy areas; eliminate likely breeding areas by draining, and drying out, pools or puddles of standing water.
    • Fix leaking taps and water troughs to prevent the build-up of wet muddy areas
    • Site muck heaps away from the horses (donkeys or mules)
  • Do not let horses out of their stables until the dew on the grass is dry and exclude wet or marshy land from grazing, if possible.
  • Stable horses from at least two hours before sunset to at least two hours after sunrise.
  • Treat horses and stables with a culicoides midge repellent and/or insecticide registered in terms of the Fertilisers, Farm Feeds, Agricultural Remedies and Stock Remedies Act 1947 (Act no. 36 of 1947). In addition, consider the use of fly sheets to help protect horses from midges.
  • Vaccinate horses against AHS with a vaccine registered in terms of the Fertilisers, Farm Feeds, Agricultural Remedies and Stock Remedies Act 1947 (Act no. 36 of 47). Ensure that your animals are vaccinated by the correct person, at the right time, and according to the AHS zone they are in. Now, while there is increased vector activity, is not the right time to vaccinate. Always handle, store and administer vaccines carefully according to the manufacturer’s instructions and ensure that it is kept cold until it is used on the animal. Go to the DAFF website for more information on vaccination against AHS.
  • According to Section 11 of the Animal Diseases Act 1984 (Act no. 35 of 1984), if you have had a case of AHS on your property you should inform your neighbours, anyone who brings equines onto your property and anyone you take one of your horses to. This will help ensure they can take precautions to keep their animals safe too.
  • Please contact your local animal health technician or state veterinarian if you are unsure what AHS zone your animals are in, or if you require any guidance with regards to AHS control measures or reporting. Click here for contact details for the provincial veterinary services and your local state veterinarian.Press release