African Horse Sickness

African horse sickness (AHS) is an insect-borne disease affecting horses and related species such as mules, donkeys, and zebras. Horses are most severely affected by the disease. AHS is caused by the AHS virus, of which there are nine different strains. Any of the strains can cause disease with severity ranging from a mild fever to sudden death. AHS causes fever and impairment of the respiratory and/or circulatory systems. The sickness can have a sudden onset and is highly fatal.

In Canada, African horse sickness is a reportable disease under the Health of Animals Act, and all cases must be reported to the Canadian Food Inspection Agency (CFIA).

What information is available?

• Countries recognized as free from the disease
• Fact Sheet