African Horsesickness Viruses (AHSV) refer to a group of viruses that belong to the Orbivirus genus in the Reoviridae family. These viruses primarily infect horses, causing African horse sickness (AHS), a highly contagious and often fatal disease. AHSV is primarily transmitted to equines through the bites of infected Culicoides midges, which act as vectors for the virus.
African Horsesickness Viruses are characterized by their genome, which comprises 10 segments of double-stranded RNA. There are nine serotypes of AHSV identified, namely AHSV-1 to AHSV-9, each varying in their genetic composition and causing distinct clinical manifestations in infected horses. The severity of the disease may also vary depending on the host's breed and immune response.
Clinical signs of African horse sickness caused by AHSV can range from mild to severe, including fever, respiratory distress, edema (especially in the head and neck region), loss of appetite, depression, weight loss, and often culminating in death due to a combination of cardiac and respiratory failure. AHS has a high mortality rate, and surviving horses may suffer long-term health complications, limiting their productivity.
Prevention and control measures for African horse sickness primarily include vaccination, especially in areas where the disease is endemic. Strict quarantine measures and insect control techniques are also crucial in reducing the transmission of AHSV. Due to the considerable impact on the equine population, AHS is considered a notifiable disease, requiring immediate reporting to veterinary authorities for prompt intervention and disease surveillance.
