How many serotypes are described for African Horse Sickness?

How many serotypes are described for African Horse Sickness?

• A. 4
• B. 7
• C. 9
• D. 12

Answer: (C)

The main idea is that African Horse Sickness virus has multiple antigenically distinct forms, defined by the immune response to its outer capsid protein VP2. Nine serotypes have been described, labeled AHSV-1 through AHSV-9, and they are largely serotype-specific in immunity, meaning antibodies against one serotype don’t reliably neutralize the others. This is why vaccines for African Horse Sickness are typically multivalent, aiming to cover several circulating serotypes. The count 9 reflects the established diversity from immune-typing studies, and other numbers would under- or overestimate the true range of serotypes.

The main idea is that African Horse Sickness virus has multiple antigenically distinct forms, defined by the immune response to its outer capsid protein VP2. Nine serotypes have been described, labeled AHSV-1 through AHSV-9, and they are largely serotype-specific in immunity, meaning antibodies against one serotype don’t reliably neutralize the others. This is why vaccines for African Horse Sickness are typically multivalent, aiming to cover several circulating serotypes. The count 9 reflects the established diversity from immune-typing studies, and other numbers would under- or overestimate the true range of serotypes.