Background
Horses from Saudi Arabia, and all countries affected with African Horse Sickness (AHS), must be quarantined for sixty days under import rules of the U.S. Department of Agriculture (USDA) before entering the U.S. Horses from non-AHS countries may be admitted with a shorter quarantine period. The extended period is required to ensure that horses from AHS countries are not infected with AHS, which has a long incubation period.
AHS is a highly contagious and deadly disease that affects horses, donkeys, and mules and has a mortality rate of up to 95% in naive horse populations like that in the U.S.
On March 30, 2015, USDA announced that Saudi Arabia was AHS-free and that horses from that country would no longer have to undergo a sixty day quarantine period. The rule change was effective immediately.