Borna Disease

The sudden death of Diallo BB, a top grand prix dressage horse owned by German Olympian Jessica von Bredow-Werndl, has drawn attention to equine Borna disease virus, though the virus was later ruled out as the cause. The 11-year-old Hanoverian gelding's illness remains unexplained, prompting interest in the rare neurotropic virus primarily affecting Central Europe. With fatality rates of 80 to 100 percent in horses, the disease underscores ongoing veterinary challenges.