According to Donnasue Graesser, Wobbly Hedgehog Syndrome (WHS) is a progressive paralysis that occurs in approximately 10% of pet African hedgehogs in North America. Clinical signs of WHS begin with mild ataxia, progress to more severe neurologic signs, and ultimately lead to complete paralysis. The onset of WHS commonly occurs under 2 years of age, but can occur at any age. Progression rate is variable, and the majority of hedgehogs are completely paralyzed by 15 months after the onset of clinical signs. WHS can only be definitively diagnosed by post-mortem examination of tissues from the central nervous system. The characteristic histopathology of WHS is vacuolization of the white matter of the brain and spinal cord, and associated neurogenic muscle atrophy. There is no inflammation of the central nervous system associated with WHS. The etiology of WHS is unknown, but pedigree analysis indicates a familial tendency to the disease.