It is a protozoal infection which is spread in feces and normally inhabits possums. It travels through a horse and settles out sometimes in the spinal cord or even the brain where it causes damage. Treatment is expensive and often some degree of damage is permanent. Unfortunately they can also get reinfected. .
It is a disease caused by a bacteria that affects a horses central nervous system
Possums are a huge carrier of this where I’m from
It's an American disease that's caused by spore contaminated water or food. It attacks the nerve system. It causes weakness and muscle wastage, sweating and slow reflexes if its in the spinal cord. It rarely reaches the brain, but when it does is can cause head tilting and facial paralysis, as well as seizures and behavioural issues. It can kill a horse if left untreated. Majority of horses improve with treatment but most do not completely recover and relapses are common.