Safeguarding sight

EQUINE recurrent uveitis (ERU), which is also known as moon blindness, affects between 3% and 15% of the equine population, causing blindness in more than half of those affected.

“Uveitis” refers to inflammation of the uveal tract, which is the vascular tissue within the eye, comprising the iris, ciliary body and choroid. Such inflammation can be a one- off event, caused by trauma or corneal ulceration, for example. ERU, however, is specifically characterised by recurrent bouts of uveitis with no obvious cause.

The reasons for this recurrence are poorly understood, but it appears to be the horse’s own immune system that drives the process, targeting and subsequently damaging the tissues within the eye.

Bacterial, viral, parasitic and non-infectious agents have been implicated in is thought to be involved in some cases.