The longer the worm stays in the eye, the more the eye becomes clouded, eventually leading to total blindness. | Photo: iStock

Warning. This article isn’t for faint-of-heart horse people.

It’s a tale of wriggling worm tails … in horses’ eyeballs. No, not a horror story. This is a true case of parasitic worms living in horses’ eyes, swimming around in a clouded cornea and often visible from the outside. Measuring more than a centimeter in length (and sometimes up to 5 or 6) as adults, they trigger immune responses that lead to total blindness in horses.

Fortunately, however, if caught early, removal of the worm followed by corticosteroid treatment restores the eye back to full health, said SungShik Shin, DVM, PhD, a professor in the division of parasitology at Chonnam National University’s College of Veterinary Medicine, in Gwangju, South Korea