Although EP can be transmitted through infected ticks, it is more commonly spread by blood and blood-products via sharing needles; syringes; or improperly cleaned and disinfected equipment between infected and uninfected horses. | Photo: Alexandra Beckstett/The Horse

Animal health officials have confirmed nearly two dozen cases of piroplasmosis in Tennessee horses. The state veterinarian’s office is investigating the equine piroplasmosis (EP) outbreak in a group of racing Quarter Horses in Middle Tennessee.

Thus far, 22 horses residing at five locations in Bedford, Rutherford, and Williamson counties have tested positive. All the horses are quarantined and being treated.

EP 101

Equine piroplasmosis is a parasitic infection of equids that can be spread naturally to equids by ticks or, more commonly, by humans to equids through contaminated needles, syringes, and treatment/surgical equipment and products. The causative agents of the disease are protozoan parasites called Theileria equi and Babesia caballi