Theileria equi is an obligate intracellular tick-borne protozoan parasite which causes equine piroplasmosis in horses. It is found throughout tropical and subtropical regions and areas which high populations of ticks of the family Ixodidae. Ticks act as biological vectors and transport the virus to horses.
T. equi sporozoites invade leukocytes and erythrocytes where it undergoes asexual reproduction.
