All horses competing at the American Quarter Horse Association (AQHA) World Show will now be required to test negative for the tick-borne disease equine piroplasmosis (EP) before being allowed to enter the show grounds. The mandate comes following a February 2011 recommendation from Tom Persechino, AQHA executive director of competition and breed integrity, and Ward Stutz, AQHA competition and breed integrity staff member.

In a memorandum to the AQHA Executive Committee, Persechino and Stutz explained, "We believe that requiring testing at AQHA World Shows is prudent and responsible. … These are inexpensive tests that we don’t believe will burden our members.

"Currently, (race) tracks from 11 different states have testing requirements for equine piroplasmosis and that number will increase," the memorandum continued. "With the potential of an infected racehorse retiring to the show pen, the show industry is vulnerable. As the industry leader, AQHA needs to be vigilant and establish testing requirements to ensure any case of equine piroplasmosis can’t be traced back to an AQHA event."

The causative agents of equine piroplasmosis are Babesia caballi and B. (Theileria) equi. Equine piroplasmosis is spread through the transfer of blood–either by certain species of ticks or the reuse of needles, syringes, and other blood-contaminated equipment that has not been sanitized between uses