• Photo by Molly Montag.

AAEP Updates Equine Piroplasmosis Guidelines  

The American Association of Equine Practitioners (AAEP) recently released comprehensive guidelines to assist veterinarians with identification, control and prevention of Equine Piroplasmosis (EP), a blood-borne protozoal infection of equids with a mortality rate for infected horses of up to 50%.

While natural tick-borne transmission of EP in the U.S. is rare, cases have been recognized in recent years specifically involving iatrogenic transmission in Quarter Horse racehorses. Guidelines author Dr. Angela Pelzel-McCluskey, national epidemiologist for equine diseases at USDA APHIS Veterinary Services, said most of these racehorses had direct ties to unsanctioned racing and unhygienic practices by their owners and trainers. 

“Re-use of needles, syringes, and IV sets, blood-contamination of multi-dose drug vials, use of illegal blood products from other countries, and direct blood doping between horses have been identified as common methods of blood-borne disease transmission in this population,” said Dr. Pelzel-McCluskey. “Equine practitioners should be aware of the risk for EP and other blood-borne diseases, such as EIA, in this high-risk population and provide educational outreach to clients on appropriate biosecurity to prevent disease transmission between horses.”  

It is recommended that current Quarter Horse racehorses be routinely tested for EP and EIA during their racing career. Equine practitioners encountering former Quarter Horse racehorses as part of a pre-purchase or routine exam should discuss with owners the risk of previous disease exposure and recommend testing. 

EP is considered a foreign animal disease in the U.S. Any detection must be reported to the state veterinarian and/or to USDA APHIS Veterinary Services. Horses infected with EP can be enrolled in a USDA APHIS-approved EP treatment program, which is often successful at permanently eliminating the infection. 

The EP Guidelines were reviewed and approved by the AAEP’s Infectious Disease Committee and board of directors. View the guidelines or save them to your mobile device for future reference at https://aaep.org/document/aaep-infectious-disease-guidelines-equine-piroplasmosis.

Besides Equine Piroplasmosis, AAEP guidelines for four additional foreign animal diseases are available at https://aaep.org/infectious-disease-control/foreign-animal-disease-guidelines. In addition, 22 equine infectious disease guidelines can be found at https://aaep.org/guidelines/infectious-disease-control/using-guidelines.