California Department of Food and Agriculture (CDFA), Animal Health Branch (AHB), veterinarians are currently investigating infections of Equine Infectious Anemia (EIA) and Equine Piroplasmosis (EP) (Babesia equi) in racing Quarter Horses. The investigation began in July 2012, following confirmation of EIA in a racing Quarter Horse initially sampled to meet California Horse Racing Board entry requirements. The owner acknowledged sharing needles between horses. The testing of exposed horses on the premises led to subsequent confirmation of EIA in a second horse; sixteen other exposed horses were test negative for EIA.
California regulation requires retesting of exposed horses sixty (60) days. To date, ten (10) of the sixteen (16) exposed horses have been retested. Two (2) of the ten (10) were confirmed positive for EIA and EP; one (1) of these dual-infected horses was euthanized. AHB veterinarians sampled thirty-three (33) additional exposed horses, which had a history of direct exposure to the two most recently diagnosed positive cases. Of the thirty-three (33) exposed horses, one (1) tested positive for EIA and five (5) tested positive for EP; one (1) EIA positive horse was euthanized. One (1) dual-infected horse and the five (5) EP positive horses remain under quarantine and isolation. Thirty-two (32) exposed horses, which are test negative, remain under quarantine and will be retested for EP and EIA in 60 days.
The epidemiologic investigation indicates transmission of the EIA and EP organisms is most likely attributed to poor biosecurity practices – specifically, the sharing of needles. The population of racing Quarter Horses involved in this investigation is considered high-risk for disease transmission due to their potential participation in unsanctioned racing.
At the time of retest, California Animal Health Officials were unable to locate six (6) of the horses exposed to the EIA-positive horses detected in July 2012. The missing racing Quarter Horses are: Fruitstand Freckles (3 year old chestnut filly, no lip tattoo), Jazzy Patriots (5 year old Bay mare, lip tattoo 1042Z), Hells Bells Hawk (4 year old mare, lip tattoo 10936), and AShot of Fury (2 year old bay colt, lip tattoo 12157). Additionally, The Doll (3 year old Thoroughbred filly, no lip tattoo), remains missing. The last known location of these six (6) horses was Turlock, California. Anyone with information on the location of these horses or knowledge of these horses is asked to contact Dr. Katie Flynn at [email protected] or 916-900-5039.