Disease Alerts

Number Confirmed: 22

Facility Type: Racetracks

Comments: Multi-State Equine Infectious Anemia Outbreak in Quarter Horse Racehorses

On September 20^th and 24^th, the National Veterinary Services Laboratories (NVSL) confirmed equine infectious anemia (EIA)-positive results in 4 Quarter Horse racehorses that were part of a group recently moved from racing in New Mexico to Los Alamitos in California.  Several of the EIA-positive horses were showing clinical signs of EIA upon arrival to California.  Testing of in-contact horses in California and epidemiologically-linked horses in Texas and New Mexico has yielded an additional 18 EIA-positive horses to date. All 22 EIA-positive horses (12 in CA, 2 in NM, 8 in TX) were racing under the same trainer and attending the same series of sanctioned races in New Mexico in August and September. Additional exposed horses have been identified and are in the process of being tested in multiple states.  The current epidemiological investigation indicates that spread of EIA among these horses occurred by iatrogenic transmission. Twenty (20) of the 22 EIA-positive horses have been euthanized, 1 horse remains quarantined in New Mexico, and 1 horse died of the disease. Updates to the current situation will be posted as more information becomes available. Prior Alerts: 4020, 4041, 4042