The Associated Press today (Oct. 8) reported that 54 quarantined horses are being removed from the Hoosier Park racetrack in central Indiana after two other horses tested positive for Streptococcus equi (the bacterium that causes the disease strangles). On Oct. 1 Hoosier Park Racing & Casino detected two horses in the quarantine barn exhibiting fever, so as a precautionary measure, both horses were removed from the grounds and shipped to a secondary quarantine facility per recommendation of the Indiana State Board of Animal Health.
Hoosier Park officials had placed the 54 horses in quarantine at the racetrack on Sept. 12 after one Thoroughbred at the stable began exhibiting signs of equine strangles, a bacterial disease common in horses that can be life-threatening.
Racing manager Jeffrey Smith was reported in the AP article to have said the disease doesn't appear to have spread to any of the track's other 16 barns, where about 1,000 horses are housed.
For more information on the outbreak read "Two Febrile Horses Removed from Hoosier Park Quarantine."
One horse at the racetrack died in September, but that horse was found to be negative for strangles and positive for colitis. See "Early Hoosier Park Strangles Tests Negative, Horse Dies of Colitis" for more information.
Disclaimer: Seek the advice of a qualified veterinarian before proceeding with any diagnosis, treatment, or therapy.