According to a report published on Tuesday (March 9), more than 40 horses currently stabled and isolated at Red Shores Racetrack & Casino at the Charlottetown Driving Park have tested positive for the bacteria that causes equine strangles.
Reports from the CBC indicate that 45 horses on the Charlottetown backstretch have been placed in isolation after testing positive for Streptococcus equi, the bacteria that causes strangles. However, none of the nearly 200 horses that were tested have shown signs or symptoms of the sometimes fatal equine disease.
"It just basically means that they've come back as PCR positive, which indicates that the horse has been exposed to Strep equi, and therefore that the potential to infect other horses might be there," Brett Revington, director of racing for the Atlantic Provinces Harness Racing Commission, told the CBC.
The horses in question underwent PCR (polymerase chain reaction) testing, which detects the presence of bacterial DNA. As such, the test does not make a distinction between live and dead bacteria, nor if a horse received a vaccination to protect against strangles. In the interest of equine safety, the horses who tested positive for the Streptococcus equi bacteria have been physically separated from the rest of the Charlottetown horse population.
"All 45 horses, they've been separated within zones, within their barns, generally positive horses at one end, and then a stall in between, and then with the negative horses on the other end," Revington said. "They're being monitored by the attending veterinarian, and the trainers and grooms that work in those barns."
In addition to the isolation of the affected horses, there is another readily available means of flattening the strangles curve: a vaccine with further potential to prevent horses exposed to the Streptococcus equi from contracting strangles, or at least make the symptoms less severe exists — but care must be given that horses vaccinated against strangles have not previously contracted the disease for fear of a strong immune response that could prove detrimental.
"The body's own immune system kind of overreacts, and that causes a severe disease, where you get swelling in the legs and fevers," explained Dr. J. Trenton McClure. "Those are relatively rare but when they do occur, it's because the horse already has a strong immune response."
For the time being, the focus of Red Shores, the APHRC and horsepeople is to contain the outbreak and minimize its effects. Given that racing at Charlottetown is not slated to resume until May, it remains "too early to comment" about the status of the upcoming meet, per Revington.