I've just returned from Saratoga Springs, New York, where several people mentioned to me that there is or was an outbreak of Potomac Horse Fever (PHF)in the region. This was news to stop me in my tracks.
At one farm that I visited in Ballston Spa, I was told that one of the horses there had recovered from PHF-like symptoms.
An announcement from Saratoga Equine Clinic has been posted to help put horse owners in upstate New York both on the alert and at ease. There does seem to be a problem with sick horses in the area, and the horses need medical attention, but it might be less severe than the horrors of true Potomac Horse Fever.
Any illness is disturbing and this one comes at a time when horses are at their most mobile. The Northway was lined with horse vans bringing horses to the racetrack at Saratoga after Belmont Park's closing on Monday. Polo activity is accelerating. The County Fair was in full swing in Ballston Spa, with horses coming and going daily. And horse owners were out enjoying their horses on a perfect summer weekend.
Saratoga Equine reports that so far, no horses to their knowledge have died from the unknown illness. They remarked in their announcement, "Although the prevailing clinical signs are very typical of PHF (Potomac Horse Fever), diagnostic testing to confirm a PHF infection has been unrewarding."
The vets there are crediting vaccination with helping many horses in the area: "Although the efficacy of PHF vaccines in preventing clinical disease is very controversial, our clinical observation is that vaccinated horses have a better chance surviving the disease. Therefore, non-PHF-vaccinated horses should receive immunization."
Principle symptoms of PHF are general lethargy and fever, sometimes accompanied by colic-like symptoms, diarrhea and other alarming medical signs that may look like other diseases. If left untreated,the disease may escalate into a true medical emergency. Many severe cases have included disastrous laminitis as a side effect.
In Texas, three cases of Potomac Horse Fever, which is not a regulatory disease, have been confirmed in Kerr County by the Texas Veterinary Medical Diagnostic Laboratory. Potomac Horse Fever is not typically found in Texas, but the recent flooding there is being blamed for the cases.
Horses with PHF usually live near rivers, streams, ponds or canals. The infection involves tiny flukes that are parasites of water snails. The flukes hatch their offspring into the water, and these are then picked up by aquatic insects that molt into flying insects, including caddis flies and mayflies.
Horses can become exposed to Potomac Horse Fever when they eat or drink anything contaminated with the insects.
I'll keep you posted on this story; thanks to Saratoga Equine Clinic for keeping the horse world informed.