Potomac Horse Fever, Is Your Horse at Risk?

Potomac horse fever (PHF) causes fever, colic, colitis and diarrhea, and can lead to life-threatening dehydration. Forty percent of horses stricken with PHF also develop laminitis.

Horses living near creeks and rivers are more likely to develop the disease, which is caused when horses ingest infected aquatic insects such as damselflies, caddisflies or mayflies while grazing or drinking.

PHF outbreaks are most often seen in July, August and September when the temperatures increase. The disease cannot be transmitted from horse to horse. The fatality rate in untreated horses is 30 percent. A vaccination for Potomac horse fever is available, although it effectiveness is questionable.

Is your horse at risk for Potomac horse fever? If in doubt, talk to your vet about the disease level of PHF in your area.