The Tennessee Department of Agriculture has identified a case of Potomac horse fever (PHF) in a horse located in Washington County. At this time, no further details have been released.
EDCC Health Watch is a marketing program from Equine Network that utilizes information provided by the Equine Disease Communication Center (EDCC) to create and distribute verified equine disease reports. The EDCC is an independent nonprofit organization that relies on industry donations to offer accessible infectious disease information.
About Potomac Horse Fever
Potomac horse fever is caused by Neorickettsia risticii, a microorganism found in parasites known as flukes (flatworms) that infect aquatic snails and insects. Horses can contract Potomac horse fever by ingesting insects carrying the organism or by consuming water contaminated with N. risticii. Moreover, horses can become infected with Potomac horse fever by accidentally ingesting contaminated insects or parasites present in their feed, water, or pasture.
The incubation period for Potomac horse fever ranges from one to three weeks, and the mortality rate can be as high as 30%. Although vaccines for Potomac horse fever are not completely effective, vaccinated horses typically exhibit fewer and less severe symptoms.
Most cases of Potomac horse fever are reported between July and September, with outbreaks occurring seasonally.
Horse owners and caregivers, particularly those with horses near bodies of water like creeks and rivers, should be vigilant for symptoms such as:
- Diarrhea
- Colic
- Loss of appetite
- Lethargy
- Toxic shock
- Dehydration
- Abortion in pregnant mares
- Laminitis
- Mild to severe fever.