Officials have confirmed the number of Potomac Horse fever (PHF) cases in northern New York has been higher than usual in recent weeks, encouraging owners to vaccinate but noting that a rise in cases is relatively common this time of year.

An article printed in the Aug. 14 edition of the Watertown Daily Times reported there is an "outbreak" of the "life-threatening gastrointestinal disease" Potomac horse fever.

Potomac horse fever (PHF), or equine monocytic ehrlichiosis, is caused by the bacterium Neorickettsia risticii. Clinical signs include fever, mild to severe diarrhea (although some cases have no evidence of diarrhea), laminitis, mild colic, and decreased abdominal sounds. In rare instances affected pregnant mares abort. The disease is treatable if caught in the early stages, but it can be fatal. N. risticii has been has been linked to parasites of freshwater snails that also infect the larvae of mayflies and caddis flies in fresh water. When the infected fly larvae mature into infected adult flies, they can be ingested by horses inadvertently