Equine Piroplasmosis
On October 20, 2009, the Texas Animal Health Commission announced that a Texas horse exhibiting clinical signs of illness had been diagnosed with Equine Piroplasmosis (EP). The investigation is continuing and 370 horses have tested positive for Theileria equi (formerly known as Babesia equi). Of the 370 EP positive horses, 289 are located on the index premises with 54 located on other premises in Texas. Horses moved from the index ranch since 2004 are being traced to other states and, to date, there have been 28 positive horses detected in 13 additional states.
Ten horses from the index premises in Texas, which traveled into Florida before the outbreak was discovered, have been located, quarantined and tested. All horses located on the same premises as the trace horses were tested for EP as well. Five of the ten horses traced from Texas tested positive for T. equi while all the cohort horses tested negative. Currently, none of the five positive horses traced from Texas remain in Florida.
EP is considered a foreign animal disease, not endemic to the United States. It is a blood-borne parasitic disease primarily transmitted between horses by ticks or contaminated needles and is not directly contagious from one horse to another. The two protozoan parasites that infect the red blood cells of horses and cause EP are Babesia caballi and Thileria equi. Ticks are the natural method of transmission of the EP organisms and the tick species known to be efficient at transmitting EP are not believed to be in Florida.
Acutely affected horses can have depression, fever, anemia (decreased red blood cells) jaundiced (yellow) mucous membranes, and low platelet counts and can die from the disease. In its milder form, EP can also cause horses to have roughened hair coats, constipation, colic, generalized weakness, and lack of appetite. Some horses become chronic carriers of the disease showing little clinical signs but having the ability to transmit the disease to other horses via ticks.
Treatment of infected horses has not been shown to be effective in eliminating the organism (Theileria equi) and infected horses must remain under quarantine.
Requirements for Horses Originating from EP Endemic Areas Entering Florida
In addition to those import regulations set forth in Florida Administrative Code, 5C-3, the Florida Department of Agriculture and Consumer Services, Division of Animal Industry has placed restrictions on horses originating from EP endemic areas. Currently the State Veterinarian has declared all counties in the state of Texas endemic for EP. These additional requirements are justified to prevent the introduction and spread of this dangerous and transmissible disease. The establishment of Equine Piroplasmosis and associated vector ticks would seriously threaten the horses and equine industry of Florida which produces goods and services of over $3.0 billion per year.
Equine Piroplasmosis Emergency Rule-Requirements for EP Endemic Areas
Areas Declared Endemic for EP
The State Veterinarian has declared that all counties in the state of Texas are currently endemic for EP and as such are subject to emergency rule 5C-ER10-1.
Florida EP Status
There are no positive trace horses currently in Florida.
Movement of Florida Horses to Other States
Due to the EP outbreak many states are implementing additional requirements on Texas horses and some states have included those restrictions on any state with EP positive horses. Therefore, the Florida State Veterinarians Office recommends that anyone traveling out of state with their horse, call the state of destination to ensure there are no additional requirements enacted associated with this outbreak.
