||TAHC Update: Equine Piroplasmosis Disease
(Austin, Texas - Wednesday,
November 4, 2009) - Canada and a number of U.S. states have imposed
movement restrictions or additional entry requirements for horses from
Texas after equine piroplasmosis, a tick-transmitted blood disease of
equine animals, such as horses, donkeys, mules and zebras, was detected
in South Texas in mid-October. Equine piroplasmosis may be carried and
transmitted by as many as 15 species of ticks. Although ticks have been
collected from the South Texas ranch for testing, final results are not
complete, and it is not known whether any of the ticks can serve as a
host for the disease.
“Before moving horses from Texas, we urge you and your veterinarian
to check with animal health officials for any state of destination, to
ensure the animals have met all entry requirements,” said Dr. Bob
Hillman, Texas’ state veterinarian and head of the Texas Animal
Health Commission (TAHC), the state’s livestock and poultry health
regulatory agency. “Regulatory requirements can be fluid as disease
situations evolve, so it is essential to call each state each time you
haul.” As states provide entry restrictions and requirements, the
documents are posted on the TAHC web site at http://www.tahc.state.tx.us.
Dr. Hillman urged equine owners and veterinarians to call state animal
health officials directly before hauling, as many states have not yet
distributed entry requirement information. Contact information for state
veterinarians may be obtained from the TAHC at 800-550-8242, ext. 710,
or by emailing firstname.lastname@example.org.
“We are continuing the equine piroplasmosis disease investigation
initiated in October in South Texas. No horse movement is being allowed
from or to the ranch where the infection was detected,” said Dr.
Hillman. “While this tick-borne disease has not been considered
endemic in the U.S., cases of the disease, scientifically known as Theileria
equi, and previously called Babesia equi, have been detected in the U.S.
Our epidemiologists are tracing the movement of specific equine animals.
Blood tests will be conducted, and the animals will be examined for ticks.
Individual equine owners will be contacted, if their horse needs to be
tested by animal health officials.”
Dr. Hillman refrained from speculating on how many equine animals will
be tested or how many may be exposed or infected. “Until the epidemiological
work and testing of potentially exposed horses is completed, there is
no way to predict how many horses may be affected with this tick-borne
illness,” he said.
Dr. Hillman said horses infected with equine piroplasmosis may appear
well, while others may exhibit a host of non-specific clinical signs,
such as fever or anemia. These clinical signs also could be attributed
to a variety of other diseases or causes. Blood tests are needed to diagnosis
“Equine owners should talk with their private veterinary practitioners
about complying with interstate movement requirements, testing recommendations
and protecting their horses from ticks. If a horse appears to be ill,
it should be evaluated by an accredited private veterinary practitioner,”
said Dr. Hillman.