Piroplasmosis Horses Remain Missing, Canada Adds Equine Import Requirements

The two horses removed from piroplasmosis quarantine in Missouri on June 17 had not been located as of June 30, said Tim Cordes, DVM, senior USDA staff veterinarian for Equine Programs and national coordinator for Equine Diseases. Multiple agencies, including the USDA, Missouri Department of Agriculture, and the Federal Bureau of Investigation, are involved in the search.

The two horses tested positive for equine piroplasmosis after another horse stabled at the Raytown Equestrian Park was hospitalized and confirmed positive for the disease, setting off a foreign animal disease investigation.

The stable, home to 64 equids, was quarantined June 6, and equine piroplasmosis (caused by Theileria equi) was confirmed in the affected horse June 10. Five positive horses were euthanized June 18 with their owners' consent.

Whoever took the positive horses removed locks on the stable and stall doors to access the animals, according to a statement released by the Missouri Department of Agriculture.  

Misti Preston, public information administrator with the Missouri Department of Agriculture, described the horses as bay Quarter Horse geldings. One had a star and one had a blaze. The horses are microchipped. No other information was available.

Equine piroplasmosis is an infectious disease that can be caused by two different protozoal parasites that attack the red blood cells (the one causing the current outbreak is Theileria equi). It is characterized by fever, anemia, weight loss, jaundice, and, in some cases, death. The case fatality rate can be up to 20% in naive horses. The only treatment is a potent type of chemotherapy that can have serious side effects in some horses.

The disease is spread by ticks, the use of contaminated needles, and possibly through blood-contaminated semen of infected stallions. Infected ticks pass the parasite while feeding. Read more about piroplasmosis.

Equine Canada reported the Canadian Food Inspection Agency (CFIA) on June 22 asked the USDA to suspend the issuance or endorsement of export certificates for horses and other equines coming from Missouri.

The USDA has also been asked to certify horses and other equines entering Canada from other states with the statement: "During the previous twenty-one (21) days, the animal(s) in this shipment has/have not been in the State of Missouri."

The Canadian Border Services Agency will ask all those transporting horses into Canada the following questions:

1. Do the horses originate from the state of Missouri or have they been in that state within the past 21 days?

2. Have the horses transited the state of Missouri en route to Canada?

If the horses originate or have been in the state of Missouri within the past 21 days, or have transited through it, they will be referred to the Canadian Food Inspection Agency. That organization will determine, based on document verification and inspection, whether the horses should be allowed to enter Canada.

Equine Canada strongly recommended that horse owners who wish to bring their animals to Canada avoid traveling to, or transiting through, Missouri with their horses. Horse owners who still want to export their horses to Missouri cannot bring them back to Canada on the original Canadian export certificate. Instead, they will need to move their horses to a non-affected state for at least 21 days prior to returning to Canada.

Current import requirements for horses entering Canada can be found using the CFIA Automated Import Reference System at airs-sari.inspection.gc.ca. To determine import requirements for each horse, specific parameters that refer to each horse's individual circumstances need to be entered to create a customized import requirement list.

About the Author

Erin Ryder

Erin Ryder is a former news editor of The Horse: Your Guide To Equine Health Care.

Stay on top of the most recent Horse Health news with FREE weekly newsletters from TheHorse.com. Learn More