Equine Piroplasmosis as an Emerging Infectious Disease

Presentation Description / Summary: Equine piroplasmosis is an infectious disease caused by the protozoan parasites Theileria equi and Babesia caballi. More recently, a new species, Theileria haneyi, has been identified. While the disease is generally considered exotic to the US, it has reemerged through tick-borne and iatrogenic transmission. Furthermore, lack of testing at ports of entry into the US are likely enabling infected horses to cross the border into the US and likely other countries as well. Current treatment strategies utilized for chemosterilization of T. equi and B. caballi infected horses have failed to clear T. haneyi. Furthermore, the challenges of superinfect compound efforts of clearance, and resistance of T. equi to imidocarb appears to be growing (is that a true statement?) This session will review the epidemiology and pathophysiology of piroplasmosis in horses and discuss the treatment options, specifically focusing on experiences and observations from regions where T. equi and B. caballi are endemic. Furthermore, future risks including the spread of T. haneyi as well as the wider geographic distribution of T. equi and B. caballi due to climate change and globalization and the consequences for the US and European horse population will be discussed.

Learner Outcomes: Understand the life cycle and pathophysiology of Th. equi and B. caballi. Understand the treatment options available for acute and chronic equine piroplasmosis. Assess the future risk of equine piroplasmosis becoming endemic in the United States and Europe.