Theileria orientalis Ikeda Genotype: Implications for Cattle Health in Virginia

Of the four most economically important tickborne diseases of cattle in the world, two have been identified in Virginia, occasionally as co-infections: anaplasmosis and theileriosis. The latter is caused by the emerging infectious agent, the Theileria orientalis complex, in particular the Ikeda and Chitose genotypes. These organisms are carried by the ixodid tick, Haemaphysalis longicornis, recently identified in the United States. Our work has been focused on initially identifying the protozoal organisms, crafting assays to aid in the identification of these organisms in clinically affected animals, and briefly examining the rate of co-occurrence of theileriosis and anaplasmosis. This is important, as Anaplasma marginale - the most common etiologic agent of anaplasmosis in cattle in Virginia - is treatable with a safe, effective, FDA-approved compound, whereas there is no currently approved treatment for theileriosis. Finally, we seek to contextualize theilerosis as a cause of infectious bovine anemia (IBA) and its expected economic impact on the cattle industry in Virginia.