Case Report: Retrospective discovery ofIkeda inNeumann ticks on a cow-calf farm in Tennessee (US).

Abstract

Ikeda is a protozoan parasite that has recently been detected inNeumann ticks and bovine serum samples in the United States (US). This parasite is known to cause theileriosis in bovine hosts and has negatively impacted the cattle industry worldwide. The transmission of this pathogen at the livestock-wildlife interface in the US is not fully understood.Ikeda was reported by producers on a cow-calf farm in eastern Tennessee. A retrospective analysis of field- and host-collectedresulted in the detection ofIkeda in nymphalticks collected from cattle (), domestic cats (), raccoons (), and Virginia opossums (). Notably, the protozoan DNA was not found in the blood of these hosts. Multiple hosts (cattle, raccoons, Virginia opossums, and a domestic cat) contributed to the presence ofIkeda-infectedticks on the farm. Treating these hosts with acaricides could be important for reducing tick abundance and pathogen transmission. Additionally, biosecurity practices, such as changing gloves and syringes between handling bovine hosts, are important for preventing the accidental mechanical transmission ofparasites.