Theileria orientalis Ikeda genotype was identified for the first time in the United States in Virginia in 2018. Theileria is a tickborne parasite of cattle that causes anemia, death, and abortions. The exotic longhorned tick is the primary vector of this pathogen. While this is not a risk to human health, it has the potential to lead to significant economic impacts in the cattle industry.

This page will be updated regularly in order to give you the most recent information.  Please feel free to contact Virginia Tech Animal Laboratory Services if you have questions or comments or if you have particular topics that you would like us to discuss.

There have been increased numbers of stillborn and undersized calves in the region this fall.  There has been association between Theileria orientalis Ikeda and abortions in cattle, but the pathogenesis and frequency has not been researched.  We are interested in obtaining samples from aborted/stillborn calves and their dams.  Please contact your veterinarian to submit fresh/frozen spleen from the fetus, EDTA blood from the dam, and formalin fixed placenta when available.  If we received these with a history and indication this is for our research study, we will test the samples free of charge.  Please feel free to contact ViTALS with any questions.

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