Theileria orientalis vaccine development potential

Summary

Bovine theileriosis caused by Theileria orientalis appears to be an emerging disease condition in eastern Australia and a sustainable method of control such as a vaccine is urgently needed. There are three variants of this parasite present in this country but only one is associated with disease. The purpose of this study was to determine from the literature how feasible the development of an effective subunit or live vaccine was likely to be. Not enough is known of the immune mechanisms of animals infected with Theileria for a subunit vaccine to be an option at the present time. However, development of a live vaccine based on one or more of the benign variants is worth considering even though significant differences exist between the variants. We recommend that the latter be progressed firstly by looking for evidence of cross-immunity between variants in small-scale pen and field trials. If there is cross-immunity, the technology exists in Australia to develop, register and produce a live vaccine.