Development of an experimental tissue culture vaccine against Mediterranean theileriosis in Spain.

Vaccines against Mediterranean theileriosis have been developed in several countries where the disease is an economic problem. Tissue culture vaccines have been widely and successfully used to immunize cattle. Although Mediterranean theileriosis represents a constraint to dairy cattle production in Spain, no vaccines against this disease have been developed previously. The successful development of a tissue culture vaccine consisting of attenuated Theileria annulata schizont infected cells from an enzootic area of Spain and its efficacy under experimental conditions is reported. Vaccinated calves were resistant to homologous challenge showing no signs of theileriosis while non-vaccinated calves showed typical signs of disease.