Ultrastructure of Theileria-infected blood cells of loggerhead turtles

This report regarding theileriosis is based on observations that were made over a period of about 12 years and includes an analysis of multiple hematological parameters derived from a large number of C. caretta obtained from inhabitants of the Mediterranean Sea. The diagnostic process of theileriosis began with the detection of eosinophilic leukocytosis, followed by the recognition bacillary rod-bayonet-shaped inclusions first in circulating erythrocytes and then in leukocytes. When the stage of infection visually affected the leukocytes in the blood smears, buffy coat preparations of both subjects were prepared and cultured. The results of these tests confirmed the presence of an intense proliferation of transformed cells containing parasite particles over a period of several months. TEM observations of blood cells demonstrated Theileria infestation of the two C. caretta.