Vaccines against hemoparasitic diseases in Israel with special reference to quality assurance.

Four vaccines against hemoparasitic diseases (anaplasmosis, babesiosis and theileriosis) and a vaccine against besnoitiosis are currently used in Israel. These vaccines contain live attenuated parasites derived from cell culture (Theileria annulata and Besnoitia besnoiti) or from blood of infected, splenectomized calves (Babesia bigemina, B. bovis and Anaplasma centrale). Cryopreserved master seed is used to initiate production of the vaccines. Quality control performed during the preproduction period is particularly important with blood-derived vaccines. Post production quality control comprises sterility, potency (viability of immunizing organisms), safety (degree of attenuation) and efficacy (capacity to protect against virulent parasite stock). All vaccines are stored and dispatched to the field in a concentrated frozen state. The culture-derived vaccines are safe for all varieties of cattle, regardless of age or physiological condition, whereas the blood-derived vaccines are recommended mainly for young cattle, the age limit varying with the type of vaccine and breed of cattle. The viability of T. annulata infected cells in the anti-theilerial vaccine is tested after thawing by in vitro plating efficiency and the infectivity of blood-derived vaccines is tested by titration in susceptible cattle.