Immunization of dogs against Echinococcus granulosus using worm secretory antigens.

A new approach to the immunization of dogs against Echinococcus granulosus, using secretory antigens derived from adult tapeworms cultivated in vitro, resulted in a highly significant suppression of egg production by Echinococcus granulosus in immunized dogs. There was also a significant reduction in the number of proglottids per worm in immunized dogs. It appeared that the suppression of egg production was due to an immune effect on both somatic growth and germinal development. The implications of this work with respect to hydatidosis control programmes are discussed.