Echinococcus granulosus: diagnosis of hydatid disease in man.

Several antigen fractions were prepared from sheep hydatid fluid and scolices of Echinococcus granulosus by salting out with ammonium sulphate. Sera from subjects with hydatid disease and from uninfected controls were assayed by the IHA, Latex, ELISA and Complement Fixation tests. The greatest sensitivity was given by the hydatid fluid 0.8 M fraction in the IHA test. This antigen also gave good results with the ELISA technique. Antigens from sheep fertile fluid were diagnostically superior to those from scolices. The specificity was excellent for all antigens examined.