Observations on the hatching and activation of fresh Taenia saginata eggs

A method is described for the hatching and activation of Taenia saginata eggs. All proglottids collected from eight naturally-infected people in Kenya contained a high proportion of eggs with oncospheres that could be activated. A mean activation rate of 82.7% was recorded in eggs aged ten hours to ten days. Bile, in the absence of pancreatic enzymes, stimulated activation of T. saginata oncospheres but trypsin was necessary to achieve hatching from the oncospheral membrane.