Detection of Giardia antigen in stool samples before and after treatment.

A double antibody sandwich ELISA technique, using a chromatography purified Giardia antiserum, was applied to detect faecal antigen in patients infected with Giardia lamblia before and after treatment. The assay could detect antigens in 98% of infected cases with false positive reactions in 3 cases infected with E. histolytica.