The enzyme linked immunosorbent assay (ELISA) for the determination of circulating antigen and antibody in Schistosoma haematobium-infected baboons.

The ELISA was used to measure circulating antigen and antibody in four baboons of which three were treated. The circulating antigen appeared earlier after infection than the antibody which eventually, however, reached a higher level. Both antigen and antibody levels increased slightly after treatment and thereafter declined to reach background levels eight weeks later. It is concluded that the ELISA has a potentially useful role in detecting both antibody and circulating antigen and that it may be successfully used in evaluating the efficacy of schistosomicides.