Serological diagnosis of Schistosoma mansoni infection: Conglutinative complement absorption test in human and experimental infections*

The conglutinative complement absorption test, using adult worm antigen (Schistosoma mansoni), was performed on the sera of 100 bilharziasis patients and of 111 non-infected individuals. If the sera that inhibit conglutination when diluted to 1: 40 or more are considered as reactive, the sensitivity of the test is 93.7% (six sera were anticomplementary). No reactive sera were found among the control group. In mice experimentally infected with S. mansoni, specific inhibition of conglutination began about the thirtieth day after exposure, when sexually mature schistosomes, migrating from the liver to the mesenteric vessels, were able to lay eggs.