The Complement Fixation Reaction in Schistosoma japonicum with Cercarial Antigen prepared from Oncomelania hupensis

Abstract

1. The preparation of a cercarial antigen from infected livers of Oncomelania hupensis the intermediate host of Schistosoma japonicum in China is described.2. The sera of 49 human beings and five dogs have been investigated for the Schistosome complement fixation reaction, using as antigens Bilharzial cercarial antigen, and an alcoholic extract of the livers of Oncomelania hupensis infected with cercariae of S. japonicum.3. Thirty-seven of the 49 sera examined were from cases of Schistosomiasis, and of these 24 gave a positive complement fixation reaction, and 2 others a weak reaction.4. Of the five dogs examined three were infected with Schistosoma japonicum. These gave positive reactions.5. In 24 cases both antigens were used, and the results obtained were almost identical.6. The Bilharzial antigen was used in 33 cases including 25 cases of Schistosomiasis, of which 19 gave a positive reaction.7. In 40 cases the Oncomelania antigen was used. This series included 32 cases of Schistosomiasis of which 23 gave a positive reaction and 3 a weak positive reaction.8. Negative results were obtained with 50 strongly positive Wasserman sera, and with 2 cases of infection with Fasciolopsis buski, and two cases of Clonorchis sinensis. Ascaris and hookworm infestations also gave negative results.