SEROLOGICAL DIAGNOSIS OF SCHISTOSOMA-JAPONICUM INFECTIONS IN CHINA

This paper reports the results of the dot enzyme-linked immunosorbent assay (dot-ELISA) for the serological diagnosis of 50 acute and 50 chr onic Schistosoma japonicum-infected patients employing keyhole limper haemocyanin (KLH) and soluble egg antigen (SEA) as the specific antige ns. The sensitivity of both antigens for the detection of both forms o f this infection was 100% and 90%, respectively, using a test serum di lution of 1:100. When the serum dilution was adjusted to 1:500, the se nsitivity of the KLH dot-ELISA was 82% and 15%, respectively. Thus, th e different manifestations of this disease can be easily distinguished . None of the 44 uninfected control sera gave a positive result with t he KLH dot-ELISA, though 6 (14%) did so with the SEA dot-ELISA. Cross reactivity rates of 13% and 23% were observed for clonorchiasis (n=30) and paragonimiasis (n=22). Therefore, the overall diagnostic effectiv eness of both the KLH dot-ELISA and SEA dot-ELISA for the detection of S. japonicum infection in endemic regions in China was 97% and 92%, r espectively.