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Sera from patients with schistosomiasis and various infections were examined by an enzyme-linked immunosorbant assay technique (ELISA) using soluble antigens prepared from adult worms and eggs of Schistosoma mansoni. Marked false positive reactions were observed in cases of certain parasitic (hydatidosis) and non parasitic diseases (liver cirrhosis). Equivalent results with the techniques of immunofluorescence and immunoenzymology (done on adult sections) were obtained with adult worm antigen read at a higher optic-density limit. At present, this technique might be useful in seroepidemiological surveys; however, further purification of the antigen will increase its sensibility and specificity.

The authors note a very high prevalence of schistosomiasis mansoni in the two foci studied in Togo (Lama Kara in the North and Kpalimé in the South-West); however, the prevalence is significantly higher in Lama Kara (79.5%) than in Klonou (54.7%); this was calculated on both coprological and serological basis. The parasite burden is identical in the two foci; but, the GMRT is higher in Lama Kara than in Klonou (31.7 and 8) which might be explained by a different immunogenicity of the two strains. It is noticed schistosomiasis mansoni might be responsible for hepatosplenomegaly found in the two foci, especially in Lama Kara, which might be explained by a higher virulence in this location. The treatment by oltipraz (RP 35972) had a 91.9% success rate in Klonou (similar to our results in Paris). However, in Lama Kara, even though the drug was taken with some food--increasing its biodisponibility--, the treatment was less effective at day 180 (76.5%). The authors wonder whether the difference of oltipraz efficiency between the two foci is based on a difference of biology between the two strains of Schistosoma mansoni in Lama Kara and in Klonou.

The authors study the results of a treatment of 700 cases of bilharziasis seen in Paris and in two foci in Togo, by oxamniquine, oltipraz or praziquantel. The three drugs are well tolerated; only a few mild side-effects were reported such as discomfort, nausea, headaches (two cases of acrodynia with oltipraz ). The three drugs are very efficacious in the case of schistosomiasis mansoni (85,5% success rate with oxamniquine, 92,9% with praziquantel, from 76,5 to 92% with oltipraz depending on the different strains) at day 180. As far as schistosomiasis haematobium is concerned, oltipraz and praziquantel have a 87,5% success rate with oltipraz and 80% with praziquantel; however, in the case of oltipraz , it is necessary to increase the dose. The action of praziquantel seems to be slower on Schistosoma haematobium than on S. mansoni. By the study of the evolution of antibodies, the fast action of praziquantel was noticed, explaining the peak of serological titers and of eosinophilia as early as day 10 after treatment; in the case of oltipraz , the apparition of this peak is only recorded at the 30th day. The slower effect of oltipraz on worms implicates not to judge its efficacy by too early controls.