Application of the enzyme linked immunosorbent assay (ELISA) for the serodiagnosis of Schistosoma mansoni infections in St. Lucia.

As part of our search for a serodiagnostic assay to replace the expensive and tedious stool examination in the diagnosis of Schistosoma mansoni infection, we have studied the sensitivity, specificity and quantitative features of an enzyme linked immunoassay (ELISA) using crude S. mansoni egg antigen preparation. Results of studies carried out in both London and St. Lucia indicate that the assay can give useful serodiagnostic information ranging from 82 to 99.5% sensitivity, depending on level of infection intensity and method of blood collection and 100% specificity in St. Lucian/St. Vincent populations. The St. Lucia study also showed that the assay could be operated in a qualitative form in an endemic area.