[Serodiagnosis of onchocerciasis by micro-ELISA using homologous somatic and metabolic antigens (excreted-secreted). Comparison with indirect immunofluorescence].

Using ELISA, we studied excreted-secreted (ES) antigens of adults O. volvulus obtained from nodules digested by collagenase and kept alive in vitro. It seems that only the female worms produce these antigens. They probably have a much higher specificity than somatic antigens (male or female worms extracts): a comparison was made in a study of 163 heterologous sera by ELISA. With this new sort of antigen the onchocerciasis serology seems to have a specificity not achieved until now. Its diagnosis value was studied with 61 proved onchocerciasis sera and 177 sera from people living in endemic areas. The percentages of positivity are 79 and 52 p. 100 respectively; the micro-ELISA is particularly advantageous for studying large numbers of sera and for seroepidemiology. We also compared the results obtained by the immunofluorescent antibody test using male and female O. volvulus and female D. viteae frozen sections. No significant differences were found in the study of these 3 antigens that have many non-specific fractions as all somatic antigens do.