[The closed hexagon immunodiffusion (CHI) for the diagnosis of onchocerciasis (author's transl)]

1273 sera from microfilaria-positive and -negative persons living in an onchocerciasis-endemic area in Liberia were examined. For this purpose a modification of the Ouchterlony-test was performed and compared with other methods. In the complement-fixation test many sera showed complement inhibition without any possibility to eliminate it. There were considerably varying titers in the indirect hemagglutination test. This helped to distinguish groups with different correlations to microfilaria-findings. The closed hexagon immunodiffusion after TRAAVIK, SIEBKE and KJELDSBERG (1972) - a modified OUCHTERLONY-test - proved to be nearly as good as indirect hemagglutination. An advantage of the CHI test is that it is easy to carry out. CHI reacted in 64% of microfilaria-positive and in 25% of microfilaria-negative cases.