The specific serum
IgG1,
IgG4, and
IgE responses to Dracunculus medinensis and the level of total
IgE of individuals living in a highly endemic area of northern Ghana were measured by ELISA. Sera were obtained in the high transmission season from individuals with prepatent, patent, or postpatent
infection as well as from individuals from the same endemic area who claimed to have never had a patent
infection (i.e., endemic normal individuals). Individuals with prepatent or postpatent
infections responded with a significantly lower mean level of specific
IgG1 and
IgG4 compared with individuals with a patent
infection, and with a significantly higher mean level of specific
IgG1 and
IgG4 compared with endemic normal individuals. For specific
IgE, no differences were found in the mean antibody level between the
infection status categories. Individuals with a patent
infection had a significantly lower mean serum level of total
IgE compared with prepatent, postpatent, and endemic normal individuals. Endemic normal individuals had the highest mean level of total
IgE. Furthermore, in all clinical categories, high responders for specific
IgG1 and
IgG4 generally had low levels of total
IgE, whereas low responders for specific
IgG1 and
IgG4 generally had high levels of total
IgE. A similar dichotomy, although less distinct, was observed between specific
IgG1 and
IgG4 on the one hand and specific
IgE on the other. Thus, similar to what has been suggested for
schistosomiasis and
lymphatic filariasis, the relationship between the
IgG subclasses and
IgE appears to play a role in, or at least to reflect, a mechanism for protective immunity in
dracunculiasis.