ANTIBODY-RESPONSE PATTERNS AGAINST SCHISTOSOMA-MANSONI IN A RECENTLY EXPOSED COMMUNITY IN SENEGAL

Acquired immune resistance is believed to be largely responsible for a ge-dependent infection and reinfection patterns in schistosomiasis, In a recently established but intense focus of Schistosoma mansoni in Se negal, the humoral immune response was studied in a random population sample of 289, Antibody levels of various isotypes to schistosome worm and egg antigens were determined by ELISA and related to egg counts ( eggs per gram of feces [EPG]), age, and sex, Both IgG1 and IgG4 follow ed age-related patterns similar to egg counts and strongly correlated with EPG, even after allowing for age, Specific IgE levels increased s lowly with age, The humoral immune response patterns in this recently infected population appeared to be largely similar to those in chronic ally infected communities, Thus far, the observations do not support t he current hypothesis that age-related resistance to Schistosoma is de termined by IgE-mediated protective immunity acquired during many year s of exposure.