Observations on possible immunity to reinfection among school children after schistosomiasis treatment.

A total of 72 bilharzial mansonian school children aged 6-12 years were studied before and six months after praziquantel (PZQ) treatment. After treatment, 21 cases showed reinfection while 51 were resistant. Using ELISA specific antibody assays titre levels of IgM, IgG, IgA & IgE for soluble egg antigen (SEA) and soluble worm antigen (SWAP), were higher among resistant cases than among reinfected ones before and after treatment. The levels of specific IgA & IgE among resistant cases were significantly higher than among reinfected cases after treatment. This may indicate the integrity of immune system and prominant humoral immune response.