Leukocyte adherence to Schistosoma haematobium eggs from children.

The pattern of leukocyte adherence to voided Schistosoma haematobium eggs was compared in children 7-16 years old. A method enabling the measurement of the intensity of adherence was first developed by means of scanning electron microscopy, after which it was adapted for light microscopy. The intensity of adherence decreased from younger to older age groups. This result was unexpected, and has bearing on contemporary views on immunity to human schistosomiasis, particularly the blocking antibody theory.