title: Human schistosomiasis: potential consequences of vaccination.
abstract: The potential outcomes of a Phase II schistosomiasis vaccine trial are explored using mathematical models which assume some natural immunity and a vaccine providing partial protection for a limited time. Analyses suggest that vaccination may have only a limited impact on life-long cumulative worm burdens and may lead to increased susceptibility and higher worm burdens at some ages, a "rebound" effect which results reduced opportunity to acquire natural immunity. There is a trade-off between the degree and duration of vaccine-induced protection; long-lived vaccines may be preferable to vaccines giving greater protection but for a shorter time.
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000818:Animals; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D008433:Mathematics; D008954:Models, Biological; D012547:Schistosoma / Q000276:immunology*; D012552:Schistosomiasis / Q000517:prevention & control*; D014611:Vaccination; D014612:Vaccines / Q000276:immunology*
chemical_list: D014612:Vaccines