ABSTRACT

During the first months of a child's life passive immunity from the mother confers some protection. However, parasite numbers soon increase and the mortality in hyperendemic areas is highest during the first years of life. By school age, children have developed considerable degree of active immunity (Bmce-Chwatt, 1 952; Lucas et aI. , 1969) . This gradually acquired immunity is manifested by lower parasite densities , fewer clinical

Persisting infection in the immune host

terized hy a lower peak parasitemia lasting for a shorter duration. These observations collectively argue that antigenic variation is not a major mediator of the host-parasite equilibrium.