Studies on variability in the susceptibility of a North American snail, Tropicorbis havanensis, Puerto Rican strain of Schistosoma mansoni

Abstract

Laboratory tests of the susceptibility of T. havanensis to infection by miracidia of S. mansoni show no signs of genetic variability in inbred lines, but do show that re-exposure may materially increase the incidence of infection. These tests also indicate that only the older juveniles and the adult snails are readily parasitized, regardless of the number of exposures furnished.