A Comparison of Two Geographical Strains of Schistosoma haematobium

Abstract

A comparison of the characteristics of two strains of S. haematobium in experimental infections in hamsters is made. A limited study of these strains is also made in Mastomys.Growth changes in male and female adult worms are compared, as are changes in the uterine egg counts.The quantitative distribution of eggs in the tissues of the hamster is recorded. The approximate mean daily egg output per female worm for each strain is calculated at specified time intervals, and for the entire period of observations.The recorded characteristics of the two strains of parasite are compared with those described for other strains of S. haematobium.It is considered that the hamster provides a useful model for such studies provided that standardised infection procedures are employed.It is considered that differences in host characteristics and susceptibility of individual animals account for the apparent variability recorded with regard to growth of parasites and egg depositions.