Published online by Cambridge University Press: 05 June 2009
1. Biomphalaria p. nairobiensis, B. p. ruppelli and B. s. tanganyicensis have been found to be moderately susceptible to S. rodhaini from Kenya. A. glabratus from Puerto Rico is partially susceptible to the parasite. However, B. s. sudanica, B. dlexandrina, A. glabratus (Puerto Rico, albino strain) are refractory to infection with the same parasite from Kenya.
2. The present results together with those of some previous investigators suggest the existence of geographical strains of S. rodhaini.