Genetic Control of Schistosomiasis: A Technique Based on the Genetic Manipulation of Intermediate Host Snail Populations

  • David S. Woodruff
Part of the Comparative Pathobiology book series (CPATH, volume 8)


In this contribution I support the contention (Woodruff, 1978) that it may be possible to reduce the size of human-infecting schistosome populations by the genetic manipulation of their intermediate host snails. The proposed technique is based on the finding that snail-schistosome compatibility is variable and that some of this variation is under relatively simple genetic regulation. If the proportion of intermediate host snails that are resistant to infection by the local larval schistosome can be increased, then the rate at which the parasite is transmitted to the final host will decrease. Such genetically resistant snails can be isolated by artificial selection procedures, mass-reared, and their descendants returned to the population from which they were isolated. If sufficient numbers of resistant snails are released, the resultant genetic perturbation will be too great for the local schistosome population to adjust coevolutionarily. Under certain local ecological circumstances it may be possible to break the transmission cycle within a few years.


Genetic Control Intermediate Host Schistosoma Mansoni Schistosoma Japonicum Host Snail 
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Copyright information

© Plenum Press, New York 1985

Authors and Affiliations

  • David S. Woodruff
    • 1
  1. 1.Department of BiologyUniversity of California, San DiegoLa JollaUSA

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