The Sterile-Male Technique Against Tsetse Flies, Glossina Spp.

Abstract

Simpson (1958) discussed the relationship between the biological characteristics of the genus Glossina and the use of the sterile-male technique in the control of this vector of trypanosomiasis, as did Knipling in an informal report in 1963 on Practical Role of the Sterility Principle for Tsetse Fly Eradication in WHO/Vector Control/27. Knipling estimated that an initial overflooding ratio of sterile to wild males of 3: 1 with successively smaller releases could eradicate a low-density population of flies in 12 months (Table 1) at a cost of about 125/mile2, even if the sterilized males cost as much as 5 cents each. With larger populations, other methods would have to be used to reduce the density before the releases of sterile males. Also, Knipling (1964) emphasized the economic advantage that would be gained by reduction in the total number of sterile males required if their release were preceded by a single application of a nonpersistent insecticide which would eliminate most of the adult population. When populations cover a wide area, simultaneous treatment of the entire infested area might not be feasible. A more realistic approach (Table 2) could be to systemically expand small control areas along a common front (Dame 1968).