Summary

On the greater part of the coast of British Guiana, close association has hitherto existed between hydrological bonification and hyperendemic malaria, except on the eastern coastlands. Residual DDT house spraying, as the sole means of control, brought about the elimination of A. darlingi and Ae. aegypti, and an economic technique of control maintenance by “strategic barrier” spraying was gradually developed.

In 1951, A. darlingi reappeared suddenly in small numbers on the eastern coastlands in the wake of artificial changes in conditions of physical and human ecology in a localised area. Prompt spraying of houses in the villages and along the path of invasion eliminated a potentially dangerous threat from A. darlingi-borne malaria in the district. This incident confirmed rather than weakened the principle of “strategic barrier” spraying in British Guiana.