Abstract
Regular aerial treatment of 14000 km of watercourses has achieved and maintained, over an area of 700000 km
2
of West African savannah, a very high degree of control of the larvae of
Simulium damnosum
sensu stricto and
S. sibanum
, the vectors of onchocerciasis in this area. However, particular and relatively restricted parts of this area, mainly in northern Ivory Coast and neighbouring parts of Upper Volta, experience regular and prolonged reinvasions by parous female vectors, which have already taken bloodmeals (and many of them carrying the parasites) and arrive from unknown sources probably hundreds of kilometres away, from directions probably between southwest and north. This reinvasion, now experienced in three successive years, represents the outstanding scientific, epidemiological and logistic problem still facing the WHO Onchocerciasis Control Programme. An outline is presented of the multidisciplinary investigations being undertaken to find a solution.
Subject
Industrial and Manufacturing Engineering,General Agricultural and Biological Sciences,General Business, Management and Accounting,Materials Science (miscellaneous),Business and International Management