The potential use of sterile hybrid males for the eradication of member species of the Anopheles gambiae complex.

The eradication of certain insect pests of medical importance has already been achieved in some countries by inundation of the natural populations with sterilized insects.The crossing of member species of the Anopheles gambiae complex results in the production of vigorous competitive males which are sterile. Crosses between the males of the freshwater species, provisionally called species A and B, and the females of the saltwater species A. melas and A. merus result in F(1) generations almost entirely composed of males, which again are sterile.This paper reports the results of cage experiments in which adult sterile males from these latter crosses were added to normal males and females in varying proportions and larval seeding experiments in which larvae known to produce virtually nothing but sterile males were added to normal larvae in varying proportions, reared together and the adults allowed to emerge together and mate.Both series of experiments resulted in a significant reduction in the fecundity of the females and, in the adult series, strong evidence of superior mating ability of the sterile males was given.The potentiality of this method of species eradication is discussed in relation to present difficulties experienced in the control or eradication of A. gambiae-transmitted malaria.