[Impact of the use of larvivorous fish Poecilia reticulata on the transmission of malaria in FIR of Comoros].

Field tests were conducted in the Grande Comore Island, Federal Islamic Republic of Comoros, in order to evaluate the potential of the larvivorous fish Poecilia reticulata for the control of the malaria vector Anopheles gambiae s.s. Due to the high permeability of soil, Anopheles breeding sites in all island occurs only in the man-made water reservoirs. The study was carried out from November 1987 to November 1988 within a framework of a malaria and filariasis control programme, supported by WHO and UNDP in collaboration with the Government of the FIR of Comoros. All larval breeding places of An. gambiae existing in the village of Hantsambou were recorded (59 ablutions basins and 61 cisterns) and provided initially with 3-5 specimens of P. reticulata/m3 in November 1987, after the importation of the larvivorous species from Mayotte Island. The percentage of breeding places positive for An. gambiae decreased from 41% to 6% after one year. Pyrethrum spray catch showed a reduction of indoor resting density from 5.5 to 0.3, while the ma value, number of Anopheles bites/man/night, obtained by night-biting catches, decreased from 6.3 to 1.2. At the same time of the reduction of entomological indices parasite index for P. falciparum and spleen rate drop steadily in 5-9 years school children. The tested vector control method, well accepted by the community, could be implemented in malaria control through primary health care, being the ecological conditions in the entire island very peculiar.