Introduction: From May 2nd to 13th 1997, an aerial mosquito control took place in Abidjan. This mosquitoes control has been undertaken by the municipality. He made two Ultra Low Volume (ULV) applications of d eltamethrine (K O thrineR). The second application took place one week after the first one. Each application used 2g per ha of deltamethrine diluted with gasoil.
Materials and method: We evaluated the impact of this mosquitoes control on Aedes aegypti populations in two districts : Port-Bouët and Yopougon. We compared the bite number per person and per day obtained by catching mosquitoes on human from 16 pm to midnight.
Results: We thus captured 308 females of mosquitoes with 33% of Aedes aegypti representing 5.58 bites per person and per day in Port-Bouët and 2.5 bites per person and per day in yopougon. We noticed that 49% of Aedes aegypti live and bite inside. The bite number per person and per day has been reduce to 37.5% after treatment in Port-Bouët and to 66% in Yopougon. But we noted that five days after treatment the bite number per person and per day was the same level before the treatment. Aerial application of insecticide has more impact on Aedes aegypti population biting outside than the population biting inside.
Conclusion: Aerial application of insecticide reduces the bite number of mosquitoes per person and per day and in particular of Aedes aegypti but this reduction does not last long. This reduction is better on outside population than the inside one; so bio ecology studies are required before aerial application of insecticide.