Hotspots of Aedes aegypti (Diptera: Culicidae) larvae in Abidjan, Southern Côte d'Ivoire

Abstract

During the last 10 years, Abidjan District has been a focus of dengue and yellow fever epidemics. To better control the vectors, identification of urban areas having the highest density of Aedes mosquitoes is essential. Geographical coordinates of larval habitats sampled within the ten municipalities of Abidjan allowed geostatistical analysis to build an ordinary kriging. Larva were classified at genus levels, counted, and reared until adult emergence for species identification. A total of 37,158 mosquito larvae from the ten municipalities were collected and identified to genus. Aedes aegypti was the most widely distributed species, being found in 60 to 80% of habitats such as rubbish dumps, banana plants and unused tires. A high larval density (more than 100 Ae. aegypti larvae/liter) was predicted in Abidjan except the South-West of Abobo and Adjame. Moreover, high larval densities of 234-350 Ae. aegypti larvae/liter were predicted in Cocody.A very strong spatial heterogeneity was observed for Ae. aegypti in Abidjan City. The ease of international travel in high-standing municipalities and the presence of vulnerable communities in poor municipalities could increase the risk of epidemic emergence.