Background: In Cambodia, recent results showed very high resistance of Aedes aegypti to temephos, the only larvicide used in Cambodia, and two adulticides (permethrin used for net treatment, and deltamethrin for insecticide fumigation). The Ecomore2 project in Cambodia aims to estimate the effectiveness of an integrated vector management (IVM) targeting schools combined with an educational program to mitigate peaks of dengue and dengue-like syndromes (DLS) for reducing subsequent overcrowding of health centers. Methods and materials: A cluster randomized controlled trial was implemented in 24 clusters (12 under integrated vector control and 12 without), each including one school, with an active surveillance of DLS in neighboring villages. Our research program was also implemented to determine if an IVM could decrease the number of Ae. aegypti mosquitoes in schools by using Bacillus thruringiensis var. israelensis as a larvicide, pyriproxyfen for the dissemination of insect growth regulator larvicide and spores of Beauveria bassiana for slowly killing adults; all these methods were combined with education and sensitization of children. Results: Monitoring of mosquito populations during the first year showed the presence of at least 58 mosquito species, including dengue virus vectors such as Ae. aegypti and Ae. albopictus, but also vector species of Plasmodium spp., and Japanese encephalitis, Rift Valley Fever, West Nile Fever, Zika, Chikungunya and Ross River viruses. Ae. aegypti and Ae. albopictus were present in all 24 schools. There was no difference in the relative abundance of Ae. aegypti and Ae. albopictus between the clusters before the intervention. In parallel, epidemiological data neither showed any baseline difference of DLS. Entomological data following IVM showed a decrease of 50% of Ae. aegypti relative abundance in treated clusters compared to untreated clusters. The latter showed an average relative abundance of Ae. aegypti similar to the first year. The difference for Ae. albopictus relative abundance was not significant between the 2 areas. Epidemiological final data analysis are in progress, but will be presented for the ICID conference. Conclusion: In conclusion, the IVM decreased the Dengue vectors in schools in Cambodia. The epidemiological results of dengue incidence in the 2 clusters will be discussed during the conference.
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