Complementary Effects of Crude Ethanol Phytolacca dodecandra Extracts with House Characteristics on Densities of Indoor Resting Mosquitoes in Western Kenya

Abstract: Intensive use of insecticide treated nets, indoor residual sprays and timely treatment of malaria patients saw reduced malaria parasitaemia from 11% to 8% by 2015. However, sorry housing characteristics in a number of homesteads in Kenya, threaten this. This study meant to evaluate the complementary effect of crude ethanol Phytolacca dodecandra (Endod) extracts with housing characteristics on density of indoor resting mosquitoes. A completely random block design was used to sample experimental houses and a four by seven factorial design used to sample indoor resting mosquitoes using resting boxes treated with Endod extracts. House characteristics and Endod treatments were taken as independent, mosquitoes as dependent variable and unsprayed (plain) resting boxes as control. Of recovered mosquitoes, Culicines (4.41 ± 0.03) were more abundant than Anophelines (2.65 ± 0.04). High [(3.05 ± 0.14), anopheline (5.03 ± 0.35), culicine] and least [(2.83 ± 0.14), anopheline (3.48 ± 0.21), culicine] mosquitoes were found in houses without and with highest number of nets respectively. The numbers however, differed significantly [(df=1; F=27.436; p < 0.001), no net (df=1; F=6.669; p < 0.012), three nets] irrespective of species. Most anophelines (2.32 ± 0.09) and Culicines (3.73 ± 0.26) were found in houses with open and closed eaves respectively. It is concluded that effectiveness of crude ethanol Endod extracts on indoor resting mosquitoes is dependent on house characteristics, that crude extracts of Endod repels mosquitoes and that it could be used as an alternative insecticide to reduce the risk and burden of mosquito borne infections. Key Words: Phytolacca dodecantra Anopheline, Culicine, Crude Extracts, House characteristics, Resting boxes