Preliminary Report on the Reduction of Adult Mosquitoes in Housing Compounds in Western Kenya Using the ProVector Flower and Entobac Bait Pads Containing Bacillus thuringiensis israelensis With Honey Bait

Reducing mosquito populations indoors and outdoors can have a significant impact on malaria and other mosquito-borne diseases. A new formulation and delivery system for Bacillus thuringiensis israelensis (Bti) was tested against adult mosquitoes. One Entobac bait with 7% Bti in a honey solution was placed within each ProVector Flower applicator. The applicators were placed in nine housing compounds, one on the outside of each home in Ahero and Nyalenda, Kenya, in June 2009. Seven housing compounds with no applicators were included as controls in the study area. After 1 mo, there was a significant reduction of mosquitoes in all nine compounds with the ProVector Flower compared to two of the seven control compounds. The overall mosquito population was reduced by 69% in housing compounds with the ProVector Flower whereas the mosquito population grew by nearly 15% in the control compounds. There was a significant reduction of the median number of mosquitoes in the test compounds than in the control compounds. The proportion of mosquitoes collected was significantly reduced in the test compounds within 1 mo for several species of Aedes, Anopheles, Coquillettidia, Culex, and Mansonia. This study provides evidence that Bti-laced bait may be used as an alternative adulticide and be delivered in an applicator to reduce mosquito populations of several species. This method may significantly reduce the cost of pesticide application through target specificity and by reducing the amount of pesticide placed into the environment.