Effects of Lambdacyhalothrin Incorporated into 1, 4-Dichlorobenzene on Sand Fly and Mosquito Vectors in Endemic Areas of Kenya

No new public health insecticides have been developed for mainstream vector control in disease endemic countries for 30 years. Marigat study site is an area that is endemic for both cutaneous and visceral leishmaniasis while Mwea is a malaria endemic area. Both sand flies and mosquito collections were carried out in the study households before interventions and after interventions using the CDC light traps. Effects of lambdacyhalothrin incorporated into 1, 4-dichlorobenzene on sand fly and mosquito vectors were evaluated in three phases: Immediately after treatment, 2-3 months and after 6 months post treatment. Vector collections were carried out before and after interventions, they were then counted identified and recorded. The sand flies and mosquito densities decreased significantly when exposed to PCB/ICON combination as opposed to ICON and PCB alone. The mean numbers of sand flies and mosquitoes collected from houses with in PCB/ICON combination was less as compared to PCB and ICON independently. From the results, there was a synergistic effect observed when lambda-cyhalothrin (ICON®) and 1, 4-dichlorobenzene (PCB®) are used in combination as compared to their individual treatments. This indicates that combinations are more effective in controlling vectors of malaria and leishmaniases diseases.

Keywords: Lambdacyhalothrin, 1, 4-dichlorobenzene, leishmaniasis, and malaria, sand flies, mosquitoes.