P 22 - Laboratory evaluation of efficacy of the larvicide spinosad against Anopheles stephensi in Jigjiga, Ethiopia

We report the efficacy of a commercial formulation of the insecticide spinosad against larvae of Anopheles stephensi from populations found in the city of Jijiga, Somali Region, Eastern Ethiopia. Batches of 25 larvae (late III to early IV instar) collected from large water storage reservoirs associated with construction sites (the primary An.  stephensi larval site in the dry season) were tested under laboratory conditions against each insecticide at a dose recommended by the manufacturer (Natular® G30, 0.02 gr/5L) following WHO guidelines. Mortality at 24-48 h post-exposure was 100%. Results show that Spinosad is effective against An. stephensi larvae and suggest that it may be a useful tool as part of larval source management plans aimed at controlling this invasive malaria vector in Ethiopia.