Laboratory and semi-field evaluation of Bacillus thuringiensis (Bioflash®) against Anopheles stephensi (Diptera: Culicidae) in an endemic malarious area of Iran

Background: Anopheles stephensi is considered to be the main malaria vector in the Middle East area including Iran. We aimed to evaluate the efficiency of a granule 10% formulation of Bacillus thuringiensis against this species under laboratory and semi-field conditions in an endemic malarious area of Iran. Method: After collecting mosquitos from Hurmudar, in order to find the best effective dose, five dosages (a quarter-dose, half dose, recommended dose, a twice-dose and four times dose) were used for laboratory and semi-field assays in Bandar Abbas. Results: Recommended dose by factory (0.017 g /0.1 m2) showed the highest mortality rate on An. stephensi larvae in both assays. The efficiency of Bt was very low (21 %) under semi-field condition. According to the results of this study, the use of bacteria alone cannot be a useful and effective way to control the vector of malaria in Iran's geographic conditions. Conclusion: This method can be used (in the case of appropriate efficacy of the tested formulation in field condition) as one of the constituent parts of Integrated Vector Management (IVM) program along with other recommended methods.