Bacillus thuringiensis israellensis (Bti) for the control of dengue vectors: systematic literature review
Evidence to recommend the use of Bti as a single agent for the long term control of dengue vectors and prevention of dengue fever is insufficient. Still, Bti can be effective in reducing the number of immature dengue vectors in targeted containers.
Dengue is a vector borne disease whose transmission can be prevented either by chemical or biological agents. Biological agents, such as the baccilus thuringiensis israellis (Bti) – a grampositive, spore-forming entomopathogenic bacterium – has demonstrated high efficacy against target organisms like mosquitos and fly larvae. The objective of this study was to systematically review the effectiveness of Bti used as a single agent, for the control of dengue vectors and prevention of dengue fever. Fourteen studies were reviewed (8 classified as efficacy studies and 6 classified as effectiveness studies). 4 effectiveness studies and all efficacy studies reported reductions in entomological indices. 2 effectiveness studies (using cluster RCT) did not report significant entomological reduction, however control groups had been exposed to some environmental or educational intervention. Lastly, 1 study, looking at entomological and epidemiological data, reported a reduction in entomological indices as well as a lower number of cases of dengue (1 case) in the treated areas against non-treated areas (15 cases). Only English literature was reviewed.