Bacillus sphaericus: vector control strategies that produce malaria, yellow fever, and dengue
The increased incidence of diseases of public health such as malaria, dengue and yellow fever associated to side effects of the use of chemical pesticides and the resistance generated has prompted the search for new alternatives for the elimination of its vectors. A viable option is the entomopathogenic bacteria Bacillus sphaericus, first described in 1904 by Neide and Meyer who discovered spore-forming bacteria that exists in nature and is easily grown in vitro and in the body of the larvae.
Its larvicidal activity is due to the production of a crystalline inclusion, called binary toxin A and B of 41.9 and 51.4 kDa, respectively, which, when released in the gut of susceptible insects in their larval stage and after be solubilized by the alkaline pH in the middle portion of the intestine, activate proteases causing dehydration and death of the vectors. It is considered a highly potential and effective larvicide for biological control of Anopheles spp., Aedes spp. and Culex spp. It can be produced commercially by submerged fermentation with small-scale waste protein material. This product has been used and registered in many Latin American countries, where good results were obtained after application.
