VectoBac 12AS (also known as SC; Suspension Concentrate) is an aqueous suspension formulation of Bacillus thuringiensis subsp. israelensis (strain AM65-52) for control of mosquitoes, black flies, and closely related fly larvae. The product has a potency of 1200 International Toxin Units (ITU) per milligram against Aedes aegyptilarvae.
VectoBac 12AS is intended for use in aqueous spray applications to habitats with little or no vegetation. Rate selected should be based on habitat, larval population/stage, and/or environmental conditions.
VectoBac 12AS is the worldwide standard for biorational control of black fly larvae in rivers. In fact, the particle size and suspension properties of VectoBac 12AS were originally designed for black fly control. In 1974, the World Health Organization
initiated the Onchocerciasis Control Program (OCP) in West Africa to combat the devastating effects of river blindness
(transmitted by black flies) in that region. The introduction of VectoBac 12AS in the 1980s to this program helped the program virtually eradicate the disease, preventing an estimated 600,000 cases of blindness and making 25 million hectares of land safe for use.*
Suggested Rate Range for Black Fly Control:
- Stream/river water (=ppm) for 1 minute exposure time with 0.5–25 mg/liter
- Stream/river water (=ppm) for 10 minutes exposure time with 0.05–2.5 mg/liter
Use higher rate range when stream/river contains high concentration of organic materials, algae, or dense aquatic vegetation. Discharge is a principal factor determining carry of Bti. Use higher rate or increase volume by water dilution in low discharge rivers or streams under low volume (drought) conditions.
VectoBac 12AS is also effective for control of select nuisance flies (Psychoda spp., Chironomus spp.) in sewage facilities utilizing trickling filter systems.
Suggested Rate Range for Filter Fly Control:
Use 10–20 mg/liter; per liter of wastewater feed to the filter per 30 minutes. Use a high rate for control ofChironomus spp. Apply undiluted with pre-calibrated pump or other device into the wastewater feeding into the filters for a period of 30 minutes. Repeat applications as needed after 2–4 weeks. Control ofChironomus spp. may take up to 2 weeks.