Abstract

Malaria fever is a major disease that has killed millions of people in tropical and subtropical regions of the world. Mosquitoes are vectors of this debilitating and fatal disease. Therefore, mosquito control becomes paramount using environmentally friendly biological agents instead of chemicals. Water samples obtained from the gutters and water logged areas and soil samples analyzed resulted in 18 different bacteria isolates identified as Staphylococcus sp., Streptococcus sp., Shigella sp., Salmonella sp., Kiebsiella sp., Micrococcus sp., Escherichia coli, Pseudomonas sp., Proteus vulgaris, Proteus penneri, Bacillus sp., Serratia sp., Sporolactobacillus sp., Listeria sp., Clostridium sp., Lactobacillus sp., Enterococcus sp and Citrobacter sp. The activities of these bacteria against 8 day old mosquito larva at different concentrations and volumes were determined. At the end of the screening period of 7 days with bacteria concentration of 3.0 x 10⁸ cfu/ml, Bacillus sp. showed 80% activity, Clostridium sp. 50% activity, Proteus vulgaris and Proteus penneri 20% activity each against the mosquito larva. At bacteria concentration of 3.0 x 10⁹ cfu/10 ml, the activities of the bacteria against the mosquito larva were Bacillus sp. 100%, Clostridium sp. 85%, Sporolactobacillus sp. 60%, while Proteus vulgari and Proteus penneri 40% each. Lactobacillus sp had 35% activity. The rest of the bacteria isolates had no activity or insignificant activities. Other than Bacillus sp which is a known bioinsecticide, Clostridium sp. and Sporolactobacillus sp. can be genetically modified to be used as bioinsectides as man continues to search for alternative means of combating mosquito borne diseases.

Key words: Larvicide, larva, gutters, mosquito, vectors, activity.