Evaluating alternative insecticides for use in malaria vector control

Abstract

Malaria is a vector-borne disease responsible for morbidity and mortality on a global scale, with particular severity in sub-Saharan Africa. Interventions targeting Anopheles malaria vectors rely heavily on synthetic insecticides. This may select for insecticide resistance in the target population. Exacerbating the resistance problem is the excessive use of the pyrethroid class of insecticide and the limited number of alternatives available for public health use. This raises an urgent need for new alternatives, such as naturally occurring biochemicals, to be investigated. In this study, the larvicidal capabilities of the food spice, black pepper (Piper nigrum), and its principle alkaloid, piperine when administered as a food source to anopheline malaria vector species were evaluated. Additionally, a straight-chain fatty acid mixture patented as “C8910” was also investigated as a larvicide and adulticide against several Anopheles species, with the adulticidal efficacy of C8910 being specifically evaluated against An. arabiensis and a single strain of An. funestus derived from a wild population. The results indicate that black pepper is an effective larvicide when administered as a food source, whereas piperine is not. This suggests that piperine is not the primary larvicidal constituent in black pepper. C8910 demonstrated larvicidal properties, inducing mortality in both An. arabiensis and An. funestus. C8910 was also adulticidal against An. arabiensis and a wild sample of An. funestus. It is concluded that, pending further development and assessment of compliance with WHO standards, black pepper and C8910 could be considered as potential tools for future use in vector control.