Field efficacy of thermally expelled or live potted repellent plants against African malaria vectors in western Kenya

Abstract

Summaryobjective To estimate the effectiveness of live potted plants and thermal expulsion of plant materials in repelling African malaria vectors in traditional houses in western Kenya.methods Ocimum americanum, Lantana camara and Lippia ukambensis were tested in live, intact potted form whereas leaves of Corymbia citriodora, leaves and seeds of O. kilimandscharicum and O. suave were tested by thermal expulsion from modified traditional stoves. A latin square design was applied for randomly assigning the treatment and control plants to experimental houses over different nights.results All plant species showed significant repellency against Anopheles gambiae sensu lato Giles (Diptera: Culicidae) (81.5% An. arabiensis Patton and 18.5% An. gambiae sensu stricto Giles), the main vectors of malaria in Africa, with the highest repellency by C. citriodora (48.71%, P < 0.0001) followed by an equal level of repellency of O. kilimandscharicum and O. suave (44.54%, P ¼ 0.001) during application of plant material by thermal expulsion. All three plant species also showed a residual effect against An. gambiae s.l. with 36-44% repellency post-application period (22.30-06.30 hours) after a period of thermal expulsion. Similarly, intact potted plants of O. americanum and L. camara repelled An. gambiae s.l. significantly (37.91%, P ¼ 0.004; and 27.22%, P ¼ 0.05, respectively). Thermal expulsion of leaves and seeds of O. kilimandscharicum significantly repelled An. funestus Giles, although none of the potted plants repelled this species.conclusion Both methods of application may offer cost-effective alternatives as additional means of household protection, and a useful complement to bed nets, particularly for the early part of the evening before bedtime.

Enhancing Malaria Prevention in Cameroon Through Community Participation: An in-Depth Review

“…[57] Similar studies have been reported in Kenya [56,58] and soap-form ("Faso Soap") repellents has also proven effective in Burkina Faso. [59] Although, rural communities have the skills to prepare, it is considered laborious, [56] making it less organisationally feasible. It is also considered old-fashioned, stains dresses, has bad odour [57] and promotes gender inequity because the burden to prepare is often on the women, hence, unacceptable.…”

“…[57] Mosquitoes do not bite 52% and 39% of those who use Saccharum officinarum and Ocimum basilicum (traditional plant repellents) respectively in Cameroon. [57] Similar studies have been reported in Kenya [56,58] and soap-form ("Faso Soap") repellents has also proven effective in Burkina Faso. [59] Although, rural communities have the skills to prepare, it is considered laborious, [56] making it less organisationally feasible.…”

“…[56] This requires the use of repellents but modern types like diethyltoluamide are ineffective, unavailable and unaffordable particularly in the rural areas where they are most needed. This has caused many to resort to using local plant repellents.…”

Chemical Defenses in Eucalyptus Species: A Sustainable Strategy Based on Antique Knowledge to Diminish Agrochemical Dependency

“…Lucia et al (2007) have also demonstrated that E. globulus essential oil displays toxic effects on Aedes aegypti larvae, these authors determined its LC 50 =32.4 ppm. In relation to this activity, Seyoum et al (2003) have reported that burning of E. citriodora leaves represents a cheap and effective method of household protection against mosquitoes in Africa.…”

Chemical&nbsp;Variability and&nbsp;Biological Activities of&nbsp;<em>Eucalyptus</em> spp. Essential Oils

“…citriodora leaves has been traditionally used as insecticide repellent, especially by low income families to protect them against mosquitoes [212].…”