Enhancing Attraction of African Malaria Vectors to a Synthetic Odor Blend

Abstract

The deployment of odor-baited tools for sampling and controlling malaria vectors is limited by a lack of potent synthetic mosquito attractants. A synthetic mixture of chemical compounds referred to as "the Mbita blend" (MB) was shown to attract as many host-seeking malaria mosquitoes as attracted to human subjects. We hypothesized that this effect could be enhanced by adding one or more attractive compounds to the blend. We tested changes in the capability of MB (ammonia + L-lactic acid + tetradecanoic acid +3-methyl-1-butanol + carbon dioxide) to attract host-seeking malaria mosquitoes by addition of selected dilutions of butyl-2-methylbutanoate (1:10,000), 2-pentadecanone (1:100), 1-dodecanol (1:10,000), and butan-1-amine (1:10,000,000). The experiments were conducted in semi-field enclosures and in a village in western Kenya. In semi-field enclosures, the attraction of Anopheles gambiae sensu stricto females to MB-baited traps was not enhanced by adding butyl-2-methylbutanoate. There was, however, an increase in the proportion of An. gambiae caught in traps containing MB augmented with the selected dilutions of butan-1-amine, 2-pentadecanone, and 1-dodecanol. When tested in the village, addition of butan-1-amine to MB enhanced catches of female An. gambiae sensu lato, An. funestus, and Culex mosquitoes. 1-Dodecanol increased attraction of An. gambiae s.l. to the MB, while addition of 2-pentadecanone improved trap catches of An. funestus and Culex mosquitoes. This study demonstrates the possibility of enhancing synthetic odor blends for trapping the malarial mosquitoes An. gambiae s.l. and An. funestus, as well as some culicine species. The findings provide promising results for the optimization and utilization of synthetic attractants for sampling and controlling major disease vectors.

Controlling mosquitoes with semiochemicals: a review

“…triseriatus -p-Cresol [37,40] CO 2 [11,19,61] o-Cresol [40] 1-Octen-3-ol [11] 4-Methylcyclohexanol [40] 2,4-Dimethylphenol [40] 2,3-Dimethylphenol [40] 4-Ethylphenol [40] An. [11,19,61] Hexanal [94] Cedrol [46] Octanal [113] β-Pinene [94] Decanal [113] Limonene [94] 2-Nonanone [113] β-Ocimene [94] Benzothiazole [113] (E)-Linalool oxide [94] 2-[(2-Ethylhexyl)oxy]-ethanol [113] (E)-β-Farnesene [94] 5-Compound blend with butan-1-amine, 2-pentadecanone and 1-dodecanol [114] 3-Compound blend: (E)-linalool oxide, β-pinene, β-ocimene [115] (E)-3-Methyl-2-hexenoic acid [84] (Z)-3-Methyl-2-hexenoic acid [84] Sesquiterpenes and alkenes [104] 7-Octenoic acid [84] Acetone [11] Lactic acid [11]/(S)-lactic acid [9,19] 1-Octen-3-ol [11] 4-Methylphenol [11] Aliphatic carboxylic acids [11] Carboxylic acids [9] Ammonia [9] 3-Compound blend: ammonia, [11,19,61] -Dimethyl trisulfide (DMTS) …”

Optimisation and field validation of odour-baited traps for surveillance of Aedes aegypti adults in Paramaribo, Suriname

“…The skin or bacteria on the skin excrete these odour cues that guide mosquitoes to their host [15]. Several studies resulted in the production of synthetic blends that attract as many mosquitoes as, and sometimes even more mosquitoes than human odour [16][17][18][19]. As a result of these studies, the 'Mbita blend' (also known as the MB5 blend) was developed, consisting of five different volatile compounds: lactic acid, ammonia, tetradecanoic acid, 3-methyl-1-butanol and butan-1-amine [19,20].…”

“…Several studies resulted in the production of synthetic blends that attract as many mosquitoes as, and sometimes even more mosquitoes than human odour [16][17][18][19]. As a result of these studies, the 'Mbita blend' (also known as the MB5 blend) was developed, consisting of five different volatile compounds: lactic acid, ammonia, tetradecanoic acid, 3-methyl-1-butanol and butan-1-amine [19,20]. The MB5 blend has been developed and optimised for attracting African anthropophilic Anopheles mosquitoes towards the BG-Suna trap [16,19,21,22].…”

“…As a result of these studies, the 'Mbita blend' (also known as the MB5 blend) was developed, consisting of five different volatile compounds: lactic acid, ammonia, tetradecanoic acid, 3-methyl-1-butanol and butan-1-amine [19,20]. The MB5 blend has been developed and optimised for attracting African anthropophilic Anopheles mosquitoes towards the BG-Suna trap [16,19,21,22]. Interestingly, the blend, when combined with CO 2 , also effectively caught Ae.…”

Caracterização do perfil de compostos orgânicos voláteis produzidos por cultura de células e animais infectados com <i>Leishmania infantum</i>

“…do mosquito A. gambiae, vetor da malária(Mweresa et al, 2016).Portanto, é possível supor que esse composto também possa atuar em conjunto com outros na atração de vetores, tais como o da Leishmania, apesar desse parasito não aumentar a sua produção durante a infecção.Outro composto com perfil semelhante ao 1-dodecanol e pertencente à classe dos hidrocarbonetos é o 3-metileno heptano, sendo encontrado em maior quantidade nas culturas de leucócitos infectadas ou não. Este resultado mostra que a infecção não altera a liberação deste composto e que sua fonte provável são as células mononucleares.Entretanto, não é possível dizer se esse composto atua ou não na atração de vetores devido à ausência de estudos sobre ele na literatura.…”