title: A novel synthetic odorant blend for trapping of malaria and other African mosquito species.
abstract: Estimating the biting fraction of mosquitoes is of critical importance for risk assessment of malaria transmission. Here, we present a novel odor-based tool that has been rigorously assessed in semi-field assays and traditional African villages for estimating the number of mosquitoes that enter houses in search of a blood meal. A standard synthetic blend (SB) consisting of ammonia, (S)-lactic acid, tetradecanoic acid, and carbon dioxide was complemented with isovaleric acid, 4,5 dimethylthiazole, 2-methyl-1-butanol, and 3-methyl-1-butanol in various combinations and concentrations, and tested for attractiveness to the malaria mosquito Anopheles gambiae. Compounds were released through low density polyethylene (LDPE) material or from nylon strips (nylon). Studies were done in a semi-field facility and two traditional villages in western Kenya. The alcohol 3-methyl-1-butanol significantly increased the attraction of SB. The other compounds proved less effective or inhibitory. Tested in a village, 3-methyl-1-butanol, released from LDPE, increased the attraction of SB. Further studies showed a significantly enhanced attraction of adding 3-methyl-1-butanol to SB compared to previously-published attractive blends both under semi-field and village conditions. Other mosquito species with relevance for public health were collected with this blend in significantly higher numbers as well. These results demonstrate the advent of a novel, reliable odor-based sampling tool for the collection of malaria and other mosquitoes. The advantage of this odor-based tool over existing mosquito sampling tools is its reproducibility, objectiveness, and relatively low cost compared to current standards of CDC light traps or the human landing catch.
authors.affiliation: International Centre of Insect Physiology and Ecology, PO Box 30772, GPO Nairobi, Kenya.
authors.forename: Wolfgang R
authors.initials: WR
authors.lastname: Mukabana
authors.forename: Collins K
authors.initials: CK
authors.lastname: Mweresa
authors.forename: Bruno
authors.initials: B
authors.lastname: Otieno
authors.forename: Philemon
authors.initials: P
authors.lastname: Omusula
authors.forename: Renate C
authors.initials: RC
authors.lastname: Smallegange
authors.forename: Joop J A
authors.initials: JJ
authors.lastname: van Loon
authors.forename: Willem
authors.initials: W
authors.lastname: Takken
mesh_terms: D000349:Africa; D000818:Animals; D000852:Anopheles / Q000502:physiology; D000440:Butanols / Q000737:chemistry* / Q000378:metabolism; D009033:Culicidae / Q000502:physiology*; D045782:Hemiterpenes; D006801:Humans; D007306:Insecticides / Q000737:chemistry* / Q000378:metabolism; D009032:Mosquito Control / Q000379:methods*; D009812:Odorants / Q000032:analysis; D010421:Pentanoic Acids / Q000737:chemistry* / Q000378:metabolism; D013844:Thiazoles / Q000737:chemistry* / Q000378:metabolism
chemical_list: D000440:Butanols; D045782:Hemiterpenes; D007306:Insecticides; D010421:Pentanoic Acids; D013844:Thiazoles; C008216:isovaleric acid