title: Preliminary lack of evidence for simian odour preferences of savanna populations of Anopheles gambiae and other malaria vectors.
abstract: The behavioural response to several culicine and anopheline mosquitoes to the odour of alternative hosts (human vs monkey) arranged in a choice set-up using odour-baited entry traps (OBETs) was assessed in a field experiment in south-eastern Senegal. The experimental protocol followed procedures analogous to those adopted in olfactometer laboratory tests. Two adult Cercopithecus aethiops and a child of similar mass slept inside separate tents and their odours were drawn to each one of two paired OBETs so that approaching mosquitoes could experience both odour-laden streams before "choosing" to fly against one of the two air currents and into the trap. The traps were set up in a riverine forest clearing near the town of Kedougou, where primates (Papio papio, Cercopithecus aethiops, and Erythrocebus patas) are common. A total of 192 mosquitoes belonging to 4 genera was captured during 8 trap nights. All major human malaria vectors including Anopheles gambiae sensu lato, An. funestus, and An. nili, which constituted the bulk of the trap catch (N = 153), clearly expressed a preference for human odour, with > 90% of captured mosquitoes caught in the human-baited trap. A sub-sample of specimens belonging to the An. gambiae complex caught in both traps was identified by rDNA-PCR and RFLP as An. gambiae sensu stricto molecular form S (7/10), and An. arabiensis (3/10). The only species that did not show a preference for the alternative odour-laden air streams, among those caught in significant numbers, were mosquitoes of the genus Mansonia, with both Ma. uniformis and Ma. africana weakly preferring human odour, but not at a statistically significant level. These results are in accordance with the hypothesis that the strongly anthropophilic feeding preferences of An. gambiae did not evolve from an ancestral association with non-human primates.
authors.affiliation: Istituto Pasteur-Fondazione Cenci Bolognetti, Sezione di Parassitologia, Dipartimento di Scienze di Sanità Pubblica, Università di Roma La Sapienza, Italy. carlo.costantini@uniroma1.it
authors.forename: C
authors.initials: C
authors.lastname: Costantini
authors.forename: M
authors.initials: M
authors.lastname: Diallo
mesh_terms: D000330:Aedes / Q000502:physiology; D000818:Animals; D000852:Anopheles / Q000502:physiology*; D005075:Biological Evolution; D002648:Child; D002522:Chlorocebus aethiops / Q000502:physiology*; D003465:Culex / Q000502:physiology; D009033:Culicidae / Q000145:classification / Q000502:physiology; D005247:Feeding Behavior / Q000502:physiology; D006790:Host-Parasite Interactions; D006801:Humans; D007303:Insect Vectors / Q000502:physiology*; D008288:Malaria; D008297:Male; D009812:Odorants; D013045:Species Specificity