Abstract
The malaria mosquito Anopheles gambiae sensu stricto is mainly guided by human odour components to find its blood host. Skin bacteria play an important role in the production of human body odour and when grown in vitro, skin bacteria produce volatiles that are attractive to A. gambiae. The role of single skin bacterial species in the production of volatiles that mediate the host-seeking behaviour of mosquitoes has remained largely unknown and is the subject of the present study. Headspace samples were taken to identify volatiles that mediate this behaviour. These volatiles could be used as mosquito attractants or repellents. Five commonly occurring species of skin bacteria were tested in an olfactometer for the production of volatiles that attract A. gambiae. Odour blends produced by some bacterial species were more attractive than blends produced by other species. In contrast to odours from the other bacterial species tested, odours produced by Pseudomonas aeruginosa were not attractive to A. gambiae. Headspace analysis of bacterial volatiles in combination with behavioural assays led to the identification of six compounds that elicited a behavioural effect in A. gambiae. Our results provide, to our knowledge, the first evidence for a role of selected bacterial species, common on the human skin, in determining the attractiveness of humans to malaria mosquitoes. This information will be used in the further development of a blend of semiochemicals for the manipulation of mosquito behaviour.
Highlights
The African malaria mosquito Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) is one of the most important malaria vectors because of its preference to feed on humans [1]
No preference of A. gambiae was found for trapping devices baited with bacteria at the time of exponential growth compared to trapping devices baited with standard medium alone (Figure 2; x2-test, d.f. = 1, P.0.05), except for trapping devices baited with S. epidermidis which caught significantly fewer mosquitoes than medium alone (Figure 2; x2-test, d.f. = 1, P = 0.034)
Four of the five bacterial species grown in vitro in liquid medium, produced volatiles that were attractive to the malaria mosquito A. gambiae at the concentrations tested (Figure 2)
Summary
The African malaria mosquito Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) ( termed A. gambiae) is one of the most important malaria vectors because of its preference to feed on humans [1]. This mosquito species is nocturnal and is mainly guided by body odour to find its host [1]. Several volatile compounds that mediate host-seeking behaviour in mosquitoes have already been identified and tested in laboratory, semi-field or field studies. The factors determining the quantity of compounds and composition of the odour blend released from the human skin that mediate mosquito behaviour have received little attention
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.