News Release

Malaria infection and human attractiveness to mosquitoes

Peer-Reviewed Publication

Proceedings of the National Academy of Sciences

A study uncovers the chemical basis by which human infection with the malarial parasite Plasmodium might lead to increased mosquito bites. To locate hosts, female Anopheles mosquitoes use volatile compounds released from human skin that contribute to body odor. Previous studies have found that Plasmodium infection increases human attractiveness to mosquitoes, but the underlying skin chemistry remained unexplored. Ailie Robinson and colleagues report that in a lab assay Anopheles gambiae mosquitoes were more attracted to the foot odor of children who harbored Plasmodium than to the foot odor of the same children collected 21 days after administration of an antimalarial treatment; foot odors were collected on socks from 5-12-year-old children in western Kenya. In contrast, the mosquitoes did not distinguish between foot odors of parasite-free children collected at the same pair of time points. Chemical analysis revealed that increased amounts of the skin aldehydes heptanal, octanal, and nonanal in infected children were positively linked with parasite density. Mosquito behavioral analysis under controlled conditions suggested that elevated heptanal levels in Plasmodium-infected children might heighten their attractiveness to An. coluzzii mosquitoes. Adding heptanal to a synthetic mosquito lure that mimics healthy human odor failed to increase its attractiveness. However, adding a blend of Plasmodium infection-associated compounds, including heptanal, to this lure, in an attempt to mimic the odor cues of an infected person, proved attractive to An. coluzzii. According to the authors, the findings could illuminate aspects of malaria transmission, help improve the design of mosquito lures, and lead to the development of novel diagnostic biomarkers for malaria.

###

Article #17-21610: "Plasmodium-associated changes in human odor attract mosquitoes," by Ailie Robinson et al.

MEDIA CONTACT: Ailie Robinson, London School of Hygiene and Tropical Medicine, London, UNITED KINGDOM; email: Ailie.Robinson@lshtm.ac.uk


Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.