Malaria mosquito's odour-sensing systems mapped
Scientists have mapped a sensory organ that the principal malaria-carrying mosquito, Anopheles gambiae, uses to hunt down humans.
They hope this will help in developing better mosquito attractants that will divert them away from humans and reduce the threat of malaria infection.
The findings were published online this week (30 August) in Current Biology.
The sensory organ the scientists investigated — the maxillary palp — is one of the three structures extending from the mosquito's head that together provide the mosquito with a sense of smell and taste.
The researchers believe that the mosquito uses the maxillary palp for long range detection of prey. It uses its proboscis for sensing at close range.
Previous studies on the Aedes aeqypti mosquito, the carrier of dengue and yellow fever, had shown that the maxillary palp contains receptor cells sensitive to carbon dioxide and octenol, chemical signals emitted by humans.
The new research shows that the maxillary palp of A. gambiae is also sensitive to these chemicals, but it contains different receptor cells that make this mosquito sensitive to other human-specific compounds as well.
Lead author Laurence Zwiebel, professor of biological sciences at Vanderbilt University in the United States, told SciDev.Net that they are now in the process of designing new mosquito attractants that will target receptors in A. gambiae's sensory system. These attractants would lure the mosquito into traps, away from their human targets.
Zambia's National Malaria Control Centre coordinator, Elizabeth Chizema, told SciDev.Net, "Any new method that can be used to eliminate malaria is welcome because malaria remains a serious killer disease in Zambia and elsewhere."
The research is part of the Grand Challenges in Global Health Initiative to develop a chemical strategy to prevent the spread of malaria by A. gambiae.
The study involved collaboration of researchers from the Ifakara Health Research and Development Centre in Tanzania, the Medical Research Council Laboratories in Gambia, Vanderbilt and Yale Universities in the United States and Wageningen University in the Netherlands.
Reference: Current Biology doi 10.1016/j.cub.2007.07.062