Scientists have discovered that one malaria causing parasite Plasmodium falciparum produces chemical compounds called terpenes. Terpenes are a large and diverse class of organic compounds. In the chemical industry, they are the major components of resin, and of turpentine produced from resin.
These chemicals are key to producing the odors that attract mosquitoes. These chemicals have been detected in the sweat and breath of people who have malaria.
The researchers detected the chemical traces by infecting human blood cells with the parasites and holding them, with growth media, in air-tight bags. The gas produced by the respirating cells was then sampled and send for chemical analysis.
Further investigation showed that the parasite uses a chemical pathway (termed MEP) to produce the terpenes. Two terpenes were dominant: one called limonene (which has a slight lemon-y smell) and pinanediol (which has a slight pine-like odor). These smells appeal to mosquitoes and the insects are equipped to pick these out from distance.
It is hoped that the discovery will lead to the development of a breathalyzer test to determine if someone has malaria. Such tests would be far easier, and more pleasant for the patient to endure, than a blood test.
The information should also help scientists to understand why one person becomes infected with malaria and another does not, or why some people are more prone to being bitten by mosquitoes that others.
The research has been published in the journal mBio. The paper is titled “Malaria Parasites Produce Volatile Mosquito Attractants.”
In related news, mosquitoes carrying “tropical diseases” could become widespread across the U.K. over the next 20 or 30 years. This is assuming that European temperatures continue to rise.
