Study suggests that shirt colour could be the key to scaring away mosquitoes

The start of summer brings with it many fond memories. Summer holidays, trips to the beach, long walks in the countryside; but unfortunately all of these idyllic pursuits can be ruined by the involvement of an unwelcome guest.

Mosquitoes carry a painful bite and often leave their victims with red, itchy scars. Worst still, numerous diseases and viruses are carried by the winged insects, meaning that they are definitely best avoided.

Fortunately a new study from the University of Washington claims to have uncovered the secret: wearing cooler colours.

Researchers found that a species of common mosquito is more likely to be attracted to red or orange colours because they are closer to colour emitted by human skin. At the other end of the spectrum, mosquitos typically ignore cooler shades of green, blue, purple and white.

Avoid red clothes to steer clear of mosquito bites

The study, entitled ‘The olfactory gating of visual preferences to human skin and visible spectra in mosquitoes’, tracks a number of factors related to how mosquitos choose hosts and mates. In the written abstract, researchers concluded:

“Sensitivity to orange and red correlates with mosquitoes’ strong attraction to the colour spectrum of human skin, which is dominated by these wavelengths.”

The study was carried out with the use of a real-time 3D tracking system to quantify the behaviour of more than 1.3 million mosquito trajectories. It was carried out in a wind tunnel so scientists were able to control factors that could influence mosquito decision-making.

Professor explains Washington study

Jeffrey Riffell, professor of biology at the University of Washington, explains that previously it had been thought that the three factors attracting mosquitoes were breath, sweat and the temperature of skin. However his team were able to add colour to the list of things that can make you stand out to a mosquito.

“In this study, we found a fourth cue: the colour red, which can not only be found on your clothes, but is also found in everyone’s skin,” he said. “The shade of your skin doesn’t matter, we are all giving off a strong red signature. Wearing clothes that avoid those colours, could be another way to prevent a mosquito biting.”

One other important conclusion drawn from the study was the impact that odour has on mosquitoes’ behaviour. They found that without any odour stimulus (recreating the CO2 produced by humans and other animals) mosquitoes largely ignored all colours. However once a small amount of CO2 was added to the wind tunnel the mosquitoes were far more drawn to red, orange and black objects.