Summer is finally here – and as temperatures are creeping up, so too are the mosquito bites.
If you’re one of the lucky ones who seems to draw in every one of the little critters, it might feel like life is generally against you.
But fear not: there are several explanations as to why you’re covered in those itchy, swollen lumps and some of your (very smug) friends aren’t.
1. You smell very good to mosquitoes
Dr Christopher Potter, an associate professor of neuroscience at Johns Hopkins University School of Medicine, told The New York Times that your scent can help draw them in – including the odours which are too subtle for humans to detect.
Dr Potter explained: “It’s like strawberries – there’s no one odour in a strawberry that gives it that smell. It’s a combination of a dozen odours that all come together.”
This can include compounds on your skin, from lactic acid and ammonia to a high variety of bacteria.
Sebum, the oily substance meant to help keep our largest organ moisturised, is particularly attractive to mosquitoes. Oh joy.
2. Your blood is especially delicious
The rumours are (partly) true – your blood type also has an impact. Mosquitoes are particularly attracted to people with type O blood compared to those with type A.
A controlled study by the Journal of Medical Entomology found that the secretions we produce usually tell the bugs what your blood type is.
3. Your breathing draws them in
Dr Christopher Bazzoli from the Cleveland Clinic also told the New York Times that your “breathing signature” can help draw in the insects too, as they hunt for CO2.
US-based website Healthline explained: “An increase in carbon dioxide in the air can alert a mosquito that a possible host is close by. The mosquito will then move toward the source of the carbon dioxide.”
That means the more you’re, uh, breathing, like during exercise, the more likely you’ll find yourself covered in little bites.
Healthline also suggested pregnancy may draw in more mosquitoes because those carrying a child release more CO2 and have a higher body temperature.
Jonathan Day, an entomology professor at the University of Florida, previously told HuffPost: “Perhaps CO2 is the most important. The amount of CO2 you produce, like people with high metabolic rates ― genetic, other factors ― increases the amount of carbon dioxide you give off. The more you give off, the more attractive you are to these arthropods.”
4. Your sweat
Lactic acid (released in sweat) is probably a “secondary cue” after CO2, which helps draw the mosquitoes in, according to Day.
It’s particularly attractive to them if it’s been festering on your skin for a bit and is mixed with bacteria.
If you drink alcohol, it can enhance your sweat to the mosquitoes, and your odour.
5. You’re wearing just the right colours
Mosquitoes are drawn to black, dark blue, bright oranges and reds, according to research.
Day told HuffPost: “Mosquitoes have excellent vision, but they fly close to the ground to stay out of the wind.
“They are able to contrast you with the horizon, so how you’re dressed matters. If you have on dark clothes, you are going to attract more because you’ll stand out from the horizon, whereas those wearing light colours won’t as much.”
6. You’re too hot
Healthline pointed out that our bodies give off heat, and female mosquitoes move towards heat sources.
Similarly, Day said body heat is a “tactile cue” which helps keep the bugs on you once all the other factors have attracted them.
The amount of heat you give off tends to vary from person to person, according to genetic differences or physiological differences. Some people are warmer, so they’re more likely to get a bite.
But, what drives mosquitoes away?
While mosquito bites are, mostly, just annoying and itchy, the bugs can sometimes carry serious diseases, so try to repel them when you’re able to.
Try to go perfume free and avoid wearing black, dark blue and bright oranges and reds.
Long sleeves and trousers help too, as do insect repellents – and eating garlic.
Alternatively, you could just get a fan and put it under a table. Associate professor of ecology, evolutionary biology and neuroscience at Princeton University, Dr Lindy McBride, pointed out to the NYT, “they’re not good fliers”.
As they tend to hang around close to the ground and nibble your feet, it’s probably most effective to just point a fan at the ground.