If you’re like me, approach these late afternoon summer outdoor gatherings with fear.
After all, if there are mozzies around, they will be before everyone else. It will be you who clap and scratch your skin while others enjoy their gin and tonic undisturbed.
“But why me?” I hear you moan.
It’s not for a lack of experimentation, but scientists still don’t definitely know the answer to it – though they think it’s probably more than one thing.
And they did some neat experiments on behalf of science to answer the question.
Dirty socks and Limburg cheese provide clues
Did you know that scientists tested the taste of mosquitoes in cheese and found that some types love the smell of blue cheese while others prefer Limburgers?
Some think that Limburg cheese smells like dirty socks. (Getty Images: PicturePartners)
In fact, the US entomologist Dan Kline took up this idea back in the 1990s when he was visited by European colleagues who gave Limburg cheese as presents.
“It smelled like dirty socks to me,” says Dr. Kline from the Florida Department of Agriculture Research Center.
One day in the laboratory he was “particularly bored” because the mosquitoes were not attracted to any of the scents he presented them.
So Dr. Kline off his stinking socks – which he had been wearing for four days – and presented them to the insects.
“That was the best response we’ve ever seen.”
Experiments with smelly socks provide clues about the types of chemicals that attract mosquitoes.Getty Images: rudigobbo)
It turns out that Limburg cheese contains bacteria similar to that between our toes – a fact that has not escaped the notice of the monks who originally developed the cheese, says Dr. Kline.
“The monks used their feet to make this cheese. The toe bacteria were involved in the production of Limburg cheese. “
The “smell” of your skin
While experimenting with dirty socks is not Dr. Kline, however, has highlighted the fact that mosquitoes are attracted to volatile chemicals that we exhale or that are produced by bacteria that act on substances produced on the skin, including sweat.
And some volatile chemicals that humans give off actually seem to protect them from mosquitos.
Dan Kline has spent his entire life studying mosquitoes and what attracts them. (Shipped: USDA)
Interestingly, a colleague of Dr. Kline appeared to be immune to mosquito bites, and an analysis of her skin odors revealed that she was emitting relatively high levels of a chemical that blocked the mosquito’s sense of smell.
“Your ratio of this compound to other compounds was higher,” says Dr. Kline.
Findings like this are tempting in terms of developing the ultimate natural mosquito repellent.
But there are no easy answers here.
Carbon dioxide and body heat
Even before they even get close to your skin, mosquitoes are attracted to the exhaled carbon dioxide – something they can see at least 10 meters away. Your body heat also helps the mosquitoes zoom in on you.
“A complex interplay of all these indications decides whether you will be bitten,” says Dr. Kline’s fellow chemist Ed Norris.
Differences in our genetics and the cosmetic products we wear also contribute, making it a very difficult task figuring out what exactly makes someone a Mozzie magnet.
There are some logical reasons why pregnant women are more attracted to mosquitos than others, but this is not something that can be taken for granted.Unsplash: Xavier Mouton Photography)
In addition, different mosquitoes prefer different smells.
“There are many mosquitos that are known to bite the ankle or face, so there are likely to be different volatiles on these different parts of the body that attract them,” says Dr. Norris.
Finally, your skin’s tendency to respond to bites can also explain why some people carelessly enjoy that outdoor party while you aren’t.
You may get bitten, but you won’t even notice!
Does Eating Bananas / Garlic / Vitamin B Make A Difference?
Even so, many of us love a simple explanation – and the promise of a more pleasant alternative to smearing insect repellent – so it’s no wonder there are so many theories claiming why some people prefer mozzies over others.
For example, you may have heard that eating bananas or drinking beer attracts mozzies, while eating garlic or vitamin B protects you.
Drinking beer is said to attract mosquitos, but experts say there is no convincing evidence. (ABC News: Thea Halpin)
Unfortunately, says Cameron Webb, a medical entomologist at the University of Sydney, none of these ideas are worth hanging on to.
“While some foods or drinks can subtle changes in mosquito attractiveness, changing your diet won’t stop you from using insect repellants,” says Dr. Webb.
There is some evidence that people with certain blood types are more attractive to mozzies, but Dr. Kline says there is conflicting evidence and not enough research to clarify the question.
Are bananas an attractant for mosquitoes? Experts don’t believe. (Pixabay: Alice)
And are men or women bitten more often? It depends on.
“Usually males tend to have more volatiles on their skin that attract mosquitoes, but it’s hard to generalize,” says Dr. Norris.
There are also studies that suggest that pregnant women are more likely to be bitten.
This could be because they produce more CO2 and have higher temperatures in the late stages of pregnancy, which can result in more volatiles being released from their skin.
Take your courage, not all mozzies are after you
While mosquito-borne diseases are a problem, some species of mosquitoes don’t even bite humans.
Some prefer to bite animals like frogs, snakes, birds or even leeches.
And the really good news is that there are small numbers of mosquitos that don’t suck blood at all.
Dr. Webb points out the giant Toxorhynchites speciosus, which has a wingspan of 10 millimeters.
A giant Toxorhynchites-tessspillekom mosquito. (Delivered: Cameron Webb)
“Stretched out from the end of your legs to the tip of your trunk, it would be almost 30 mm.”
The females of species of mosquito that bite us depend on blood to develop their eggs, but the females of this giant species get their protein by eating the larvae of other mosquitoes.
“They are as good as no mosquitoes,” says Dr. Webb.
How to avoid mosquito bites
Cover with long sleeves, pants and covered shoes
Use DEET, picaridin, and oil eucalyptus repellents (essential oils and other herbal products will need to be reapplied more often)
Citronella sticks and candles can help, but only if you sit nearby
Sit near fans – mosquitoes can’t fly in the wind
Don’t worry about sonic devices or repellent wristbands as these are generally pretty useless
Remove stagnant water in everything from gutters to trays for potted plants – mosquitoes only need about a milliliter of water to reproduce
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