Why do some people get bitten by mosquitoes and not others?

DSC00544Are you one of those people that always gets bitten by a mosquito or maybe you are one of the lucky 20% who rarely receive a bite?  This article will explain why; drawing on the latest scientific research in an easy to digest format.

With over 200 million insects for each and everyone of us, this is worth knowing….

Firstly, lets look at how a female (they are the only ones to bite – the males feed off nectar) mosquito locates a blood meal in the first place.

All humans emit kairomones common ones include CO2 and lactic acid, around 48 have been identified so far.  It is thought that different species of mosquito prefer different kairomones, in the same way as some people prefer spicy and others don’t.  All of us have our own kairomone ‘signature” which is probably unique in the same way as a fingerprint.

Therefore, anyone who is breathing will draw female mosquitoes towards them.  So why do those lucky 20% not get bitten?
It has been demonstrated that these people have certain chemicals in their blood, sweat and tears that repels mosquitoes making them unattractive.  Some of these naturally produced molecules may also be masking individual kairomones, in the same way as incognito anti-mosquito spray camouflages users.

If you are a mosquito magnet and happen to be around someone who rarely gets attacked, you are more likely to get eaten alive because they will be attracting their share of insects into your space, along with your mighty portion of  mozzies, it means you are going to be the main meal of the day!

So what can you do to make yourself less attractive to insects?

Well, anything that cuts down on your kairomone emissions is an excellent start. For example, putting your dirty laundry in an air-tight carrier bag whilst travelling.

Certain groups of people are particularly attractive to blood sucking beasties, like fair skinned females and those of a large disposition – because of the greater surface area of skin cells; more kairomones are emitted.

According to Dr Nigel Hill (who regrettably recently passed away this month), from the London School of Hygiene and Tropical Medicine, simply washing properly will reduce your kairomone output by around half.  To wash properly means to exfoliate your skin every couple of days and use soaps and other washing products that don’t smell attractive to biting insects – which is pretty much most products on the market.  Instead you need to be using at the very least unscented items or better, a citronella, tea tree, or lemon eucalyptus scented – these all offer a level of protection.  Also be aware of the scent of your clothes after washing.  To deal with the remaining kairomones you either need to physically block or stop the mosquito biting you by using for example, an impregnated mosquito net which is quite impractical on the move.  Or use a camouflage spray like incognito or last and least favoured, because of the risk using toxic chemicals, a good repellent.  Apart from the health and environmental risks, more people are now getting bitten whilst wearing toxic repellents such as Deet; possibly because mosquitoes have associated the repellent smell with the fact that food lies underneath – just like Pavlov’s dogs did with a bell – so they make a concerted effort to find a tiny spot of skin that hasn’t got any on.  They also adopt alternative strategies, such as biting though your clothes – she can even feed through jeans!  In short if they know you are there, the vampire-like insects are not going to stop trying to suck your blood until they’re dead.

In conclusion, there are many different things you can do to avoid getting bitten, it just depends on how badly you want to! You can read other articles on this blog to help you.

You need to try different options and find out what works well for you, what works for Jack won’t necessarily work for Jill.

With a bit of application it is possible to avoid all bites.

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