# Question regarding blood-sucking insect behavior
**URL:** https://boards.straightdope.com/t/question-regarding-blood-sucking-insect-behavior/956415
**Category:** Factual Questions
**Created:** [December 21, 2021, 1:18pm UTC](https://boards.straightdope.com/t/question-regarding-blood-sucking-insect-behavior/956415 "2021-12-21T13:18:53Z")
**Posts on this page:** 11
**Page:** 1
### Author:  [@Octagon](https://boards.straightdope.com/u/Octagon)
#### Post date: [December 21, 2021, 1:18pm UTC](https://boards.straightdope.com/t/question-regarding-blood-sucking-insect-behavior/956415/1 "2021-12-21T13:18:53Z")
Recently I’ve seen read more reports about blood-sucking insect infestations (“no-see-ums” or biting midges) in the US. There is a lot of quackery when it comes to warding off these types of insects. But I am curious about the predatory nature of these insects. They can follow their ‘prey’ (person) and remain with that ‘prey’ for long periods of time. My question is why? Is it the person’s blood type? sweat composition? hormonal matter? immune deficiency ?Is the problem of being a ‘magnet’ for these insects genetic in nature?
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### Author:  [@Chronos](https://boards.straightdope.com/u/Chronos)
#### Post date: [December 21, 2021, 2:24pm UTC](https://boards.straightdope.com/t/question-regarding-blood-sucking-insect-behavior/956415/2 "2021-12-21T14:24:05Z")
You make it sound like they’re tracking specific individuals, in preference for other individuals. Any evidence for that, as opposed to them just following whatever food source they happen upon until they’re sated?
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### Author:  [@Octagon](https://boards.straightdope.com/u/Octagon)
#### Post date: [December 21, 2021, 2:25pm UTC](https://boards.straightdope.com/t/question-regarding-blood-sucking-insect-behavior/956415/3 "2021-12-21T14:25:32Z")
Sorry Chronos. I do mean 'food source".
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### Author:  [@solost](https://boards.straightdope.com/u/solost)
#### Post date: [December 21, 2021, 4:00pm UTC](https://boards.straightdope.com/t/question-regarding-blood-sucking-insect-behavior/956415/4 "2021-12-21T16:00:34Z")
Speaking for mosquitoes (and I assume this applies to other blood-sucking insects like midges), they are drawn to a variety of chemical attractants. First of all carbon dioxide to detect your presence in the general area, then as they home in on you, they are attracted to chemicals secreting from your skin, like lactic acid.
And some people do seem to ‘smell’ or ‘taste’ better than others, and therefore become more frequent targets, although the exact mechanism why isn’t entirely understood because it involves such a wide cocktail of chemicals. Someone who’s freshly showered and stripped of skin secretions may not be as likely of a target as someone who’s sweaty, or hasn’t showered in awhile. Some people naturally secrete more lactic acid or other good-smelling to a mosquito chemicals than others.
Traditional mosqiito repellents work not by actively repelling mosquitoes but by hiding the natural human odors we generate, making us ‘invisible’ to them. Except for that one area on the back of the neck we left exposed…
> **[Modulation of Host Learning in Aedes aegypti Mosquitoes](https://www.cell.com/current-biology/fulltext/S0960-9822(17)31617-2)**
>
> Mosquitoes show an ability to avoid defensive hosts, but the mechanisms mediating
> these shifts in host preferences are unclear. Vinauger et al. show that Aedes aegypti
> mosquitoes rapidly learn host odors and that learning is dependent on the...
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### Author:  [@mixdenny](https://boards.straightdope.com/u/mixdenny)
#### Post date: [December 21, 2021, 4:34pm UTC](https://boards.straightdope.com/t/question-regarding-blood-sucking-insect-behavior/956415/5 "2021-12-21T16:34:59Z")
Carbon dioxide is one of the main attractants. Those whole yard mosquito vacuums generate CO2 to lure them.
A long time ago when I had carpet in the bedroom and a cat that went outdoors I had a flea infestation. I used to amuse myself by lying on the mattress and gently blowing on the carpet. Any fleas in the area would shoot up to the top of the carpet where I could grab them. You could also hold your arm near the carpet and attract them also.
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### Author:  [@solost](https://boards.straightdope.com/u/solost)
#### Post date: [December 21, 2021, 4:41pm UTC](https://boards.straightdope.com/t/question-regarding-blood-sucking-insect-behavior/956415/6 "2021-12-21T16:41:13Z")
Ticks are attracted to carbon dioxide as well. I heard one experiment you can try if you want to see if a wooded area has a lot of ticks is to put down a square of white poster board on the ground with a chunk of dry ice in the middle. The ticks will gather in a circle around the dry ice like hominids around a monolith.
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### Author:  [@Riemann](https://boards.straightdope.com/u/Riemann)
#### Post date: [December 21, 2021, 5:04pm UTC](https://boards.straightdope.com/t/question-regarding-blood-sucking-insect-behavior/956415/7 "2021-12-21T17:04:34Z")
> [@solost](#):
>
> like hominids around a monolith
I love the simile, but now I’m worried that next year’s ticks will be armed with stone axes and bows and arrows.
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### Author:  [@Chronos](https://boards.straightdope.com/u/Chronos)
#### Post date: [December 21, 2021, 7:35pm UTC](https://boards.straightdope.com/t/question-regarding-blood-sucking-insect-behavior/956415/8 "2021-12-21T19:35:15Z")
Just so long as they don’t get a jump-cut to orbital nuclear weapons.
> [@solost](#):
>
> And some people do seem to ‘smell’ or ‘taste’ better than others, and therefore become more frequent targets, although the exact mechanism why isn’t entirely understood because it involves such a wide cocktail of chemicals.
Heck, it’s hard to even prove that they prefer some people over others. It could be that the people they “don’t like” are getting bitten just as much, but don’t notice it, because they don’t itch from mosquito bites.
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### Author:  [@Hari\_Seldon](https://boards.straightdope.com/u/Hari_Seldon)
#### Post date: [December 21, 2021, 9:28pm UTC](https://boards.straightdope.com/t/question-regarding-blood-sucking-insect-behavior/956415/9 "2021-12-21T21:28:54Z")
My father worked with chemicals (mainly with Nickel sulfate electroplating solution) and claims he never got bit. For three years I worked in a biochem lab and I didn’t get bit either. Since that three year hiatus, I do get bit, but it doesn’t cause any itch. And I do know the difference between that and not getting bit.
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### Author:  [@Ulfreida](https://boards.straightdope.com/u/Ulfreida)
#### Post date: [December 21, 2021, 9:33pm UTC](https://boards.straightdope.com/t/question-regarding-blood-sucking-insect-behavior/956415/10 "2021-12-21T21:33:03Z")
I’m such a mosquito magnet that my family would fight to walk next to me so the mosquitos would be drawn off them.
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### Author:  [@Octagon](https://boards.straightdope.com/u/Octagon)
#### Post date: [December 22, 2021, 6:23pm UTC](https://boards.straightdope.com/t/question-regarding-blood-sucking-insect-behavior/956415/11 "2021-12-22T18:23:55Z")
Thanks Hari\_Seldon,
I wonder if the same is true for people handling synthetic fertilizer.