This follows with one of the most effective mosquito repellents already in use today. A rotating fan.

It mixes everything in the room around so that the carbon dioxide, sweat, and everything else can't be as easily used to target you.

A good breeze, doesn't have to be that strong, really helps outside.

Also, mosquitoes aren't strong flyers, so they can't get to you if the fan is pushing enough force.

It seems relevant to point out that there are two types of sweat glands [1]. And they secrete different stuff:

"Eccrine sweat is clear, odorless, and is composed of 98–99% water; it also contains NaCl, fatty acids, lactic acid, citric acid, ascorbic acid, urea, and uric acid. Its pH ranges from 4 to 6.8. On the other hand, the apocrine sweat has a pH of 6 to 7.5; it contains water, proteins, carbohydrate waste material, lipids, and steroids. The sweat is oily, cloudy, viscous, and originally odorless; it gains odor upon decomposition by bacteria. Because both apocrine glands and sebaceous glands open into the hair follicle, apocrine sweat is mixed with sebum."

The article mentions acid lactic as a signaling metric. Only the Eccrine glands sweat contains it.

This explains why the no-correlation between strong oddor (casused by the apocrine sweat).

[1] https://en.wikipedia.org/wiki/Sweat_gland

Some east Asian populations have no or almost no odour at all: https://en.wikipedia.org/wiki/ABCC11

It's both interesting and expected that we're only just now really getting a grasp on mosquito targeting. Viruses and bacteria tend to have single targets, easier for us to figure out, whereas more complex mosquitoes logically have more complex targeting systems. We'll probably have it sorted in a decade.

Now, as for my unique anecdotal contribution:

I 1) don't attract many mosquitoes but 2) when one of them does find its way to me, I'm non-reactive (no itchy bump). I'm both a sweaty and oily person, but I don't really produce BO. No stinky armpits (I save a fortune on deodorant), no stinky feet, etc. My father has a similar situation and he's non-attractive for them, but my siblings are less sweaty, but do produce BO and get eaten alive.

> I 1) don't attract many mosquitoes but 2) when one of them does find its way to me, I'm non-reactive (no itchy bump)

There's potential for bias here: (2) might be over-inflating your impression of (1). An alternative hypothesis (not trying to contradict your own experience!): you attract mosquitoes as much as the next person, but since you're nonreactive, you simply don't notice that mosquitoes are bothering you unless you happen to catch them in the act of biting you (which they're good at avoiding), or if you see or hear one flying around you (which could be chalked up to random flight, or them having trouble locating you).

> I'm both a sweaty and oily person, but I don't really produce BO

Another comment on this story (https://news.ycombinator.com/reply?id=19535422&goto=item%3Fi...) points out that mosquitoes home in on lactic acid, which is produced by non-odour-causing eccrine sweat glands, which explains why there is actually no correlation between human-perceptible body odour and mosquito attractiveness.

I am a very sweaty person, and I always get destroyed by mosquitos more than those around me. It's funny how sometimes meaningful research merely confirms things people already believe to be "obvious".

I used to be a very sweaty person, but always had less moquito bites than those around me (though I did have quite a bit if I was alone). So it's far from trivial.

(And preepting the question: I stopped being ultra sweaty after a 20 day water-only fast, never to be sweaty again)

You only had water for 20 days? How do you do that?

People can go without food for a lot longer than they can go without water. 20 days is near the upper end, and not something you should do often, but very much within the normal human limit.

EDIT: s/food/water/

Appetite goes away after 48 hours or so, and then it’s easy until appetite or hunger come back, which take 3-40 days depending on your health, fat reserves, etc.

I had lost my appetite that time, so even first two days were easy.

On phone, so hard to google, but there have been a few we’ll documented cases of people going a whole year with just water, vitamins and ridiculously little protein (losing 100-250 pounds of fat in the process).

Also google valter lungo - fasting 2-3 days at a time is very healthy for you.

For onlookers, https://en.m.wikipedia.org/wiki/Angus_Barbieri's_fast

Small typo: Valter Longo, and you can google Fast-Mimicking Diet (FMD). Highly recommended both as stuff to read, or a 5-day fast to try.

Its quite common with prisoners on hunger strikes. Apparently the feeling of hunger stops after a few days. Have to mention that you should be rather careful with that, the long hunger strikes where people died after month were with a forced feeding tube. With 20 days of total starvation you are already up there.

Refeeding is the dangerous bit, I recall reading. Needs medical supervision, at any rate.

A holocaust survivor once told me her mother died after liberation of the camp by English troops, because they started eating the ample supplies that the guards had kept for themselves. Truly tragic.

> I stopped being ultra sweaty after a 20 day water-only fast, never to be sweaty again

Was that the goal of the fast? And if yes, where did you learn that this works?

No goal. I lost my appetite, and I don’t eat unless I have appetite.

Took about 20 days for it to come back. Actually felt hunger at that point, which is a distinct feeling from appetite - one rarely felt in the 1st world)

I am the same way but I started taking vitamin b1 and that seemed to help me a ton in reducing the number of bites.

What’s your blood type? I have a double trouble situation with being super sweaty and being o negative (which seems to also be an attractant).

I'm facing the same problem & I've heard people talking about certain blood group being more attractive to the mosquitoes;but has this been proven?

The article doesn't mention blood group & specifically mentions that the merit of the research in finding the path i.e. CO2, Odour.

I dont' understand how blood can form path, unless it applies to only second bite i.e. Mosquitoes prefereing individuls with certain blood group after tasting it once.

> I've heard people talking about certain blood group

It's O-type blood that's far more attractive to mosquitos.

I lived in Florida my whole life and have spent a lot of time in tropical places around the world. I do not generally attract mosquitoes, much less than people around me. I have O-type blood.

In the South, we have a saying when you attract them: "You must have that sweet blood"

It's unfortunate that the epistemology of science is such that we can't just take certain things for granted like this, but I understand why it is the way it is. I find psychology research to be particularly guilty of this, so much that in my head I often refer to it as the science of pointing out the obvious.

The thing is that while a lot of things that seem obvious will be confirmed, a lot of seemingly obvious things will turn out to not be true. So we need to apply scientific methods in order to determine which “truths” really are true and which are not. (In cases where the truth is testable — not everything is.)

Beyond that, the fact that they have identified what receptors the mosquitoes use for sensing sweat means, like the article says, that new ways to foil the mosquitoes from sensing humans might be possible to devise in the future.

For psychology, sadly it’s more that researchers are lurred towards seemingly obvious or seducing results.

The reproductibility project was really a god send in this respect: https://osf.io/ezcuj/

I am a very sweaty person and mosquitos do not touch me. When other people suffer, I usually did not even notice there are any mosquitos around at all. So not that obvious for me.

Can you share your blood type? I’m o neg, of the sweaty persuasion, and get destroyed by the buggers. My father in law is AB, is probably normal on the sweat spectrum, smokes and mosquitoes don’t bug him.

I'm a sweaty dude and I'm also O-. I very rarely ever notice mosquitoes around and maybe contend with 2-3 bites a year. My wife is an A type, who doesn't sweat profusely, but she is harassed by mosquitoes every year. She gets it really bad, to the point where we're both actively trying to defend her against them with sprays and portable fans when we're out hiking or backpacking, etc...

While outcomes may be obvious, mechanisms are seldom obvious. Understanding mechanisms often helps us discover new outcomes that weren't so obvious before.

I don't buy it. I'm not sweaty at all and mosquitos always 'liked' me more than those around me.

Everybody sweats, you too. I don't think you need to be very sweaty to attract mosquitos, but everybody's sweat is different so that likely plays a role.

So can we now build a decoy that emits CO2, human sweat odour, and heat, that traps and kills mosquitos?

Here's a product I found awhile back: http://www.mosquitomagnet.com/

Yeah, I found that product shortly after moving to Thailand. Unfortunately, the price in Thailand is many times the price shown on their website, over US$1,000. Here for example https://shopee.co.th/BlackHole-%E0%B9%80%E0%B8%84%E0%B8%A3%E...

That's the cheapest I have seen it in Thailand and at 39,000 Thai baht that is more than US$1,200.

We can just as easily build a drone that senses CO2, humans sweat odour and heat, that kills humans.

I’d suggest that may cause some legal difficulties.

Or military interest.

It could also lend itself to a new interpretation of the term SWATing.

A mosquito carrying a deadly disease is already this, and self-replicating too.

Probably explains why (anecdotally) white vinegar is so effective at repelling mosquitos.

This makes sense. I use white vinegar to treat a skin disease. It changes the acidity of your sweat, which then affects what bacteria can flourish on your skin. It's the bacteria that produce the smell.

Read the article – it's bacteria that produce the smell humans perceive as "sweaty", but it's not that smell that attracts the mosquitoes, but rather acidic compounds that are already present in our sweat.

Any reason why some people seem to attract mosquitos more than others? Is it really just sweatiness or something else in a person's blood or scent?

I am not convinced it is just sweat. But it may be a contributing factor.

My father grew up on a farm in a part of the world with a lot of mosquitos. He says he would work in the fields all summer shirtless and never even notice any mosquitos.

I hate going there in the summer because of the little bastards. (And the horseflies, I really hate them).

Wind forward 50 years of mostly city living in other parts of the world, and whenever he flies back to his childhood home for a few weeks holiday he gets eaten alive.

His blood type has not changed. He may be more sweaty as he is a little chubbier, but he was probably quite sweaty working in the fields as a kid as well.

I suspect it has to do with lifestyle. For him (and me) mostly working in office environments for most of the year for many years, makes your skin/odour/heat different than if you were an outdoorsy person that has a more hardened skin that is less attractive to mossies. Perhaps.

That said I don't really hear of anyone that lives in the mosquito heavy area that is susceptible to them whether they are office or farm people. Only outsiders. That may be self-selecting as they would move away though.

Diets have changed considerably since then too

I saw a video on youtube that said theres 4 or so genes that have an effect on your attractiveness to mosquitos.

This might be a great opportunity to try to understand why Avon Skin-so-Soft functions as an effective repellent when other purpose-developed products fail. Perhaps looking closely at the components in the SsS mix to see which masks the lactic acid signal would be a good place to start.

I know a guy that has a small DNA mutation.

Musquittos died when bit him ( his parents have it to). I haven't seen it in real life, but he was an honest it guy. So I give him the benefit of the doubt

It is understood from this these animals are created for biting human beings and sucking from our body. Maybe there are some benefits we may does not know

Sounds like a naturalistic fallacy and/or a just world fallacy.

There's not a silver lining to everything. Some things just suck. Nature is brutal, not caring. Many relationships between organisms are purely parasitic, exploitative, not symbiotic. If you really want a downer, look up what some varieties of the cordyceps parasitic fungus do to ants.

For anyone else not familiar with cordyceps fungi, here's a three-minute clip from BCC Planet Earth: https://www.youtube.com/watch?v=XuKjBIBBAL8

Not humans specifically but any warm blooded animal. The only benefits likely are to the insect (not animal) itself.

Mosquitos kill more humans than any other animal