
Plasmodium-associated changes in human odor attract mosquitoes - tosh
http://www.pnas.org/content/early/2018/04/11/1721610115
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tosh
""" Malaria parasites (Plasmodium) can change the attractiveness of their
vertebrate hosts to Anopheles vectors, leading to a greater number of
vector–host contacts and increased transmission. Indeed, naturally Plasmodium-
infected children have been shown to attract more mosquitoes than parasite-
free children. """

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pygy_
Were those mosquitoes parasite-free?

To maximize infectiousness, the Plasmodii would then manipulate infected
mosquitoes to ignore that smell and feed on uninfected humans...

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tomkinstinch
The community of microbes resident on skin (or rather, their metabolites) has
also been shown to influence attractiveness to mosquitos[1]. Interestingly,
some taxa were associated with decreased attraction, which the authors of the
linked study hypothesize is due to a masking effect. Skin probiotics may be on
the horizon for mosquito deterrence and other applications (think acne,
eczema, etc.). The composition of the skin microbiome is influenced by diet,
host genetics, environment, and other factors (sun exposure, hygeine, etc.).

1\.
[http://journals.plos.org/plosone/article?id=10.1371/journal....](http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0028991)

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car
This company is working on an acne treatment based on bacteria:
[http://www.nakedbiome.com](http://www.nakedbiome.com)

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sschueller
Very interesting

I am a person who mosquitoes love to bite but I don't have any disease (that I
know off). My wife can lay next to me and not get a single bite while I am
fighting them off left and right. I wonder what else can contribute to this
difference.

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fegu
Mosquitoes are attracted to co2. You are probably just bigger than your wife,
exhaling more co2.

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ItsMe000001
That reasoning never quite made sense to me because if that was a or the major
reason, why do I have the signs of unwanted mosquito encounters mostly on or
my feet and ankles?

If that theory indeed is true I think CO2 is just a rough guide to find the
approximate location (within meters) of something alive with blood. I think
once close other guidance systems might take over.

My above opinion isn't worth much, but the CO2 hypothesis seems pretty limited
to me?

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terminado
So, this might be a long shot, but I might hazard a guess that in hot, humid
weather, with stagnant air, the dynamics of where exhaled exhaust goes,
changes.

In the cold, dry air of winter your breath vents upward, but getting near
sunny 90 degree weather, during summer time, it might descend and pool at the
feet of gatherings of people at barbecues.

Carbon dioxide in ambient, matched temperature mixtures tends to be dense, and
sinks toward the floor in many conditions (similarly true for carbon
monoxide), but local conditions obviously vary, and odor travels differently
than entire air masses. If mosquitos are already out, they probably travel
along the odor gradient, toward the most concentrated area of scent.

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ItsMe000001
You assume waaayyyy too much stability for a body of air. The air around you
is moving constantly. Every bit of movement and every tiny heat source causes
movement.

The problem is people don't see "air", but there are ways to visualize it
(e.g. Schlieren photography). Or just watch smoke.

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carapace
"Extended Phenotype" much?

> The Extended Phenotype is a 1982 book by Richard Dawkins, in which the
> author introduced a biological concept of the same name. The main idea is
> that phenotype should not be limited to biological processes such as protein
> biosynthesis or tissue growth, but extended to include all effects that a
> gene has on its environment, inside or outside the body of the individual
> organism.

\----

Totally unrelated mosquito story: A friend of mine told me about a time he was
laying down resting on a hot day with a fan blowing over him to keep
mosquitoes away. He watched a mozzy land in the lee of his body and _walk_
towards him.

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neves
Mosquitos love me, but when I know I'll go to a place with a lot of them, I
start taking B12 vitamin. It was a tip a friend of mine gave me, and it
usually works. I don't know why and never read anything about it.

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CWuestefeld
Sorry to be that guy, but this is probably not true.

 _the notion that ingesting certain products like B vitamins (or garlic, for
that matter) might repel mosquitoes is common, but unfounded. Based on
scientific studies I was able to dig up, B vitamins are not effective mosquito
repellants, and vitamin B12, specifically, is not well-studied.

What scientists know more about is another B vitamin - B1 - also known as
thiamine. As part of a larger survey of effective mosquito repellants, a 2002
study in the New England Journal of Medicine reported that, "No ingested
compound, including garlic and thiamine (vitamin B1), has been found to be
capable of repelling biting arthropods."_ \--
[http://thechart.blogs.cnn.com/2010/07/21/can-
vitamin-b12-pre...](http://thechart.blogs.cnn.com/2010/07/21/can-
vitamin-b12-prevent-mosquito-transmitted-diseases/)

~~~
saltcured
I wonder whether some of these folk remedies might affect the response to
bites, i.e. modulating the immune system response and inflamation...

My wife always claims to be a mosquito magnet, but I have thought about it in
various situations like camping and touring the tropics. I am not sure if she
is getting harassed more than me, or if she just reacts more strongly to all
the bites. Some of my bites are very mild, and I could believe that there
might be more that I don't even notice.

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etiam
I wonder if there are biochemical pathways in, let's say, _Neisseria
gonorrhoeae_ that are actually handy to have in a night on the prowl...

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jraines
I wonder if this is something dogs could be trained to detect.

I used to live near a creek where there were lots of mosquitoes, and when my
roommates and I could go from the car to the house on a bad day, most of us
would get bitten 0-1 times, and one would get bitten 3+

