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.
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?
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.
The problem is people don't see "air", but there are ways to visualize it (e.g. Schlieren photography). Or just watch smoke.
"Both Aedes aegypti and Anopheles gambiae mosquitoes — which transmitdengue and malaria respectively — were much less attracted to the scented beads after being exposed to the chemical. These results showed that the receptor responsible for detecting carbon dioxide also detects skin odorants."
https://www.nih.gov/news-events/nih-research-matters/how-mos...
And thermal features:
http://www.caltech.edu/news/mosquitoes-use-smell-see-their-h...
[1] https://veritasium.com/education/why-are-mosquitoes-attracte...
This seems more probable than increased amounts of CO2 floating around your feet and ankles, especially if you are laying next to you wife where the aggregate CO2 from both of you breathing will be distributed fairly evenly between you.
A quote from tomkinistinch's linked article: "...washing the feet with a bactericidal soap significantly alters the selection of biting sites...".
I wish we were at a point technologically where it would be simple(and cheap) for a person to detect and catalog things like VOCs that skin bacteria produce, or quantities of bacteria on the skin to determine how they correlate with something like mosquito attraction.
It would be pretty great to be able to say definitively that x bacteria concentrations on your skin are attracting mosquitoes to you, rather than simply conceding "mosquitoes love to bite me".
I believe different attractors are weighted more strongly in different types of mosquitoes too. Some prefer co2, some heat, other detect compounds in sweat or exhaled gases, like the aldehydes from bananas!