I am grateful that mosquitoes are not much of a problem in downtown Singapore – perhaps they cannot fly high enough. Their vertical flight range is reported to exceed 21 stories above ground [http://www.nea.gov.sg/cms/sei/ehi1slides.pdf], but I have not seen any at 34 or above.

When traveling, though, it’s a different story! Despite repellent, we end up with all these itchy bumps. Perhaps we could view them as opportunities for mindfulness, but it would be much easier if they would just go away. Is that actually possible?

Long ago, I learned (through a slip of the soldering iron) that heat seems to make the bites disappear as if by magic. To understand why, let’s take a step back.

Blood from injuries generally clots, so the mosquito’s `needle’ would soon become clogged. To prevent that, they inject various proteins with several nasty effects:

– suppressing T-, B-cell and cytokines (immune response)
[http://onlinelibrary.wiley.com/doi/10.1111/j.0141-9838.2004.00712.x/abstract]

– interfering with platelets (blood clotting)
[http://www.jbc.org/content/282/37/26928.full]

– even increasing mortality from West Nile Virus
[http://www.ncbi.nlm.nih.gov/pubmed/23236530]

Yikes! The itching aside, it sure seems useful to undo these effects. We know from basic cooking that (e.g. fish) protein denatures at fairly low temperatures.

Indeed, someone recently asked on reddit [sic] “Can putting a hot spoon on a mesquito bite denature the protien to lessen the allergic reaction”? The replies there seem unnecessarily negative:

“immunoglobulins .. start to denature at around 60C”
Perhaps the ill-posed question led the responder astray, but we are not interested in denaturing the IgG. It suffices to attack the mosquito saliva itself, not our desirable immune reaction to them.

“it would take between less than one to 25 hours (depending on the temperature) to fully denature the antibodies”
In addition to focusing on the wrong protein, this view is overly pessimistic because we do not need to fully and irreversibly denature the protein. Perhaps it is enough to unfold them, which happens more quickly and at lower temperatures.

“alboserpin (the anticoagulant in mosquito saliva that our bodies react to).. are only sensitive to denaturation at temperatures above 60C”
Maybe so, but it actually comprises only 1% of the proteins in mosquito saliva. [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3151045]

“Its remarkable the disinformation regarding this out there; if you think critically about heat-mediated mosquito protein denaturation being the mechanism for itch reduction, it just doesn’t make any sense.”
Sounds like ill-informed and closed-minded dismissal of a valid observation. It is more understandable if coming from a school that claims the only salvation lies in anti-histamines and other drugs. “It is hard to fill a cup which is already full.”

Let’s turn this around and look from the perspective of researchers who want to store mosquito saliva. Potency roughly halves when storing at 21C vs 4C. [http://www.parasitesandvectors.com/content/4/1/33] Sounds potentially useful!

Also, West Nile Virus “is thermolabile and .. inactivated rapidly by heat”. “At 28C the titer of the virus decreased by a factor of 10^3”. [http://www.karger.com/Article/FullText/353698] Very doable. These low temperature thresholds indicate we can measurably reduce mosquito effects at temperatures far short of really hurting our skin. Bring on the heat!

Apparently there is an FDA-approved gadget for the purpose: [http://gizmodo.com/5935350/therapik-bug-bite-relieving-gadget-review-we-cant-believe-this-actually-works] I’ve never tried it, the underside of a mug containing boiled water works well enough. Around 30 seconds seem to do the trick. I’d estimate that temperatures around 45-50C are required.

Please don’t go and get third-degree burns, but some pain is involved.

For completeness, let’s mention the theory that heat merely (temporarily) overloads the nerve that signals itching. That is still possible, but I offer anecdotal evidence that heat-treated mosquito bumps entirely disappear within a few hours, which is not the usual experience.

I hope this helps!