You mentioned treating infections with heat recently- how does that work?
There are two ways we use heat to treat skin infections.
Today, in a hospital setting, something called "warm compresses" are generally used when treating something like an abscess (a pocket of pus below the skin). The procedure for this is generally to take a chemical hot pack, crack it, wrap it in a moist wash cloth, and place it over the site of the abscess. This is replaced maybe once per hour, if the nurse has time.
Generally, this is done in addition to IV antibiotics. The idea is that the warm pack softens skin around the pus pocket, letting it break through and drain. The antibiotics prevent the infection from spreading, and once the buildup of pus is gone, the antibiotics take care of the remaining infection.
Prior to antibiotics (and coming back soon if we end up in a post-antibiotic era), they would use hot compresses instead.
Hot compresses are different.
Hot compresses can be used with or without antibiotics. They are a good first line treatment if you can catch a skin infection early. They area great for small areas of cellulitis, abscesses, and small-medium cuts and scrapes with signs of mild-moderate infection (some redness, swelling, drainage, and pain around the injury- though definitely ask a doctor first if you have streaks coming from the wound or have a fever).
For a hot compress, you want to get 2-3 clean cotton rags. Set them in some near-boiling water. Fish one of them out with a fork, let it cool, dripping over the pot until it is just bearable on skin. You don't want it to burn, but you also don't want it comfortable. Think 106-110F. Fold it and hold it against the site of the infection. You may need to hold a folded dry cloth on top of the wet one due to the heat.
It will hurt at first. If it doesn't, the rags are too cool.
When that first one stops hurting, put that one back in the water and fish the next one out, and repeat the process. After about 5-10 minutes you'll notice that even though the rags are just as hot as they were before, they no longer hurt when they are placed on the skin. The area will look red. Do this for about 20-30 minutes with as few interruptions as possible, then let the site cool. Do this 4-5 times per day until the infection goes away.
This works for two reasons. Reason one is that in order to fight an infection, blood needs to be able to get to the area to bring white blood cells and remove waste and dead cells. Sometimes normal blood flow doesn't allow this to happen efficiently enough to treat the infection. Applying heat widens blood vessels, temporarily increasing blood flow to the area and allowing more immune cells to do their job. If you're on an antibiotic, this also allows more of it to get closer to the infection. Reason two is that at higher temperatures (102F+) the process parts of the immune system use to kill invading cells works slightly better. This is thought to be one of the reasons mammals get fevers in response to infections and major injuries.
Hot compresses essentially give the body an edge when it comes to fighting a skin infection.
