My advice would be to treat any wound which does not heal up properly and quickly as an infection, (meaning something like a spiderbite/minor scrape or burn should dry up in about a day) using honey or iodine povidone or hydrogen peroxide or alcohol (preference in that order, honey being best). If the treatment isn't showing results after a day and/or it seems to be getting worse, see a doctor, because it is beyond your ability (or whoever is trying to help you) to treat it!
Burns and bites are the most likely wounds to get infected, because they are hard to clean. Untreated human bites are potentially lethal because our mouth bacteria is almost like a slow-acting venom, seriously!
If there is swelling which occurs pretty quickly, a funny smell, colored pus, multiple sites, a vein-like pattern coming out from the point of the wound, fever, or anything unusual, get to a doctor within a few hours if you can, because that means you might die or lose your limbs or become disfigured.
Do people agree with this?