Get it to a vet. If it's caused by a fungus, it could end up spreading, almost like gangrene or trench foot. It certainly won't get any better in it's current environment (ie. high humidity and heat will make this worse). if it's an open wound. Is it wild caught? Did it get bit? If you don't get it to a vet I recommend a topical (cortisol or corticosteroid) steroid, and a topical fungicide, keep it dry if you must continue with humidity. Really though, as a responsible keeper, a vet is your best option.
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Corn Snakes
1.0 Blood Red CB
0.2 Normal CB
0.1 Aztec CB
1.0 Anerythristic CB

Morelia Pythons
0.1 Morelia Viridis CB
1.1 Morelia Spilota Cheynei CB

Homo Sapiens Sapiens
0.1 Normal Neonate CB
0.1 Very Bizarre Adult WC