What are the chances of a skin infection(pus in skin,inflamed,painful) developing into necrotizing fasciitis?

Rate Dependent: NecFasc happens fast. By the time your in the hospital, your organs are failing, let alone the actual limb or skin region. It's rare. Very common is cellulitis, carbuncles, erysipelas, all degrees of the same thing, an infection starting at the skin. Then there are abscesses, when the body forms a wall containing pus. They are by far more common, People with Necfasc have hard time getting into ER.