In response to the enquiry: “Do blisters become gangrene?”
“A blister is an elevation of the epidermis containing watery liquid” (Merriam-Webster’s Medical Dictionary). By definition, a blister is not an open sore.
Clostridia bacteria that causes gangrene cannot penetrate unbroken skin. Clostridia bacteria can only enter through an already open wound. A blister is not an open wound.