丹毒（英语：Erysipelas）是一种主要由A组β溶血性链球菌引起的急性真皮细菌感染而导致的炎症。

英语：Erysipelas的名称，来自希腊语： ἐρυσίπελας，原意为红皮肤。

在欧洲某些国家，丹毒又称圣火（拉丁语：Ignis sacer，英语：holy fire）、圣安东尼之火（St. Anthony's fire）。中医:朱毛丹

Erysipelas (/ɛrᵻˈsɪpələs/; Greek ἐρυσίπελας, "red skin"; also known as "ignis sacer", "holy fire", and "St. Anthony's fire" in some countries) is an acute infection typically with a skin rash, usually on any of the legs and toes, face, arms, and fingers. It is an infection of the upper dermis and superficial lymphatics, usually caused by beta-hemolytic group A Streptococcus bacteria on scratches or otherwise infected areas. Erysipelas is more superficial than cellulitis, and is typically more raised and demarcated.