Acne is a disease of the hair follicles of the face, chest, and back that affects almost all teenagers during puberty -- the only exception being members of a few primitive Neolithic tribes living in isolation. It is not caused by bacteria, although bacteria play a role in its development. It is not unusual for some women to develop acne in their mid- to late-20s.
Acne vulgaris is typical teenage acne which is characterized by three types of lesions:
the comedo or blackhead;
the inflammatory papule;
andthe pustule or pimple.
