Description:
Shown is a close-up of how a herpes simplex lesion on the lower lip looks like on the second day of its life cycle. Also known as cold sores, these lesions should not be confused with canker sores which are generally not contagious. They are caused by the herpes simplex virus type 1 or the HSV-1 which stays in the body all throughout an infected person’s lifetime.

Source: - Picture from CDC/PHIL