Canker sores, or aphthous ulcers cannot be spread from one person to another. They are a very common mouth sore in women. Canker sores may be mistaken for cold sores or fever blisters, which are caused by the herpes simplex virus and are contagious.
A Answers (3)
American Dental Association answered
Canker sores are not contagious. They can return frequently, but their exact cause is uncertain. Some experts believe that immune system problems, bacteria or viruses may be involved.
Joan Haizlip, MSN, Cardiology, answeredCanker sores (aphthous ulcers) are not contagious, meaning they cannot be spread from one person to another. Canker sores are different from cold sores or fever blisters which are caused by the herpes simplex virus. Cold sores and fever blisters are contagious.