Why does herpes cause repeated outbreaks?

After a person is first infected, the herpes virus travels to nerve cells near the spine and stays there. When there is a trigger, the virus can become active again. Triggers can include illness, stress, and hormonal changes.

When the virus is active again, it travels along the nerves, back to where it first entered the body, and causes a new outbreak of sores and blisters (one of the symptoms of herpes). This is called a recurrence.

The virus can be passed to others during a recurrence. It’s also important to know that you can pass HSV to someone else even when you do not have sores. The virus can be present on skin that looks normal, including right before and after an outbreak.

See Genital Herpes to learn more.

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This information is designed as an educational aid for the public. It offers current information and opinions related to women's health. It is not intended as a statement of the standard of care. It does not explain all of the proper treatments or methods of care. It is not a substitute for the advice of a physician. Read ACOG’s complete disclaimer.