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What is herpes?

Herpes infections can cause sores on the mouth or genitals, depending on the strain of herpes virus. People who have it should take steps to avoid passing it on.

Herpes is a virus that produces blister-like sores. They usually appear on the mouth, nose, buttocks and genitals.

Once contracted, the herpes virus doesn't leave the body. The flare-ups that cause the sores occur at differing intervals. The intervals vary from weeks to years.

In between flare-ups, the virus lies dormant in the nerve cells. Stress, fever or menstruation may trigger flare-ups. In many cases, the flare-ups aren't linked to any cause.

Herpes simplex virus type 1 (HSV-1) usually appears on the face during infancy or childhood. The infection is often called a fever blister or cold sore. This virus usually spreads through saliva in nonsexual, close contact with a family member or friend. It can also be transmitted on eating utensils or towels.

Herpes simplex virus type 2 (HSV-2) is almost always a sexually transmitted infection. Most people with HSV-2 are not aware of their infection, according to the Centers for Disease Control and Prevention. However, sores may appear on the buttocks, genitals or cervix.

In addition to the sores, symptoms of this virus may include fever, muscle aches and burning during urination.

Both viruses are contagious before and during an outbreak of sores. An outbreak may be preceded by tingling, burning, itching or tenderness in the area of a previous sore. During this time the affected area should be kept away from other people. Neither clothing nor towels should be shared.

Herpes is a serious disease. It can cause eye infections or spread to a baby as it's being born. Anyone with active sores should not be in contact with an infant.

For people with weakened immune systems, such as those with cancer or recent transplant operations, herpes can be life-threatening.

Additional source: Office on Women's Health

Reviewed 10/26/2021

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