Medical Edge Newspaper Column

Shingles Isn't Contagious, But Keep Chicken Pox in Mind

December 3, 2007
Dear Mayo Clinic:
Is shingles contagious?

Answer:
Yes and no. You can't catch shingles from another person. But shingles is caused by the same virus that causes chicken pox. The virus, called varicella zoster, can be spread by person-to-person contact. So, if you've never had chicken pox, you should stay away from people who have shingles because you could contract chicken pox from them.

Shingles results from the varicella zoster virus that's left behind in your body after you've had chicken pox. After you recover from the acute attack of chicken pox, the virus remains in nerve cells next to your spinal cord. Then, many years later, the virus can reactivate and result in shingles.

Typically, shingles appears as a painful band-like rash of tiny blisters somewhere on the trunk of your body, though it may also affect your face, neck and scalp, or even a limb. A hallmark of typical shingles is that the rash appears only on one side of your body – either the left or right side. For example, it may start in the middle of your back and wrap around your chest to your breastbone. This happens because the virus follows the path of the infected nerve, which serves only one side of the body.

If you're an adult who hasn't had chicken pox, it's important to avoid close contact with people with shingles because an adult case of chicken pox is usually more intense than chicken pox in children. Most kids recover from chicken pox in about a week, and the illness is generally mild. In adults, the rash is usually more severe, and serious complications can occur, such as pneumonia or brain inflammation (encephalitis).

Shingles is fairly common in people who have had chicken pox. About 20 percent of people (or one in every five) who've had chicken pox will develop shingles at least once in their lifetime.

Your risk of developing shingles increases if your body's immune system has been compromised by a condition like rheumatoid arthritis, or by other factors, including chemotherapy, radiation therapy or medications like steroids. Age can also reduce your immune system's effectiveness, which may explain why shingles is more likely to occur when you're older.

The best way to reduce your risk of shingles is to get the shingles vaccine. The Centers for Disease Control and Prevention (CDC) recommends that everyone over the age of 60 consider vaccination. Anyone can request the vaccine but it is not inexpensive and your insurance may or may not cover the cost. In addition, because the shingles vaccine is a live vaccine, it is not recommended for people who have weakened immune systems due to medication, illness or medical treatment; women who are pregnant; or anyone who has active tuberculosis.

The shingles vaccine can cut your risk of developing shingles by as much as 50 percent. It can also decrease your risk of "postherpetic neuralgia," a painful complication of shingles that results from virus-induced damage to nerve cells and can last for weeks to months.

A shingles vaccination doesn't guarantee that you'll never get shingles. But if you get shingles, the vaccine will likely reduce the length and severity of the illness. For more information about the shingles vaccine, talk to your doctor.

— Priya Sampathkumar, M.D., Infectious Diseases, Mayo Clinic, Rochester, Minn.