Shingles is a viral infection that causes a painful rash. Shingles can occur anywhere on your body. It typically looks like a single stripe of blisters that wraps around the left side or the right side of your torso.
Shingles is caused by the varicella-zoster virus — the same virus that causes chickenpox. After you've had chickenpox, the virus stays in your body for the rest of your life. Years later, the virus may reactivate as shingles.
Shingles isn't life-threatening. But it can be very painful. Vaccines can help lower the risk of shingles. Early treatment may shorten a shingles infection and lessen the chance of complications. The most common complication is postherpetic neuralgia. This is a painful condition that causes shingles pain for a long time after your blisters have cleared.
Shingles symptoms usually affect only a small section on one side of your body. These symptoms may include:
- Pain, burning or tingling
- Sensitivity to touch
- A red rash that begins a few days after the pain
- Fluid-filled blisters that break open and crust over
Some people also experience:
- Sensitivity to light
Pain is usually the first symptom of shingles. For some people, the pain can be intense. Depending on the location of the pain, it can sometimes be mistaken for problems with the heart, lungs or kidneys. Some people experience shingles pain without ever developing the rash.
Most commonly, the shingles rash develops as a stripe of blisters that wraps around either the left or right side of the torso. Sometimes the shingles rash occurs around one eye or on one side of the neck or face.
When to see a doctor
Contact your health care provider as soon as possible if you suspect shingles, especially in the following situations:
- The pain and rash occur near an eye. If left untreated, this infection may lead to permanent eye damage.
- You're 50 or older. Age increases your risk of complications.
- You or someone in your family has a weakened immune system. This may be due to cancer, medications or chronic illness.
- The rash is widespread and painful.
Shingles is caused by the varicella-zoster virus — the same virus that causes chickenpox. Anyone who's had chickenpox may develop shingles. After you recover from chickenpox, the virus enters your nervous system and stays inactive for years.
Sometimes the virus reactivates and travels along nerve pathways to your skin — producing shingles. But not everyone who's had chickenpox will develop shingles.
The reason for shingles is unclear. It may be due to lowered immunity to infections as people get older. Shingles is more common in older adults and in people who have weakened immune systems.
Varicella-zoster is part of a group of viruses called herpes viruses. This is the same group that includes the viruses that cause cold sores and genital herpes. As a result, shingles is also known as herpes zoster. But the virus that causes chickenpox and shingles isn't the same virus that causes cold sores or genital herpes, which is a sexually transmitted infection.
Are you contagious?
A person with shingles can pass the varicella-zoster virus to anyone who isn't immune to chickenpox. This usually occurs through direct contact with the open sores of the shingles rash. Once infected, though, the person will develop chickenpox rather than shingles.
Chickenpox can be dangerous for some people. Until your shingles blisters scab over, you are contagious. Avoid physical contact with anyone who hasn't yet had chickenpox or the chickenpox vaccine. That includes people with weakened immune systems, pregnant women and newborns.
Anyone who has ever had chickenpox can develop shingles. Most adults in the United States had chickenpox when they were children. That was before the availability of the routine childhood vaccination that now protects against chickenpox.
Factors that may increase your risk of developing shingles include:
- Age. The risk of developing shingles increases with age. Shingles typically occurs in people older than 50. And people over the age of 60 are more likely to experience more-severe complications.
- Some diseases. Diseases that weaken your immune system, such as HIV/AIDS and cancer, can increase your risk of shingles.
- Cancer treatments. Radiation or chemotherapy can lower your resistance to diseases and may trigger shingles.
- Some medications. Drugs that prevent rejection of transplanted organs can increase your risk of shingles. Long-term use of steroids, such as prednisone, may also increase your risk of developing shingles.
Complications from shingles can include:
- Postherpetic neuralgia. For some people, shingles pain continues long after the blisters have cleared. This condition is known as postherpetic neuralgia. It occurs when damaged nerve fibers send confused and exaggerated messages of pain from your skin to your brain.
- Vision loss. Shingles in or around an eye (ophthalmic shingles) can cause painful eye infections that may result in vision loss.
- Neurological problems. Shingles may cause inflammation of the brain (encephalitis), facial paralysis, or problems with hearing or balance.
- Skin infections. If shingles blisters aren't properly treated, bacterial skin infections may develop.
A shingles vaccine may help prevent shingles. People who are eligible should get the Shingrix vaccine, which has been available in the United States since its approval by the Food and Drug Administration in 2017. The Zostavax vaccine is no longer available in the U.S., but other countries may still use it.
Shingrix is approved and recommended for people age 50 and older, whether they've had shingles or not. People who've had the Zostavax vaccine in the past or don't know whether they've had chickenpox may also receive the Shingrix vaccine.
Shingrix is also recommended for people who are 19 years of age and older who have weakened immune systems due to disease or medication.
Shingrix is a nonliving vaccine made of a virus component. It's given in two doses, with 2 to 6 months between doses. The most common side effects of the shingles vaccine are redness, pain and swelling at the injection site. Some people also experience fatigue, headache and other side effects.
The shingles vaccine doesn't guarantee that you won't get shingles. But this vaccine will likely reduce the course and severity of the disease. And it will likely lower your risk of postherpetic neuralgia. Studies suggest that Shingrix offers protection against shingles for more than five years.
Talk to your health care provider about your vaccination options if you:
- Have had an allergic reaction to any component of the shingles vaccine
- Have a weakened immune system due to a condition or medication
- Have had a stem cell transplant
- Are pregnant or trying to become pregnant
The shingles vaccine is used only as a way to prevent shingles. It's not intended to treat people who currently have the disease.