What is shingles?
Shingles (also known as herpes zoster virus) is a neurological disorder caused by the reactivation of a viral infection in the skin's nerves. Shingles causes pain, burning, or a tingling sensation, along with itching and blisters. Most often the painful rash develops as a band or stripe on one side of the body or face and the blisters typically scab over within a week to 10 days. Sometimes shingles can affect the eyes and cause vision loss.
Shingles is caused by the varicella zoster virus (VZV)—the same virus that causes chickenpox. When the itchy red spots of childhood chickenpox disappear, the virus remains hidden in a dormant state in nerve cells, ready to strike again in later life, most often in adulthood. When the virus reactivates (the cause is unknown), it is called shingles or herpes zoster virus. Fortunately, most adults who have had chickenpox never get shingles.
You cannot develop shingles unless you have had an earlier exposure to chickenpox. And you cannot "catch" shingles from someone else. But if you have active shingles, contact with the fluid from your blisters can pass the virus to someone who has never had chickenpox or the chickenpox vaccine. If they get infected, they will develop chickenpox, not shingles.
When you are originally exposed to VZV (chickenpox), some of the virus particles settle into nerve cells (neurons) of sensory ganglia (a group of nerve cells that connect the sensory periphery and central nervous system), where they remain for many years in an inactive, hidden (latent) form. The neurons in the sensory ganglia have nerve fibers that supply the skin and relay information to the brain about what the body is sensing, including heat, cold, touch, pain.
When VZV reactivates, it spreads down the long nerve fibers (axons) that extend from sensory cell bodies to your skin. As the virus multiplies, the rash erupts. With shingles, the nervous system is more deeply involved than it was during chickenpox, and the symptoms are often more complex and severe.
The most common symptoms of shingles include:
- Burning or tingling pain, or itching—This often appears as a first symptom of shingles and generally occurs in a band-like distribution on one side of the body (i.e., around the waist, chest, stomach, or back). Shingles pain can be mild or intense. Some people have mostly itching while others might feel severe pain from the gentlest touch, such as the weight of bed linens or clothing.
A rash of fluid-filled blisters (vesicles)—This usually appears after several days or up to two weeks after the first symptoms are felt. This is similar to chickenpox but the blisters occur in a cluster rather than scattered over the body. Some rashes merge and produce an area that looks like a burn. Other people may have a few small, scattered lesions. The clusters most often appear in a band called a dermatome, which contains nerves that branch out from the virus-affected nerve root exiting the spine. The second most common location is on one side of the face around the eye and on the forehead. However, shingles can involve any part of the body, including internal organs. Recent studies have shown that subtle cases of shingles with only a few blisters, or none, are more common than previously thought. These cases may go unrecognized.
A few people may have general symptoms of a viral infection, like fatigue, fever, and headache. Some people who have had shingles develop postherpetic neuralgia—a burning pain that can last for weeks or more after the blisters are gone.
Who is more likely to get shingles?
Anyone who previously had chickenpox is at risk for shingles. About 25 percent of all adults, mostly healthy otherwise, will get shingles during their lifetime, usually after age 50. Its incidence increases with age so that shingles is 10 times more likely to occur in adults over the age of 60 than in children under 10. People with compromised immune systems, either from aging or use of immune-suppressant drugs to treat another condition, have a higher risk of developing shingles. Some people can also have re-eruptions and some, particularly those with significantly impaired immunity from drugs and diseases, may have shingles that spread over the body.
Most people who get shingles have it only once, but it is possible for the outbreak to appear again.
Some infections can be transmitted across the mother's bloodstream to the fetus or can be acquired by the baby during the birth process. Children whose female parent had chickenpox late in pregnancy—five to 21 days before giving birth—or who had chickenpox in infancy have an increased risk of pediatric shingles. Sometimes these children are born with chickenpox or develop a typical case within a few days. Most experts agree that shingles in a pregnant person is less likely to cause harm to the unborn child.
How is shingles diagnosed and treated?
Shingles is usually diagnosed based on its distinctive signs and symptoms:
- Pain on one side of the body
Your doctor will do a complete physical exam, ask about your medical history—specifically about whether you have ever had chickenpox, and also may take a skin scraping for testing.
Currently, there is no cure for shingles, but attacks can be made less severe and shorter by using prescription antiviral drugs such as acyclovir, valacyclovir, or famcyclovir as soon as possible after symptoms begin. Early treatment can reduce or prevent severe pain and help blisters dry faster. Antiviral drugs can reduce the risk of being left with postherpetic neuralgia by about half.
Doctors recommend starting antiviral drugs at the first sign of the shingles rash, or if the symptoms indicate that a rash is about to erupt. Other treatments to consider are anti-inflammatory corticosteroids such as prednisone, which is routinely used when the eyes or other facial nerves are affected.
Most people with shingles can be treated at home.
People with shingles should also try to:
- Relax and reduce stress (stress can make pain worse and lead to depression)
- Eat regular, well-balanced meals
- Perform gentle exercises, such as walking or stretching to keep active and stop thinking about the pain (but check with your physician)
Placing a cool, damp washcloth on the blisters when not wearing a topical cream or patch can help blisters dry faster and relieve pain. Keeping the area clean can also help avoid a secondary bacterial infection.
The Food and Drug Administration (FDA) has approved two vaccines—Zostavax and Shingrix—for people 50 and older who have had chickenpox. Talk with your doctor if you have questions about shingles vaccination.
The shingles vaccine is a preventive therapy and not a treatment for those who already have shingles or postherpetic neuralgia.
The varicella or chickenpox vaccine—now recommended in the U.S. for all children between 18 months and adolescence—can protect people from getting chickenpox. People who have been vaccinated against chickenpox are probably less likely to get shingles because the weak, “attenuated” strain of virus used in the chickenpox vaccine is less likely to survive in the body over decades.
Sometimes, particularly in older people, shingles pain persists long after the rash has healed. This postherpetic neuralgia, defined as pain lasting three months after onset of the rash, can be mild or severe—the most severe cases can lead to insomnia, weight loss, depression, and disability. There may be other sensations, such as tingling, coldness, or loss of feeling. Postherpetic neuralgia is not directly life-threatening and may get better over time. Treatment may include:
- Tricyclic antidepressants
- Topical local anesthetics such as lidocaine or capsaicin
The itch that sometimes occurs during or after shingles can be quite severe and painful. Clinical experience suggests that postherpetic itch is harder to treat than postherpetic neuralgia. Topical local anesthetics (which temporarily numb the skin) provide substantial relief to some individuals. Since postherpetic itch typically develops in skin that has severe sensory loss, it is particularly important to avoid scratching. Scratching numb skin too long or too hard can cause injury.
Other complications of shingles
Complications of shingles are more frequent in people with lesions in or around the eyes, forehead, and nose (ophthalmic shingles), or around the ear and on the face (herpes zoster oticus or Ramsay-Hunt syndrome). People with shingles in or near the eye should see an ophthalmologist immediately, as painful eye infections can occur and, in some cases, cause temporary or permanent vision loss. Symptoms can include redness and swelling involving:
- Just the white of the eye (sclera)
- The clear front of the eye (cornea)
- Internal parts of the eye
If the cornea is involved, treatment is needed to avert permanent scarring and prevent lasting vision loss. The disease can cause damage to or death of the nerve cells that react to light (acute retinal necrosis).
Shingles infections inside or near the ear can cause hearing or balance problems as well as weakness of the muscles on the affected side of the face. These problems can be long-lasting or permanent.
In rare cases, shingles can spread into the brain or spinal cord and cause serious complications such as stroke or meningitis (an infection of the membranes outside the brain and spinal cord).
VZV also may involve blood vessels or provoke an immune reaction irritating the surface of blood vessels (vasculopathy). People with shingles have slightly increased risk of stroke, which is greatest in the first few weeks after blisters erupt but can last for several months. The increased risk of stroke is highest in people with eye zoster.
People with shingles need to seek immediate medical evaluation if they notice neurological symptoms outside the region of the primary shingles attack. People who are immunosuppressed, whether from diseases such as HIV and leukemia or medications, have an increased risk of serious complications from shingles. They may develop shingles that spreads to involve more parts of the body, or shingles rashes that persist for long periods or return frequently. Many such individuals are helped by taking antiviral medications on a continuous basis.
What are the latest updates on shingles?
The National Institute of Neurological Disorders and Stroke (NINDS) is a component of the National Institutes of Health (NIH), the leading supporter of biomedical research in the world.
Research on shingles has two main goals.
- The first is to develop drugs to fight the disease and to prevent or treat its complications.
- The second is to understand the disease well enough to prevent it, especially in people at high risk.
To achieve these goals, scientists need to learn much more about VZV and its effects, including how it becomes latent in nerve cells (neurons), what causes it to become active again, and how such reactivation can lead to postherpetic neuralgia or other complications.
For example, NINDS supports research on the relationship between the viral proteins and virus defense mechanisms in neurons to understand why the varicella-zoster virus establishes latency uniquely in neurons and not in other cell types. Other studies focus on how VZV travels along sensory nerve fibers, or axons, and its role in latency and viral reactivation. Scientists also hope to identify molecular mechanisms that regulate the expression of latent viral genes, which may lead to targeted therapy to prevent reactivation.
Research on postherpetic neuralgia includes studies to better understand cellular changes that lead to persistent pain. These changes may represent future targets in the form of improved vaccines, new medicines, or even gene therapy.
In addition to NINDS, several other NIH institutes support research relevant to understanding, treating, or preventing shingles and its complications, including the National Institute of Allergy and Infectious Diseases (NIAID) and the National Institute on Aging (NIA).
To find more information about shingles research, visit:
- NIH RePORTER is a searchable database of current and previously funded research supported by NIH and some other federal agencies. RePORTER also includes links to research results such as patents and publications citing support from these projects.
- PubMed allows users to search millions of journal article abstracts in biomedical research fields. The full text of many articles describing research funded by NIH and other sources is also available for free through PubMedCentral (PMC).
How can I or my loved one help improve care for people with shingles?
Consider participating in a clinical trial so clinicians and scientists can learn more about shingles. Clinical research uses human volunteers to help researchers learn more about a disorder and perhaps find better ways to safely detect, treat, or prevent disease.
All types of volunteers are needed—those who are healthy or may have an illness or disease—of all different ages, sexes, races, and ethnicities to ensure that study results apply to as many people as possible, and that treatments will be safe and effective for everyone who will use them.
For information about participating in clinical research visit NIH Clinical Research Trials and You. Learn about clinical trials currently looking for people with shingles at Clinicaltrials.gov, a database of current and past clinical studies.
Where can I find more information about shingles?
Information may be available from the following resources:
American Chronic Pain Association (ACPA)
Phone: 916-632-0922 or 800-533-3231
National Institute on Aging (NIA)
Phone: 301-496-1752 or 800-222-2225; 800-222-4225
National Shingles Foundation