Shingles

What Is Shingles?

Shingles, also called herpes zoster, is a painful rash that occurs on one side of the face or body and is caused by the varicella zoster virus, which is also responsible for chickenpox.^1,2 People of any age can get chickenpox.² When a person gets chickenpox and recovers, the varicella zoster virus remains dormant in their nerve cells. Later in life, it can reactivate, causing shingles.³

Shingles tends to occur in older adults or in people with a weakened immune system. As a person ages and/or their immune system becomes less effective, the virus can reactivate, migrating from nerve cells to the skin, producing the shingles rash.^2,3

If a person who has never had chickenpox is exposed to someone who has an active shingles infection, they may get chickenpox—not shingles.⁴

Prevalence of Shingles

Shingles is a common condition. About one in every three people experiences a case in their lifetime, and most who do only experience it once. The disease is more common in older people, and the overall risk of shingles increases with age.⁵

Shingles can have serious consequences. For example, between 10% and 18% of patients experience postherpetic neuralgia,³ which is pain that can linger for months or years after the rash clears.^3,6 Complications may require hospitalization in 1% to 4% of patients with shingles. Among patients hospitalized with shingles, 30% have weakened or suppressed immune systems.⁵

Shingles is rarely fatal, resulting in fewer than 100 deaths each year in the U.S. Nearly all these deaths occur among older people or those whose immune systems are weak.⁵

Prior to the availability of a shingles vaccine in 2006,⁷ shingles rates had been increasing in the U.S. For example, in 1998, the country’s incidence rate of shingles was about four cases for every 1,000 adults aged 30 and older. This rate climbed to close to six cases for every 1,000 people by 2016.⁵ Since 2016, the overall incidence in the U.S. has declined, particularly in older adults.^5,8

The Centers for Disease Control and Prevention recommends shingles vaccination for adults age 50 and up and immunocompromised adults age 19 and up.⁹ According to the Centers for Disease Control and Prevention, nearly 35% of adults age 60 and up received the vaccine in 2018. That was an increase from about 7% in 2008.¹⁰ However, shingles vaccination rates among certain groups in the U.S. lag behind others. For example, older adults who are Black or Hispanic are about 50% less likely to be vaccinated for shingles compared with non-Hispanic white adults in the U.S.¹¹

Causes and Risk Factors

What Causes Shingles?

Shingles is caused by the varicella zoster virus. The same virus also causes chickenpox.^2,12 Though the source virus is the same, chickenpox and shingles are two different illnesses, and chickenpox tends to be less severe.¹³

Shingles is caused by the reactivation of varicella zoster virus.² Those who have had and recovered from chickenpox can develop shingles.^2,12 When the chickenpox virus reactivates, the term for the resulting illness is herpes zoster, or shingles.¹²

Shingles typically develops as follows. After a person recovers from chickenpox, the varicella zoster virus lingers in their nerve cells. The virus can then reactivate later in life as the immune system weakens. When the immune system weakens, it loses its ability to keep the virus in check. Having an immune system that is compromised for reasons other than aging can also increase a person’s likelihood of getting shingles.^2,3,12

Shingles Risk Factors

Shingles may occur in individuals who have previously contracted chickenpox, which is true of 99.5% of people born before 1980. It may also occur in those who received a live chickenpox vaccine. But the risk of developing shingles is lower for people who have had the chickenpox vaccine than it is for people who contracted the virus through natural exposure.³

Overall, a person’s shingles risk increases as their immunity declines. This can stem from the natural aging process, so that, overall, shingles risk rises with increasing age.^3,5

But other factors can also weaken a person’s immune system, such as immunosuppressive medications, organ transplants, cancers, and other types of pharmaceuticals—all of which can increase shingles risk.^3,12 Specific factors that may weaken the immune system and contribute to the development of shingles also include chemotherapy treatment and diseases such as HIV/AIDS.^3,12

Research indicates that stress may also be a risk factor for shingles.¹⁴

Shingles Prevention

Vaccination is an effective way to prevent shingles. According to The Centers for Disease Control and Prevention (CDC), the currently recommended shingles vaccine was 97% effective in preventing shingles in healthy adults aged 50 to 69 and 91% effective for adults aged 70 and older.⁹ The CDC recommends that adults aged 50 and older receive two doses of this shingles vaccine between two and six months apart, regardless of whether they’ve previously had chickenpox or shingles.⁹

According to the CDC, shingles vaccination is also recommended for adults with compromised immune systems who are 19 and older. This recommendation applies only to patients with a prior history of chickenpox or of chickenpox vaccination, who have a risk of developing shingles.¹⁵

Vaccination is also available for chickenpox (varicella zoster),¹⁶ the virus that causes shingles.³ Like the shingles vaccine, the chickenpox vaccine is administered in two doses, the timing of which may vary. The CDC recommends that children under the age of 13 receive two doses, with the first dose occurring around 12 to 13 months of life and the second occurring around the ages of 4 to 6 years. For people age 13 or older who have never contracted chickenpox or been vaccinated, the CDC recommends two doses with a minimum of 28 days between them.¹⁶ Specific recommendations have been developed for chickenpox vaccination of individuals with compromised immune systems.¹⁷

Shingles Signs and Symptoms

Shingles may begin as pain that shoots or burns, but it can also start with a tingling or itching feeling. After a few days, the rash emerges. Blisters form as part of the rash and scab in seven to 10 days.^1,12

The rash tends to take a consistent shape, emerging as a stripe that goes around the body’s right or left side.¹ The area in which the rash erupts tends to follow specific nerve connections to the spine. It does not tend to cross the midline of the body.^3,15

Rarely, the rash can be more widespread, resembling chickenpox. This is more typical in people with compromised immune systems.¹² Full healing of the rash and blisters typically takes two to four weeks.³

Pain is a common shingles symptom. Patients sometimes describe it as a shooting or burning sensation, but it also can present as tingling or itching.¹²

Following the onset of these sensations, the shingles rash typically emerges.¹²

In addition to the rash, other accompanying symptoms can include fever, headache, and upset stomach.¹² Some shingles patients also report light sensitivity and malaise prior to the appearance of the rash.³

Shingles Complications

Postherpetic neuralgia is the most common shingles complication.³ It is pain that may linger in the affected area for three months or longer after the shingles rash appears.¹⁸ The more pain a person experiences and the larger the size of the rash, the more likely they are to develop postherpetic neuralgia.³

The risk of postherpetic neuralgia increases with age. For example, between 10% and 13% of people aged 60 and over who have shingles will experience postherpetic neuralgia. By comparison, postherpetic neuralgia occurs in fewer than 5% of cases in people who are under the age of 50 and contract shingles.^3,5,18,19,20

Shingles can also present as ophthalmic shingles—a rash on either or both eyelids. The rash and subsequent blisters can drain and sometimes produce redness or burning in one or both eyes. Cases of ophthalmic shingles can also lead to light sensitivity, blurred vision, redness, pain, or swelling. The disease can even damage the cornea, which is the dome-like structure at the front of the eye that focuses light.^3,21

Other possible complications include:

• Hearing loss²²
• Bacterial infection of the lesions³
• Cranial and peripheral nerve palsy,³ which can lead to partial or total paralysis of certain parts of the face²³
• Effects to the body and nervous system,³ such as meningoencephalitis (the inflammation of certain structures in the brain)²⁴, pneumonitis (irritation or inflammation of lung tissue)²⁵, hepatitis (inflammation in liver tissue)²⁶, and acute retinal necrosis (tissue death in the eyes)²⁷

Shingles Treatment

Shingles treatment options consist of self-care combined with certain over-the-counter and prescribed medications.⁴

For self-care, a healthcare provider may advise you to take a lukewarm oatmeal bath, apply calamine lotion, or use wet compresses to soothe discomfort from the rash. They may also recommend over-the-counter pain relievers.⁴

In certain cases, healthcare providers may prescribe pain medication or may prescribe antiviral medications, which may shorten the duration and severity of shingles. These medications must be initiated close to the onset of the rash.⁴

Global Impact of Shingles

Globally, an estimated three to five people out of every 1,000 will get shingles each year. People who are unvaccinated and live to the age of 85 have a 50% chance of developing the disease in their lifetime.³³

In high-income countries, rates of shingles are similar to those observed in the United States. In low- and middle-income countries, shingles data are limited, making it difficult to gauge the burden of disease.³⁴

Currently, two versions of the shingles vaccine are available around the world. One uses a live version of the virus and the other, called the recombinant vaccine, is based on elements of the viral protein.³⁵ As of 2020, the live vaccine was approved for use in approximately 60 countries around the world. However, the recombinant vaccine showed higher efficacy in clinical trials. It is approved in more than 30 countries, including the U.S., Canada, Japan, Australia, China, and the European Union.³⁴ Certain barriers prevent the widespread global uptake of shingles vaccines. Some countries do not recommend the vaccines, while other countries do not promote them with funding or public education.³⁴