Around a million diagnosed cases of shingles (herpes zoster) occur annually in the United States. 

To help you understand more, we've answered some of the most common questions about the shingles virus here.

What is shingles and what causes it?

The varicella-zoster virus that causes chickenpox is the same virus that causes shingles. When you've had chickenpox as a child or teenager, the physical signs disappear as your body fights off the virus. However, the virus always remains in your body and can reactivate as you age.

For some, the virus stays in the body quietly in a portion of your spinal nerve root called the dorsal root ganglion. For others, the virus can become reactivated and develop into shingles. 

What does shingles feel and look like?

A viral infection, shingles cause an outbreak of a painful rash that may appear as a band-like rash of fluid-filled blisters along one area of your body. For most patients, the rash is usually on one side of the body, where the nerve is located. Shingles won't typically spread over your whole body but is localized to that particular nerve distribution.

Early symptoms may include:

• Stabbing or shooting pain before the rash appears
• Painful raised rash with fluid-filled blisters
• Tingling or burning along the affected area
• Redness on the skin in the affected area

Additional symptoms that may or may not accompany the rash:

• Headache
• Fever
• Fatigue
• Upset stomach

Within about 10 days, the blisters may begin to dry out and crust over, clearing up approximately two to three weeks later.

Who is at risk?

If you've had chickenpox, you are more susceptible as you age. About 50% of people who live to age 85 will have had some shingles event in their lives. Shingles can develop for a variety of reasons, especially for those:

• Over the age of 50, with increasing risk with each decade
• With a weakened immune system, such as those with cancer, HIV, transplant recipients, or patients receiving chemotherapy
• With an autoimmune disease
• Who may have a weakened immune system due to trauma or illness

What complications can happen with shingles?

The most common complication after the shingles rash disappears is postherpetic neuralgia. This condition causes nerve pain, numbness, or tingling in the same area as the rash and can last for 90 or more days after the rash appears.

Other complications, some severe, include:

• Bacterial infection of the rash
• Herpes zoster ophthalmicus causes eye problems when shingles is severe on the face, near the eyes, impacting sight. When very severe, blindness can occur 
• Ramsay Hunt syndrome (herpes zoster oticus) causes problems within the ear's auditory canal or external parts. It is accompanied by ear pain, internal or external blisters, and one-sided facial paralysis

Is shingles contagious?

The virus can spread through direct skin-to-skin contact from the fluid in the blisters. If your rash is in the blister phase, it’s best to avoid close contact with anyone, regardless of immunization or immunocompromised status, and keep the rash covered. Consider yourself contagious until the rash is dried and crusted over. "Shingles can also rarely be spread via airborne transmission from individuals with localized lesions," says Stephen Mohring, MD, Nebraska Medicine internal medicine physician. "So take care when you are around others who have shingles or chickenpox."

Once you've had shingles, can it come back?

Reoccurrence is relatively uncommon. Only a small percentage (about 1% to 6%) of patients may have a second episode, more commonly in women. "Three or more shingles episodes in the same person is considered extremely rare," says Dr. Mohring. "In this case, it would prompt us to investigate other potential diseases that may be going on. Those with higher risk factors, especially weakened immune systems or autoimmune disease, are the most at risk for reoccurrence."

When should I see a doctor? 

If you think you may have shingles, see your doctor as soon as possible. "Treatment is most effective when given within 72 hours of the appearance of rash and blisters," advises Dr. Mohring. "Any rash accompanied by pain, including fever or headache, should prompt you to have a conversation with your doctor, especially if it's a fluid-filled blister."

How is shingles treated?

While there is no cure for shingles, see a doctor quickly to discuss your treatment options. Typically, oral antivirals are used, which can be prescribed by your primary care or an urgent care doctor. An anti-inflammatory drug (steroids) may be prescribed if the rash affects your eyes or other parts of the face. In rare incidences, hospitalizations can occur in very severe, complicated cases. 

Should I get the shingles vaccine?

"Because the vaccine has been shown to reduce the risk of developing herpes zoster and shingles complications, getting the vaccine is highly recommended," says Dr. Mohring. "I strongly recommend it for all patients 50 years or older and those who are immunocompromised. It's safe and effective and reduces severity if you have a breakthrough episode." 

The Shingrix vaccine is a two-dose series given two to six months apart. It's been shown to be over 90% effective in preventing shingles and postherpetic neuralgia and remains over 85% effective for at least four years afterward. You will not get shingles from this vaccine, and it is generally safe for those with weakened immune systems.