What is Shingles ? ('Snake' rashes, in Chinese)

Shingles (herpes zoster) is a viral infection of the nerve roots. It causes pain and often causes a rash on one side of the body, the left or right. The rash appears in a band, a strip, or a small area. Shingles is most common in older adults and people who have weak immune systems because of stress, injury, certain medicines, or other reasons. Most people who get shingles will get better and will not get it again

What causes shingles ?

Shingles occurs when the virus that causes chickenpox starts up again in your body. After you get better from chickenpox, the virus ”sleeps” (is dormant) in your nerve roots. In some people, it stays dormant forever. In others, the virus “wakes up” when disease, stress, or aging weakens the immune system. It is not clear why this happens. But after the virus becomes active again, it can only cause shingles, not chickenpox. You can't catch shingles from someone else who has shingles.

What are the symptoms ?

Shingles symptoms happen in stages. At first you may have a headache or be sensitive to light. You may also feel like you have the flu but not have a fever.

Later, you may feel itching, tingling, or pain in a certain area. That’s where a band, strip, or small area of rash may occur a few days later. The rash turns into clusters of blisters. The blisters fill with fluid and then crust over. It takes 2 to 4 weeks for the blisters to heal, and they may leave scars. Some people only get a mild rash, and some do not get a rash at all.

What are the causes ?

Shingles is a reactivation of the varicella-zoster virus, a type of herpes virus that causes chickenpox. After you have had chickenpox, the virus lies inactive in your nerve roots and remains inactive until, in some people, it flares up again. When the virus becomes active again, you get shingles instead of chickenpox.

Anyone who has had even a mild case of chickenpox can get shingles. People who have a weak immune system are vulnerable to reactivation of the virus that causes shingles. Many factors can weaken your immune system, including aging, injury, and illness. Some medicines slow down the immune system. For example, medicines that destroy cancer cells (chemotherapy) can interfere with the immune system.

Transmission :
Exposure to shingles will not cause you to get shingles. But if you have not had chickenpox and you are exposed to shingles, you can get chickenpox. Someone with shingles can potentially expose you to chickenpox if you come into contact with the fluid in the shingles rash blisters.

One study reports that the virus that causes shingles may be released into the air from shingles sores. Covering the shingles sores with a type of dressing that absorbs fluids and protects the sore (hydrocolloid dressing, such as DuoDerm) appears to effectively contain the virus.

Symptoms :
When the virus that causes chickenpox reactivates, it causes shingles. Early symptoms of shingles include headache, sensitivity to light, and flu-like symptoms without a fever. You may then feel itching, tingling, or pain where a band, strip, or small area of rash may appear several days or weeks later. A rash can appear anywhere on the body but will be on only one side of the body, the left or right. The rash will first form blisters, then scab over, and finally clear up over a few weeks. This band of pain and rash is the clearest sign of shingles.

The rash caused by shingles is more painful than itchy. The nerve roots that supply sensation to your skin run in pathways on each side of your body. When the virus becomes reactivated, it travels up the nerve roots to the area of skin supplied by those specific nerve roots. This is why the rash can wrap around either the left or right side of your body, usually from the middle of your back toward your chest. It can also appear on your face around one eye. It is possible to have more than one area of rash on your body.

Shingles develops in stages :

a) Prodromal stage (before the rash appears)

a.1) Pain, burning, tickling, tingling, and/or numbness occurs in the area around the affected nerves several days or weeks before a rash appears. The discomfort usually occurs on the chest or back, but it may occur on the abdomen, head, face, neck, or one arm or leg.

a.2) Flu-like symptoms (usually without a fever), such as chills, stomachache, or diarrhea, may develop just before or along with the start of the rash.

a.3) Swelling and tenderness of the lymph nodes may occur.

b) Active stage (rash and blisters appear)

b.1) A band, strip, or small area of rash appears. It can appear anywhere on the body but will be on only one side of the body, the left or right. Blisters will form. Fluid inside the blister is clear at first but may become cloudy after 3 to 4 days. A few people won't get a rash, or the rash will be mild.

b.2) A rash may occur on the forehead, cheek, nose, and around one eye (herpes zoster ophthalmicus), which may threaten your sight unless you get prompt treatment.

b.3) Pain, described as “piercing needles in the skin,” may accompany the skin rash.

b.4) Blisters may break open, ooze, and crust over in about 5 days. The rash heals in about 2 to 4 weeks, although some scars may remain.

c) Postherpetic neuralgia (chronic pain stage)
Postherpetic neuralgia is the most common complication of shingles. It lasts for at least 30 days and may continue for months to years. Symptoms are:

c.1) Aching, burning, stabbing pain in the area of the earlier shingles rash.

c.2) Persistent pain that may linger for years.

c.3) Extreme sensitivity to touch.

The pain associated with postherpetic neuralgia most commonly affects the forehead or chest, and it may make it difficult for the person to eat, sleep, and perform daily activities. It may also lead to depression.
Shingles may be confused with other conditions that cause similar symptoms of rash or pain, such as herpes simplex infection or appendicitis.

What are the reactions ?

Shingles is caused by the same virus that causes chickenpox. After an attack of chickenpox, the virus remains in the tissues in your nerves. As you get older, or if you have an illness or stress that weakens your immune system, the virus may reappear in the form of shingles.

You may first experience a headache, flu-like symptoms (usually without a fever), and sensitivity to light, followed by itching, tingling, or pain in the area where a rash may develop. The pain usually occurs several days or weeks before a rash appears on the left or right side of your body. The rash will be in a band, a strip, or a small area. Within 3 to 5 days, the rash turns into fluid-filled blisters that ooze and crust over. The rash heals in about 2 to 4 weeks, although you may have long-lasting scars.4 A few people won't get a rash, or the rash will be mild.

Most people who get shingles will not get the disease again.

Complications of shingles include :

1) Postherpetic neuralgia, which is pain that does not go away within 1 month. It may last for months or even years after shingles heals. Postherpetic neuralgia affects up to 10% to 15% of those who experience shingles.6 It is more common in people age 50 and older, and in people who have a weakened immune system due to another disease, such as diabetes or HIV infection. People who have severe pain and rash during shingles have an increased risk for postherpetic neuralgia.

2)Disseminated zoster, which is a blistery rash that spreads over a large portion of the body and can affect the heart, lungs, liver, pancreas, joints, and intestinal tract. Infection may spread to nerves that control movement, which may cause temporary weakness.

3) Cranial nerve complications. If shingles affects the nerves originating in the brain (cranial nerves), complications may include :

3.1) Inflammation, pain, and loss of feeling in one or both eyes. The infection may threaten your vision. A rash may appear on the side and tip of the nose (Hutchinson's sign).

3.2) Intense ear pain, a rash around the ear, mouth, face, neck, and scalp, and loss of movement in facial nerves (Ramsay Hunt syndrome). Other symptoms may include hearing loss, dizziness, and ringing in the ears. Loss of taste and dry mouth and eyes may also occur.

3.3) Inflammation, and possibly blockage, of blood vessels, which may lead to stroke.

4) Scarring and skin discoloration.

5) Bacterial infection of the blisters.

6) Muscle weakness in the area of the infected skin before, during, or after the episode of shingles.

Risks for developing shingles include:

* Having had chickenpox. You must have had chickenpox to get shingles.

* Being older than 50.

* Having a weakened immune system due to another disease, such as diabetes or HIV infection.

* Experiencing stress or trauma.

* Developing chickenpox prior to age 1.

* Having cancer or receiving treatment for cancer.

If a pregnant woman gets chickenpox, her baby has a high risk of developing shingles within his or her first 2 years of life.

Postherpetic neuralgia is a common complication of shingles that lasts for at least 30 days and may continue for months to years. If more than one of the following risk factors is present, your risk increases for postherpetic neuralgia :

a) Developing shingles after age 50

b) Having severe pain and rash during shingles

c) Being female

Call your health professional immediately if :

a) Any sign of shingles develops (such as pain or changes in vision) on or in the area of your forehead, nose, eye, or eyelid.

b) Any symptoms of shingles develop (such as headache, stiff neck, dizziness, weakness, hearing loss, or changes in your thinking and reasoning abilities) that affect your central nervous system.

c) Skin sores spread to parts of your body beyond the original area of the rash.

d) You think you have a bacterial skin infection in the same area as the shingles rash, or your rash has not healed in 2 to 4 weeks.

e) You develop pain in your face or are unable to move muscles in your face.

Call your health professional today if :

You suspect you might have shingles. There are medications that can limit your pain and rash. The earlier you start treatment for shingles, the better the results.