Shingles - Herpes Zoster

We have selected the following expert medical opinion based on its clarity, reliability and accuracy. Credits: Sourced from the website Patient UK, authored by Dr Mary Harding (see below). Please refer to your own medical practitioner for a final perspective, assessment or evaluation.

Overview 

What is shingles?

Shingles is a painful, blistery rash in one specific area of your body. Most of us get chickenpox in our lives, usually when we are children. Shingles is a reactivation of that chickenpox virus but only in one nerve root. So instead of getting spots all over the place, the way you do when you have chickenpox, you get them just in one area of your body.

Usually (other than on your head) it will just be on one side of your body, although it may go right round from front to back, following the skin the nerve affects.

The affected skin hurts, and it may start to hurt before the rash appears, and may keep hurting for some time after the rash has gone. You may feel generally off-colour and not yourself.

How common is it?

Shingles is an infection of a nerve and the area of skin supplied by the nerve. It is caused by a virus called the varicella-zoster virus. It is the same virus that causes chickenpox. Anyone who has had chickenpox in the past may develop shingles. Shingles is sometimes called herpes zoster. (Note: this is very different to genital herpes which is caused by a different virus called herpes simplex).

About 1 in 4 people have shingles at some time in their lives. It can occur at any age, but it is most common in people over the age of 50 years. After the age of 50, it becomes increasingly more common as you get older. It is uncommon to have shingles more than once, but some people do have it more than once.

Symptoms

What are the symptoms of shingles?

The virus usually affects one nerve only, on one side of the body. Symptoms occur in the area of skin that the nerve supplies. The usual symptoms are pain and a rash. Occasionally, two or three nerves next to each other are affected.

The most commonly involved nerves are those supplying the skin on the chest or tummy (abdomen). The upper face (including an eye) is also a common site.

The pain is a localised band of pain. It can be anywhere on your body, depending on which nerve is affected. The pain can range from mild to severe. You may have a constant dull, burning, or gnawing pain. In addition, or instead, you may have sharp and stabbing pains that come and go. The affected area of skin is usually tender.

The rash typically appears 2-3 days after the pain begins. Red blotches appear that quickly develop into itchy blisters. The rash looks like chickenpox but only appears on the band of skin supplied by the affected nerve. New blisters may appear for up to a week. The soft tissues under and around the rash may become swollen for a while due to inflammation caused by the virus. The blisters then dry up, form scabs and gradually fade away. Slight scarring may occur where the blisters have been.

An episode of shingles usually lasts 2-4 weeks. In some cases, there is a rash but no pain. Rarely, there is no rash but just a band of pain. You may also feel you have a high temperature (feel feverish) and feel unwell for a few days.

Is shingles contagious?

You can catch chickenpox from someone with shingles if you have not had chickenpox before. But most adults and older children have already had chickenpox and so are immune from catching chickenpox again. You cannot get shingles from someone who has shingles.

The shingles rash is contagious (for someone else to catch chickenpox) until all the blisters (vesicles) have scabbed and are dry. If the blisters are covered with a dressing, it is unlikely that the virus will pass on to others. This is because the virus is passed on by direct contact with the blisters. If you have a job, you can return to work once the blisters have dried up, or earlier if you keep the rash covered and feel well enough. Similarly, children with shingles can go to school if the rash is covered by clothes and they do not feel unwell.

Pregnant women who have not had chickenpox should avoid people with shingles. Also, if you have a poor immune system (immunosuppression), you should avoid people with shingles. (See below for a list of people who have a poor immune system.) These general rules are to be on the safe side, as it is direct contact with the rash that usually passes on the virus.

Can other people catch it?

This one is confusing! Here's the deal. You can catch chickenpox from other people, but you can't catch shingles from other people. You only get shingles from a reactivation of your own chickenpox infection in the past.

So, if you have shingles, and you come into contact with somebody else, they cannot "catch" your shingles. But if they have never had chickenpox, it is possible that they could catch chickenpox from you. (And if you had chickenpox and came into contact with somebody else who had never had chickenpox, they could catch chickenpox. But they couldn't "catch" shingles from your chickenpox).

To put it another way, no, you don't "catch" shingles. It comes from a virus hiding out in your own body, not from someone else. But if you have shingles, you may be infectious, as it is possible for people to catch chickenpox from you.

Only people who have never had chickenpox are likely to be at risk of catching chickenpox from your shingles. People who have had chickenpox should be immune from catching it again. If the rash is in a covered area of skin, the risk of anyone with whom you are not in close contact catching chickenpox is very low.

Causes of shingles

Most people have chickenpox at some stage (usually as a child). The virus does not completely go after you have chickenpox. Some virus particles remain inactive in the nerve roots next to your spinal cord. They do no harm there and cause no symptoms. For reasons that are not clear, the virus may begin to multiply again (reactivate). This is often years later. The reactivated virus travels along the nerve to the skin to cause shingles.

In most cases, an episode of shingles occurs for no apparent reason. Sometimes a period of stress or illness seems to trigger it. A slight ageing of the immune system may account for it being more common in older people. (The immune system keeps the virus inactive and prevents it from multiplying. A slight weakening of the immune system in older people may account for the virus reactivating and multiplying to cause shingles).

Shingles is also more common in people with a poor immune system (immunosuppression). For example, shingles commonly occurs in younger people who have HIV/AIDS or whose immune system is suppressed with treatment such as steroids or chemotherapy.

Shingles treatment options

Two main aims of treating shingles are:

• To ease any pain and discomfort during the episode of shingles.
• To prevent, as much as possible, complications from developing.

General measures

Loose-fitting cotton clothes are best to reduce irritating the affected area of skin. Pain may be eased by cooling the affected area with ice cubes (wrapped in a plastic bag), wet dressings, or a cool bath. A non-adherent dressing that covers the rash when it is blistered and raw may help to reduce pain caused by contact with clothing. Simple creams (emollients) may be helpful if the rash is itchy.

Painkillers for shingles

Painkillers - for example, paracetamol, or paracetamol combined with codeine, or anti-inflammatory painkillers (such as ibuprofen) - may give some relief. Strong painkillers (such as oxycodone and tramadol) may be needed in some cases.

Some painkillers are particularly useful for nerve pain.

If the pain during an episode of shingles is severe, or if you develop postherpetic neuralgia (PHN), you may be advised to take:

• An antidepressant medicine in the tricyclic group: An antidepressant is not used here to treat depression. Tricyclic antidepressants, such as amitriptyline, imipramine and nortriptyline, ease nerve pain (neuralgia) separate to their action on depression; or
• An anticonvulsant medicine such as gabapentin or pregabalin: They also ease neuralgic pain separate to their action to control convulsions.

If an antidepressant or anticonvulsant is advised, you should take it regularly as prescribed. It may take up to two or more weeks for it to become fully effective to ease pain. In addition to easing pain during an episode of shingles, they may also help to prevent PHN. 

Antiviral medicines for shingles

Antiviral medicines include acyclovir, famciclovir and valaciclovir. An antiviral medicine does not kill the virus but works by stopping the virus from multiplying. So, it may limit the severity of symptoms of the shingles episode. It had also been hoped that antiviral medicines would reduce the risk of pain persisting into PHN. However, the research so far has shown that the current antiviral medicines taken during an episode of shingles do not seem to have much impact on the prevention of PHN. Further research is needed in this area to determine if newer antiviral drugs can prevent PHN.

An antiviral medicine is most useful when started in the early stages of shingles (within 72 hours of the rash appearing). However, in some cases your doctor may still advise you have an antiviral medicine even if the rash is more than 72 hours old - particularly in elderly people with severe shingles, or if shingles affects an eye.

Antiviral medicines are not advised routinely for everybody with shingles. For example, young adults and children who develop shingles on their tummy (abdomen) very often have mild symptoms and have a low risk of developing complications. Therefore, in this situation an antiviral medicine is not necessary. Your doctor will advise if you should take an antiviral medicine.


As a general rule, the following groups of people who develop shingles will normally be advised to take an antiviral medicine:

If you are over the age of 50: The older you are, the more risk there is of severe shingles or complications developing and the more likely you are to benefit from treatment.

If you are of any age and have any of the following:

• Shingles that affects the eye or ear.
• A poorly functioning immune system (immunosuppression - see later for who is included).
• Shingles that affects any parts of the body apart from the trunk (that is, shingles affecting an arm, leg, neck, or genital area).
• Moderate or severe pain.
• Moderate or severe rash.
• If prescribed, a course of an antiviral medicine normally lasts seven days.

Steroid medication for shingles

Steroids help to reduce swelling (inflammation). A short course of steroid tablets(prednisolone) may be considered in addition to antiviral medication. This may help to reduce pain and speed healing of the rash. However, the use of steroids in shingles is controversial. Your doctor will advise you. Steroids do not prevent PHN.

Diagnosis

Are there any tests for shingles?

Tests are not usually done for shingles. The rash can be recognised by its typical pattern and symptoms.

Should I see a doctor?

It is usually worth seeing a doctor to be certain about the diagnosis and to see if you need treatment or not. Ideally you should see a doctor as soon as possible after the rash appears. This is because the sooner anti-shingles treatment is started, the more effective it is. In particular, it is not usually given if the rash has already been present for more than three days.

The rash of shingles can be very painful. So even if the doctor doesn't think you need an anti-shingles medicine, they may be able to give you stronger painkillers than those you can buy over the counter from the chemist.


The doctor is likely to consider anti-shingles treatment if:

• You are over 50 years old.
• You have immunosuppression. That is, your immune system is not working as well as normal. This could be due to treatment (such as chemotherapy, steroids, or immunosuppressant medicines used after organ transplants or for severe arthritis) or illness (such as HIV/AIDS or certain cancers).
• The rash involves your eye or your ear.
• The rash covers a wide area or is very painful.

So, if any of these apply to you, see a doctor as soon as possible after the rash appears.

What if I have shingles and a poor immune system?

If you have a poor immune system (immunosuppression) and develop shingles, then see your doctor straightaway. You will normally be given antiviral medication whatever your age and will be monitored for complications.


People with a poor immune system include:

• People taking high-dose steroids. (This means adults taking 40 mg prednisolone (steroid tablets) per day for more than one week in the previous three months. Or, children who have taken steroids within the previous three months, equivalent to prednisolone 2 mg/kg per day for at least one week, or 1 mg/kg per day for one month.)
• People on lower doses of steroids in combination with other immunosuppressant medicines.
• People taking anti-arthritis medications which can affect the bone marrow.
• People being treated with chemotherapy or generalised radiotherapy, or who have had these treatments within the previous six months.
• People who have had an organ transplant and are on immunosuppressive treatment.
• People who have had a bone marrow transplant and who are still immunosuppressed.
• People with an impaired immune system.
• People who are immunosuppressed with HIV infection.

Complications

What complications are there from shingles?

Most people do not have any complications. Those that sometimes occur include the following.

Postherpetic neuralgia (PHN)

This is the most common complication. It is where the nerve pain (neuralgia) of shingles persists after the rash has gone. This problem is uncommon in people aged under 50. However, up to 1 in 5 people with shingles, over the age of 60, have pain that lasts more than a month. The older you are, the more likely it will occur. The pain usually eases gradually. However, in some people it lasts months, or even longer in a few cases.

Scaring and pigmentation

As a result of inflammation, permanent skin damage may ensue. This could lead to both scaring and pigmentation changes, especially in dark skinned people. Areas of de-pigmentation, resulting in patches of pink skin with the absence of natural skin pigments, or hyper-pigmentation, causing darkly stained regions, can be a common problem.

Skin infection

Sometimes the rash becomes infected with germs (bacteria). The surrounding skin then becomes red and tender. If this occurs, you may need a course of medicines called antibiotics.

Eye problems

Shingles of the eye can cause inflammation of the front of the eye. In severe cases it can lead to inflammation of the whole of the eye which may cause loss of vision.

Weakness

Sometimes the nerve affected is a motor nerve (ones which control muscles) and not a usual sensory nerve (ones for touch). This may result in a weakness (palsy) of the muscles that are supplied by the nerve.

Various other rare complications

Examples are infection of the brain by the varicella-zoster virus or spread of the virus throughout the body. These are very serious but rare. People with a poor immune system (immunosuppression) who develop shingles have a higher than normal risk of developing rare or serious complications. (For example, people with HIV/AIDS, people on chemotherapy, etc.)

Treatment

Is there a shingles vaccine?

There is a vaccine against the varicella virus which has been used routinely in the USA since 1996 to protect children against chickenpox. It is not given routinely in the UK but is available for prescription on the NHS if the doctor thinks it is needed. The vaccine has reduced the incidence of chickenpox in the USA. If fewer people get chickenpox, then fewer people will get shingles later in life.

What about immunisation for older people?

The vaccine against the varicella-zoster virus has been shown in large studies to be effective in reducing the risk of older people developing shingles. The vaccine has been shown to be safe with very few side-effects.

The shingles vaccine is a one-off injection, given in your upper arm, usually by your practice nurse. Most people do not get side-effects from the vaccine, but you may get a red, sore or itchy area around the injection site. Some people may feel some other side-effects, such as a temperature, aches and pains, a rash or headache. Other side-effects are rare.

Other than the vaccine, there is no way of preventing shingles for somebody who has had chickenpox in the past.

About the author

Dr Mary Harding

BA, MA, MB BChir, MRCGP, DFFP

Mary qualified at Cambridge in 1989. She joined EMIS as an author in 2013. Mary is a part-time, salaried GP at The Village Surgery, Wheathampstead and previously for 12 years in Welwyn Garden City. Mary is also an appraiser and Senior Appraiser for NHS England, in the Central Midlands area team.

Recommended websites

For further reading go to:

• Shingles - The American Academy of Dermatology
• Shingles and Postherpetic Neuralgia

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