Family doctor

Overview:

• Shingles is also known as herpes zoster
• It is caused by a reactivation of the same virus that causes chicken pox
• Shingles is more common among those over 60
• Shingles is contagious and can cause chickenpox in those who haven't had it
• Symptoms include pain along a nerve followed by a red rash with small blisters
• The blisters break and then crust over and heal
• The illness can last up to three weeks
• Shingles can lead to a painful condition called post-herpetic neuralgia
• Anti-viral drugs can reduce the pain of shingles and the incidence of neuralgia

What is it?

Shingles is also known as herpes zoster and is caused by the same virus that is responsible for chickenpox.

The chickenpox virus lies dormant in the body for many years before it reactivates and forms shingles. It is not known why it reactivates, but it may be caused by pressure on the nerves, an operation, and emotional stress. In most people there is no obvious underlying trigger to an attack.

Usually shingles only appears once in a lifetime. It is more common in people over the age of 60, and those who caught chickenpox before the age of one.

It may also appear as a complication of HIV/AIDS, leukaemia and other cancers.

It is believed that shingles can be an early sign of HIV infection in young Africans.

The condition affects about 10 to 20 percent of the population and nearly half of over 80 year olds.

The illness is expected to become more common because of an aging population.

Shingles is contagious and can cause chickenpox in people who have not already had it.

What are the symptoms?

The illness starts with a pain or burning sensation along a nerve, with the appearance of a rash at the same site about two days later.

The rash looks like red patches of skin which small blisters that are similar to chicken pox. The rash spreads for about four days before the blisters break and form small sores, which dry and crust over and heal. The crusts are shed in between two and three weeks. A person is no longer infectious after the blisters have crusted over.

The trunk, chest, neck and face are the areas most commonly affected by the shingles rash. It often appears along a branch of a nerve in a belt or in clusters. It normally only appears on one side of the body.

Sometimes more than one nerve is involved, and sometimes a rash never appears.

Laboratory tests can confirm shingles, however, usually the appearance is so typical that doctors can recognise it.

The most common complication from shingles is post-herpetic neuralgia, an extremely painful and debilitating condition characterised by pain at the shingles site which continues for more than one month after the initial illness. The pain may continue for years afterwards. Early treatment with medications which modify pain perception (e.g. amytriptiline), may reduce post herpetic neuralgia.

About 30 percent of people over 40 years with shingles will get post-herpetic neuralgia.

Other complications include bacterial infections, and rarely blindness if the eye is affected. Shingles on the face can lead to Ramsay Hunt syndrome, which causes hearing loss, loss of taste buds, and facial paralysis.

What can be done to help?

Taking anti-viral drugs within the first few days of the appearance of the rash can help to reduce the length of the illness and may help prevent the development of post hepatic neuralgia.

These drugs are not recommended for everyone. They may be prescribed for those over 50, people with a facial rash, and those with weak immune systems.

Drug treatment is unhelpful if it sought later than three days after the appearance of the rash.

Rest and the use of the paracetamol is the main treatment if anti-viral drugs are not prescribed. The shingles rash should be kept covered and dry.

There is debate over the use of steroids to help ease shingles pain.

Several medications can be used to treat post-herpetic neuralgia, including antidepressants and anti-seizure drugs.

How can it be prevented?

There is a vaccine available that can prevent chickenpox. People who have not had chickenpox cannot get shingles.

Future trends

Researchers are studying the chickenpox virus to establish why it can lie dormant for decades and then be reactivated in the shingles form.

Scientists are also studying how long the Varilrix vaccine (chicken pox vaccine) protects against the illness.

Getting help

Your doctor will be able to help. It is important to get help early if severe pain is persisting.