Definition Shingles, or herpes zoster, is a painful rash of blisters that develops due to the virus that causes chickenpox.
What is going on in the body? A primary, or first time, infection with a virus called the varicella-zoster virus causes chickenpox. After someone recovers from chickenpox, the virus remains quiet, or dormant, in nerves. The infection can reactivate for various reasons later in life and this is called shingles.
What are the signs and symptoms of the infection? Shingles symptoms are usually limited to a small area of the body. This area is usually a small strip of skin on one side of the chest or abdomen. In some cases, the face can be involved, and this may cause an eye infection. The first symptoms are usually related to sensation. People may experience pain, numbness, tingling, or itching. Pain usually occurs at some point, and can be quite severe. This is usually followed by the development of groups of blisters. The areas around the blisters are often quite painful. The pain can be severe and last for weeks. Pain is usually much less severe in children.
What are the causes and risks of the infection? The cause of this condition is a reactivation of the chickenpox virus. Most people in Australia are infected with this virus. Weakness of the immune system may increase the risk of developing shingles. In people with weakened immune systems, infection can be very serious. In these people, the virus can spread all over the body, causing infection in the liver, lungs, and brain.
What can be done to prevent the infection? Primary varicella-zoster infection, or chickenpox, can be prevented. If chickenpox is prevented, shingles will not occur. Healthy children and some adults are given varicella vaccine, which prevents chickenpox. People with weak immune systems that have not had chickenpox may be given varicella zoster immune globulin (VZIG) if they are exposed to chickenpox.
How is the infection diagnosed? Usually the diagnosis of varicella-zoster is made by an interview with the person and a physical examination. The virus can be recovered from the blisters and identified with special tests. Blood tests can also be used to make the diagnosis in some cases if needed.
What are the long-term effects of the infection? In most cases, shingles goes away in a week or so and causes no long-term effects. However, some cases result in serious long-term effects. Eye infection may lead to serious eye problems, including blindness. Some people have chronic pain in the area of the blisters that doesn't go away for months or even years. Paralysis in the part of the body that had blisters occurs very rarely. In people with a weak immune system, the virus may cause a serious infection in the body. This may result in liver, brain, or lung damage, and possibly even death.
What are the risks to others? The virus can be spread to others if they are exposed to the fluid in the blisters. If people who have not received the varicella vaccine or been exposed to chickenpox before are exposed to someone with shingles, they may develop chickenpox.
What are the treatments for the infection? Acyclovir, valacyclovir or famciclovir can be used to treat shingles. Drugs for pain may also be needed. Eye infection usually requires the use of special eye drops to reduce inflammation.
What are the side effects of the treatments? Headaches and nausea may occur with the drugs used to treat shingles. These are usually taken as pills. People with severe infections may need acyclovir injected directly into the veins, which may cause kidney problems. Drugs for pain may cause stomach upset, allergic reactions or sleepiness. Exact side effects depend on the drug used. Eye drops can cause irritation and allergic reactions in the eyes.
What happens after treatment for the infection? In most cases, the shingles go away and people can return to normal activities. Pain may remain at the site of the healed blisters. Drugs for pain may be needed. People with eye infection may require long-term eye care from an opthalmologist.
How is the infection monitored? Most cases are monitored by the affected person at home. In severe infections, a person may need to be monitored in the hospital. Further monitoring in this setting would depend on the areas of the body that are affected by the infection. Those with eye infections usually need repeated eye examinations until the infection resolves.
Author: Danielle Zerr, MD Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request