- Shingles, also known as herpes zoster, is a painful rash caused by the chickenpox virus (varicella-zoster virus, or VZV).
- Most children are infected with VZV and the virus is never eliminated from the body.
- The elderly, and people with compromised immune systems, including people with HIV infection, are at greater risk of developing shingles.
- Shingles appears as a strip of small blisters on reddened skin on the body or face.
- Shingles lesions in the eye can result in loss of vision.
- There is no known cure for shingles, but treatment soon after the outbreak can shorten the duration and minimise the complications.
What is shingles?
Shingles, also known as herpes zoster, is a painful rash caused by the reactivation of the chickenpox virus (varicella-zoster virus, or VZV). The rash appears as a strip of small blisters on an area of reddened skin, usually on one side of the chest, back or face.
What causes shingles?
Most children are infected with the varicella zoster virus (VZV), which causes chickenpox. The body fights the infection in childhood, but is never totally rid of VZV, which then lies hidden in nerve cells near the brain or spine. In later adult life, or in people with compromised immune systems, VZV can be reactivated, leading to a case of shingles. The reason why VZV is reactivated is not well understood.
It is possible for VZV to be transmitted through direct contact with shingles blisters. Once the blisters are dry and scabs have formed, the virus is no longer active. It is far easier to be infected with VZV when coming into casual contact with a person who has an active case of chickenpox. In this instance, the virus is present in the chickenpox blisters as well as in the blood and lungs of the infected person. People with HIV infection who have not been infected with VZV should avoid contact with people who have shingles or an active outbreak of chickenpox.
How does shingles affect people with HIV/Aids?
A weakening of the immune system can precipitate an outbreak of shingles. For this reason, people with HIV infection are at greater risk of developing shingles. In the later stages of Aids there is a greater chance of repeated outbreaks and it may also take longer for the shingles lesions to heal, making them more vulnerable to bacterial infections.
Symptoms and signs of shingles
The first sign is a sensation on the skin, varying from tingling to severe pain or a burning feeling, limited to the body area where the rash will appear. Within two to three days after these symptoms are felt, the skin reddens and small blisters appear. Eventually the numerous blisters turn cloudy, break and crust, before finally disappearing. The rash lasts for 10 to 14 days before the blisters start to heal. Permanent skin discolouration can occur in the area of the rash.
The rash rarely affects more than one area at a time. Pain accompanying the blisters can range from very severe to mildly irritating, and sometimes the pain can persist long after the rash has cleared. Lymph glands in the surrounding area may be swollen and painful to the touch. In some cases, pain is experienced but no rash appears.
Complications associated with shingles
Although VZV very seldom becomes reactivated in more than one nerve at a time, in severe cases of weakened immune systems the rash can spread over a wide area of skin.
It is also possible for the virus to infect the blood and to spread to internal organs. However, even in people with HIV infection, this complication is rare. If shingles appears on the face, particularly close to the inner corner of the eye, care must be taken against eye damage. Opthalmic zoster, where shingles affects the eye, can result in a loss of vision. This potentially dangerous condition can also spread to the brain.
One of the most common complications associated with shingles is post-herpetic neuralgia: a deep pain that can last for months, even years, after the rash has cleared. The sensation of pain is caused by damage to the nerve during shingles. In the case of people with HIV infection, this complication does not occur frequently.
Shingles lesions are vulnerable to bacteria and must be kept clean to prevent skin infections.
How is shingles diagnosed?
Usually a diagnosis of shingles is made on the grounds of the tell-tale rash and characteristic symptoms. On occasion, the infection can appear in a way that makes the diagnosis difficult. For example, the pains that accompany shingles can be intense and mistaken for a heart attack or backache. In some cases, the pain is present but the rash never appears. In these instances, a blood test or a skin biopsy can help to confirm a diagnosis of shingles.
How is shingles treated?
There is no known cure for shingles, but treatment soon after the outbreak can shorten the duration and minimise the complications. Treatment works best if it is started within three days of the outbreak. Antiviral drugs can help the rash to heal faster and reduce the severity of post-herpetic neuralgia. However, these drugs will not eliminate VZV from the body. Early treatment with antiviral medication such as Famvir or Zelitrex may shorten the course of the disease. Regular painkillers are usually needed.
Medication should be taken until all the blisters have dried up and scabbed over. The healing process can take up to four weeks for people with compromised immune systems. Hospitalisation may be necessary for drugs to be given intravenously, as in the case of ophthalmic zoster or where shingles has spread to internal organs.
The following can be helpful when the rash is still active:
- wearing light clothing or keeping the affected area open
- keeping the rash clean by washing the affected area with soap and water
- bandaging the rash at night to avoid touch irritation
- applying ice to relieve symptoms