WHAT IS SHINGLES? Shingles is a very painful disease caused by the same herpes virus that causes chicken pox (varicella zoster virus). Like other herpes viruses, the varicella-zoster virus has an initial infectious stage, (chicken pox) followed by a dormant stage. Then, with no warning, the virus becomes active again. About 20% of people who have had chickenpox will eventually develop shingles.
This reactivation of the virus is most likely to occur in people with a weakened immune system. This includes people with HIV disease, and anyone over 50 years old.
Herpes zoster lives in nerve tissue. Outbreaks of shingles start with itching, numbness, tingling or severe pain in a belt like pattern on the chest, back, or around the nose and eyes. In rare cases, herpes can infect the facial or eye nerves. This can cause outbreaks around the mouth, on the face, neck, and scalp, in and around the ear, or at the tip of the nose.
Shingles outbreaks are almost always on just one side of the body. Within a few days, a rash appears on the skin area related to the inflamed nerve. Small blisters form and fill with fluid. Later they break open and develop crusty scabs.
If the blisters are scratched, someone with shingles might develop a skin infection. This could require treatment with antibiotics and might cause scars.
In most cases, the rash goes away within a few weeks, but in some cases, severe pain can last for months or even years. This condition is called "post herpetic neuralgia."
SHINGLES AND HIV
Shingles is not one of the infections that leads to a diagnosis of AIDS.
A recent study of people with HIV found the highest rates of shingles in:
- gay or bisexual men
- those younger than age 29
- people with less than 500 T-cells
- whites rather than blacks or Hispanics
Shingles can occur in people with HIV shortly after they start taking strong antiviral medications. These cases of shingles are believed to be a sign of a recovering immune system.
HOW IS SHINGLES TRANSMITTED?
Shingles can only occur after someone has had chickenpox. If someone who has already had chickenpox comes into contact with the fluid from shingles blisters, they will not "catch" shingles. However, people who have not had chickenpox could become infected with herpes zoster and develop chickenpox. They should avoid contact with the shingles rash or with any materials that may have touched the shingles rash or blisters.
HOW IS SHINGLES TREATED?
Several types of drugs are used to treat shingles. They include anti-herpes drugs, and several types treatments for pain.
Anti-herpes drugs: The standard treatment for shingles is the drug acyclovir, which can be given orally (in pill form) or intravenously in more severe cases.
Recently, two new drugs have been approved for the treatment of shingles: famciclovir and valacyclovir. Both famciclovir and valacyclovir are taken three times each day, compared to five times for acyclovir. All of these drugs work best when they are started within the first three days after the shingles pain begins.
Injections of anesthetic drugs and/or steroids are being studied as nerve blockers. These can be injected either into peripheral nerves, or into the spinal column (central nervous system.)
Skin Treatments: Several creams, gels and sprays are being studied. These provide temporary relief from pain. Capsaicin, the chemical that makes chili peppers hot, has shown good preliminary results. In addition, in 1999 the FDA approved a patch form of the anesthetic lidocaine. The patch, called Lidoderm, provides pain relief for some people with shingles. Because it is applied to the skin, it has less risk of side effects than pain medications taken in pill form. For more information, see the Endo Laboratories web site at http://www.lidoderm.com/
Other Pain Medications: A new drug, pregabalin, was approved in late 2004 but is not yet available. Some drugs normally used to treat depression, epilepsy, or severe pain are sometimes used for the pain of shingles. These can have a variety of side effects. Nortriptyline is the antidepressant most frequently used for shingles pain.
CAN SHINGLES BE PREVENTED?
Currently, there is no way to predict an outbreak of shingles, and there is no medication approved to prevent it.
However, researchers have shown that giving older people a stronger form of the chicken pox vaccine used for children can boost the type of immunity believed necessary to hold the virus in check. The researchers hope to show that this increased immunity will result in a lower risk of shingles in later life. Merck is developing a shingles vaccine. In a large clinical trial, it reduced shingles illness by about 60%. However, it was only tested in adults over age 60. People wih weakened immune systems were excluded so its value for people with HIV is unknown.
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