Herpes Zoster (Shingles)
October 26, 2012
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 chicken pox 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.
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 immune restoration syndrome (see Fact Sheet 483).
Having HIV increases the risk of complications from shingles. These include pain (post herpetic neuralgia.) Also, if you notice any blurred vision, see your health care provider immediately. Also, as more people with HIV reach higher ages, they may be more likely to develop shingles.
How Is It 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 anything 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 of treatment for pain.
Antiviral drugs: The standard treatment for shingles is the drug acyclovir, which can be given orally (in pill form) or intravenously in more severe cases. Two newer 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.
Nerve blockers: Doctors often prescribe various pain medications for people with shingles. Because the pain of shingles can be so intense, researchers have looked for other ways to block the pain. 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. A newer skin treatment is Qutenza. It is a highly concentrated form of capsaicin. It is applied in a doctors office for 60 minutes. One application can provide 3 months of relief.
Other Pain Medications: 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. Pregabalin is an epilepsy medicine also used for pain after shingles.
Can Shingles Be Prevented?
Currently, there is no way to predict an outbreak of shingles.
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.
Zostavax, a shingles vaccine developed by Merck, has been approved by the FDA. An initial study in people with HIV showed that Zostavax was safe and effective.
The Bottom Line
Shingles is an unpredictable, very painful disease. It is caused by a re-activation of the virus that causes chicken pox. Although not directly linked to HIV, shingles seems to occur more frequently in people with AIDS.
Although shingles may disappear within a couple of weeks, severe pain may continue for several months.
A shingles vaccine has been approved by the FDA. An initial study in people with HIV found that Zostavax was safe and effective.
The disease has been treated with acyclovir, taken five times daily, or given intravenously in severe cases. Two newer drugs, famciclovir and galaciclovir, seem to be more effective against the pain of shingles and need to be taken only three times each day.
It can be very difficult to deal with the pain of shingles. A newer treatment is an anesthetic patch that can be applied directly to the skin.
This article was provided by AIDS InfoNet. Visit AIDS InfoNet's website to find out more about their activities and publications.