What is the Varicella Zoster Virus?

Varicella Zoster virus (VZV) is one of the herpes viruses. That statement may confuse people because they frequently think of herpes as being a sexually transmitted disease or causing cold sores. Actually there are many different herpes viruses, and most people are fairly familiar with varicella zoster virus because it has infected so many people. It causes chickenpox, and also shingles, usually long after people have had an initial chickenpox exposure.

When people are not immune to varicella zoster virus, first exposure can mean developing a case of chickenpox. This is usually a mild illness, though an uncomfortable one. Sometimes there are complications when chickenpox occurs, and some people may develop encephalitis or other life-threatening complications. Though there are many who view chickenpox as a common and harmless infection of the varicella zoster virus, it does occasionally cause deaths. Moreover, it tends to greatly increase risk for people developing shingles at a later point.

Though the body initially responds to VZV infection with chickenpox, the end of the illness doesn’t signify the complete death of the virus. It can remain dormant in the body for many years and manifest as shingles, which causes a very painful skin rash. As people age, they not only are at risk for shingles but for a complication of it called postherpetic neuralgia.

Postherpetic neuralgia may last for months to years after the Varicella Zoster Virus has caused shingles, and it may first affect the skin, which may burn, or sting, and be painful to the touch. People may also get horrible headaches, have difficulty tolerating temperature changes, and sometimes the nerves that control the muscles become affected and may cause paralyzed muscles. Shingles and postherpetic neuralgia are unfortunate complications of the VZV that are well worth avoiding if possible.

There presently are several vaccines to fight Varicella Zoster Virus. Doctors now highly recommend that young children get the chicken pox vaccine. It may help prevent infection about 90% of the time, by giving a weakened version of VZV to patients. This helps them develop immunity to future contact with the virus.

There is also a shingles vaccine called Zostavax®. This is usually recommended for adults who are 60 or older, and who have had chickenpox. Zostavax® has been shown to be fairly effective in preventing shingles. Basically it’s action works to suppress a secondary expression of Varicella Zoster Virus. It’s not as effective as the chicken pox vaccine, but studies do show it prevents shingles about 50% of the time. It’s also been shown that Zostavax® may reduce the number of cases of postherpetic neuralgia and that it tends to overall shorten length of cases of shingles and any periods of postherpetic neuralgia thereafter.