Shingles, or herpes zoster, is a viral infection that affects mainly the skin and nerves. The virus is called the herpes varicella-zoster virus (VZV). Varicella is the medical name for chicken pox and zoster for shingles. The reason for the double name is that this single virus causes both chicken pox and shingles.
Chicken pox is largely a childhood disease, though some will become infected for the first time later in life. After the chicken pox infection is fought off by the body’s immune system, the virus will lie dormant in nerve cells in the body. As we get older and our immunity against the virus weakens, the infection can reappear.
However, unlike the chicken pox infection, which gives the characteristic itchy rash all over the body, the re-infection of shingles will only be seen in a localized area of the body. Each nerve supplies only one region of the skin (called a dermatome). Virus residing in that nerve will cause symptoms along that nerve’s distribution. So the rash and symptoms of shingles follow a band-like area, wherever that nerve supplies.
The symptoms of shingles usually begin with changes in sensation: Burning, itching, tingling or pain in the skin. The rash may not be evident right away, sometimes for several days. This makes it difficult in many cases to diagnose shingles accurately and quickly. Once the rash appears, it’s more straightforward.
The rash is usually red-based and has small clustered blisters. The band-like rash is seen only on one side of the body. The most common site is on the trunk. Like chicken pox, these skin lesions usually crust and scab over within a few days. Since shingles is a viral infection, some will experience other general viral symptoms including malaise, fever and aches. In most cases, symptoms resolve in 10 to 14 days.
Complications of shingles include local skin infection, involvement of the eyes in ocular shingles and chronic pain in the nerve area infected by the virus. Up to 20 percent of individuals with shingles will develop this chronic pain syndrome called “post herpetic neuralgia.” This is a constant burning pain that can last for months after the initial infection.
Treatment of shingles is aimed at resolving the acute infection, relieving any pain associated with the infection and preventing post herpetic neuralgia. Antiviral medications taken within the first 72 hours of infection onset have been shown to decrease the duration of the rash and severity of the pain. These drugs include acyclovir, famciclovir (Famvir) and valacyclovir (Valtrex). These medicines, when taken during an acute infection, may prevent the development of post herpetic neuralgia, as well.
Other medicines used to treat shingles include anti-inflammatory and pain medicines. These include over-the-counter drugs such as Tylenol or ibuprofen, or stronger prescription medicines, such as narcotic pain killers. Topical pain and itch lotions or gels can also be helpful. These include capsaicin (Zostrix) and calamine.
The varicella vaccine, begun in 1995, has decreased cases of both the chicken pox and shingles. It is given between the ages of 19 to 35 months with a booster prior to starting school. The shingles vaccine was licensed in 2006. It is recommended for the prevention of herpes zoster for those age 60 years and older.
The content in this column is for informational purposes only. Consult your physician for appropriate individual treatment. Dr. Reynolds practices Family Medicine in Chesterfield.