The shingles vaccine, Zostavax, is highly recommended for those over sixty years old to prevent an attack of shingles. Shingles (herpes zoster) is a painful infection resulting from the reactivation of a chicken pox infection years earlier. The risk of getting shingles starts to increase after the age of fifty. The clinical study that established the recommendation only tested adults over sixty. If a person is unsure whether they ever had chicken pox, a test called a varicella titer can be run.
Shingles and Chicken Pox are both caused by an infection with the varicella-zoster virus. Shingles is a reoccurrence of the initial chicken pox virus. During a chicken pox infection, the virus spreads throughout the bloodstream. Besides the typical blisters, the virus infects nerve cells of the spine or cranium. There it can stay in a sleeping state for many years. It may never again cause any symptoms or it may reactivate through the nerve fibers leading to the skin.
The sores from shingles resemble chicken pox but are almost always on just one side of the body where the infected nerve fibers are. Early symptoms can include fever, chills, diarrhea, nausea or difficulty urinating. Sometimes there is a tingling or itching feeling in one area of the skin. After a few days, little fluid-filled blisters in the midst of a larger reddish skin area develop. The area of involvement is highly sensitive to touch.
Generally the blisters will dry over, creating scabs within five days after they first appear. The blisters do contain the live virus and can infect susceptible people with chicken pox. Usually an attack of shingles confers immunity for life, although perhaps five percent of individuals can have another attack. In a small number of cases, more prevalent with increasing age, there can be chronic pain in the affected area, called post-herpetic neuralgia. This may last weeks, months, or even years.
The shingles vaccine is not 100 percent effective. In a test of individuals 60 years and older, it prevented shingles approximately 50 percent of the time. The vaccine did reduce both the pain of the initial rash and, where post-infection pain occurred, it lessened the symptoms. The treatment also can be given to those who have had an attack of shingles to ward off a reoccurrence, but should not be given during an active episode. The vaccine is recommended by the Centers for Disease Control for those over sixty because the aftereffects of an infection are more severe in this age group.
Shingles vaccine is not recommended for anyone allergic to gelatin, neomycin, or any other ingredient in the vaccine; a weakened immune system; receiving medical treatment that can weaken the immune system such as chemotherapy or steroids; have a history of leukemia or lymphoma; have active tuberculosis or women either pregnant or trying to get pregnant. Side effects are reported to be mild and typically limited to redness and possibly some slight swelling near the injection site, tenderness or a headache.