Dear Doctor Column, June 12, 2006
Shingles Vaccine Safe for Older Adults
Question:
One of my friends had a painful case of shingles last year, and I am thinking about getting the recently approved vaccine. I’m 65 years old and in good health. Is the shingles vaccine safe for older people? Do I really need this shot?
Answer:
The Food and Drug Administration approved Zostavax, the first shingles vaccine, in May 2006. Doctors will probably begin offering the vaccine by midsummer, although most insurance companies do not yet cover its cost, which will run between $150 and $200.
Zostavax cuts the risk of developing shingles in half. The condition, a painful outbreak of rash and blisters that is often difficult to treat and can result in long-term pain and disability, is caused by varicella-zoster virus, the same virus that causes chickenpox. After an attack of chickenpox, the virus settles in nerve tissue where it lies dormant, usually for years. Shingles is unpredictable and can crop up at anytime in anyone who has had chickenpox. The disease is much more common in adults older than 60 years than in younger individuals. People’s immunity to the virus declines with age, making them vulnerable to its reactivation as shingles. Once the virus begins to reproduce, it travels along a nerve to the skin, causing the characteristic rash.
Shingles begin with burning or tingling pain, and sometimes itching, on one side of the face or body. The virus usually reaches nerve endings in the skin 2 to 5 days after the first symptoms, and a painful rash of clear fluid-filled blisters appears over reddened skin. During the next 3 to 5 days, the rash spreads in the band-like area of skin supplied by the affected nerve. The blisters dry up in a few days, forming crusts that fall off in 3 to 5 weeks. In most individuals, the pain, which is often intense, resolves along with the rash. But, in some people, the virus damages sensory nerves, which continue sending pain impulses even after skin lesions heal — a condition called postherpetic neuralgia.
The older people are when they have an outbreak of shingles, the more likely they are to experience prolonged pain, which can last for several months, and more rarely, for years. Some people feel a deep constant aching, as though the rash were still there, while others describe an electric shock type of pain that lasts for a few seconds at a time. A common complication of shingles is a condition called allodynia. People with allodynia can feel pain at the lightest touch of clothing or a breeze.
Most people have only one attack of shingles in their lifetime, but an unfortunate 4% have multiple episodes. Shingles is much less contagious than its precursor, chickenpox, although people with an active shingles rash can pass the virus to individuals who have never had chickenpox or the chickenpox vaccine. The blisters shed varicella-zoster virus, which can infect people who lack immunity to the virus — this causes chickenpox, not shingles. You can reduce the risk of infection by keeping the rash covered with a bandage. People with shingles should avoid close contact with individuals who have never had chickenpox or the chickenpox vaccine — especially infants, children, and pregnant women — until their blisters are completely dry.
The key to successful therapy is beginning medication as soon as possible. Acyclovir, famciclovir, and valacyclovir are prescription antiviral drugs that attack herpes viruses such as varicella zoster. When begun within 72 hours after the rash appears, these drugs can speed healing and may prevent or shorten the duration of postherpetic neuralgia. Your doctor also can prescribe topical and oral pain relievers.
The problem with antiviral treatment is that many people don’t recognize their symptoms as shingles and get to the doctor during the first 3 days of the rash’s onset. Starting antivirals more than 3 days after an outbreak limits their beneficial effects on healing and prevention of postherpetic neuralgia. There are few effective treatments for postherpetic neuralgia and patients often have to take a combination of medications to get some measure of relief.
Preventing shingles is preferable to treating the condition or its complications. The shingles vaccine’s approval comes in the wake of a large well-conducted study with about 40,000 participants, all of whom were aged 60 years and older (average age, 69 years). Half the participants received placebo, while the others got a live virus vaccine — a much more potent formulation of the chickenpox vaccine already in use in the United States. The vaccine boosts immunity to the virus, reducing shingles incidence by 50%.
Most vaccinated individuals who got shingles experienced a shorter, less painful outbreak than those who received placebo and also were less likely to develop postherpetic neuralgia. Zostavax was most likely to prevent shingles in people aged 60 to 69 years. For those people who got shingles despite the vaccine, those aged 70 years and older had the greatest reductions in long-term pain.
The vaccine, approved only for individuals who are older than 60 years, seems safe and well tolerated. Zostavax is given as a one-time injection, usually in the upper arm. Side effects are mild and include headache and redness, pain, tenderness, and swelling at the injection site. The vaccine hasn’t been studied in younger people, or in those with compromised immune systems. People with immune systems weakened by cancer, HIV, active tuberculosis, or immunosuppressive drugs such as steroids, should not get the shingles vaccine. In addition, women who are pregnant or may become pregnant should not have the vaccine. If you have ever had an allergic reaction to a vaccine, you should tell your doctor before getting Zostavax.
Because Zostavax is a live vaccine, meaning it contains living varicella-zoster virus, it is possible for the injection site to shed virus and infect individuals without immunity. If any of your close contacts include people who may be pregnant or have never had chickenpox or the chickenpox vaccine, make sure to discuss this with your doctor before vaccination, so he can explain how to prevent spread.