This painful condition is more likely to attack as you age, and it can raise your risk for chronic pain, stroke, and other problems.
A common childhood illness can return to cause serious health issues later in life. Shingles is a disease caused by the same varicella-zoster virus that triggers childhood chickenpox.
"All adult Americans who were exposed to chickenpox can develop shingles. In fact, one in three is predicted to get shingles at some point," says Dr. Anne Louise Oaklander, director of the Nerve Unit at Harvard-affiliated Massachusetts General Hospital.
After chickenpox has disappeared, the virus lies dormant in nerve cells near the spinal cord and brain. Years later, as your immunity weakens during normal aging or from illness or medications, the virus often re-emerges.
It travels along a nerve to activate a one-sided rash affecting the skin connected to that nerve. The most common areas are the chest, back, or belly, or above one eye.
Seek treatment right away
Although some rashes are mild, many cause severe pain and itching and leave scars. Over a few weeks, fluid-filled blisters can develop, break, and crust over. Some people also feel sick with slight fevers, headache, or fatigue.
Until recently, there was little public concern about shingles, and most people had the mistaken impression that, like poison ivy, it was a nuisance rash that faded on its own. "But in fact a shingles rash should alert people, especially in middle or old age, to seek immediate medical help from their doctor," says Dr. Oaklander.
One of three antiviral drugs—acyclovir (Zovirax), valacyclovir (Valtrex), or famciclovir (Famvir)—can shorten a shingles attack and reduce the risk of serious damage. "But you must begin them right away," says Dr. Oaklander.
Possible long-term damage
The older you are, or if you do not get prompt antiviral medications, the more likely you are to be left with long-term problems. These include the following:
Lasting pain. Pain that lingers in the area of a healed shingles rash is called postherpetic neuralgia. Pain can last months and sometimes even over a year. Treatments include anesthetic patches that numb the painful area, pills such as nortriptyline (Pamelor) and gabapentin (Neurontin), or opioid pain medications.
Damage to vision. Pain and rash near an eye can cause permanent eye damage and requires an ophthalmological exam.
Damage to hearing or balance. When the nerve to the ear is affected, it can permanently damage hearing or balance and cause facial problems.
Confused thinking. A reactivated shingles virus also travels inward toward the brain and spinal cord. It is rare, but this may cause inflammation known as encephalitis that causes flu-like symptoms and confused thinking.
Stroke and heart attacks. A study published Dec. 15, 2015, in PLOS Medicine, which tracked 67,000 shingles patients ages 65 or older, found that stroke risk more than doubled in the first week after diagnosis. Risk for heart attacks was also higher in the first three months.
Vaccination is effective at preventing shingles. The CDC recommends immunization for almost all people ages 60 or older, regardless of whether they had chickenpox in their youth or have had shingles before.
The vaccine that prevents chickenpox in children was used to develop Zostavax, which protects against shingles. "It reduces the risk of getting shingles by about one-half, and shingles rashes that still develop are slightly less likely to cause postherpetic neuralgia or other serious complications," says Dr. Oaklander. "The earlier you are immunized, the better, since vaccines are less effective in older people."
However, people with especially weak immune systems—such as those with cancer or undergoing immunosuppressive treatments—should avoid Zostavax, since the vaccine contains a weakened form of the live virus.
Since Zostavax has only been available since 2006, it is still not yet clear if a single vaccination offers lifelong protection, but no booster is recommended at this time.
Possible new shingles vaccine on the way
A new vaccine called HZ/su may be helpful for older adults. A study in the May 28, 2015, New England Journal of Medicine found that among more than 15,000 participants, the vaccine was 97.2% effective among adults ages 50 or older, and 97.9% for those ages 70 or older. And since HZ/su is not made from a live virus, it is safe for people with weak immune systems. The vaccine needs to undergo further testing before it can be submitted for FDA approval, which may happen as early as this year.