Shingles

Shingles Media Backgrounder

The annual incidence of shingles is estimated to be around one million cases and about 25 percent of all Americans will get shingles in their lifetime. Virtually every adult in the United States has had chickenpox, and is therefore at risk of developing shingles. Moreover, since advanced age is a risk factor for shingles and the U.S. population is aging, incidence and prevalence can be expected to rise. Although shingles is most common in older people and those with weakened immune systems, it can affect younger persons, even children.

Pain and discomfort associated with shingles can be substantial. Its effect on quality of life and ability to function has been equated to the effects of congestive heart failure, myocardial infarction, diabetes and major depression. While medication is available to help reduce the severity and duration of the initial attack, there is no adequate therapy available for prevention or treatment of post-herpetic neuralgia (PHN), a painful and potentially long-term affect of shingles. Given the substantial morbidity associated with shingles and PHN, and the lack of effective treatments for the latter, prevention is desirable.

Vaccine against shingles approved by U.S. Food and Drug Administration

A vaccine for the prevention of shingles was approved in 2006 for use in persons 60 years of age and older. The Shingles Prevention Study, a collaborative trial by the Department of Veterans' Affairs, the National Institute of Allergy and Infectious Disease and Merck, enrolled over 38,000 adults 60 years of age and older and studied the effect of vaccination against re-activation of the varicella-zoster virus (VZV). At its first attack (usually in childhood), VZV causes chickenpox. While the clinical affect of chickenpox is self-limited, the virus remains in the body and, if it re-activates a second time, the clinical affect is shingles.

The vaccine reduced the burden of illness associated with shingles by 61 percent, the incidence of shingles by 51 percent and the incidence of PHN by 66 percent (p<0.001 for all results). Given its often intractable nature, reduction in PHN cases by two-thirds is perhaps the most important finding of the study.

Pain is often the first sign of shingles

Pain and paresthesia often precede eruption of the shingles rash by two to four days. Tingling and itching may also occur before the rash is evident. However, it is the appearance of the rash, usually unilaterally on the trunk or face, that simplifies shingles diagnosis. In fact, it is the appearance of the rash that gives shingles its name; shingles derives from the Latin cingulum, which means girdle or belt.

The rash usually begins as a cluster of bumps (papules) that develop into water-filled lesions (vesicles) and then into pus-filled lesions (pustules). Pustules eventually break, form crusty scabs and heal within about a month. For most people, shingles has run its course after the rash heals. However, for some, discomfort, itching and pain can linger.

PHN can continue for weeks, months or even years after the shingles rash has disappeared. PHN frequency and severity increase with increasing age. Unlike the pain associated with the acute phase of shingles, PHN is not easy to treat. Severe PHN can result in inability to perform normal daily activities, potentially leading to loss of independence, isolation and depression.

Medications may help shorten the course of shingles and control pain

Oral antiviral medications may help shorten the clinical course by hindering viral replication in nerve cells. Earlier initiation of antiviral therapy increases the likelihood of clinical response. The potential for positive effect of antiviral therapy is higher when new lesions are still forming.

During the acute phase of the disease, over-the-counter pain killers may be sufficient. More severe pain may require addition of prescription medications including opioids and other controlled products.

The herpes zoster vaccine (Zostavax™) should not be administered to anyone with a history of anaphylactic reaction to gelatin, neomycin or any component of the vaccine. This live vaccine should not be given to anyone with a weakened immune system caused by treatments such as radiation, corticosteroids, or due to conditions such as AIDS or cancer of the lymph, bone or blood. The vaccine should not be administered to women who are or may be pregnant.