Shingles

Health Professionals Overview

The annual incidence of shingles is estimated to be around one million cases and the lifetime prevalence is about 25 percent.[Oxman, FDA CBER] Since virtually all adults in the United States have had chickenpox, every adult is at risk of developing shingles. Moreover, as the population ages, incidence and prevalence can be expected to rise. However, while shingles most often strikes 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.[Lydick] While antiviral therapy may reduce the severity and duration of the initial attack, it does not prevent development of post-herpetic neuralgia (PHN),[Gnann, Kost] the key consequence of shingles that can persist for years and is often resistant to treatment.[Dworkin] Given the substantial morbidity associated with shingles and PHN, and the lack of effective treatments for the latter, prevention is a justifiable goal.

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

A vaccine for the prevention of reactivation of varicella-zoster virus (VZV) was approved for use in persons 60 years and older in 2006.[FDA Approval] 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 VZV.[Oxman]

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.[CDC] However, it is the appearance of the rash, usually unilaterally on the trunk or face and limited to a single dermatome, that simplifies shingles diagnosis.[CDC, Gnann] 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.[Arvin]

The rash usually begins as a cluster of papules that develop into vesicles and then into pustules.[CDC, Gnann] 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.[CDC, Dworkin, de Moragas] 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.[FDA encore]

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.[Wood, Decroix] The presence of new vesicles indicates ongoing viral replication and potential for positive effect of antiviral therapy.

During the acute phase of the disease, over-the-counter analgesics may be sufficient. More severe pain may require addition of prescription medication, 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.

References

Arvin A. Aging, immunity, and the varicella-zoster virus. N Engl J Med 2005;352:2266-2267.

Centers for Disease Control and Prevention. Epidemiology and Prevention of Vaccine-Preventable Diseases. Atkinson W, Hamborsky J, McIntyre L, Wolfe S, eds. 9th ed. Washington DC: Public Health Foundation, 2006.

Decroix J, Partsch H, Gonzalez R, et al. Factors influencing pain outcome in herpes zoster: an observational study with valaciclovir. J Eur Acad Dermatol Venereol 2000;14:23-33.

de Moragas JM, Kierland RR. The outcome of patients with herpes zoster. AMA Arch Derm 1957;75:193-196.

Dworkin RH, Schmader KE. The treatment and prevention of postherpetic neuralgia. Clin Infect Dis 2003;36:877-882.

Gnann JW Jr, Whitley RJ. Herpes zoster. N Engl J Med 2002;347:340-360.

Kost RG, Straus SE. Postherpetic neuralgia-pathogenesis, treatment, and prevention. N Engl J Med 1996;335:32-42.

Lydick E, Epstein RS, Himmelberger D, White CJ. Herpes zoster and quality of life; a self-limited disease with severe impact. Neurology 1995;45(Suppl 8):S52-S53.

Oxman MN, Levin MJ, Johnson GR, et al for the Shingles Prevention Study Group. A vaccine to prevent herpes zoster and postherpetic neuralgia in older adults. N Engl J Med 2005;352:2271-2284.

U.S. Food and Drug Administration. FDA licenses new vaccine to reduce older Americans' risk of shingles. Available at: http://www.fda.gov/bbs/topics/news/2006/new01378.html as of September 17, 2006.

U.S. Food and Drug Administration. Shingles: an unwelcome encore. Available at: http://www.fda.gov/fdac/features/2001/301_pox.html as of September 17, 2006.

U.S. Food and Drug Administration. Production approval information--licensing action. Zostavax™ questions and answers. Available at http://www.fda.gov/cber/products/zosmer052506qa.htm as of September 17, 2006.

Wood MJ, Shukla S, Fiddian AP, Crooks RJ. Treatment of acute herpes zoster: effect of early (<48 h) versus late (48-72 h) therapy with acyclovir and valacyclovir on prolonged pain. J Infect Dis 1998;178(Suppl 1):S81-S84.