Herpes Zoster: Who's at Risk and Who Should be Vaccinated

Craig M. Hales, MD, MPH


November 21, 2011


Hello. I'm Dr. Craig Hales. I'm a physician and epidemiologist at the Centers for Disease Control and Prevention (CDC). I'm speaking with you as part of the CDC Expert Commentary Series on Medscape. Today, we will talk about herpes zoster vaccine—the effectiveness of this vaccine and the current recommendations for vaccinating patients.

First, let's start with some basics about herpes zoster and who is at risk. Herpes zoster, which is commonly known as shingles, is a painful skin rash. This disease is caused by the varicella zoster virus—the same virus that causes chicken pox. After a person recovers from chicken pox, the virus stays dormant in the sensory ganglia and can reactivate years later and cause herpes zoster.

Each year, about 1 million people develop zoster in the United States. A person's lifetime risk is 30%. Typically, most people have only one occurrence in their lifetime; however, second and even third occurrences are possible.

Anyone who has had varicella can develop zoster, even children. However, it's most common in adults. About half of all cases occur in men and women 60 years of age and older. Zoster is more common in people who are immunocompromised and in people who are taking medications that suppress their immune systems. For example:

  • People with cancer, especially leukemia and lymphoma, or HIV;

  • People with bone marrow or solid organ transplants; or

  • People taking steroids, chemotherapy, or transplant-related medications.

Adults with zoster are at high risk for post-herpetic neuralgia (PHN); this is the most common complication. PHN causes persistent pain in the area where the rash once was. The incidence, duration, and severity of PHN increases with age. People under 40 years old rarely get PHN; it occurs most commonly in people 60 years of age and older.

Zoster is preventable with vaccination. In a clinical trial involving 38,000 adults 60 years of age or older, the vaccine reduced the risk for zoster by 51% and the risk for PHN by 67%. An observational study in a large health maintenance organization showed similar results of vaccine effectiveness.

Healthcare providers can protect their patients by making sure they get vaccinated. The Advisory Committee on Immunization Practices (ACIP) recommends that adults 60 years of age and older get vaccinated against zoster. Adults should receive 1 dose.

Zoster vaccine can be given to patients even if they have already had zoster, in order to prevent recurrence. Serologic testing for immunity to varicella is not needed. Patients can receive other vaccines, such as influenza and pneumococcal vaccines during the same visit.

It is safe for patients who were just vaccinated to be around infants, young children, pregnant women, or people with compromised immune systems. There have not been any reports of varicella cases from exposure to persons who recently received zoster vaccine.

Since the zoster vaccine contains a live, attenuated virus, it should not be given to people with compromised immune systems. Also, pregnant women or people who have had an anaphylactic reaction to any vaccine component should not get the vaccine.

In March 2011, the Food and Drug Administration expanded the licensure of zoster vaccine to include adults 50-59 years old. This decision was based on results of a clinical trial that followed 22,000 participants for an average of 1.3 years. In this study, the vaccine reduced the risk for zoster by about 70% in adults 50-59 years old.

After considering these results and other factors, including vaccine shortages and disease burden across various age groups, ACIP decided in June 2011 to maintain the current recommendation for vaccinating adults 60 years of age and older against zoster. However, healthcare providers can still offer the vaccine to patients 50-59 years old.

Understanding the recommendations for zoster vaccine will help healthcare providers address questions from their patients. Healthcare providers can prevent zoster and its complications by understanding the risks and ensuring that patients get vaccinated.

Thank you.

Web resources

CDC Shingles

CDC Vaccines and Immunizations

Craig Hales, MD, MPH, is a preventive medicine physician and epidemiologist in the National Center for Immunization and Respiratory Diseases, Division of Viral Diseases, at the Centers for Disease Control and Prevention in Atlanta, Georgia. Dr. Hales received his MD from Northwestern University and his MPH from the Johns Hopkins University. His current work focuses on surveillance and epidemiology of herpes zoster (shingles) as well as zoster vaccine uptake, effectiveness, and vaccine policy.