What You Need to Know About Herpes Zoster Vaccination: Recommendations From the CDC

The CDC's Advisory Committee on Immunization Practices (ACIP) recommends that all persons older than 60 years be immunized against herpes zoster with a single dose of the live, attenuated virus vaccine. Furthermore, it urges clinicians to offer the vaccine at the first available clinical encounter.

The recommendations, which appear in Morbidity and Mortality Weekly Report (MMWR), can be accessed online at www.cdc.gov/mmwr/preview/mmwrhtml/rr57e0515a1.htm?s_cid=rr57e0515_e.¹ These recommendations are the first statement made by the ACIP advocating the use of a live, attenuated virus vaccine for the prevention of herpes zoster. The hope-promised by results of several clinical trials cited in the MMWR article-is that routine immunization of older adults will significantly reduce the incidence of and morbidity associated with herpes zoster.

Each year, about 1 million cases are diagnosed in the United States. Post-herpetic neuralgia (PHN) develops in many of the affected patients; other complications include ocular sequelae (eg, herpes zoster ophthalmicus [Figure 1]), varicella-zoster virus viremia, and serious neurological conditions and viral dissemination to viscera, especially in immunocompromised persons. Older adults (beginning at about age 50) are at particular risk for herpes zoster (Figure 2) and subsequent PHN; these conditions develop in about 50% of persons who live to age 85 years.^2,3

THE VACCINE AND VACCINATION

Each 0.65-mL dose of the zoster vaccine (when reconstituted and stored at room temperature for up to 30 minutes) contains a minimum of 19,400 plaque-forming units of the Oka/Merck strain of varicella-zoster virus. This vaccine is appreciably more potent than the varicella vaccine routinely used in children to prevent chickenpox. It is administered subcutaneously to the deltoid area. A single dose is all that is required (booster doses are not licensed for use).

Zoster vaccine should be stored in a freezer that maintains an average temperature of 215°C (5°F) or colder. Once reconstituted, the vaccine should be used immediately (within 30 minutes). After this time, the potency degrades. If unused, the reconstituted vaccine should be discarded.

The zoster vaccine is licensed for use only in persons 60 years and older. It is safe for those who are receiving blood products. Persons who already have been vaccinated against varicella-zoster virus should not be re-immunized; however, the ACIP stated that concern regarding unintentional re-immunization in persons 40 years and older was slight because varicella vaccination did not begin in the United States until 1995. The ACIP also noted that there is no need to question older patients about a history of chickenpox or to conduct serological testing for varicella immunity before administering the vaccine. Persons who have had an episode of herpes zoster in the past can receive the vaccine, but it should not be used to treat acute herpes zoster or PHN or be used as prophylaxis against PHN. In the absence of contraindications and precautions related to health status, persons with chronic renal failure, diabetes mellitus, rheumatoid arthritis, chronic pulmonary disease, or other chronic conditions can receive the vaccine.

VACCINE COADMINISTRATION

Although the zoster vaccine can be administered along with the trivalent inactivated influenza vaccine without compromising the effectiveness of either one, no data are available on the effects of administrating the zoster vaccine with other vaccines that are routinely recommended for persons 60 years and older. Because simultaneous administration of most commonly used live, attenuated, and inactivated vaccines-in general-has yet to be associated with impaired immune response and has not been associated with an increased rate of adverse events,⁴ the zoster vaccine can be administered in the setting of other indicated (inactivated) vaccines during the same office visit. The ACIP reminds clinicians that when multiple vaccines are to be given during a single office visit, they should be administered to different anatomic sites using separate syringes. Although the zoster vaccine can be administered at any time along with an inactivated virus vaccine, it should be administered at least 4 weeks before or after administration of another live, attenuated virus vaccine.

WHO SHOULD NOT BE VACCINATED

Because the risk of morbidity and mortality from herpes zoster is heightened in immunocompromised persons, eligible patients who are scheduled to begin immunosuppressive therapy should be immunized at least 14 days (preferably a month, according to some experts⁵) before such therapy is initiated. Otherwise, immunization is contraindicated in immunocompromised persons. Exceptions and caveats to these guidelines are listed in the Table.

Although a history of neomycin-associated contact dermatitis is not a contraindication to receiving the zoster vaccine, persons who have a history of anaphylactic reaction to any component of the vaccine, including neomycin, should not receive it.⁴ Pregnant women-who are not in the target age group for herpes zoster immunization anyway-should not receive the vaccine. The CDC and the vaccine's manufacturer have established a registry to monitor maternal-fetal outcomes of pregnant women who inadvertently have been given live, attenuated varicella-zoster virus–type vaccines within a month of becoming pregnant. The telephone number of the registry is 800-986-8999.

Persons who are receiving antiviral medications such as acyclovir, famciclovir, and valacyclovir should not be vaccinated in the setting of active therapy. Rather, therapy should be discontinued for at least 24 hours before the zoster vaccine is administered, and at least 14 days should elapse postvaccination before resuming antiviral therapy.⁴ Because these antiviral agents are active against herpesviruses, they could interfere with vaccine efficacy.

References:

REFERENCES:
1. Harpaz R, Ortega-Sanchez IR, Seward JF; Centers for Disease Control and Prevention. Prevention of herpes zoster. Recommendations of the Advisory Committee on Immunization Practices (ACIP). Published May 15, 2008. http://www.cdc.gov/mmwr/preview/mmwrhtml/rr57e0515a1.htm?s_cid=rr57e0515_e. Accessed June 5, 2008.
2. Brisson M, Edmunds WJ, Law B, et al. Epidemiology of varicella zoster virus infection in Canada and the United Kingdom. Epidemiol Infect. 2001;127:305-314.
3. Schmader K. Herpes zoster in older adults. Clin Infect Dis. 2001;32:1481-1486.
4. Kroger AT, Atkinson WL, Marcuse EK, Pickering LK; Advisory Committee on Immunization Practices (ACIP) Centers for Disease Control and Prevention (CDC). General recommendations on immunization: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR. 2006;55(RR-15):1-48.
5. Ihara T, Kamiya H, Torigoe S, et al. Viremic phase in a leukemic child after live varicella vaccination. Pediatrics. 1992;89:147-149.