Should People with HIV Get the Shingles Vaccine?

Current Evidence and Considerations

Shingles.jpg used under a Creative Commons license at http://commons.wikimedia.org/wiki/File:Herpes_zoster_chest.png
Herpes zoster (shingles). Photograph © Fisle, 2007

On May 26, 2006, the U.S. Food and Drug Administration (FDA) approved the use of the vaccine Zostavax to prevent herpes zoster, a viral disease commonly known as shingles. While initially only approved for adults 60 years of age and older—excluding individuals with HIV/AIDS—the FDA revised their recommendations on March 21, 2011 to expand its use to adults 50 years of age and older, while making no specific recommendations regarding its application in people infected with HIV.

What Is Zostavax?

Zostavax is classified as a live attenuated vaccine, meaning that it employs a live virus that has been less harmless, as opposed to inactivated vaccine, which employs killed virus. (The measles and mumps vaccines are other examples of live attenuated vaccines.)

Zostavax is actually a larger dose of the chicken pox vaccine already in wide use around the world since both shingles and chicken pox share the same causative virus, the varicella zoster virus (or VZV). Zostavax's minimum potency is, in fact, 14 times that of the chicken pox vaccine.

Research have shown that Zostavax can reduce the incidence of shingles by approximately 51%, while reducing both the severity and duration of pain in those affected by some 67%.

What Is Shingles?

Shingles is characterized by a painful skin rash with blisters that appear along a band or stripe (or in a specific area) on one side the face or body.

Shingles is caused by the reactivation of VZV in adults who have previously had chicken pox, or approximately 99.5% of American over the age of 40, according the U.S. Centers for Disease Control and Prevention (CDC). While the virus generally lie dormant on nerve cells near the spine, when reactivated it causes an eruption along a specific dermatome of the body (i.e., the area of skin that is supplied with a single branch of nerve cells).

This accounts for the localized distribution of shingles rashes.

Globally, it is estimated that one out of three individuals will develop shingles over the course of a lifetime. In the U.S. alone, more than a million cases are reported annually. The risk of shingles is also known to increase as a person ages, more than doubling in risk—from an annual rate of four cases per 1,000 to over 10 cases per 1,000—in those 65 years of age and older.

Shingles in People with HIV

VZV reactivation can occur when cellular immunity—characterized by the robustness of an individual's T-cell response—is depleted, as happens when a person ages. The same occurs in people with HIV insofar as disease progression is associated with the gradual depletion of CD4+ T-cells. The greater the depletion of T-cells, the greater the risk, particularly as the CD4 count drops below 350 cells/mL. High viral loads are also seen to be associated with increased shingles risk.

While combination antiretroviral therapy (cART) has slashed the incidence of shingles among people living with HIV by nearly a third, the risk is equal to that of adults over the age 65 and is most likely to occur between the ages of 30 and 45.

Overall, the risk of shingles among people with HIV is between five to 10 times greater than that of the general population.

Furthermore, HIV infection is associated with the greater likelihood of shingles complications, either in the form of disseminated shingles (affecting three or more dermatomes); shingles of the eyes or internal organs; neurological complications; or recurrence within six months. Research from John Hopkins University in 2012 suggested that up to 28% of HIV-infected patients with shingles may experience such complications.

The same study concluded that, in individuals with low CD4 counts (below 200 cells/mL) and high viral loads, shingles were more likely to occur within 90 days of cART initiation—mostly likely due to the inflammation that can occur with sudden immune reactivation (known as IRIS, or immune reconstitution inflammatory syndrome).  

Zostavax Recommendations for People with HIV

While the FDA has made no formal recommendations regarding the use of Zostavax in people with HIV—other than to state that individuals with "weakened immune systems" avoid it—there is growing evidence in support of its use.

Investigators with the federally funded AIDS Clinical Trials Group (ACTG) conducted research in 2012 to determine the efficacy of Zostavax in 192 patients with CD4 counts between 200 and 349 cells/mL and 203 patients with CD4 counts of 350 cell/mL or higher. The study determined that the vaccine was safe and well-tolerated in both groups, with a sustained antibody levels suggesting an effective immune response.

While the results are encouraging, there are still concerns as to overall safety of the vaccine, most specifically in patients with low CD4 counts. For its part, the CDC currently does not recommend Zostavax in the presence of HIV, although clinical opinion appears to be shifting. The growing option tends to support it use in patients 50 years of age and older who have sustained viral control and CD4 counts above 200 cells/mL.

In the same vein, most agree that Zostavax should never be used in patients with CD4 counts under 200 cells/mL.

Zostavax should also be avoided in patients with no history of chicken pox or evidence of VZV antibodies. For these individuals, only primary chicken pox vaccination (such as Varivax or Varilrix) may be considered.

Before considering Zostavax use, always consult with your primary care provider and/or an HIV specialist. In the event that shingles occurs after a vaccination, seek immediate medical attention. The antiviral Zovirax (acyclovir) is sometimes prescribed to help prevent severe disease expression.

Sources:

U.S. Food and Drug Administration (FDA). "FDA Licenses New Vaccine to Reduce Older Americans’ Risk of Shingles." Silver Springs, Maryland; press release issued May 26, 2006.

U.S. Food and Drug Administration (FDA). "FDA Approves Zostavax vaccine to prevent shingles in individuals 50 to 59 years of age." Silver Springs, Maryland; press release issued May 24, 2011.

U.S. Centers for Disease Control and Prevention (CDC). "Herpes Zoster Vaccination: Information for Health Care Professionals." Atlanta, Georgia; June 6, 2013; accessed June 24, 2014.

U.S. Centers for Disease Control and Prevention (CDC). "Shingles Vaccination: What You Need to Know." Atlanta, Georgia; November 8, 2013; accessed June 24, 2014.

U.S. Centers for Disease Control and Prevention (CDC). "Shingles (Herpes Zoster): Clinical Overview." Atlanta, Georgia; May 1, 2014; accessed June 24, 2014.

Blanks, L.; Polydefkis, M.; Moore, R.; et al. "Herpes zoster among persons living with HIV in the current antiretroviral therapy era." Journal of Acquired Immune Deficiency Syndromes. October 1, 2012; 61(2):203-207.

Benson, C.; Hua, L.; Andersen, J.; et al. "ZOSTAVAX is generally safe and immunogenic in HIV+ adults virologically suppressed on ART: results of a phase 2, randomized, double-blind, placebo-controlled trial." 19th Conference on Retroviruses and Opportunistic Infections (CROI); Seattle, Washington; March 5-8, 2012; abstract 96.

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