Should People with HIV Avoid the Shingles Vaccine?

Weighing the Risk in Immune Compromised People

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On May 26, 2006, the U.S. Food and Drug Administration (FDA) approved the vaccine Zostavax to prevent herpes zoster, a viral disease commonly known as shingles. While it was initially approved for adults 60 and older, it specifically excluded those with HIV.

Those recommendations were later revised in 2011 to include adults 50 and older while making no specific recommendations regarding its use in those with HIV.

Zostavax is a live attenuated vaccine, meaning that it made with a live, weakened virus. It is a larger dose of the chickenpox vaccine at almost 14 times the potency. Research has shown that Zostavax can reduce the risk of shingles by 51 percent while reducing the severity and duration of an outbreak by 67 percent.

Causes of Shingles

Shingles is characterized by a painful rash with blisters that appear in a band or stripe on one side the face or body. It is caused by the reactivation of varicella zoster virus (VZV) in adults who previously had chickenpox.

While the virus generally lies dormant on nerve cells near the spine, it can cause an eruption when reactivated. The eruption is constrained to a specific nerve root, known as a dermatome, which branches off either to the left or right side of the body.

It is estimated that one in three people globally will develop shingles over the course of a lifetime.

In the U.S., more than a million cases are reported annually. The risk of shingles is also known to increase as a person ages, more than doubling by the age of 65.

Shingles in People with HIV

VZV reactivation can occur when a person's immune defenses are low. This can occur as a person ages but also when HIV infection depletes the immune cells called CD4 T-cells.

The greater the loss of T-cells, the greater the shingles risk (particularly as the CD4 count drops below 350). High viral loads are also associated with an increased shingles risk.

While HIV therapy has slashed the incidence of shingles in people living with HIV by nearly a third, the risk remains equal to that of adults over 65. All told, the risk of shingles with HIV is as much as 10 times greater than that of the general population.

Moreover, HIV infection is associated with the greater likelihood of shingles complications, including disseminated shingles (affecting three or more dermatomes), shingles of the eyes or internal organs, or shingles recurrence within six months.

Research from John Hopkins University suggested that as many as 28 percent of HIV-positive people with shingles may experience such complications.

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" should avoid it). there is growing evidence in support of its use.

In 2012, scientists with the longstanding AIDS Clinical Trials Group concluded that Zostavax was safe and effective in people with CD4 counts as low as 200.

While the results were encouraging, many remained concerned about the overall of the vaccine in people with CD4 counts under 200. As a live vaccine, there remains a possibility that even a weakened virus can cause the very illness it was meant to prevent.

While the Centers for Disease Control and Prevention does not currently recommend Zostavax in people with HIV, the clinical opinion appears to be shifting. Most infectious disease specialists support the use of Zostavax in HIV-positive adults 50 and older who have sustained undetectable viral load and a CD4 count over 200. In the same vein, most agree that Zostavax should never be used in people with CD4 counts under 200.

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

Sources:

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

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. DOI: 10.1097/QAI.0b013e318266cd3c.

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.