Herpes Zoster

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Herpes Zoster

Commonly called shingles Reactivation of latent varicella zoster virus

– Latent virus in dorsal ganglia following primary infection Incidence and severity increase with age Develops in approximately 30% of individuals

over a lifetime Annual incidence 1.5 to 4 cases per 1000

individuals – 1 million or more cases in U.S.

Herpes Zoster Complications

Postherpetic neuralgia—persistent pain after skin lesions healed

May limit daily activities and decrease quality of life

MMWR 2008

Zoster Vaccine

Licensed for adults > 50 years Recommended for all adults > 60 years

– ACIP made no decision regarding 50-59 year olds Supply, durability of immunity, cost effectiveness

Contains live attenuated Oka/Merck varicella vaccine virus

– High dose of virus– Not interchangeable with varicella vaccine to prevent

chickenpox

Zoster Vaccine

Do not use in immunocompromised– Malignancy, solid organ transplant, HIV/AIDS, high

dose steroids– OK to use in patients taking low dose or topical

steroids, low dose methotrexate, azathioprine, or 6-mercaptopurine

No interval needed for immune globulin or blood products

Avoid in pregnant women or women who might become pregnant in next month

Administration with Other Vaccines

Inactivated influenza vaccine ok Lower zoster vaccine antibody with

administered concurrently with PPSV23– Clinical significance??

Package insert states to avoid No antibody correlate of protection T cell immunity most important for protection from zoster No decrease in zoster vaccine effectiveness observed ACIP addresses the issue with its rule regarding acceptable

coadministration of inactivated and live vaccines

Zoster Vaccine Efficacy

19,000 individuals followed for median of 3 years

Burden of disease main outcome– Composite measure of incidence, severity,

duration of herpes zoster– Decreased by 61% in vaccine group

Reduced incidence of herpes zoster by 51%; reduced incidence of postherpetic neuralgia by 67%

Zoster Vaccine Efficacy in 50-59 years of age

Vaccine efficacy 70% (CI 54-81%) Injection site reactions reported (64%

vs. 14% for placebo) Systemic adverse reactions (35.4%

vaccine vs. 33.5% placebo)

Screening

Health status Allergies Current illnesses or chronic conditions Current medications For females, pregnancy Recent immunization History of varicella infection not needed Recent blood products not an issue

Adverse Events

Vaccine rash more frequently in vaccine recipients than in those receiving placebo

– 0.1% vs 0.04%; p<0.05

Theoretical risk of vaccine virus transmission Vaccine virus has not been isolated from skin

lesions in those who developed rash post-immunization

– Wild type virus was detected in some specimens

Injection Site Reaction

Zoster Vaccine

Zoster Vaccine Questions

Use of zoster vaccine in immunocompromised– Recommended for those anticipating immunosuppressive therapy and

early HIV if >50 years

Benefit in those with history of shingles Transmission of vaccine virus—theoretical

concern Duration of protection about 10 years

– No recommendation for additional doses

GSK Investigational Vaccine

gE with adjuvant Reduced risk of shingles by 97% in

phase III trial– Individuals >50 years– Two dose series at 0 and 2 months

Unknown timeline for FDA review