From the 1st November 2016, Zostavax® is available on the National Immunisation Program (NIP) for people aged 70 years. A five-year catch-up program has also been introduced for people aged 71-79 years.
Zostavax® is indicated for the prevention of herpes zoster (shingles) in people aged 50 years and older. It contains the same live, attenuated varicella-zoster virus (VZV) strain as the varicella (chickenpox) vaccine. However, Zostavax® is approximately 14 times as potent. A greater potency is required as, although people usually remain seropositive to VZV after primary infection, cellular immunity tends to wane with age.
Herpes zoster is a significant cause of morbidity in the elderly and affects 50% of people who live to 85 years of age. Complications such as post-herpetic neuralgia are also more common in older populations and may be prolonged and disabling. The Shingles Prevention Study investigated the efficacy of Zostavax® in people aged 60 years and older. This large, double-blind trial demonstrates a 51.3% reduction in the incidence of herpes zoster and a 66.5% reduction in post-herpetic neuralgia compared to placebo. Although superior efficacy is seen in younger patients, the duration of vaccine protection is currently undetermined. Clinical benefit is, therefore, anticipated to be greatest when administered to older people due to their higher risk of developing herpes zoster and its complications.
History of primary VZV infection is not required before routine administration of Zostavax®. The use of high-dose VZV vaccines is considered safe and effective in these patients, although minor injection-site reactions may be more frequent. Alternatively, if serological testing is negative, two doses of low-dose VZV vaccine should be administered. Zostavax® is contraindicated in people who are severely immunocompromised.
- Department of Health. Zoster (herpes zoster). In: The Australian Immunisation Handbook. 10th ed. Canberra: Australian Government, 2016.
- Oxman MN, Levin MJ, Johnson GR, Schmader KE, Straus SE, Gelb LD, et al. A vaccine to prevent herpes zoster and postherpetic neuralgia in older adults. N Engl J Med. 2005; 352(22): 2271-84.
- Zostavax® (zoster virus vaccine live) Australian approved product information. Macquarie Park: Merck Sharp & Dohme. Approved April 2016.