Herpes Zoster. The shingles vax rolls out from today. Despite an efficacy dilemma, funding the shingles vaccine should be a boon to the elderly.
POST-HERPETIC neuralgia (PHN) brings pain and misery — it’s the nasty, hard-to-treat sequel to shingles that elderly people are desperate to avoid.
Secondary infection, scarring, ophthalmic and hearing disorders, neurological symptoms and, above all, months of pain, are among the complications of shingles. There’s also a 60% increased risk of stroke in the first few weeks.
Although the disease is mostly self-limiting, the proportion of patients who will develop PHN increases with age from about one in ten cases for people in their 50s to one in four cases among those in their 80s.1
The dilemma for public health policymakers is that while the risk of developing PHN increases with age, the likelihood of a robust immune response to the available vaccine, Zostavax (Seqirus/Merck, Sharp & Dohme) declines.
The Key Points
- Zostavax is free under the NIP for 70 year olds
- People aged 71 to 79 can receive it in a catch-up program
- Efficacy in this age group is 41%
- Zostavax is contraindicated in the immunocompromised
- A single dose of vaccine should be administered subcutaneously in the deltoid region
- Reconstituted Zostavax should be discarded if not used within 30 minutes
- Zostavax can be co-administered with an inactivated vaccine at a separate injection site
- It’s not necessary to check VZV serology before vaccination
- Zoster vaccination is not recommended in people previously vaccinated with varicella vaccine
- People who’ve had shingles can be vaccinated after a wait of at least a year
Sources: Department of Health, NCIRS, Seqirus.
Infectious diseases specialist Associate Professor Kristine Macartney, deputy director of the National Centre for Immunisation Research and Surveillance (NCIRS), Sydney, notes that in the pivotal Zostavax clinical trial, vaccine effectiveness was a non-significant 18% in those older than 80.2
To get the most bang for the taxpayer buck, a government-funded program needs to target a segment of the population which not only has an elevated risk of developing the disease, but also has a good chance of responding well to the vaccine.
Zostavax, the first newly funded adult vaccine in more than a decade, will be offered under the National Immunisation Program (NIP) for 70 year olds from today, November 1, with a catch-up program for those aged 71 to 79 running until October 2021.