Zostavax can give older people protection against herpes zoster for five to 10 years, but it is not 100% efficacious.
The zoster vaccine is funded under the National Immunisation Program for persons aged 70 years, with catch-up for those aged 71–79 years, also funded until October 2021.
The vaccine efficacy is around 64% in the 60 to 69 age group, and around 38% for people aged between 70 and 79.
In people aged over 80, the efficacy drops to 18% and actually is not statistically significant, says Associate Professor Kristine Macartney, a paediatrician specialising in infectious diseases based at the University of Sydney.
“[Zostavax] is not going to prevent zoster in all of your patients,” she says. “But it is going to give them a significantly good chance of reducing the likelihood of them getting zoster. So, this is still worthwhile and turns out to be cost-effective.”