People who are aged 50 years and older or who are immunocompromised are at increased risk of herpes zoster and are recommended to receive zoster vaccine. The live attenuated zoster vaccine recommended for immunocompetent adults is contraindicated in severely immunocompromised populations, who are instead recommended to receive the recombinant zoster vaccine (RZV). The indication for RZV in Australia has been recently extended to immunocompromised patients aged 18 years and older, and RZV is now recommended as the safer and more efficacious vaccine in at-risk populations.
Herpes zoster (HZ) is caused by reactivation of the varicella zoster virus (VZV) from the dorsal root or trigeminal nerve ganglia, resulting in a characteristic papulovesicular dermatomal rash and moderate to severe neuritic pain. This pain may persist as postherpetic neuralgia (PHN), defined as pain beyond 90 days after onset of the rash. Reactivation is controlled by specific immunity, especially T-cell mediated immunity, which declines with age in the phenomenon of ‘immunosenescence’.