Recent epidemiological studies have suggested that vaccination against HZ may be associated with a lower risk of dementia. The scoping review captures related aspects such as the association between HZ infection and dementia, as well as broader links between vaccinations in general and dementia incidence.

In 2024, following a request from the Department of Health, HIQA published a health technology assessment (HTA) of the addition of HZ vaccination to the adult vaccination programme. While the HTA found clear and consistent evidence that the recombinant zoster vaccine (RZV) is safe and effective at reducing HZ cases, it noted that effectiveness diminishes over time. At the submitted price, HZ vaccination was found not to represent an efficient use of healthcare resources in Ireland. The economic evaluation took into account the benefits arising from reductions in the incidence of HZ and PHN.

Herpes zoster (HZ), commonly known as shingles, is characterised by a painful, blistering rash that typically takes two to four weeks to resolve. HZ occurs due to reactivation of latent varicella zoster virus, usually decades after primary varicella (chicken pox) infection. Among those with a history of varicella, the individual life-time risk of developing HZ is approximately 30%. The most frequent complication of HZ is post-herpetic neuralgia (PHN), referring to persistent chronic pain after the resolution of the acute rash.