Dementia Delayed by Herpes Zoster Vaccination

Recent research suggests that a herpes zoster (HZ) vaccine, commonly referred to as the shingles vaccine, may reduce the risk of receiving a dementia diagnosis following vaccination.

According to a study published in JAMA on April 23, 2025, there is evidence of a beneficial effect of herpes zoster vaccination in preventing or delaying dementia, which is more likely to be causal than the associations reported in existing correlational evidence.

In this quasi-experimental study using electronic health record data from Australia, being eligible for herpes zoster vaccination based solely on date of birth significantly decreased the probability of receiving a new dementia diagnosis during 7.4 years by 1.8 percentage points.

A similar study conducted in Wales also showed that HZ vaccination appears to prevent or delay the onset of dementia by about 20%.

These researchers wrote, 'this study and the analysis in Wales provide evidence that is more robust to confounding concerns (eg, healthy vaccinee bias) than is the existing associational evidence.'

In the United States, shingles vaccination services are offered at most pharmacies in April 2025.