Last April I wrote a Ground Truths entitled “The Shingles Vaccine and Reduction of Dementia.” At the time many were unaware of this unanticipated relationship based on 2 large natural experiments. Two new studies this week have advanced our understanding about the potential biological impact of the Shingles vaccine, independent of its effects for preventing Shingles or direct action vs. herpes zoster virus and reinforced its protection from dementia, ~80% of which is attributable to Alzheimer’s ...