How do vaccines protect against shingles later in life?

After chickenpox, the varicella-zoster virus can remain dormant in nerve tissue for years or decades. If immunity weakens, the virus can reactivate as shingles, causing a painful rash and sometimes long-lasting nerve pain called postherpetic neuralgia. Shingles vaccines boost immune control of the virus, especially in older adults whose immunity has declined with age. The newer recombinant shingles vaccine has been shown to be highly effective in preventing shingles and its complications. Vaccination is especially recommended for older adults and some younger adults with higher risk.