Two-dose injection prevents most shingles and lasting nerve pain for more than a decade. Ordinary-practice protection is lower but substantial, including when immunity is suppressed. Injection-site pain, fever, aches, and fatigue are common. Rare risk of weakness from an immune attack on nerves was seen in older adults. Dementia, heart attack, and stroke from medical records are not trial proof. (Full Review)
| Marker | Target | Why |
|---|---|---|
| gE-specific IgG or VZV IgG | No established functional target; track series completion instead | Research immunogenicity only |
| Clinical shingles episode | None after the two-dose series | Detects breakthrough |
| New neurologic weakness | Absent, especially days 1–42 after a dose | Screen for GBS |
Cadence: Dose 2 at 2–6 months (1–2 months if immunocompromised); 1–3-day reactogenicity window and 42-day neurologic window after each dose; then only if vesicular dermatomal rash or unexplained weakness appears