Missed Zoster Vaccination Booster: What to Do
If you miss the second dose of Shingrix (recombinant zoster vaccine), simply administer it as soon as possible—there is no need to restart the series, and effectiveness is not impaired even if given beyond the recommended 2-6 month window. 1, 2
Key Management Principles
No Need to Restart the Series
- The second dose should be given as soon as feasible after the missed appointment, regardless of how much time has elapsed since the first dose. 1
- Real-world data demonstrates that second doses administered at ≥180 days (beyond 6 months) maintain full effectiveness with no significant reduction in protection. 2
- There is no maximum interval after the first dose—waiting serves no purpose while leaving the patient vulnerable to herpes zoster. 1
Optimal Timing Considerations
- The recommended interval between doses is 2-6 months, with a minimum interval of 4 weeks. 3, 1
- If the second dose was inadvertently administered earlier than 4 weeks, that dose should be repeated. 3
- For immunocompromised adults aged ≥18 years, a shorter schedule with the second dose given 1-2 months after the first dose is acceptable. 1
Real-World Completion Data
Series Completion Rates
- Among patients who received the first dose, approximately 70% completed the two-dose series within 6 months and 80% within 12 months. 4, 5
- Among those who received only one dose with at least 12 months of follow-up, 96% had a missed opportunity for second-dose vaccination during a healthcare visit. 5
- Notably, 36% of patients with incomplete series had a visit for influenza or pneumococcal vaccination within 2-12 months of their first RZV dose, representing clear missed opportunities. 5
Effectiveness of Delayed Second Dose
Clinical Evidence
- Two-dose vaccine effectiveness remains robust even when the second dose is delayed beyond the recommended 6-month window. 2
- Real-world effectiveness of the complete 2-dose series is 70.1% (95% CI, 68.6-71.5) for preventing herpes zoster. 2
- Single-dose effectiveness is only 56.9% (95% CI, 55.0-58.8), emphasizing the critical importance of completing the series. 2
- Two-dose effectiveness against postherpetic neuralgia is 76.0% (95% CI, 68.4-81.8). 2
Common Pitfalls to Avoid
Do Not Restart the Series
- Never restart the vaccination series from the beginning—this wastes vaccine and delays full protection. 1
- The first dose remains valid indefinitely, and the second dose should simply be administered when the patient returns. 1
Do Not Use Zostavax as a Substitute
- Only Shingrix (RZV) should be used for completing the series—do not substitute with the older live-attenuated Zostavax vaccine. 1
- Shingrix offers superior efficacy (>90% in clinical trials) compared to Zostavax, which demonstrates poor long-term protection with efficacy declining to only 14.1% by year 10. 1
Capture Missed Opportunities
- Schedule the second dose at the time of any healthcare visit, including visits for other vaccinations like influenza or pneumococcal vaccines. 5
- Pharmacy-based vaccination has helped increase series completion rates and should be utilized when convenient for the patient. 5
Special Population Considerations
Immunocompromised Patients
- For immunocompromised adults, the second dose can be given 1-2 months after the first dose, which is a shorter interval than for immunocompetent adults. 1
- Shingrix maintains effectiveness in immunocompromised individuals, unlike the live-attenuated Zostavax which is contraindicated in this population. 1