Recommendation for Patient with No Titer After Two Shingles Vaccines
Do not administer additional Shingrix doses based solely on absent antibody titers, as serologic testing is not recommended or validated for assessing vaccine response to recombinant zoster vaccine. 1, 2
Why Serologic Testing Is Not Indicated
Antibody titers do not correlate with protection for Shingrix. Unlike hepatitis B or varicella vaccines where antibody levels predict immunity, the protective mechanism of recombinant zoster vaccine (RZV/Shingrix) relies primarily on cell-mediated immunity (VZV-specific CD4+ T-cell responses), not humoral antibody responses 3, 4
No validated serologic correlate of protection exists for Shingrix. The FDA approval and clinical efficacy data (97.2% efficacy in adults ≥50 years) were based on clinical endpoints (prevention of herpes zoster), not antibody titers 2, 3
Guidelines explicitly do not recommend checking titers after zoster vaccination. This contrasts sharply with hepatitis B vaccination, where post-vaccination serologic testing is standard practice for certain populations 5, 1
Recommended Clinical Approach
Confirm the patient completed the full 2-dose series with proper timing:
- Both doses administered intramuscularly (not subcutaneously, which would be incorrect for Shingrix) 1
- Second dose given 2-6 months after the first dose (minimum interval 4 weeks) 1, 2
- If the series was completed correctly, no additional doses are indicated 1
If the vaccination series was incomplete or improperly administered:
- If only one dose was received, complete the series with a second dose (vaccine effectiveness is only 56.9% with one dose versus 70.1% with two doses) 6
- If doses were given subcutaneously instead of intramuscularly, consider repeating the series with proper IM administration 1
- If the second dose was given less than 4 weeks after the first, repeat that dose 1
Important Clinical Context
Real-world effectiveness demonstrates protection even without measurable antibodies:
- Two-dose Shingrix effectiveness is 70.1% in preventing herpes zoster in real-world Medicare populations, confirming protection occurs regardless of antibody titers 6
- Protection remains durable for at least 8 years with efficacy above 83.3%, despite potential waning of antibody levels over time 1, 2
The patient remains protected if properly vaccinated:
- Clinical trial data showed 97.2% efficacy in adults aged 50-69 years and 89.8% efficacy in adults ≥70 years, with no requirement for post-vaccination serologic confirmation 2, 3
- Even among immunocompromised patients with potentially reduced immune responses, Shingrix provides meaningful protection without the need for titer verification 6, 3
Critical Pitfalls to Avoid
Do not confuse Shingrix with hepatitis B vaccine protocols. While checking anti-HBs titers after hepatitis B vaccination is standard (with revaccination or higher doses for non-responders), this approach does not apply to zoster vaccination 5
Do not order VZV IgG antibody testing as a surrogate for vaccine response. VZV IgG indicates past varicella infection or vaccination but does not measure Shingrix-induced protection 5, 1
Do not administer additional doses beyond the 2-dose series. No booster doses are recommended or studied, and there is no evidence that additional doses benefit patients with undetectable antibodies 1, 7
Special Considerations
If the patient is immunocompromised:
- Shingrix is safe and indicated for immunocompromised adults aged ≥18 years, though immune responses may be somewhat reduced 5, 1, 3
- Even with potentially lower immunogenicity, the vaccine provides clinically meaningful protection, and additional doses are not recommended based on absent titers 6, 3
- The 2-dose series should be completed with doses 1-2 months apart for immunocompromised patients (shorter interval than immunocompetent patients) 1, 8
Reassure the patient about ongoing protection: