From the Guidelines
The second dose of Shingrix should be administered 2 to 6 months after the first dose. This recommendation is based on the guidelines from the CDC, as stated in a study published in Autoimmunity Reviews 1. For optimal protection against shingles, it's essential to complete the full two-dose series.
- The two-dose schedule is necessary because a single dose does not provide the full, long-lasting protection that the complete series offers.
- If more than 6 months have elapsed since the first dose, you should still receive the second dose as soon as possible without restarting the series.
- The vaccine works by boosting your immune system's response to the varicella-zoster virus, and the second dose helps strengthen and prolong this immunity.
- The vaccine is highly effective at preventing shingles when both doses are received according to the recommended schedule, with efficacy rates over 90%.
- It's worth noting that there are no specific guidelines for immunosuppressed individuals at this time, but the general recommendation for healthy adults 50 years and older is to receive two doses of Shingrix, 2 to 6 months apart 1.
From the Research
Recommended Timing for the Second Dose of Shingrix
The second dose of Shingrix, a recombinant zoster vaccine, is recommended to be given 2-6 months after the first dose among adults aged ≥50 years 2.
Flexibility in Second Dose Administration
Studies have shown that administering the second dose beyond the recommended 6 months does not significantly impair the vaccine's effectiveness 2, 3. In fact, one study found that second-dose vaccine effectiveness was not significantly lower for beneficiaries who received their second dose at ≥180 days 2.
Importance of Timely Series Completion
However, timely series completion is still important, as a modest increase in absolute vaccine uptake worldwide was estimated to avert millions of additional herpes zoster cases 3. Greater numbers of averted cases and lower numbers needed to vaccinate were estimated at ideal second-dose compliance, demonstrating the importance of completing the vaccine series in a timely manner.
Series Completion Rates
In the United States, second-dose series completion rates among 50-64-year-olds were found to be around 70% within 6 months and 80% within 12 months of the first dose 4.
Vaccine Efficacy and Safety
The adjuvanted recombinant zoster vaccine has been shown to be well-tolerated and efficacious in preventing herpes zoster in various populations, including Chinese adults ≥50 years 5. However, research into new vaccine strategies, such as the use of a gEgI fusion protein adjuvanted with CpG-emulsion, is ongoing to address concerns regarding safety and accessibility 6.