Does the pneumococcal (Pneumococcal Conjugate Vaccine) 23 vaccine need to be repeated?

PPSV23 Vaccination: Does It Need to Be Repeated?

For adults aged ≥65 years who received PPSV23 at age ≥65, no additional doses of PPSV23 are needed, but a single dose of PCV20 should be administered at least 1 year after the last PPSV23 dose to complete the pneumococcal vaccination series. 1

Current Recommendation Based on 2023-2024 ACIP Guidelines

The pneumococcal vaccination landscape has fundamentally changed with the introduction of newer conjugate vaccines (PCV20, PCV21, PCV15) that provide broader serotype coverage and superior immunologic responses compared to PPSV23 alone. 1

For Adults Who Received PPSV23 at Age ≥65 Years:

• No additional PPSV23 doses are recommended - the single dose given at age ≥65 is sufficient for PPSV23 coverage. 1
• However, you should now receive PCV20 (or PCV15 followed by PPSV23) at least 1 year after your last PPSV23 dose to provide comprehensive protection. 2, 1
• This completes your pneumococcal vaccination series, and no further pneumococcal vaccines will be needed. 1, 3

Rationale for Adding PCV20:

• Conjugate vaccines like PCV20 provide T-cell dependent immunity with immunologic memory, unlike PPSV23 which acts through T-cell independent mechanisms. 2, 3
• PCV20 covers 20 serotypes with superior immune responses compared to the polysaccharide-only approach of PPSV23. 3
• Studies demonstrate that PCV vaccines are more immunogenic than PPSV23, particularly in high-risk populations. 2

Special Considerations for High-Risk Patients

If You Have Immunocompromising Conditions:

For patients with chronic renal failure, HIV infection, malignancies, immunosuppressive therapy, asplenia, or transplant recipients:

• PPSV23 may require repeat dosing every 5 years if the first dose was given before age 65. 2, 1
• However, the preferred modern approach is to add PCV20 at least 1 year after the last PPSV23 dose, which then completes the series. 1, 3
• For immunocompromised patients who received both PCV13 and one dose of PPSV23 before age 65, a second PPSV23 dose may be given ≥5 years after the first PPSV23 dose. 1

Duration of PPSV23 Protection:

• PPSV23 effectiveness declines significantly over time, dropping from 48% at ≤2 years post-vaccination to 15% at ≥5 years. 2
• This declining protection is one reason why adding a conjugate vaccine (PCV20) is now recommended rather than simply repeating PPSV23. 2, 1

Critical Timing Intervals

• Minimum 1-year interval between PPSV23 and subsequent PCV20 for immunocompetent adults. 1, 3
• For immunocompromised patients, the interval between PCV and PPSV23 can be shortened to 8 weeks (not applicable in reverse order). 1, 3
• If both PCV13 and PPSV23 were previously received, PCV20 may be considered through shared clinical decision-making ≥5 years after the last dose. 1, 3

Common Pitfalls to Avoid

• Do not give multiple PPSV23 boosters beyond what is recommended - there is insufficient evidence for safety with three or more doses, and concerns exist about immune hyporesponsiveness. 2, 1, 4
• Do not delay adding PCV20 - the 1-year minimum interval after PPSV23 should be observed, but once met, proceed with vaccination. 1, 3
• After receiving PCV20, do not add PPSV23 - the series is complete and no additional pneumococcal vaccines are needed. 1, 3

Evidence on Repeat PPSV23 Administration

While older guidelines recommended PPSV23 revaccination every 5 years for high-risk patients, concerns about immune hyporesponsiveness have emerged:

• Repeat PPSV23 administration may induce lower immune responses than initial vaccination when intervals are <5 years. 2
• A systematic review found that revaccination with PPSV23 might induce lower short-term immune responses, though antibody levels measured >2 years after vaccination were sometimes higher after revaccination. 2
• One study in Uganda raised concerns about potential harm from PPSV23 revaccination in HIV-infected adults, hypothesizing destruction of polysaccharide-responsive B-cell clones. 2

The modern approach prioritizes conjugate vaccines (PCV20) over repeated PPSV23 dosing because conjugate vaccines provide superior immunologic responses without the risk of hyporesponsiveness. 2, 1, 3