In adults, should PCV13 (Prevnar 13) be administered before PPSV23 (Pneumovax 23), and what is the recommended timing for patients ≥65 years and for those <65 years with high‑risk conditions?

Pneumococcal Vaccination: PCV13 vs PPSV23 Sequencing and Timing

Current Recommendations Have Evolved Beyond PCV13/PPSV23

The 2023-2024 ACIP guidelines now prioritize newer conjugate vaccines (PCV20, PCV21, or PCV15) over the older PCV13/PPSV23 sequence for all adults, making the historical PCV13 vs PPSV23 debate largely obsolete in clinical practice. 1, 2

For Adults ≥65 Years Without Prior Vaccination

Administer a single dose of PCV20 (or PCV21) as the preferred option—this completes the pneumococcal vaccination series with no additional doses needed. 1, 2

• Alternative approach: PCV15 followed by PPSV23 at least 1 year later, though this requires a return visit and is less convenient. 1, 2
• The single-dose PCV20 strategy provides broader serotype coverage (20 serotypes) and eliminates the complexity of sequential dosing. 1, 2
• PPSV23 alone is no longer the preferred initial vaccine for adults ≥65 years. 2

For Adults <65 Years with High-Risk Conditions

Adults aged 19-64 years with immunocompromising conditions (chronic renal failure, asplenia, HIV infection, malignancies, immunosuppressive therapy, transplant recipients, complement deficiencies), CSF leaks, or cochlear implants should receive PCV20 as a single dose or PCV15 followed by PPSV23 at least 8 weeks later. 1, 2, 3

Adults aged 19-64 years with chronic medical conditions only (chronic heart disease, chronic lung disease, chronic liver disease, diabetes mellitus, smoking) should receive PCV20 as a single dose or PCV15 followed by PPSV23 at least 1 year later. 1, 2, 3

• The shorter 8-week interval for immunocompromised patients reflects greater urgency for protection in those at highest risk for invasive pneumococcal disease. 1
• Chronic conditions include diabetes, chronic heart/lung/liver disease, alcoholism, and cigarette smoking—current smokers have 2.8-4.1 times the risk for invasive pneumococcal disease. 3

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Historical PCV13/PPSV23 Sequencing (Pre-2021 Guidelines)

When PCV13 Was Still Recommended

From 2014-2019, ACIP recommended all adults ≥65 years receive both PCV13 and PPSV23 in sequence, with PCV13 administered first. 4, 5, 6

The critical timing intervals were:

• For immunocompetent adults ≥65 years: PCV13 first, then PPSV23 at least 1 year later. 4, 5
• For immunocompromised adults (any age ≥19 years): PCV13 first, then PPSV23 at least 8 weeks later. 4, 1, 5
• If PPSV23 was given first: Wait at least 1 year before administering PCV13. 4

Why PCV13 Was Given Before PPSV23

Conjugate vaccines like PCV13 induce T-cell dependent immune responses with immunologic memory, while PPSV23 induces only T-cell independent responses without memory. 7, 6, 8

• Giving PPSV23 first blunts the subsequent response to PCV13—adults who received PPSV23 before PCV13 had diminished immune responses compared to those who received PCV13 first. 9, 7, 8
• Initial vaccination with PCV13 establishes an immune state that results in robust recall responses upon subsequent PPSV23 administration. 8
• In contrast, initial PPSV23 vaccination results in lower responses to subsequent PPSV23 revaccination. 7, 8

2019 Policy Change

In 2019, ACIP changed PCV13 from a routine recommendation to shared clinical decision-making for immunocompetent adults ≥65 years, while maintaining PPSV23 as the universal recommendation. 4, 1

• This reflected the substantial indirect protection from pediatric PCV13 vaccination, which dramatically reduced PCV13-type disease burden in older adults. 4
• PCV13 remained routinely recommended (not shared decision-making) for adults with immunocompromising conditions, CSF leaks, or cochlear implants. 4, 1

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Managing Patients with Prior Vaccination History

If Patient Previously Received Only PPSV23

Administer a single dose of PCV20 (or PCV15) at least 1 year after the last PPSV23 dose—this completes the pneumococcal vaccination series. 1, 2, 3

• This applies to both adults ≥65 years and younger adults with high-risk conditions. 1, 3
• No additional PPSV23 is needed after PCV20 administration. 1, 2

If Patient Previously Received Only PCV13

Administer a single dose of PCV20 at least 1 year after the PCV13 dose—this completes the series. 1, 3

• For immunocompromised patients who received only PCV13, the same ≥1 year interval applies before giving PCV20. 3

If Patient Previously Received Both PCV13 and PPSV23

For adults who completed PCV13 + PPSV23 at age ≥65 years, shared clinical decision-making may be used to consider a single dose of PCV20 at least 5 years after the last pneumococcal vaccine dose—this is optional, not routine. 1, 3

• This represents an optional additional dose for enhanced serotype coverage, particularly for immunocompromised patients. 3
• Once PCV20 is administered, the pneumococcal vaccination series is complete. 1, 3

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Critical Timing Rules to Avoid Errors

Never co-administer PCV and PPSV23 on the same day—this reduces immune response and wastes vaccine. 1, 2

Minimum intervals between pneumococcal vaccines:

• PCV to PPSV23 (immunocompetent adults): ≥1 year 1, 2
• PCV to PPSV23 (immunocompromised adults, CSF leak, cochlear implant): ≥8 weeks 1, 2
• PPSV23 to PCV: ≥1 year for all patients 1, 2
• Between different pneumococcal vaccines when both previously received: ≥5 years 1, 3

For patients requiring elective splenectomy or initiation of immunosuppressive therapy, complete vaccination at least 2 weeks before surgery or therapy initiation. 4, 1

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PPSV23 Revaccination Rules

Adults who receive PPSV23 at age ≥65 years should receive only one dose—no additional PPSV23 doses are recommended after that dose. 4, 1, 10

Adults who received PPSV23 before age 65 for any indication should receive another dose at age ≥65 years if at least 5 years have passed since the previous dose. 4, 1, 10

A second dose of PPSV23 is recommended 5 years after the first dose for persons aged 19-64 years with immunocompromising conditions (chronic renal failure, asplenia, HIV, malignancies, immunosuppressive therapy). 4, 1, 10

• ACIP does not recommend multiple PPSV23 revaccinations beyond what is specified due to uncertainty regarding clinical benefit and safety with three or more doses. 1, 2
• Maximum lifetime PPSV23 doses: 1-2 doses for immunocompetent adults, 2-3 doses for immunocompromised adults. 1

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Common Pitfalls and How to Avoid Them

Pitfall #1: Giving PPSV23 first in vaccine-naïve patients

• Always give conjugate vaccine (PCV20, PCV21, or PCV15) first—PPSV23 given first blunts subsequent conjugate vaccine responses. 9, 7, 8

Pitfall #2: Administering vaccines too close together

• Respect minimum intervals: ≥1 year for immunocompetent adults, ≥8 weeks for immunocompromised patients between PCV and PPSV23. 1, 2

Pitfall #3: Giving unnecessary PPSV23 after PCV20

• Once PCV20 is administered, the series is complete—no additional PPSV23 is needed. 1, 2, 3

Pitfall #4: Delaying vaccination due to missing records

• If vaccination status is uncertain, use verbal history and proceed with vaccination—do not delay. 1
• Administering PCV20 is safe even if the patient may have previously received PPSV23, provided the minimum 1-year interval is observed. 3

Pitfall #5: Giving multiple PPSV23 boosters beyond recommendations

• Avoid giving three or more lifetime doses of PPSV23—insufficient evidence for safety and benefit. 1, 2