Pneumococcal and Influenza Vaccination Recommendations for Adults
All adults aged ≥50 years should receive a single dose of pneumococcal conjugate vaccine (PCV20 or PCV21 alone, or PCV15 followed by PPSV23), and all adults aged ≥6 months should receive annual influenza vaccination. 1, 2
Pneumococcal Vaccination
Age-Based Recommendations
Adults aged ≥50 years (PCV-naïve):
- Single dose of PCV20 (preferred for simplicity), OR
- Single dose of PCV21, OR
- PCV15 followed by PPSV23 (≥1 year interval between doses)
This represents a major expansion from the previous age-65 threshold, now capturing adults at age 50 1, 3.
Adults aged 19-49 years:
- Vaccination recommended ONLY if they have specific risk conditions:
- Chronic medical conditions: alcoholism, chronic heart/liver/lung disease, diabetes, smoking
- Immunocompromising conditions: HIV, malignancy, immunosuppressive therapy, chronic renal failure, asplenia, CSF leak, cochlear implant 3
Previously Vaccinated Adults
The algorithm depends on what they received previously 3:
If received PPSV23 only:
- Give PCV20 (or PCV15) after ≥1 year interval from last PPSV23
If received PCV13 only:
- Give PCV20 after ≥1 year interval, OR
- Give PPSV23 after ≥8 weeks interval (then reassess at age 65)
If received both PCV13 and PPSV23 (but PPSV23 before age 65):
- Give PPSV23 again at age ≥65 (≥5 years after last PPSV23)
If received both PCV13 and PPSV23 at age ≥65:
- Shared clinical decision-making for supplemental PCV20 dose (≥5 years after last dose) 3
Special Population: Hematopoietic Stem Cell Transplant
These patients require a complete re-vaccination series 3:
- 3 doses of PCV (4 weeks apart, starting 3-6 months post-transplant)
- Fourth dose ≥6 months after third dose OR ≥12 months post-transplant (whichever is later)
- If chronic GVHD present: give fourth PCV dose instead of PPSV23
Influenza Vaccination
Universal Annual Recommendation
All persons aged ≥6 months should receive annual influenza vaccination unless contraindicated 2.
Timing Considerations
Optimal timing (September-October):
- Most adults should receive vaccination during September or October to balance early protection against potential waning immunity 2
Special timing considerations:
- Adults aged ≥65 years and pregnant women: Should NOT receive vaccination in July-August due to concerns about waning immunity before peak influenza season 2
- Vaccination should continue throughout the influenza season as long as virus is circulating
Formulation Requirement (NEW 2025)
Critical update: Children aged ≤18 years, pregnant women, and all adults should receive only thimerosal-free, single-dose formulations 2.
Key Clinical Pitfalls
Don't delay pneumococcal vaccination waiting for age 65—the threshold is now 50 years 1
Minimum intervals matter:
- PCV-to-PPSV23: ≥1 year (for most indications)
- PCV13-to-PPSV23: ≥8 weeks acceptable in some scenarios
- Between PPSV23 doses: ≥5 years 3
Don't give influenza vaccine too early (July-August) to older adults—immunity may wane before peak season 2
Smoking is a pneumococcal vaccination indication for adults 19-64 years—often overlooked 3
Both vaccines can be given simultaneously at different anatomic sites—no need to separate visits 4
Evidence Quality
The pneumococcal recommendations are based on 2023-2024 ACIP guidelines using GRADE methodology 3, 1, representing the highest quality evidence available. The age-50 expansion was approved October 2024 1. The influenza recommendations represent 2025-26 ACIP guidelines 2, with the thimerosal-free requirement being a June 2025 update.
The combined use of both vaccines shows mortality benefit beyond individual vaccine effects, with adjusted relative risk of 0.46 for mortality when both are administered 5, supporting aggressive implementation of both recommendations.