What are the guidelines for using Pneumococcal Polysaccharide Vaccine (PPSV23) in a healthy 1-2 year old child who has received three prior doses of Pneumococcal Conjugate Vaccine (PCV), considering the introduction of PCV20?

PPSV23 is NOT Recommended for Healthy 1-2 Year Olds After PCV Vaccination

For a healthy child aged 1-2 years who has received three prior doses of PCV (whether PCV13 or PCV20), PPSV23 is not indicated—complete the fourth dose of pneumococcal conjugate vaccine at 12-15 months and no further pneumococcal vaccination is needed. 1, 2

Standard Schedule for Healthy Children

The ACIP guidelines are clear that healthy children require only the 4-dose PCV series without any PPSV23:

• Complete the conjugate vaccine series: A child who received 3 doses before 12 months should receive their fourth dose at 12-15 months, at least 8 weeks after the third dose 1
• No PPSV23 needed: Healthy children who complete the 4-dose PCV series maintain protection throughout childhood without requiring PPSV23 or booster doses after age 5 years 2
• PCV20 consideration: While PCV20 is newer than the 2010 guidelines, the same principle applies—complete the conjugate vaccine series appropriate for the child's age, and healthy children do not require polysaccharide vaccine 2

When PPSV23 IS Indicated in Children

PPSV23 is reserved exclusively for high-risk children aged ≥2 years with specific medical conditions 1, 3:

• Immunocompromising conditions (HIV infection, chronic renal failure, nephrotic syndrome, immunosuppressive therapy, malignancy) 3, 2
• Anatomic or functional asplenia (including sickle cell disease) 3, 4
• Cochlear implants 3, 4
• Cerebrospinal fluid leaks 3, 4

Critical Timing for High-Risk Children

If your patient develops a high-risk condition, the sequence matters:

• Always give PCV13 first, then PPSV23 at least 8 weeks later 3, 5
• For high-risk children aged 24-71 months who received <3 doses of PCV before age 24 months: give 2 doses of PCV13 (8 weeks apart), then PPSV23 at least 8 weeks after the final PCV13 dose 3, 2
• Never reverse this order: Giving PPSV23 before PCV13 can impair the subsequent response to PCV13 due to hyporesponsiveness 1, 3

Common Pitfalls to Avoid

• Do not give PPSV23 to healthy children <2 years: It is neither immunogenic nor indicated in this population 1, 2
• Do not confuse "incomplete series" with "needs PPSV23": An incomplete PCV series means completing the conjugate vaccine doses, not adding PPSV23 1
• Do not assume all children need both vaccines: The vast majority of healthy children only need the PCV series 2

Algorithm for Your 1-2 Year Old Patient

1. Verify vaccination history: Count total PCV doses received
2. Assess health status: Is the child healthy or do they have high-risk conditions?
3. If healthy with 3 prior doses: Give fourth PCV dose at 12-15 months (≥8 weeks after dose 3), then done 1
4. If high-risk: Complete PCV series first, then add PPSV23 at age ≥2 years, ≥8 weeks after final PCV dose 3, 2

The introduction of PCV20 does not change this fundamental principle: healthy children complete their conjugate vaccine series and do not require polysaccharide vaccine 2.