Pneumococcal Vaccination Sequence: PPSV23 as First Dose
No, PPSV23 (pneumococcal polysaccharide vaccine) should not be administered as the first dose in the pneumococcal vaccination sequence. The Advisory Committee on Immunization Practices (ACIP) recommends that pneumococcal conjugate vaccine (PCV) should be administered first, followed by PPSV23 after an appropriate interval 1.
Recommended Vaccination Sequence
- For all adults who need both types of pneumococcal vaccines, the conjugate vaccine (PCV21, PCV20, or PCV15) should be administered first, followed by PPSV23 if indicated 2, 1
- This sequence optimizes the immune response, as conjugate vaccines induce a T cell-dependent immune response that can enhance the response to subsequent polysaccharide vaccines 3
- When PPSV23 is administered first, it can impair the immune response to subsequent PCV administration, resulting in lower antibody levels 4, 5
Specific Timing Recommendations
- For non-immunocompromised adults: PCV followed by PPSV23 with ≥1 year interval 1, 6
- For immunocompromised adults: PCV followed by PPSV23 with ≥8 weeks interval 2, 1
- For adults ≥65 years with no prior pneumococcal vaccination: Start with PCV21, PCV20, or PCV15; if PCV15 is used, follow with PPSV23 ≥1 year later 2, 7
What To Do If PPSV23 Was Given First
If PPSV23 was inadvertently administered as the first dose:
- Wait ≥1 year after PPSV23 before administering PCV21, PCV20, or PCV15 2, 1
- This extended interval helps minimize the hyporesponsiveness that can occur when PCV is given too soon after PPSV23 5, 3
Impact on Immune Response
- Studies show that initial vaccination with PPSV23 can diminish the response to subsequent administration of PCV13 4, 3
- The diminished immune response after initial PPSV23 vaccination persists for at least 1 year 5
- OPA (opsonophagocytic activity) titers are significantly higher when PCV is given first compared to when PPSV23 is given first 3
Special Considerations
- For patients with immunocompromising conditions, the interval between PCV and PPSV23 should be shortened to ≥8 weeks to ensure protection as quickly as possible 2, 1
- For patients planning elective splenectomy, immunocompromising therapy, or cochlear implant placement, pneumococcal vaccination should be completed at least 2 weeks before the procedure 2
Recent Updates to Recommendations
- The 2024 ACIP guidelines now include PCV21 as an option, which contains eight additional pneumococcal serotypes not included in previously recommended vaccines 2, 7
- For many adults, a single dose of PCV21 or PCV20 may be sufficient without the need for PPSV23 2, 7
Following these evidence-based recommendations ensures optimal immune response and protection against pneumococcal disease, which directly impacts morbidity and mortality outcomes.