What is the pneumococcal vaccination schedule for asplenia?

• A. PPSV23 after PCV13.
• B. PPSV23 followed by PCV13.
• C. PCV13 and PPSV23 (in that order).
• D. No pneumococcal vaccination is needed.

Answer: (C)

Asplenia raises the risk of severe infection from encapsulated bacteria like Streptococcus pneumoniae, so protection relies on two pneumococcal vaccines given in a specific sequence. The conjugate vaccine (PCV13) is given first because it links the polysaccharide to a protein, producing a strong, memory-producing T-cell–dependent immune response. After immune protection from PCV13 is established, the polysaccharide vaccine (PPSV23) is given to broaden coverage to additional serotypes. Administering PPSV23 before PCV13 can blunt the response to PCV13 later, so the recommended approach is PCV13 followed by PPSV23, with appropriate timing between doses. This sequence provides the best protective effect for someone without a spleen.