What is the Pneumococcal Vaccine?
The pneumococcal vaccine is a preventive immunization that protects against invasive disease caused by Streptococcus pneumoniae (pneumococcus), a bacterial pathogen responsible for bacteremia, meningitis, pneumonia, and other serious infections that result in significant morbidity and mortality, particularly in older adults and those with chronic medical conditions. 1
Types of Pneumococcal Vaccines
There are two main categories of pneumococcal vaccines currently available:
Pneumococcal Conjugate Vaccines (PCVs)
- PCV20 (20-valent) and PCV21 (21-valent) are the newest conjugate vaccines, covering 20 and 21 pneumococcal serotypes respectively 1
- PCV15 (15-valent) covers 15 serotypes and can be used in series with PPSV23 1
- These conjugate vaccines generate stronger immune responses and immunological memory compared to polysaccharide vaccines 2
Pneumococcal Polysaccharide Vaccine
- PPSV23 (23-valent) contains purified capsular materials from 23 pneumococcal serotypes responsible for 88% of bacteremic pneumococcal disease 1
- This vaccine has been in use since the 1980s but does not generate immunological memory as effectively as conjugate vaccines 1
Who Should Receive Pneumococcal Vaccination
All Adults ≥65 Years
Every adult aged 65 years and older should receive pneumococcal vaccination with either PCV20 alone, PCV21 alone, or PCV15 followed by PPSV23 1. The 2024 ACIP recommendations expanded this to include all adults ≥50 years who have not previously received a PCV 3.
Adults 19-64 Years with Risk Conditions
Adults in this age group should receive pneumococcal vaccination if they have any of the following conditions 1:
Chronic Medical Conditions:
- Chronic cardiovascular disease (congestive heart failure, cardiomyopathies) 1
- Chronic pulmonary disease (COPD, emphysema, but not asthma alone) 1
- Diabetes mellitus 1
- Chronic liver disease or cirrhosis 1
- Alcoholism 1
- Cerebrospinal fluid leaks 1
Immunocompromising Conditions:
- Functional or anatomic asplenia (including sickle cell disease) 1
- Chronic renal failure or nephrotic syndrome 1
- HIV infection or AIDS 1
- Congenital or acquired immunodeficiency 1
- Hodgkin disease, lymphoma, leukemia, or multiple myeloma 1
- Generalized malignancy 1
- Solid organ transplantation 1
- Immunosuppressive therapy (long-term corticosteroids, chemotherapy) 1
Vaccine Administration
Pneumococcal vaccine is administered as a single 0.5-mL dose either intramuscularly or subcutaneously 1. The vaccine can be given simultaneously with influenza vaccine using separate injection sites without increased side effects or decreased antibody response 1.
Clinical Effectiveness
The pneumococcal vaccine is highly effective at preventing invasive pneumococcal disease (bacteremia, meningitis), with vaccine effectiveness ranging from 60-81% against bacteremic disease in adults 1. A meta-analysis demonstrated efficacy in reducing bacteremic pneumococcal pneumonia among low-risk adults 1. However, the vaccine does not protect against disease caused by non-vaccine serotypes 1.
For immunocompromised patients, effectiveness data are more limited, though vaccinated patients with sickle cell disease or splenectomy experienced significantly less bacteremic disease than unvaccinated patients 1.
Vaccination Timing Considerations
For patients undergoing elective surgery, pneumococcal vaccine should ideally be administered ≥2 weeks before the procedure to allow adequate immune response 4. For immunocompromised patients requiring the PCV15 + PPSV23 series, PPSV23 should be given ≥8 weeks after PCV15, whereas immunocompetent patients should wait ≥1 year between doses 1, 4.
Cost-Effectiveness
Pneumococcal vaccination is cost-effective and potentially cost-saving among persons aged ≥65 years for prevention of bacteremia, comparing favorably with other standard preventive practices 1.