The pneumococcal vaccine is a vaccine that protects against infections caused by the bacterium Streptococcus pneumoniae, including pneumonia, meningitis, and sepsis. There are two main types of pneumococcal vaccines: conjugate vaccines (PCVs) and polysaccharide vaccines (PPSV).
Types of Pneumococcal Vaccines
- Conjugate Vaccines (PCVs): These vaccines link polysaccharides from the bacteria to a protein to provoke a stronger immune response, including memory B cells and mucosal immunity. Examples include PCV13, PCV15, PCV20, and PCV21. They are effective in young children and reduce colonization and antimicrobial resistance.
- Polysaccharide Vaccine (PPSV23): Contains purified polysaccharides from 23 pneumococcal strains. It is mostly used in adults but is not effective in children under 2 or people with weakened immune systems. It induces immunity primarily through IgM release but lacks the long-lasting immune response.
Who Should Get Vaccinated
- Children: Routine vaccination starting at 2 months, with multiple doses recommended in the first year of life. Newer vaccines protect against more strains.
- Older adults: Especially those aged 65 or older, to protect against serious pneumococcal infections.
- People at higher risk: Those with chronic health conditions, weakened immune systems, or certain lifestyle exposures.
Protection and Side Effects
- The vaccine offers protection against severe pneumococcal disease, including forms of meningitis and pneumonia.
- Protection from conjugate vaccines can be long-lasting after completing the series of doses.
- Common side effects include redness and pain at the injection site, fever, and irritability in children. Severe allergic reactions are rare.
Global Recommendations
- The WHO recommends conjugate vaccines routinely for children.
- Different countries have vaccination schedules, e.g., the Netherlands and UK give infant doses with boosters.
- Adults at risk and older adults often receive one or more doses of pneumococcal vaccine as part of adult immunization schedules.
In summary, pneumococcal vaccines are a key preventive measure against serious bacterial infections, recommended primarily for young children, the elderly, and those with higher risk of pneumococcal disease.
