Conjugate vaccines that contain 10 (PCV-10), or 13 (PCV-13) pneumococcal serotypes are currently available. A pneumococcal conjugate vaccine containing 7 serotypes (PCV-7) is gradually being removed from the market.
Indication and administration
Although the exact labelling details may differ by country, both PCV10 and PCV13 are licensed for immunization of infants and children from 6 weeks to 5 years of age against invasive disease, pneumonia and acute otitis media caused by the respective vaccine serotypes of S. pneumoniae. In addition, PCV13 is licensed for the prevention of pneumococcal disease in adults >50 years of age. For PCV administration to infants, WHO recommends three primary doses (given at 6, 10 and 14 weeks or 2, 4 and 6 months) or two primary doses plus a booster (given between the age of 9 and 15 months). The favourable safety and reactogenicity profiles of pneumococcal conjugate vaccines are well established, and compatibility with major childhood vaccines has been demonstrated.
The 23-valent polysaccharide vaccine (PPV23) represents pneumococcal serotypes that are responsible for 85–90% of invasive pneumococcal infections in USA and some other industrialized countries. The vaccine is efficacious against invasive pneumococcal disease and pneumonia in healthy young adults but shows limited efficacy in this regard in other age groups. PPV23 is licensed only for individuals aged >2 years. The vaccine is commonly recommended for children and adults who have certain underlying medical conditions predisposing for pneumococcal infection, although its efficacy in several of these conditions is not well documented. In some countries, such as USA, routine vaccination is recommended for everyone over 65 years of age.
For primary immunization, PPV23 is administered as a single intramuscular dose (preferably in the deltoid muscle) or as a subcutaneous dose. The optimal timing, frequency and clinical effectiveness of additional doses of PPV23 are poorly defined, and national recommendations regarding revaccination vary. However, on the basis of data on the duration of vaccine-induced protection, WHO suggests one single revaccination >5 years after a first vaccination. In resource-limited settings where there are many competing health priorities, evidence does not support routine immunization of elderly people and high-risk populations with PPV23. Local adverse reactions may be more frequent in recipients of a second dose of PPV23 but are generally self-limiting and not severe.