Predicting the impact of new pneumococcal conjugate vaccines: serotype composition is not enough

Expert Rev Vaccines. 2015 Mar;14(3):413-28. doi: 10.1586/14760584.2015.965160. Epub 2014 Sep 30.


Streptococcus pneumoniae is a major cause of childhood morbidity and mortality worldwide. A heptavalent polysaccharide-protein conjugate vaccine (PCV) has proven highly effective in preventing pneumococcal disease in industrialized countries. Two higher-valent pneumococcal conjugate vaccines are now widely available, even in the poorest countries. These differ from each other in the number of serotypes and carrier proteins used for their conjugation. Some have assumed that the only meaningful clinical difference between PCV formulations is a function of the number of serotypes each contains. A careful review of recent clinical data with these and several unlicensed PCV formulations points to important similarities but also that some key properties of each vaccine likely differ from one another.

Keywords: acute otitis media; cross-protection; cross-reactivity; herd protection; higher-valent vaccines; invasive pneumococcal disease; nasopharyngeal carriage; pneumococcal conjugate vaccines; pneumococcus; pneumonia; serotype replacement.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Antigens, Bacterial / immunology*
  • Carrier State / epidemiology
  • Carrier State / microbiology
  • Carrier State / prevention & control
  • Cross Protection
  • Cross Reactions
  • Humans
  • Immunity, Herd
  • Pneumococcal Vaccines / administration & dosage
  • Pneumococcal Vaccines / immunology*
  • Serogroup
  • Streptococcal Infections / epidemiology
  • Streptococcal Infections / microbiology
  • Streptococcal Infections / prevention & control*
  • Streptococcus pneumoniae / immunology*
  • Streptococcus pneumoniae / isolation & purification
  • Vaccines, Conjugate / administration & dosage
  • Vaccines, Conjugate / immunology


  • Antigens, Bacterial
  • Pneumococcal Vaccines
  • Vaccines, Conjugate