The number in the name of the vaccine tells how many strains (bacterial groups, also called serotypes) it protects against.

Antimicrobial resistance and serotypes in Streptococcus pneumoniae have been evolving with the widespread use of antibiotics and the introduction of pneumococcal conjugate vaccines (PCV).

Pfizer PFE is a key player in the PCV vaccine space. PFE markets Prevnar 20, which is approved for the prevention of IPD caused by 20 serotypes in individuals aged six weeks and older. PFE also ...