Streptococci

Last reviewed 12/2022

Streptococci are Gram-positive cocci which form chains.

Classification:

  • by degree of haemolysis - alpha, beta, non-haemolytic
  • by Lancefield grouping

Beta haemolytic types show the most haemolysis. They include Streptococcus pyogenes which is Lancefield group A.

Alpha haemolytic types include viridans Streptococci and Streptococcus pneumoniae.