Group A streptococcus (GAS)

Group A Streptococcus (GAS) spreads through respiratory droplets and skin contact. It causes common illnesses like strep throat and impetigo, in severe case necrotizing fasciitis and toxic shock syndrome. 

Invasive GAS (IGAS) occurs when the bacteria proliferate in a normally sterile body site, such as the blood, soft tissues or joints. 

Streptococcal toxic shock syndrome (STSS) can be a severe complication of IGAS, caused by toxins that are produced by GAS, which act on host cells or tissues.