Toxic Shock Syndrome is most commonly caused by: March 2005

Ans. B: Staphylococcus aureus Toxic shock syndrome (TSS) is caused by the reaction of the human immune system to bacterial superantigens. A defect of protective immunity is postulated to be a major risk factor for recurrence of TSS. Superantigens are produced by various species of coagulase-positive staphylococci, most notably Staphylococcus aureus but also the zoonoses Streptococcus suis (common in pigs), Streptococcus mitis (in mice), and Streptococcus agalactiae. Group A beta-hemolytic streptococci notably (Streptococcus pyogenes) also produce superantigens.