Location and media preference: grow on blood agar, normal flora of 15% in nares, hands, axilla, perineum. Toxins: cytotoxins to many cells, haemolysins, enterotoxins. Cause of food poisoning: exfoliative toxins. Scalded skin syndrome in children: toxic shock syndrome toxin 1. Used to differentiate s aureus from other staphylococcus species: -lactamase, hyaluronidase. Clinical findings: produce purulent infections, complications can be pneumonia, septicemia, endocarditis, other diseases are food poisoning (enterotoxin), toxic shock syndrome. Resistance: 90% of strains in hospital resistance to penicillin. Prevention: education of mode of transmission, strict use of aseptic techniques in or and er. Location and media preference: normal flora of skin and mucous membranes, non-pathogenic. Clinical findings: post-operative infections after brain or open heart surgery, endocarditis after heart valve insertion, may cause necrotizing enterocolitis. General information: 5-10% of people are carriers, nasal carriers most likely to transmit, lancefield group a, -hemolytic. Neutrophils and macrophages: streptococcal pyrogenic exotoxins (spe) Clinical findings: acute tonsillitis, fever, skin infection.