The most common human pathogenic Staphylococci are S. aureus , S. epidermidis , and S. saprophyticus . S. aureus , S. intermedius , and S. hyicus are common opportunistic pathogens of animals. S. aureus most often causes localized skin infections, the most common bacterial infections. It can also infect the eye, nose and throat, urethra, vagina, and gastrointestinal tract. Scalded skin syndrome is usually seen in children and is due to exfoliating toxin.
Infected skin becomes bright red and peels, and blisters also appear.
TSS has been associated with the use of highly adsorbent tampons but can occur in other Staphylococcus infections. S. epidermidis is the second most common Staphylococcus found in the nose. S. epidermidis is also a common cause of peritonitis in people on renal dialysis and of infections of replacement heart valves. The pathogenic Streptococci can also be found as normal flora, usually in the upper respiratory, gastrointestinal, and urogenital tracts. Streptococci are somewhat more fastidious than Staphylococci and not salt-tolerant.