Streptococcus are a round to ovoid, gram-positive, often pathogenic bacterium of the genus Streptococcus that occurs in pairs or chains, many species of which destroy red blood cells and cause various diseases in humans, including erysipelas, scarlet fever and strep throat.
Streptococcus, any of a group of gram-positive bacteria, genus Streptococcus, some of which cause disease. Streptococci are spherical and divide by fission, but they remain attached and so grow in bead-like chains. The incidence and severity of streptococcal diseases decreased dramatically after the introduction of antibiotics (penicillin, erythromycin, and selected cephalosporins are all effective against it), but the medical community was shaken by the arrival in the late 1980s of several severe forms of streptococcal infection and by the emergence of several drug-resistant strains.
In addition to strep throat, members of this genus are responsible for many cases of meningitis, bacterial pneumonia, endocarditis, and even necrotizing fasciitis. It should be noted that many streptococcal species are harmless.
Streptococci are part of the normal bacteria of the mouth, skin, intestine and upper respiratory tract of humans.