group A streptococcus

group A streptococcus

n.

A common but virulent streptococcus that kills the tissue it infects and produces toxins that trigger a form of shock that affects the vital organs.

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strep throat,

n an infection of the oral pharynx and tonsils caused by hemolytic species of
Streptococcus. The infection is characterized by sore throat, chills, fever, swollen lymph nodes in the neck, and sometimes nausea and vomiting. See also fever, rheumatic.

Streptococcus,

n a bacterium occurring in chains. Produces a zone of greenish discoloration around the colony in blood-agar medium. Part of an individual's normal oral flora; has been isolated from the gingival sulcus. Capable of producing bacterial endocarditis in patients at risk; thus antibiotic prophylactic therapy may be necessary.

Streptococcus,

n a bacterium responsible for causing strep throat and scarlet fever, illnesses that are transmitted primarily through respiratory droplets spread from one person to another by direct contact. Also called
group A Streptococcus.

Streptococcus,

n See Streptococcus, beta-hemolytic.

S. mitis

n a bacterium found on soft tissues of the oral cavity.

S. mutans,

n a cariogenic bacteria found in plaque and one of two index organisms (
Lactobacillus is the other) used to assess caries susceptibility. It is one of a few specialized organisms equipped with receptors for adhesion to the smooth surface of teeth. Sucrose is utilized by it to produce a sticky, extracellular dextran-based polysaccharide that allows them to cohere to each other, thus forming plaque. Conversely, many sugars (glucose, fructose, lactose, sucrose) can be digested by it to produce lactic acid as an end product. It is both aciduric and acidophilic. It is the combination of plaque and acid that leads to smooth surface caries.

S. pneumoniae

n the antigenic type of pneumococci that cause pneumonia and other diseases in humans.

S. pyogenes

n a species of
Streptococcus with many strains that are pathogenic to humans. It causes such suppurative disease as scarlet fever and strep throat.

S. salivarius

n a bacterium found in dental plaque that may cause endocarditis and dental caries.

S. sanguis,

n a bacterium found in dental plaque that may cause endocarditis and dental caries.

S. sobrinus

n a mutans
Streptococcus bacterium the role of which in dental decay is still being determined.

S. viridans

n See Streptococcus, alpha-hemolytic.

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group A streptococcus

Infectious disease A group of bacteria that are normally skin and saprobes of the skin and oral cavity; when pathogenic, GAS spreads by direct person-to-person contact Conditions Strep throat, impetigo, scarlet fever, rheumatic fever, postpartum fever, wound infections, pneumonia; invasive GAS cause necrotizing fasciitis, toxic shock syndrome