normal flora


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Related to normal flora: resident flora

normal flora

See flora.

nor·mal flor·a

(nōr'măl flōr'ă)
Microorganisms that normally reside at a given site and under normal circumstances do not cause disease.

normal flora

Microorganisms including bacteria, protozoa, and fungi that are found on or in specific areas of the body. The skin and mucous membranes of the oral cavity, intestines, upper respiratory tract, and vagina have specific, permanent flora. They are harmless, even beneficial, in their usual sites, and they inhibit the growth of pathogens, but they can cause infection if they are introduced into unusual sites. If the proportions of the various microorganisms are disrupted, one species may overgrow, as does Candida when bacterial flora are diminished by antibiotics. Synonym: resident flora See: colitis, pseudomembranous; infection; microorganism

The largest concentration of bacteria in humans is in the colon, where more than 400 genera may coexist. In the colon, anaerobic bacteria outnumber aerobic bacteria 1000:1, and there may be 1011 per g of fecal material. The anaerobic gram-positive lactobacilli may be concentrated in the vagina at the 105 to 108/ml level, but 20% of women have no detectable anaerobes in the vagina. In dental plaque and gingival sulci, the bacteria may reach a concentration of 1012/ml.

See also: flora

Normal flora

The mixture of bacteria normally found at specific body sites.
References in periodicals archive ?
This could indicate that, in the cases where disease was present, the normal flora became opportunistic pathogens.
jensenii are the most common species in Latvian pregnant women normal flora, that does not differ from the Finnish and Japanese data.
mutans without disturbing other normal flora, create an environment with a higher resting plaque pH, lower lactic acid production and significantly reduce enamel demin-eralization.
Ulusal Cocuk Enfeksiyon Hastaliklari Kongresi'nde sunduklari bir olguda ciddi EN tanisi konulan 9 yasindaki bir cocukta ilk bogaz kulturu normal flora bildirilmesine ragmen, tedavi oncesi tekrar edilen ikinci bogaz kulturunde A grubu beta hemolitik streptokok uremistir (4) bu nedenle taniyi kesinlestirmek icin usulune uygun kultur alinmasi cok onemlidir.
It pretty much takes over your normal flora," said Trent.
To the Editor: Granulicatella and Abiotrophia, formerly known as nutritionally variant streptococci, are normal flora of the human upper respiratory, gastrointestinal, and urogenital tracts (1).
Do they realize that their techs are reporting out normal flora organisms with susceptibility results, and providers are making patient-management decisions based on that information?
necrophorum, an anaerobic bacteria that is part of the normal flora of the oropharynx, but is capable of producing toxins that can dissect fascial planes and stimulate platelet aggregation.
This happens when a particularly virulent pathogen is encountered, or when a large number of organisms are introduced into a site or overgrow as a result of disturbance of normal flora.
The key to prevention of CDAD is to first prevent the acquisition of Clostridium difficile and its spore, and secondly, to prevent the over use of antibiotics, thereby protecting the patient's intestinal normal flora.