Brand new urethra in sexes is relatively gently colonized, even if Staph

New flowers of your pharynx and you will windpipe include each other ?- and you will ?-haemolytic streptococci and additionally enough anaerobes, staphylococci (together with Staph. aureus), Neisseria and you may diphtheroids. The new respiratory tract is sometimes some sterile, despite the normal intake regarding bacteria because of the respiration. not, good numbers of medically normal someone could possibly get bring the new fungus Pneumocystis jirovecii (previously called P. carinii) in their lungs.

The stomach normally harbours only transient organisms, its acidic pH providing an effective barrier. However, the gastric mucosa may be colonized by acid-tolerant lactobacilli and streptococci. Helicobacter pylori, which can cause gastric ulcers (see 22), is carried without symptoms by large numbers of people, the bacterium being in mucus and neutralizing the local acidic environment. The upper intestine is only lightly colonized (10 4 organisms/g), but populations increase markedly in the ileum, where streptococci, lactobacilli, enterobacteriaceae and Bacteroides may all be present. Bacterial numbers are very high (estimated at 10 11 /g) in the large bowel, and many species can be found (Fig. 8.dos). The vast majority (95–99%) are anaerobes, Bacteroides being especially common and a major component of faecal material; E. coli is also carried by most individuals. Bacteroides and E. coli are among the species capable of causing severe disease when transferred into other sites in the body. Harmless protozoans can also occur in the intestine (e.g. Entamoeba coli) and these can be considered as part of the normal flora, despite being animals. Continue Reading