A detailed description of Staphylococcus aureus and E. coli

(i) Staphylococcus aureusstaphylococcusis the most important pathogenic bacteria in the Staphylocus genus, which often causes purulent inflammation and is the most common pus-pucosisSepsis and sepsis can also be caused, and are the main pathogens of hospital infection1, formthe gram dyed as positive, spherical, diameter of about 1 m, arranged into grape string (Figure 1-10), no buds, no whiplash, can not moveWith the exception of a few strains, the membrane is generally not formedEasy to be colored by commonly used alkaline dyesIts aging, death, or white blood cell swallowing, and certain drug-resistant strains can be dyed to gram-negative2, culture characteristicsaerobic or anaerobicNutritional requirements are not high, in the ordinary medium, 37 degrees C growth is good, in the nutrient-rich medium growth is betterForm a round smooth, neatly, opaque raised colony on a normal agar plate with a diameter of about 2mmThe colonies are golden, the pigment is fat-soluble, so the medium is not colored3, pathogenic-induced diseases:(1) pus infection: pus-based abscess-based inflammation, generally occurred in skin tissue (mainly radon, hair cystic, abscess, honeycomb loomitis, wound pus, etc.), can also occur in deep tissue organs (such as pneumonia, puss, otitis, meningitis, heart inflammation, etc.) (2) toxin diseases: caused by a variety of exotoxins produced by Staphylococcus aureus, mainly food poisoning, pseudo-membrane enteritis, scaldskin syndrome, toxic shock syndrome and so on 4, microbiology testing collected specimens directly smeared, Grameen dyeing mirror test, according to bacterial morphology, arrangement and staining can make a preliminary diagnosis The specimen was inoculated on the blood agar plate, cultured 18 cyao 24h at 37 degrees C, selected the suspected colony for the gram staining mirror examination, and then made the necessary identification test (ii) E coli E coli, commonly known as E coli, is the most important normal bacteria in the human body, generally do not cause disease, when the microbiome disorder, the body's immunity decline or the bacteria invasion of intestinal tissue can cause disease, belong seismost disease Some serotype strains are highly toxic and can cause intraintestinal infections, known as pathogenic E coli 1, morphology Grameum-negative bacillus, size (0.4yew 0.7) sm x (1c 3) sm, most strains have weekly whiplash, bacteria, no buds (Figure 1-1) 2, culture characteristics and biochemical reactions form a color-colored, 3mm diameter smooth colony on the intestinal selective medium Most strains ferment lactose to produce acid production, and ferment glucose, maltose, glycol and other acid-producing gas The results of the test of the typical E coli ethria, methyl red, VP, and pyridine (IMViC) were "----" 3, pathogenic -caused diseases: (1) out-of-the-gut infections: urinary infections (e.g urethritis, cystitis, phytophinitis, etc.) and pus infections (e.g peritonitis, gallbladderitis, appendicitis, etc.) are most common E coli often comes from the patient's intestines and is an endogenous infection (2) intestinal infections (acute diarrhea): Certain serotype of e coli can cause diarrhea in humans According to its pathogenic mechanism, it is divided into five types of enterotoxic e coli, entero-pathogenic E coli, enteroinvasive e coli, enterohemorrhagic e coli, and e coli 4, microbiological testing the intestinal e coli in the intestines constantly excreted with feces, can pollute the surrounding environment, water, food, etc , sampling testing, the sample detected more of this bacteria, indicating that the more serious contamination by feces, but also indirectly indicated that there may be intestinal pathogenic bacteria pollution In environmental health and food and drug hygiene, the total number of bacteria and the number of E coli groups as the detection index of fecal contamination The total number of bacteria is the number of bacteria per milliliter or per gram of samples The number of E coli groups refers to the number of Coliform groups contained in each liter of samples China's health standard is that every 10 ml of drinking water must not detect the total E coli, heat-resistant Coliform and E coli