The Study Of Distribution And Enterotoxin Genes Of Staphylococcus Aureus

Staphylococcus aureus has been considered one of the most important bacteria causing food poisoning, It is in environment far-ranging and has higher resistibility to all kind of physical and chemical factors. The percentage of food poisoning caused by S. aureus is round about 33% of bacterial food poisoning in America, 45% in Canada and more than 50% in some Europe countries such as Hungary, Finland. In our country, there are many cases that are caused by S.aureus.This paper isolated and identified staphylococcus aureus by the first step of the physiologic and biochemical tests from 350 samples. These samples were collected from the maturation of human being,feces of animals,pork,beef,mutton,air,cut hair tools,water and so on. The total detectable rate of staphylococcus aureus is 19.71%。The results show that the detectable rate of staphylococcus aureus are higher. It expresses that pollution level of staphylococcus aureus in Baoding and circumjacent area is taller. Studing distributive condition of these staphylococcus aureus. Studying distributing status of Staphylococcus aureus, it was discovered that the able rate of staphylococcus aureus in cut hair tool samples was the tallest, which indicated that human being has high probability of carrying this bacterium. Among all the food samples, detectable rate of staphylococcus aureus in fresh milk was the highest. It indicated that the probability of this bacterium to pollute milk was high and we should attach importance to quality problem of milk products to avoid breaking out of diseases. Staphylococcus aureus was also detected from the air indicating that Staphylococcus aureus was widely spead so that it was very important to defend the bacterium.Food poisoning caused by Staphylococcus aureus is mainly because of eating food that contains Staphylococcus aureus enterotoxin. At present, Staphylococcus aureus enterotoxin can be divided into 14 types (A,B,C,D,G,H,I,J,K,L,M,N,O)according to serology. Serum type most commonly seen in fulminant food poisoning are A, B and E types. Among 159 Staphylococcus aureus strains, 39 strans contains at least one of enterotoxins SEA, SEB and SEE. 17 strains contained SEA, 20 strains contained SEB, 7 strains contained SEE. 4 strains contained both SEA and SEB and 1 strain contains both SEA and SEE. The study indicated that Staphylococcus aureus which was eparated has high probability of carrying toxin. It is needed that the pollution conditions of staphylococcus aureus in crowd, livestocks and foods as well as epidemiologic conditions of this pathogen are further investigated for the supervision of staphylococcus aureus, the examination of explosion and spread as well as tracking to pollrter to providing basis.