1.Study On The Epidemiology Of Disinfectant-Resistant Gene QacA In Staphylococcus Aureus 2.Urveillance Of Bacterial Resistance From The First Affiliated Hospital Of Chongqing Medical Nuiversity In 2006

PART 1 STUDY ON THE EPIDEMIOLOGY OF DISINFECTANT- RESISTANT GENE QACA IN STAPHYLOCOCCUS AUREUSBackground:Staphylococcus aureus (SA) is an important pathogen of nosocomial infection and the community infection. More than 100 years ago, the observations and laboratory studies of the disease were begun, but the morbidity and mortality of the disease remain high. Since the 1990s, the prevalence of SA in hospital acquired infection is rising, which has attracted the global attentions. National Nosocomial Infectious Surveillance(NNIS) pointed out that SA is the top cause of hospital acquired infection in the years 1990-1992, especially murtidrug-resistant methicillin-resistant Staphylococcus aureus (MRSA).Human is the natural host of Staphylococcus aureus. according to foreign investigations, the "normal" carrying rate of Staphylococcus aureus in adults is 30% -50%. Rate of staphylococcus aureus infection in patients was higher than in normal persons, up to 40 to 60 percent. The carry rate of Staphylococcus aureus is 83.3% in patients'nasal, which is 50-70% in the hospital staffs, including MRSA and MSSA, and thus these persons were placed in the state of a high risk of infection. In fact, many nosocomial infections are caused through the hands of hospital staffs. It is very important measure to deal with the potential contaminated hands by use disinfectants and sanitizers.It was alarming that the disinfectant and germicide resistance gene qacA and qacB were found in clinical isolates. and the genes encode protein-mediated multi-drug resistance. and the multiple drug resistance has become one treaten of Clinical treatment. Therefore, it is very important to select a reasonable disinfectant to eliminate Staphylococcus aureusObjective:To investigate the disinfectant-resistant gene qacA in Staphylococcus aureus isolates from The First Affiliated Hospital of Chongqing Medical University and control drug-resistance transmission in bacteria.Methods:126 strains were clinically isolated from The First Affiliated Hospital of Chongqing Medical University. The minimum inhibitory concentration (MIC) assay was employed to select disinfectant-resistant strains by using four kinds of representative monovalent and bivalent compounds. Polymerase chain reaction (PCR) was employed to analyze the gene of qacA in these strains. Disk Diffusion for detecting MRSA.Results:Of the 126 Staphylococcus aureus clinical isolates from our hospital in recently years, 12 strains was de tected with qacA gene. The positive rate of gene qacA in SA from our hospital were 9.5%Conclusion:There was high positive percentage of gene qacA in the strains isolated from our hospital. . PART 2 URVEILLANCE OF BACTERIAL RESISTANCE FROM THE FIRST AFFILIATED HOSPITAL OF CHONGQING MEDICAL NUIVERSITY IN 2006BackgroundThe infectious diseases caused by pathogenic microorganisms is a major threat to human health. World Health Organization statistics show that deaths due to infection account for the second place of the total number of deaths and almost half of the deaths ascribe to the developing countries. Antibiotics are the most important medical discovery in 20th century, which play a tremendous role of control human infectious diseases. The advent of penicillin in the 1940s set up a new period of anti-infection treatment, and shortly thereafter, streptomycin, chlorine, erythromycin, tetracycline, and other engaging succession of health care come true which make the infectious diseases mortality rate decreased significantly, taking an effective protection of the people's life and health.Despite the antibiotics of continuous development reduced the infectious disease morbidity and mortality greatly but the emergence and spread of antibiotic resistance is a serious threat of anti-infection treatment efficacy in human. With the economic globalization, antibiotic resistance strains spread internationally. Antibiotic resistance is a global serious problems on account of the irrational use and abuse of antibiotics. Prevention and control of epidemic of antibiotic resistance strains need a variety of interventions, including the rational use of antimicrobial drugs, the surveillance of bacterial resistance.The surveillance of bacterial resistance is organized by Institute of Antibiotics of Huashan Hospital of Shanghai Fudan University. The data were analyzed by WHONET software.Objective To investigate the bacterial resistance of clinical isolates from the first affiliated hospital of Chongqing Medical University in 2006.Methods Antimicrobial susceptibility testing of clinical isolates were performed using Kirby-Bauer methods and the results were analysed according to CLSI/NCCLS 2006.Results Of 574 clinical isolates, gram negative organisms accounted for 72.5% (416/574),gram positive organisms for 27.5% (158/574).The detection rates of methicillin-resistant staphylococci were 63.2% in Staphylococcus aureus and 91.2% in coagulase negative staphylococci(CNS),no vancomycin resistant strains were found. The resistant rates of Enterococcus faecalis and Enterococcus faecium against high level gentamicin were 60% and 90% respectively. ESBLs-producing strains accounted for 44.6% in E.coli and 35.7% in Klebsiella spp.Isolates of Enterobacteriaceae spp. were sensitive to imipenem, while the resistance rates to it was 1.4%～5.9% . However, the resistance rates of Pseudomonas aeruginosa strains to imipenem was higher than 21%.Conclusions Surveillance data of bacterial resistance in our hospital is very important and valuable for the guidance of rational selection of antimicrobial agents to treat bacterial infection in our hospital.