الفهرس 
Introduction and aim of the work
Implications of vancomycin resistant staphylococcus au reusOnly 14 pages are availabe for public view
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Abstract
Methicillin resistant Staphylococcus aureus (MRSA) has emerged and spread globally over the years since the first clinical use of methicillin. Once MRSA is introduced into a hospital, it usually becomes endemic, despite the implementation of infection control measures. Resistance of staphylococci to several antimicrobial agents contributes to their ability to survive in the hospital environment and to spread among patients. This is the case for MRSA which is usually resistant not only to penicillins and cephalospirns but also to aminoglycosides, tetracyclines and often quinolones and rifampin as well. Multiple antibiotic resistance, however is not the only factor which contributes to the ability of staphylococci to spread in hospitals. Epidemic MRSA strains are defiend as having caused hospital outbreats involving at least two patients or staff members in one or more hospitals. MRSA strains that were isolated only once were defined as nonepidemic or sporadic. In another words, epidemic strains of MRSA are defined as those which have been identified in two or more patients in two or more hospitals. The first epidemic MRSA strain (EMRSA) strain, designated EMRSA-1, was recognized in 1981 and continued to cause outbreaks in hospitals until the late 1980s. A second EMRSA strain, EMRSA-2, emerged in the late 1985 and was followed closely by 12 other EMRSA strains described during a survey carried out in 1987 and 1988. EMRSA-15 emerged during 1991 and rapidly displaced most of other EMRSA strains, followed by EMRSA-16 which was discovered in the mid 1990s. Identifying outbreak isolates is a major step in determining the source of the outbreak and in designing subsequent control measures. Two typing techniques frequently used for strains delineation of S.aureus are bacteriophage typing (BT) and pulsed field gel electrophoresis (PFGE).