Sievert, D. M. et al. Vancomycin-resistant Staphylococcus aureus in the United States, 2002-2006. Clin. Infect. Dis. 46, 668-674

Michigan Department of Community Health, Lansing, USA.
Clinical Infectious Diseases (Impact Factor: 8.89). 04/2008; 46(5):668-74. DOI: 10.1086/527392
Source: PubMed


This report compares the clinical characteristics, epidemiologic investigations, infection-control evaluations, and microbiologic findings of all 7 of the cases of vancomycin-resistant Staphylococcus aureus (VRSA) infection in the United States during the period 2002-2006.
Epidemiologic, clinical, and infection-control information was collected. VRSA isolates underwent confirmatory identification, antimicrobial susceptibility testing, pulsed-field gel electrophoresis, and typing of the resistance genes. To assess VRSA transmission, case patients and their contacts were screened for VRSA carriage.
Seven cases were identified from 2002 through 2006; 5 were reported from Michigan, 1 was reported from Pennsylvania, and 1 was reported from New York. All VRSA isolates were vanA positive and had a median vancomycin minimum inhibitory concentration of 512 microg/mL. All case patients had a history of prior methicillin-resistant S. aureus and enterococcal infection or colonization; all had several underlying conditions, including chronic skin ulcers; and most had received vancomycin therapy prior to their VRSA infection. Person-to-person transmission of VRSA was not identified beyond any of the case patients. Infection-control precautions were evaluated and were consistent with established guidelines.
Seven patients with vanA-positive VRSA have been identified in the United States. Prompt detection by microbiology laboratories and adherence to recommended infection control measures for multidrug-resistant organisms appear to have prevented transmission to other patients.

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    • "MRSA infection has spread in the past few decades and is treated by vancomycin, the " drug of last resort " [10]. Unfortunately, vancomycin-resistant strains (VRSA) were isolated in June 2002 [11] and there is therefore an urgent need to continuously discover new drugs to combat S. aureus. The type II fatty acid biosynthesis pathway (Fig. 1a), which is usually found in plants and bacteria, is responsible for the de novo production of lipids for incorporation into the bacterial cell membrane [12]. "
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    • "In 2008, a report on isolates from Kolkata (India) was published. There are many reports of VRSA worldwide; most recently the transfer of vanA to MRSA was also reported in Pennsylvania [62] [63] [64] [65] "
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    • "Staphylococcus aureus is a Gram-positive pathogen that is the leading cause of skin, soft tissue, lower respiratory tract and bloodstream infections [1]. Its emerging multiple resistance to antibiotic treatment is becoming a major public health concern [2], [3]. Multiple resistant S. aureus strains, such as MRSA (methicillin resistant S. aureus), have become endemic in many parts of the world [4]. "
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