Escherichia coli is an important etiologic agent of lower respiratory tract infections (LRTI). Multidrug-resistant E. coli EC302/04 was isolated from a tracheal aspirate, and its genome sequence is expected to provide insights into antimicrobial resistance as well as adaptive and virulence mechanisms of E. coli involved in LRTI.

e416 15th ICID Abstracts / International Journal of Infectious Diseases 16S (2012) e317-e473 resistant S.aureus is one of the most important nosocomial pathogens with increasing global prevalence in recent 3 decades. Regarding to being carrier, medical students can be considered as one of the infection sources. The aim of this study was to assess the prevalence of nasal carriage of this organismin medical students. Methods: In a cross-sectional study nasal swabs were collected from 466 medical students including 216 preclinical, 179 clinical students and 71 residents. Samples were cultured on blood agar. S. aureus isolates were further analyzed for antibiotic resistance. Each person was questioned for sex, grade, recent disease and drug history and family members' employment in hospital. Results: Of 466 students, 109 (23.4%) were nasal carrier of S. aureus. According to the educational categories, 52 (94.1%) pre-clinical students, 39 (21.7%) clinical students, and 18 (25.3%) residents were carrier. No significant association was observed between nasal carrier rates and educational categories. Most isolates were resistant to penicillin (97.2%), and 53.2% were methicillin-resistant. Most methicillin-resistant strains were isolated from clinical students (76.3%, p<0/001), and most vancomycin-resistant isolates were found in residents (41.2%, p<0/001). Conclusion: The rate of nasal carriage of S.aureus in medical students was similar to general population and hospital personnel, but the rates of MRSA and vancomycin-resistant S. aureus carriers are higher in medical students.