1. Anhui Center for Surveillance of Bacterial Resistance, Hefei, PR China
2. Institute of Bacterium Resistance, Anhui Medical University, Hefei, PR China
3. Department of Infectious Diseases, the First Affiliated Hospital of Auhui Medical University, Hefei, PR China
4. Department of Infectious Diseases, Chaohu Hospital of Anhui Medical University, Hefei, PR China