Objective: To investigate antimicrobial resistance among gram-positive cocci in China in 2009.
Methods: From June to December 2009, 1169 consecutive and non-repetitive gram-positive cocci were collected from 12 teaching hospitals at 9 cities. The minimal inhibitory concentration (MIC) of antibacterial agents was determined by agar dilution method.
Results: The prevalences of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative Staphylococci (MRCoNS) were 45.3% (211/466) and 89.5% (214/239), respectively. The isolation rate of MRSA was 33.3% - 68.1% from different samples. All Staphylococci isolates were susceptible to vancomycin, teicoplanin and linezolid. Five point five percent (7/128) E.faecium strains were resistant to vancomycin. All E. faecalis strains were susceptible to vancomycin. About 99.1% (108/109) of E.faecalis and E.faecium were susceptible to linezolid. The prevalence of penicillin-intermediate Streptococcus pneumoniae (PISP) was 21.6% (48/222). Only 1 (0.5%, 1/222) Streptococcus pneumoniae strain was resistant to penicillin. Teicoplanin, vancomycin, linezolid and tigecycline were the most active agents against Streptococcus pneumoniae (susceptible rate 100%).
Conclusions: The high prevalence of methicillin-resistance is among Staphylococcus strains. Different samples show a different MRSA prevalence. Teicoplanin, vancomycin and linezolid show very high activity to Staphylococci, E. faecalis, E. faecium and Streptococcus pneumoniae.