Surveillance of bacterial resistance in China (1998 1999)

Objective To determine the rates of bacterial resistance of clinical isolates obtained from patients with hospital infections (HI) or community acquired infections (CAI) in the study wards of 13 hospitals located at different areas in China. Methods Susceptibility test was performed on 2 081 strains isolated from 13 hospitals, using standard plate dilution method according to the guidelines of NCCLS (1998). MIC 50 and MIC 90 were used to show the antibacterial activity of antimicrobial agents, and data of R%, I% and S% represent resistant, intermediate and susceptible rates of bacteria to antimicrobial agents tested. Results Among total 98 strains of S. aureus , 87 were isolated from patients with CAI and 11 were from HI patients. The incidence of methicillin resistant S.aureus (MRSA) from total infections caused by S. aureus was 27.55%, while the incidence of MRSA from HI patients was 81.82%, which was significantly higher than that (21.84%) from CAI patients. The rate of penicillin resistant S. pneumoniae (PRSP) (R%+I%) was 22.50%; the rate of R (MIC≥2 mg/L) was 2.5%, and most of PRSP strains was intermediate, with I% of 20%. No strains of S. aureus , neither strains of E. faecalis , nor of E. faecium were found resistant to vancomycin. The intermediate rate (I%) of E. faecalis and E. faecium to vancomycin was 3.23% and 3.77%, respectively. Cross resistance of E. coli to quinolones was present obviously, and more than 60% of E. coli strains were resistant to fluoroquinolones tested. Conclusion Multi drug resistance (MDR) of bacteria is a serious problem in China, including MDR of MRSA, PRSP, and enterobacteriaceae; and the resistant rate of enterobacterinceae is the highest up to date.