Objective: To investigate antimicrobial resistance of common community respiratory pathogens isolated in China, 2002 - 2003.
Methods: 779 strains of Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Group A beta-haemolytic Streptococci and oxacillin-susceptible Staphylococcus aureus (MSSA) were isolated from patients with community-acquired respiratory tract infections at 5 hospitals in China from April 2002 to 2003. Meanwhile, 185 strains of S. pneumoniae, H. influenzae and M. catarrhalis were isolated from nasopharynx swabs at 2 day-care centers in Beijing. Agar dilution method was used to determine the minimal inhibitory concentration (MICs) of cefprozil and other 9 antibiotics against these strains.
Results: The prevalence of penicillin-intermediate S. pneumoniae (PISP) was 23.9% and that of penicillin-resistant S. pneumoniae (PRSP) was 22.7% at 5 cities in China. The prevalence of PISP were 44.1% in Hangzhou, 26.2% in Wuhan, 21.5% in Shenyang, 20.8% in Shanghai, 18.5% in Beijing, and 12.7% at day-care centers in Beijing;the prevalance of PRSP were 34.9% in day-care centers, 31.9% in Shanghai, 27.9% in Wuhan, 22.1% in Hangzhou, 13.8% in Shenyang and 8.6% in Beijing. The susceptible rate of levofloxacin in S. pneumoniae was 96.3%. 9.5% of H. influenzae and 87.4% of M. catarrhalis produced beta-lactamases. The susceptibility of amoxicillin/clavulanate, cefaclor, cefprozil, cefuroxime, ceftriaxone, azithromycin, and levofloxain in these two species ranged from 96.4% to 100%. The resistance rate of azithromycin in S. pneumoniae was higher than 60%. Cefprozil MICs against PISP, Group A beta-haemolytic Streptococci and MSSA were 4 - 16 fold lower than cefaclor.
Conclusions: Antimicrobial resistance in respiratory pathogens, especially S. pneumoniae is increasing. It brings concerns that high macrolide resistance was found in gram-positive cocci. Cefprozil was more active than cefaclor against respiratory pathogens.