シンポジウム 151）Epidemiology of infectious diseases and antibiotic resistance in China

Institute of Respiratory Diseases, the First Affiliated Hospital
China Medical University, Shenyang, P.R. of China○Jian Kang
Infectious diseases and the increasing threat of antibiotic resistance remain a major problem in China Today.
Community-acquired pneumonia (CAP) and Hospital-acquired pneumonia (HAP) are most common infectious diseases inChina.
A multicenter study on the pathogenic agents in 665 adult patients with CAP in China was published in Chinese journalin 2006. The results showed that pathogens were identified in 53.1% with valid serum samples and sputum cultures. The
percentage of pathogens was as follows: Mycoplasma pneumoniae (20.17%), Streptococcus pneumoniae (10.13%),
Haemophilus influenzae (9.12%), Chlamydia pneumoniae (6.16%), Klebsiella pneumoniae (6.11%), Legionella
pneumophila (5.11%), Staphylococcus aureus (3.18%), Escherichia coli (1.16%), Moraxella catarrhalis (1.13%),
Pseudomonas aeruginosa (1.10%).
A clinical survey on HAP in 16 Chinese teaching hospitals including 613 cases was performed from August of 2008 toDecember of 2010. The results showed that the pathogens of HAP were as follows: Acinetobacter Baumannii ( 29.85%),Pseudomonas aeruginosa (21.86%), Staphylococcus aureus (13.38%), Klebsiella pneumoniae (9.62%), Candida albicans(6.04%), Stenotrophomonas maltophilia (4.57%), Escherichia coli (3.26%), Enterobacter cloacae (2.12%), Coagulasenegative staphylococcus (1.79%), Candida tropicalis (1.17%).
The CHINET study is an antibiotic resistance multicenter surveillance in China. CHINET data in 2010 showed that atotal of 1961 clinical strains of Enterobacter spp. were collected. The resistance rate of Enterobacter strains was the highest
to ampicillin, cefazolin and cefoxitin (>93%), relatively higher to ceftazidime and cefotaxime (38.6% and 51.2%,respectively), and relatively lower to piperacillin-tazobactam, cefepime, cefoperazone-sulbactam, ertapenem, amikacin, orciprofloxacin (generally <20%), and the lowest to imipenem and meropenem (5.2% and 4.8, respectively). Of the 5080
clinical strains of Pseudomonas aeruginosa, 91.2% were isolated from hospitalized patients, and 69.9% were isolated fromrespiratory tract. These Pseudomonas aeruginosa isolates showed the lowest resistance rate (15.3%) to amikacin. The
percentage of the Pseudomonas aeruginosa isolates resistant to other antimicrobial agents was generally above 18%. The
5523 nonduplicate strains of Acinetobacter showed the lowest resistance rates to cefoperazone-sulbactam and minocycline(33.6% and 35.4%, respectively). About 62.1% and 63.6% of these strains were resistant to imipenem and meropenem,respectively.
A total of 5608 clinical isolates of Gram-positive bacteria were collected from 12 teaching hospitals across China from2005 to 2010. Overall, the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistantcoagulase-negative staphylococci (MRSCoN) were 46.8% and 81.5%, respectively. Isolates from inpatients exhibited ahigher rate of MRSA than that from outpatients (52.3% versus 26.2%, P < 0.001). The prevalence of MRSA in respiratory
infections (67.5%) was higher than in other sources of infections (P < 0.001).
The resistance ratio of macrolides to Mycoplasma pneumoniae is very high in China. 53 clinical isolates from children
in Shanghai City showed 83% isolates were highly resistant to erythromycin (MICs>128mg/L), azithromycin andclarithromycin. The other study containing 50 isolates from children in Beijing showed 92% isolates were resistant tomacrolides. 67 isolates from adults with CAP in Beijing showed 69% isolates were resistant to macrolides.