社区获得性MRSA代替了传统的MRSA在医院中的流行吗？

David

Clinical Infectious Diseases 2008;46:787–794
© 2008 by the Infectious Diseases Society of America. All rights reserved.

MAJOR ARTICLE
Are Community-Associated Methicillin-Resistant Staphylococcus aureus (MRSA) Strains Replacing Traditional Nosocomial MRSA Strains?
社区获得性MRSA代替了传统的MRSA在医院中的流行吗？
Kyle J. Popovich,
Robert A. Weinstein, and
Bala Hota

Division of Infectious Disease, Department of Medicine, Rush University Medical Center, and Division of Infectious Disease, Department of Medicine, Stroger Hospital of Cook County, Chicago, Illinois

Received 18 July 2007; accepted 7 November 2007; electronically published 11 February 2008.

(See the editorial commentary by Boyce on pages 795–8)

Reprints or correspondence: Dr. Kyle Popovich, Division of Infectious Disease, Department of Medicine, Stroger Hospital of Cook County, 637 S. Wood St., Chicago, IL 60612 (kyle_popovich@rush.edu).

Background.  Recent studies have suggested that community-associated methicillin-resistant Staphylococcus aureus (MRSA) infection is encroaching on health care settings. （背景：最近的研究表明社区获得性MRSA感染正在侵入医院。）We describe the epidemiology of hospital-onset community-associated MRSA bloodstream infections using phenotypic and genotypic analysis.（我们用表型和基因型鉴别对医院发生的社区获得性MRSA血流感染的流行状况进行分析。）

Methods.  Using an update of an established rule derived from antibiotic susceptibilities, we inferred genotypes (i.e., community [CG] or hospital [HG]) for 208 MRSA isolates from hospital-onset (>72 h after hospital admission) bloodstream infections during 2000–2006. （方法：我们用改进的药敏指南,收集了208株分离自2000-2006年间入院后72小时发生的血流感染病人的社区和医院获得性MRSA基因型。）We compared demographic characteristics, risk factors, and outcomes of patients infected with CG or HG strains.（并比较了感染社区和医院获得性MRSA的人群特征，风险因素，和治疗结果。）

Results.  Total hospital-onset MRSA bloodstream infection incidence density rates for the periods January 2000–June 2003 and July 2003–December 2006 (0.215 cases per 1000 patient-days and 0.207 cases per 1000 patient-days, respectively) were stable (risk ratio, 1.0; 95% confidence interval, 0.7–1.3; , period 2 vs. period 1). （总体而言，医院发生的MRSA血流感染的患病率在2000年1月至2003年6月和2003年7月至2006年12月，两个时间段保持稳定。）However, the risk that these bloodstream infections were due to CG strains doubled (risk ratio, 1.9; 95% confidence interval, 1.2–3.1; ), whereas the risk due to HG strains decreased (risk ratio, 0.7; 95% confidence interval, 0.46–0.93; ). （然而，由社区获得性MRSA导致的血流感染风险增加一倍，由医院获得性MRSA地感染风险在下降。）After adjustment for comorbidities in multivariate analysis, no significant risk factors for or outcomes of infections due to CG versus HG strains were detected.（多因素分析修正结果后，没有发现二者有显著的风险因素和感染后果。） Patients infected with HG strains showed a trend toward later day of acquisition of a positive blood culture, and those infected with CG strains showed trend toward greater risk of intensive care unit admission.（感染医院获得性MRSA的病人显示出阳性血培养的天数更晚这一趋势，而社区获得性MRSA有更大的风险入住ICU.）

Conclusion.  Although total hospital-onset MRSA bloodstream infection rates were relatively stable during 2000–2006, CG strains were responsible for an increasing proportion of cases (from 24% to 49%), suggesting replacement of traditional hospital-associated strains.(结论：虽然总体上医院发生的MRSA在2000-2006年相对保持稳定，但社区获得性MRSA的百分比却在增加，从24%到49%，表明过去传统的医院型菌株被社区型代替。) For most risk factors and outcomes, patients infected with CG and HG strains were similar, suggesting that, thus far, CG strains are behaving like their traditional hospital-associated counterparts.（对于大多数分险因素和感染结果，二者相似，因此，社区型MRSA经常表现得像传统的医院型MRSA.）

楚楚

这是为什么呢？滥用抗菌药物，可是美国不是买抗菌药物比买枪支还难吗？难道MRSA不仅仅是医院感染的一个很重要的感染性疾病，而且已成为一种新的传染病？在社区人与人之间相互传播？