Increased antimicrobial resistance among nonvaccine serotypes of Streptococcus pneumoniae in the pediatric population after the introduction of 7-valent pneumococcal vaccine in the United States
Increased antimicrobial resistance among nonvaccine serotypes of Streptococcus pneumoniae in the pediatric population after the introduction of 7-valent pneumococcal vaccine in the United States
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DOI：
10.1097/01.inf.0000253059.84602.c3
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发表时间：
2007-02-01
影响因子：
3.6
通讯作者：
Pichichero, Michael
中科院分区：
文献类型：
--
作者：
Farrell, David J.;Klugman, Keith P.;Pichichero, Michael
背景：7价肺炎球菌结合疫苗(PCV7)于2000年2月引入美国。PROTEKT US研究评估了2000年至2001年(第1年，n=2033)、2002至2003年(第3年，n=1740)和2003年至2004年(第4年，n=1591)从0-14岁儿童中收集的肺炎链球菌的血清型分布、PCV7覆盖率和耐药性。结果：PCV7(疫苗血清型)的分离株比例从第一年的65.5%下降到第三年的34.7%和第四年的27.0%(P<；0.0001)，地区和州一级的变化相似。第4年最常见的血清型是非疫苗血清型19A(占所有分离株的19.0%)、6A(7.8%)、3(7.6%)、15(6.3%)和35B(5.8%)以及疫苗血清型19F(12.7%)。在表达erm(B)+mef(A)大环内酯耐药基因(P<；0.0001)的分离株(P<；0.0001)中，NVS19A相对于疫苗血清19F型的增加在第1年(7.8%[19A]比86.7%[19F])到第4年(45.5%[19A]比51.7%[19F])之间增加。非血液(呼吸道)来源的NVS对青霉素(耐药：12.7-16.1%[P=0.0857]；中等敏感性：20.1-31.5%[P<；0.0001])、红霉素(21.2-31.6%[P<；0.0001])、阿莫西林-克拉维酸(1.4-5.8%[P<；0.0001])和多药耐药(耐>；=2类抗菌药物)(24.6-31.6%[P=0.0034])。结论：接种疫苗后4年，美国儿童肺炎链球菌比例大幅下降。然而，在NVS呼吸道分离株中，对常用抗菌药，包括β-内酰胺类和大环内酯类，以及多重耐药菌株的耐药性显著增加。
Background: The 7-valent pneumococcal conjugate vaccine (PCV7) was introduced in the United States in February 2000. The PROTEKT US study evaluated serotype distribution, PCV7 coverage and antimicrobial susceptibility among Streptococcus pneumoniae isolates collected from children aged 0 to 14 years in 2000 through 2001 (year 1; n = 2033), 2002 through 2003 (year 3; n = 1740) and 2003 through 2004 (year 4; n = 1591).Methods: Serotyping was performed by Neufeld Quellung reaction. Antimicrobial susceptibilities were determined centrally according to Clinical Laboratory Standards Institute methodology and interpretive breakpoints.Results: The proportion of isolates covered by PCV7 (vaccine serotypes) decreased from 65.5% (year 1) to 34.7% (year 3) and to 27.0% (year 4) (P < 0.0001) with similar changes seen at regional and state levels. The most common serotypes in year 4 were nonvaccine serotypes (NVS) 19A (19.0% of all isolates), 6A (7.8%), 3 (7.6%), 15 (6.3%) and 35B (5.8%) and vaccine serotype 19F (12.7%). NVS 19A increased relative to vaccine serotype 19F among isolates expressing the erm(B) + mef(A) macrolide-resistant genotype (P < 0.0001) between year 1 (7.8% [19A] versus 86.7% [19F]) and year 4 (45.5% [19A] versus 51.7% [19F]). Antimicrobial resistance rates (year 1 versus year 4) among NVS from nonblood (respiratory tract) sources increased for penicillin (resistant: 12.7-16.1% [P = 0.0857]; intermediate susceptibility: 20.1-31.5% [P < 0.0001]), erythromycin (21.2-31.6% [P < 0.0001]), amoxicillin-clavulanate (1.4-5.8% [P < 0.0001]) and multidrug resistance (resistance to >= 2 antimicrobial classes) (24.6-31.6% [P = 0.0034]).Conclusions: The proportion of S. pneumoniae isolates from U.S. pediatric patients covered by PCV7 decreased substantially in the 4 years after vaccine introduction. However, resistance to commonly used antimicrobials, including beta-lactams and macrolides, as well as multidrug-resistant strains increased significantly among respiratory tract isolates of NVS.