Department of Microbiology, University of Hong Kong, Hong Kong SAR, China.
Vaccine. 2011 Apr 12;29(17):3270-5. doi: 10.1016/j.vaccine.2011.02.025. Epub 2011 Feb 23.
This study analyzed 828 isolates causing invasive pneumococcal disease (IPD) before (1995-2001, n=265) and after (2007-2009, n=563) the introduction of the 7-valent pneumococcal conjugate vaccine (PCV7) in Hong Kong. In children <5 years, serotype 14 had declined (36-15.7%, P<0.01) while 19A had increased (0-12.9%, P<0.01) in the before and after periods, respectively. In children aged <5 years, the proportion of PCV7 serotypes declined from 89.5% to 65.7% (72.8% if included cross protection against 6A) with time but that of PCV13 serotypes remained stable (91.4-93.2%). In elderly ≥65 years, 9V and 23F decreased from 3.8% to 0.3% (P=0.01) and from 18.9% to 7.4% (P <0.01), respectively while 7F increased significantly from 0% to 4.1% (P=0.04) over the same periods. Among isolates from aged <5 years, dual penicillin/erythromycin resistance increased from 44.1% to 64.2% (P=0.01). The types that often had dual penicillin/erythromycin resistance were 6B, 14, 19F, 23F, 6A and 19A. The emergence of serotype 19A was associated with expansion of sequence type 320.
这项研究分析了香港在引入 7 价肺炎球菌结合疫苗（PCV7）之前（1995-2001 年，n=265）和之后（2007-2009 年，n=563）引起侵袭性肺炎球菌病（IPD）的 828 株分离株。在 <5 岁的儿童中，血清型 14 的比例从 36-15.7%（P<0.01）下降，而 19A 的比例从 0-12.9%（P<0.01）上升。在 <5 岁的儿童中，PCV7 血清型的比例从 89.5%下降到 65.7%（如果包括对 6A 的交叉保护，则为 72.8%），但 PCV13 血清型的比例保持稳定（91.4-93.2%）。在 ≥65 岁的老年人中，9V 和 23F 从 3.8%下降到 0.3%（P=0.01）和从 18.9%下降到 7.4%（P<0.01），而 7F 在此期间从 0%显著增加到 4.1%（P=0.04）。在 <5 岁的年龄组中，青霉素/红霉素双重耐药性从 44.1%增加到 64.2%（P=0.01）。常伴有青霉素/红霉素双重耐药的血清型有 6B、14、19F、23F、6A 和 19A。血清型 19A 的出现与序列型 320 的扩张有关。
