Hoshino Tadashi, Takeuchi Noriko, Fukasawa Chie, Hirose Shoko, Okui Hideyuki, Sato Hiroko, Sato Mari, Arimoto Yukiko, Nakano Atsuko, Ishiwada Naruhiko
Division of Infectious Diseases, Chiba Children's Hospital, Chiba, Japan.
Department of Infectious Diseases, Medical Mycology Research Center, Chiba University, Chiba, Japan.
J Infect Chemother. 2017 Feb;23(2):85-89. doi: 10.1016/j.jiac.2016.10.008. Epub 2016 Nov 23.
This study aimed to identify trends in frequency, serotype, and antimicrobial susceptibility of Streptococcus pneumoniae and Haemophilus influenzae isolated from middle ear fluid specimens of children aged≤15 years (mean, 2 years), before and after the introduction of the 7-valent pneumococcal conjugate vaccine (PCV7) and the H. influenzae type b vaccine, at a pediatric facility in Japan. Sixty-six S. pneumoniae and 88 H. influenzae strains were isolated from 820 middle ear fluid samples. Serotyping and antimicrobial susceptibility testing were performed. The study time-frame was divided into period 1 (2007-2010) and period 2 (2011-2014), according to the availability of vaccine public funding. The S. pneumoniae detection rate decreased from 9.6% in period 1-6.1% in period 2 (p = 0.042). PCV7 serotypes decreased from 56.8% to 9.1% (p = 0.0002). No significant change was observed for the 13-valent pneumococcal conjugate vaccine (PCV13) serotypes: 72.7% in period 1 and 59.1% in period 2. Penicillin-resistant strains (penicillin G-MIC ≥2 μg/mL) decreased from 25% to 4.5% (p = 0.038). Detection rates for H. influenzae did not change significantly: 10.3% in period 1 and 11.3% in period 2. Serotypes were mostly non-typeable: 97.9% in period 1 and 90.2% in period 2, and only one serotype b strain was isolated in each period. The frequency of ampicillin-resistant strains (MIC ≥4 μg/mL) did not change. These results show a preventative effect of PCV7 on otitis media due to S. pneumoniae. PCV7 was replaced with PCV13 in 2013 in Japan; therefore, a further decrease in pneumococcal otitis media is anticipated in the future.
本研究旨在确定在日本一家儿科机构中，在引入7价肺炎球菌结合疫苗（PCV7）和b型流感嗜血杆菌疫苗之前和之后，从≤15岁（平均2岁）儿童的中耳液标本中分离出的肺炎链球菌和流感嗜血杆菌的频率、血清型及抗菌药物敏感性趋势。从820份中耳液样本中分离出66株肺炎链球菌和88株流感嗜血杆菌。进行了血清分型和抗菌药物敏感性测试。根据疫苗公共资金的可用性，研究时间框架分为第1阶段（2007 - 2010年）和第2阶段（2011 - 2014年）。肺炎链球菌检出率从第1阶段的9.6%降至第2阶段的6.1%（p = 0.042）。PCV7血清型从56.8%降至9.1%（p = 0.0002）。13价肺炎球菌结合疫苗（PCV13）血清型未观察到显著变化：第1阶段为72.7%，第2阶段为59.1%。耐青霉素菌株（青霉素G - MIC≥2μg/mL）从25%降至4.5%（p = 0.038）。流感嗜血杆菌的检出率无显著变化：第1阶段为10.3%，第2阶段为11.3%。血清型大多不可分型：第1阶段为97.9%，第2阶段为90.2%，且每个阶段仅分离出1株b型血清菌株。耐氨苄西林菌株（MIC≥4μg/mL）的频率未发生变化。这些结果表明PCV7对肺炎链球菌所致中耳炎具有预防作用。2013年日本PCV7被PCV13取代；因此，预计未来肺炎球菌性中耳炎将进一步减少。
