Studies have shown that pneumococcal vaccination reduces the incidence of Streptococcus pneumoniae infections but does not change the prevalence of S. pneumoniae nasopharyngeal colonization. To comprehensively and longitudinally assess the epidemiology of S. pneumoniae after the introduction of pneumococcal vaccination, we monitored the prevalence and antimicrobial susceptibility of S. pneumoniae, irrespective of its serotypes or pathogenicity, by analyzing specimens collected from a large number of patients at Jikei University Hospitals from 2009 to 2017. A total of 5763 S. pneumoniae isolates were identified out of 375,435 specimens from various sources of patients in different age groups. The prevalence of S. pneumoniae isolated only from patients <5 years old was significantly reduced with the widespread use of pneumococcal vaccines, although this reduction differed by areas where patients resided. The incidence of pneumococcal infections, including bacteremia and otitis media, clearly decreased among patients <5 years old after the introduction of pneumococcal vaccination, while the prevalence of S. pneumoniae isolated from blood specimens of patients 15–64 years old increased, suggesting the involvement of non-vaccine serotypes in the incidence of invasive pneumococcal infections. The antimicrobial susceptibility of S. pneumoniae improved after the introduction of pneumococcal vaccination. Our results show that pneumococcal vaccination has a suppressive effect on the prevalence of S. pneumoniae and the incidence of pneumococcal infections, at least for children <5 years old, in association with an improvement in the antimicrobial susceptibility of S. pneumoniae. However, further measures will be needed to control invasive pneumococcal infections caused by non-vaccine serotypes.

研究表明，肺炎球菌疫苗接种可以降低肺炎链球菌感染的发生率，但不会改变肺炎链球菌鼻咽菌落定植的发生率。为了对引入肺炎球菌疫苗后的肺炎链球菌的流行病学进行全面和纵向的评估，我们通过分析从Jikei大学大量患者身上收集的标本，监测了肺炎链球菌的流行性和耐药性，而不论其血清型或致病性从2009年到2017年的医院。共有5763肺炎链球菌从不同年龄组的各种患者来源的375,435个标本中鉴定出分离株。通过广泛使用肺炎球菌疫苗，仅从＜5岁患者中分离出的肺炎链球菌感染率显着降低，尽管这种降低因患者居住地区而异。引入肺炎球菌疫苗接种后＜5岁的患者中，包括菌血症和中耳炎在内的肺炎球菌感染的发生率明显降低，而从15-64岁患者的血液样本中分离出的肺炎链球菌感染率上升，表明参与非疫苗血清型在侵袭性肺炎球菌感染中的发生率。肺炎链球菌的药敏性引入肺炎球菌疫苗后有所改善。我们的研究结果表明，接种肺炎球菌疫苗对的患病率抑制作用肺炎链球菌在的抗菌药物敏感性的提高和肺炎球菌感染的发生率，至少为儿童<5岁，在协会肺炎链球菌。但是，将需要采取进一步措施来控制由非疫苗血清型引起的侵袭性肺炎球菌感染。