Department of Bacteria, Parasites and Fungi, Statens Serum Institut, Copenhagen, Denmark.
Sci Rep. 2019 Apr 2;9(1):5481. doi: 10.1038/s41598-019-41983-8.
Since 2012, have we in Denmark observed an increase of invasive pneumococcal infections (IPD) due to Streptococcus pneumoniae serotype 24F. We here present epidemiological data on 24F IPD cases, and characterization of 48 24F clinical isolates based on clonal relationship, antimicrobial resistance (AMR) determinants and virulence factors. IPD surveillance data from (1999-2016) were used to calculate the incidence and age-distribution of serotype 24F IPD and the effect of pneumococcal conjugated vaccines (PCV). Characterization of forty-eight 24F isolates (14.7% of all 24F isolates from the period) was based on whole-genome sequencing analysis (WGS). The IPD cases of serotype 24F showed a significant increase (p < 0.05) for all age groups after the PCV-13 introduction in 2010. The majority of tested 24F isolates consisted of two MLST types, i.e. the ST72 and the ST162. Serotype 24F IPD increased in Denmark after the PCV-13 introduction in parallel with an increase of the ST162 clone. The genotypic penicillin binding protein (PBP) profile agreed with the phenotypical penicillin susceptibility. The virulence genes lytA, ply, piaA, piaB, piaC, rspB and the cpsA/wzg were detected in all 24F isolates, while the pspA and zmpC genes were absent.
自 2012 年以来，丹麦观察到由于肺炎链球菌血清型 24F 导致的侵袭性肺炎球菌感染（IPD）有所增加。我们在此介绍了 24F IPD 病例的流行病学数据，以及基于克隆关系、抗微生物药物耐药性（AMR）决定因素和毒力因子对 48 株 24F 临床分离株的特征描述。使用（1999-2016 年）的 IPD 监测数据来计算血清型 24F IPD 的发病率和年龄分布，以及肺炎球菌结合疫苗（PCV）的效果。对 48 株 24F 分离株（该时期所有 24F 分离株的 14.7%）的特征描述是基于全基因组测序分析（WGS）进行的。在 2010 年 PCV-13 引入后，24F 血清型的 IPD 病例在所有年龄组中均呈显著增加（p<0.05）。经测试的 24F 分离株大多数属于两种 MLST 类型，即 ST72 和 ST162。24F 血清型 IPD 在丹麦 PCV-13 引入后增加，与 ST162 克隆的增加平行。基因型青霉素结合蛋白（PBP）图谱与表型青霉素敏感性一致。所有 24F 分离株均检测到 lytA、ply、piaA、piaB、piaC、rspB 和 cpsA/wzg 毒力基因，而 pspA 和 zmpC 基因不存在。
