Ndlangisa Kedibone M, du Plessis Mignon, Wolter Nicole, de Gouveia Linda, Klugman Keith P, von Gottberg Anne
Centre for Respiratory Diseases and Meningitis (CRDM), National Institute for Communicable Diseases (NICD), a division of the National Health Laboratory Service, Johannesburg, South Africa; Respiratory and Meningeal Pathogens Research Unit, University of the Witwatersrand, Johannesburg, South Africa; Medical Research Council, Johannesburg, South Africa.
Centre for Respiratory Diseases and Meningitis (CRDM), National Institute for Communicable Diseases (NICD), a division of the National Health Laboratory Service, Johannesburg, South Africa; Medical Research Council, Johannesburg, South Africa.
PLoS One. 2014 Sep 18;9(9):e107666. doi: 10.1371/journal.pone.0107666. eCollection 2014.
We determined the sequence types of isolates that caused invasive pneumococcal disease (IPD) prior to routine use of pneumococcal conjugate vaccines (PCV) in South Africa. PCV-13 serotypes and 6C isolates collected in 2007 (1 461/2 437, 60%) from patients of all ages as part of on-going, national, laboratory-based surveillance for IPD, were selected for genetic characterization. In addition, all 134 non-PCV isolates from children <2 years were selected for characterization. Sequence type diversity by serotype and age category (children <5 years vs. individuals ≥5 years) was assessed for PCV serotypes using Simpson's index of diversity. Similar genotypes circulated among isolates from children and adults and the majority of serotypes were heterogeneous. While globally disseminated clones were common among some serotypes (e.g., serotype 1 [clonal complex (CC) 217, 98% of all serotype 1] and 14 [CC230, 43%)]), some were represented mainly by clonal complexes rarely reported elsewhere (e.g., serotype 3 [CC458, 60%] and 19A [CC2062, 83%]). In children <2 years, serotype 15B and 8 were the most common serotypes among non-PCV isolates (16% [22/134] and 15% [20/134] isolates, respectively). Sequence type 7052 and 53 were most common among serotypes 15B and 8 isolates and accounted for 58% (7/12) and 64% (9/14) of the isolates, respectively. Serotype 19F, 14, 19A and 15B had the highest proportions of penicillin non-susceptible isolates. Genotypes rarely reported in other parts of the world but common among some of our serotypes highlight the importance of our data as these genotypes may emerge post PCV introduction.
我们确定了在南非常规使用肺炎球菌结合疫苗（PCV）之前引起侵袭性肺炎球菌疾病（IPD）的分离株的序列类型。作为正在进行的全国性基于实验室的IPD监测的一部分，从各年龄段患者中收集的2007年的PCV-13血清型和6C分离株（1461/2437，60%）被选作基因特征分析。此外，还选择了所有来自2岁以下儿童的134株非PCV分离株进行特征分析。使用辛普森多样性指数评估PCV血清型按血清型和年龄类别（5岁以下儿童与≥5岁个体）的序列类型多样性。儿童和成人的分离株中存在相似的基因型，并且大多数血清型是异质的。虽然全球传播的克隆在某些血清型中很常见（例如，血清型1[克隆复合体（CC）217，占所有血清型1的98%]和14[CC230，43%]），但有些主要由其他地方很少报道的克隆复合体代表（例如，血清型3[CC458，60%]和19A[CC2062，83%]）。在2岁以下儿童中，血清型15B和8是非PCV分离株中最常见的血清型（分别占分离株的16%[22/134]和15%[20/134]）。序列类型7052和53在血清型15B和8分离株中最常见，分别占分离株的58%（7/12）和64%（9/14）。血清型19F、14、19A和15B中青霉素不敏感分离株的比例最高。在世界其他地区很少报道但在我们的某些血清型中常见的基因型凸显了我们数据的重要性，因为这些基因型可能在引入PCV后出现。
