Department of Microbiology, Hospital Universitari de Bellvitge-University of Barcelona-IDIBELL, Barcelona, Spain.
PLoS One. 2012;7(8):e43619. doi: 10.1371/journal.pone.0043619. Epub 2012 Aug 22.
Recently, the 13-valent pneumococcal conjugate vaccine (PCV13) has been recommended for adults. We analyzed the epidemiology of invasive pneumococcal disease (IPD) in older adults in Spain before PCV13 introduction.
METHODOLOGY/PRINCIPAL FINDINGS: IPD episodes, defined as clinical findings together with an invasive pneumococcal isolate, were prospectively collected from patients aged over 65 years in three hospitals in Spain from 2007 to 2009. A total of 335 IPD episodes were collected. Pneumonia was the main clinical syndrome, while chronic obstructive pulmonary disease, diabetes mellitus and cancer were the main underlying diseases. Pneumococcal isolates were serotyped and the molecular typing was performed by PFGE/MLST. PCV13 serotypes accounted for 59.3% of isolates, the most prevalent being serotypes 19A (15.1%), 3 (9.6%), 7F (7.5%), 14 (6.9%) and 1 (5.4%). The most frequent non-PCV13 serotypes were serotypes 16F (4.5%), 22F (3.6%), 24F (3.3%) and 6C (2.1%). The most common genotypes were CC230 (8.5%, serotypes 19A and 24F), CC156 (8.2%, serotypes 9V and 14), ST191 (7.9%, serotype 7F), CC260 (6.6%, serotype 3), ST306 (5.2%, serotype 1), CC30 (4.6%, serotype 16F) and ST433 (3.6%, serotype 22F). Comparing the 335 IPD isolates to 174 invasive pneumococci collected at the same hospitals in 1999-2000, PCV7 serotypes decreased (45.4% vs 18.4%,p<0.001), non-PCV7 serotypes included in PCV13 increased (26.4% vs 41.0%,p = 0.001) and two non-PCV13 serotypes increased (serotype 6C 0% vs 2.1%, p = 0.05; serotype 24F 0.6% vs 3.3%, p = 0.04,).
In our older adult population two serotypes (19A and 3) included in PCV13 accounted for about a quarter of IPD episodes in people ≥65 years. Non-PCV13 emerging serotypes should be carefully monitored in future surveillance studies.
最近，13 价肺炎球菌结合疫苗（PCV13）已被推荐用于成年人。我们分析了西班牙老年人中侵袭性肺炎球菌病（IPD）的流行情况在 PCV13 引入之前。
方法/主要发现：2007 年至 2009 年，我们在西班牙的三家医院前瞻性收集了年龄在 65 岁以上的患者的 IPD 病例，这些病例定义为临床发现并伴有侵袭性肺炎球菌分离株。共收集了 335 例 IPD 病例。肺炎是主要的临床综合征，而慢性阻塞性肺疾病、糖尿病和癌症是主要的潜在疾病。对肺炎球菌分离株进行血清分型，并通过 PFGE/MLST 进行分子分型。PCV13 血清型占分离株的 59.3%，最常见的血清型为 19A（15.1%）、3（9.6%）、7F（7.5%）、14（6.9%）和 1（5.4%）。最常见的非 PCV13 血清型为血清型 16F（4.5%）、22F（3.6%）、24F（3.3%）和 6C（2.1%）。最常见的基因型为 CC230（8.5%，血清型 19A 和 24F）、CC156（8.2%，血清型 9V 和 14）、ST191（7.9%，血清型 7F）、CC260（6.6%，血清型 3）、ST306（5.2%，血清型 1）、CC30（4.6%，血清型 16F）和 ST433（3.6%，血清型 22F）。将 335 例 IPD 分离株与 1999-2000 年在同一医院收集的 174 例侵袭性肺炎球菌进行比较，PCV7 血清型减少（45.4%对 18.4%，p<0.001），包括在 PCV13 中的非 PCV7 血清型增加（26.4%对 41.0%，p=0.001），两种非 PCV13 血清型增加（血清型 6C 0%对 2.1%，p=0.05；血清型 24F 0.6%对 3.3%，p=0.04）。
在我们的老年人群中，两种血清型（19A 和 3）被包括在 PCV13 中，占 65 岁以上人群 IPD 病例的四分之一左右。在未来的监测研究中，应仔细监测非 PCV13 新兴血清型。
