Bergman Karin, Härnqvist Tor, Backhaus Erik, Trollfors Birger, Dahl Mats S, Kolberg Helena, Ockborn Gunilla, Andersson Rune, Karlsson Johanna, Mellgren Åsa, Skovbjerg Susann
Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Department of Infectious Diseases, South Älvsborg Hospital, SE-501 82, Borås, Region Västra Götaland, Sweden.
BMC Infect Dis. 2021 Aug 4;21(1):756. doi: 10.1186/s12879-021-06430-y.
The pneumococcal conjugate vaccine PCV7 was introduced in Southwest Sweden in the child vaccination program in 2009, followed by PCV13 in 2010 and PCV10 in 2015. In this retrospective cohort study we assessed the pneumococcal serotype distribution in relation to predisposing factors, clinical manifestations and outcome during seven years after PCV introduction.
Clinical data from 1278 patients with 1304 episodes of invasive pneumococcal disease (IPD) between January 2009 and December 2015 in Region Västra Götaland, Sweden, were retrospectively collected from medical records. Pneumococcal isolates were serotyped by gel diffusion and/or Quellung reactions performed at the Public Health Agency in Sweden. Associations between serotypes and clinical characteristics were statistically evaluated by use of Fisher's exact test, Mann-Whitney U test and Logistic regression analysis, whereas IPD episodes caused by serotypes over time were analyzed by Mantel-Haenszel chi-square test.
With the exception of serotype 3, the prevalence of PCV13 serotypes decreased during the study period, from 76% (n = 157) of all IPD episodes in 2009 to 25% (n = 42) in 2015 (p < 0.001) while non-PCV13 serotypes increased, mainly among patients ≥65 years and in patients with predisposing factors, including cardiovascular disease, pulmonary disease and malignancy (p < 0.001 for all). Patients with predisposing factors, including those with malignancy, immune deficiency or renal disease, were more likely to have IPD caused by a serotype not included in PCV13 rather than a vaccine-included serotype. Serotype 3 was associated with intensive care unit admissions while serotype 1 and 7F caused IPD among healthier and younger patients. PCV13 serotypes were associated with invasive pneumonia, and non-PCV13 serotypes were associated with bacteremia with unknown focus and with manifestations other than pneumonia or meningitis.
Non-PCV13 serotypes caused the majority of IPD cases in Southwest Sweden, especially in patients ≥65 years and in patients with predisposing factors. Serotype 3, included in PCV13, was prevalent and often caused severe disease.
2009年，肺炎球菌结合疫苗PCV7在瑞典西南部的儿童疫苗接种计划中引入，随后在2010年引入PCV13，并于2015年引入PCV10。在这项回顾性队列研究中，我们评估了肺炎球菌血清型分布与PCV引入后七年中的诱发因素、临床表现及转归之间的关系。
回顾性收集了2009年1月至2015年12月期间瑞典西约塔兰地区1278例患者发生的1304次侵袭性肺炎球菌病（IPD）的临床资料。肺炎球菌分离株通过在瑞典公共卫生机构进行的凝胶扩散和/或荚膜肿胀反应进行血清分型。血清型与临床特征之间的关联采用Fisher精确检验、Mann-Whitney U检验和逻辑回归分析进行统计学评估，而不同时间由血清型引起的IPD发作则通过Mantel-Haenszel卡方检验进行分析。
除血清型3外，在研究期间PCV13血清型的患病率下降，从2009年所有IPD发作的76%（n = 157）降至2015年的25%（n = 42）（p < 0.001），而非PCV13血清型增加，主要在≥65岁的患者以及有诱发因素的患者中，包括心血管疾病、肺部疾病和恶性肿瘤患者（所有p < 0.001）。有诱发因素的患者，包括患有恶性肿瘤、免疫缺陷或肾脏疾病的患者，更有可能发生由PCV13未包含的血清型而非疫苗包含的血清型引起的IPD。血清型3与重症监护病房入院相关，而血清型1和7F在更健康、更年轻的患者中引起IPD。PCV13血清型与侵袭性肺炎相关，非PCV13血清型与病灶不明的菌血症以及肺炎或脑膜炎以外的表现相关。
在瑞典西南部，非PCV13血清型导致了大多数IPD病例，尤其是在≥65岁的患者以及有诱发因素的患者中。PCV13中包含的血清型3很常见，且常导致严重疾病。
