Institute of Biomedicine, Department of Microbiology, Virology and Immunology, University of Turku, Turku, Finland.
Department of Pediatrics and Adolescent Medicine, Turku University Hospital, Turku, Finland.
Euro Surveill. 2019 Feb;24(7). doi: 10.2807/1560-7917.ES.2019.24.7.1700832.
IntroductionPertussis outbreaks have occurred in several industrialised countries using acellular pertussis vaccines (ACVs) since the 1990s. High prevalence of pertactin (PRN)-deficient isolates has been found in these countries.AimsTo evaluate in Europe: (i) whether proportions of PRN-deficient strains increased in consecutive collections of clinical isolates; (ii) if the frequency of PRN-deficient strains in countries correlated with the time since ACV introduction; (iii) the presence of pertussis toxin (PT)-, filamentous haemagglutinin (FHA)- or fimbriae (Fim)-deficient isolates.Methods clinical isolates were obtained from different European countries during four periods (EUpert I-IV studies): 1998 to 2001 (n = 102), 2004 to 2005 (n = 154), 2007 to 2009 (n = 140) and 2012 to 2015 (n = 265). The isolates' selection criteria remained unchanged in all periods. PRN, PT, FHA and Fim2 and Fim3 expression were assessed by ELISA.ResultsIn each period 1.0% (1/102), 1.9% (3/154), 6.4% (9/140) and 24.9% (66/265) of isolates were PRN-deficient. In EUpert IV, PRN-deficient isolates occurred in all countries sampled and in six countries their frequency was higher than in EUpert III (for Sweden and the United Kingdom, p < 0.0001 and p = 0.0155, respectively). Sweden and Italy which used ACVs since the mid 1990s had the highest frequencies (69%; 20/29 and 55%; 11/20, respectively) while Finland, where primary immunisations with ACV containing PRN dated from 2009 had the lowest (3.6%). Throughout the study, no PT- or FHA-deficient isolate and one Fim2/3-deficient was detected.ConclusionResults suggest that the longer the period since the introduction of ACVs containing PRN, the higher the frequency of circulating PRN-deficient isolates.
介绍
自 20 世纪 90 年代以来，在使用无细胞百日咳疫苗（ACV）的几个工业化国家中，发生了百日咳疫情。在这些国家中，发现了大量缺乏 pertactin（PRN）的分离株。
目的
（i）连续采集临床分离株时，PRN 缺陷株的比例是否增加；（ii）PRN 缺陷株在国家的频率是否与 ACV 引入时间相关；（iii）是否存在百日咳毒素（PT）、丝状血凝素（FHA）或菌毛（Fim）缺陷分离株。
方法
在四个时期（EUpert I-IV 研究）中，从不同的欧洲国家获得了临床分离株：1998 年至 2001 年（n=102）、2004 年至 2005 年（n=154）、2007 年至 2009 年（n=140）和 2012 年至 2015 年（n=265）。所有时期的分离物选择标准均保持不变。通过 ELISA 评估 PRN、PT、FHA 和 Fim2 和 Fim3 的表达。
结果
在每个时期，1.0%（1/102）、1.9%（3/154）、6.4%（9/140）和 24.9%（66/265）的分离物为 PRN 缺陷。在 EUpert IV 中，PRN 缺陷分离株出现在所有采样国家，在六个国家中，其频率高于 EUpert III（对于瑞典和英国，p<0.0001 和 p=0.0155）。自 20 世纪 90 年代中期开始使用 ACV 的瑞典和意大利的频率最高（69%；20/29 和 55%；11/20），而芬兰首次使用含有 PRN 的 ACV 进行初级免疫的时间为 2009 年，其频率最低（3.6%）。在整个研究过程中，未检测到 PT 或 FHA 缺陷分离株，仅检测到一个 Fim2/3 缺陷分离株。
结论
结果表明，自引入含有 PRN 的 ACV 以来，时间越长，循环中 PRN 缺陷分离株的频率越高。
