EUpertstrain 4 Study of Bordetella Pertussis Isolates
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 265
- 试验地点
- 1
- 主要终点
- Study of genetic changes in the B. pertussis genomic content measured by specific molecular methods
研究概览
简要总结
This study focus on the genetic changes of B. pertussis clinical isolates. For this panels of B. pertussis isolates has been collected during four periods in different European countries.
详细描述
B. pertussis is considered as a monomorphic pathogen. However, genetic changes have been observed in several antigens (pertussis toxin, pertactin, filamentous haemagglutinin and fimbriae) included in the current acellular pertussis vaccines between vaccine strains and circulating isolates.
To study genetic changes in the B. pertussis populations in Europe, four distinct panels have been collected: EUpert I in 1999-2001 including 102 isolates, EUpert II in 2004-2005 including 154 isolates, EUpert III in 2007-2009 including 140 isolates and EUpert IV in 2012-2015 including 265 isolates. Selection criteria have remained unchanged for all four collections, which enables the opportunity to study changes in B. pertussis populations during the last 15 years.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Retrospective
入排标准
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •B. pertussis clinical isolates should be collected from subjects from different regions and be epidemiologically unrelated.
- •An equal number of isolates from vaccinated and unvaccinated subjects should be collected. Optimally, the isolates are preferred to be selected from individuals less than 5 years of age.
- •For countries with large numbers of isolates in their collections, isolates should be randomly selected according to criteria above.
排除标准
- •There is no strict exclusion criteria for this study
结局指标
主要结局
Study of genetic changes in the B. pertussis genomic content measured by specific molecular methods
时间窗: 24 months
We studied genetic changes in the main virulence genes of B. pertussis. We genotyped pertussis toxin promoter (ptxP), pertactin (PRN), fimbriae3 (Fim3) and pertussis toxin subunit A (ptxA). Serotyping of Fimbriae (Fim), Pulsed-Field Gel Electrophoresis (PFGE) and Multiple-Locus Variable number tandem repeat Analysis (MLVA) were used for further genomic analysis.
Vaccine antigen deficient (VAD) B. pertussis clinical isolates
时间窗: 24 months
We screened a panel of 265 B. pertussis clinical isolates collected from 9 European countries. We used previously developed ELISA to measure the antigen expression of pertussis toxin (PT), filamentous haemagglutinin (FHA), pertactin (PRN) and fimbriae 2\&3 (Fim2\&3). In addition, we used sequencing to further characterize the pertactin gene of the bacteria.
Association between vaccine antigen deficient (VAD) B. pertussis clinical isolates and their association to the introduction of acellular pertussis vaccination (ACV)
时间窗: 24 months
We studied the association between the frequency of VAD B. pertussis clinical isolates and their association to the introduction of ACV. Data of vaccination schedules by country and number of VAD isolates were collected and compared.
次要结局
未报告次要终点
研究者
Qiushui He
Professor
University of Turku