Swedish Institute for Communicable Disease Control, SE-171 82 Solna, Sweden.
Vaccine. 2011 Apr 18;29(18):3438-42. doi: 10.1016/j.vaccine.2011.02.070. Epub 2011 Mar 9.
After introduction of a mono-component vaccine, containing only pertussis toxoid (PT), the incidence of pertussis was significantly higher in the Gothenburg area among children during the period October 1, 1997 until end of 2006 compared to the Rest of Sweden where a vaccine containing PT and two other pertussis antigens was used. To investigate a possible cause of this difference, the Bordetella pertussis populations in both regions were compared by determining the fimbrial serotype (Fim), the PFGE-type and the pertussis toxin promoter allele type (ptxP). Strains with the ptxP1 allele were successively replaced by ptxP3 strains producing more pertussis toxin. In Gothenburg compared to the Rest of Sweden, Fim3 and ptxP3 strains were observed earlier and reached higher frequencies in the studied period. Since ptxP3 strains have been shown to be more virulent, their higher prevalence may have contributed to the higher incidence of pertussis in the Gothenburg area. In addition we found a high degree of linkage between PFGE-profile and ptxP3. Our results highlight the importance of strain typing to gain insight into the mechanisms of immunity-associated selection of microbial subtypes and the causes of changes in incidences of infectious diseases.
在引入仅包含百日咳毒素（PT）的单组分疫苗后，1997 年 10 月 1 日至 2006 年底期间，哥德堡地区儿童百日咳的发病率明显高于瑞典其他地区，后者使用的疫苗含有 PT 和另外两种百日咳抗原。为了调查这种差异的可能原因，通过确定菌毛血清型（Fim）、PFGE 型和百日咳毒素启动子等位基因型（ptxP）比较了两个地区的博德特氏菌流行情况。具有 ptxP1 等位基因的菌株相继被产生更多百日咳毒素的 ptxP3 菌株取代。与瑞典其他地区相比，在研究期间，哥德堡的 Fim3 和 ptxP3 菌株更早出现且达到更高的频率。由于 ptxP3 菌株已被证明具有更高的毒力，它们的高流行率可能导致了哥德堡地区百日咳发病率的上升。此外，我们发现 PFGE 谱与 ptxP3 之间存在高度连锁。我们的研究结果强调了菌株分型的重要性，以深入了解与免疫相关的微生物亚群选择的机制以及传染病发病率变化的原因。
