Methods and analysis of the long-term follow up of the effectiveness of one whole cell and two acellular pertussis vaccines – Technical report

Since 1997, the Public Health Agency of Sweden has conducted an Enhanced pertussis surveillance (EPS) of children with pertussis in Sweden. Part of the surveillance includes clinical information and vaccination histories. In November 2021, a short article focusing on the long-term follow-up of the participants in a randomized clinical trial of one whole-cell vaccine and two acellular vaccines against pertussis was published. The whole-cell vaccine had slightly higher vaccine effectiveness against infection of pertussis but all the vaccines provided protection against disease. The difference was not of clinical relevance. The methods used in the article are described in more detail in this technical report.

Further reading

• Uppföljning av kikhosta (in Swedish)
• Article: Long-term follow-up of the effectiveness of one whole-cell and two acellular pertussis vaccines based on a randomised controlled vaccine trial in Sweden
• Editorial: We need pertussis vaccine that protects children for longer without the adverse effects of whole-cell versions

In Swedish

Sedan 1997 har Folkhälsomyndigheten systematiskt följt upp barn och ungdomar med kikhosta. I uppföljningen ingår klinisk information och vaccinationsstatus. Hösten 2021 publicerades en artikel med fokus på långtidsuppföljning av deltagare i en stor randomiserad klinisk studie av ett helcellsvaccin och två acellulära vaccin mot kikhosta. Helcellsvaccinet hade något bättre skyddseffekt mot insjuknande i kikhosta men alla tre vacciner gav skydd mot sjukdom. Skillnaden var inte av klinisk betydelse. Metoderna som användes i artikeln beskrivs i mer detalj i denna tekniska rapport.