Vaccine safety: what systems are required to ensure public confidence in vaccines?

No single surveillance system is perfect, but integrating data from multiple sources can provide comprehensive and reliable signal detection

Although phase 3 pre‐licensing vaccine studies typically include tens of thousands of participants, they generally cannot detect rare adverse events following immunisation (AEFI). Further, participants in clinical trials are generally highly selected, and safety profiles may be different when programs are applied to broader populations. Robust systems for detecting AEFI (post‐marketing surveillance) are therefore essential when large scale vaccination programs are implemented.