[Objective registration and interpretation of adverse events caused by vaccines: an essential element of vaccination]

In this era of accelerated communication, information on adverse events following vaccination is spreading more rapidly and becoming accessible to more lay people than ever before. The pace of development and the introduction of new vaccines has also increased considerably in the last decade. Therefore, it is increasingly important to objectively register and interpret possible adverse events following vaccination. In the Netherlands, information on adverse events is collected through passive reporting systems. Two recent reports on adverse events have provided reassuring results, and no new types of adverse reactions were identified. Since the transition from whole-cell pertussis vaccines to acellular vaccines, children have experienced fewer adverse events. A univocal, familiar, and easily accessible system of passive reporting is required to maintain both confidence in the vaccination programme and high vaccination coverage. The current situation in which two separate organisations (the National Institute for Public Health and Environment (RIVM) and the Netherlands Pharmacovigilance Centre Lareb) are responsible for collecting and interpreting reported adverse events following vaccination is suboptimal.