The Netherlands started vaccinating people against the coronavirus SARS-CoV-2 in January 2021. In the upcoming months, new groups of people will gradually be invited to be vaccinated. It is important to know whether people develop effective immunity to the virus after vaccination. To learn more, we are compiling information on how well people are protected against the virus. This is being investigated by RIVM.

To research this, people from different age groups are being invited to take part in the study. RIVM is starting with people aged 50 years and older who have already been taking part in the Doetinchem Study for years. This is a long-term study in which RIVM has been monitoring the health of a group of randomly selected adult Dutch citizens from Doetinchem for more than 30 years. The additional study on vaccination-based coronavirus immunity is called: Vaccinations against the Coronavirus and Immunity within the Doetinchem Study (VIDO). Participants in the Doetinchem Study who are aged 50 and over will receive an invitation to take part in the study in early March. 

The COVID-19 vaccination protects people from illness caused by the coronavirus SARS-CoV-2. However, it is still unclear how immunity is developed, how long protection lasts, and how different people of the same age will respond. RIVM is studying these questions in the VIDO Study, which is open to people who are already taking part in the Doetinchem Study because a great deal of information has already been compiled on the health of these participants over a long period of time. 

How does it work?

People who receive an invitation can register using the reply card or via the digital registration form. Then the participants receive a fingerprick self-sample set at home containing all the materials they need. They will be asked to sign a consent form, and to take a fingerprick blood sample using a self-sampling set. The questionnaire and fingerprick blood sample will take place at six different times over the course of a year. The first time is just before the participants receive their first COVID-19 vaccination. If participants have already received their first or even second vaccination, they can start later. That is not a problem.

People can participate in the study from home; unlike the Doetinchem Study, they do not have to come to the GGD location. Participation is only possible if people do in fact actually get vaccinated. Participating in the study is voluntary.

Taking part in medical research

Every research study in which participants are asked to provide samples of bodily material, such as blood, is reviewed by a Medical Research Ethics Committee (METC). This study has been reviewed and approved by METC Utrecht.

Would you like more information on participating in medical research? More information on medical research is provided on

Contact for participants

For questions about the VIDO study, please send an e-mail to