1. National Institute for Public Health and the Environment; Bilthoven, the Netherlands
2. Norwegian Institute of Public Health; Oslo, Norway
3. National Center for Epidemiology (NCE); Budapest, Hungary
4. Statens Serum Institut; Copenhagen, Denmark
5. Institute for Translational Vaccinology; Bilthoven, the Netherlands
6. Leiden Academic Center for Drug Research; University of Leiden; The Netherlands
7. Public Health England; Porton Down, England