Josephine van Dongen

2 Acute gastroenteritis disease burden among infants with medical risk conditions 37 In conclusion, the observed AGE incidence, severity and healthcare usage among medical risk infants confirms substantial disease burden with increased severity and healthcare usage compared to what has been observed in healthy infants. Norovirus and rotavirus are the dominant pathogens and rotavirus is most frequently severe. AGE prevention in medical risk infants should be prioritized. Acknowledgements We would like to thank the all RIVAR par ticipants and their parents or guardians, the study team, all principal investigators and research nurses of the different study sites for their contribution to this project. The RIVAR study team: Zwar t L.M.; Tims-Polderman C.; Beurden, van M.; Bont, L.J. ; Norbruis O.J.; Hemels, M.;Well, van G.T.J.;Vlieger, Arine; Sluijs, van der J.; Stas, H.G.;Tramper-Stranders, G.; Kleinlugtenbeld, E.A.; Kempen, van A.A.M.W.;Wessels, M.; Rossum, van M. ; Dassel, C.; Houten, van M.; Pajkr t, D. The RIVAR study is funded by ZonMw, Innovatiefonds Zorgverzekeraars, GlaxoSmithKline and UMC Utrecht.