This investigation analyses Robert Kennedy Jr’s anti-vax movement Children’s Health Defense efforts to expand its activities in Europe. Since August 2020, the US anti-vaccine group has significantly increased its presence in Europe, creating a legal structure in Belgium and organising multiple events to spread its health and anti-vax disinformation narratives all over the continent. What should be done to limit the opportunities for anti-vax groups to manipulate public discussions around vaccines in the EU and prevent them from contributing to the creation of new health crises, which put at risk the health of some communities?