The head of the EU’s illness management company warned on Friday that the novel Coronavirus could last indefinitely even as global infections slowed by nearly half in the last month and vaccine rollouts gathered pace in parts of the world.

In an interview, ECDC chief Andrea Ammon urged European nations particularly to not drop their guard in opposition to a virus that “seems very well adapted to humans” and will require consultants to tweak vaccines over time, as is the case with the seasonal flu.