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Germany, France, Italy, and Spain resumed use of the Oxford-AstraZeneca COVID-19 vaccine on Thursday, hours after the European Union's drug regulator, the European Medicines Agency, said a review of the data confirmed that the vaccine is safe and effective. Norway is awaiting further research. The EMA said it found no increased risk of blood clots from AstraZeneca's vaccine, though a warning label will be affixed advising doctors and other medical experts to watch out for a rare form of clotting and bleeding in the brain.

Even if a link emerged between cerebral venous thrombosis and the vaccine, the EMA said, AstraZeneca's shots will prevent much more illness and death than they could cause. Europe is buckling under another wave of COVID-19 infections and deaths, and the World Health Organization says it isn't vaccinating its population quickly enough to slow transmission.

The decision by several European countries to pause use of the AstraZeneca vaccine not only hindered the EU's vaccination effort, it might also have irrevocably damaged trust in that vaccine — which, like all the others approved for use, has proved incredibly effective at preventing serious illness and death from COVID-19. AstraZeneca's vaccine is also central to the effort to inoculate the developing world, because it is easier to store and not currently being sold at profit. Europe's pause appears to have dented confidence in the vaccine in those countries, too.