In the U.S., optimism suddenly abounds about the end of the coronavirus pandemic as vaccines are increasingly available to more people across the country, causing new cases and deaths to plummet. In Europe, not so much. Most countries across the continent have now suspended the use of the AstraZeneca vaccine due to complications in a handful of vaccine recipients, further complicating the European Union’s already fumbling efforts to vaccinate national populations.

The biggest economies and populations across the Eurozone—Germany, France, Italy, and Spain—have now all halted the use of the British-Swedish drugmaker’s vaccine, an inoculation that Europe’s national vaccination strategies are heavily reliant upon. Concerns have been raised over instances of blood clots and abnormal bleeding, though the instances of adverse side effects still appear to be very, very low. The Euro bloc’s health regulator continues to consider the AstraZeneca vaccine safe and effective. The World Health Organization also considers the vaccine safe for use. It has not yet been approved for use in the U.S.

If you’re trying to keep up with Europe’s approach to the Astra Zeneca vaccine, hopefully this helps... pic.twitter.com/NsugaLHccj

— Ros Atkins (@BBCRosAtkins) March 16, 2021

There have been reports of deep vein thrombosis in both Great Britain—where there were 14 reported cases—and Germany, where there have been seven cases. These adverse reactions remain, however, statistically very small compared with the 17 million people so far who have been vaccinated with the AstraZeneca vaccine in Europe and the U.K. The company, WHO, and other global health observers point out that these numbers are lower than one would expect to see issues with blood clots in the general population. The state regulators say they are just showing an abundance of caution.

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The result, as you might expect, has been plummeting confidence in the vaccine on a continent that has already exhibited worrying signs of vaccine hesitancy. The skepticism is poised to make an already disjointed European rollout that much more arduous. The botched vaccine effort has contributed to specter of what now seems unthinkable in the U.S.—a third wave of coronavirus infections. Italy, a year after emerging as the first post-Wuhan epicenter of the virus, was the first European country to reimpose a full national lockdown Monday. Across Europe, cases are spiking, hospitalizations rising, and no vaccination relief in sight, once again raising the possibility of strict national lockdowns a year on.

• Europe
• Vaccines
• Coronavirus