Fresh health concerns over Covid-19 vaccines cast doubts in Europe

Revelations that both the AstraZeneca and Johnson & Johnson coronavirus vaccines may, in extremely rare circumstances, cause blood clots have dealt a fresh blow to Europe’s already beleaguered vaccination push.

The troubles cast a cloud over the E.U.’s vaccine rollout just as it has finally begun to gain momentum after months of supply shortages and logistical problems. They risk further eroding Europeans’ willingness to be vaccinated.

On Tuesday, Johnson & Johnson said it would pause the rollout of its vaccine in Europe and the United States over those concerns.

Separately, some European countries have restricted use of the AstraZeneca vaccine for younger people, while other nations, like Norway and Denmark, are not administering it at all.

European officials intend to have fully inoculated 70 percent of the E.U.’s adult population — about 255 million people — by the end of the summer. These latest problems may jeopardize this goal.

Six recipients of the Johnson & Johnson vaccine in the U.S., out of nearly seven million, developed the disorder within about two weeks of inoculation.

Many common drugs and activities have a far higher risk of resulting in blood clots — among them, taking the contraceptive pill, flying and contracting Covid-19 itself.

Meanwhile, Chancellor Angela Merkel of Germany is moving to create a nationwide lockdown system in Germany. At current infection levels, the system could lock down more than half the country.

The World Health Organization called on governments to suspend the sale of live wild mammals in food markets to help prevent the emergence of new diseases.

India is fast-tracking vaccines approved in other countries in order to combat a Covid outbreak that is currently the world’s biggest.