Europe’s drug regulator says the AstraZeneca vaccine is safe

The European Union’s drug regulator said Thursday that the AstraZeneca vaccine was safe and effective, a finding that officials hope will alleviate concerns about possible rare side effects involving blood clots and allow more than a dozen countries that halted its use to add it back into their arsenal against the resurgent coronavirus.

“This is a safe and effective vaccine,” said Emer Cooke, the head of the European Medicines Agency.

The leaders of the nations, mostly in Europe, that paused its use framed their decision as a move intended to reassure the public that all concerns were being treated seriously, adding that they would await guidance from the regulator. Most of the countries signalled that they were likely to restart using the vaccine once the agency issued clearance.

The rate of inoculation in Europe is too low to slow transmission of the virus there, the World Health Organization said Thursday, reporting that new infections had risen for three successive weeks and that more people in the region were dying from the disease than a year ago.

The pause in using the AstraZeneca vaccine, however brief, threatens lingering consequences both in Europe, which is struggling to contain a new wave of infection, and around the world: The shot, sold without the goal of earning a profit, is a keystone of the WHO’s effort to inoculate poor and middle-income countries.

“In extensive vaccination campaigns, it is routine for countries to signal potential adverse events following immunization,” the WHO said Wednesday. “This does not necessarily mean that the events are linked to vaccination itself, but it is good practice to investigate them. It also shows that the surveillance system works and that effective controls are in place.”

The statement was one of many aimed at calming anxious governments and their populations at a particularly precarious moment in the pandemic.

Despite their differences, all the vaccines approved by Western regulators have shown themselves to be remarkably effective at reducing severe illness and death. And although the AstraZeneca vaccine accounts for less than 20% of the hundreds of millions of doses ordered by the European Union, it was a critical part of early rollout plans.

With infections again on the rise in many European countries, the cost of delay may be measured in lives.

In just one week in January, at the height of the last wave, Europe recorded nearly 40,000 deaths.

This week, more people are on ventilators in hospitals in Poland than at any time in the pandemic, leading officials to reimpose national restrictions, starting Saturday. Italy has reimposed lockdowns in the hopes of limiting outbreaks. Across the continent, there is rising concern about the spread of variants of the virus.

Hans Kluge, the WHO’s regional director for Europe, told reporters that the continent recorded more than 1.2 million new cases last week and that more than 20,000 people a week were dying of the virus.

In Paris, the head of public hospitals in the capital region said that the situation was increasingly dire and that authorities were struggling to find enough beds in intensive care units.

“We are living through the hardest weeks now," President Emmanuel Macron of France said Wednesday. "We know it.”

The hope had been that, by this time, vaccinations would allow governments to avoid reimposing the often draconian restrictions that have been a part of life across Europe for the past year.

The suspensions of the AstraZeneca vaccine underscored how even relatively minor disruptions could have outsize impact as the global supply remains exceedingly tight.

“Demand outstrips supply to such a large degree right now, even the slightest hiccup is felt keenly,” said Andrea Taylor, assistant director at Duke University’s Global Health Innovation Center. “There is no slack in the system.”

Both vaccine makers and governments, she said, have repeatedly offered optimistic projections that do not factor in hitches in the production process.

“They seem surprised every time a production problem causes a slowdown in delivery, as though that is a wholly unexpected event.” she said. “It shouldn’t be.”

Few countries find themselves in the enviable position of the United States — which has secured more than enough doses for every person in the country and is sitting on some 30 million doses of the AstraZeneca vaccine, which has yet to be approved by the Food and Drug Administration.

Even Britain, which moved quickly to procure vaccines and has been rapidly administering doses to most people older than 50, has been forced to shift its strategy in part to deal with dips in supply.

Starting late last year, British regulators chose to allow an increased gap between the two doses of vaccine required for maximum protection: up to 12 weeks, rather than the three weeks used in clinical trials.

That has allowed Britain to give initial protection to about 25 million people. But many of those will soon need a second dose, putting pressure on the system and leading officials to warn that distribution in April will move slower.

In Europe, where countries have largely chosen to stick to the three-week double dose strategy, the AstraZeneca vaccine was already a focus of controversy, in part as a consequence of confusing initial trial results, communication blunders by the company and delays in supply.

But the arguments are also wrapped in vaccine nationalism — with AstraZeneca’s viewed by some as the “British” vaccine and the other shot to come into use quickly, from Pfizer, as the “German” vaccine.

In Britain, the shot from AstraZeneca, a British-Swedish company, is often referred to as the Oxford vaccine, after the university where researchers developed it. In Germany, the shot made by Pfizer, a U.S. company, often goes by the name BioNTech, the smaller German company whose innovative technology helped create it in record time.

That has left public health officials struggling to explain complicated science against a backdrop of political positioning — especially as leaders try to explain to an exhausted public why they cannot get shots.

The immediate challenge for leaders across Europe will be to restore faith in the AstraZeneca vaccine.

Concerns about it arose from reports of a small number of people who developed dangerous blood clots or abnormal bleeding after receiving the shot. But many experts say that it is not clear that the numbers are higher than would occur without the vaccine, and that no evidence has emerged of a causal connection.

Despite such reassurances, different reports about potential side effects were conflated and a growing number of countries halted use of the shot.

It was the decision by Germany, more than any other, that led to the cascade of large countries suspending use of the vaccine.

Germany paused vaccinations Monday on the recommendation of the Paul Ehrlich Institute, the agency in charge of vaccine safety in the country.

Klaus Cichutek, the head of the institute, said that it had acted after seven cases of cerebral venous thrombosis had occurred four to 16 days after vaccination.

An analysis by the institute suggested that only a single case would normally be expected among the 1.6 million people who received the vaccine in that time window.

The institute said that it had convened a group of experts Monday and that they had agreed unanimously that a link to the vaccine was not implausible and should be investigated.

But the suspension put the German body at odds with the WHO and with the European Medicines Agency.

The day after the halt was announced, Cooke, the head of the European regulator, said that while investigations were underway, there was no established link between vaccination and the rare condition.

“A situation like this is not unexpected,” she said. “When you vaccinate millions of people, it is inevitable that you have rare and serious incidents of illnesses that occur after vaccination.”

“Our role at the EMA is to evaluate these,” Cooke added, “so we can figure out is this a real side effect to the vaccine, or is it a coincidence.”

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