There is “no indication” that AstraZeneca’s coronavirus vaccine is the cause of blood clots reported in some recipients, the head of the European Medicines Agency has said.
The reported clots have prompted several major European countries to suspend use of the vaccine.
Emer Cooke said on Tuesday that the EMA is “firmly convinced” that the benefits of the AstraZeneca jab outweigh the risks, but a “very rigorous analysis” is ongoing.
Ms Cooke said experts are meeting this week to discuss the available information and will make a recommendation on Thursday.
With coronavirus cases rising in many places, governments are faced with the choice of pushing on with a vaccine that is known to save lives or suspend its use over reports of dangerous blood clots in a few recipients despite no evidence the jab was responsible.
Sweden has become the latest to join a swelling group of European Union nations choosing caution over speed.
Ms Cooke noted that thousands of people across the EU develop thromboses every year for a variety of reasons and there were no reports of increased blood clots in clinical studies of the AstraZeneca vaccine.
Europe has the luxury of being able to pick from several vaccine candidates — but the decision is still not an easy one on the continent, where the virus is again surging and where the vaccination campaign has repeatedly stumbled.
The choice may be even more fraught elsewhere because many countries are relying heavily on AstraZeneca, which is cheaper and easier to handle than some other jabs. The vaccine has so far played a huge role in the global Covax initiative to ensure vaccines get to poorer countries.
The difficulty of the decision was clear in Thailand, the first country outside Europe to temporarily suspend use of the AstraZeneca vaccine, only to recant on Tuesday when its prime minister received a dose.
“There are people who have concerns,” Prayuth Chan-ocha said after getting the jab. “But we must believe doctors, believe in our medical professionals.”
Many other countries in Asia have likewise shrugged off concerns, although Indonesia halted use of the vaccine this week, saying it would wait for a World Health Organisation report.
In addition to the EMA, AstraZeneca and the WHO have said there is no evidence the vaccine carries an increased risk of blood clots.
There have been 37 reports of blood clots among more than 17 million people who have received the vaccine across the EU and the UK, the company said.
“This is much lower than would be expected to occur naturally in a general population of this size and is similar across other licensed Covid-19 vaccines,” the Anglo-Swedish drug maker said.
But the number of countries in the bloc that are sticking with the jab is falling after heavyweights like Germany, Italy, France and Spain all said they were suspending it.
That left Belgium — and a handful of others such as Poland, Romania and Greece — increasingly isolated in their insistence that halting the vaccines now would cause a lot more harm than any side effects.