The decision by most European Union countries to suspend the Oxford-AstraZeneca vaccine even for a limited number of days is likely to "kill a lot of people" who would otherwise have been protected from infections.
Disease experts expressed deep concerns that the halt has done damage to the overall vaccination campaign. Political analysts feared the decision making was was less based on sound scientific reasons and more down to a political dispute in the post-Brexit era.
The European Medical Agency said Thursday the vaccine is "safe and effective," and the benefits outweigh risks that blood clots occur after administration.
All told 14 European countries suspended use of Astra shots this month over reports of blood clotting, going against advice from the EMA and the World Health Organisation. The uncertainty complicated the EU’s struggling vaccination campaign since AstraZeneca shots account for about a fifth of its supply.
While governments said they were ready to resume once they got positive EMA guidance, the question remains if the suspensions did irreparable damage to the reputation of the vaccine and if people will get the shots in sufficient numbers to curb the spread of the virus. Thousands of appointments have been canceled because of concern about health risks.
The vaccine was first suspended in Norway on Sunday after four people under 50 suffered blood clots on the brain shortly after receiving a shot. All received hospital treatment and survived.
Norway's suspension was followed by Denmark and Iceland, and then several major European countries including Germany, France and Italy. The cascading effect led to Thailand and Democratic Republic of Congo also withholding the vaccine.
With millions of Europeans yet to be vaccinated, the number of Covid-19 cases are increasing with new variants of the disease taking grip and leading to a significant rise in infections.
“It's obviously the case that pausing the vaccination is going to kill a lot of people,” said Dr Ilan Kelman, professor of disasters and health at University College London.
"Right now there is no evidence of a link to blood clots but no evidence does not mean something may change in the future and the politicians have to make a decision."
Germany’s health minister said the decision to suspend AstraZeneca shots was taken on the advice of the country’s vaccine regulator, the Paul Ehrlich Institute, which called for further investigation into seven cases of clots in the brains of people who had been vaccinated.
“This decision is a purely precautionary measure,” the minister, Jens Spahn, said on announcing the suspension.
Leading British medical figures are confounded that Europe’s leaders have been so guided by precautionary principles.
“We are in the middle of a pandemic that we will not get out of it until everyone has been vaccinated,” said Prof Jeremy Brown, a key British government vaccine adviser.
“To interrupt the vaccine programme for what will most likely prove to be a spurious reason seems unnecessary.”
European-based experts say the decision-making is grounded in long-term considerations. By suspending the AstraZeneca vaccination the authorities have demonstrated the blood clotting was not ignored.
“Social media can amplify and make a real mess of things as people have issues with trusting information,” said Dr Gianluca Pescaroli, who is a University of London lecturer in disaster reduction currently based in northern Italy.
“If the issue over blood clots only came out in three months, people would say that this was information we needed now. It’s difficult but this precautionary process needs to be completed.”
The bigger picture is that anger is growing across the bloc at the slow pace of the vaccines' administration.
"Europeans are literally dying because they've got a third wave of Covid, they don't have enough vaccines because of their production troubles and now this," said Dr Alan Mendoza of the Henry Jackson Society London think tank.
The continuing fallout with Britain over a number of issues since Brexit negotiations concluded at the end of last year, including the UK reducing its supply of drug ingredients to Europe, has not helped the atmosphere.
AstraZeneca vaccine politicisation damaging Europeans
“Do we think there would have been this reaction to the AstraZeneca vaccine if Britain were still a member of the EU?” said Dr Mendoza. “Fellow EU members would have had pressure from the EU to accept the vaccine and get on with it because it would be seen as an EU vaccine not a British vaccine.”
He said: "When people are dying, to raise unfounded medical concerns and after the EMA and WHO said it's fine, you've got to wonder what on earth is going through the minds of Europe's leaders?"
Scientists suggest there is good evidence that an over-cautious decision can have a longer-term legacy. "I understand the political decision to step back and be cautious," Dr Kelman said. "But the people who are accepting that level of caution need to understand that there's a cost to it."
An example of how information can have a dramatic effect on lives comes from Japan, which in 2013 stopped its HPV cervical cancer vaccine after anecdotal reports about its side effects. As a result an estimated 5,700 young Japanese women died from the cancer.
AstraZeneca said there were 37 reports of blood clots out of more than 17 million people vaccinated in the 27-country EU and Britain.
It will be impossible to judge how many deaths will be caused by the pause but what is clear is that Europe is in the grip of another Covid wave with only 12 per cent of its adult population vaccinated, compared with 40 per cent in Britain.
If the EMA again passes the vaccine as safe later on Thursday, some countries such as France and Italy are expected to resume using the vaccine, but others may continue the suspension having contributed to the anti-AstraZeneca narrative. If a third wave does take a deadly grip, that might change.
More than 17 million people in the EU and Britain have had the AstraZeneca inoculation with fewer than 40 cases of blood clots reported. Europe has suffered almost 900,000 deaths from Covid-19.