The link between the AstraZeneca vaccine and blood clots: why it is safe to have the jab

Norway and Austria were the first to sound the alarm – Austria reported that a person was diagnosed with blood clots and died 10 days after they had received the vaccination. Another was hospitalised with pulmonary embolism (blockage in arteries in the lungs) after being vaccinated.

The link between the AstraZeneca vaccine and blood clots: why it is safe to have the jab

By Anne Gulland

Boris Johnson has demonstrated his trust in the AstraZeneca vaccine by getting his first dose of the jab.

It comes after a week of turmoil in Europe in which a row erupted over the safety of the Oxford vaccine.

The Prime Minister has insisted that the vaccine is safe, a view supported this week by the European Medicines Agency and the World Health Organisation.

On Friday, Britain’s vaccine tsar accused European Union leaders of being “completely irresponsible” in doubting the vaccine and thereby raising the threat of a third wave of the virus hitting Europe.

Why is there concern over the AstraZeneca vaccine?

All the major European countries suspended the use of the AstraZeneca jab after a flurry of nations announced temporary halts to their programmes last week.

Norway and Austria were the first to sound the alarm – Austria reported that a person was diagnosed with blood clots and died 10 days after they had received the vaccination. Another was hospitalised with pulmonary embolism (blockage in arteries in the lungs) after being vaccinated.

Then Denmark announced that someone had died after receiving the jab and became the first country to suspend its AstraZeneca programme.

This prompted other countries, including Norway, the Netherlands and Ireland to follow suit. Thailand also suspended its programme but has now restarted it.

Mr Macron prompted an outcry earlier this year when he claimed the jab was “quasi-ineffective” for pensioners.

In February, Mrs Merkel, 66, faced heavy criticism for refusing the AstraZeneca jab, insisting it was not recommended for people over 65.

In her first major interview, Kate Bingham, the former head of the Government’s vaccine taskforce, accused the French president and German chancellor of encouraging anti-vaxxers after both cast doubt on the efficacy of the vaccine, developed by British scientists.

Bingham’s criticism comes as France and Germany currently face a third wave of coronavirus cases.

As of March 19, just 12 per cent of the EU population has been vaccinated, while more than half of 15 million stockpiled AstraZeneca jabs remain unused.

What do the experts say about the link between the vaccine and blood clots?

Both the European Medicines Agency and the World Health Organisation have said there is no evidence there is any link between the vaccine and blood clots and have urged countries to continue using it. 

On March 18, the EMA said the AstraZeneca vaccine was “safe and effective”, paving the way for the EU to reboot its faltering rollout of the jab. 

“This is a safe and effective vaccine. Its benefits in protecting people from Covid-19, with the associated risks of death and hospitalisation, outweigh the possible risks,” Emer Cooke, the EMA executive director, said.

WHO senior director Dr Hans Kluge said the benefits of the AstraZeneca vaccine “far outweigh the risks”. 

What is the advice in the UK?

British and European regulators published safety reviews of the jab which found that those receiving it have no greater risk of blood clots than people who do not. 

Highlighting the findings from British regulators, Mr Johnson said the benefits of the AstraZeneca vaccine in preventing Covid “far outweigh any risks”, urging those eligible to get their jabs as soon as they had the chance. 

One British man has died and four more have suffered blood clotting after receiving the AstraZeneca vaccine. However, the MHRA have urged people to continue getting the vaccine, emphasising that the chance of suffering blood clotting after the jab is just one in a million.

However, in new advice from regulators, vaccinated Britons have been urged to seek medical attention if they develop a four-day headache or unexpected bruising after receiving an AstraZeneca jab.

What does AstraZeneca say?

The company has reviewed its safety data and carried out further testing but has found no links to clotting. The company’s chief medical officer Ann Taylor has said the number of cases of blood clots reported in the 17 million people across Europe who have received the vaccine is actually lower than would be expected in the general population.

She added: “The nature of the pandemic has led to increased attention in individual cases and we are going beyond the standard practices for safety monitoring of licensed medicines in reporting vaccine events, to ensure public safety.”

Should we be worried?

Out of the 17 million people across Europe who have received the vaccine there have been 15 events of deep vein thrombosis and 22 events of pulmonary embolism. 

Blood clots are a common condition, particularly among older people who are currently prioritised for vaccination. 

Given that one in 1,000 people suffer from blood clots every year, we would expect that out of the 17 million who had been vaccinated 17,000 of those would get a blood clot over the next 12 months – about 320 people every week. 

AstraZeneca has pointed out that in clinical trials there were fewer blood clots in those given the vaccine than in those who did not receive it. 

Blood clotting is a very common condition in Covid patients and it is unclear whether any of the people reported to have died or suffered blood clots actually had the disease.

Given the tiny numbers of people who have suffered blood clots and the vast numbers who have had the vaccine the link seems very tenuous.

Should we still get the AstraZeneca vaccine?

Yes – UK scientists have urged people to get the jab if they are offered it. They have pointed out that any delays to vaccine roll out far outweigh the perceived risks of blood clots. 

Adam Finn, professor of paediatrics at the University of Bristol and a member of the Joint Committee on Vaccination and Immunisation, said “real-world” evidence on the effectiveness of the AstraZeneca vaccine was now very clear.

And he added: “If clear evidence of serious or life threatening side-effects emerges that will have important consequences. However so far it hasn’t and it’s highly undesirable to disrupt a complex and urgent programme every time people develop illnesses after receiving a vaccine that may be coincidental and not causally related.”

Stephen Evans, professor of pharmacoepidemiology at the London School of Hygiene & Tropical Medicine, echoed these sentiments.

“It is entirely reasonable that detailed studies are done on the vaccines in regard to coagulation disorders, but it seems a step too far in taking precautions that would stop people getting vaccines that would prevent disease.”

Originally published at The telegraph