Coronavirus: Germany’s brain blood clots after AstraZeneca vaccination not seen in other nations

Germany reported far more brain blood clots after the AstraZeneca Covid vaccine than other major European countries before banning the jab for under-60s yesterday, raising questions about why there are differences between countries.

And some experts suggest the ‘play of chance’ has resulted in more cases of the blood clot being found in Germany than other nations because ‘if you look for excesses of cases in a wide range of rare conditions, you will find some’. 

Health officials in Frankfurt say the country has seen 31 cases of the condition cerebral sinus venous thrombosis (CSVT) out of 2.7million people vaccinated.

This suggests 0.0011 per cent of people who got the jab later developed the clot – around one in 90,000 people – although there is still no proof the jab causes them.

Other major European countries have seen significantly fewer CSVT cases despite vaccinating more people, prompting questions about why Germany is different.

If the same rate in Germany had appeared in the UK, which has vaccinated far more people, 150 people would have been diagnosed with it already because five times as many jabs have been used. 

But in reality only five people have been found to have it after a jab, which experts say is not more common than usual.

The European regulator the EMA also revealed this afternoon that twice as many women had received AstraZenca’s jab in Europe than men, before adding that the people normally most at risk of CSVT are females aged 35 to 45. 

Until recently, Germany had banned the AZ jab for over-60s due to initial fears about blood clots. It raises the possibility that the rates of CSVT among vaccinated people Germany can be explained by more women who are susceptible to the condition being targeted by German rollout.  

The tenuous links between the vaccine and CSVT are still mired in confusion because experts in some countries claim the condition is most common in women but all the UK’s cases have been among men, and the frequency of cases does not appear to rise in proportion as more vaccines are carried out.  

And one expert points out it is unusual that the vaccine could make one ultra-specific type of blood clot more likely but not blood clots in general. 

In the UK, there were just five cases on record after nearly 14million vaccines – if an illness was being triggered by the vaccine, experts would expect to see more of it where more vaccines are being given.

Meanwhile Spain, France and Italy have recorded, at most, one case per million patients despite using the jab on similar age groups to Germany. 

Germany last night became the latest of at least 10 countries in Europe to have put some kind of restriction on the use of AstraZenena’s jab, most of them opting to give it only to over-60s because the CSVT cases seem to be happening in younger adults.

But scientists and regulators insist there’s still no evidence the vaccine is causing blood clots or any other severe side effects and that the risk of Covid is greater.

Germany has reported significantly more cases of cerebral sinus venous thrombosis (CSVT) than other major European countries and the reasons for it are unclear. The UK has vaccinated five times as many people but seen just one sixth as many CSVT cases, while France, Italy and Spain used the AstraZeneca jab on similar age groups but also had much lower rates of CSVT. There is still no evidence the vaccine is causing the condition, experts say

At least 10 countries in Europe, joined by Germany last night, have put some kind of restriction on the use of AstraZenena's jab, mostly opting to give it only to over-60s because the CSVT cases seem to be happening in younger adults

At least 10 countries in Europe, joined by Germany last night, have put some kind of restriction on the use of AstraZenena’s jab, mostly opting to give it only to over-60s because the CSVT cases seem to be happening in younger adults

Germany has vaccinated more people against coronavirus, but not by a big enough margin to account for the difference in CSVT cases compared to France, Italy and Spain. Britain, which has vaccinated the most of all the countries, has the lowest rate of CSVT

Germany has vaccinated more people against coronavirus, but not by a big enough margin to account for the difference in CSVT cases compared to France, Italy and Spain. Britain, which has vaccinated the most of all the countries, has the lowest rate of CSVT

German officials last night told medics to stop giving the AstraZeneca jab to people under the age of 60, saying they were worried about the blood clot link.

Health minister Jens Spahn said yesterday: ‘In sum it’s about weighing the risk of a side effect that is statistically small, but needs to be taken seriously, and the risk of falling ill with corona.’

Germany is now at the forefront of the row which has pitted regulators in Europe against other global health chiefs about the safety of the vaccine.

Its rate of cerebral sinus venous thrombosis – blood clots that form in the vein leading out of the brain and can trigger strokes – is much higher than other countries’, based on data published so far. Officials claim there’s a link to the jab.

But the UK’s rate of the same condition is significantly lower even though it has done significantly more vaccinations.

Britain’s MHRA had recorded only five cases of CSVT after 13.7million vaccinations with the AstraZeneca jab by March 22 – a miniscule rate of 0.000036 per cent.

This rate is equal to fewer than one case for every two million people vaccinated.

Other comparable countries also saw rates much lower than Germany’s – in Italy just one case was recorded out of 1.1million vaccines given by March 28.

In Spain there was one case after the first million doses, the health ministry said, and in France there were two cases from 1.43million vaccinations by March 16.

One of the biggest differences in the way the vaccine has been used across Europe is between age groups.

While the UK has used AstraZeneca’s jab as a mainstay for older adults and care home residents because it is so easy to transport, Germany refused to approve its use among people over the age of 65.


March 7: Austria suspended the use of one batch of the vaccine after a woman, 49, who had been given it died of a ‘severe coagulation disorder’ and a 35-year-old developed a blood clot in her lung.

March 11: Authorities in Denmark, Norway and Iceland suspended all use of the vaccine following a 60-year-old woman in Denmark died of a blood clot after the reports emerged in Austria. Danish health minister Magnus Heunicke said: ‘It is currently not possible to conclude whether there is a link.’

March 11: European Medicines Agency’s safety committee began an investigation into the cases. It confirms 30 cases of ‘thromboembolic events’ – clots – were reported after five million vaccines in the EEA.

March 12: Thailand suspended the use of the vaccine off the back of European worries. Bulgaria also stops using it.

March 12: The European Medicines Agency, Britain’s Medicines and Healthcare products Regulatory Agency, Health Canada, the World Health Organization and AstraZeneca itself, all spoke out to defend the vaccine and say there is no proof it’s linked to blood clots. 

March 13: The Netherlands, Italy and Ireland temporarily stopped using the vaccine as fears about the cases in Austria and Denmark snowballed.

March 14: Germany and France suspended the vaccine.

March 15: Spain, Portgual and Slovenia suspended use of the jab. 

March 15: Professor Andrew Pollard, the Oxford expert who ran the clinical trials of the jab, insisted safety data are ‘reassuring’ and said ‘clearly those blood clots still happen’ as often as they would in unvaccinated people.

March 16: World Health Organization officials met to discuss the issue. European Medicines Agency is still investigating.

March 17: Scientists accuse governments of banning the jab on political grouns. AstraZeneca’s vaccine has been a flashpoint in the past.

March 18: European Medicines Agency holds a press conference on its investigation and rules that the vaccine is ‘safe and effective’. It said there wasn’t enough evidence to rule out a link to blood clots, but also not enough to prove one. On balance, it would be safer for countries to keep using the vaccine to stop Covid. The investigation would continue.

March 18: Germany, France and Italy resume use of the jab after the EMA’s conclusion. 

March 19: Finland suspends the jab after finding blood clot cases in its own population.

March 19: Bulgaria, Cyprus, Ireland, Latvia, Lithuania, Netherlands and Spain all confirm they will start using the jab again. Scandinavian countries did not follow suit and kept the ban in place.

March 22: A study is published that found public trust in the AstraZeneca vaccine collapsed in Europe at the time of the blood clot saga. A YouGov survey found more than half of people in Germany, France, Italy and Spain believed the jab was unsafe.

March 30: Germany bans the vaccine for people under the age of 60 after officials said they had found 31 cases of CSVT after 2.7million vaccinations. 

Sources: Reuters; The Telegraph 

This was the subject of a blazing argument about the jab earlier in the year and foreign governments claimed trials did not include enough elderly people to give confidence that the vaccine worked for them.

The cases of CSVT now emerging are mostly among young women, officials say.

In Germany, 29 of the 31 cases were in women aged 20 to 63 and two in men, aged 39 and 56.

All of the UK’s five cases by mid-March, however, had been among men. 

And in another blow that weakens the connection to the jab, Germany’s neighbours also refused to give the AstraZeneca vaccine to young people and have not seen the same elevated rate of CSVT cases.

France and Italy originally only approved the jab for under-65s because of the trial data, and Spain used it for under-55s. None of these countries have seen the same level of CSVT as Germany.

Germany has vaccinated more people, but not by a big enough margin to account for the difference in CSVT cases.

The UK’s MHRA regulator, the World Health Organization, and independent scientists still insist there’s no proof the jab is a direct cause of these blood clots.

Dr Simon Clarke, a microbiologist at the University of Reading, told MailOnline: ‘Whenever you do these things you need to have a reason to do them. It’s all a balance of risk. 

‘There is no evidence that there is a problem but, even if there was, then you’re reducing what, at worst, is a tiny risk and imposing a bigger one by not giving people the protection of a vaccine.

‘People still get on airplanes and we know that there is a real risk of blood clotting if you’re sat on a plane for hours, but people still do it because they want to go on holiday.

‘So if people are more concerned about blood clots than they are Covid, I’d say they have their priorities all wrong.’ 

A UK Government spokesperson said yesterday: ‘The Oxford/AstraZeneca vaccine is safe, effective and has already saved thousands of lives in this country. 

‘As the UK’s independent regulator has said, when people are called forward, they should get the jab.’

Although scientists say there isn’t any evidence that the blood clots are developing because of vaccinations, some have a theory that it is the immune reaction making it happen.

Research teams in Germany and Norway claim the blood clotting issue may be caused by the jab, in very rare cases, making the body attack its own platelets.

Platelets are tiny chunks of cells inside blood that the body uses to build clots to stop bleeding when someone is injured. But they can also make unwanted clots.   

Experts from Oslo and Greifswald University believe the jab could cause the body to produce antibodies – normally used to fight off viruses – which mistake platelets in the blood for foreign invaders and attack them.

To compensate, the body then overproduces platelets to replace those that are being attacked, causing the blood to thicken and raising the risk of clotting. 

They admitted they ‘don’t know why this is happening’.

But the researchers say the phenomenon is similar to one that can occur in heparin-induced thrombocytopenia (HIT), when sufferers take a drug called heparin.

Experts say the condition has not been proven to be caused by the jab and may simply be showing up just because millions of people are being vaccinated and reporting their health conditions.

They added that, if spotted early, it could be diagnosed with a simple blood test and quickly treated with blood-thinners.

They stressed that even if the clots do turn out to be caused by the vaccine they are still extremely rare.

And one expert said it would be strange for the vaccine to cause one very specific type of clot to be more likely but not others.

While regulators have raised alarm about cases of CSVT, most other types of blood clots, such as deep vein thrombosis, don’t seem to be any more common. 

Dr Peter English, former chairman at the British Medical Association, said: ‘There is no evidence that these cases are caused by vaccination, rather than simply associated with it, in people who would have had such conditions anyway. 

‘And it is hard to postulate a biological reason mechanism which could explain how a clotting disorder in which clots form in a particular part of the body could be more common, when clotting, in general, is not more common.’ 

He added: ‘The way to tell if cases are caused by vaccination is to look to see if there is an excess of cases in people who have been vaccinated.

‘If you look for excesses of cases in a wide range of rare conditions, you will find some, due to the play of chance. 

‘The cases are uncommon enough that the number of excess cases will be small, which can easily happen by chance; and if you look at multiple conditions, then of course one or more of them will have an excess, just by chance.’ 

Investigating whether and why cases appear to be more common among women, experts in Europe are looking to the contraceptive pill and smoking to see whether they could be linked to a higher risk of developing CSVT.  

The risk of developing any type of blood clot while taking the contraceptive pill is significantly higher than the apparent risk of being diagnosed with CSVT after a vaccine.

Around one in 1,600 women are affected each year, although it’s not clear how many of these clots affect the brain, which is a rare occurrence. 

The Pill can raise the blood clot risk because it increases oestrogen levels which also increase proteins linked to clotting, thickening the blood. 

Smoking is also known to pose a greater risk of blood clots, because it can make platelets in the veins and arteries – which trigger clots – stick together.  

These may both put people who take the Pill or smoke at a higher baseline risk of developing a blood clot, meaning it would take less of a push for one to develop.