AstraZeneca’s Covid jab is NOT linked to blood clots, top scientists say

Scientists and officials in the UK have leapt to the defence of the country’s staple Covid vaccine as nations across Europe have stopped using the jab.

Health officials in Norway, Denmark, Iceland, Bulgaria and the Republic of Ireland have suspended the use of the British-made vaccine because of fears people are developing blood clots after getting it.

The European Medicines Agency opened an investigation after 30 reports of people being diagnosed with clots after the jab.

But the 30 – taken from a group of five million people – suggest only one in every 167,000 people developed the condition. And AstraZeneca’s own data from 17million vaccinations suggested it was more like one in 500,000, and the firm’s chief medical officer said rates were actually lower than in the general population.

Experts said it was ‘reckless’ to stop using the vaccine and that the risk of catching Covid-19 – which kills around one in 200 people and is significantly more likely to cause blood clots – was much higher. 

The ages of people affected by the clots are not known but a Norwegian health official, suggesting that the effects had been in under-50s, said they were ‘extremely rare’ and ‘it has not been established that these problems are due to the vaccine’.

Here, MailOnline answers your questions about the blood clot controversy:  

The AstraZeneca vaccine is one of the main jabs being used in the UK and scientists say they haven’t yet noticed an increase in the number of blood clots developing (stock image)

Professor Andrew Pollard, University of Oxford

Professor Anthony Harnden, deputy chairman of the Joint Committee on Vaccination and Immunisation

Oxford’s Professor Andrew Pollard (left) and the JCVI’s Professor Anthony Harnden (right) both said there is no evidence that the vaccine was causing blood clots, but there is evidence it is saving lives 

Should anyone in Britain who’s had the AstraZeneca vaccine be concerned?

The UK has used more doses of AstraZeneca’s Covid vaccine than anywhere else – approximately 11million – and both officials and scientists say there is no sign that it causes serious health problems.

Side effects are normal, and around 53,000 have been officially reported across the UK so far, but the vast majority are mild and short-lived, such as headaches, muscle pains or fever.

The 53,000 side effects out of 11million suggest just 0.5 per cent of people get them – one in 200. The frequency of severe side effects is much lower. But not everyone records their mild side effects.

British drugs regulator the Medicines and Healthcare products Regulatory Agency (MHRA), which approved the vaccine, insists the jab is safe and says people should continue to take it.

Vaccine safety chief Dr Phil Bryan said: ‘We are closely reviewing reports but given the large number of doses administered, and the frequency at which blood clots can occur naturally, the evidence available does not suggest the vaccine is the cause.

‘People should still go and get their Covid vaccine when asked to do so.’

The same message is being put out by the Joint Committee on Vaccination and Immunisation (JCVI), which advises the Government on its vaccine rollout.

Its deputy chairman Professor Anthony Harnden said on BBC Breakfast: ‘Safety is absolutely paramount and we monitor this data very carefully. 

‘We have to remember that there are 3,000 blood clots a month on average in the general population and because we’re immunising so many people, we are bound to see blood clots at the same time as the vaccination, and that’s not because they are due to the vaccination. That’s because they occur naturally in the population.

‘One ought to also remember that Covid causes blood clots. So, the risks of not having the Covid vaccination far outweigh the risks from the vaccinations.’

If safety issues did emerge in Britain, would appointments for second doses be cancelled?

People in the UK won’t be given a vaccine that officials and scientists don’t think is safe and the roll-out of AstraZeneca’s jab would immediately be stopped if it turned out to be dangerous.

The threshold for stopping using the vaccine isn’t clear — but most people who have had one dose would already have substantial protection against Covid.

A study found the jab offered 76 per cent protection against developing symptoms of the disease after one dose, and that protection lasted for at least 12 weeks. This suggests the vaccine is good enough to use with a single dose if the second one had to be abandoned.

It is not known how long the immunity from a single dose would last, but someone would likely be able to have a different vaccine months later if it started to wear off.

Health officials have yet to prove it is safe to mix-and-match vaccines when doses are given close together, meaning people must currently receive two doses of the same jab, but trials of this are being done and could mean that the brand or type of jab won’t matter in future.

AstraZeneca’s vaccine was only approved for use in Britain at the start of January, so second doses don’t have to be dished out yet because of the UK’s 12-week gap.

The gap was controversial in the first place because data had not showed that it was effective when doses were taken so far apart. 

But evidence has since emerged to show the UK’s gamble — which allowed the country to vaccinate millions of people — paid off and the protection actually gets stronger with a wider spacing between shots. 

COUNTRIES SUSPEND SPECIFIC VACCINE BATCHES AMID CLOTTING SCARE 

The decision by some countries to halt the vaccine came after a nurse in Austria, 49, died from a clot on Monday shortly after receiving the vaccine amid reports of similar cases across Europe, despite millions of doses being administered safely.

Austria, Estonia, Latvia, Lithuania and Luxembourg have also suspended the use of the same specific batch of vaccines given to the nurse, ABV5300, which was sent to 17 European countries and consisted of one million jabs.

Denmark, Norway and Iceland on Thursday went further, suspending the total use of AstraZeneca’s Covid-19 vaccine.

Italy’s medicine regulator banned a different batch of the jabs, ABV2856, after non-commissioned naval officer Stefano Paternò, 43, died of a cardiac arrest 24 hours after receiving a dose in Sicily, where a second man also died after receiving the jab. 

Regulators in the UK, which has used more doses of the vaccine than anywhere else, insist there is no reason to believe the Europeans’ deaths are linked to the vaccine. They say it was coincidence that those people had recently had the jab.

What is the blood clot controversy? 

Denmark, Norway, Iceland, Bulgaria and the Republic of Ireland have all paused the use of the vaccine because of concerns about blood clots.

The decisions came in the wake of an announcement that the European Medicines Agency was launching an investigation after it received 30 reports of people developing blood clots within days of having the vaccine, out of a total five million people. 

This was equal to around 0.0006 per cent of people or one in 167,000.

But the numbers suggest that 4,999,970 out of the 5m did not get blood clots – over 99.99 per cent.

The ages of the people developing the clots isn’t known, but Norwegian officials said they saw three cases in people under the age of 50. 

Although clots are very common they can be serious and even deadly, potentially triggering strokes, heart attacks or blockages in the lungs.

Fears about the clots were escalated when patients died with clot-related illnesses in Austria, Denmark and Italy.   

A 49-year-old nurse in Austria died with a clot last Monday, shortly after receiving the vaccine.

Austria, Estonia, Latvia, Lithuania and Luxembourg have suspended the use of the same specific batch of vaccines given to the nurse, ABV5300, which was sent to 17 European countries and consisted of one million jabs. 

Italy’s medicine regulator banned a different batch of the jabs, ABV2856, after non-commissioned naval officer Stefano Paternò, 43, died of a cardiac arrest 24 hours after receiving a dose in Sicily, where a second man also died after receiving the jab. 

What does AstraZeneca say about the risk of blood clots? 

In the midst of the crisis AstraZeneca put out a statement last night, March 14.

It said it has reported just 37 blood clot-related events out of 17million people who have been vaccinated so far in the UK and EU.

There have been 15 cases of deep vein thrombosis, which usually affects the legs, and 22 pulmonary embolisms, which are blood clots in the lungs.   

Chief medical officer at the pharmaceutical firm, Ann Taylor, said: ‘Around 17 million people in the EU and UK have now received our vaccine, and the number of cases of blood clots reported in this group is lower than the hundreds of cases that would be expected among the general population. 

‘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.’

What are blood clots and why should we care? 

Blood clots are lumps of solid blood that form inside veins and arteries, which they shouldn’t do.

The clotting process is normal and vital for the body to heal itself when it gets injured, such as when skin is cut and blood congeals and forms a scab.

But if this happens inside blood vessels it can lead to serious damage to the internal organs. If a clot forms on the wall of a vessel and doesn’t move it is less serious than one that moves around the body.

Clots in the arteries are generally more dangerous than clots in the veins because they can get into the brain or the lungs, causing a stroke or a pulmonary embolism, but clots in the veins may travel to the heart and trigger a heart attack.

Blood clots that travel around the body can cause damage in any organ that they lodge in, because they can block the flow of blood and starve it of oxygen.

Symptoms of blood clots include pain, tenderness and swelling. They most commonly develop in the legs and may then move to other bits of the body.

Experts say around 3,000 people develop a blood clot each month in the UK.

Covid-19 is known to cause blood clotting in almost everyone who gets seriously ill with it which suggests that, for many people, even the risk of a clot being caused by a vaccine would be smaller than the risk of catching coronavirus.    

The EU is facing vaccine chaos after AstraZeneca announced a fresh shortfall in planned shipments as five European countries claim others are signing ‘secret contracts’ to make sure they get extra jabs

What do scientists say about the blood clotting row? 

Dr Simon Clarke, a microbiologist at the University of Reading, said it was ‘reckless’ to simply stop using the vaccine.

He said in a tweet: ‘I keep hearing the phrase “abundance of caution” being used in reference to countries pausing rollout of [the Oxford vaccine] but is it really caution? 

‘Isn’t it actually reckless to expose your population to Covid-19 unnecessarily? Data needed or carry on vaccinating.’   

And Professor Pollard, who ran the clinical trials of Oxford’s vaccine, added on BBC Radio 4: ‘A lot of stuff happens to people all the time in normal times and, in the case of blood clots here in the UK, we see about 3,000 cases of blood clots happening every month.

‘So, when you then put a vaccination campaign on top of that, clearly those blood clots still happen and you’ve got to then try and separate out whether – when they occur – they are at all related to the vaccine or not.’

He said it was ‘very clearly’ shown in MHRA reports that blood clots were not happening any more often than they normally would.

Professor Pollard added: ‘It’s absolutely critical that we don’t have a problem of not vaccinating people and have the balance of a huge risk – a known risk of Covid – against what appears so far from the data that we’ve got from the regulators – no signal of a problem.’  

Professor David Spiegelhalter, a statistician at the University of Cambridge, said in a Guardian column that the links between the jabs and the blood clots could be ‘the basic and often creative urge to find patterns even where none exist’.

He said: ‘Deep vein thromboses (DVTs) happen to around one person per 1,000 each year, and probably more in the older population being vaccinated.

‘Working on the basis of these figures, out of 5 million people getting vaccinated, we would expect significantly more than 5,000 DVTs a year, or at least 100 every week. So it is not at all surprising that there have been 30 reports.’

And Professor Spiegelhalter added: ‘So far, these vaccines have shown themselves to be extraordinarily safe. 

‘In fact, it’s perhaps surprising that we haven’t heard more stories of adverse effects.’

WHAT IS A BLOOD CLOT?

The same process that heals a wound can be deadly if it occurs inside the body.

A blood clot is a clump of blood that has changed from a liquid to a gel-like or semisolid state. Clotting is a necessary process that can prevent you from losing too much blood in certain instances, such as when you’re injured or cut.

When a clot forms inside one of your veins, it won’t always dissolve on its own. This can be a very dangerous and even life-threatening situation.

An immobile blood clot generally won’t harm you, but there’s a chance that it could move and become dangerous. If a blood clot breaks free and travels through your veins to your heart and lungs, it can get stuck and prevent blood flow. This is a medical emergency.

Certain risk factors increase your chances of having a blood clot. A recent hospital stay, especially one that’s lengthy or related to a major surgery, increases your risk of a blood clot.

Common factors that can put you at a moderate risk for a blood clot include:

  • age, especially if you’re over 65 years old
  • lengthy travel, such as any trips that caused you to sit for more than four hours at a time
  • bed rest or being sedentary for long periods of time
  • obesity
  • pregnancy
  • a family history of blood clots
  • smoking
  • cancer
  • certain birth control pills

Source: Healthline