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Denmark has decided to completely stop the Oxford-AstraZeneca Covid vaccine rollout amid concerns about rare cases of blood clots, the first European country to do so fully.

The move is expected to delay Denmark’s vaccination program by several weeks.

Drug watchdog the European Medicines Agency (EMA) last week announced a possible link with clots but said the risk of dying of Covid-19 was much greater.

Several European countries had previously briefly suspended the AstraZeneca vaccine.

Most have now resumed vaccinations with AstraZeneca, but often with limits to older age groups.

On April 13, the US, Canada and the EU paused the Johnson & Johnson vaccine for similar reasons over clotting.

South Africa has also paused its use, despite the Johnson & Johnson being its preferred vaccine because of its effectiveness against the South African variant.

For both AstraZeneca and Johnson & Johnson, the blood clot side effects are extremely rare.

The EU’s vaccine rollout has been criticized by the WHO for being too slow, and there are concerns this latest delay could throw it into further turmoil.

Both vaccines work by a similar method, known as adenoviral vectors.

Danish officials said that all 2.4 million doses of the AstraZeneca vaccine would be withdrawn until further notice.

The Danish Health Authority said studies had shown a higher than expected frequency of blood clots following doses, affecting about one in 40,000 people.

It comes after two cases of thrombosis in Denmark were linked to vaccinations, AFP reported. One of the cases, in a 60-year-old woman, was fatal.

Director General Soren Brostrom said it had been a “difficult decision” but Denmark had other vaccines available and the epidemic there was currently under control.

However, the authority said it could not rule out using it again at another time.

During the press conference the head of Denmark’s Medicines Agency, Tanja Erichsen, fainted and was taken to hospital as a precaution. The agency later tweeted that she had recovered.

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Almost one million people in Denmark have been vaccinated, with approximately 150,000 of them receiving the AstraZeneca vaccine. The Pfizer/BioNTech and Moderna vaccines are also in use.

Adenoviruses are found in humans and other animals. Scientists use a modified version of one of these adenoviruses, known as a vector, to deliver important instructions to cells, according to the CDC.

They work by entering cells and using the cell’s machinery to produce a harmless piece of the virus that causes Covid-19, known as a spike protein. The cell then recognizes that the spike protein does not belong there and this triggers the immune system to fight back against what it thinks is an infection.

This process allows our bodies to learn how to protect us against Covid-19, according to the CDC.

Regulators are now investigating whether an unusual immune response to the adenovirus vaccines is causing the rare but severe incidences of blood clotting.

An official from the FDA told Reuters it was “plainly obvious” that the cases of blood clots linked to the Johnson & Johnson vaccine were “very similar” to those linked to the AstraZeneca vaccine.

The US paused rollout of the Johnson & Johnson vaccine after six women under 50 developed rare blood clots after getting the shot. In the UK 30 people had developed unusual blood clots and seven of them had died after getting the Oxford-AstraZeneca vaccine, out of a total of 18 million vaccinated.

Some European countries have limited the use of adenovirus vaccines to older people, who have been less affected by the rare blood clotting condition.

After the Danish announcement, France said it viewed the AstraZeneca vaccine as an “essential tool”.

France will also go ahead with plans to give the Johnson & Johnson vaccine to those aged over 55, the spokesman said. The country has already received 200,000 doses. Belgium will also give the doses it has received, while Greece and Italy will not.

Meanwhile the Czech Deputy PM Jan Hamacek said he had instructed the Czech ambassador in Denmark to try to buy the 2.4 million AstraZeneca vaccines doses that the Danes would no longer be using.

Jan Hamacek said he would also travel to Moscow to arrange deliveries of the Russian Sputnik V vaccine – another adenovirus vaccine – once its use is approved by the EMA.

Denmark was the first country to postpone use of the AstraZeneca vaccine in March. It was followed by numerous other European countries.

In a separate development, the European Commission said Pfizer-BioNTech would deliver an extra 50 million doses to the EU in the next few weeks.

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Image source: Wikimedia Commons

The Netherlands has become the latest country to halt use of the Oxford-AstraZeneca Covid vaccine over concerns about possible side effects.

The WHO and the European Medicines Agency (EMA) say there is no indication of a link between the vaccine and reports of blood clots.

Eight countries have so far fully suspended the AstraZeneca vaccinations.

The WHO told Reuters it was important that vaccination campaigns continued.

About 17 million people in the EU and the UK have received a dose of the vaccine, with fewer than 40 cases of blood clots reported as of last week, AstraZeneca said.

Experts say the number of blood clots reported after the vaccine were no more than those typically reported within the general population.

However, the Dutch government said its suspension, which will last until at least March 29, was a precaution.

Ireland, Denmark, Norway, Bulgaria and Iceland have paused inoculations with AstraZeneca vaccine, while the Democratic Republic of Congo and Indonesia have delayed the start of their AstraZeneca rollouts. Several European countries, including Italy and Austria, have suspended the use of certain batches of the drug as a precautionary measure.

Thailand announced that it would start using the vaccine on March 16, following a brief delay to the rollout over safety concerns.

The EMA – which is currently carrying out a review into incidents of blood clots – said the vaccine could continue to be administered.

In a statement, the Dutch government said it was acting out of precaution following reports from Denmark and Norway of possible serious side effects.

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Dutch drug watchdog Pharmacovigilance Centre Lareb later said that 10 cases of possible adverse side effects had been reported in the Netherlands, according to Reuters.

“We can’t allow any doubts about the vaccine,” Health Minister Hugo de Jonge said.

“We have to make sure everything is right, so it is wise to pause for now.”

Speaking on an early morning talk show on March 15, Hugo de Jonge said he hoped the suspension would last “no longer than a couple of weeks”, adding: “We need vaccines to be able to put this nasty period behind us.”

The government’s decision will now cause delays in the Dutch vaccination program.

The authorities had pre-ordered 12 million doses of AstraZeneca, with nearly 300,000 shots scheduled in the next two weeks.

AstraZeneca said there was no evidence of an increased risk of clotting due to the vaccine.

It said that across the EU and UK there had been 15 events of deep-vein thrombosis (DVT) – a blood clot in a vein – and 22 events of pulmonary embolism – a blood clot that has entered the lungs – reported among those vaccinated.

AstraZeneca said these figures were “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”.

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According to a Scottish research, the cheap inflatable leg wraps may save the lives of patients after a stroke.

The devices regularly squeeze the legs to keep blood flowing and prevent formation of fatal blood clots.

A trial with 2,876 patients, published in the Lancet, showed there were fewer clots with the wraps.

The UK’s Stroke Association said the results were “extremely encouraging” and had the potential to save thousands of lives.

A clot in the leg, a deep vein thrombosis, is normally associated with long flights, but is a problem for hospital patients unable to move.

Doctors at Western General Hospital and the University of Edinburgh said compression socks did not improve survival and clot-busting drugs led to other problems, including bleeding on the brain.

They tested the devices, which fit around the legs and fill with air every minute. They compress the legs and force the blood back to the heart.

They were worn for a month or until the patient recovered and was able to move again.

In the study, 8.5% of patients using the compression device developed blood clots, compared with 12.1% of patients who were treated normally.

According to a Scottish research, the cheap inflatable leg wraps may save the lives of patients after a stroke

According to a Scottish research, the cheap inflatable leg wraps may save the lives of patients after a stroke

Prof. Martin Dennis said: “At last we have a simple, safe and affordable treatment that reduces the risk of deep vein thrombosis and even appears to reduce the risk of dying after a stroke.

“We estimate that this treatment could potentially help about 60,000 stroke patients each year in the UK.

“If this number were treated, we would prevent about 3,000 developing a deep vein thrombosis and perhaps save 1,500 lives.”

He said the system should also be tested in other immobile patients, such as those with pneumonia.

Prof. Tony Rudd, who chairs the Intercollegiate Stroke Guideline Group at the Royal College of Physicians, said: “This study is a major breakthrough showing how a simple and safe treatment can save lives.

“It is one of the most important research studies to emerge from the field of stroke in recent years.”

Dr. Dale Webb, of the Stroke Association charity, said: “The results of this research are extremely encouraging and show that using a compression device on the legs of patients at risk of developing blood clots could be a more effective treatment.

“This new device has the potential to save thousands of lives and we would like to see it incorporated into national clinical guidelines.”

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According to two studies, using small nets to extract blood clots from patients’ brains may be the future of stroke care.

Clots block blood vessels, starving parts of the brain of oxygen, which leads to symptoms such as paralysis and loss of speech.

Two studies, presented in the Lancet medical journal, suggest extracting clots with nets could improve recovery.

The Stroke Association said it was very excited by the treatment’s potential.

There are already techniques for reopening blocked blood vessels in people’s brains.

Some patients will be given “clot-busting” drugs, but this needs to be in the hours just after the stroke and is not suitable for everyone.

Other techniques have been developed to extract the clot. Some procedures pass a tube up through the groin to the brain. There the wire passes through the clot, forming a coil on the far side and then pulling the clot out. However, this is far from routine practice.

Clots block blood vessels, starving parts of the brain of oxygen, which leads to symptoms such as paralysis and loss of speech

Clots block blood vessels, starving parts of the brain of oxygen, which leads to symptoms such as paralysis and loss of speech

The latest methods involve a tiny wire cage instead of a coil. This pushes the clot up against the walls of the artery and enmeshes the clot in the wires, allowing doctors to pull the clot back out of the groin.

Two similar devices were compared with the current coil methods. One trial of 113 patients showed 58% had good brain function after three months, compared with 33% of those treated with the coil method, as well as a lower death rate.

Another study in 178 patients showed almost double the chance of living independently after treatment.

One of the researchers involved, Prof. Jeffrey Saver from the University of California, Los Angeles, said these techniques would become more common, as they are more likely to clear clots than drugs.

“Clot-busting drugs only partially reopen 40% of large blocked arteries. These devices partially reopen 70-90% of large blocked arteries.

“Second, these devices can be used in patients in whom it is not safe to give ‘clot busting’ drugs, such as patients taking anticoagulant medications, patients who had recent surgery, and patients who are between 4.5 to eight hours after stroke onset.”

In the long term he can see drugs being used as a first option and then clot removal if the drugs fail or cannot be used.

Responding to the research, the Stoke Association’s Dr. Clare Walton said clot-busters did not work for all patients so new techniques could help many patients.

She added: “Clot retrieval devices have the potential to be used with more stroke patients and are better at removing blood clots than clot-busting drugs.

“We are very excited about this potential new treatment and look forward to further developments.”

Dr. Philip Gorelick, from Michigan State University, said the studies were “major steps forward in the successful treatment of acute ischaemic stroke, and pave the way for new treatment options”.

The research was published to coincide with a European Society of Cardiology meeting in Munich.