Denmark has suspended the use of the Oxford-AstraZeneca COVID vaccine in a precautionary move, citing concerns that it could be linked to potentially fatal blood clots.
The Danish health authority said on Thursday it had temporarily stopped using the vaccine produced by AstraZeneca after several cases of blood clots among vaccinated people.
Iceland quickly followed Denmark by pausing vaccinations until more clarity was given on what caused the clots, the Telegraph reported.
Several countries have already halted use of one batch of the AstraZeneca jab after one person died from multiple thrombosis - clotting in the blood vessels.
The European Medicines Agency (EMA) has said there is currently no evidence that the vaccine caused the conditions.
In a tweet, Denmark's health minister Magnus Heunicke said the measure was a precaution and it was not possible to say whether there was definitely a connection between the vaccine and fatal blood clots.
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He wrote: "The health authorities have, due to precautionary measures, suspended vaccination with AstraZeneca following a signal of a possible serious side effect in the form of fatal blood clots.
"It is currently not possible to conclude whether there is a connection. We act early, it needs to be thoroughly investigated."
Austria’s national medicines regulator has suspended use of a batch of the AstraZeneca vaccine after four patients were diagnosed with dangerous blood clotting conditions after receiving their jab.
The EMA has confirmed the death of one person from multiple thrombosis 10 days after their vaccine.
A second patient was diagnosed with pulmonary embolism – where blockages form in the arteries in the lungs – but is now recovering.
As of Tuesday, two other clotting conditions had been identified in patients that had received a dose from the same batch.
The EMA said there is currently no evidence that the vaccine caused the conditions, and that thrombosis is not listed as a potential side effect of the vaccine.
It said that the batch labelled ABV5300 comprised one million doses and had been delivered to 17 EU countries.
Four other countries – Estonia, Lithuania, Luxembourg, Latvia – have suspended its use to allow time for the EMA’s Pharmacovigilance Risk Assessment Committee (PRAC) to conduct an investigation.
The EMA said: “Although a quality defect is considered unlikely at this stage, the batch quality is being investigated.”
It said PRAC was investigating the thrombosis conditions linked to the same batch as well as all other reports of thrombosis and related blood clotting conditions reported post-vaccination.
“The information available so far indicates that the number of thromboembolic events in vaccinated people is no higher than that seen in the general population,” it said.
The EMA said as of Tuesday, there had been 22 reports of such conditions among the three million people to receive the AstraZeneca jab in the European Economic Area.
Professor Stephen Evans, professor of pharmacoepidemiology at the London School of Hygiene & Tropical Medicine, said: “This is a super-cautious approach based on some isolated reports in Europe. The problem with spontaneous reports of suspected adverse reactions to a vaccine are the enormous difficulty of distinguishing a causal effect from a coincidence.
“This is especially true when we know that COVID-19 disease is very strongly associated with blood clotting and there have been hundreds if not many thousands of deaths caused by blood clotting as a result of COVID-19 disease.
"The first thing to do is to be absolutely certain that the clots did not have some other cause, including COVID-19."
He added: "The risk and benefit balance is still very much in favour of the vaccine in my view. If however, there is no shortage whatsoever of alternative vaccines, then an extreme precautionary approach as taken in Denmark may be justified."
According to the Guardian, Veronica Arthurson, head of drug safety at the Swedish Medical Products Agency, told Newsagency TT: “We do not think that there is sufficient evidence to stop vaccination with AstraZeneca’s vaccine."
Last month, German officials pleaded with people to accept the jab after reports emerged of thousands turning them down, leaving full vials unused.
Reports suggested that essential workers were reluctant to receive the AstraZeneca shot after some experienced strong side-effects.
The issue came after confusion over the efficacy and usefulness of the AstraZeneca vaccine in the EU leading to a misconception among some that it is somehow second-rate compared to the Pfizer and Moderna vaccines.
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