The moves by the EU’s four largest countries come on the heels of a temporary halt in many of the smaller member states – and represent a new crisis of confidence for Affordable vaccine It is seen as the best hope for speeding up vaccination against COVID-19 across the developing world.
Experts stress that there is still no clear evidence that the vaccine causes these clots reported, and cases are being investigated by the regulators. But recent concerns follow earlier Questions from scholars About how the company reports issues with Safety and efficacy Vaccine. This also comes shortly before AstraZeneca is expected to release the results of a large-scale clinical trial that will determine whether the FDA permits the vaccine for use in the United States.
Vaccination stopped in Europe due to reports of three hospitalizations, including the death of one patient, among the people who received the vaccine in Norway, And the Another death in Denmark. at statement Released on March 11, the European Medicines Agency – the regulator of the European Union’s equivalent to the Food and Drug Administration – said there were a total of 30 cases of “thromboembolic events,” or blood clots, out of the 5 million people who received AstraZeneca shots in the European Union.
The European Food Association said, “There is currently no indication that vaccination caused the occurrence of these cases, which were not listed among the side effects of this vaccine.” “The position of the EMA Safety Committee … is that the benefits of the vaccine continue to outweigh its risks and the vaccine can continue to be administered.”
AstraZeneca said 37 cases of pulmonary embolism and deep vein thrombosis, which are both due to thrombosis, have been reported, which is lower than would be expected in the general population.
“About 17 million people in the European Union and the United Kingdom have now received our vaccine, and the number of blood clots reported in this group is less than the hundreds of cases expected,” said Ann Taylor, the company’s chief medical officer. a statement It was released on March 14th.
And the World Health Organization Urging countries to continue using the vaccine, Echoing that there is no evidence that it causes blood clots. WHO experts will meet to discuss reports on blood clots on Tuesday.
However, there are a few incidents that brought some countries to a halt. According to German Health Minister Jens Spahn, seven rare cases have been reported. Cerebral sinus vein thrombosis (CSVT), out of 1.6 million people who were given the AstraZeneca vaccine in Germany. On Monday, the Paul Ehrlich Institute of the German Health Ministry said it was Concerned The condition has been reported along with unusual bleeding and a decreased number of platelets that form clots and prevent bleeding.
The small number of cases seen in Germany so far may be more than expected, but it could be a statistical coincidence. “[T]”The probability of such a statistical aggregation of a single outcome is actually very high even in the absence of cause and effect,” said Paul Hunter, a public health specialist at the University of East Anglia, in a comment distributed through the UK Science Media Center.
The EMA meets to discuss concerns about blood clotting on Tuesday and is expected to release its conclusions on Thursday. A prolonged halt on vaccination could be a matter of concern, given that COVID-19 cases are on the rise again in many European Union countries – as Italy is experiencing The increase is particularly worrisome With the spread of more infectious variants.
Without knowing more about the patients’ cases, there was insufficient evidence to draw clear conclusions about whether the vaccine causes thrombosis, experts contacted by BuzzFeed News said. “We want to know the age of the cases, their past medical history, and the conditions that may create a risk of stroke or bleeding,” said Orly Vardini of the University of Minnesota, a pharmacist specializing in heart health.
It may or may not be related to the vaccine. John Moore, a virologist at Weill Cornell Medical College in New York who is developing the vaccine, told BuzzFeed News: If it is related to the vaccine, and if it is not seen everywhere, the most likely explanation is problematic. Production group. (Some countries, Including Austria, You have Specifically, the vaccination stopped From certain batches of AstraZeneca vaccine.)
The new concerns are the latest in a string of stumbling blocks to the AstraZeneca COVID-19 vaccine, which was developed at the University of Oxford. Back in November, AstraZeneca claimed Press release His vaccine was 70% effective overall, and could be up to 90% effective if given half a dose for the first two injections. But many scholars They were skepticalEspecially after the drug company admitted that this regimen was the result of A. Miscalculation of doses. AstraZeneca later added to the confusion Change his interpretation The claimed efficacy is 90% of the same doses to the difference between the two doses.
An even more serious blow came in February, when trials in South Africa showed the vaccine It was not effective Against the most contagious variant of the Corona virus circulating there. South Africa has abruptly halted plans to use the AstraZeneca vaccine and switched instead to vaccines produced by Johnson & Johnson and Pfizer / BioNTech.
Now scientists are waiting for the results of a Great experience AstraZeneca vaccine, conducted in the United States and other countries, which will be the cornerstone of the company’s application to obtain the vaccine approved for use by the Food and Drug Administration. But some experts are questioning whether adding AstraZeneca to the US vaccine warehouse will create more problems, with Vaccination opponents are more likely to take advantage of negative publicity Surrounding it to undermine the broader vaccination campaign.
“Does she really have a place to fill it? Can it be trusted enough? Or would it just be another headache?” Moore said.
Advocate for Children’s Health, an organization that has Roving misinformation And the Conspiracy theories About vaccines for years, really Highlighted The news that many European countries have stopped using the vaccine.
Where a vaccine can make a big difference in the developing world, and especially in Africa, where the vaccine is being introduced Lagging behind. The Biden administration is already under pressure to donate already manufactured doses of AstraZeneca vaccine to poor countries. The New York Times reported On March 11, meanwhile, COVAX – the collaboration formed by WHO, the Coalition for Epidemic Preparedness Innovations and Gavi, the Vaccine Alliance, to provide affordable vaccines for poor countries – is The dependence on the AstraZeneca vaccine To deliver hundreds of millions of doses throughout the developing world.
A Gavi spokesperson said in response to inquiries from BuzzFeed News: “Safety is our primary concern: We know that the national authorities and the World Health Organization are closely monitoring the situation and that the COVAX facility will follow their guidance and recommendations.” “Currently, no causal relationship has been demonstrated between the vaccine and thromboembolic events in individuals, and the vaccine remains an important and effective public health tool in combating this epidemic.”