AstraZeneca’s vaccine faces thrombosis

Available in Germany, France, Italy and Spain Stop vaccination With AstraZeneca Coronavirus disease Vaccines. It was previously reported that people who received the vaccine would have rare blood clots.

These initiatives in the four largest EU countries have been suspended by several smaller member states-marking a new crisis of confidence Affordable vaccines This is seen as the best hope for accelerating COVID-19 vaccination throughout developing countries.

Experts emphasize that there is currently no clear evidence that the vaccine has caused these reported clots, and regulatory agencies are investigating these cases.But recent worries follow Scientist’s question About how the company communicates with employees Safety and effectiveness Its vaccine. Soon, AstraZeneca is expected to release the results of a large-scale clinical trial that will determine whether the FDA authorizes the vaccine for use in the United States.

The reason for the suspension of vaccination in Europe is that there are reports that in 20 Norway, with Another death in Denmark. in a statement In the news released on March 11, the European Medicines Agency-the equivalent of the European Union’s FDA regulatory agency-stated that among the 5 million people who received AstraZeneca injections, there were 30 cases of “thromboembolic events” or thrombus. In the European Union.

EMA stated: “There is currently no indication that vaccination will cause these conditions, and these conditions are not listed as side effects of the 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 used. “

AstraZeneca said that a total of 37 cases of pulmonary embolism and deep vein thrombosis have been reported, both of which are caused by blood clotting, which is lower than the expected incidence of the general population.

“Now about 17 million people in the European Union and the United Kingdom have been vaccinated with our vaccine, and the number of thrombosis cases reported by this group is lower than the hundreds expected,” said An Taylor, the company’s chief medical officer.A kind statement Released on March 14.

And the World Health Organization is Urge countries to continue to use vaccines, Echo has no evidence that it can cause blood clots. WHO experts will meet on Tuesday to discuss the report on thrombosis.

However, some events stopped some countries. According to German Health Minister Jens Spahn, 7 cases of rare diseases have been reported. Cerebral Venous Sinus Thrombosis (CVST), among the 1.6 million people vaccinated with AstraZeneca in Germany. The Paul Ehrlich Institute under the German Ministry of Health said on Monday, worried According to reports, this condition is accompanied by abnormal bleeding and low platelet counts, forming clots and preventing bleeding.

The few cases seen in Germany so far are more than expected, but it may be a statistical fluke. “[T]Paul Hunter, a public health expert at the University of East Anglia, said in a comment published through the British Science Media Center that even if there is no causal relationship, the possibility of such a statistical clustering of a result is actually quite high.

EMA will meet on Tuesday to discuss concerns about blood clotting and is expected to announce its conclusions on Thursday. Considering that COVID-19 cases are rising again in several EU countries-Italy is experiencing an outbreak, the long-term interruption of vaccination will be a worrying prospect. Particularly alarming surge -Spread with more contagious mutations.

Experts contacted by BuzzFeed News stated that without knowing more patient cases, there is not enough evidence to draw a clear conclusion on whether the vaccine caused blood clotting. “We want to know the age of the cases, their previous medical history, and the conditions that may cause them to develop a blood clot or bleeding risk,” said Oli Wadney of the University of Minnesota, a pharmacist who specializes in heart health.

“It may or may not be related to the vaccine. If it is related to the vaccine and it is not available everywhere, the most likely explanation is the production batch problem,” says John Moore, a virologist at Weill Cornell School of Medicine in New York, who is engaged in vaccine development. Tell BuzzFeed News. (Some countries, Including Austria, Have Particularly stop vaccination AstraZeneca vaccine from a specific batch. )

The new concern is the latest in a series of mistakes in the COVID-19 vaccine developed by AstraZeneca at Oxford University.Back in November, AstraZeneca claimed Press release Its vaccine is 70% effective overall. If half the dose is injected in the first of two injections, its effectiveness can reach 90%.But many scientists Skeptical, Especially when pharmaceutical companies recognize that this system is Wrong dose calculation. AstraZeneca later added confusion Change interpretation For the claimed 90% efficacy, from the administration itself to the lag between two administrations.

The more severe blow occurred in February, when South African trials showed that the vaccine no effect Fight against the more contagious variants of the coronavirus spreading there. South Africa suddenly stopped using the AstraZeneca vaccine plan and switched to vaccines produced by Johnson & Johnson and Pfizer/BioNTech.

Now scientists are waiting for a result Big trial The AstraZeneca vaccine trials in the United States and other countries will be the cornerstone of the company’s application for FDA authorization to use the vaccine.But some experts doubt whether adding AstraZeneca to the vaccine library in use in the United States will create more problems, such as Anti-vaccineists may catch negative publicity Surround it to disrupt the broader vaccination campaign.

“Does it really have a niche to fill? Will it be trusted enough? Or is it just another headache?” Moore said.

Children’s Health Defense Organization, which owns Peddle misinformation with Conspiracy theory Regarding vaccines for many years, it has been highlight Several European countries have suspended the use of vaccines.

The place where vaccines can have a huge impact is in developing countries, especially in Africa, where vaccine launches are Far behindThe Biden administration is already under pressure to donate the manufactured AstraZeneca vaccine to poorer countries. New York Times report March 11. At the same time, COVAX, a cooperative organization composed of WHO, the Alliance for Epidemic Prevention Innovation and the Vaccine Alliance Gavi, aims to provide affordable vaccines to poorer countries. Dependence on the use of AstraZeneca’s vaccine Provide hundreds of millions of doses in developing countries.

“Security is our biggest concern: we know that national authorities and WHO are closely monitoring the situation, and the COVAX facility will follow their guidance and recommendations,” a Gavi spokesperson said in response to a query from BuzzFeed News. “At present, the causal relationship between vaccines and individual thromboembolic events has not been determined. Vaccines are still an important and effective public health tool in the fight against this epidemic.”