AstraZeneca Covid vaccine suspended in some countries due to fears of blood clots

LONDON – The coronavirus vaccine developed by AstraZeneca and the University of Oxford has now been suspended in a number of countries in Europe and Asia, following reports of blood clots in some people vaccinated. Many other countries, however, have defended their use of the shot and said they will continue their respective vaccination campaigns.

Thailand on Friday became the first Asian country to end use of the vaccine for safety concerns, shortly after Denmark announced a two-week break in its nationwide rollout after reports made state of blood clots and death.

In a setback to Europe’s ailing vaccination campaign, seven other countries have also suspended use of the Oxford-AstraZeneca vaccine: Norway, Iceland, Bulgaria, Luxembourg, Estonia, Lithuania and Latvia.

Austria and Italy, meanwhile, said they would stop using certain batches of the vaccine as a precaution.

The European medicines regulator, the European Medicines Agency, said on Thursday that there was no indication that the vaccine caused blood clots, adding that it believed the benefits of the vaccine “continued to outweigh its risks.”

The EMA acknowledged that some member states have suspended the use of the Oxford-AstraZeneca vaccine, but said inoculations could continue to be administered while an investigation into blood clots cases is underway.

As of Wednesday, around 5 million people in Europe had received the Oxford-AstraZeneca vaccine. Of this figure, 30 so-called “thromboembolic events” have been reported. These cases refer to blood clots forming in the blood vessels and blocking blood flow.

AstraZeneca said the vaccine has been studied extensively in Phase 3 trials and that peer-reviewed data confirms the vaccine is “generally well tolerated”.

Thailand’s health ministry said on Friday it would temporarily postpone use of the Oxford-AstraZeneca vaccine, calling the vaccine a “good vaccine” but wants to put it on hold for safety investigations.

Kiattiphum Wongjit, permanent secretary of the Ministry of Public Health, said the Southeast Asian country was able to suspend its vaccination campaign because it had largely contained a second wave of Covid cases thanks to quarantines and checks at the borders, according to Reuters.

The country of nearly 70 million people has so far recorded around 26,600 cases and 85 deaths, according to data compiled by Johns Hopkins University.

Thailand’s decision to suspend its planned rollout of the Oxford-AstraZeneca vaccine, which was due to start on Friday, came after the Danish health authority’s decision.

“It is important to stress that we have not given up on the AstraZeneca vaccine, but are putting it on hold,” Soren Brostrom, director of the National Board of Health in Denmark, said Thursday.

“There is good evidence that the vaccine is both safe and effective. But we and the Danish Medicines Agency must react to reports of possible serious side effects, both from Denmark and other European countries. “

Many high-income countries have chosen to continue deploying the Oxford-AstraZeneca vaccine due to safety concerns.

The UK, France, Australia, Canada and Mexico are among the countries that have sought to reassure citizens of the benefits of getting vaccinated and have said they will continue their respective vaccination campaigns.

The EMA’s safety committee is looking into the matter, but said there is currently no evidence that the vaccination caused blood clots – noting that they are not listed as side effects of this vaccine.

The European medicines regulator also noted that the data available to date showed that the number of blood clots in those vaccinated was not higher than that observed in the general population.

“Reports of blood clots received so far are no greater than the number that would have occurred naturally in the vaccinated population,” said Dr Phil Bryan, head of vaccine safety at UK drug regulation. drugs and health products.

“Public safety will always come first. We are monitoring this issue closely, but the available evidence does not confirm that the vaccine is the cause. People should always go for the COVID-19 vaccine when asked. to do”. Bryan said.

Stephen Evans, professor of pharmacoepidemiology at the London School of Hygiene & Tropical Medicine, said: “The problem with spontaneous reports of suspected adverse reactions to a vaccine is the enormous difficulty in 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 that there have been hundreds, if not several thousand, deaths from blood clotting as a result of Covid disease- 19. The first thing to do is to be absolutely certain that the clots had no other cause, including Covid-19, ”Evans added.

The Oxford-AstraZeneca vaccine is a vaccine designed to prevent the coronavirus in people 18 years of age and older. It is made up of an adenovirus that has been modified to contain the gene to make a protein from SARS-CoV-2, the virus that causes Covid-19.

The most common side effects of the vaccine, which does not contain the virus and cannot cause Covid, are usually mild or moderate and improve a few days after vaccination.

Advanced clinical trials have shown that the AstraZeneca-Oxford vaccine has an average efficacy of 70% in protecting against the virus.

A more recent study by researchers at Oxford found that the Covid vaccine was 76% effective in preventing symptomatic infection for three months after a single dose, and that the rate of effectiveness actually increased with a longer interval. long between the first and second dose.

– CNBC Holly ellyatt contributed to this report.