A health worker holds a box of AstraZeneneca vaccine at the Bamrasnaradura Infectious Diseases Institute in Nonthaburi province on the outskirts of Bangkok.
Chaiwat Subprasom | SOPA images | LightRocket via Getty Images
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 vaccinated people. However, many other countries have defended their use of the shot, saying they will continue their respective vaccination campaigns.
Thailand became the first Asian country to discontinue use of the shot on Friday over safety concerns, shortly after Denmark announced a two-week break from nationwide rollout following reports of blood clots and one death.
As a setback to the ailing vaccination campaign in Europe, seven other countries have also discontinued the use of the Oxford AstraZeneca shot: Norway, Iceland, Bulgaria, Luxembourg, Estonia, Lithuania and Latvia.
Austria and Italy, meanwhile, have said they will stop using certain batches of the vaccine as a precaution.
The European drug regulator, the European Medicines Agency, stressed on Thursday that there was no evidence that the injection caused blood clots, adding that it believes the benefits of the vaccine “still outweigh the risks.”
The EMA acknowledged that some Member States had discontinued use of the Oxford AstraZeneca injection, but said the vaccinations could be continued while an investigation into cases of blood clots is ongoing.
On Wednesday, about 5 million people in Europe had received the Oxford AstraZeneca vaccine. Of this number, 30 cases of so-called “thromboembolic events” have been reported. These cases refer to blood clots that form in the blood vessels and block blood flow.
AstraZeneca has said the vaccine has been extensively studied in Phase 3 studies and peer-reviewed data confirms that the injection is “generally well tolerated.”
Why are countries pausing vaccination campaigns?
The Thai Ministry of Health announced on Friday that it would temporarily delay the use of the Oxford AstraZeneca vaccine, reportedly describing the injection as a “good vaccine,” but it plans to suspend it for safety investigations.
Kiattiphum Wongjit, permanent secretary of the health ministry, said the Southeast Asian country could interrupt its vaccination campaign because it had largely brought a second wave of Covid cases under control through quarantines and border controls, Reuters said.
A press conference on temporarily halting the rollout of AstraZeneca Covid-19 vaccination in Thailand will be held in Bangkok, Thailand, March 12, 2021.
Xinhua | Rachen Sageamsak via Getty Images
According to data from Johns Hopkins University, with nearly 70 million people, the country has recorded about 26,600 cases and 85 deaths so far.
Thailand’s decision to suspend the planned rollout of the Oxford AstraZeneca vaccine, which was due to begin on Friday, came after the decision of the Danish health authority.
“It is important to emphasize that we have not abandoned the AstraZeneca vaccine, but that we are putting it on hold,” said Soren Brostrom, director of the National Board of Health in Denmark, Thursday.
“There is good evidence that the vaccine is both safe and effective. But both we and the Danish Medicines Agency must respond to reports of possible serious side effects, both from Denmark and other European countries.”
Many high-income countries have chosen to continue the introduction of the Oxford AstraZeneca vaccine due to safety concerns.
The UK, France, Australia, Canada and Mexico are among some of the countries that have tried to reassure citizens about the benefits of getting the vaccine and have said they will continue their respective vaccination campaigns.
What do the experts say?
The EMA’s safety committee is reviewing the matter but has 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 so far shows that the number of blood clots in vaccinated people is no higher than in the general population.
“The reports of blood clots received so far are no greater than the number that would have occurred naturally in the vaccinated population,” says Dr. Phil Bryan, head of vaccine safety at the UK Medicines and Healthcare Products Regulatory.
“Public safety will always come first. We are closely monitoring this issue, but the available evidence does not confirm the vaccine is the cause. is being asked, “said Bryan.
Southampton resident Peter Brownsea receives the Oxford / AstraZeneca Covid-19 vaccine from a Hampshire Fire and Rescue Service member at a temporary vaccination center set up in Basingstoke Fire Station, Hampshire, South England, while the crew receives 999 emergency calls continues to answer.
Andrew Matthews | AFP | Getty images
Stephen Evans, Professor of Pharmacoepidemiology at the London School of Hygiene & Tropical Medicine, said: “The problem with spontaneous reports of suspected adverse reactions from a vaccine is the tremendous difficulty in distinguishing a causal effect from a seizure.”
“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 many thousands of deaths from blood clotting due to Covid-19 disease. The first thing to do. is to make absolutely sure that the clots had no other cause, including Covid-19, ”added Evans.
How does the vaccine work?
The Oxford AstraZeneca vaccine is an injection designed to prevent the coronavirus in people 18 years of age and older. It consists of an adenovirus 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 injection, which do not contain the virus and cannot cause Covid, are usually mild or moderate and improve within days of vaccination.
Late stage clinical studies showed that the AstraZeneca-Oxford injection has an average efficacy of 70% in protecting against the virus.
A more recent study by Oxford researchers found that the Covid vaccine was 76% effective in preventing symptomatic infection for three months after a single dose, and that its effectiveness increased even with a longer interval between the first and second dose.
– CNBCs Holly Ellyatt contributed to this report.