The AstraZeneca-Oxford vaccine against Covid-19 has now been discontinued in at least 115 countries, and in some countries, the situation has been the same for months. But before the rare cases of blood clotting disorder – sometimes fatal – many European countries had not yet decided to reconsider the vaccine for all age groups.
Some of those countries that now have an acceptable supply of alternative vaccines are limiting their use of the AstraZeneca-Oxford vaccine to older people, while others have stopped using it altogether. Although the risk of blood clots is extremely low, lawmakers and researchers are now working hard to raise awareness of the symptoms of the disorder: symptoms such as headaches, leg swelling, and abdominal pain – especially in younger people who have been vaccinated.
In this article, we will answer some of the most common questions about the Astrazeneca-Oxford University vaccine.
What is blood clotting and how does it usually occur?
Blood clots are gelatinous and thick spots of blood that can stop the flow of this vital substance in the body. Clots form both in response to damage to the body and due to many different diseases such as cancer and genetic disorders, and even prolonged sitting and lying down. Covid-19 itself can cause many problems with blood clots. Clots in the legs sometimes travel to the lungs and, in rare cases, to the brain, where they can be very deadly.
Blood clots from the AstraZeneca-Oxford vaccine have been of great concern in that they show unusual symptoms: blockage of blood flow to important arteries in the body – especially the colors that draw blood from the brain – along with low platelet counts. Platelets are the part of the blood that plays a role in the process of clotting.
German and Norwegian researchers have found that vaccine recipients who develop coagulation disorders produce antibodies in their bodies that lead to platelet activation and blood clotting. Researchers have now even chosen a name for this unusual reaction: Vaccine-Induced Immune Thrombotic Thrombocytopenia, or VITT for short.
So far, European researchers have not been able to identify the underlying condition of those who have experienced severe blood clots, and their condition could be helped if a common denominator can be found among all of these vaccine recipients.
Some health officials say that younger people are less likely to experience blood clots. Because the same group of people are less likely to get the worst cases of Covid-19, lawmakers have said the potential vaccine for this age group should meet the highest safety standards.
What is the frequency of unusual cases in Europe?
As of April 4 this year, researchers reported 222 cases of blood clots in the UK and 30 other countries in the European Economic Area (EU plus Iceland, Norway, and Liechtenstein). They estimate that 34 million people in these countries have received the AstraZeneca and Oxford vaccines and that the problem of apparent blood clotting occurs at a rate of 1 in 100,000.
European lawmakers, meanwhile, said they had reviewed the full details of 86 blood clots as of March 22, 18 of which were fatal.
Health officials in the UK have reported relatively few cases, possibly due to the country reaching older people in the first phase of vaccination, and all reports indicate that older people are less at risk for blood clots.
But on the other hand, the same authorities have provided evidence that in almost all scenarios, the risk of needing constant care due to Quid’s disease outweighs the risk of blood clots in the arteries. The only age group in the country whose blood clotting problems can be far more serious than those of the coronavirus are people under the age of 30 who live in areas with a low incidence of Covid-19.
Finally, officials added that all age groups at high or moderate exposure to Covid were more likely to be infected with the virus than with the vaccine given to their bodies.
What measures have Britain, European countries and other nations taken?
Germany, the Netherlands, the Philippines, Portugal, and Spain have suggested that the Astrazeneca vaccine be given only to people over the age of 60. Canada and France have proposed the same figure for people over 55, Australia for people over 50, and Belgium for people over 56. Britain, which has continued to defend the Astrazeneca vaccine in its territory, recently announced that it would use alternative vaccines for people under the age of 30.
Denmark and Norway have stopped the vaccination process, and the Democratic Republic of the Congo has postponed the start of the nationwide vaccination process.
Full immunization with the Astrazeneca vaccine requires two doses, but French lawmakers have suggested that people under the age of 55 receive their second dose through another vaccine. German officials have a similar proposal for people under 60.
The AstraZeneca vaccine has not been licensed in the United States, but the company says it is now seeking legal redress through the Food and Drug Administration. The European Medicines Agency is now calling for a label to be attached to its body, saying that blood clotting disorder should be added as a side effect.
How common are blood clots?
In the United States, 300,000 to 600,000 people experience blood clots in their lungs or leg veins or other parts of their body each year. This is a statistic officially released by the US Centers for Disease Control and Prevention. According to the data, between 1,000 and 2,000 people in the United States experience blood clots every day. While millions of people are now being vaccinated every day, some cases of blood clots in the body of people receiving the vaccine will be related to the prevalence of the incident and unrelated to the vaccine.
In the UK, lawmakers say one in every 1,000 people is affected by blood clots each year. But health experts say it will be difficult to distinguish common clots from the more unusual clots seen in the small number of Astrazeneca and Oxford vaccine recipients. Meanwhile, German researchers say that the number of blood clots in the bodies of Astrazeneca and Oxford recipients is higher than the expected number of clots in people who have never been vaccinated.
What are the symptoms of doctors and vaccine recipients in case of unexpected reactions such as blood clots?
European lawmakers say vaccinators should seek medical help immediately if they develop certain symptoms, such as swelling of the feet, persistent abdominal pain, severe and persistent headaches, blurred vision, and spotting under the skin (beyond the injection site).
But the symptoms were so vague that almost immediately, the emergency department of a British hospital was filled with patients who were worried about having exactly the same blood clot problem. As a result, hospital emergency physicians are calling for a single set of guidelines on how to manage what they call mostly unnecessary hospital visits.
German researchers have begun prescribing blood tests that can diagnose the disorder and have developed a product called intravenous immunoglobulin, which is used to treat some immune disorders.
Do other vaccines cause other bleeding disorders?
Other vaccines, especially those given to children for measles, mumps, and rubella, have always temporarily reduced platelet levels, which are essential for the formation of blood clots.
Decreased platelet levels have been reported in a small number of people who have received the modern, Pfizer-Biontec and Astrazeneca vaccines. A Florida doctor suffered a brain hemorrhage after receiving the vaccine due to an irreversible reduction in platelet counts. Others have been taken to the hospital. U.S. health officials say they are investigating various cases but have not yet released the results of the study and no direct link to the vaccines has yet been found.
What was the effect of the story on Europe?
Shortly after concerns began last month, polls in Germany, France, and Spain showed that a large number of people were skeptical about the safety of the Astrazeneca and Oxford vaccines. As a result, we have seen a decrease in the number of injections: Across Europe, only 64% of the available doses of Astrazeneca vaccine have been injected into the arm of people, which is a much lower figure than other available vaccines.
But European countries have been able to compensate for the limited use of the vaccine, largely because they have purchased vaccines from other manufacturers. The European Union expects to receive another 360 million doses of coronavirus vaccines in the second half of this year, most of which are Pfizer-bionatec vaccines, expanding the scope of vaccination.
Of course, in many cases, those people on the continent who have continued to be vaccinated with the Astrazeneca and Oxford vaccines have welcomed the opportunity. Germany, for example, although it only offers the vaccine to people over the age of 60, is still vaccinating at the same rate.
