[ad_1]
(CNN Spanish) – AstraZeneca’s vaccine and the University of Oxford is at the center of scrutiny after several European countries decided to discontinue use of the antigen after a small number of people who received it developed blood clots.
In this episode, Dr. Elmer Huerta analyzes the data.
You can listen to this episode on Apple Podcasts, Spotify, or your favorite podcast platform, or read the transcript below.
Hi, I’m Dr. Elmer vegetable garden And this is your daily dose of information on the new coronavirus. Information that we hope will be useful to take care of your health and that of your family.
The AstraZeneca vaccine: what happens in Europe?
As of this writing, the AstraZeneca / Oxford vaccine situation in Europe is dramatic.
Germany, France, Italy, Denmark, Norway, Iceland, Bulgaria, the Netherlands, Ireland and Spain are the countries that have decided to temporarily or indefinitely suspend their immunization programs with the Oxford and AstraZeneca vaccines.
The reason given by the different governments is that they want to clarify the relationship that could exist between the application of the vaccine and the appearance of some cases of thromboembolic phenomena in people who received it.
A thromboembolic phenomenon is what, in popular language, is called clot formation in the body. In medicine, clots that form in veins or arteries are called thrombi, and when these break off and reach organs such as the brain or lungs, they are called emboli.
Thromboembolism then means that – for various reasons – thrombi or clots form within the veins, and these are dislodged and emboli can affect various organs, potentially causing death.
According to the president of France, Emmanuel Macron, the suspension of the vaccine will be made until the results of the research being done by the European Medicines Agency or EMA, the equivalent of the Food and Drug Administration, the FDA, for its acronym. in English, from the United States.
How was the AstraZeneca and Oxford vaccine made?
Today we will remember what the Oxford and AstraZeneca vaccine consists of. We will see how the EMA will determine if there is a link between the AstraZeneca / Oxford vaccine and clot formation.
First, let’s remember that the AstraZeneca / Oxford vaccine uses a chimpanzee cold virus as a vector – a kind of Trojan horse – to introduce a gene for the new coronavirus into the vaccinated person’s body.
That gene contains the instruction manual for synthesizing the spike protein of the virus.
Upon receiving the vaccine, the person’s cells begin to manufacture the spike protein of the new coronavirus, which upon reaching the blood tricks the defense system into believing that it is being attacked by the complete virus.
This, in turn, triggers the production of neutralizing antibodies against the spike, antibodies that will defend us from a possible infection with the complete virus in the future.
The results of the study phases
The results of the phase 1 and phase 2 studies were published in August 2020 in The Lancet.
Those results determined that the vaccine was safe and effective in stimulating antibody production, and as we heard in the December 9 episode, the phase 3 study, conducted in Brazil, South Africa, and the United Kingdom, also published in The Lancet, reaffirmed that the vaccine was safe and effective in preventing symptomatic disease.
Second, and to understand how the EMA will calculate if there is a relationship between the vaccine and the formation of blood clots in the people who received it, we must understand what the incidence of a disease means in a community.
Newly diagnosed cases of a certain disease that occur or are recorded in a given community over a specified period of time are called disease incidence.
For example, in the case of thromboembolic phenomena, it is estimated that in Europe between 104 to 183 cases of clots occur regularly per 100,000 people per year.
That means, for example, that for every 100,000 people who live in a city, between 104 and 183 of them will develop a clot-forming problem at some point in the year and will go to a hospital to be treated.
There are many causes for people in a community to form blood clots on a daily basis, including inherited diseases, diseases of the veins, trauma, etc.
What do scientists say?
What the EMA epidemiologists and statisticians will now do is carefully review the statistics for each geographic region where the vaccine was given and where clots occurred. On that basis, they will calculate how many cases in excess of what is normally expected have occurred.
In other words, if in a certain region there are, say, 120 cases of clots during a year (or what is the same 10 cases per month), then the researchers will try to establish if in that region they occurred, for example, 15 or 16 in the last month, that is, an excess of five to six cases over what would normally be expected.
If that happened, the researchers might suggest that the vaccine had something to do with the clots.
In contrast, if the statisticians calculate that in that region in which the vaccine was administered and the clots appeared, only 8 clots occurred per month, that is, two less than would normally be expected, then they may decide that the cases of thromboembolism would not be related to the vaccine.
Obviously, in addition to these important statistical analyzes, the researchers will analyze the medical records of each case, to determine what other factors could have contributed to the formation of clots.
So far, the EMA, Canada and the World Health Organization hold the view that the benefits of the Oxford vaccine and AstraZeneca outweigh the risks of side effects.
However, it is expected that the report of the EMA safety committee can clarify whether this vaccine is associated with the formation of clots in people who received it or if there are other causes that explain this phenomenon.
Do you have questions about the coronavirus?
Send me your questions on Twitter, we will try to answer them in our next episodes. You can find me in @DrHuerta. You see that we answer them.
If you think this podcast is helpful, help others find it by rating and reviewing it on your favorite podcast app. We will be back tomorrow so be sure to subscribe to get the latest episode on your account.
And for the most up-to-date information, you can always head over to CNNEspanol.com. Thanks for your attention.
[ad_2]
