In an atmosphere like the ones we are going through, there is no doubt that the recent announcement by the two "Pfizer" and "Biontech", about initial success in their third phase experiments on a new vaccine against the emerging corona, was an opportunity to feel some relief while we are surrounded by all the reasons for frustration, in our country it seems The second wave of the epidemic is coming with greater severity, and in the whole world we record daily the number of cases that are close to a million, as for deaths, despite their improvement, they surpassed the height of the first wave last summer, and in all of them we are heading for a million and a half deaths!
The announcement (1), issued by the two companies a few days ago, stated that an early analysis had reported a 90% efficacy of the new vaccine, called "BNT162b2", which is being tested by more than 43,000 people around the world, but the first question must have come. Your mind with the announcement is: What does it mean for the vaccine to be 90% effective?
When the vaccine is tested, we divide the subjects into two groups, the first receiving a real vaccine, and the second receiving a placebo vaccine that gives the same side effects but without a medical effect, the participants in the trials do not know which vaccines they received, then we start to search for cases of "Covid-19" "Within the two groups, here it appeared that there were 94 cases of infection, more than 90% of them were in the placebo group, and the rest were in the group that took the real vaccine.
For this reason, these are called the results of an early analysis (2) (Interim analysis), and in medical sciences this term means obtaining initial results, and scientists conduct this type of analyzes to evaluate the effectiveness of the vaccine before the final results appear. If the effectiveness is promising, then the experiments are completed. According to the usual protocols in this range, scientists were supposed to start calculating results when the number of cases infected with "Covid-19" of the vaccine recipients reached 164 cases, but this happened only with the first 94 cases.
Although there is still a chance for the results to fluctuate, the 90% effectiveness is a surprise, even if it does come down, it is not expected to cross the 50% barrier down, which is the limit set by the US Food and Drug Administration (FDA) to accept the approval of giving approvals for a vaccine, for this reason it is planned "Pfizer" and "Biontech" to submit a request for approval for the emergency use of the vaccine.
The "BNT162b2" vaccine is a nucleic acid (3) mRNA vaccine, and to understand that, let's start with the biology of the secondary stage, any kind of DNA that consists of a very long line of complex chemical letters, but let's imagine that it is a long tape of one of the old videos, on The length of the line of this brown tape records the various scenes, here for example the hero meets the heroine for the first time, and there he leaves her to travel in search of money, in another piece of tape you can find him returning to her in deep regret. DNA is also made up of codes or blades, here is a code that determines your height, and there is another code that determines the color of your eyes, and a third specifies the nature of your hair, each code on the DNA is translated as we grow into that characteristic that it represents.
All living things contain DNA. In the case of viruses, the DNA carries the codes for making the parts of the virus, and in the vaccines of the companies "Pfizer" and "Biontech", the vaccine contains a piece of DNA called "mRNA", once it is injected into the human muscles until It enters the cells that are working to translate it in the way you know it, but here it is translated into a piece of the emerging corona virus called "spike protein" (4) (Spike Protein), which triggers an immune response by the body.
When a virus attacks our body, our immune system deals with this attack in two ways, the first is direct action to end this attack, and the second is working to copy the information of this invader coming from outside, and based on this information, the immune system builds a defense line ready for any attack In the future by the same type of virus.
If you are exposed to this virus for the first time, your immune system takes time to adapt to the new situation and deal with it, and in the meantime symptoms of the disease appear, such as fever, cough or high temperatures, which are symptoms of this conflict inside, but the next time when the virus enters To your body the latter is ready for it, so it deals quickly.
The vaccine - any vaccine - aims to create this type of adaptive immunity against the virus without experiencing a primary infection with it, by stimulating our immune system to a specific type of virus - the emerging corona in this case - so it rushes to prepare itself for a future infection, but on the simplicity of the idea that Through it, that immunity can be created, it is very delicate and very complicated.
The "mRNA" type vaccine has several advantages that make it a promising attempt, not only for the case of the new Corona, but also for vaccine science in general, as it is firstly safer than the usual vaccines that rely on the use of dead or weakened copies of the virus, because that last type of Vaccines may cause disease, on the other hand, the mechanism for manufacturing it is easier and faster, which opens the door to the possibility of producing large quantities in record time.
The story (5) of the "Pfizer-Biontech" vaccine began in May 2020 when the research team of the two companies launched initial trials for two types of the vaccine, the results came to say that both types produced an appropriate immune response, but the second vaccine, which is "BNT162b2", produced less than Side effects, which ranged from fatigue, headache, chills, and muscle and joint pain, the second vaccine entered the third phase with trials on 30,000 people, and then extended to 43,000 people so far, and in addition to effectiveness, the results of the safety of the vaccine remained the same.
The two companies are expected to obtain emergency approval for use soon, and they have announced that by the end of the year 50 million doses can be produced with the possibility that next year we will get 1.3 billion doses. Of course, there will be priorities for distributing the vaccine, whether for specific age groups (the elderly) or groups. Specific sickness or specific job groups (health care workers in general), and political factors will interfere, of course, as each country pays in advance to companies to be in an advanced order in the line of needy people.
This means that it may take us to the end of 2021 for this particular vaccine to reach our hands, but the team of "Pfizer" and "Biontech" is not only the only player in the race to obtain a vaccine, in fact - while we talk - there are 11 other vaccines in the stage The third is for experimentation, among them is the moderna vaccine that works in the same way, and thus it received a lot of attention after the announcement of the initial success of the "Pfizer-Biontech" vaccine.
The two companies, Oxford and AstraZeneca, are also working (6) on a new vaccine that is believed to be ready for mass production before the end of the year. The vaccine is currently undergoing about 40,000 people in Britain, the United States of America, South Africa and Brazil, with a set of tests for children, while China is entering this. The race with two vaccines, the first is the Sinopharma vaccine, and the second is the Sinovac vaccine, and they have entered the third phase of testing in Wuhan, Beijing, the United Arab Emirates, Egypt, Bahrain, Morocco and Jordan, and it is believed that the first vaccine can produce about 220 million doses annually upon passing the phase Third and obtaining the required international approvals.
On the other hand, Russia enters the race with its vaccine, which has sparked controversy recently, and we have provided a separate report for it (7). As for India, it is entering the race with the “Kovaxin” vaccine (8), and like the Chinese vaccines, this vaccine depends on the old method of using dead or weakened viruses, The Indian Council of Medical Research, the National Institute of Virology and the Indian company Bharat Biotech are cooperating in this vaccine, and it had recently announced that it would not be ready for action before the beginning of 2021.
However, despite all the promising results of the "Pfizer-Biontech" vaccine, a number of questions remain firmly on the discussion table, and it is still possible that it affects the course of events (9). For example, how effective does a vaccine stand? Will it prevent the disease completely or relieve its symptoms? We are talking here in particular about those cases in which the virus causes serious symptoms and represents 20% of the people. The initial results of the "Pfizer-Biontech" vaccine were moderate to mild cases.
On the other hand, studying the effect of the vaccine on chronically ill people and the elderly, whether in terms of efficacy or safety, is something that needs further examination, because these experiments focused - mainly - on other categories of volunteers, in addition to that it is necessary to study The effect of the vaccine on different groups of human races, and the companies "Pfizer" and "Biontech" have announced that about 40% of those subject to trials in the United States of America are actually from various ethnic groups, which gives some reassurance.
And the most important question on the table so far remains: “How effective will the vaccine last?” Is it 3 months, 6 months, or a year? Of course, any result would be acceptable under such a circumstance, but this number will strongly affect countries' plans for their future with an epidemic that some studies believe will continue with us until 2025, on the other hand, the short period imposes economic burdens on some countries, especially since we know that the agreement ( 10) "Pfizer-Biontech" with the US government was on $ 39 for each vaccine dose (two syringes separated by 21 days). One of the additional economic problems is how to store these doses, as it requires preservation at 70-80 degrees below zero.
For these reasons, even with the acquisition of the vaccine, the precautionary measures will continue until the year 2022, the precautionary measures will not be withdrawn before fully confirming the effectiveness of the vaccine for all age groups and patients, as well as the period during which the vaccine remains effective, on the other hand, even with The effectiveness of the vaccine, the end of the epidemic will not be easy.
According to a recent study (11) from the American Journal of Preventive Medicine, if the effectiveness of the vaccine is about 80%, then the complete elimination of the epidemic requires that 75% of people use it, but if the effectiveness of the vaccine decreases without that, then That will require a larger population, and this is difficult to happen, at least in a short period of time. The seasonal influenza vaccine, for example, does not end the epidemic, but at least it reduces it by 40-60%.
As for the case of the new Corona, this is what is required as a start, the main problem that we face so far is the collapse of health systems at the height of the virus wave, and mitigating this peak will strongly affect the effectiveness of the health system, and thus the virus can be confronted more easily, but this means that some measures - At least wearing masks and washing hands - it will last longer, in fact just avoiding the lockdown measures is in itself a tremendous success, because at least it will prevent the economy from collapsing in many countries.
In any case, the results for all vaccines, including the "Pfizer-Biontech" vaccine, are very promising so far, not sure of course, but there is a very high chance of success, so all that is required of you is some patience, winter is coming and it is believed that the wave of the virus The coming to us will be more rampant, if you have been a little lazy because of the wave’s decline in the summer, then return to the precautionary measures as you can, and prepare for what is coming, and you know that the length of the ordeal does not mean that it will last forever, but it may be closer than you think, but just be patient.