- 10 Dec 2020 11:55
#15142243
Vaccines are the success story of modern medicine. The history of modern vaccines starts with the smallpox vaccine in the 18th century; however, there are reports of primitive forms of vaccine in China or Africa centuries before that.
While the first vaccines used live viruses, which involves a considerable risk, most vaccines today use dead or deactivated viruses to reduce the risk of infection. The immune system recognizes the virus even after it has been deactivated and thus rendered harmless. The Chinese and Russians primarily use this technology for their Covid-19 vaccines.
Traditionally, it takes years to develop and test a new vaccine; however, due to the inability of Western countries to cope with the pandemic by any other means, the development, testing and regulatory approval of Covid-19 vaccines has been reduced to less than a year.
Does that mean these vaccines aren't safe? Not necessarily. As I said, the technology of traditional deactivated virus vaccines is well known. The delivery mechanisms are known and tested. It's just a matter of developing and producing the virus-specific payload. That in itself is cumbersome and time-consuming. It takes time and a huge amount of eggs to produce the vaccine payload. Since the vaccine material is limited, an adjuvant is typically used to boost the effect of vaccine, especially for the elderly who have a reduced immune response. Depending on the type of adjuvant used, this can sometimes lead to problems with side-effects.
In the West, a totally new technology for producing vaccines has been used for Covid-19. The so-called messenger RNA, or mRNA, vaccines developed by Pfizer/Biontech, Moderna, Curevac, etc., and the DNA vaccine developed by AstraZeneca have never been used for mass vaccination of humans before. They aren't totally new. Biontech and Curevac are two German start-ups created specifically for developing the mRNA technology. Biontech has focused on cancer treatment with mRNA for about 20 years, but the company already partnered with Pfizer a couple of years ago to develop mRNA vaccines for Zika and flu viruses.
The Zika and flu mRNA vaccines weren't very effective and there seem to have been considerable autoimmune problems due to the vaccination. Since the Zika virus is not a problem anymore and there are plenty of other flu vaccines, the mRNA vaccines weren't in the end used for mass vaccination. The autoimmune problems with the Zika and flu viruses may have led Pfizer/Biontech to exclude people with a history of severe allergic reactions from their 3rd phase Covid-19 vaccine trial. It is therefore surprising that the NHS in the UK rushed to use the vaccine for two of its own employees with a history of severe allergic reaction.
The mRNA vaccines can be industrially produced in large quantities without using eggs. In theory, they are also safer than traditional deactivated virus vaccines because no viruses or even parts of viruses are introduced into the human body. The only thing that's introduced is the genetic code of the virus' spike protein it uses for docking to the human ACE2 receptors. The mRNA genetic code is encapsulated in lipid nanoparticles and refrigerated at low temperatures because it is very instable. Following vaccination, the mRNA code of the spike protein enters the cytoplasm of human cells were it produces proteins that look like the virus' spike protein. The immune system recognizes and memorizes the spike protein to produce t-cells and antigens when it is infected by SARS-CoV-2.
Thus, instead of producing a vaccine on eggs, the human body is used to produce the vaccine based on the mRNA code. Since only part of the virus RNA is introduced, it is unthinkable that the human DNA should be somehow modified. And since the mRNA is very instable, it'll disappear soon, only leaving the memory of the spike protein in the immune system. It is therefore likely that if there is a side-effect, it'll be soon after vaccination, as in the case of the allergic reaction in the two NHS employees in the UK.
22,000 people were vaccinated with the new Pfizer/Biontech mRNA vaccine without severe side-effects; however, when hundreds of millions are vaccinated, it's likely that there will be individual cases with severe side-effects. Anyways, from what is known at this point of time, anybody who has to carry an EpiPen to prevent an anaphylactic shock better wait for another vaccine.
The mRNA technology has the potential to revolutionize vaccines and cancer treatment. It's easy and fast to produce, can be highly effective and doesn't require an adjuvant for boosting since it's easy to industrially produce large amounts of vaccine. It can reduce the risk associated with traditional vaccines. At this point, the only worry is that it has never been used in large scale human vaccination. Once established as a carrier technology, payloads for new viruses that may appear in the future could be developed in record time.
I can't link the documents to all of the above information, but here's a good discussion to get started. You can always Google for more.
Want to know more about mRNA before your Covid jab?
While the first vaccines used live viruses, which involves a considerable risk, most vaccines today use dead or deactivated viruses to reduce the risk of infection. The immune system recognizes the virus even after it has been deactivated and thus rendered harmless. The Chinese and Russians primarily use this technology for their Covid-19 vaccines.
Traditionally, it takes years to develop and test a new vaccine; however, due to the inability of Western countries to cope with the pandemic by any other means, the development, testing and regulatory approval of Covid-19 vaccines has been reduced to less than a year.
Does that mean these vaccines aren't safe? Not necessarily. As I said, the technology of traditional deactivated virus vaccines is well known. The delivery mechanisms are known and tested. It's just a matter of developing and producing the virus-specific payload. That in itself is cumbersome and time-consuming. It takes time and a huge amount of eggs to produce the vaccine payload. Since the vaccine material is limited, an adjuvant is typically used to boost the effect of vaccine, especially for the elderly who have a reduced immune response. Depending on the type of adjuvant used, this can sometimes lead to problems with side-effects.
In the West, a totally new technology for producing vaccines has been used for Covid-19. The so-called messenger RNA, or mRNA, vaccines developed by Pfizer/Biontech, Moderna, Curevac, etc., and the DNA vaccine developed by AstraZeneca have never been used for mass vaccination of humans before. They aren't totally new. Biontech and Curevac are two German start-ups created specifically for developing the mRNA technology. Biontech has focused on cancer treatment with mRNA for about 20 years, but the company already partnered with Pfizer a couple of years ago to develop mRNA vaccines for Zika and flu viruses.
The Zika and flu mRNA vaccines weren't very effective and there seem to have been considerable autoimmune problems due to the vaccination. Since the Zika virus is not a problem anymore and there are plenty of other flu vaccines, the mRNA vaccines weren't in the end used for mass vaccination. The autoimmune problems with the Zika and flu viruses may have led Pfizer/Biontech to exclude people with a history of severe allergic reactions from their 3rd phase Covid-19 vaccine trial. It is therefore surprising that the NHS in the UK rushed to use the vaccine for two of its own employees with a history of severe allergic reaction.
The mRNA vaccines can be industrially produced in large quantities without using eggs. In theory, they are also safer than traditional deactivated virus vaccines because no viruses or even parts of viruses are introduced into the human body. The only thing that's introduced is the genetic code of the virus' spike protein it uses for docking to the human ACE2 receptors. The mRNA genetic code is encapsulated in lipid nanoparticles and refrigerated at low temperatures because it is very instable. Following vaccination, the mRNA code of the spike protein enters the cytoplasm of human cells were it produces proteins that look like the virus' spike protein. The immune system recognizes and memorizes the spike protein to produce t-cells and antigens when it is infected by SARS-CoV-2.
Thus, instead of producing a vaccine on eggs, the human body is used to produce the vaccine based on the mRNA code. Since only part of the virus RNA is introduced, it is unthinkable that the human DNA should be somehow modified. And since the mRNA is very instable, it'll disappear soon, only leaving the memory of the spike protein in the immune system. It is therefore likely that if there is a side-effect, it'll be soon after vaccination, as in the case of the allergic reaction in the two NHS employees in the UK.
22,000 people were vaccinated with the new Pfizer/Biontech mRNA vaccine without severe side-effects; however, when hundreds of millions are vaccinated, it's likely that there will be individual cases with severe side-effects. Anyways, from what is known at this point of time, anybody who has to carry an EpiPen to prevent an anaphylactic shock better wait for another vaccine.
The mRNA technology has the potential to revolutionize vaccines and cancer treatment. It's easy and fast to produce, can be highly effective and doesn't require an adjuvant for boosting since it's easy to industrially produce large amounts of vaccine. It can reduce the risk associated with traditional vaccines. At this point, the only worry is that it has never been used in large scale human vaccination. Once established as a carrier technology, payloads for new viruses that may appear in the future could be developed in record time.
I can't link the documents to all of the above information, but here's a good discussion to get started. You can always Google for more.
Want to know more about mRNA before your Covid jab?