The Covid19 vaccine (in detail)
The Covid19 vaccine (in detail)Last update: 15/06/2021
This is a highly innovative technology which is very different to traditional vaccines. The latter involve injecting the virus into the body, in either attenuated or inactivated form, to stimulate an immune response. The messenger RNA technique, on the other hand, involves sending a message – a bit like a ‘recipe’ to follow – which is then quickly destroyed.
As their name suggests, these vaccines contain RNA, a molecule almost identical to DNA and found in all living beings. RNA is described as “messenger RNA” (mRNA) when its shape temporarily copies that of a fragment of DNA. It transcribes the genetic information of a part of the virus. The mRNA strands injected into the body carry the coronavirus genes responsible for making a protein.
Once injected, the mRNA enters human cells. The genes are “read” by the “cell factories”, which make the protein. Roughly speaking, the body is given a kind of barcode for the coronavirus. The immune system will make the antibodies.
The proteins, produced in large numbers by the cells, are then detected, and this triggers an immune reaction.
In other words, the immune system will make antibodies to destroy the coronavirus. These same antibodies will be able to recognise and effectively fight the coronavirus if it later attempts to infect the body.
Once the RNA has been “read”, it is quickly destroyed and no trace of it is left in the body.
Since this technique prompts a moderate immune response, it requires the administration of two doses, 21 days apart, to ensure lasting protection.
Pfizer/BioNtech contains an mRNA molecule which has instructions for making a protein of SARS-CoV-2, the virus that causes COVID-19. Pfizer/BioNtech does not contain the virus itself and cannot cause COVID-19.
Pfizer/BioNtech works by preparing the body to defend itself against COVID-19. It contains a molecule called mRNA that holds instructions relating to the production of the spike protein. This is a protein on the surface of the SARS-CoV-2 virus which the virus needs to enter the body’s cells.
When a person is given the vaccine, some of their cells will read the mRNA instructions and temporarily produce the spike protein. The person’s immune system will then recognise this protein as foreign and produce antibodies and activate T cells (white blood cells) to attack it.
If the person later comes into contact with the SARS-CoV-2 virus, their immune system will recognise it and be ready to defend the body against it.
The mRNA from the vaccine does not stay in the body but is broken down shortly after vaccination.
The mRNA vaccine does not contain any adjuvants (aluminium or otherwise).
People who have had COVID-19 can receive the Pfizer/BioNtech vaccine.
However, the Haute Autorité de Santé (HAS, the French National Authority for Health) recommends waiting at least three months after the onset of symptoms before getting vaccinated and that people should not get vaccinated if they have lingering symptoms.
A very large-scale clinical trial showed that Comirnaty was effective in preventing COVID-19 in people aged 16 and over.
Currently, only one vaccine is available, Comirnaty from Pfizer / BioNTech. Europe authorized, on January 6, a second vaccine, that of Moderna. These two vaccines are based on the same platform and are quite similar.
Other vaccines have received authorization from the European Medicines Agency, namely AstraZeneca and Johnson & Johnson. These are two adenovirus vaccines. These two vaccines are the subject of investigations by European and American pharmacovigilance agencies. Currently they are not administered in Monaco.
It depends on the vaccine.
The Pfizer / BioNTech vaccine, currently available, requires a vaccination booster (therefore a second injection at an interval of at least 21 days). This second dose is essential to ensure good immunity.
You will therefore be given a second appointment when you receive your first vaccine dose.
As with all other medicines, the safety of COVID-19 vaccines is monitored once they are available on the market. All side effects are kept under surveillance at the International and European levels. Existing surveillance systems have been strengthened at the European and national levels to monitor COVID-19 vaccines.
All of the scientific data will be publicly accessible via the European Medicines Agency website. After a vaccine is approved, information about the product (leaflet and summary of product characteristics (SmPC)), the European public assessment report (EPAR), the risk management plan (RMP) and clinical trial data will be available. Once the product is marketed, data on side effects will also be available.
Like any medication, vaccines can produce side effects, but these do not affect everyone.
The HAS and the European Medicines Agency are working on this issue and will disseminate information as effects are noted.
So far, we have seen that some people in the United Kingdom, where vaccination has already begun using the Pfizer vaccine, have experienced the following side effects: redness at the injection site, fatigue, headaches and, to a lesser extent, shivering, aches, fever and allergic reactions.
In rare instances, more severe reactions may also occur. The risk of serious or lasting side effects is very low but can never be excluded. This applies not just to COVID-19 vaccines, but to any medication, including all vaccines.
Suspected side effects should be reported to the healthcare professional who gave you the vaccination or, if you were vaccinated at the National Vaccination Centre or by a mobile vaccination team, by telephoning 22.214.171.124 or 126.96.36.199 or emailing: [email protected].
The risk of getting COVID-19 is much lower in people who have received the vaccine, but this vaccine - like any other vaccine - is not 100% effective.
Vaccines available today or under development reduce the severity of symptoms.
When a person receives a vaccine, they are not immediately protected. Vaccine efficacy is obtained 7 to 14 days after injection (2 doses for most vaccines, 1 dose for Johnson and Johnson).
Even vaccinated, you could be infected without knowing it and transmit the virus to relatives. Wearing a mask therefore remains necessary.