Everything you need to know about the Pfizer-Biontech vaccine. Aifa report
The anti Covid vaccinations are also starting in Italy. Here's everything you need to know about the vaccine. The Aifa faq
CHARACTERISTICS OF THE VACCINE
COVID-19 mRNA BNT162b2 vaccine (Comirnaty)
COVID-19 mRNA vaccine.
1.What is it and what is it used for?
The COVID-19 mRNA BNT162b2 (Comirnaty) vaccine is a vaccine intended to prevent coronavirus disease 2019 (COVID-19) in individuals aged 16 years and older. It contains a molecule called messenger RNA (mRNA) with instructions for making a protein found on SARSCoV-2, the virus responsible for COVID-19.
The vaccine does not contain the virus and cannot cause disease.
2. How is it administered?
The COVID-19 mRNA BNT162b2 (Comirnaty) vaccine is given as two injections, usually into the muscle of the upper arm, at least 21 days apart.
3. How does it work?
SARS-CoV-2 viruses infect people using a surface protein, called Spike, which acts as a key allowing viruses to enter cells, where they can then reproduce. All the vaccines currently under study have been developed to induce a response that blocks the Spike protein and thus prevents cell infection. The COVID-19 mRNA BNT162b2 (Comirnaty) vaccine is made with messenger ribonucleic acid (mRNA) molecules that contain instructions for the vaccinated person's cells to synthesize Spike proteins. In the vaccine, the mRNA molecules are inserted into a microscopic lipid vesicle that allows the mRNA to enter the cells. Once injected, the mRNA is absorbed into the cytoplasm of cells and initiates the synthesis of Spike proteins.
The proteins produced stimulate the immune system to produce specific antibodies. In those who have been vaccinated and are exposed to viral infection, the antibodies thus produced block the Spike proteins and prevent their entry into the cells.
Furthermore, vaccination also activates T cells that prepare the immune system to respond to further exposure to SARS-CoV-2. The vaccine, therefore, does not introduce the actual virus into the cells of the vaccineer, but only the genetic information that the cell needs to build copies of the Spike protein. Should the vaccinated person come into contact with SARSCoV-2 again at a later stage, their immune system will recognize the virus and be ready to fight it. The vaccine mRNA does not remain in the body but degrades shortly after vaccination.
4. What does it contain?
COVID-19 mRNA BNT162b2 (Comirnaty) contains a messenger RNA that cannot propagate itself in host cells, but induces the synthesis of SARS-CoV-2 virus antigens (which it codes for itself). The S antigens of the virus stimulate the antibody response of the vaccinated person with production of neutralizing antibodies.
The messenger RNA is enclosed in liposomes formed by ALC-0315 ((4-hydroxybutyl) azanediyl) bis (hexane6,1-diyl) bis (2-hexyldecanoate) and ALC-0159 (2 – [(polyethylene glycol) -2000] – N, N-dithetradecylacetamide) to facilitate entry into cells.
The vaccine also contains other excipients:
- 1,2-Distearoyl-sn-glycero-3-phosphocholine
- cholesterol
- Potassium chloride
- Potassium dihydrogen phosphate
- Sodium chloride
- Disodium phosphate dihydrate
- sucrose
- water for injections
EFFECTIVENESS AND SAFETY OF VACCINATION
5. Was the trial shortened to have the product soon?
Studies on COVID-19 vaccines, including the COVID-19 mRNA vaccine BNT162b2 (Comirnaty), began in spring 2020, so they lasted a few months compared to usual times, but saw the participation of a very large number of people: ten times higher than the standards of similar vaccine development studies. Therefore it was possible to carry out a large study
size, sufficient to demonstrate efficacy and safety.
None of the regular phases of verification of the efficacy and safety of the vaccine have been skipped: the short times that led to rapid registration have been made possible thanks to the research carried out for many years on RNA vaccines, to the great human resources and made available in a very short time and to the evaluation of the regulatory agencies of the results obtained as they were produced and not, as is customary, only when all the studies are completed. These simple measures have saved years on approval times.
6. How were the clinical studies conducted?
A very large clinical study has shown that the COVID-19 mRNA BNT162b2 (Comirnaty) vaccine is effective in preventing COVID-19 in people aged 16 years and older. The safety and efficacy profile of this vaccine was evaluated in research conducted in six countries: the United States, Germany, Brazil, Argentina, South Africa and Turkey, with the participation of over 44,000 people. Half of the participants received the vaccine, the other half received a placebo, a product identical in all respects to the vaccine, but not active. The efficacy has been calculated on over 36,000 people aged 16 years and older (including subjects over the age of
75 years old) who showed no signs of previous infection.
The study showed that the number of symptomatic cases of COVID-19 was reduced by 95% in subjects who received the vaccine (8 of 18,198 cases had symptoms of COVID-19) compared to those who received placebo (162 cases of 18,325 had symptoms of COVID-19).
7. How effective is it?
The results of these studies showed that two doses of the COVID-19 mRNA BNT162b2 (Comirnaty) vaccine given 21 days apart can prevent 95% of adults aged 16 and over from developing COVID- 19 with substantially homogeneous results by age, gender and ethnic group.
The 95% reduction refers to the difference between the 162 cases that occurred in the group of over 18 thousand who received the placebo and the only 8 cases that occurred in the over 18 thousand who received the vaccine.
8. Is the protection effective immediately after the injection?
No, the efficacy was demonstrated one week after the second dose.
9. How long does the vaccine induced protection last?
The duration of protection is not yet defined with certainty because the observation period was necessarily a few months, but knowledge on other types of coronaviruses indicates that protection should be at least 9-12 months.
10. Can the vaccine cause COVID-19 disease or other genetic alterations?
This vaccine does not use active viruses, but only a genetic component that brings information into the body of the vaccinator to produce specific antibodies. There are no whole or live viruses involved, so the vaccine cannot cause disease. Vaccine mRNA like all mRNA produced by cells naturally degrades after a few days in the person receiving it.
11. Can vaccinated people still transmit the infection to other people?
Clinical studies conducted so far have allowed to evaluate the efficacy of COVID-19 mRNA BNT162b2 (Comirnaty) vaccine on clinically manifest forms of COVID-19 and more time is needed to obtain meaningful data to demonstrate whether vaccinated can be infected asymptomatically and infect other people. While it is plausible that vaccination protects against infection, vaccinated people and people who are in contact with them must continue to take protective measures against COVID-19.
12. Who performs the first dose of COVID-19 mRNA BNT162b2 (Comirnaty) vaccine, can they do the second dose with another Covid-19 vaccine, if available?
There are still no data on the interchangeability between different vaccines, so those who undergo vaccination at the first dose with the COVID-19 mRNA vaccine BNT162b2 (Comirnaty), will continue to use the same vaccine for the second dose.
13. What adverse reactions have been observed?
The most frequently observed adverse reactions (more than 1 in 10 people) in the COVID-19 mRNA BNT162b2 (Comirnaty) vaccine study were generally mild or moderate in severity and resolved within days of vaccination. These included pain and swelling at the injection site, fatigue, headache, pain in muscles and joints, chills and fever.
Injection site redness and nausea occurred in less than 1 in 10 people. Injection site itching, pain in limbs, swollen lymph nodes, difficulty falling asleep and feeling sick were uncommon, affecting fewer than 1 in 100 people. Weakness in the muscles of one side of the face (acute peripheral facial paralysis) has occurred rarely, in less than 1 in 1000 people.
14. What serious adverse reactions were observed during the trial?
The only severe adverse reaction more frequent in the vaccinated than in the placebo group was enlargement of the lymph glands. However, it is a benign disease that heals on its own.
In general, systemic reactions were more frequent and pronounced after the second dose.
In countries where mass administration of the vaccine has already begun, reports of adverse reactions have also begun, from the least serious to the most significant, including allergic reactions. All countries that initiate the administration of the vaccine extended to the entire population will collect and evaluate every report received by the drug surveillance system of adverse reactions to the vaccine, so as to be able to define with ever greater precision the type of risk profile linked to vaccination.
15. Who develops a reaction to the administration to whom can communicate it?
The reporting of any reaction to the administration of the vaccine can be made to your family doctor or to the ASL of belonging, as well as for all other adverse reactions to any drug, according to the national pharmacovigilance system active for some time throughout the country.
In addition, anyone can report a vaccine adverse reaction in the first person using the forms published on the AIFA website:
https://www.aifa.gov.it/content/segnalazioni-reazioni-avverse.
16. How is the absence of contraindications detected?
Before vaccination, healthcare personnel ask the person to be vaccinated a series of precise and simple questions, using a standardized form. If the healthcare provider finds significant responses to questions, consider whether the vaccination can be given or postponed. Furthermore, the operator checks for the presence of contraindications or particular precautions, as also reported in the vaccine data sheet.
17. A new variant of the SARS-CoV-2 virus has been reported: will the vaccine also be effective against this new variant?
RNA viruses such as SARS-CoV-2 are subject to frequent mutations, the majority of which do not significantly alter the structure and components of the virus. Many variants of SARS-CoV-2 were reported in 2020, but so far these variants have not altered the natural behavior of the virus.
The variant reported in England is the result of a series of protein mutations on the surface of the virus and evaluations are underway on the effects that these may have on the progress of the epidemic, while a negative effect on vaccination appears unlikely.
SPECIAL CONDITIONS
18. Anyone who has already had a confirmed COVID-19 infection must or can be vaccinated?
Vaccination does not contrast with a previous COVID-19 infection, rather it enhances his immune memory, so no pre-vaccination test is useful. However, those diagnosed with COVID-19 positivity do not need vaccination in the first phase of the vaccination campaign, while it could be considered when obtaining data on the
duration of immune protection.
19. Can people with allergies get vaccinated with the COVID-19 mRNA BNT162b2 (Comirnaty) vaccine?
People with a history of severe anaphylactic reactions or severe allergy, or who are already aware that they are allergic to one of the components of the BNT162b2 (Comirnaty) mRNA vaccine, should consult with their doctor before undergoing the vaccination.
As with all vaccines, this too must be administered under close medical supervision.
People who experience a severe allergic reaction after receiving the first dose of the vaccine should not receive the second dose.
Allergic (hypersensitivity) reactions have been observed in subjects given the vaccine. Since the vaccine began to be used in vaccination campaigns, there have been very few cases of anaphylaxis (severe allergic reaction).
20. Can pregnant or breastfeeding women be vaccinated?
Data on the use of the vaccine during pregnancy are still very limited, however laboratory studies on animal models have shown no harmful effects in pregnancy. The vaccine is not contraindicated and does not exclude pregnant women from vaccination, because pregnancy, especially when combined with other risk factors such as diabetes, cardiovascular disease and obesity, could make them more at risk of severe COVID-19. The Istituto Superiore di Sanità has in place a surveillance system on pregnant women in relation to COVID-19 that could offer further useful information.
Although there are no studies on breastfeeding, based on biological plausibility there is no risk that prevents continuing breastfeeding.
In general, the use of the vaccine during pregnancy and breastfeeding should be decided in close consultation with a healthcare professional after considering the benefits and risks.
21. Can children be vaccinated with the COVID-19 mRNA BNT162b2 (Comirnaty) vaccine?
This vaccine is not currently recommended for children under the age of 16. The European Medicines Agency (EMA) has agreed with the manufacturer on a plan for testing the vaccine in children at a later stage.
22. Can people with documented immunodeficiency or autoimmune diseases be vaccinated?
No data are yet available on the safety and efficacy of COVID-19 mRNA BNT162b2 (Comirnaty) vaccine in people with autoimmune diseases, but they were included in the initial trials. During the clinical trials, no differences were observed in the appearance of symptoms attributable to autoimmune or inflammatory diseases between vaccinated and placebo treated subjects. People with autoimmune diseases who have no contraindications can receive the vaccine.
Data on use in immunocompromised people (whose immune systems are weakened) are limited. While these people may not respond as well to the vaccine, there are no particular safety concerns. Immunocompromised people can be vaccinated as they may be at high risk for COVID-19.
23. Can people with chronic diseases, diabetes, cancer, cardiovascular disease be vaccinated?
These are precisely the people most at risk of a serious evolution in case of infection from SARSCoV-2, therefore, priority will be given to them in the invitation to vaccination.
24.Can people being treated with anticoagulants be vaccinated?
People being treated with anticoagulant therapy have a generic contraindication to any injection, for them vaccination must be assessed on a case-by-case basis by their doctor for the risk of bleeding from the injection site.
25. Can people who have had the flu vaccination recently been vaccinated against COVID-19?
There is no data yet on the interference between COVID-19 vaccination and other vaccinations, however the nature of COVID-19 mRNA BNT162b2 (Comirnaty) vaccine suggests that it is unlikely to interfere with other vaccines. However, the spacing of a couple of weeks can be a precautionary measure.
VACCINATION PROCEDURES
26. Who will administer the vaccine?
Vaccination will be carried out by doctors and nurses of the public vaccination services, people who have been vaccinating for a long time and are experts in vaccination techniques. Furthermore, in view of the particularity of this vaccine, healthcare professionals have received additional specific technical information on the preparation and administration of the COVID-19 mRNA BNT162b2 (Comirnaty) vaccine.
27. Who should I contact to get vaccinated?
The vaccination campaign will take place in several successive phases, citizens will be invited to carry out vaccination in an order of priority defined by the risk for people to become infected and develop the disease with serious consequences. In the initial phase, vaccination will be reserved for healthcare personnel and for the staff and guests of residences for the elderly and vaccinations will be carried out by the staff of the vaccination services in the 286 hospitals defined by the National COVID-19 vaccination plan. The same vaccination staff will go to the nursing homes for vaccination.
28. How much does the vaccination cost?
Vaccination is free for everyone.
29. Is it possible to get vaccinated privately for a fee?
No, the vaccines currently available will only be used in the facilities defined by the Vaccine Plan and will not be available in pharmacies or in the private market. It is highly discouraged to try to obtain the vaccine by alternative means or on the internet. These channels do not give any guarantee on the quality of the product, which could be, in addition to being ineffective, dangerous for health.
30. Does the vaccine protect only the vaccinated person or also their family members?
The vaccine protects the individual person, but if there are many who vaccinate ourselves, we could partially reduce the circulation of the virus and therefore also protect all the people who cannot be vaccinated: vaccination is done to protect ourselves, but also the community in we live in.
31. Does vaccination allow you to go back to life as before?
Even if the effectiveness of the COVID-19 mRNA BNT162b2 vaccine is very high (over 90%) there will always be a portion of vaccinated who will not develop the immune defense, moreover, we still do not know definitively if the vaccination only prevents the manifestation disease or even the transmission of infection. This is why being vaccinated does not confer a "certificate of freedom" but it is necessary to continue to adopt correct behaviors and measures to contain the risk of infection.
32. Will there be a vaccine for everyone?
The Italian government, through European procedures, has booked the purchase of over two hundred million doses of COVID-19 vaccines from six different manufacturers. There will be no free choice on which vaccine to prefer: the vaccine available at the time and place will be offered by the vaccination services in full guarantee of equivalent safety and efficacy.
33. What kind of syringes will be used?
Vaccination will be carried out with a special disposable sterile syringe equipped with a needle locking system (Luer Lock) to avoid accidental detachments; the disposable sterile needles are also equipped with a locking attachment: used syringes must not be re-capped (Ministerial Decree 28/9/89) and will be immediately deposited in special disposal containers.
34. Will only Italian citizens be vaccinated?
According to the priority scheme defined in the Vaccines Plan, all persons present in Italy, residents, with or without a residence permit pursuant to article 35 of the consolidated immigration law, will be vaccinated.
35. What documents are required to carry out the vaccination?
A valid identity document and health card. It may also be useful to have any health documentation with you that can help the vaccinator to assess the physical state.
This is a machine translation from Italian language of a post published on Start Magazine at the URL https://www.startmag.it/sanita/efficacia-controindicazioni-e-non-solo-tutto-quello-che-ce-da-sapere-sul-vaccino-pfizer-secondo-aifa/ on Sun, 27 Dec 2020 06:52:02 +0000.