The anti Covid-19 vaccine represents today an effective weapon to face and definitively defeat the pandemic, which is still underway. To avoid alarmism and disinformation it is essential to know it and to dispel the main doubts relating to vaccination.
Read all the questions you have probably asked yourself and deepen them with the answers provided by AIFA , the Italian Medicines Agency, and by the Ministry of Health .
The Covid-19 vaccine: what is it and how is it administered?
The COVID-19 mRNA BNT162b2 (Comirnaty) vaccine is a vaccine intended to prevent Coronavirus disease in individuals aged 16 years and older. It contains a molecule called messenger RNA (mRNA) with instructions for making a protein found on SARS-CoV-2, the virus responsible for COVID-19: the vaccine does not contain the actual virus , but only the genetic information, and therefore it cannot cause disease.
For administration, the vaccine requires two injections , usually into the muscle of the upper arm, at least 21 days apart .
But how does the vaccine work? Using a protein , called Spike , SARS-CoV-2 viruses infect people: all the vaccines currently under study have been developed to induce a response that blocks this 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, thereby stimulating the immune system to produce specific antibodies .
How was the experimentation conducted?
A large-scale clinical study was conducted for the Pfizer vaccine , which highlighted its effectiveness in preventing Covid-19 in subjects aged 16 and over. The searches took place in six different countries , involving over 44,000 people .
Only half of the participants in the clinical trial received the vaccine, while the other half received a placebo, which is a product identical to the vaccine, but not active. Evidence showed that the number of symptomatic cases of Covid-19 was reduced by 95% in those who received the vaccine (8 cases out of 18,198 had symptoms of Covid-19) compared to those who received placebo (162 cases of 18,325 had symptoms of Covid-19).
Although the trial of Covid-19 vaccines lasted a few months compared to the usual times, the number of participants was significantly higher. This was a key element that made it possible to carry out a large study, thus demonstrating its efficacy and safety .
None of the regular phases of vaccine testing have been overlooked: the speed of the experimentation is also due to the research produced in previous years relating to RNA vaccines and the huge economic and human resources made available.
Covid-19 vaccine: efficacy, protection and adverse reactions
The results of these studies have shown that two doses of the vaccine administered 21 days apart can prevent 95% of adults aged 16 and over from developing the COVID-19 disease with substantially homogeneous results for classes of age, gender and ethnicity.
The protection is not effective immediately after the injection, but one week after the second dose . The duration of protection is not yet defined with certainty, but knowledge about other types of coronaviruses indicates that it should be at least 9-12 months .
With regard to the transmission of the virus to already vaccinated people, given that clear evidence is not yet available, it is necessary that the vaccinated and those in contact with them continue to take protective measures .
The most frequently observed adverse reactions were generally mild or moderate in severity and resolved within days of vaccination. The main ones were:
- pain and swelling at the injection site;
- pain in the muscles and joints;
- chills and fever.
In case of development of any reaction to the administration of the vaccine, you can report to your general practitioner or to the ASL you belong to .
What are the possible contraindications in particular cases?
People with severe allergies will need to consult with their doctor before undergoing the vaccination. As with all vaccines, this too will need to be administered under close medical supervision . Although there have been very few cases of severe allergic reaction, if it occurs they will not have to receive a second dose.
Furthermore, the vaccine is not contraindicated and does not exclude pregnant women : in general, vaccination during pregnancy and lactation should be established following a consultation with a healthcare professional, considering its risks and benefits .
People with chronic diseases, diabetes, cancer and cardiovascular disease are the most at risk and are the ones who need to have priority for vaccination. While the vaccine is contraindicated for children , a special vaccination will be tested later.
For subjects undergoing anticoagulant treatment , vaccination, as well as for all types of injections, is not recommended and must be carefully evaluated to avoid the risk of bleeding. Instead, it is recommended for all people who have had the flu vaccine to wait a couple of weeks before proceeding with the Covid-19 vaccination.
The issue of a certificate of successful vaccination is usually expected : the European Commission and the WHO (World Health Organization) are currently evaluating a proposal for an international digital certificate .
We remind you that from 31 December 2020 the Ministry of Health has activated a dashboard where the data and statistics relating to the administration of vaccines throughout the national territory are collected .