Italian Medicines Agency Agenzia Italiana del Farmaco

Questions and answers on COVID-19 vaccines

Questions and answers


COVID-19 vaccines

28 april 2021

Questions and answers on COVID-19 vaccines

General information on COVID-19 vaccination

As of December 2020, the European Medicines Agency (EMA) has recommended the provisional granting of conditional marketing authorizations for COVID-19 vaccines. AIFA acknowledges the European decisions and therefore authorises the use of such vaccines in Italy.

1. What is the mechanism of action of COVID-19 vaccines?

The SARS-CoV-2 coronavirus, responsible for COVID-19, uses a protein (called 'Spike') which protrudes from its envelope to enter the human cells, where it then reproduces. The vaccines currently available have been developed to induce an immune response capable of blocking the Spike protein, thus preventing the virus from infecting cells. These vaccines introduce into some cells of the human body not the SARS-CoV-2 coronavirus, but the genetic information necessary to produce the Spike protein for a short time. The presence of this foreign protein will stimulate the immune system to react against it by producing antibodies that will prevent the virus from entering and infecting cells through binding to the Spike protein. The presence of the foreign Spike protein will also activate T lymphocytes driving antibody production and killing virus-infected cells. Some of these lymphocytes survive for several months ('memory lymphocytes') and allow the immune system of the immunized person to rapidly activate an extraordinary reaction against a possible SARS-CoV-2 invasion.

2. Was the clinical trial shortened to have these vaccines available quickly?

The studies that led to the development of COVID-19 vaccines did not skip any of the phases of verification of the efficacy and safety required for the development of a medicine; on the contrary, these studies saw the participation of a very large number of volunteers, about ten times higher than that of similar studies for the development of other vaccines. The rapid development and approval is due to new technologies, to the huge resources made available very quickly and to a new evaluation process by the regulatory agencies, which evaluated the results as they were obtained and not when all the studies were completed - as was previously the case.

3. How long does the protection induced by such vaccines last?

The duration of protection has not yet been defined with certainty, because so far the observation period has necessarily been a few months. However, data on other types of coronaviruses suggest that it should be at least 9-12 months.

4. Can vaccinated people still transmit the infection to others?

The aim of the registration studies was to assess the vaccines efficacy in protecting from the COVID-19 disease. Studies are ongoing to determine whether asymptomatically infected vaccinated people can infect others. Since it is possible that, despite protective immunity, in some cases the virus may persist in the nasal mucosa, vaccinated people and those who are in contact with them must continue to take protective measures against COVID-19.

5. Do vaccines protect just the vaccinated person or his/her family too?

Vaccines protect the vaccinated person, but if many people are vaccinated, they can reduce the circulation of the virus, thus protecting also those who are not vaccinated. Vaccination protects those who are vaccinated, but it also helps protect the community where they live.

6. Variants of SARS-CoV-2 virus have been reported: will vaccines be effective also against such variants?

SARS-CoV-2 virus is subject to frequent mutations. The vaccine-induced immune response protects against most of these variants although protection might be less effective against some of them.

7. Why is it not possible to choose the vaccine?

Vaccination against COVID-19 is a right for all, however the risk of contracting the virus and developing the disease in a severe form is not the same for everyone and the availability of doses is currently not the same for all vaccines. Therefore, with an aim to ensure maximum fairness, it is necessary to comply with the Strategic plan for COVID-19 vaccination developed by the Ministry of Health.

Recipients of COVID-19 vaccination

1. Who is entitled to vaccination?

All people residing or permanently present on the Italian territory, with or without a residence permit, who fall within the categories periodically updated by the Vaccination Plan.

2. Can anyone be vaccinated who has already had a COVID-19 infection, confirmed by a molecular test?

People who have had a molecular test-confirmed (or third-generation antigenic) SARS-CoV-2 infection, with or without symptoms, will receive a single dose of the vaccine after at least 3 months, but no later than 6 months after infection. They will instead receive the two doses, if they are immunocompromised or on immunosuppressive therapy. 
Please note that serological or molecular tests before and after vaccination are useless.

3. Shall people be administered the second dose of vaccine if they are infected with SARS-CoV-2 after receiving the first dose?

In people with SARS-CoV-2 infection confirmed by a molecular or antigen test after the first dose of the vaccine, the infection itself represents a powerful trigger for the immune system, which adds to the first dose of vaccine. In light of this and considering that natural infection triggers a specific immune response to the virus, it is not recommended to administer the second vaccine dose to these people. Partial vaccination and subsequent infection do not prevent a possible booster of COVID-19 vaccination in the future, if data on duration of immune protection indicate such need.

4. How is the absence of contraindications to vaccination detected?

Before vaccination, healthcare staff ask the vaccinee a series of simple but precise questions, using a standardized form to assess whether the vaccination can be carried out or postponed. In addition, the healthcare professional checks for any contraindications or special precautions.

5. Who can I contact if I have a reaction after vaccine administration?

Adverse reactions to the vaccine can be reported to general practitioners or to any health professional, in agreement with the pharmacovigilance system in place. Moreover, anyone can report an adverse reaction to the vaccine by using any of tools provided on the AIFA website. For further details, please refer to FAQs on Pharmacovigilance on COVID-19 vaccines and monthly reports on adverse reactions. 

6. Can people who have experienced a severe allergic or non-allergic adverse reaction to the first administration of Covid-19 vaccine receive the second dose?

NO, people having previously experienced severe, allergic and non-allergic reactions, to the first dose, should NOT be administered the second dose, but should contact a referral centre with experience on reactions to vaccinations, to receive specialist information.

NB. A "serious adverse reaction" means that it required hospitalization or prolonged treatment, or that it was a danger to life.

7. Can pregnant or breast-feeding women be vaccinated with COVID-19 vaccines?

Data on the use of COVID-19 vaccines during pregnancy and lactation are still very limited; however, laboratory studies on animal models have not shown harmful effects. In particular, the vaccines are not contraindicated and do not exclude a priori pregnant women from vaccination, in that pregnancy, especially if combined with other risk factors such as diabetes, cardiovascular disease and obesity, could make them more exposed to risk in case of severe COVID-19 disease. 
As for breastfeeding, despite the lack of specific studies, there is no biologically plausible risk preventing them from continuing breastfeeding. The Italian National Health Institute (Istituto Superiore di Sanità), through the ItOSS project, is participating in the national and international debate on these aspects and has recently published a document with the aim of supporting healthcare professionals, pregnant and breastfeeding women in the decision-making process regarding vaccination. As a rule, vaccination during pregnancy and breastfeeding should be decided in close consultation with a healthcare professional, after balancing benefits and risks.

8. Can women of childbearing age be vaccinated with COVID-19 vaccines?

Studies on animal models do not show any harmful effects on reproductive capacity associated with vaccination. Therefore, vaccination is also indicated in women of childbearing age.

9. Can children be vaccinated with COVID-19 vaccines?

The vaccines available are not currently authorised for people aged below 16 years (Comirnaty) and 18 years (Moderna, Vaxzevria and Janssen).

Conditions for vaccination

NB: For further indications on management of subjects with severe allergies, autoimmune diseases and immunodeficiencies, it is advisable to refer to the recommendations of the periodically updated Learned Societies.

1. Can people with chronic diseases, diabetes, cancers and cardiovascular diseases be vaccinated?

Since these people are most at risk of developing a serious condition in case of SARS-CoV-2 infection, it is important that they should be vaccinated.

2. Can people with respiratory allergies (rhinitis, conjunctivitis, bronchial asthma) be vaccinated?

People who suffer or have suffered from respiratory allergy can be vaccinated, remaining under observation, like everyone, for 15 minutes after the injection. Any ongoing antiallergic treatment, including specific immunotherapy, shall not be suspended. During specific immunotherapy, the vaccine should be administered with a 48 hours interval.

3. Can people with severe persistent bronchial asthma be vaccinated?

For those suffering from severe persistent bronchial asthma, well controlled by therapy, vaccination is recommended remaining under supervision for 60 minutes. In the case of uncontrolled asthma, the administration of the vaccine should be postponed until the clinical situation is again under control. If asthma cannot be controlled by therapy, the vaccine shall be administered in a protected environment (hospital), remaining under medical supervision for 60 minutes.

4. Can people with food allergies be vaccinated?

People with food allergies can be vaccinated by remaining under observation, like everyone, for 15 minutes after the injection. Should you have previously experienced severe allergic reactions (anaphylaxis) to food, you shall remain under medical supervision for 60 minutes.

5. Can people with allergies to drugs or to their excipients be vaccinated?

People with drug allergies can be vaccinated remaining under observation, like anyone else, for 15 minutes after the injection. Should you have previously experienced severe allergic reactions (anaphylaxis) to medicines, you shall remain under medical supervision for at least 60 minutes. People with suspected SERIOUS allergy to polyethylene glycol (PEG), macrogol and polysorbate excipients, shall be referred to an allergist before being administered the COVID-19 vaccine.

6. Can people with contact allergies (dermatitis) be vaccinated?

People having previously experienced contact dermatitis can be vaccinated.

7. Can people with latex allergies be vaccinated?

Yes, because all COVID-19 vaccines currently in use do not contain latex. However, it is necessary to inform the vaccination centre that you are allergic to latex so that the vaccination is carried out with latex free material. In case of severe allergic reaction (anaphylaxis) from latex the observation time after vaccination is extended to 60 minutes.

8. Can people with mastocytosis be vaccinated?

For vaccination of people with mastocytosis it is recommended, as with routine vaccines, oral anti-histamine coverage from 1 day before to 5 days after vaccination, and to remain under medical supervision for at least 60 minutes after the injection. In case of previous anaphylactic reactions to any or unknown substance, the vaccine should be administered in a protected environment (hospital).

9. Can people with celiac disease or organ-specific autoimmune diseases (e.g., Hashimoto's thyroiditis) be vaccinated?

People suffering from celiac disease or organ-specific autoimmune diseases can be vaccinated, as these diseases are not a contraindication to vaccination.

10. Can people with autoimmune diseases or documented immunodeficiency be vaccinated?

People with autoimmune diseases who have no contraindications can receive the vaccine. The ongoing therapy can be adjusted to the specialist’s indications. There are few data on use in immunocompromised people (i.e., whose immune system is weakened). Although these people may not respond as well to the vaccine, no particular safety concern is present. Immunocompromised people can be vaccinated since they may be at high risk for COVID-19 infection.

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