Italian Medicines Agency Agenzia Italiana del Farmaco

FAQ - COVID-19 vaccines

FAQ - COVID-19 vaccines


6 October 2021

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 persons residing or otherwise present on the Italian territory, with or without a residence permit or identity documents, including holders of the STP (Stranieri Temporaneamente Presenti) or ENI (European Non Iscritto) code, holders of the numerical tax code Codice Fiscale or those without one, holders of an expired health card and those who fall into 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?

In subjects who have had prior (symptomatic or asymptomatic) SARS-CoV-2 infection, the administration of a single dose of SARS-CoV-2/COVID-19 vaccine may be considered, provided that vaccination is carried out preferably within 6 months from the infection and no later than 12 months after its resolution.
Subjects with immunodeficiency conditions (either primary or secondary following pharmacological treatments) who have had a previous SARS-COV-2 infection are recommended to follow the planned vaccination schedule.

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 who have contracted a SARS-CoV-2 infection after being administered the first dose of a vaccine with a two-dose vaccine schedule, the following guidelines apply:

  • in case of confirmed infection (defined by the date of the first positive molecular test) within the fourteenth day from administration of the first dose of vaccine, the completion is recommended of the vaccination schedule with a second dose to be carried out within six months (180 days) from the documented infection (date of the first positive molecular test) (after this period of time, the vaccination schedule can still be completed, as soon as possible, with the second dose only);
  • in case of confirmed infection (defined by the date of the first positive molecular test) after the fourteenth day from the administration of the first dose of vaccine, the vaccination schedule is to be considered completed as the infection itself is equivalent to the administration of the second dose. However, the possible administration of a second dose is not contraindicated.

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 and adolescents be vaccinated with COVID-19 vaccines?

Currently, there are no vaccines authorised for children aged under 12 years.
Comirnaty was initially authorised for people aged 16 years and over. Subsequently, it was authorised also for adolescents aged 12-15 years. Similarly, Spikevax (Moderna) was initially authorised for people aged 18 years and over, and then it was authorised also for adolescents aged 12-17 years. 
The other available vaccines (Vaxzevria and Janssen) are not currently authorised for people aged under 18 years.

COVID-19 vaccination of adolescents aged 12 to 15 years

1. What is the therapeutic indication of Comirnaty and Spikevax in adolescents aged 12-17 years?

Comirnaty and Spikevax are indicated for the prevention of COVID-19 in individuals aged 12 years and older.
Following an in-depth assessment, the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) concluded that data on the use of Comirnaty and Spikevax in adolescents aged 12 to 17 years meet the established efficacy, safety and quality criteria. Therefore, the benefit/risk ratio is considered positive also for this age group. 

2. Who can benefit most from the vaccination?

Those girls and boys who, due to diseases or pre-existing conditions, have an increased risk of progressing to serious COVID-19, will benefit most from the vaccination. In addition, the extension of vaccination to this population could be used to create a potential barrier of protection around those who cannot be vaccinated or may have a suboptimal immune response to the vaccine.

3. Will vaccination in adolescents aged 12-17 years occur differently from people aged over 18 years?

No, the method for administering the vaccines does not differ among age groups. In adolescents aged 12-15 years, each dose of Comirnaty is 0.3 mL and the vaccination course consists of two intramuscular injections administered at least 3 weeks apart and no more than 6 weeks apart. Each dose of Spikevax is 0.5 mL and the vaccination course consists of two intramuscular injections administered at least 4 weeks apart and no more than 6 weeks apart.

4. Are there any contraindications to the vaccination?

Vaccination with Comirnaty and Spikevax is contraindicated in all people with hypersensitivity to the active substance or to any of the excipients contained in the medicinal product. 
The second dose of the vaccine should not be given to those people who have experienced anaphylaxis (serious allergic reaction) at the first dose of Comirnaty or Spikevax.

5. What precautions should be taken into account for vaccination?

Vaccination should be postponed in people suffering from acute serious/debilitating febrile illness or acute infection. The presence of a minor infection and/or low-grade fever should not delay vaccination. 
The vaccine should be given with caution in people suffering from thrombocytopenia or any coagulation disorder (such as haemophilia) because bleeding or bruising may occur following an intramuscular administration. 
The efficacy, safety and immunogenicity of the vaccine has not been assessed in immunocompromised people, including those receiving immunosuppressant therapy. The efficacy of the vaccines may be lower in immunosuppressed individuals.

6. When is maximum protection achieved after vaccination?

As with adults, for adolescents aged 12-15 years too it is necessary to wait until 7 days after the second dose of the vaccine.

7. What are the possible side effects for adolescents?

The safety profile of Comirnaty and Spikevax in adolescents was similar to that seen in young adults. The most frequent adverse reactions in adolescents were injection site pain, tiredness, headache, muscle and joint pain, chills and fever. Adverse reactions are usually mild or moderate in intensity and resolve within a few days after vaccination. 
In adolescents aged 12-17 years no new side effects were observed that had not been reported in older age groups.
The assessment of vaccine safety is carried out according to the usual pharmacovigilance activities.

8. Have pharmacovigilance activities shown any safety signals that may be relevant to this age group?

EMA’s Pharmacovigilance Risk Assessment Committee (PRAC) is assessing very rare events of myocarditis (inflammation of the heart muscle) and pericarditis (inflammation of the heart membranes) that occurred after the administration of the mRNA vaccine. 
Most of these events occurred in the two weeks following vaccination, more often after the second dose and in younger men. Following vaccination, any symptoms indicative of myocarditis or pericarditis should be monitored, shortness of breath, palpitations or chest pain. If these symptoms occur, immediate medical attention should be sought.

9. How was the efficacy of vaccines assessed in adolescents?

As for Comirnaty, efficacy was assessed by analysing SARS-CoV-2 neutralising antibody titers one month after administration of the second dose. This showed that the antibody response observed in the 12-15 age group was not inferior to that observed in the 16-25 age group.
Additionally, to assess the efficacy of Comirnaty in adolescents aged 12-15 without evidence of prior infection at baseline, the ability of the vaccine to prevent the first outbreak of COVID-19 from 7 days after the second dose was analysed. There were no cases among participants (n=1,005) who received the vaccine, whereas 16 cases were identified among those who received placebo (n=978).
As for Spikevax, efficacy was assessed by analysing SARS-CoV-2 neutralising antibody titers one month after administration of the second dose. Data showed that the antibody response observed in the 12-17 age group was not inferior to that observed in the 18-25 age group.
Additionally, to assess the efficacy of Spikevax in adolescents aged 12-17 years, a secondary efficacy analysis was performed in 3,181 participants who received 2 doses of either Spikevax (n=2,139) or placebo (n=1,042) and had a negative baseline prior infection. No symptomatic COVID-19 cases were identified in people who received Spikevax, whereas 4 symptomatic cases were identified in those who received placebo.

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.

Additional dose in people with organ transplantation or who are immunocompromised

1. Why is an additional dose of vaccine needed?

Available evidence shows that subjects who received a solid organ transplant or who are immunocompromised have a reduced antibody response after receiving a complete primary vaccination course (2 doses of Comirnaty, Spikevax, Vaxzevria and 1 dose of COVID-19 Vaccine Janssen).

In these people, who are considered particularly vulnerable because of the increased risk of serious disease, the additional dose of vaccine is intended to ensure a better immune response and thus increase protection against COVID-19.

2. What evidence supports the need for an additional dose in people with organ transplantation or who are immunocompromised?

Although still partial and mainly related to people with solid organ transplantation, data show a reduced antibody response in immunocompromised adults following a complete vaccination cycle compared to that observed in healthy adults.

Several clinical studies, mainly conducted in an academic setting and of a limited size, have shown that the administration of a third dose of mRNA vaccine in this population can significantly increase the antibody titre and the percentage of subjects with seroconversion.

3. Who should receive an additional dose as a priority?

An additional dose of COVID-19 vaccine for completing the vaccination cycle may be considered as a priority in adults and adolescents >12 years of age (Comirnaty) or >18 years of age (Spikevax) with clinically relevant immunocompromised conditions.
These include subject who have received solid organ transplants and subjects with comparable immunocompromised conditions based on clinical evaluation.

4. Which vaccines are used?

In all cases, the additional dose should be based on one of the two mRNA vaccines authorised in Italy (Comirnaty and Spikevax). This is even in case of a first vaccination with an adenoviral vaccine (Vaxzevria and COVID-19 Vaccine Janssen). In addition, if the same mRNA vaccine used for the first two doses is not available, an additional “heterologous” dose with a different type of mRNA vaccine may be used.

Based on current knowledge, the recommended dosage for the additional dose is equal to the dosage authorised for the primary cycle.

5. How long after the second dose should the additional dose be given?

In subjects undergoing organ transplantation or with immunocompromised conditions, the additional dose should be administered at least 28 days after the last dose of the primary vaccination cycle.

6. Is it safe to receive an additional dose of vaccine? Are there sufficient data that prove it?

Preliminary data on the tolerability of the third dose of an mRNA vaccine are based on small studies and show a safety profile similar to that observed after the first or second dose. This is both in terms of type and frequency of local (injection site pain and redness) and systemic (tiredness, headache, chills, muscle and joint pain, fever) undesirable events.

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