Influenza vaccine: who can take it, reações (and dúcommon lives)

2023 Author: Benjamin Dyson | [email protected]. Last modified: 2023-05-21 01:37

The flu vaccine protects against the different types of the Influenza virus, including the H3N2, which are responsible for the development of the flu. However, as these viruses undergo many mutations over time, they become increasingly resistant and, therefore, the vaccine needs to be updated every year to protect against new forms of the virus.

The vaccine is given through an injection in the arm and helps the body develop immunity against the flu, preventing the emergence of serious complications such as pneumonia and other respiratory problems, as well as hospitalization and death. For this, the vaccine exposes the person to a small dose of the inactivated flu virus, which is enough to "train" the defense system to defend itself if one day it comes into contact with a live virus.

The vaccine is made available free of charge by the Unified He alth System (SUS) for the entire population over 6 months of age, but it can also be found in private vaccination clinics.

1. Who should get the vaccine?

In 2021, the Ministry of He alth expanded the flu vaccination campaign to all ages, including babies and children over the age of 6 months.

Previously, the flu shot was mainly advised for people who were more likely to come into contact with the flu virus or to develop severe symptoms and/or complications, such as:

• Children between 6 months and 6 years old (5 years and 11 months);
• Adults aged between 55 and 59;
• Older people over 60 years old;
• Pregnant women;
• Postpartum women up to 45 days;
• He althcare professionals;
• Teachers;
• Indigenous population;
• People with compromised immune systems, such as HIV or cancer;
• People with chronic illness such as diabetes, bronchitis or asthma;
• Trisomy carriers, such as Down syndrome;
• Adolescents living in socio-educational institutions.

In addition, prisoners and other persons deprived of their liberty must also be vaccinated, especially given the conditions of the place where they are, which facilitates the transmission of diseases.

2. Does the vaccine protect against H3N2, H1N1 or COVID?

The flu vaccine administered by SUS protects against 3 types of the Influenza virus: influenza A (H1N1), A (H3N2) and type B influenza, being known as trivalent. The vaccine that can be purchased and administered in private clinics is usually tetravalent, also protecting against another type of Influenza B virus.

In any case, the vaccine does not protect against any type of coronavirus, including the one that causes the COVID-19 infection.

3. Can I get the flu and COVID vaccine together?

The Brazilian Ministry of He alth indicates that the flu and COVID-19 vaccine can be applied on the same day, as long as they are in different muscle groups, with no interference in the effectiveness of the vaccines. If the vaccines are applied to the same muscle group, the recommendation is that they are applied with a distance of 2.5 cm so that it is possible to differentiate the side effects, if they happen

4. Where can I get the vaccine?

The flu vaccine offered by SUS to risk groups is usually administered at he alth posts, during vaccination campaigns. However, this vaccine can also be done by those who are not part of the risk group, in private clinics, after payment of the vaccine.

5. Is it necessary to take it every year?

The flu vaccine has a duration that can vary between 6 to 12 months and, therefore, should be given every year, especially during the autumn. In addition, as flu viruses mutate rapidly, the new vaccine serves to ensure that the body is protected against the new types that have emerged throughout the year.

After administration, the flu vaccine starts to take effect in 2 to 4 weeks and, therefore, is not able to prevent a flu that is already developing.

6. Can I get the flu shot?

Ideally the vaccine should be given up to 4 weeks before any flu symptoms appear. However, if the person already has the flu, it is advisable to wait for the symptoms to disappear before vaccinating, to avoid that the natural symptoms of the flu are confused with a reaction to the vaccine, for example.

Vaccination will protect the body against another possible infection with the flu virus.

7. What are the most common adverse reactions?

The most common adverse reactions after application of the vaccine include:

Headache, muscles or joints

Some people may experience fatigue, body aches, and headache, which may appear about 6 to 12 hours after vaccination.

What to do: rest and drink plenty of fluids. If the pain is severe, analgesics such as paracetamol or dipyrone can be taken, as long as they are prescribed by a doctor.

Fever, chills and excessive sweating

Some people may also experience fever, chills and sweat more than usual after vaccination, but these are usually transient symptoms, appearing 6 to 12 hours after vaccination, and disappearing in about 2 days.

What to do: if they cause a lot of discomfort, you can take analgesics and antipyretics, such as paracetamol or dipyrone, as long as they are guided by a doctor.

Reactions at the site of administration

Another of the most common adverse reactions is the appearance of changes at the injection site, such as pain, redness, hardening or slight swelling.

What to do: you can apply a little ice to the area protected with a clean cloth. However, if there are very extensive injuries or limitation of movement, you should go to the doctor immediately.

8. Who should not get the vaccine?

The flu vaccine is contraindicated for people with an egg or latex allergy, as well as for people who have had a severe allergic reaction to a previous dose of the vaccine. In any case, whenever there is any doubt about vaccination, it is recommended to consult a doctor.

9. Can pregnant women get the flu vaccine?

During pregnancy, a woman's body is more vulnerable to infections and, therefore, there is a high chance of catching the flu. Thus, pregnant women are part of the risk groups for flu and, therefore, should be vaccinated free of charge at SUS he alth centers.