The influenza vaccine protects against different types of influenza virus responsible for the development of influenza. However, as this virus undergoes many mutations over time, it is becoming increasingly resistant and therefore the vaccine needs to be redone every year to protect people vaccinated against new mutations of the virus.
Generally, the vaccine is given through an injection into the arm and helps the body develop immunity against the flu, preventing the onset of flu-related complications such as pneumonia or heart problems, as well as hospitalization and death. For this, the vaccine exposes the person to a small dose of the inactivated influenza virus, which is enough to "train" the defense system to defend itself if it ever becomes in contact with a live virus.
The price of the flu vaccine varies from $ 100 to $ 200 in private clinics, but can also be made free of charge in the SUS by people who belong to the flu risk groups.
1. Which risk groups should take the vaccine?
The vaccine is indicated for people at higher risk of catching the flu virus, such as:
- Children between 6 months and 5 years;
- People over 60;
- Pregnant women;
- Women in postpartum up to 45 days;
- Health 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 patients, 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 due to the conditions of the place where they are, which facilitates the transmission of diseases.
2. Does the flu vaccine protect against H1N1?
The flu vaccine protects against different groups of the flu virus, including H1N1. In the case of vaccines administered free of charge by SUS, they protect against 3 types of the virus, influenza A (H1N1), A (H3N2) and Influeza type B, being known as trivalent.
The vaccine, which can be bought and administered in private clinics, is usually tetravalent, also protecting against another type of Influeza B.
3. Where can the vaccine be administered?
The influenza vaccine offered by the SUS to risk groups is usually administered at health centers 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.
4. Is it necessary to take the vaccine every year?
The flu vaccine lasts for 6 to 12 months and therefore must be given every year, especially in the fall. In addition, since influenza viruses are rapidly mutated, the new vaccine serves to ensure that the body is protected against new types that have come up throughout the year.
After the flu shot gets started in 2 to 4 weeks, it is not able to stop a developing flu.
5. Is it possible to take the flu shot?
Ideally the vaccine should be done up to 4 weeks before the onset of any flu symptom. However, if the person is already infected, it is advisable to wait until the symptoms disappear before vaccination, to avoid that the natural symptoms of influenza are confused with a reaction to the vaccine, for example.
Vaccination will protect the body against another possible infection with the flu virus.
6. What are the risks of the flu vaccine?
Some side effects that may arise after the vaccine application include the development of cold symptoms such as chills or runny nose. In addition, a reaction at the site of the bite may also develop such as pain, swelling and redness. In this case, it is recommended to apply a pebble of ice on the spot for a few minutes throughout the day in order to reduce swelling.
In rare cases, headache, tiredness, muscle pain, unusual weakness or feeling in the arms and legs, high fever and abnormal bleeding may still occur.
7. Who should not take the vaccine?
This vaccine is contraindicated for people with bleeding, guillain-barré syndrome, blood clotting problems such as haemophilia or purple spots on the skin that arise easily, neurological disorder or brain disease.
In addition, it should also not be applied in people with egg allergy or latex, weakened immune system, as in the case of cancer treatments or if you are taking anticoagulant medicines, as well as during pregnancy and lactation.
8. Can pregnant women take the flu vaccine?
During pregnancy the woman's body becomes more vulnerable to infections and therefore there are high chances of catching the flu. Thus, the pregnant woman is part of the groups at risk for influenza and, therefore, must vaccinate for free at the SUS health posts.
