False myths about flu and COVID-19 vaccines
Rumors and realities: what does science really say about vaccination?
In the information age, half-truths and rumors also abound. Social media and messaging apps have become spaces where scientifically unfounded claims about vaccines circulate. But behind every myth lies an explanation that science has long since debunked. That's why the Department of Health insists: being well-informed is just as important as getting vaccinated.
"The vaccine causes the disease"
One of the most widespread myths. Flu and COVID-19 vaccines activate the immune system so it learns to recognize and defend itself against the actual viruses without causing illness. The result: a faster and more effective immune response when there is contact with the virus.
"If you are in good health, you don't need to get vaccinated."
Being healthy doesn't mean being protected. Anyone, even in good health, can contract the flu or COVID-19 with complications—such as pneumonia or worsening of a chronic illness—or unknowingly infect vulnerable people. Vaccination protects those most at risk of serious consequences.
"Vaccines are not effective"
The data speaks for itself: according to the Department of Health, three out of four people admitted to ICUs with the flu were unvaccinated. Vaccines significantly reduce the risk of severe illness, hospitalization, and death. They don't completely eliminate the risk of infection, but they can turn a potentially serious illness into a mild or moderate case.
"You only need to get vaccinated once, and that's it."
Flu and COVID-19 viruses mutate every season, which is why the composition of the vaccines is updated annually. Getting vaccinated every year is the only way to be truly protected, as the immune system needs to strengthen its response to the new variants.
"Pregnant women cannot be vaccinated"
Quite the opposite. Health authorities recommend vaccination against the flu and COVID-19 during pregnancy. Vaccination reduces the risk of infection and potential complications, as it provides protection to the pregnant woman, the newborn, and the infant during the first months of life through antibodies transmitted via the placenta and, in the case of the flu, also through breastfeeding.
"Only older people should be vaccinated"
Based on age, everyone over 60 years old, and in the case of the flu, children between 6 months and 4 years old inclusive, should be vaccinated. This also applies to all people with underlying health conditions, regardless of age, as they may experience complications from the illness.
"If I've already had the disease, there's no need to get vaccinated."
Having had the flu or COVID-19 does not guarantee lasting protection. Natural antibodies decrease over time, and viruses mutate. That's why getting vaccinated after having had the illness strengthens immunity and reduces the risk of reinfection or complications.
"Vaccines are dangerous"
The danger lies in misinformation. Vaccines undergo rigorous testing before reaching the public and are constantly reviewed by agencies such as the European Medicines Agency (EMA). Serious adverse effects are very rare, while the benefit—preventing hospitalizations and deaths—is immense.
"Vaccines have long-term adverse effects"
There is no scientific evidence that vaccines cause long-term negative effects. Possible adverse effects are usually mild and short-lived: pain or redness in the arm, fever, general malaise, or muscle pain. As Bellvitge Hospital points out, it is much more likely to suffer a serious complication from the disease itself than from the vaccine.
"People with egg allergies cannot be vaccinated."
Based on available evidence, people with a history of egg allergy can receive the flu vaccine. The precautions should be the same as with any other vaccine. In the event of allergic reactions, experienced personnel will administer the vaccine and monitor the patient for 30 minutes afterward.
To get vaccinated, make an appointment at My Health, at citasalud.gencat.cat or in your CAP.
