How do COVID-19 vaccines work?
In general, vaccines act by simulating infectious agents (viruses, bacteria or other microorganisms). This "primes" our immune system to respond quickly and effectively, when actually exposed to the pathogen.
Traditionally, vaccines did this by introducing an attenuated form of an infectious agent so that our immune system generates a memory of it. Some of the vaccines for COVID-19 have been designed this way.
Other COVID-19 vaccines have been designed with new methods: For example, messenger RNA vaccines. Instead of introducing antigens (substances that make the immune system produce antibodies), these vaccines introduce the genetic code into our body so that our immune system produces the antigen on its own. It is important to note that this mRNA vaccine technology has been studied for several decades.
They do not contain any live viruses and do not interfere with human DNA. There are other Vaccines Using Viral Vectors: The vector (a harmless virus, not COVID-19) enters a cell within our body and uses our cellular machinery to produce a harmless portion of the virus that causes COVID-19 (Spike protein). Then our cell unfolds the Spike protein on its surface, and our immune system recognizes that it does not belong to us. This triggers the response of our immune system, which begins to produce antibodies and activate other immune cells to fight what it considers an infection. In this way, our body will have learned how to protect ourselves from a future COVID-19 infection.
Do vaccines for COVID-19 contain dangerous substances?
The ingredients in the vaccine vary by manufacturer, but none of the vaccines contain eggs, gelatin, latex, or preservatives. All COVID-19 vaccines are free of metals such as iron, nickel, cobalt, lithium, and rare earth alloys. It is important to mention that they are also free of created products such as microelectronics, electrodes, carbon nanotubes or nanowire semiconductors.
Should I get vaccinated if I already got COVID-19?
Yes, you should get vaccinated even if you have already had COVID-19, mainly for two reasons:
To date, investigations have not yet shown how long a person is protected from COVID-19 after recovering from a COVID-19 infection.
Vaccination will protect you even if you have already had COVID-19.
There is evidence that people may gain better protection from being fully vaccinated than from having COVID-19. Unvaccinated people who have already had COVID-19 have been reported to be more than twice as likely to get COVID-19 again compared to fully vaccinated people.
Is it recommended to vaccinate pregnant women against COVID-19?
Yes, it is recommended to vaccinate against COVID-19 for all people over 12 years of age, including pregnant women, women who are breastfeeding, women who are trying to become pregnant or who plan to do so in the future. This is only a recommendation, so it is best to consult your gynecologist before deciding to get vaccinated.
How long is the protection of the vaccine for COVID-19?
It is not known how long protection lasts in people who get vaccinated. What is known is that having the vaccine offers much more security than not having it since there are very serious cases and deaths from COVID-19 and if you contract COVID-19, you also run the risk of infecting your loved ones, who could get seriously ill. Vaccine studies are currently underway to be more certain of how long the protection might last. It is recommended that some people with suppressed immune systems get an extra dose of the COVID-19 mRNA vaccine after the initial 2 doses.
How many doses do I need to have protection?
The number of doses needed depends on the vaccine you receive. For optimal protection:
Pfizer-BioNTech: two doses 21 days apart.
Moderna: two doses 28 days apart.
Janssen / Johnson & Johnson: single dose.
Sinopharm: two doses 21 days apart.
Can I get vaccinated outside the recommended interval?
If you receive a two-dose vaccine, the second dose should be given as close to the recommended interval as possible. However, the second dose may be given up to 42 days after the first dose, only if necessary. The second dose should not be received before the recommended interval.
Is there interchangeability?
People who start a series with a specific vaccine must complete the series with the same product. There are no data to date that support the interchangeability between the different vaccines available.
If I have already been vaccinated abroad, can I get vaccinated again here?
There is no solid evidence to date that there is any benefit in adding vaccines, nor is there evidence that it is negative or unsafe. However, it is better to consider that more people reach the status of vaccinated to achieve greater global protection and try to cut the chain of infection.
Can people with other illnesses get the COVID-19 vaccine?
People with underlying conditions can be vaccinated against COVID-19, as long as they have not had severe or immediate allergic reactions to any COVID-19 vaccine or any of the ingredients in the vaccine. Vaccination is even more important for adults of any age with certain underlying conditions because they are at higher risk of becoming seriously ill from COVID-19.
Can I get vaccinated if I currently have COVID-19?
No. Symptomatic people with COVID-19 should wait to be vaccinated until they have recovered from the disease and until they meet the conditions to suspend isolation; People without symptoms should also wait until they meet the criteria to get vaccinated. This also applies to people who become ill with COVID-19 between the first and second doses of the vaccine.
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