COVID-19
Imagine there are two people you know. One got sick with COVID-19, had some symptoms, and has now recovered. The other was not sickened, but was able to receive both doses of their COVID-19 vaccine.
Both of these people now have the ability to fight off a COVID-19 infection in their body. But is one better protected than the other? Maryrose Laguio-Vila, MD, an infectious disease specialist with Rochester Regional Health has some insights into that debate.
First, it can be helpful to understand how your body fights a COVID-19 infection.
When COVID-19 virus particles enter a person’s body, their immune system recognizes the particles as something that does not belong there. That triggers a response that causes your body’s immune cells to attack the particles that do not belong there.
Once your body encounters an infection once, it will remember how to fight against that type of infection again.
There are several ways that a person’s body can become protected against infections such as COVID-19. Two of those are infection-acquired immunity and vaccine-acquired immunity.
Infection-acquired immunity happens when your body is attacked by a virus, bacteria, or other foreign substance. Once your body identifies the pathogens causing the illness, it will create proteins called antibodies to attack those pathogens. Your body then stores information about how that pathogen works and how to fight it – just in case there’s a next time.
Vaccine-acquired immunity is a similar process, except your body does not need to become infected to learn how to fight against the pathogens.
With the COVID-19 vaccine, it contains a code that sends instructions to your body’s immune system. Those instructions will tell your body what to do when a specific pathogen – such as COVID-19 – shows up and how to fight it. That way, your immune system is already prepared – just in case.
“None of the COVID-19 vaccines have any live version of the virus in them,” Dr. Laguio-Vila said. “This is a safe way of helping your body learn to fight COVID without being sickened by it.”
The CDC recently published research about this topic based on a study of a community in Kentucky. The study looked at people ages 18 and older who tested positive for COVID-19 from March to December 2020.
That group was analyzed again between May 1 – June 30, 2021 to see if they had a positive NAAT or antigen test for a second time. The results showed those who were not vaccinated after their first infection were more than twice as likely to be infected with COVID-19 a second time as compared to those who were subsequently fully vaccinated afterwards.
Another factor is how “the emergence of new variants might affect the duration of infection-acquired immunity,” according to the CDC. Just because your immune system beat a COVID infection once doesn’t mean it will be able to bear a variant COVID infection such as the Delta variant.
Based on all of this, getting fully vaccinated – even if you have already tested positive for COVID-19 – is a way to obtain additional protection against re-infection.
