|Articles|February 20, 2021

Immunological Memory and the SARS-CoV-2 Virus

Author(s)Killian Meara

Immune memory is the basis for durable protective immunity after infections or vaccinations.

Nearly all survivors of the coronavirus disease 2019 (COVID-19) develop immune cells that are necessary to fight a future re-infection. It has been discovered that people who have had the virus have protective immunity against the deadly disease for months, potentially even years, after their infection.

A study published in the journal Science discovered that key players In the immune system responsible for fighting off the specific pathogens related to SARS-CoV-2 can last in an individual’s system for at least 8 months after the onset of symptoms.

In a discussion with paper authors Jennifer Dan and Daniela Weiskopf, they talk about why immune memory is important to understand and important findings from their study.

“We were able to basically look up to 8 months post infection since the pandemic started in March and figure out how common the immune response would be in the general population to see if anyone did get infected would they maintain some level of protection and that does have implications for the vaccine rollout that is underway today,” Dan said.

“The good thing to see was 8 months out we still saw more than 90% have at least 3 arms of the immune system, which means we are very likely to protect against reinfection,” Weiskopf said. “What we don’t know is what is the difference in the 10% that actually drop off after an infection.”


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