One of the biggest questions this afternoon about the COVID-19 pandemic has been why the virus kills some people and leaves others without detecting symptoms. Now, six months into the pandemic, we are finally getting some answers. According to Anthony Fauci, MD, director of the National Institute for Allergy and Infectious Diseases (NIAID), if you’re one who is known to get the common cold year after year, you may have some protection against the new coronavirus, thanks to the T cells in your immune system.
“If you look at [your immune system] metaphorically as an army with varying levels of defense, the antibodies prevent the virus from entering. That’s something like the first line of defense, “Fauci McClatchy said in a recent interview. For those viruses that escape and infect some cells, the T cells come in and kill the cells that are infected or block them. “
Fauci said much of the COVID research was “entirely exclusively focused on the antibody test,” but, he said, T cells are an “equally important component of the immune system.”
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Because COVID-19 is a new coronavirus, it was initially believed that your T cells could not detect it. It was assumed that T cells would only be found in people who already have COVID-19. But a new NIAID study published in the journal Science on August 4, suggests that up to 50 percent of people who are not exposed to the coronavirus need the T cells to fight the virus. Neither was a German study published in the journal Nature at the end of July looked at 68 healthy people who had not yet been exposed to the coronavirus. Among them, 35 percent needed the T cells in their blood to attack the new coronavirus.
As a result of this new study, experts believe that healthy individuals may have generated these T cells in combating similar infections of related coronaviruses in the past, such as the common cold. And the recently an individual was infected with another type of coronavirus, the greater the chance that they have something protection against COVID-19, Fauci told McClatchy.
“It’s kind of a punch of two,” he said. “It’s thought that the T cells that made you react a few years ago – three, four, five years ago – when you were exposed to a relatively benign coronavirus that caused the cold, could actually surround , and when you are exposed to the SARS Coronavirus-2, you may have some protection, “he said.
Serving as a secondary line of defense in the immune system Once antibodies have failed or disappeared, T cells also last much longer than antibodies. So, if you have read those striking reports that antibodies do not last – like a July study from the UK that found that COVID antibodies were rejected after only three weeks from the onset of infection – do not worry. These reports ignore the role of T cells, according to Fauci and other experts, which is just as pivotal.
Amesh Adalja, MD, senior scientist at the Johns Hopkins University Center for Health Security, told CNN that pre-existing T cells can also help us understand why COVID affects people so differently.
“If you can compare people with bad and mild illness and try to look at the T cells in those individuals and say, ‘Are people who have serious illness less likely to have cross-reactive T cells against people who “Mild disease may have more? cross-reactive T cells?” I think there is biological plausibility to that hypothesis, “he said. “However, it is clear that the presence of the T cell does not prevent people from becoming infected, but does it modulate the severity of infection? That is what seems to be the case.” And for more on this, check out This Is Why COVID Kills Some People and Others Are Symptom-Free, Says Study.
