The common cold may protect you from severe COVID-19 symptoms, study says. Here’s why
If you’ve ever had the common cold, the cells in your immune system might be able to recognize those of the novel coronavirus, meaning you might have better protection against the disease it causes if infected.
Scientists behind the finding say this “memory” of viruses past could explain why some people are only slightly affected by COVID-19, while others get severely sick. The results were published Tuesday in the journal Science.
“We knew there was pre-existing reactivity, and this study provides very strong direct molecular evidence that memory T cells can ‘see’ sequences that are very similar between common cold coronaviruses and SARS-CoV-2,” Dr. Alessandro Sette, professor and member of the La Jolla Institute’s Infectious Disease and Vaccine Center in California, said in a news release.
“Immune reactivity may translate to different degrees of protection,” Sette said in the release. “Having a strong T cell response, or a better T cell response may give you the opportunity to mount a much quicker and stronger response” against COVID-19.
The new research builds upon a previous paper from the same institute that showed 40% to 60% of people from all over the world had cells in their immune system that reacted to SARS-CoV-2 despite never being exposed to it. Knowing this, the team set out to test the finding in a lab.
They studied blood samples that were collected between 2015 and 2018 from healthy individuals who have had the common cold and isolated their T cells, or cells that help the immune system fight infection, according to the study. The researchers learned of 142 different spots on the coronavirus that these T cells recognize.
About half of these spots were located on the virus’ spike protein — the part it uses to enter human cells. What’s more, these same T cells also recognized four types of common cold coronaviruses that share similar genetic fragments with SARS-CoV-2.
This, researchers say, suggests that fighting the common cold can teach your body to recognize and protect — to some degree — against COVID-19 if exposed; the lesson could determine how severe your case may be. However, the team notes, “this is speculation and much more data is needed.”
The T cells were also found on other parts of the coronavirus, which is good news for vaccines, according to the researchers. Vaccines usually target the part of the virus that allows the pathogen to enter human cells, but additional targets “could further enhance vaccine potency.”
