COVID Leaves This in Your Body Even If You're Asymptomatic, New Study Says

New research brings good news for asymptomatic COVID patients.

Over a year into the pandemic, you likely already know that recovering from a case of COVID typically confers some level of protection in the months following. Yet, as a team of French researchers from the Institut Pasteur and the Vaccine Research Institute (VRI) at University Paris-Est Créteil have pointed out, the exact nature of this protection has, until now, been "poorly characterized." They say that data has been especially lacking surrounding asymptomatic COVID cases, which they estimate may account for nearly half of all infections. Because of this, many patients who had mild COVID cases are in the dark as to whether they're protected after recovery.

That's why the team set out to shed light on the level of protection following infections without symptoms, sharing their findings in the journal Cell Reports Medicine last week. They confirmed that asymptomatic infections leave behind an important type of antibody—a finding that could change how we understand immunity in asymptomatic cases. Read on to find out what they discovered, and for more on protection against COVID, This One Vaccine May Protect You Against All Variants, New Study Says.

COVID infections leave behind "polyfunctional antibodies."

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According to the researchers, COVID infections leave "polyfunctional antibodies" in the body after recovery. They're called "polyfunctional" because they prevent reinfection using more than one method, explains Timothée Bruel, a co-author of the study and a scientist in the Institut Pasteur's Virus & Immunity Unit and at the VRI.

"This study demonstrated that individuals infected with SARS-CoV-2 have antibodies that are capable of attacking the virus in different ways," Bruel shared in a statement. He explained that these antibodies render viral particles no longer infectious in two ways. First, they prevent the virus from entering healthy cells (a process known as "neutralization"). Second, they activate cells known as "Natural Killer" or "NK" cells, which kill infected cells. And for more up-to-date COVID news delivered right to your inbox, sign up for our daily newsletter.

These antibodies are present in both symptomatic and asymptomatic cases.

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Until recently, there was little data on whether or not asymptomatic COVID infections could produce strong neutralizing antibodies. However, the French study found that polyfunctional antibodies both blocked cell entry and also killed infected cells, even in asymptomatic cases. The team concluded that both symptomatic and asymptomatic COVID cases "induce antibodies capable of killing infected cells regardless of the severity of the disease." And for more essential COVID news, You're More Likely to Get COVID After Vaccination If You're Over This Age.

Asymptomatic patients get nearly the same level of protection.

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The team also compared the strength of protection following asymptomatic and symptomatic cases. They discovered that the polyfunctional antibody levels were only "slightly lower" in asymptomatic cases.

"The study reveals new mechanisms of action of SARS-CoV-2 antibodies and suggests that the protection induced by an asymptomatic infection is very close to that observed after a symptomatic infection," explained Olivier Schwartz, a co-author of the study and scientist at the VRI, in a statement.

You'll get even stronger protection against COVID from the vaccine.

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While the study's findings are undoubtedly good news for anyone who's had an asymptomatic case of COVID, experts still say you should plan on getting vaccinated for long-lasting protection against the virus.

According to White House COVID Advisor Anthony Fauci, MD, becoming vaccinated after recovering from a natural infection will greatly increase the "durability" of protection. He emphasized that following a full regimen of either Pfizer or Moderna's vaccines can increase the level of neutralizing antibodies by tenfold upon the second dose. And for more on the vaccine, This Is the Only Way to Tell If Your COVID Vaccine Worked, Doctors Say.

Lauren Gray
Lauren Gray is a New York-based writer, editor, and consultant. Read more
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