Virus Experts Are Sending This New Warning to Vaccinated People


COVID is on a decline in the U.S. these days, with the Centers for Disease Control and Prevention (CDC) reporting that infections have fallen by more than 28 percent in the last week and that hospitalizations are down by over 27 percent. But the pandemic is far from over, and virus experts have been cautioning that things could take a turn for the worst at any point—as we've seen time and again over the past two years. With the possibility of another wave on the horizon, many vaccinated people are now wondering it's time to get another booster shot. According to experts, that may not be the case.

RELATED: Pfizer's CEO Just Gave This New Warning to Fully Vaccinated People.

In a new interview with The Atlantic, John Wherry, PhD, an immunologist at the University of Pennsylvania, warned against getting a second booster before it's necessary—especially since there is only one kind of COVID vaccine available in the U.S. right now. According to Wherry, boosting too often with the original vaccine could cause your immune system to react to newer and more different variants like the Omicron variant with lower effectiveness.

Per The New York Times, many experts also share this concern of "original antigenic sin," which means that the immune system's response is so oriented to the first version of the virus (which the current vaccine was made for) that its response to emerging variants becomes less powerful.

Wherry told The Atlantic that he recommends waiting for an alternatively designed vaccine, such as a possible mucosal vaccine or Novavax's protein-based shot. "It doesn't make sense to keep boosting against a strain that's already gone," Ali Ellebedy, PhD, an immunologist at Washington University in St. Louis, told The New York Times in January. "If you are going to add one more dose after three, I would definitely wait."

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For its part, Pfizer seems to feel differently. According to The Washington Post, the pharmaceutical company just filed for emergency authorization of a second booster shot of their current COVID vaccine for people 65 and older on March 15. The newspaper reports that Pfizer's submission to the U.S. Food and Drug Administration (FDA) claims that booster immunity is already waning against severe illness for older adults and includes "real world data" collected in Israel—a country that has already authorized a second booster for this age group—that indicates a fourth shot could reverse this.

"We are working right now very intensively," Albert Bourla, CEO of Pfizer, said during a Washington Post Live event. "I think our data suggests that [fourth doses] are protecting—they are improving dramatically the protection, the fourth dose compared to the third for Omicron after some time, after, let's say, three to six months."

In The Atlantic, virus experts say that while giving a fourth shot right now when COVID infections are declining might provide older adults with more protection for some time, it could also jeopardize their protection later on if cases start to rise again. Some say it might need to be a case-by-case decision.

Lona Mody, MD, a geriatrician at the University of Michigan, told the news outlet that she doesn't believe there is enough data yet to give the green light for second boosters to all older adults. But she also said that if one of her patients felt they needed one given their living situation, their general health, or the level of exposure at their job, "I would definitely consider it."

RELATED: This Is How Long Your Booster Will Last, Study Says.