This One Vaccine May Protect You Against All Variants, New Study Says

This is the only vaccine to be proven effective against new variants.

Last month, COVID numbers plateaued and then recently, they started to climb again in a dangerous trajectory that suggests we're far from out of the woods. Experts say that rising U.S. case counts are likely due to two things: relaxed restrictions and the presence of more contagious new variants from the U.K., Brazil, and South Africa. These strains add an unpredictable new element to the pandemic, which many medical professionals warn could thwart our efforts to reach herd immunity.

Yet there are many reasons to be cautiously optimistic about the pandemic's future, vaccines being chief among them. With three highly efficacious shots on the market, we now have a way to push back against these new COVID variants by slowing their spread. And while any of the current vaccines may be effective against emerging variants, only one company has formally assessed their own product and found it to be effective against these new threats. Read on to find out which vaccine was put to the test, and for more breaking vaccine news, check out Pfizer's Vaccine Protects You for at Least This Long, Study Finds.

Pfizer generates neutralizing antibodies against all variants.


A team of researchers from Pfizer and the University of Texas Medical Branch set out to answer the question of whether vaccines developed to fight older COVID variants would protect against newer strains. Ultimately publishing their results in the New England Journal of Medicine in March, they set up a lab trial to test antibodies in serum samples from 15 volunteers who had received both vaccine doses. Within this small sample, they found that the vaccine generated a "substantial" antibody response to lab-engineered versions of the virus variants.

"Taken together, these findings indicate that this vaccine is likely to be effective against the variants studied, although precisely how effective they are in the real world will require data on the vaccine's actual effect in populations, not just in laboratory studies such as this one," reports BBC Science Focus Magazine. Further studies are likely to look at other aspects of immune response, including T-cell (cellular) immunity, they explain. And for more COVID news delivered right to your inbox, sign up for our daily newsletter.

The Pfizer vaccine does protect against all variants, but not equally well.

Woman getting COVID vaccine

While Pfizer's vaccine appeared to protect against all of the new variants, the study found that it did so to varying degrees depending on variant type. The team discovered that the shot was most protective against the original strain and the B.1.1.7 variant first detected in the U.K., while eliciting a slightly lower response against the P.1 variant from Brazil. The Pfizer vaccine was found to be least against the B.1.351 variant first identified in South Africa.

"Reassuringly, while the levels were lower for the [Brazilian and South African] variants, they were still substantial, and likely to indicate that the vaccine will be effective," Peter English, MD, a consultant in communicable disease control, told Science Focus. And for more on how the Pfizer shot is performing, check out The Pfizer Vaccine Is 100 Percent Effective for People This Age, Study Says.

Updated trial data suggests slightly lower overall efficacy.


As Reuters reports, Pfizer announced a Phase 3 update to its trial data on April 1: their two-dose vaccine is now considered 91 percent effective, a slightly lower overall efficacy rate than previously announced.

The additional data came from 12,000 individuals who had been inoculated for at least six months, as well as "a small subset of study volunteers in South Africa," where the B.1.351 variant is prevalent. While at face value, this may seem to tarnish the results from the initial 44,000 volunteer trial, this news actually confirms that the Pfizer vaccine offers potent protection in an increasingly complicated pandemic landscape.

And for more on how Pfizer is affecting patients, check out The One Side Effect That's Much More Common With Pfizer, Data Shows.

We may still need booster shots.

doctor giving young man a covid vaccine

Though the current Pfizer vaccine appears to offer significant protection against COVID variants, the company reiterated recently that they are still anticipating a need for both booster shots and an upgraded vaccine.

On Feb. 25, the pharmaceutical company announced that they would begin evaluating booster shots in relation to new variants. "We want to be prepared for different scenarios," Ugur Sahin, CEO and Co-founder of BioNTech, which co-created the Pfizer vaccine, said in the announcement. "Therefore, we will be evaluating a second booster in the current regimen as well as preparing for a potential rapid adaption of the vaccine to address new variants which might escape the current version of our mRNA-based vaccine." And for more on the Pfizer vaccine's efficacy, check out  The Pfizer Vaccine May Be Less Effective If You Have This Common Condition.

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