Pfizer seeks approval for third vaccine dose

A booster shot might increase immunity against the delta variant of the coronavirus, the company said on Thursday. But the U.S. Food and Drug Administration and Centers for Disease Control and Prevention responded the same day that fully vaccinated Americans do not need further shots. Pfizer and BioNTech started creating a trial batch of boosters, and Pfizer plans to ask the FDA for emergency approval in August for a third dose.

What’s changed? Pfizer noted an Israeli study found that its two-shot vaccine was only 64 percent effective against the delta variant. A French journal reported on Thursday that the delta variant’s spike protein makes it harder for antibodies to attack. But other studies have shown that two shots of mRNA vaccines like Pfizer’s were 95 percent effective at preventing hospitalization with COVID-19. Delta is on track to become the globally dominant variant.

Dig deeper: Listen to Jill Nelson’s report in The World and Everything in It about Israel’s vaccine drive.