e of the U.S. and the rest of the world had gotten the initial round of shots. “If you want to stop hearing about the variant of the week,” said Jennifer Nuzzo, a Johns Hopkins University public health specialist, “we need to do more work to make sure all countries have more access to vaccines.
Here are some questions and answers about vaccine immunity and boosters.
WHAT’S PROMPTING ALL THE BOOSTER DEBATE?
U.S. health officials have long said that people one day might need a booster — after all, they do for many other vaccines. That’s why studies are underway to test different approaches: simple third doses, mix-and-match tests using a different brand for a third dose, or experimental boosters tweaked to better match different variants.
But last week, Pfizer and its German partner BioNTech announced that they plan to seek Food and Drug Administration authorization of a third dose in August because it could boost levels of virus-fighting antibodies, possibly helping ward off worrisome mutants.
The companies haven’t publicly released data, and U.S. health officials issued a sharp response that boosters aren’t yet needed and that the government, not vaccine makers, will decide if and when that changes.
The World Health Organization said Monday there is not enough evidence to show that third doses are needed. It said the low shots should be shared with poor countries instead of being used by rich countries as boosters.
WHAT’S THE EVIDENCE THAT VACCINE PROTECTION REMAINS STRONG?
An Associated Press analysis last month found nearly all COVID-19 deaths in the U.S. occur among the unvaccinated. Infections and hospitalizations have begun rising as the highly contagious delta variant spreads in the last few weeks. But the Centers for Disease Control and Prevention says the surges are driven by the least vaccinated parts of a country that has plenty of shots if people would only take them.
No vaccine is perfect, meaning fully vaccinated people occasionally will get infected, but those so-called breakthrough cases usually are mild. Officials monitoring the need for boosters are watching closely for any jumps in serious breakthrough infections. So far, the news is good: The people first in line for vaccines back in December and January don’t seem to be at higher risk for breakthrough infections than those vaccinated more recently, the CDC’s Dr. Jay Butler said Tuesday.