EXPLAINER: What do we know about booster shots for COVID-19?

By CARLA K. JOHNSON
AP Medical Writer

U.S. health officials may soon recommend COVID-19 booster shots for fully vaccinated Americans. While many details remain unclear, it’s common for protection from vaccines to decrease over time. Researchers have been monitoring the performance of the COVID-19 vaccines to see how long protection lasts and to understand when to recommend boosters. One possibility is that boosters would be recommended eight months after the second shot of the Pfizer or Moderna vaccine. The first people vaccinated in the U.S. would likely be first in line for boosters — health care workers, nursing home residents and other older Americans.