US health officials call for booster shots against COVID-19

U.S. health officials Wednesday announced plans to offer COVID-19 booster shots to all Americans to shore up their protection amid the surging delta variant and signs that the vaccines’ effectiveness is falling.

The plan, as outlined by the director of the Centers for Disease Control and Prevention and other top authorities, calls for an extra dose eight months after people get their second shot of the Pfizer or Moderna vaccine. The doses could begin the week of Sept. 20.