(The Center Square) – The Biden administration announced Wednesday that federal health experts now recommend vaccinated Americans receive a COVID booster shot.

The boosters will be widely distributed to the public after research indicated that the vaccine’s effectiveness declines over time.

"We are prepared to offer booster shots for all Americans beginning the week of September 20 and starting 8 months after an individual's second dose," the experts said in a joint statement. "At that time, the individuals who were fully vaccinated earliest in the vaccination rollout, including many health care providers, nursing home residents, and other seniors, will likely be eligible for a booster."

While officials said recipients of the Johnson & Johnson vaccine will likely need a booster as well, Wednesday’s booster recommendation applies to those who have had the Pfizer or Moderna vaccine.

"Administration of the J&J vaccine did not begin in the U.S. until March 2021, and we expect more data on J&J in the next few weeks," the statement said.

The new official guidance comes just weeks after the CDC changed federal guidance to recommend that even vaccinated individuals should wear masks in certain settings.

A litany of federal health officials, including U.S. Centers for Disease Control Director Rochelle Walensky, signed the statement, the latest update from federal health experts as the COVID guidance continues to evolve.

“We would also begin efforts to deliver booster shots directly to residents of long-term care facilities at that time, given the distribution of vaccines to this population early in the vaccine rollout and the continued increased risk that COVID-19 poses to them," the statement said.