Biden administration health officials increasingly think that vulnerable populations will need booster shots even as research continues into how long the coronavirus vaccines remain effective.

Senior officials now say they expect that people who are 65 and older or who have compromised immune systems will most likely need a third shot from Pfizer-BioNTech or Moderna, two vaccines based on the same technology that have been used to inoculate the vast majority of Americans thus far. That is a sharp shift from just a few weeks ago, when the administration said it thought there was not enough evidence to back boosters yet.

On Thursday, a key official at the Centers for Disease Control and Prevention said the agency is exploring options to give patients with compromised immune systems third doses even before regulators broaden the emergency use authorization for coronavirus vaccines, a step that could come soon for the Pfizer vaccine.

Dr. Amanda Cohn, the chief medical officer of the C.D.C.’s immunizations division, told an advisory committee to the agency that officials were “actively looking into ways” to provide certain people access to booster shots “earlier than any potential change in regulatory decisions.”... Read More: NY Times