The Food and Drug Administration is expected as soon as today to authorize extra doses of coronavirus vaccines for patients with weakened immune systems, a move that could mean additional shots will be available for the vulnerable population as soon as this weekend.

Dr. Anthony Fauci, the chief medical advisor to President Biden says COVID-19 booster shots are needed for those who are immunocompromised and that the need is “so imminent that we get them boosted so that they would be in a protected zone.”

Fauci also mentions that it was “preferable that you go with the same brand,” when it comes to vaccine boosters. He added that “there will be guidance when that time occurs.”