Moderna President Stephen Hoge said Wednesday Covid-19 booster shots targeting the omicron variant could be ready to present for U.S. authorization by March, though both he and federal infectious disease point man Dr. Anthony Fauci said they believe current vaccines will be effective against the new strain, with Fauci advising the public to get a booster now.

Moderna has begun to develop an omicron-specific booster, Hoge told Reuters, as well as a multi-valent vaccine targeting omicron and three other coronavirus variants, though that shot will take several more months.

The March target date is the earliest the omicron booster could be approved under the U.S. Food and Drug Administration’s current guidelines, though the company would manufacture the vaccine during testing.

Hoge said he thinks the existing vaccines “will be able to slow down, if not completely stop, the omicron variant.”

Fauci advised the public in a press conference Wednesday morning to “get boosted now,” as “we may not need a variant-specific boost,” though he said the Biden administration has been in contact with the pharmaceutical companies developing Covid-19 vaccines about the potential need for these boosters.