Moderna president: 4th vaccine dose only necessary for certain groups

• "Variants are coming and Omicron was the first one...but also we know that the duration of the protection doesn't last very long," Bourla said.

State of play: Fourth doses are already authorized for some immunocompromised people.

What they're saying: "For those who are immune-compromised, those who are older adults, over the age of 50 or at least 65, we want to strongly recommend and encourage [a fourth shot], the same way we do with flu vaccines," Hoge said.

• But Hoge stopped short of recommending fourth doses of the vaccine for the general public and said he doesn't expect "any kind of recommendations that would be across the board for everyone."
• "Whether or not public health continues to recommend it for everybody is a more complicated thing, because not everybody's wanting to get the first couple ones."

The bottom line: "Is it necessary? I think that's a strong word. I think it will provide a benefit to anyone who gets it," Hoge said.

• "I personally will get a booster every year because I don't want to ever lose my sense of smell," he said, adding, "Long COVID sounds nasty."