In an interview on Sunday with CBS’ “Face the Nation,” however, Pfizer CEO Albert Bourla didn’t specify which age groups he thinks will need a fourth shot — which raised plenty of eyebrows.

“We know that the duration of the protection doesn’t last very long,” Bourla said. “It is necessary, a fourth booster right now.”

He added that protection from the third shot is “quite good” against hospitalizations and deaths, but “not that good” against infections, and that protection against infection fades relatively quickly.

The other side: “Pfizer seems to be saying that, because their vaccine isn’t very good, people need more of it. If FDA approves another dose it would make sense to use a stronger vaccine instead, like Moderna or eventually Novavax,” said Cornell virologist John Moore.