Is it time to change the definition of “fully vaccinated”?

As more indoor venues require proof of vaccination for entrance and with winter — as well as omicron, a new covid variant — looming, scientists and public health officials are debating when it will be time to change the definition of “fully vaccinated” to include a booster shot.

It’s been more than six months since many Americans finished their vaccination course against covid; statistically, their immunity is waning.

At the same time, cases of infections with the omicron variant have been reported in at least five states, as of Friday. Omicron is distinguished by at least 50 mutations, some of which appear to be associated with increased transmissibility. The World Health Organization dubbed it a variant of concern on Nov. 26.

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