Washington, Nov 18 : Amid fear of a Covid-19 resurgence in the upcoming winter season, more states in the US have started offering booster doses, according to reports.

California made the first move to expand access when public health officials quietly sent a letter to local health jurisdictions and vaccine providers on November 9 instructing them to trust patients to decide whether a booster is appropriate, Xinhua news agency reported on Thursday.

Within days, officials in Colorado, New Mexico, Arkansas, West Virginia and New York City endorsed boosters for all adults.

"More states and jurisdictions are expected to follow," The Washington Post said in a report on Tuesday.

"If you're in doubt and you meet the waiting period, just get a booster. Choose the side of greater protection," Democratic New Jersey Governor Phil Murphy was quoted as saying on Monday.

"With the holidays coming up, we need as many people boosted as possible. It's that simple."

The Food and Drug Administration (FDA) is aiming to authorise booster doses of Pfizer-BioNTech's coronavirus vaccine for all adults as early as Thursday.

A report in The New York Times said that the "move that would expand the number of Americans eligible for additional shots by tens of millions".

The Centers for Disease Control and Prevention's (CDC) independent committee of vaccine experts has scheduled a meeting for Friday to discuss data on the booster dose's efficacy and safety.

If both the FDA and the CDC sign off this week, they will have acted strikingly quickly, a little more than a week after Pfizer asked for authorization of boosters for everyone 18 and older.

Under that scenario, any adult who received a second dose of the vaccine at least six months earlier would be officially eligible to get a booster as soon as this weekend.

The FDA is reportedly expected to rule without consulting its own expert panel, which has met frequently during the pandemic to review vaccine data and make a recommendation ahead of a regulatory decision.

More US states offering boosters amid fear of winter surge