United Nation healthcare workers among others recommended for the nation's first COVID-19 inoculations could initiate getting shots within a day or two of regulatory consent next month, a top official of the government's vaccine development effort said on Sunday.

As per Dr. Moncef Slaoui, chief scientific adviser for Operation Warp Speed, some 70 percent of the US population of 330 million would need to be inoculated to achieve herd immunity from the virus, an ambition the country could achieve by May. It adds,  the U.S. Food and Drug Administration (FDA) would likely grant approval in mid-December for distribution of the vaccine produced by Pfizer Inc and German partner BioNTech, launching the largest inoculation campaign in U.S. history. The FDA's outside advisers are scheduled to meet on December 10 to review Pfizer's emergency-use application for its vaccine, which the company said was found to be 95 percent effective against infection from the highly contagious respiratory virus.

A second pharmaceutical company, Moderna Inc, is expected to seek separate consent later in December for its coronavirus vaccine. Appearing on several network news shows on Sunday morning, Slaoui sketched out a timeline for getting the initial doses of the Pfizer vaccine from FDA authorization into the arms of those who will be first in line to receive it.

Within 24 hours from the approval, the vaccine will be moving and located in the areas where each state will have told us where they want the vaccine doses," Slaoui told NBC's Meet the Press. So I would expect, maybe on day two after approval on the 11th or 12th of December, hopefully, the first people will be immunized across the United States, he said.

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