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Before the U.S. rollout of Covid-19 mRNA vaccines began two weeks ago, health officials vowed to have 20 million Americans vaccinated by the end of the year. Their estimates were way off.

With only two days left in the year, Operation Warp Speed has missed its goal by a mile.

Less than 2 million Americans received the first (possibly placebo) dose of the mRNA vaccine. The numbers are a major disappointment to Dr. Anthony Fauci, who suggested that there must be some undercounting going on.

"We certainly are not at the numbers that we wanted to be at the end of December," Fauci told CNN's New Day.

"I mean, even if... 2 million is an undercount, how much undercount could it be? So, we are below where we want to be."

Fauci said he hoped to see "an increase in momentum" of vaccines going into people's arms in January, "because we really want to get those priority people vaccinated so that we can then get to what we call open season for the general population."

Fauci, who earlier admitted he lied about the percentage of herd immunity required to return the country to normal, now says 75-80% herd immunity is required.

Officials with the World Health Organization (WHO) advised that the vaccines do not prevent or slow the transmission of the virus. The official said masks, social distancing and quarantine will still be required even for those who get the vaccines.

During the 2009 H1N1 influenza outbreak, Fauci said healthy people shouldn't wear masks because masks create the perfect environment to grow bacteria and viruses.