Americans marked a grim Christmas Eve on Thursday as coronavirus infections exploded nationwide, political leaders warned them not to travel or gather in large groups and a highly contagious variant of the virus spread further in Europe.
More than one million people have received the first of two vaccine doses since Dec. 14, according to the U.S. Centers for Disease Control and Prevention. But the vaccinations have so far had little effect on the latest surge in cases spiraling nationwide.
Achieving herd immunity against the virus could require vaccination of up to 90% of Americans, Dr. Anthony Fauci, the most prominent U.S. infectious disease expert, told the New York Times in an interview.
"We really don't know what the real number is. I think the real range is somewhere between 70 to 90 percent. But, I'm not going to say 90 percent," Fauci said,
Fauci, who is advising both Republican President Donald Trump and President-elect Joe Biden, a Democrat, on the pandemic, acknowledged that he had revised his estimates upward from earlier in the year when he said the nation would reach herd immunity by inoculating 60% to 70% of the population.
Fauci was vaccinated earlier this week on live television.
The United States recorded more than 3,000 deaths for the second consecutive day on Wednesday, according to a Reuters tally. The U.S. death toll since the pandemic broke out in March has surpassed 326,000.
The states of Tennessee and California have emerged as the epicenters of the latest surge
"Our state is ground zero for a surge in COVID-19 and we need Tennesseeans to their part," Tennessee Governor Bill Lee, a Republican, said in a tweet on Wednesday. Lee asked residents of the southern state to wear masks and avoid large gatherings over the holidays.
Tennessee has recorded 119 new cases per 100,000 people over the last seven days, according to data from the Centers for Disease Control. California, the nation's most populous state, stood second at 105 cases per 100,000 people. Rhode Island and Arizona have also seen recent spikes.
State and local political leaders nationwide have urged Americans not to travel for the holidays, saying that Thanksgiving celebrations had further spread the virus.
Many Americans, weary after more than nine months of lockdowns, have defied those warnings. More passengers flew on commercial flights on Wednesday than any other day of the pandemic, with 1,191,123 passengers passing through airport checkpoints, according to data from the U.S. Transportation Security Administration.
That number represents a drop from 2019, when 1,937,235 flew on Dec. 23.
Health care workers, elderly nursing home residents, elected officials, and firefighters are among those receiving the vaccines first. Most Americans have been told it could be six months or more before they are eligible for the shots.
Political leaders have come under criticism from both sides of the ideological spectrum for putting themselves at the front of the line.
Even as vaccination programs give Americans a reason to hope that control of the pandemic may be in sight, an even more transmissible variant has spread rapidly in the United Kingdom.
The mutant variant was found in Germany for the first time, the German state of Baden-Wuerttemberg said on Thursday.
The United States, unlike many nations worldwide, has not banned travelers from Britain but the governors of New York and Washington state have ordered travelers from the U.K. to quarantine on arrival.
New York, an early epicenter of the pandemic, has recorded more than 36,000 COVID deaths, far more than any other state.