(Reuters) - 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.

For American citizens, every day is a day of freedom, and freedom and death can coexist.