WATCH: White House Covid-19 task force briefing

WASHINGTON, DC -- The United States is facing a Covid-19 surge this summer as the more contagious delta variant spreads.

More than 629,000 Americans have died from Covid-19 while over 4.4 million people have died from the disease worldwide, according to real-time data compiled by the Center for Systems Science and Engineering at Johns Hopkins University.

Just 60.2% of Americans ages 12 and up are fully vaccinated against Covid-19, according to data from the Centers for Disease Control and Prevention.

The government's top infectious diseases expert, Dr. Anthony Fauci, said the crisis won't be under control until spring of next year -- and even then, it will need most American vaccine skeptics to change their minds -- came as a severe jolt to a weary nation.

"If we can get through this winter and get really the majority -- overwhelming majority -- of the 90 million people who have not been vaccinated, vaccinated, I hope we can start to get some good control in the spring of 2022," Fauci said.

"As we get into the spring, we could start getting back to a degree of normality, namely reassuming the things that we were hoping we could do -- restaurants, theaters, that kind of thing," Fauci added.