Leading US epidemiologist Fauci said the country could achieve "public immunity" in late spring or early summer in 2021.

"The bottom line is, when do you vaccinate the majority of the population so that you can achieve community immunity? I believe that if we work effectively and convince people to vaccinate, we can

Fauci once said that it is necessary to vaccinate about 75-80% of the population in order to achieve community immunity across the country.

America's top epidemiologist also hopes that people's lives can gradually return to normal in the fall after widespread vaccination.

The United States on December 11 approved urgent approval of Pfizer's Covid-19 vaccine in the context of constantly rising numbers of nCoV infections and deaths, while treatment hospitals fell into overload.

The first doses of the Pfizer-BioNTech vaccine were shipped to 145 locations across the US on December 14.

A source familiar with the news on December 14 revealed that President Trump, Vice President Pence and other top US officials are about to get the Covid-19 vaccine.

Covid-19 appeared in more than 210 countries and territories, causing more than 73.2 million people to become infected and more than 1.6 million to die.