Biden says companies spend a lot of time testing the safety of Covid-19 vaccines and asserting that the products are safe.

"Safe vaccines. Please for yourself, your family, your community and this country, get vaccines when it becomes available and your turn. That's how we beat this pandemic," said US President Joe Biden.

Many Americans are skeptical of the rapidly evolving vaccines to deal with the global health crisis.

The US President said the program to get the Covid-19 vaccine to the general population was as complex as the challenges of producing large quantities at a high rate.

Biden says his goal is to give the American population one million Covid-19 shots a day, to reach the 100 million mark in the first 100 days of his presidency.

When the death toll in the US has surpassed 500,000, Biden said he did not want to make a firm prediction of when the pandemic was contained.

"I believe we will get closer to normal by the end of this year. Hopefully this year's Christmas will be different from last year, but I can't promise that," Biden said.

Covid-19 broke out in December 2019, appeared in 219 countries and territories, with more than 111 million cases, nearly 2.5 million deaths, and more than 86 million people recovered globally.