Dr. Anthony Fauci in Washington DC on February 25, 2021.
  • Fauci said Sunday US Covid-19 cases were rising due to variants, increased travel, and restrictions easing.
  • New coronavirus infections hit 73,000 on March 27, up from fewer than 50,000 on 11 March.
  • "You're really in danger of a surge coming up," Fauci told Face the Nation.
  • For more stories visit Business Insider.

Dr. Anthony Fauci, the top US infectious diseases expert, warned Sunday that US Covid-19 cases were rising again because of infectious coronavirus variants, people traveling more, and states easing restrictions too soon.

The number of new coronavirus infections in the US was more than 73,000 on March 27, according to the Johns Hopkins University,up from less than 50,000 March 11. At its January peak, the number of new cases in the US was more than 250,000.

"Variants we take seriously and are concerned, but it is not only the variants that are doing that," Fauci, President Joe Biden's chief medical advisor, told Face the Nation.

Fauci said that travel around spring break and states prematurely "pulling back" on Covid-19 restrictions were likely causes too. More than 11 states have eased restrictions, despite the Centers for Disease Control and Prevention (CDC) warning that "now is not the time".

On March 12, the US saw more than 1.3 million travelers go through its airports - the most of any other day in the past year.

"When you're coming down from a big peak and you reach a point and start to plateau, once you stay at that plateau, you're really in danger of a surge coming up," Fauci said. "That's what we're starting to see."

Meanwhile, highly contagious coronavirus variants are spreading throughout the US, including the variant first found in the UK, B.1.1.7; the variant first found in South Africa, B.1.351; and the variant first detected in Brazil, P1.

Oklahoma is the only US state that hasn't detected B.1.1.7, which is between 30% and 50% more infectious, according to the CDC.

Dr. Rochelle Walensky, CDC director, said Friday that she was "deeply concerned about this trajectory" and advised against travel.

Fauci explained Sunday that the problem with travel was the congregation of people.

Fauci remained optimistic, however, saying it was "conceivable" that there would be a "good degree of flexibility during the summer," including things like kids summer camps, if a "considerable percentage" of the population were vaccinated and the community rate of infection fell.

Fauci said that the US was giving out 3.5 million vaccinations a day. So far, 36.2% of adult Americans are fully immunized, and more than 93 million have had a single dose of a Covid-19 vaccine, according to the CDC.

Biden surpassed his goal of giving 100 million vaccine doses to Americans in his first 100 days in office on March 19, but increased his target six days later, aiming to reach 200 million doses before his 100th day in office, which is April 30.

"If we keep up at that pace, invariably that's going to drive the rate and the level of infections per day to a much, much lower level," Fauci said.

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