The US could see 100,000 new coronavirus cases a day, top US infectious disease expert Anthony Fauci warned on Tuesday.

“We are now having 40-plus thousand new cases a day,” Fauci said in testimony to the Senate health and education committee.

“I would not be surprised if we go up to 100,000 a day if this does not turn around. And so I’m very concerned,” Fauci said.

The director of the National Institute for Allergy and Infectious Diseases declined to predict a figure for the expected number of deaths in the US from the pandemic but said it is going to be “disturbing”.

During his testimony, Centres for Disease Control and Prevention director Dr Robert Redfield said: “We all must take the personal responsibility to slow the transmission of Covid-19 and embrace the universal use of face coverings.

“Specifically, I’m addressing the younger members of our society, the millennials and Generation Zs.”

There have been at least 126,000 deaths from Covid-19 in the US so far. Four US states – Arizona, California, Florida and Texas – are accounting for about half of the new cases.