The number of new coronavirus cases in the US is at a six-month high, with 101,171 new infections confirmed as of Friday, according to the CDC, the highest rate since February, when vaccines still weren’t widely available to the population.

As the Delta variant continues to rage, particularly in states with low vaccination rates, the seven-day daily average of cases is also up to more than 72,000 cases, more than five times higher than just six weeks ago.

“If you look at the acceleration of the number of cases, the seven-day average has gone up substantially,” chief White House medical advisor Dr Anthony Fauci said last week.

“You know what we really need to do … we say it over and over again. and it’s the truth: We have 100 million people in this country who are eligible to be vaccinated who are not getting vaccinated.”

“We are seeing an outbreak of the unvaccinated,” he added.

A combination of the highly contagious nature of the Delta variant and lagging vaccination rates in certain states are driving the current surge, according to public health authorities.

Just seven states – Florida, Texas, Missouri, Arkansas, Louisiana, Alabama and Mississippi, all of which are among the states with the lowest numbers of vaccinations – are responsible for half of the country’s new cases and hospitalisations, the White House said on Thursday.

"We’re seeing terrifying #Covid19 trends in our hospitals," County Judge Lina Hidalgo, the top official of Harris County, the most populous county in Texas and home to the city of Houston, said on Twitter. "At this point if you’re unvaccinated by choice, you’re complicit in this crisis.”

Officials have warned that numbers could climb to as much as 200,000 new cases a day if America doesn’t rapidly expand the rate of people getting vaccinated.

Just over half of the US population is fully vaccinated, but the rate of new vaccinations had been slowing since the spring, and has only recently begun climbing back up.

Nearly 613,000 Americans have died of coronavirus so far, and the nature of the pandemic has changed over that time. The Delta variant, which spreads more quickly than the original strains of Covid that hit the US, now makes up more than 80 per cent of new infections in America.