US health authorities have pleaded with Covid vaccine holdouts to roll up their sleeves and get their shots, as cases, hospitalisations and deaths surged.

“There is a clear message that is coming through: this is becoming a pandemic of the unvaccinated,” Centres for Disease Control and Prevention director Rochelle Walensky told reporters.

The agency reported more than 33,000 new cases on Thursday, bringing the seven-day average up to 26,306, a 70 per cent rise on the week before.

The seven-day average of hospital admissions is about 2,790 per day, an increase of 36pc. And after weeks of declines, the seven-day average of deaths was 211, an increase of 26pc, according to an AFP report.