Top U.S. infectious disease expert Anthony Fauci said there was an "outbreak among the unvaccinated" and that the country was moving "in the wrong direction" in the fight against the Covid-19 pandemic.
"It's really an outbreak among the unvaccinated...which is the reason why we're out there practically pleading with unvaccinated people to go out and get vaccinated," Fauci said in an interview on CNN's State of the Union program Sunday.
"We're going in the wrong direction."
Fauci said many vulnerable people in the U.S. were still unvaccinated and they were the ones driving the rise in cases.
Vaccines are widely available in the U.S., and according to data from the Centers for Disease Control and Prevention, just under 60% of adults are fully vaccinated, with 68.8% having received at least one dose.
However, millions of individuals have not been vaccinated, and the Biden administration is urging Americans to get their shots - particularly in states where cases have increased in recent weeks.
Infection rates have risen in areas with lower vaccination rates. According to White House representative Jeffrey Zients, Florida, Texas and Missouri account for 40% of all new cases nationwide, with Florida accounting for one-fifth of all new cases.
Fauci added that compelling the vaccinated to wear masks was "under active consideration" by the government's top public health authorities, while booster doses may be recommended for persons who have been vaccinated but have impaired immune systems.
Jeff Duchin, the top public health official in Washington state's most populated county, also advised everyone to wear masks in indoor public spaces - even if they have been vaccinated - owing to the spread of the Delta variant.
According to the Centers for Disease Control and Prevention, 30 states have yet to fully vaccinate at least half of their residents. And, as of Friday, the daily average of persons receiving full vaccinations was the lowest since the end of January.