People inoculated against Covid-19 in high-risk parts of the United States should resume wearing masks indoors, the Centers for Disease Control, the country’s top government health body, announced on Wednesday.

This marks a change in masking guidelines in the United States. Earlier, fully vaccinated persons could gather indoors with other fully vaccinated people without wearing a mask or staying 6 feet apart.

The guidelines apply to parts of the US with at least 50 new cases per 1 lakh people in the last week. New case rates are particularly high in the South and Southwest, data from the CDC showed. In the states of Arkansas, Louisiana and Florida, every county has a high transmission rate.

On the other hand, parts of the Northeast where vaccination coverage is high are mostly experiencing moderate rates of community transmission.

The CDC also recommended indoor masks for all teachers, staff, students and visitors at schools nationwide, regardless of vaccination status.

Responding to the announcement, President Joe Biden said it showed that America needs to “do better” on vaccinations, AFP reported. He added that a mandate for the country’s more than two million federal workers was now “under consideration”.

“Today’s announcement makes clear that the most important protection we have against the Delta variant is the vaccine,” Biden tweeted. “Although most US adults are vaccinated, too many are not and that has to change.”

Biden also dismissed concerns that the new masking guidance could lead to confusion. He said Americans who remain unvaccinated are the ones who are “sowing enormous confusion”.

“The more we learn about this virus and the Delta variation, the more we have to be worried and concerned,” AP quoted the US president as saying. “And there’s only one thing we know for sure — if those other 100 million people got vaccinated, we’d be in a very different world.”

Covid-19 in the US

The latest seven-day average of daily cases in the US is more than 56,000, similar to levels last seen in April, AFP reported. Coronavirus cases have recently registered a rising trend as the Delta variant began to spread widely, especially in areas with lower vaccination rates.

Although 49% of the US population is fully vaccinated, inoculation rates in politically liberal states are higher than in conservative states.

In April, the CDC eased its guidelines on the wearing of masks outdoors, saying that fully vaccinated Americans no longer needed to cover their faces unless they were in a big crowd of strangers. In May, the authorities eased guidelines further, allowing fully vaccinated people to stop wearing masks outdoors in crowds and in most indoor settings.