If you are not vaccinated against Covid-19, you shouldn't go into a bar or restaurant, expert says - CNN

In 34 of those states, the rate of new cases increased by more than 50%.

And hospitals are filling up with Covid-19 patients again, except now, patients are younger than before, said doctors in Alabama, Mississippi, Florida and Missouri.

Despite many officials' encouragement and experts warning that the best protection from the virus comes from vaccinations, only 49.1% of the US population is vaccinated, according to data from the US Centers for Disease Control and Prevention.

If a large swath of people remains resistant to vaccination, Reiner said, the US is left with two options to control the spread: shut down businesses -- which few people want to do -- or return to masks.

"The only way to get the unvaccinated to mask up is to mask everyone up," Reiner said.

"The equivalent of that with the Delta variant is not 15 minutes, it's one second."

That means people might need to do more than one thing to protect themselves from the more transmissible variant, said Gounder, an infectious diseases specialist at NYU's Grossman School of Medicine.

In addition to vaccination, "Some of the other layers that we should consider would be masking indoors when you're outside of your household bubble, optimizing ventilation in the home -- just opening your window works really well," she said.

People should think in terms of how much virus there is in the air, plus how long they might be in contact with that virus-laden air.

On Sunday, Los Angeles County officials said hospitalizations surpassed 700 for the first time since March.

In Florida, state health data shows new case positivity nearly doubled in two weeks, from 7.8% the week of July 2 to 15.1%.

A total of 870 hospitalized patients were reported Sunday in Alabama, according to the state's public health Covid-19 dashboard.

Hospitalizations there have been steadily rising since early July: On July 4 there were just 213 hospitalized patients reported.

And Louisiana now has the highest increase in cases per capita in the US, state officials said Friday.

"We know that more than 80% of these are the Delta variant -- that is what's causing this surge," Gov.