More than 59,000 Americans are hospitalized with Covid-19, according to data from US Department of Health and Human Services. And overall, hospitalizations have been on the rise for more than three weeks.

The World Health Organization said the Delta variant has outcompeted other variants in most countries — making it the most common strain in much of the world.

“Even if the Omicron strain doesn’t turn out to be any worse, we are losing close to a thousand people every day from the Delta variant, and that in and of itself is a reason for people to get boosted,” Dr. Richard Besser, former acting director of the CDC, told CNN earlier this week.