Jesse Jackson, wife hospitalized with COVID-19

Children's of Mississippi, the state's only pediatric hospital, reported a record number of patients Thursday.

There are 28 children, all unvaccinated, with confirmed or suspected cases of COVID-19, the highest since the start of the pandemic, the hospital said on Facebook. Among those, eight children are in the intensive care unit, including five not yet old enough to receive the vaccine, the hospital said.

"The best way to protect ALL of Mississippi's kids from COVID-19 is for everyone age 12 and up to get vaccinated," said the hospital, which is part of the University of Mississippi Medical Center in Jackson.

Nearly 43% of Mississippi residents ages 12 and up are fully vaccinated, according to CDC data, one of the lowest rates in the country.

Connecticut Gov. Ned Lamont announced new COVID-19 vaccine requirements for state employees Thursday.

State employees in hospital facilities will be required to get vaccinated, while all other state employees, K-12 teachers and staff and early childhood staff will need to get tested weekly if they are not vaccinated, he said. 

The requirements go into effect Sept. 27 and are on top of a previously announced vaccine mandate for long-term care employees.

"We've done very well, thank you Connecticut, in terms of people getting vaccinated," Lamont said at a press briefing. "We've got to do better."

More than 74% of Connecticut residents ages 12 and up are fully vaccinated, according to Centers for Disease Control and Prevention data.

Five states have fewer than 10% of their intensive care unit beds available, according to federal data.

Alabama has reached 100% ICU capacity, while Georgia is at 94% capacity, Florida at 93.18%, Mississippi at 93.01% and Texas at 92.72%, according to the latest data from the U.S. Department of Health and Human Services.

Nationwide, nearly 78% of staffed adult ICU beds are occupied, according to HHS, as the U.S. continues to experience its steepest increase in COVID-19-related hospitalizations since the winter of 2020. There are nearly 93,000 patients now hospitalized across the country with COVID-19, according to federal data.

Overnight, the U.S. recorded its fourth day with more than 140,000 new COVID-19 cases in the last seven days. The country's new case average has now surged to 130,000, up 13.2% in the last week, an ABC News analysis found.

-ABC News' Arielle Mitropoulos

More than 1 million COVID-19 vaccine doses were administered in the past 24 hours, including 562,000 first doses, a White House official confirmed to ABC News Thursday.

It's the first time 1 million doses in a single day have been logged in close to seven weeks, the official added, "a 31% week-over-week increase in the daily average of people completing their vaccine series."

-ABC News' Justin Gomez