US authorizes COVID-19 booster jabs

The United States on Thursday authorized an extra COVID-19 vaccine dose for people with weakened immune systems, as the country struggles to impede the rapid spread of the Delta variant.

Emergency use authorization for a third injection of Pfizer-BioNTech and Moderna vaccines was granted by regulator US Food and Drug Administration.

"The country has entered yet another wave of the COVID-19 pandemic, and the FDA is especially cognizant that immunocom-promised people are particularly at risk for severe disease," said acting FDA Commissioner Janet Woodcock in a statement.

US health authorities had been debating whether a third dose may be required, following a similar move by Israel.

Some media reports suggest that 1 million people in the US may have had unauthorized third doses in an attempt to increase protection.

Earlier this month, the US rejected an appeal from the World Health Organization for a moratorium on booster shots to help ease the drastic inequity in dose distribution between rich and poor nations.

More than 619,000 people have died in the country from COVID-19, with case numbers increasing sharply in recent months due to the spread of the Delta variant.

The variant has pushed up US infections to averages of about 100,000 a day, federal data show, levels last breached before vaccines were available in the country. It accounts for about 93 percent of the nation's cases.

The country's rapid vaccination program has slowed particularly in politically conservative regions in the South and Midwest, and among younger people, those with lower income and racial minorities.

"Right now at this moment, other than the immune compromised, we're not going to be giving boosters to people," said Anthony Fauci, top US COVID-19 adviser, to NBC on Thursday.

"But we will be following them very carefully, and if they do need it, we'll be ready to give it to them ... inevitably there will be a time when we will have to give boosts."

So far, only half the US population is fully vaccinated.

Florida has had more cases than all 30 states with the lowest case rates combined, said the White House pandemic response team on Thursday. Florida and Texas alone have accounted for nearly 40 percent of new hospitalizations across the country. The two states also have far more children under the age of 18 hospitalized with COVID-19 in the last week than any other state, according to the Centers for Disease Control and Prevention.

ICU beds full

On Thursday, Mississippi reported more than 4,400 cases and 20 deaths. More than 1,500 people in the state are hospitalized, and nearly 400 ICU beds are filled with infected patients. Mississippi is averaging nearly 2,700 new infections a day in the past week－a 54 percent spike in the past seven days, The Washington Post said.

The surge in coronavirus patients and a shortage of healthcare workers and intensive care unit beds have pushed Mississippi's hospital system to the brink of "failure", warned state health officials, saying drastic federal intervention was needed to help the state grapple with the thousands of new daily infections that have overwhelmed doctors and nurses.

Dr Alan Jones, associate vice-chancellor for clinical affairs at the University of Mississippi Medical Center, said there are few intensive care unit beds available in the state.

"If we continue that trajectory, within the next five to seven to 10 days, I think we're going to see failure of the hospital system in Mississippi," said Jones during a news conference on Wednesday. "Hospitals are full from Memphis to Gulf-port, Natchez to Meridian."

More than 25,000 employees of the US Health and Services Department who work directly with patients will be required to be vaccinated, said the agency on Thursday.

The nation's largest teachers' union on Thursday said it supported requiring all teachers to get vaccinated against COVID-19 or submit to regular testing.

Ai Heping in New York and agencies contributed to this story.