Nearly 600 patients wait for hospital beds in Houston as city sees surge in COVID cases

The National Education Association, the largest teacher's union in the U.S., has announced support for COVID-19 vaccine requirements or regular testing for teachers. 

NEA President Becky Pringle said in a statement, "As we enter a new school year amidst a rapidly spreading Delta variant and lagging public vaccination rates, it is clear that the vaccination of those eligible is one of the most effective ways to keep schools safe, and they must be coupled with other proven mitigation strategies."

Nearly 90% of NEA members say they're fully vaccinated, the union said.

-ABC News' Whitney Lloyd

In hard-hit Louisiana, Louisiana State University will mandate the COVID-19 vaccine once the FDA grants full approval, LSU President William F. Tate IV said in a statement.

"We expect the FDA to fully authorize one or more of the COVID vaccines in the next few weeks," Tate said. "In the meantime, I strongly encourage you to go ahead and get vaccinated now."

LSU's live mascot, a tiger, has already been vaccinated.

Going a step beyond the general guidelines for the federal workforce -- which is to get vaccinated or be subject to masking/testing -- the Department of Health and Human Services is offering only one option for its patient-facing employees: get vaccinated.

The 25,000 HHS employees who will be required to get vaccinated are concentrated within the Indian Health Service and National Institute of Health, as well as the U.S. Public Health Service Commissioned Corps.

The deadline to get vaccinated is the end of September, according to an HHS official familiar with the plan. There will be exemptions for religious or medical reasons.

-ABC News' Sarah Kolinovsky

The Food and Drug Administration is poised to authorize a third COVID shot for the immunocompromised on Thursday, sources told ABC News.

About 3% of the population would qualify, Dr. Anthony Fauci told ABC News' "Good Morning America."

He said the boosters would be "for example, people who have transplantation and are on immunosuppressive drugs for that; people on therapy for cancer -- cancer chemotherapy; people with advanced HIV disease; and people who are receiving immune suppressive therapy for a variety of diseases."

When asked if the boosters would be available to everyone, Fauci said, "You have to follow people, which we're doing in real-time, mainly a non-immune compromised, either an elderly person or a younger person … to determine if their level of protection goes below a critical level."

He added, "If and when it does, and it's likely that it will because no vaccine is gonna last forever, we're gonna be ready and have a plan to give those individuals the additional dose they might need."