A Crisis Standards of Care plan has been enacted at 10 hospital systems in Idaho, which is only done as a "last resort," Dave Jeppesen, director of the Idaho Department of Health and Welfare, said in a statement Tuesday.

The hospitals were chosen due to their "severe" shortages in beds and staffing as a result of a "massive increase" in COVID-19 hospitalizations, state officials said.

Crisis Standards of Care "means we have exhausted our resources to the point that our healthcare systems are unable to provide the treatment and care we expect," Jeppesen said. “This is a decision I was fervently hoping to avoid."

"When crisis standards of care are in effect, people who need medical care may experience care that is different from what they expect," state officials said. "For example, patients admitted to the hospital may find that hospital beds are not available or are in repurposed rooms (such as a conference room) or that needed equipment is not available."

Seventy-five percent of U.S. adults have now had at least one vaccine dose, Cyrus Shahpar, the White House's COVID-19 data director, tweeted Tuesday.

Sixty-four percent of U.S. adults are fully vaccinated, according to CDC data.

President Joe Biden on Thursday will deliver remarks on his plan to stop the spread of the delta variant and to boost vaccinations, the White House confirmed Tuesday.

Biden "will lay out a six pronged strategy … working across the public and private sectors," a White House official said.

On Friday, while addressing August's disappointing jobs report, Biden said, "there's no question the delta variant is why today’s jobs report isn’t stronger. … Next week, I’ll lay out the next steps that are going to -- we’re going to need to combat the delta variant, to address some of those fears and concerns."

Part of the strategy Biden referenced Friday is to ask states and local governments to consider using federal funding to extend unemployment benefits in hard-hit areas.

"I want to talk about how we’ll further protect our schools, our businesses, our economy, and our families from the threat of delta," Biden said Friday. "As we continue to fight the delta variant, the American Rescue Plan we passed continues to support families, businesses and communities. Even as some of the benefits that were provided are set to expire next week, states have the option to extend those benefits and the federal resources from the Rescue Plan to do so."

-ABC News' Sarah Kolinovsky

A third person has died in Japan after receiving a dose from one of three batches of Moderna's COVID-19 vaccine that have since been recalled due to contamination, according to the Japanese Ministry of Health, Labor and Welfare.

The 49-year-old man died on Aug. 12, one day after getting his second shot of the two-dose vaccine. His only known health issue was an allergy to buckwheat, the Japanese health ministry said in a statement Monday.

Two other men, aged 30 and 38, also died in August within days of getting their second Moderna shot. In all three cases, the men received doses from a batch manufactured in the same production line as another lot from which some unused vials were reported to contain foreign substances at multiple inoculation sites in Japan.

The deaths remain under investigation, and the Japanese health ministry said it has yet to establish any causal relationship with the vaccine.

The contaminated lot and two adjacent batches were suspended from use by the Japanese health ministry last month, pending an investigation. American drugmaker Moderna and its Japanese distribution partner Takeda Pharmaceutical Co. ultimately recalled the three lots, containing about 1.63 million doses, after an investigation confirmed the foreign matter to be high-grade stainless steel from manufacturing equipment.

The Japanese health ministry said that, based on the companies' analysis, it is unlikely the stainless steel contaminants pose any additional health risk.

Moderna and Takeda have yet to release statements on the third fatality, but the companies have previously said there is currently no evidence that the other two deaths were caused by the vaccine.

The Texas attorney general has filed lawsuits against six school districts that mandate masks, the office said Friday.

The lawsuits target the school districts of Richardson, Round Rock, Galveston, Elgin, Spring and Sherman for flouting Gov. Greg Abbott’s executive order prohibiting local entities from requiring masks -- what Texas Attorney General Ken Paxon referred to in a statement as "acts of political defiance."

In a statement to ABC News, Sylvia Wood, a spokesperson for Spring Independent School District, said the district had yet to be served and had no details about the lawsuit beyond a press release.

"Spring ISD will let the legal process unfold and allow the courts to decide the merits of the case," Wood said.

Elgin Independent School District Superintendent Jodi Duron also told ABC News the school district had not been served yet, and that schools in Travis County, part of Elgin ISD, are required to have students wear masks. "To the District’s knowledge, the Travis County Order has not been suspended," she said.

Round Rock Independent School District spokesperson Jenny LaCoste-Caputo told ABC News the school district is following Texas Education Agency guidance that allows for mask requirements "for adults or students for whom it is developmentally appropriate" and is working with local authorities "who advise us that masks remain an essential tool in stemming the spread of COVID-19 in our classrooms."

Sherman Independent School District told ABC News in a statement that it had not received any information on the lawsuit yet and for now "will continue to focus on promoting a safe and healthy learning environment for our students and staff."

ABC News has reached out to the other school districts for comment.

Nearly 90 school districts currently have mask mandates, according to a list compiled by Paxton's office. The attorney general anticipates more lawsuits if school districts "continue to defy state law," his office said in a statement.

Several school districts have sued the state to challenge the ban on mask mandates.

Last week, the Texas Education Agency said it is not enforcing the governor's executive order "as the result of ongoing litigation."