WASHINGTON (AP) — Responding to the ravages of COVID-19 in nursing homes, senior Democratic senators Tuesday introduced legislation to increase nurse staffing, improve infection control and bolster inspections.

The bill, from a group led by Sens. Ron Wyden of Oregon and Bob Casey of Pennsylvania, is part of a broader overhaul of long-term care just getting started. Separately, President Joe Biden is seeking $400 billion to expand home and community based care  as an alternative to nursing homes in the giant domestic agenda bill Democrats are pushing in Congress. His COVID relief law already provided a down payment.

Nursing homes and long-term care facilities house a tiny proportion of the U.S. population but they're estimated to account for about 3 in 10 deaths from COVID-19. Vaccines have finally brought relief, dramatically reducing cases and deaths, but concerns remain.

Some of the main provisions of the Senate bill would:

— Raise salaries and benefits for nursing home staff by giving states the option of an increase in federal Medicaid matching funds, available over six years. Low wages in the nursing home industry make for constant turnover, a critical problem even before the pandemic. The bill also starts a process for setting minimum staffing thresholds.

— Require nursing homes to have an infection prevention and control specialist.

— Require nursing homes to have a registered nurse available 24 hours a day, instead of the current eight hours.

— Bolster state inspections of nursing homes, and add more low-performing facilities to a "special focus" program that helps them improve quality.

— Forbid nursing homes from requiring residents and families to agree in advance to arbitration, thereby waiving their rights to go to court over disputes involving care.

The Congressional Budget Office has not put a price tag on the bill, but it could reach tens of billions of dollars.

"Families must have faith that loved ones receiving long-term care or care after a hospital stay will be safe and receive good-quality care," Wyden said in a statement. "The pandemic, myriad reports of abuse, and critical failures during natural disasters have shattered that foundation of trust and safety."

Nursing homes receive most of their financing through Medicaid and Medicare, and Wyden oversees both programs as chair of the Senate Finance Committee. Casey leads the Aging Committee. In the House, Ways and Means Chairman Richard Neal, D-Mass., and Energy and Commerce Chairman Frank Pallone, D-N.J., are also working on a nursing home overhaul. The four lawmakers wield clout, but prospects for the legislation are uncertain.

"These proposed measures would help improve staffing and increase accountability on the part of nursing homes," Harvard health policy professor David Grabowski said of the legislation. "Historically, we have often underfunded nursing homes but some facilities have also not spent public dollars on direct resident care as intended. Under this legislation, more funding will go to nursing homes for staffing, but more will be expected of them as well."

The bill would also launch an experiment to see if downsized nursing homes lead to better care and quality of life for residents. Those facilities would have between five and 14 residents, make private rooms available, feature accessible outdoors areas, and involve residents and families in decision-making.

The nursing home industry has been clamoring for more money from the government, and one of the leading trade groups, the American Health Care Association, welcomed the bill's promise of Medicaid funding for added nurses and infection prevention specialists.

But the group said it would strongly oppose restrictions on the use of arbitration agreements. And it raised concerns about the proposal to develop federal requirements for minimum staffing levels.

"There must be a comprehensive approach to staffing beyond just numbers," said Mark Parkinson, the group's president.