Fewer than half of all nursing home residents in the United States have received the latest coronavirus vaccine booster shot – and rates among nursing home staff are even worse – raising concerns that vulnerable elderly people face a spike in preventable COVID-19 deaths this winter.

The Food and Drug Administration authorized the mRNA bivalent boosters produced by Pfizer-BioNTech and Moderna, which were designed to work against two omicron mutations and the original coronavirus, on Aug. 31. More than three months later, nursing homes around the country have been slow to get their residents and staff vaccinated, according to data gathered by the Centers for Disease Control and Prevention.

As of Dec. 4, only 47 percent of residents in nursing homes have received the latest booster; the rate for nursing home staff was 22 percent.

“We’re certainly expecting to see an increase in deaths in nursing home residents in the coming months because that is what we have historically seen, especially given how low the rate of the latest booster take up is,” said Priya Chidambaram, senior policy analyst at the Kaiser Family Foundation, which published a report on the booster shortfalls this month.

Gov. Ned Lamont, left, talks with Jeanne Peters, 95, during a visit to The Reservoir nursing home, after she was given the first COVID-19 vaccination in 2020, in West Hartford, Conn. Stephen Dunn, Pool/Associated Press, file

Among states, according to the Kaiser Family Foundation analysis, Arizona was at the bottom with 24 percent of nursing home residents fully boosted as of Nov. 20; South Dakota had the highest rate at 73 percent.

Nursing home deaths attributed to COVID have reached 161,000, nearly 15 percent of total fatal cases in the United States. Most of those people died in the initial year of the pandemic, with a staggering spike in deaths the first winter.

The current rate of deaths doesn’t come close to what it was in 2020, before the vaccines, or even when the omicron variant took over last winter. But more than 300 residents a week have been dying recently in nursing homes and that number is likely to rise as holiday gatherings and cold weather fuel an uptick in infections.

In the total U.S. population, elderly people have been hit hardest this season, with people 75 and over making up 71 percent of all COVID fatalities in November, according to the CDC.

Industry representatives said they are facing head winds in the latest booster push.

LeadingAge, the industry group representing nonprofit nursing homes in the United States, said its member nursing homes have encountered “vaccine fatigue” among residents and staff.

Most nursing homes do not have on-site pharmacies. So they must bring in outside companies with pharmacists who are registered with state and federal authorities to administer vaccines to their residents. But appointments to administer vaccines are hard to schedule if only a few residents want the boosters, said Katie Smith Sloan, president and CEO of LeadingAge.

“Nursing homes can’t force anybody to get the vaccine boosters, but they certainly can encourage people,” she said.

LeadingAge and the other major industry group, the American Health Care Association/National Center for Assisted Living, said recently that many residents believe the latest strains of the coronavirus are not as serious as earlier mutations. The patients also think they are immune already if they have received shots earlier in the pandemic or been infected previously.

“COVID fatigue is enormous,” industry associations told the Biden administration in a public set of recommendations.

But some facilities have achieved a high rate of administering the new boosters, showing that a concerted effort can yield results. In Tacoma, Wash., the nursing home at the eliseo retirement community has given bivalent boosters to about 70 percent of its residents and 50 percent of staff, said Kevin McFeely, the facility’s president and chief executive. Washington state health authorities have been aggressive about pushing shots and educating people about their benefits, he said. On-site vaccinations, he added, have been conducted by a long-term-care pharmacy contractor and coordinated by the facility’s infection prevention nurse.

In response to industry suggestions, the White House announced last week it was adding nursing home staff to the pool of eligible people who can give the injections. It also is urging governors in states with low rates to push their local nursing homes to do more. Additionally, it is asking hospitals to make sure that elderly patients being sent to nursing homes are given booster shots before being discharged.

“There are still too many older Americans who have not gotten their immunity updated, who have not gotten themselves protected,” White House COVID response coordinator Ashish Jha told reporters at the White House last week.

Regarding staff vaccinations, a federal requirement imposed in November 2021 that staff members get the initial doses drove a high compliance rate: 91 percent, according to a survey this year by the Health and Human Services Office of Inspector General. But boosters have remained voluntary for staff, and the numbers tell the story. A little over half of staff nationwide got the first booster shot, the inspector general found.

Reasons for low uptake among staff have included worry about safety, union opposition to mandates and workers’ concern about missing work because of side effects.

More recently, some advocates have questioned what they see as mixed messages coming from the administration. The Centers for Medicare and Medicaid Services, the agency that regulates nursing homes, in October relaxed penalties for failing to meet vaccine mandates. It cited the success of earlier vaccination efforts as the reason for the softer approach.

“They got people vaccinated and it made a big difference. But to say that it was successful and therefore we’re going to let up on enforcement, to me just didn’t make sense,” said Toby Edelman, senior policy attorney with the nonprofit Center for Medicare Advocacy. The administration did not respond to a request for comment.

A focused effort by the federal government in 2021, which worked with Walgreens and CVS to dispatch vaccination teams directly into nursing homes as soon as the first doses became available, dramatically reduced the amount of deaths and serious illness.

But immunity from the original round of shots waned over time. The new boosters do not prevent all infections, but they are effective at preventing serious illness, hospitalizations and deaths, according to the CDC. The agency said the bivalent boosters cut the risk of COVID hospitalization by at least half.

Yet the concerted effort to bring vaccine clinics into the facilities that was so successful in 2021 is absent this year.

“It doesn’t seem to be as accessible as it might have been before,” said Lori Smetanka, executive director of the National Consumer Voice for Quality Long-Term Care, a nonprofit advocacy group. “There’s real inconsistency. Some have been offered the vaccine and some haven’t.”