A group of Senate Democrats is pressing the Biden administration for information about how health officials are prioritizing giving booster shots to nursing home residents and staff.

In a letter to Health and Human Services Secretary Xavier Becerra shared first with The Hill, the lawmakers, led by Sen. Bob Casey (D-Pa.), asked for "assurances that the Biden administration is doing everything in its power to provide nursing homes ready access to these safe and effective preventive measures."

Casey is chairman of the Special Committee on Aging. 

The letter was co-signed by Senate Finance Committee Chairman Ron Wyden (D-Ore.), as well as Sens. Mark Kelly (D-Ariz.) and Michael Bennet (D-Colo.).

Specifically, the Democrats said they want to know how the administration is ensuring booster and primary doses are delivered equitably, so that communities of color and other populations disproportionately affected by the pandemic will be able to access the vaccines.

"Research has shown that people of color are more likely to live in nursing homes with low vaccination rates, while Black and Hispanic people in the general population make up a disproportionately small share of booster dose recipients," they wrote. 

The omicron variant has brought new urgency to making sure residents and staff of nursing homes receive booster shots of COVID-19 vaccines. 

Infections among nursing home residents have been rising in recent weeks, averaging more than 4,000 new cases a week. According to experts and federal officials, many of these outbreaks are occurring in facilities that have yet to administer booster doses.

According to the Centers for Disease Control and Prevention, only about 57 percent of nursing home residents nationwide had received a booster as of Dec. 19. The rate for staff was much lower, at only 25 percent. 

CDC data shows fully vaccinated and boosted residents are 10 times less likely to contract COVID-19 than those who are unvaccinated, or even fully vaccinated but not boosted.