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A group of House Democrats is urging the Trump administration to track and publicly report coronavirus infections in nursing homes, as deaths from the virus are skyrocketing in long-term care facilities around the country.

The federal government does not keep a formal tally of coronavirus cases in nursing homes. An NBC News investigation this week found more than 5,600 deaths linked to long-term care facilities in 29 states, but limited testing and some states’ refusal to disclose data means that the national death toll is likely far higher.

The absence of comprehensive federal data risks endangering even more lives, Rep. Jan Schakowsky, D-Ill., wrote in a letter sent Wednesday to Health and Human Services Secretary Alex Azar and Seema Verma, administrator for the Centers for Medicare and Medicaid Services.

“[T]he Administration and the Congress lack essential information to adequately respond and protect older Americans and individuals with disabilities who rely on these facilities to survive and are particularly at risk for COVID-19,” Schakowsky wrote in the letter, which cited NBC News’ reporting on nursing home infections and deaths.

“We fear that there may be hundreds if not thousands more COVID-19 cases that have gone unreported,” Schakowsky said.

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The letter was signed by 77 other House Democrats, adding to the growing call from legislators, nursing home advocates and industry groups for the federal government to take more aggressive action to slow the deadly spread of the coronavirus by tracking infections in long-term care facilities.

Nearly 3,500 long-term care facilities across the United States have known coronavirus infections, according to health officials in 39 states. But not all states have released data on infections or deaths in these facilities, and some say they are not tracking them at all.

The last federal data was provided more than two weeks ago, showing infections in more than 400 nursing homes based on an informal survey of state health departments. The federal government has not provided any data on nursing home deaths.

Verma told reporters on Wednesday that the federal government would soon be doing more to track nursing home outbreaks, but she did not detail those plans.

The Centers for Medicare and Medicaid Services said in a statement that the agency "understands the need for better data from nursing homes during this unprecedented time and is working closely with our CDC colleagues on a process that we will be able to share more information about soon."

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Schakowsky said there is an urgent need for the Trump administration to act swiftly.

"If HHS fails to collect these data, we fear that the fatalities of congregate living facilities will linger in hindsight as a national and avoidable tragedy,” she said in the letter. "We must not leave any person behind."

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