Nearly 1 in 10 nursing homes in the United States has a publicly reported case of the novel coronavirus, a count that has soared in the past three days as several hard-hit states released the names of facilities after weeks of pressure from families, journalists and watchdog groups.

Through state reports and media accounts, The Washington Post has compiled a nationwide list of the more than 1,300 homes, with a death count that has spiraled into the thousands. The list is far from complete: More than half a dozen states with significant outbreaks have not released the names of facilities with cases of the virus, including Maryland and Virginia, where dozens of nursing home residents have died.

On Sunday, the Centers for Medicare and Medicaid Services (CMS) announced new reporting requirements, mandating that nursing homes inform residents, their families and the federal government about cases of covid-19, the disease the novel coronavirus causes. Under the new rules, the Centers for Disease Control and Prevention will collect the information.

CMS Administrator Seema Verma said Monday that the data, including deaths among residents and staff members, would be publicly released “in short order.”

For weeks, the reporting gaps have outraged families and patient advocates, who say transparency is a key tenant to public health.

“The failure to require early reporting in specific facilities was responsible for making the spread of the virus worse in nursing homes,” said Charlene Harrington, a sociology and nursing professor at the University of California at San Francisco who has studied nursing homes for more than 30 years.

States including Maryland, Virginia, Louisiana, Massachusetts, Michigan, Texas and Pennsylvania have not released the names of nursing homes, in some cases citing patient confidentiality. None of the states that have released the names of facilities have identified patients.

Though officials in New York reported that more than 300 nursing homes have positive cases, the state has released the names of 74 - those facilities with five or more deaths.

Even states that have publicly identified nursing homes have drawn criticism. Some have released facility names but no death counts. Others said they erroneously listed facilities without cases of the virus while leaving affected facilities off the list.

Officials in Ohio published a list Wednesday and took it down two days later, calling it inaccurate. Officials in California released a statewide list Friday, but only named facilities that reported cases within the prior 24 hours. The list did not include the Magnolia Rehabilitation & Nursing Center in Riverside, where dozens of patients were infected and the residents evacuated earlier this month after a majority of staff members did not show up for work.

“The tragic fact of the matter is that even these numbers represent only a fraction of the true toll the virus has taken in nursing homes across the state,” said Mike Dark, an attorney with the nonprofit California Advocates for Nursing Home Reform. “The figures are self-reported, and no state inspectors are on the ground in these nursing homes to check their accuracy.”

Without enough information, Harrington said, hospitals risk releasing fragile patients to nursing homes with outbreaks and families denied the chance to pull relatives from overwhelmed facilities.

“If they don’t know the virus is there, then they don’t even have that option to make that decision,” she said. “It’s just so grossly unfair.”

The federal government has not released a count of deaths in nursing homes, but state health departments and media reports have placed the number in the thousands. The counts have generally included all types of long-term care facilities, including assisted living facilities and group homes.

The Post looked at nursing homes that receive Medicare or Medicaid funding, finding more than 3,000 deaths and known coronavirus cases at about 1,350 facilities nationwide as of Monday morning. The Post’s analysis and list only includes nursing homes certified by the federal government, not other types of elder-care facilities such as assisted living centers or retirement homes.

The list of Medicare-certified nursing homes with cases of the virus more than doubled over the weekend as Florida, Illinois and California for the first time publicly released the names of facilities and other states expanded existing lists. New Jersey, second only to New York in the number of virus-related cases and deaths, released a list of more than 400 facilities Monday afternoon but some of those were not nursing homes.

Nearly 45% of nursing homes with known coronavirus cases nationwide were repeatedly cited in recent years for violating federal rules meant to protect residents from the spread of infections, The Post found. Experts say it’s difficult to know whether past infractions contributed to the spread of the virus, but infection control has become a top concern among public health officials.

In Oregon, state inspectors this month ordered immediate training in infection-control at a Portland nursing home with at least nine deaths. The facility did not screen staff members before they entered the building or ensure that caregivers washed their hands or wore personal protective equipment, inspectors found. In New Mexico, the state attorney general is investigating a nursing home with at least 13 deaths, saying managers did not require staffers to wear gloves or enforce social distancing.

As the crisis continues to mount, nursing home watchdog groups say they hope the new reporting requirements will add another level of accountability.

“Concerns about bad publicity must give way when lives are at stake,” Dark said.

Generally, state and federal regulations require nursing homes to report incidents that could impede the safety of residents. Inspection reports, including those triggered by complaints, are also required to be made public and are posted online.

The American Health Care Association and National Center for Assisted Living on Monday said providers are poised to share virus-related case information with the CDC.

“Knowledge is pivotal during a pandemic and our public health officials need to know where to send urgently needed resources,” Mark Parkinson, president of the group, said in a statement.

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The Washington Post’s Maria Sacchetti contributed to this report.