The death toll at a New Hope nursing home that is being ravaged by the novel coronavirus has more than quadrupled in the past two weeks, claiming at least 55 residents.

St. Therese of New Hope, a senior care community with a 258-bed nursing home, disclosed the grim death count from COVID-19, the respiratory illness caused by the virus, in a notice sent to family members of residents. It said a total of 147 residents have tested positive for the virus, signaling that things still could get worse.

The facility is the site of the state's deadliest outbreak since the pandemic began. State health officials identified multiple lapses of infection-control standards at St. Therese during an onsite inspection last month, according to a Minnesota Department of Health report.

"We continue to fight this relentless virus in memory of our friends and neighbors lost," the facility said in its message to families.

The revelation of more deaths at St. Therese shows how rapidly the virus can spread in closed environments and comes as the state faces intensifying pressure to contain the spread of the virus in long-term care facilities. As of Friday, 434 of the 534 people who have died of COVID-19 in Minnesota lived in nursing homes or assisted-living facilities, state officials said.

Amid growing public concern, Health Commissioner Jan Malcolm unveiled a "battle plan" Thursday to address the rising COVID-19 death toll in long-term care facilities, including universal testing in facilities with outbreaks, the use of incentives, and even calling up the National Guard to replace caregivers who get sick. The agency has also shifted its priorities toward infection control during inspections and is conducting more visits of facilities with past performance problems, officials said.

The outbreak at St. Therese is considered among the most lethal in the nation, though official data are still not available nationally. There have been confirmed reports of COVID-19 outbreaks with 50 or more deaths at nursing homes in Massachusetts, New Jersey, New York and Texas. One home in New York had more than 70 deaths. On Friday, a new federal rule took effect requiring nursing homes to report deaths to the Centers for Disease Control and Prevention, as well as to residents and their families.

Like many of Minnesota's nursing homes hit by the virus, St. Therese has struggled to adhere to basic health and infection-control standards.

In an April 14 visit to the facility, state Department of Health inspectors found multiple lapses of infection-control procedures. The facility failed, for instance, to ensure that personal protection equipment (PPE) was worn and handled by staff "in a manner to reduce the risk of cross-contamination." Officials determined that the deficiency "had the potential to affect all residents, staff and visitors" at St. Therese, according to the report.

During the inspection, inspectors observed that a physical therapy assistant at St. Therese failed to discard a soiled gown before leaving a room with a COVID-19-infected patient, despite a sign ordering staff to discard gowns before leaving rooms. The therapy assistant also had no visible eye protection — a violation of the infection-control protocols during the pandemic, the report said.

The worker told state health inspectors that she "[hadn't] really had any" training on isolation precautions to be used when someone is suspected of being infected with COVID-19, the state report said. The employee also said she had been told to provide direct care to patients since the outbreak and that "numerous staff were out ill," according to the report.

State health inspectors observed a second case in which a nursing assistant failed to deposit a soiled gown properly before leaving a patient's room. The employee also walked to another patient's room 15 feet away before washing hands and arms, another violation of protocols, inspectors found.

In a statement, Barbara Rode, president and chief executive of St. Therese, said the infection-control deficiency was "relatively low-level" and has been addressed.

"That there was just one in a detailed inspection of a 258-bed skilled nursing home battling an invisible and sometimes fatal virus is a credit to our committed staff, which is working very hard under trying conditions to protect and care for our residents," Rode said.

St. Therese has a record of health and safety problems. In a 2018 inspection, the facility was cited 11 times for violations of minimum health and quality-of-life standards. These included failing to properly empty and remove urinary drainage bags, creating a foul odor in residents' rooms; failure to investigate bruising and alleviate pressure sores; and failure to provide basic grooming and routine dental care for residents, among other violations.

Many residents at St. Therese are doubled up in rooms separated by curtains, which some families believe may have contributed to the rapid spread of the virus through the facility. The facility has said it is working on a plan to have private rooms for its residents.

The facility's poor health and safety record fits a pattern among Minnesota nursing homes during the pandemic: Fully 75% of approximately 70 nursing homes in the state with at least one case of COVID-19 have been cited for not following infection-control rules over the last two inspection cycles starting in 2016, according to a recent Star Tribune analysis of federal health records.

In its message to families, St. Therese said the virus has been confined to its skilled nursing facility and has not spread to its senior apartments. Nearly 60 of its residents have recovered from the virus. "Our top priority is always to ensure everyone's safety, so we're taking additional measures above and beyond current guidelines," the facility said.