Thirteen patients at a Catholic-run nursing home in northeast Minneapolis have died from COVID-19, as the respiratory disease continues its deadly march through Minnesota’s senior care communities.

Catholic Eldercare reported the outbreak in a letter to family members and said it had begun to isolate residents infected with COVID-19 in a designated section of its 174-bed nursing home at 817 Main Street NE., which first reported cases of the virus among its residents and staff two weeks ago.

The deaths add to an already grim toll at long-term care facilities across the state, including a recent surge in large clusters of the virus. At least 32 residents died at St. Therese of New Hope, which includes a 258-bed nursing home with a troubled regulatory past. And 18 residents from North Ridge Health and Rehabilitation, also in New Hope, have died from the virus.

Deadly clusters of COVID-19 have shaken care centers, from Winona to Duluth, according to a review of death records by the Star Tribune.

For weeks, public health experts have warned that COVID-19 could spread rapidly in long-term care facilities, where people with chronic health problems and weak immune systems live in proximity and depend on the same staff for intimate daily needs, such as bathing and dressing.

In response, the facilities moved swiftly in March to impose unprecedented restrictions on visitors, train staff on infection-control procedures and stockpile emergency protective gear. State health officials also responded by sending in teams of infection-control specialists to facilities with COVID-19 outbreaks, while helping to coordinate the safe transfer of residents from overwhelmed facilities that could no longer care for them.

The goal was to prevent infections from spiraling out of control, and to prevent the sort of large-scale outbreaks that have devastated facilities in other states like New Jersey, infecting scores of people and killing dozens. “It is our goal to get in front of these facilities proactively,” said Michelle Larson, the Department of Health’s regulation division director, in a media call last week.

Yet the number and intensity of COVID-19 outbreaks in Minnesota’s care facilities have increased dramatically in the past few weeks, alarming public health experts and spurring calls for more aggressive action. All told, 78% of the 286 deaths from COVID-19 in Minnesota have been in long-term care facilities, including nursing homes and assisted-living facilities. The number of care facilities with at least one resident or staff member infected with the virus has more than tripled, to 111 centers statewide from 32, since the Department of Health began reporting the data April 4.

A number of elder advocacy groups are demanding universal testing for all residents and staff — even those showing no symptoms — to detect potential hot spots. So far, however, senior care facilities offered a patchwork of screening measures, such as daily temperature checks, that often fail to detect the virus.

Data from three recent studies in the United States show that as many as half of people with COVID-19 infections in care homes were asymptomatic, meaning they had no signs of the illness, when they were tested,

“Without universal testing, then how do these facilities know how bad the outbreak is?” asked Kristine Sundberg, executive director of Elder Voice Family Advocates, a volunteer group.

Gayle Kvenvold, president and chief executive of LeadingAge Minnesota, a long-term care industry group, said testing of asymptomatic staff would help address workforce shortages. She said her group knows of several facilities with staff who cannot provide care because they are stuck in quarantine and cannot access testing.

“Widespread testing is being recognized as the best way — along with proven infection-control measures, and other measures like visitor restrictions and screening — to protect our residents and staff, as well as track the path of the virus,” Kvenvold said.

Adding to the anxiety is the lack of clear and consistent standards for reporting deadly outbreaks.

Some facilities provide regular updates to families that include data on numbers of cases and deaths from COVID-19, and immediately notify residents and their relatives when someone tests positive. Others provide little or no information. For instance, many families with loved ones at St. Therese of New Hope said they were not told of the extent of the outbreak at the nursing home, or that residents were dying of the virus. As a result, these families argue, they were deprived of the opportunity to make informed judgments about their loved ones’ care.

Catholic Eldercare, by contrast, has begun providing weekly updates on COVID-19 at its facilities, which are sent via mail and posted on its website.

The letters reflect how quickly the virus can spread. As recently as April 9, the facility reported that it had no confirmed cases of COVID-19, though residents on three floors had developed respiratory symptoms. A week later, the facility said some residents and staff had been infected, and the facility was directing all residents to stay in their rooms. By last Tuesday, the facility had reported 12 deaths and eight other infected residents.

Laurie Benson learned a week ago that her 99-year-old mother, who lives at Catholic Eldercare’s nursing home, had tested positive for COVID-19. That afternoon, her mother was moved to a room on the third floor that she shares with another infected resident. Her mother suffers from dementia, and still does not understand that she has a potentially fatal disease, Benson said.

“My heart dropped when I heard the news,” she said. “My first thought was, `Are they going to treat my mom or just isolate her until she dies.’”

The Star Tribune has identified one additional fatality of a Catholic Eldercare resident through death records.

Catholic Eldercare said the current cases are confined to its nursing home, and do not include residents of its independent and assisted-living facilities.