Coronavirus has killed from coast to coast. It devastated a nursing home in Washington state and crept into the heartland. Across the United States, more than 100 people infected with the highly contagious new virus have now died – a toll that experts expect to rise quickly.

This country’s first fatal cases offer a preview of the challenges ahead, as Americans battle a disease that has killed thousands of people worldwide. The Washington Post has tracked every known U.S. death and has analyzed data provided by state and local health officials, families of the victims, and the Centers for Disease Control and Prevention.

Of the first 100 reported fatalities, many people appear to have had underlying health conditions, making it harder for their bodies to fight off covid-19, the disease caused by the novel coronavirus. Some had diabetes, kidney failure, hypertension or pulmonary ailments.

Nearly all – about 85% – were older than 60, and about 45% were older than 80. It’s unclear how some of them contracted the disease, but more than a third were living in residential care facilities when they became ill.

What is known about the scale of transmission and the high number of deaths among vulnerable populations – like at the Life Care Center of Kirkland in Washington state, where 27 of the facility’s 120 residents have died – has experts deeply concerned.

“I see that as the ‘canary in a coal mine’ situation,” said Fred Buckner, an attending physician at the University of Washington Medical Center. “I suspect it’s going to be taking off in other locations just like it is in the Seattle area. There’s no reason not to think that. Obviously, that means more deaths.”

In addition to the cluster of cases at Life Care Center, health authorities are monitoring cases at Lambeth House Retirement Community in New Orleans, a high-rise with about 250 residences and rooms. Of the four people who have died in New Orleans, two had been at Lambeth, where there are 12 additional cases, spokesman Greg Beuerman said.

Caitlin Rivers, an epidemiologist at Johns Hopkins University in Baltimore, said: “One particularly unsettling aspect of the outbreak [at Life Care Center] is the number of residents who have gotten sick and died in that facility. That’s a very high fraction.”

The early profiles of those who have fallen victim to covid-19 should be “a reminder that this virus can be very dangerous,” Rivers added. “It should serve as additional motivation to take every opportunity to reduce transmission.”

Darlene Kimball, 72, was one of those who died of covid-19 after a stay at Life Care Center.The avid gardener, animal lover and grandmother of five had been living with ovarian cancer for four years when she fell in mid-February and went to Life Care Center for rehabilitation, said her daughter, Tami Kahler.

Kimball at that point was lucid, talkative and mobile. She was in the process of finding a new oncologist.

But at Life Care Center, she developed a cough, becoming increasingly raspy and finding it difficult to breathe. While visiting Kimball – who was surrounded by her children, grandchildren and friends “24 hours a day,” Kahler said in an interview – family members noticed that many of the facility’s residents appeared to be sick. When Kimball began complaining of chest pains in late February, they urged a nurse to call the hospital.

It was only after the doctors and nurses had started wearing masks and gowns in Kimball’s presence; after her pneumonia was diagnosed and she was transferred to hospice care; and after the family pleaded for a coronavirus test that Kahler said her mother got one.

“They got the results back on Thursday,” March 5, Kahler said. “She died Friday.

Since the first U.S. death, on Feb. 26 in Washington state, a death has been reported somewhere in the United States nearly every day. At first, the numbers increased by two or three people, but by Friday, agencies were reporting more than half a dozen per day. Monday had the largest increase yet, when 24 deaths were reported in a single day.

People have died in 18 states.

U.S. testing continues to lag, obscuring the number of possible cases and fatalities, and almost all health departments have declined to release names of the victims, citing privacy laws.

The Centers for Disease Control and Prevention, in guidance issued to clinicians, has put the overall case fatality rate for patients with no underlying conditions at 0.9%. But the danger climbs with age and with chronic health conditions. For diabetics, the risk of death is 7%. For those with cardiovascular disease, it’s more than 10 percent, and for patients older than 80, the fatality rate is more than 14%.

The death rate is close to 50% for patients who develop the severe complications of respiratory failure, septic shock or multiple organ dysfunction. There is no treatment for covid-19 except supportive care.

The rising toll in the United States is following the pattern of deaths in the countries that have been hit the hardest.

In China, where the disease has killed more than 3,000, a study of early coronavirus cases in Wuhan province – where the first case was diagnosed – found that the odds of a patient dying rose with age and a host of underlying maladies, such as a lower level of organ function.

The study, published in the peer-reviewed medical journal the Lancet, found that preexisting health conditions were present in two-thirds of those who died, with hypertension and diabetes the most common afflictions.

A Kaiser Family Foundation report published last week hints at Americans’ vulnerabilities: Four in 10 adults are older than 60 or have serious underlying medical conditions. That means 105 million adults in the United States are at high risk of becoming severely ill if infected.

At Tulane Medical Center in New Orleans, John Dwyer, an infectious-disease specialist and an assistant professor of medicine, said this week that he was already seeing a disturbing harbinger of what is to come.

“We have several obese patients, which is one challenge I think we’re going to have nationwide in the United States because of the levels of obesity that we have,” said Dwyer, who on Monday said Tulane had “just received our sixth, seventh, eighth and ninth positive results about 10 minutes ago,” less than a week after running its first test.

“We have a lot of patients with diabetes and hypertension down here in Louisiana and those patients tend to do worse,” Dwyer said. “We also have a large amount of uninsured people who don’t always have access to care, and we have a lot of people who don’t have access to transportation.”

Of the nine people hospitalized at Tulane with the disease, four were in the intensive care unit, including a 27-year-old woman with multiple preexisting conditions, who had been mechanically intubated.

And none of those patients were known to have traveled to another country. Dwyer said he thinks cases in New Orleans have been spread locally, what scientists call community transmission.

At Life Care Center, family members and friends came and went until the facility imposed a strict isolation policy. Kahler said that as many as 30 people surrounded her mother during her final two weeks of illness, and that none have become sick.

But the daughter and son-in-law of Mary Whiteside, 90, another Life Care resident who also died, both contracted the disease, said Whiteside’s son James Whiteside . His sister spent days in intensive care and is now improving, he said.

The contagion that has shut down much of the nation has imposed the cruelest protocol on the sickest: Those who die are dying mostly alone.

Buckner, the doctor at the University of Washington Medical Center, saw his first coronavirus patient on March 4. The man, in his 80s, was a resident at the Ida Culver House Broadview senior home in Seattle, and was admitted to the emergency room with breathing trouble. The man was tested for coronavirus and his results came back the next day: positive.

Buckner and a colleague donned gowns, gloves and face masks to tell the man his diagnosis.

The man, speaking through his oxygen mask, was incredulous: “How the hell did I get that? How long does it take to get over this?”

Buckner delivered the answer gently.

The man’s other medical problems – kidney failure, high blood pressure and a history of lung disease – ruled out an experimental drug and a ventilator. He would remain in strict isolation, with no visitors allowed. His fate lay with the strength of his immune system.

Four days later, he died.

“That is a very painful, sad thing to see – someone in their last days having to go through it basically alone,” Buckner said. “They have the nurses and doctors, but they don’t have their family. That just adds to the tragedy of this.”

Mary Whiteside, too, spent her last four days alone, in a Seattle-area hospital, before her death. The great-grandmother and devoted University of Michigan sports fan had been recovering well from surgery at Life Care Center and was supposed to be discharged. Then the virus struck. Her relatives hope they will be able to hold a memorial service for her in the summer.

“I think the hardest thing for people losing family or friends to complications from this is that you can’t grieve properly because of what’s going on in our society,” said Matthew Gness, whose father, John Gness, 78, died in Florida from covid-19 on Saturday.

“You can’t really see your friends and family with all the social distancing and stuff, and there’s the preoccupation of having enough food and supplies, and just being distracted by all that kind of stuff,” said Gness, who works at a health-care laboratory and expects his professional life to soon be upended by the disease.

And now, “they are limiting everywhere – you can’t host a venue of 25 people or more,” he said. “So it interferes with even planning a funeral.”

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The Washington Post’s Julie Tate and Jennifer Jenkins contributed to this report.

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