SEATTLE — Concerns about the coronavirus intensified across the Pacific Northwest on Saturday, after a person from the Seattle area died and as two new cases emerged inside a nursing care facility in Kirkland, Washington, where dozens of other people were reported to be feeling sick.

Gov. Jay Inslee of Washington declared a state of emergency, and said officials were considering canceling sporting events, closing schools and taking any other steps needed to slow the spread of the virus. “If — and this is a big if — there is a social distancing strategy that becomes necessary, the emergency declaration would give us some legal authority,” he said.

At two schools that have had ties to cases, in Oregon and Washington, officials announced that they were shuttering buildings for several days, and ordering deep cleanings.

And in Kirkland, where a health care worker in her 40s at the Life Care Center, a long-term nursing facility, and a resident of the center, in her 70s, were reported Saturday to have tested positive for the virus, health officials expressed alarm at the possibility of more cases. Among 288 residents and workers at Life Care, more than 50 people — 25 health workers and 27 residents — have shown symptoms of respiratory illness or have been hospitalized for pneumonia, local health officials said.

“We are very concerned about an outbreak in a setting where there are many older people,” said Dr. Jeff Duchin, the health officer for Public Health Seattle & King County. A team of federal health workers was dispatched to Kirkland to assist local workers, and many more coronavirus tests were expected to be conducted in the coming days.

Older people are much more likely to face serious illness if infected with the coronavirus. They are also much more likely to die. An analysis of Chinese patients found that nearly 15% of infected people over age 80 died; of those in their 70s, 8% died.

Coronavirus vs. flu Definition: Both coronavirus and flu are categories. The coronavirus that originated in China, in late 2019 is a new strain of the virus – COVID-19. Coronavirus Q&A: Your questions answered Symptoms: Coronavirus and flu symptoms can be similar – a high temperature, cough, and then chest congestion. Prevention: Both the flu and coronavirus spread from person to person through droplets in the air from an infected person coughing, sneezing or talking. The common-sense steps to contain any virus, no matter the flu, coronavirus or a common cold, are washing hands frequently with soap, covering coughs and sneezes and disinfecting surfaces. The surgeon general does not recommend the use of masks for otherwise healthy people. Deaths: While COVID-19 is new and a growing worldwide threat, the flu annually sickens and kills vastly more people. About 17,000 people had died of COVID-19 through March 23, 2020. Compare that to 646,000 flu deaths worldwide this winter and 18,000 to 46,000 deaths in the U.S. per year. Got questions? North Carolina Poison Control has established a hotline, available 24/7 and staffed by nurses and pharmacists to answer questions about coronavirus, including symptoms, how to assess and reduce the risk of catching the virus and what to do if if coronavirus is suspected. Call 1-866-462-3821.

On Saturday afternoon, workers in plastic protective gear and masks could be seen rolling a patient, also in a mask, to an ambulance outside the center, a low-slung building on a side street tucked among small condo complexes and surrounded by pine trees. Officials said that testing for the virus was being done at a local hospital, and that the facility was not open for visits from patients’ family members or vendors as a precaution.

Nancy Butner, the northwest divisional vice president for Life Care Centers of America, said that many of the residents were showing only respiratory symptoms that were not necessarily tied to the coronavirus. In an interview, she said that residents were mostly staying in their rooms and that despite public health officials warnings of a possible “outbreak” at the facility, the mood inside was relaxed.

“We are encouraging people to remain in their rooms,” she said. “We have the equipment and supplies to take care of them, and people are doing what they need to do.”

Chad Bergevin, who lives across the street from the center, said he had learned of the situation in a text message from a neighbor. “It was like, ‘Wow, this is literally less than a football field away from my house,’ ” he said, adding that he was surprised to see people still seeming to come and go, near the center. “I’m sorry, if it were me, I’d have the place on lockdown,” he said.

The indications of possible spread, and the involvement of a nursing facility marked a new, urgent phase in the response to the virus in the United States, where 70 cases have been reported, and until Saturday, none had been fatal. Most of the cases could be explained by overseas travel or contact with someone who had been ill. This week, though, new cases, in California, Oregon and Washington, were the first in the U.S. in which the cause was mysterious and unknown — a sign, experts warned, that the virus, which has killed more than 2,800 people worldwide and sickened more than 86,000 others, might now be spreading in the U.S.

In the Northwest, especially, health officials were putting in place new precautions given the new cases. They were already discussing the possibility that they might recommend cancellations of public events. They began warning that life in the coming weeks may undergo dramatic change.

By Saturday, 10 people have been treated in Washington state, including the first case diagnosed in the U.S., a man in his 30s who had traveled in China and has since recovered; several patients were treated at a Spokane area hospital after returning from a cruise ship in Japan; and the first known coronavirus fatality in the U.S., a man in his 50s whose death was announced Saturday.

In announcing the death at a news conference, President Donald Trump said the victim was a “wonderful woman” in her 50s, but local officials later said the patient had been a man in his 50s. The Centers for Disease Control and Prevention later said that the patient was, in fact, a man, and that the agency had incorrectly described the patient as a woman.

Few details were known about the man who died, except that he had underlying health conditions and had been a patient at a hospital in Kirkland. He was not known to have traveled abroad, or to have had contact with anyone who had tested positive for the virus, adding to growing signs that the coronavirus may be spreading in the U.S. He also had no known connection to the nursing care facility, officials said. The new cases added to the fears of some residents. Noelle Salazar, an author in Bothell, Washington, was recovering from a surgery, and realized that she had been in the same hospital as the man who died.

“We weren’t in the same section, but it’s not comforting,” she said while recuperating at home. “I’m a little on edge right now for sure.”

Like many Americans, she has begun to take extra precautions in recent days: She wiped down her shopping cart at the grocery store for the first time, picked up extra vitamins and nonperishable food from the aisles and canceled a Pilates class to avoid getting too close to others.

Around the region, it was clear that residents were bracing. At a big-box store north of Seattle early Saturday, checkout lines were unusually long, snaking down aisles with carts loaded with all sorts of supplies.

In Oregon, a state that until Friday had not reported any cases of the coronavirus, officials say an employee of Forest Hills Elementary School in Lake Oswego, a suburb of Portland, appeared to have contracted the virus more than a week ago. The school would be closed for several days, and was being cleaned, but parents said they were uncertain and scared.

Gov. Kate Brown of Oregon said that she expected more cases, and that her state might take more aggressive action if the outbreak gets more severe. But, in the meantime, she said people did not need to take drastic action.

“I’m wanting to convey to Oregonians, and frankly folks on the entire West Coast: stay calm, continue on your daily lives and follow public health precautions,” Brown said. Dr. Dean Sidelinger, Oregon’s state health officer, said a broader closure of schools was an option the state could pursue at some point. “If we do notice spread in our community or multiple cases, that is certainly something we would consider on a case-by-case basis,” Sidelinger said.

Back at the school in Lake Oswego, parents were weighing how to go forward.

“I really don’t know how to process it at this point,” said Danielle Gaustad, a mother of three children, ages 3, 5 and 18. Her 5-year-old, who attends Forest Hills Elementary, had pneumonia several weeks ago, and her 3-year-old has severe asthma. “When people don’t understand an illness, and clearly no one understands coronavirus at this point, everybody gets scared,” Gaustad said.

Though the school has said it intends to reopen in a few days, Gaustad said she would not allow her children to go back to school this week. “I don’t know when I will, honestly,” she said. “It’s scary.”