Open this photo in gallery The close quarters of the Grand Princess cruise ship – seen here off the coast of San Francisco on March 8, 2020 – has proven to be a fertile breeding ground for infection. JOSH EDELSON/AFP/Getty Images

The number of novel coronavirus cases in Canada has climbed to 69 as patients in Alberta doubled to four and B.C. officials declared an outbreak at a long-term care facility.

Several of Canada’s cases stem from a trip on the Grand Princess cruise ship to Mexico in mid-February. The close quarters of a cruise ship has proven to be a fertile breeding ground for infection.

Three of Alberta’s cases are tied to that trip, said Deena Hinshaw, Alberta’s Chief Medical Officer of Health. A man in his 40s from Edmonton, who has been infected, was not on the voyage. However, he travelled in the U.S. Midwest with a companion from British Columbia who was on the ship, Dr. Hinshaw told reporters on Sunday as she announced two new cases. The man’s companion is in B.C. and has the COVID-19 disease.

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Among Alberta’s newest patients are a man in his 60s from Edmonton who returned from the cruise on Feb. 21, and a woman in her 30s from Calgary. She had been in close contact with someone who had recently travelled in Ukraine, Turkey and the Netherlands. That person is also in Alberta and is being tested for the coronavirus.

“This marks four cases in four days. For many, this may be alarming. I want to underline that three of these four cases are linked to a single cruise ship,” she said.

Dr. Hinshaw said health officials are working to limit the spread after learning of the new cases, and the risk of infection remains low in Alberta.

All the patients are isolated at home and are expected to recover. She said Alberta can expect more cases in the coming weeks given the global contagion, but pointed out that of 299 tests done on Saturday, 297 were negative.

Besides Alberta’s four cases, Ontario has reported 34, B.C. 27 and Quebec four. In Toronto, the principal of Whitney Junior Public School forwarded a letter to parents on Sunday from the city’s medical officer of health warning of a possible exposure to the coronavirus. The letter stressed, however, that the risk to the school is low.

Ryan Bird, a Toronto District School Board spokesman, said on Sunday night that it was not a student or staff member who was exposed to the virus. He declined to identify the person who attended the school on March 4, citing privacy concerns, and said that Toronto Public Health would be responsible for sharing that type of information.

“The TDSB takes its lead from Toronto Public Health, which is not advising the school to take any additional precautions beyond those outlined in the letter,” he said.

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Around the world, there have been almost 108,000 reported coronavirus cases in more than 80 countries, with 3,662 deaths, most of them in China, where the outbreak began. More than 60,000 people are said to have recovered.

The epidemic has disrupted travel and numerous other industries, leading to massive sell-offs in financial markets, including in Canada. Last week, the Bank of Canada slashed its key interest rate by half a percentage point and signalled the potential for future cuts to deal with the “material negative shock” that COVID-19 poses to the economy.

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For most people, symptoms are mild, including a cough and fever. But the virus can severely impact the elderly and people with compromised immune systems. Dr. Hinshaw stressed, however, that even healthy, young people can get sick.

“For that reason, it is critical that all of us take seriously the recommendation to stay home if you have fever or cough," she said. “Unlike influenza, we do not have a vaccine or antiviral medication to prevent the COVID-19 illness. Also, unlike influenza, none of us have any previous immunity.”

In North Vancouver, two patients at a long-term care facility tested positive, prompting officials to declare an outbreak. The two cases are linked to B.C.’s first confirmed case of community transmission – a woman in her 50s with no recent travel history.

The woman is a health-care worker at the facility, and the new cases were discovered as part of an outbreak assessment, Provincial Health Officer Bonnie Henry said Saturday.

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“This is one of the scenarios that we have been, of course, most concerned about,” Dr. Henry said.

It is not yet known whether the health-care worker brought the virus into the facility or if residents were exposed to someone else, she said. Outbreak investigators will now look at the timing of symptoms and follow up with other contacts.

At the North Shore care facility, which has 139 government-subsidized beds and 65 private rooms and suites, residents are now monitored daily for respiratory illness, personal protective equipment is used for all interactions and communal gatherings have been halted. Meals are delivered to residents on trays in lieu of people dining together in a common area.

Christine Sorensen, president of the BC Nurses’ Union, said a shortage of nurses in the province means many are working at multiple sites, which could lead to exhaustion and further health risks.

“In this situation at Lynn Valley care home, those nurses will be working long hours," she said. "There has to be extra time allotted for hand washing and and caring for patients who will be in the facility and that additional time needs to be accounted for because it needs extra staffing.”

A B.C. woman who was on the Grand Princess cruise in February, and who had lingering cold symptoms, got word Sunday that she had tested negative. The woman went into isolation after undergoing testing. However, for 12 days before hearing about the cluster of cases, she interacted with family members and went to work, contact that she had worried may have placed others at risk. ​The Globe and Mail is keeping her name confidential because she is worried about the stigma of being connected to the virus.

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Amid reports about panic-buying at grocery stores for food and other staples, including toilet paper, Dr. Hinshaw said people should consider their neighbours who may be quarantined. “Rather than cleaning the stores out of toilet paper, probably what would be helpful is talking to neighbours, and family and friends about anyone in that community circle needing to stay home for two weeks, who could help support them by getting supplies,” she said.

With reports from Cherise Seucharan and Jill Mahoney

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